WO2013012271A2 - Method for preparing light absorption layer for solar cell, solar cell including light absorption layer, and manufacturing method thereof - Google Patents

Method for preparing light absorption layer for solar cell, solar cell including light absorption layer, and manufacturing method thereof Download PDF

Info

Publication number
WO2013012271A2
WO2013012271A2 PCT/KR2012/005783 KR2012005783W WO2013012271A2 WO 2013012271 A2 WO2013012271 A2 WO 2013012271A2 KR 2012005783 W KR2012005783 W KR 2012005783W WO 2013012271 A2 WO2013012271 A2 WO 2013012271A2
Authority
WO
WIPO (PCT)
Prior art keywords
electrode
layer
solar cell
light absorbing
light absorption
Prior art date
Application number
PCT/KR2012/005783
Other languages
French (fr)
Korean (ko)
Other versions
WO2013012271A3 (en
Inventor
김태환
추동철
김대훈
Original Assignee
한양대학교 산학협력단
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 한양대학교 산학협력단 filed Critical 한양대학교 산학협력단
Publication of WO2013012271A2 publication Critical patent/WO2013012271A2/en
Publication of WO2013012271A3 publication Critical patent/WO2013012271A3/en

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
    • H01L31/042—PV modules or arrays of single PV cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02—Details
    • H01L31/0236—Special surface textures
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K71/00—Manufacture or treatment specially adapted for the organic devices covered by this subclass
    • H10K71/10—Deposition of organic active material
    • H10K71/12—Deposition of organic active material using liquid deposition, e.g. spin coating
    • H10K71/15—Deposition of organic active material using liquid deposition, e.g. spin coating characterised by the solvent used
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K2102/00—Constructional details relating to the organic devices covered by this subclass
    • H10K2102/10—Transparent electrodes, e.g. using graphene
    • H10K2102/101—Transparent electrodes, e.g. using graphene comprising transparent conductive oxides [TCO]
    • H10K2102/103—Transparent electrodes, e.g. using graphene comprising transparent conductive oxides [TCO] comprising indium oxides, e.g. ITO
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
    • H10K30/30—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation comprising bulk heterojunctions, e.g. interpenetrating networks of donor and acceptor material domains
    • H10K30/35—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation comprising bulk heterojunctions, e.g. interpenetrating networks of donor and acceptor material domains comprising inorganic nanostructures, e.g. CdSe nanoparticles
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
    • H10K30/50—Photovoltaic [PV] devices
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H10K85/10—Organic polymers or oligomers
    • H10K85/111—Organic polymers or oligomers comprising aromatic, heteroaromatic, or aryl chains, e.g. polyaniline, polyphenylene or polyphenylene vinylene
    • H10K85/113—Heteroaromatic compounds comprising sulfur or selene, e.g. polythiophene
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H10K85/10—Organic polymers or oligomers
    • H10K85/111—Organic polymers or oligomers comprising aromatic, heteroaromatic, or aryl chains, e.g. polyaniline, polyphenylene or polyphenylene vinylene
    • H10K85/113—Heteroaromatic compounds comprising sulfur or selene, e.g. polythiophene
    • H10K85/1135—Polyethylene dioxythiophene [PEDOT]; Derivatives thereof
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H10K85/20—Carbon compounds, e.g. carbon nanotubes or fullerenes
    • H10K85/211—Fullerenes, e.g. C60
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H10K85/30—Coordination compounds
    • H10K85/341—Transition metal complexes, e.g. Ru(II)polypyridine complexes
    • H10K85/342—Transition metal complexes, e.g. Ru(II)polypyridine complexes comprising iridium
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/549—Organic PV cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present invention relates to a method for manufacturing a light absorbing layer for a solar cell, a solar cell including the light absorbing layer, and a method for manufacturing the same, and more particularly, using a good solvent and a poor solvent on a surface voluntarily.
  • the present invention relates to a method for manufacturing a light absorbing layer for solar cells that forms irregularities, a solar cell including the light absorbing layer, and a method for manufacturing the same.
  • next-generation energy sources that can solve energy problems because they have less pollution, infinite resources, and can be used semi-permanently.
  • Solar cells are semiconductor devices that convert light energy directly into electrical energy using the photovoltaic effect.
  • the solar cell may be broadly classified into an inorganic solar cell, an dye-sensitized solar cell, and an organic solar cell according to the material of the photoactive layer.
  • silicon-based solar cells which are a kind of inorganic solar cells, face various problems such as photoelectric conversion efficiency reaching a limit and supply of silicon raw materials becomes difficult due to sudden increase in demand. Therefore, active researches on organic solar cells have been conducted as an alternative.
  • the organic solar cell is manufactured by stacking an organic thin film, a flexible substrate can be used, and the organic solar cell can be manufactured in various structures compared to the inorganic solar cell.
  • the absorption coefficient of the organic molecules used as the light absorption layer is high, and even a fine thin film of about 100 nm can sufficiently absorb sunlight. Therefore, the organic solar cell can be easily manufactured as a micro device at low cost, and has excellent advantages in bending property and workability due to the characteristics of the organic material, and can be applied to various fields.
  • the organic solar cell has a junction structure of an electron donor (D) and an electron acceptor (A).
  • D electron donor
  • A electron acceptor
  • the organic solar cell When the organic solar cell is irradiated with light, the light is absorbed to form an electron-hole pair, that is, an exciton, in an excited state.
  • the excitons diffuse in an arbitrary direction and are separated into electrons and holes when they meet the D-A interface.
  • the time taken for the exciton to recombine and disappear is very short, 100 ps (picoseconds)
  • the distance that the exciton can diffuse without recombination is known to be about 10 nm. Therefore, in order for the excitons to be separated without recombination to generate electrons and holes, the excitons must be formed within 10 nm at the D-A junction interface.
  • the thickness of the photoactive layer can be made thin to reduce the exciton travel distance. However, in this case, the amount of light absorption decreases and thus the photoelectric conversion efficiency is lowered.
  • Korean Patent No. 10-0959760 discloses a technique of forming a nano bar using aluminum anodized oxide (AAO) as a nanoporous template.
  • Korean Patent Publication No. 10-2011-0068216 discloses a photoactive layer through chemical vapor deposition (CVD) and chemical dry etching such as LPCVD, PECVD, and hot chemical vapor deposition.
  • CVD chemical vapor deposition
  • PECVD PECVD
  • hot chemical vapor deposition A technique for forming a photoelectric conversion layer pattern composed of a plurality of nanorods is disclosed.
  • the above methods mainly grow the nanorods using chemical methods, many of the structural impurities may be included.
  • the impurities hinder the diffusion of excitons or induce recombination, thereby degrading photoelectric conversion efficiency.
  • the above methods have a problem in that the cost of performing equipment is high, and high vacuum is required, resulting in high manufacturing costs.
  • An object of the present invention is to provide a method for manufacturing a light absorption layer of a solar cell to reduce the recombination of excitons to increase the transport efficiency of the charge to move to the anode and cathode.
  • An object of the present invention is to provide a solar cell having improved photoelectric conversion efficiency by providing irregularities in the surface of the light absorption layer.
  • the problem to be solved by the present invention is to provide a method for manufacturing a solar cell is easy to control the process conditions using a solution process, and low manufacturing cost.
  • One aspect of the present invention to achieve the above object is to prepare a mixed solution containing a good solvent, poor solvent and light absorbing material, agitating the mixed solution to obtain a spontaneously formed nano-aggregate, the nano-aggregate It comprises the step of applying a composition containing a solar cell electrode or an organic thin film layer and the heat treatment of the applied composition to form a light absorption layer having a concave-convex structure.
  • the light absorbing material may be at least one selected from a light absorbing organic material and a light absorbing inorganic material.
  • the light absorbing organic material may be at least one selected from organic semiconductor materials and phosphorescent materials.
  • the light absorbing inorganic material may be an inorganic semiconductor material.
  • One of the good solvent and the poor solvent is selected from the group consisting of chlorobenzene, dichlorobenzene, chloroform, toluene and hexane, and the other is PGMEA, ethylene glycol, tetraethoxysilane, dibutyl ether, dimethylformamide , Xylene, water, methanol, ethanol and propanol.
  • the nano-aggregate may be at least one selected from an inorganic semiconductor material, a combination of an organic semiconductor material and a phosphor, and a combination of an organic semiconductor material and an inorganic semiconductor material.
  • Applying the composition containing the nano-aggregate on the solar cell electrode or the organic thin film layer may be carried out by any one of spin coating, spray coating, dip coating, screen printing, inkjet printing, gravure printing and offset printing.
  • One aspect of the present invention for achieving the above object is a first electrode, a light absorption layer formed on the first electrode, including a light absorbing material, an electron transport layer formed on the light absorbing layer and the second formed on the electron transport layer And an electrode, wherein the light absorbing layer is formed with nanoaggregates protruding in a vertical direction on top of the lower thin film layer to form irregularities, and the electron transport layer fills the space between the nanoaggregates and covers the nanoaggregates.
  • the display device may further include a hole transport layer interposed between the first electrode and the light absorption layer, and further include a charge injection layer interposed between the electron transport layer and the second electrode.
  • the light absorbing material may be at least one selected from light absorbing organics and inorganics.
  • the light absorbing organic material may be at least one selected from an organic semiconductor material and a phosphorescent material, and the light absorbing inorganic material may be an inorganic semiconductor material.
  • the nano-aggregate may be at least one selected from an inorganic semiconductor material, a combination of an organic semiconductor material and a phosphor, and a combination of an organic semiconductor material and an inorganic semiconductor material.
  • a first electrode is formed on a substrate, and a light absorption layer having irregularities on a surface thereof is formed on the first electrode, and an electron transport layer is formed on the light absorption layer. And forming a second electrode on the electron transport layer.
  • the method may further include forming an electron injection layer between forming the second electrode on the electron transport layer.
  • Forming a light absorption layer having irregularities on the surface on the first electrode preparing a mixed solution containing a good solvent, a light absorbing material, a poor solvent, agitated the mixed solution to form a nano-aggregate spontaneously
  • Obtaining a composition applying a composition containing the nano-aggregate on the first electrode and the heat treatment of the applied composition may be included.
  • Applying the composition containing the nano-aggregate on the first electrode may be carried out through any one selected from spin coating, spray coating, dip coating, screen printing, inkjet printing, gravure printing and offset printing.
  • the nano-aggregates are formed on the surface according to the difference in solubility in the good and poor solvents of light-absorbing organic and / or inorganic materials, thereby reducing the recombination of excitons, thereby increasing the efficiency of transporting charges to the anode and the cathode. can do.
  • the solar cell including the light absorbing layer irregularities are spontaneously formed on the surface of the light absorbing layer regularly, thereby suppressing total reflection of incident sunlight, thereby reducing light loss and increasing the light absorbing area to increase photoelectric conversion efficiency. Can be improved.
  • the manufacturing method of the solar cell is easy to control the process conditions, it is possible to optimize the photoelectric conversion efficiency in consideration of the light absorption amount and the self-resistance of the solar cell, it is possible to manufacture a high efficiency solar cell simply and inexpensively.
  • FIG. 1A and 1B are perspective views of a solar cell according to an embodiment of the present invention.
  • FIG. 2 is a flowchart illustrating a method of manufacturing a light absorption layer for a solar cell according to an embodiment of the present invention.
  • 3A to 3D are process diagrams illustrating a method of manufacturing a light absorption layer for a solar cell according to an embodiment of the present invention.
  • 4A to 4F are AFM images of the surface of the light absorption layer manufactured according to one embodiment of the present invention.
  • 5A to 5D are process diagrams illustrating a method of manufacturing a solar cell according to an embodiment of the present invention.
  • FIG. 6 is an energy band diagram of a solar cell according to an embodiment of the present invention.
  • FIG. 7 is a graph showing the I-V curve of the solar cell according to an embodiment of the present invention.
  • a layer is referred to herein as "on" another layer or substrate, it may be formed directly on the other layer or substrate, or a third layer may be interposed therebetween.
  • the directional expression of the upper part, the upper part, and the upper part may be understood as meanings of the lower part, the lower part, the lower part, and the like according to the criteria.
  • the expression of the spatial direction should be understood as a relative direction and should not be construed as limiting the absolute direction.
  • FIG. 1A and 1B are perspective views of a solar cell according to an embodiment of the present invention.
  • the first electrode 100 may be positioned on a substrate (not shown).
  • the substrate is used to support the device and can be removed as needed.
  • the substrate may be a transparent inorganic substrate.
  • the substrate may be selected from glass, quartz, Al 2 O 3 and SiC.
  • the substrate may be a transparent organic substrate.
  • the substrate may be selected from polyethylene terephthlate (PET), polyethersulfone (PES), polystyrene (PS), polycarbonate (PC), polyimide (PI), polyethylene naphthalate (PEN), and polyarylate (PAR).
  • the first electrode 100 serves as an anode for collecting holes generated in the light absorption layer 300 to be described later.
  • the first electrode 100 may be made of a conductive material having a low resistance and having a transparency to transmit light.
  • the first electrode 100 is carbon nanotube (CNT), graphene, ITO, doped ZnO (AZO: Al doping, GZO: Ga doping, IZO: In doping, IGZO: In and Ga doping, MZO: Mg doped), MgO doped with Al or Ga, In 2 O 3 doped with Sn, SnO 2 doped with F, or TiO 2 doped with Nb.
  • CNT carbon nanotube
  • ITO doped ZnO
  • GZO Ga doping
  • IZO In doping
  • IGZO In and Ga doping
  • MZO Mg doped
  • MgO doped with Al or Ga In 2 O 3 doped with Sn
  • SnO 2 doped with F or TiO 2 doped with Nb.
  • the light absorbing layer 300 absorbs the irradiated light and forms an electron-hole pair, that is, an exciton, in an excited state.
  • the light absorbing layer 300 has a structure in which the thin film layer 310 is disposed below and the nanoaggregates 330 are arranged on the thin film layer 310. Therefore, the light absorption layer 300 forms an uneven structure on the surface due to the nano-aggregates 330.
  • the uneven structure may be spontaneously formed by a difference in solubility resulting from dissolving in a solvent (good solvent) that dissolves light absorbing material well and a solvent (poor solvent) that does not dissolve well.
  • the thin film layer 310 positioned below the light absorbing layer 300 includes a light absorbing material evenly dissolved in a good solvent, and the nano-aggregates 330 on the upper side cause the light absorbing material to aggregate in a poor solvent. Is formed.
  • the light absorbing material may be selected from at least one of a light absorbing organic material and an inorganic material.
  • the light absorbing organic material may be at least one selected from organic semiconductor materials and phosphorescent materials.
  • the light absorbing inorganic material may be an inorganic semiconductor material including a quantum dot having a single structure or a dual structure of a core-shell.
  • the light absorbing organic material may be pentacene, PDCDT, PenPTC, ZnPC, CuPC, TiOPC, Coumarin 6, P3HT, P3KT, PT, PTCBI, ADIDI, PTCDA, PTCDI, Spiro-MeOTAD, NTDA, MePTC, HepPTC, At least one selected from the group consisting of F16CuPC, P3OT, MEH-PPV, MDMO-PPV, PFO, PFO-DMP, SubPc, N3, and PBDTTT, and compounds of the Ir, Pt, Eu, or Tb family.
  • the light absorption inorganic material is MgO, MgS, MgSe, MgTe, CaO, CaS, CaSe, CaTe, SrO, SrS, SrSe, SrTe, BaO, BaS, BaSe, BaTE, ZnO, Cu 2 O, ZnS, ZnSe, ZnTe , CdO, CdS, CdSe, CdTe, HgO, HgS, HgSe, HgTe, Al 2 S 3 , Al 2 Se 3 , Al 2 Te 3 , Ga 2 O 3 , Ga 2 S 3 , Ga 2 Se 3 , Ga 2 Te 3 , In 2 O 3 , In 2 S 3 , In 2 Se 3 , In 2 Te 3 , GeO 2 , SnO 2 , SnS, SnSe, SnTe, PbO, Pb O 2, PbS, PbSe, PbTe, AlN, AlP, At least
  • the nano-aggregate 330 may be any one selected from an inorganic semiconductor material, a combination of an organic semiconductor material and a phosphor material, and a combination of an organic semiconductor material and an inorganic semiconductor material.
  • the phosphorescent material or the inorganic semiconductor material combined with the organic semiconductor material may have a nanoparticle form.
  • the nano-aggregate 330 is a combination of an organic semiconductor material and a phosphor material or a combination of an organic semiconductor material and an inorganic semiconductor material, since the phosphor or inorganic semiconductor material in the form of nanoparticles has an excellent light absorption rate, A number of excitons can be produced to increase the photocurrent.
  • triplet excitons with increased diffusion distances can be formed, allowing a greater number of excitons to be separated at the interface.
  • the uneven structure of the light absorption layer 300 increases the area of the interface capable of separating excitons, thereby reducing the recombination rate of the charge. Therefore, the photocurrent can be increased to improve the photoelectric conversion efficiency.
  • the electron transport layer 400 is located on the light absorbing layer 300.
  • the electron transport layer 400 performs a function of capturing electrons in electrons and holes separated at an interface between the light absorption layer 300 and the electron transport layer 400 and transporting the electrons to the second electrode 600.
  • the electron transport layer 400 may contain an organic material or an inorganic material.
  • the electron transport layer 400 is fullerene (C60, C70, C80) or a fullerene derivative PCBM ([6,6] -phenyl-C61 butyric acid methyl ester) (PCBM (C60), PCBM (C70), PCBM ( C80)).
  • the electron transport layer 400 may contain an inorganic material including ZnO, TiO 2 , SnO 2 or carbon nanotubes.
  • the second electrode 600 is located on the electron transport layer 400.
  • the second electrode 600 serves as a cathode for collecting electrons generated in the light absorption layer 300.
  • the second electrode 600 may contain a metal, an alloy, an electrically conductive compound, and a mixture thereof having a small work function.
  • the second electrode 600 may contain any one selected from Al, Au, Cu, Pt, Ag, W, Ni, Zn, Ti, Zr, Hf, Cd, Pd, and alloys thereof.
  • the second electrode 600 may include CuAlO 2 / Ag / CuAlO 2 , ITO / Ag / ITO, ZnO / Ag / ZnO, ZnS / Ag / ZnS, TiO 2 / Ag / TiO 2 , ITO / Au / ITO, It may contain any one selected from WO 3 / Ag / WO 3 and MoO 3 / Ag / MoO 3 .
  • the second electrode 600 may contain any one selected from graphene, carbon nanotubes, conductive polymers, and composites thereof. In particular, when the second electrode 600 is formed of a transparent organic electrode, light reception may be possible even from above.
  • a hole transport layer (HTL) 200 and an electron injection layer 500 may be further included in the configuration of FIG. 1A. Since the description of the components other than the hole transport layer 200 and the electron injection layer 500 is the same as in FIG. 1A, it will be omitted.
  • the hole transport layer 200 may be interposed between the first electrode 100 and the light absorption layer 300.
  • the electron injection layer 500 may be interposed between the electron transport layer 400 and the second electrode 600.
  • the hole transport layer 200 is positioned between the first electrode 100 and the light absorbing layer 300 so as to easily transport holes generated in the light absorbing layer 300 to the first electrode 100.
  • the hole transport layer 200 is preferably made of a compound having excellent hole blocking ability as well as electron blocking properties and thin film formation ability.
  • the hole transport layer 200 may include PEDOT (poly (3,4-ethylenedioxythiophene)), PSS (poly (styrenesulfonate)), polyaniline, phthalocyanine, pentacene, polydiphenyl, acetylene and derivatives thereof At least one conductive polymer such as NPB, TPD, Spiro-TPD, Spiro-NPB, DMFL-TPD, DMFL-NPB, DPFL-TPD, DPFL-NPB, Spiro-TAD, BPAPF, NPAPF, NPBAPF, Spiro-2NPB , PAPB, 2,2'-Spiro-DBP, Spiro-BPA, TAPC, Spiro-TTB or may contain organic substances such as HMTPD, but is not limited thereto. More preferably, the hole transport layer 200 may contain a mixture of PEDOT: PSS (poly (3,4-ethylenedioxythiophene): poly (styrenesulf
  • the electron injection layer 500 is positioned between the electron transport layer 400 and the second electrode 600 to improve electron injection.
  • the electron injection layer 500 may be an insulating film having a thin thickness.
  • the electron injection layer 500 may include LiF, Liq, TPBi, PBD, BCP, Bphen, BAlq, Bpy-OXD, BP-OXD-Bpy, TAZ, NTAZ, NBphen, Bpy-FOXD, OXD-7l, 3TPYMB, It may contain any one selected from 2-NPIP, PADN, HNBphen, POPy2, BP4mPy, TmPyPB and BTB.
  • FIG. 2 is a flowchart illustrating a method of manufacturing a light absorption layer of a solar cell according to an embodiment of the present invention.
  • 3A to 3D are process diagrams illustrating a method of manufacturing a light absorption layer of a solar cell according to an embodiment of the present invention.
  • the light absorbing material 310a may be selected from at least one of a light absorbing organic material and a light absorbing inorganic material.
  • the good solvent 340 may refer to a solvent having excellent solubility of the light absorbing material 310a. Therefore, the good solvent 340 preferably has the same polarity as that of the light absorbing material 310a.
  • organic material P3HT poly (3-hexylthiophen)
  • chlorobenzene or dichlorobenzene may be used as the good solvent 340.
  • the poor solvent 350 may refer to a solvent having low solubility of the light absorbing material 310a. Therefore, the poor solvent 350 preferably has a polarity different from that of the light absorbing material 310a.
  • the poor solvent 350 may be added in a constant volume ratio with respect to the good solvent 340, which may be set differently according to experimental conditions.
  • P3HT poly (3-hexylthiophen)
  • PGMEA propylene glycol mono-methyl ether acetate
  • the mixed solution may include a light absorbing organic material or a light absorbing inorganic material having a form of nanoparticles 320.
  • the light absorbing organic material or the light absorbing inorganic material in the form of the nanoparticle 320 may be a phosphor or an inorganic semiconductor material.
  • the inorganic semiconductor material may be a quantum dot having a single structure or a dual structure of a core-shell.
  • the phosphor or quantum dot in the form of nanoparticles 320 has an excellent light absorption, there is an advantage that a greater number of excitons are generated to increase the photocurrent.
  • a good solvent-poor solvent may be used in various combinations for various kinds of light absorbing materials 310a.
  • the nano-aggregate 330 is formed by stirring the mixed solution including the good solvent 340, the light absorbing material 310a, the poor solvent 350, and the light absorbing nanoparticle 320.
  • a portion of the light absorbing material 310a and the light absorbing nanoparticles 320 that are dissolved in the good solvent 340 through the stirring may move to the poor solvent 350, and the nanoaggregate 330 may be formed.
  • the nanoaggregate 330 has a shape in which the nanoparticle 320 surrounds the light absorbing material 310a.
  • the size of the nano-aggregate 330 can be controlled by adjusting the concentration of the solvent, the stirring time, the coating speed and the time.
  • the composition including the nano-aggregate 330 is coated on the electrode or the organic thin film layer (S300).
  • the electrode may be the first electrode 100
  • the organic thin film layer may be the hole transport layer 200.
  • the coating may be carried out by appropriately selecting a coating or printing method such as spin coating, spray coating, dip coating, screen printing, inkjet printing, gravure printing, offset printing, etc. as necessary.
  • a coating or printing method such as spin coating, spray coating, dip coating, screen printing, inkjet printing, gravure printing, offset printing, etc. as necessary.
  • the coated composition is heat-treated to form a light absorption layer 300.
  • the heat treatment may be carried out at a temperature range of 20 °C to 80 °C for 10 to 30 minutes.
  • the light absorbing material 310 remaining in the good solvent 340 through the coating and heat treatment may be formed as a thin film layer 310 at the bottom.
  • the nano-aggregate 330 may be deposited on the thin film layer 310. Therefore, the light absorption layer 300 has a concave-convex structure on the surface due to the nano-aggregates 330 arranged thereon.
  • 4A to 4F are AFM images of the surface of the light absorption layer manufactured according to one embodiment of the present invention.
  • 4A and 4B are AFM images of nano-aggregates formed using P3HT (poly (3-hexylthiophen)), which is a light absorbing organic material, as a light absorbing material and using PGMEA (propylene glycol mono-methyl ether acetate) as a poor solvent.
  • 4C and 4D are AFM images of nano-aggregates formed using ZnSe / InP / ZnS, which are light absorbing inorganic materials, as light absorbing materials and using propylene glycol mono-methyl ether acetate (PGMEA) as a poor solvent.
  • 4F shows nanoparticles formed using P3HT (poly (3-hexylthiophen), a light absorbing organic material, as a light absorbing material, ZnSe, an inorganic nanoparticle, and PGMEA (propylene glycol monomethyl ether acetate) as a poor solvent.
  • P3HT poly (3-hexylthiophen
  • ZnSe zinc absorbing material
  • PGMEA propylene glycol monomethyl ether acetate
  • nanoaggregates having a length of about 3 nm to 25 nm are densely or densely arranged according to the type of light absorbing material and the presence or absence of light absorbing material in the form of nanoparticles to form an uneven structure.
  • the size of the nano-aggregates can be controlled by adjusting the concentration of the solvent, the stirring time, the application rate and time.
  • 5A to 5D are process diagrams illustrating a method of manufacturing a solar cell according to an embodiment of the present invention.
  • a hole transport layer 200 is formed on a substrate (not shown) on which the first electrode 100 is formed.
  • the first electrode 100 may be made of a transparent conductive metal oxide and various carbon materials.
  • the first electrode 100 may be formed on the substrate by using thermal image deposition, electron beam deposition, RF sputtering or magnetron sputtering.
  • the hole transport layer 200 may contain a conductive polymer material.
  • the hole transport layer 200 may be formed using spin coating, spray coating, dipping, sputtering, vacuum deposition, or the like.
  • the light absorption layer 300 is formed on the hole transport layer 200.
  • the light absorption layer 300 may be formed of a thin film layer 310 disposed below and a nano-aggregate 330 arranged thereon.
  • the method of manufacturing the light absorbing layer 300 is the same as described with reference to FIGS. 2 and 3A to 3D, detailed descriptions thereof will be omitted.
  • the electron transport layer 400 is formed on the light absorption layer 300.
  • the electron transport layer 400 may include an organic material or an inorganic material.
  • the electron transport layer 400 may be formed using a solution process.
  • the electron transport layer 400 may be formed using vacuum deposition, spin coating, dip coating, drop coating, spray coating, inkjet printing or screen printing. At this time, it may be formed in an appropriate thickness in consideration of the type and characteristics of the organic material or inorganic material used.
  • a second electrode 600 is formed on the electron transport layer 300.
  • a thin thickness electron injection layer 500 may be further formed to smoothly inject electrons.
  • the electron injection layer 500 is preferably formed of a thin thin film having an insulating property, such as LiF, Liq.
  • the second electrode 600 may be formed to contain various carbon materials and conductive polymer materials, in addition to a metal or an alloy having excellent conductivity. In particular, when the second electrode 600 is formed of a transparent organic electrode, light reception may be possible even from above.
  • the electron injection layer 500 may be formed using vacuum deposition, spin coating, dip coating, drop coating, spray coating, inkjet printing or screen printing.
  • the second electrode 600 may be formed using a thermal image deposition, electron beam deposition, RF sputtering or magnetron sputtering method.
  • ITO transparent electrode was formed on the glass substrate by spin coating, and then ultrasonically washed to remove impurities from the surface of the substrate.
  • the light absorption layer was formed on the PEDOT: PSS hole transport layer.
  • the formation process is as follows.
  • compositions of Samples 1, 2 and 3 were spin-coated on a PEDOT: PSS hole transport layer and heat treated to form a light absorption layer having a planar or uneven structure.
  • FIG. 6 is an energy band diagram of a solar cell according to an embodiment of the present invention.
  • sunlight is absorbed by the light absorbing layer 300, and the light absorbing layer 300 absorbs light energy from sunlight to generate excitons.
  • the generated excitons move and diffuse, and are separated into electrons and holes at the bonding interface between the light absorption layer 300 and the electron transport layer 400.
  • the separated electrons move to the second electrode 600 through the energy level of the electron transport layer 400, and the separated holes move to the first electrode 100 through the energy level of the hole transport layer 200.
  • the charges collected in the first electrode 100 and the second electrode 600 form a photocurrent.
  • FIG. 7 is a graph showing the I-V curve of the solar cell according to an embodiment of the present invention.
  • the short circuit current (J sc ) has a value of 6.2 mAcm ⁇ 2
  • Sample 2 and Sample 3 formed of the uneven structure
  • the values of 7.5 mAcm -2 and 8.6 mAcm -2 respectively. That is, it can be seen that the short-circuit current increased in the solar cell formed of the uneven structure surface.
  • the photovoltaic conversion efficiency ( ⁇ ) of the sample 1 was only 0.8%
  • the uneven structure had values of 1.18% and 1.59%, respectively, and it was confirmed that the solar cell increased significantly.

Abstract

Provided are a method for preparing a light absorption layer for a solar cell, a solar cell including the light absorption layer, and a manufacturing method thereof.The method for preparing a light absorption layer for a solar cell can increase the transport efficiency of charges moving to positive and negative electrodes through the reduction of exciton recombination by spontaneously forming nano aggregates due to a solubility difference of a light absorption material in a good solvent and a poor solvent. In addition, the solar cell can improve photocurrent and photoelectric conversion efficiency by increasing the area of a bonded interface between the light absorption layer and an electron transport layer through the formation of an uneven structure on the surface of the light absorption layer due to the arrangement of the nano aggregates. Furthermore, the method for manufacturing the solar cell can simply and easily manufacture a large-sized high efficiency solar cell using a solution process.

Description

태양전지용 광흡수층의 제조방법, 광흡수층을 포함하는 태양전지 및 이의 제조방법Method for manufacturing light absorbing layer for solar cell, solar cell comprising light absorbing layer and method for manufacturing same
본 발명은 태양전지용 광흡수층의 제조방법, 광흡수층을 포함하는 태양전지 및 이의 제조방법에 관한 것으로, 보다 상세하게는 양용매(good solvent) 및 빈용매(poor solvent)를 이용하여 자발적으로 표면에 요철을 형성하는 태양전지용 광흡수층의 제조방법, 광흡수층을 포함한 태양전지 및 이의 제조방법에 관한 것이다.The present invention relates to a method for manufacturing a light absorbing layer for a solar cell, a solar cell including the light absorbing layer, and a method for manufacturing the same, and more particularly, using a good solvent and a poor solvent on a surface voluntarily. The present invention relates to a method for manufacturing a light absorbing layer for solar cells that forms irregularities, a solar cell including the light absorbing layer, and a method for manufacturing the same.
최근 심각한 환경오염 문제와 화석 에너지 고갈로 차세대 청정 에너지 개발에 대한 중요성이 증대되고 있다. 이중에서도 태양전지는 공해가 적고, 자원이 무한하며, 반영구적으로 사용할 수 있어, 에너지 문제를 해결할 수 있는 차세대 에너지원으로 각광받고 있다.Recently, the importance of developing the next generation of clean energy is increasing due to serious environmental pollution and depletion of fossil energy. Among them, solar cells are spotlighted as next-generation energy sources that can solve energy problems because they have less pollution, infinite resources, and can be used semi-permanently.
태양전지는 광기전력 효과(Photovoltaic effect)를 이용하여 빛 에너지를 직접 전기 에너지로 변환시키는 반도체 소자이다. 상기 태양전지는 광활성층의 물질에 따라 크게 무기 태양전지(inorganic solar cell), 염료감응 태양전지(dye-sensitized solar cell) 및 유기 태양전지(organic solar cell)로 구분될 수 있다. 이중에서도, 무기 태양전지의 일종인 실리콘 계열 태양전지는 광전 변환효율이 한계치에 도달하고, 갑작스러운 수요 증가에 따라 실리콘 원자재 수급이 어려워지는 등 여러 문제점에 직면하고 있다. 따라서, 이에 대한 대안으로서 유기 태양전지에 대한 활발한 연구가 진행되고 있다.Solar cells are semiconductor devices that convert light energy directly into electrical energy using the photovoltaic effect. The solar cell may be broadly classified into an inorganic solar cell, an dye-sensitized solar cell, and an organic solar cell according to the material of the photoactive layer. Among them, silicon-based solar cells, which are a kind of inorganic solar cells, face various problems such as photoelectric conversion efficiency reaching a limit and supply of silicon raw materials becomes difficult due to sudden increase in demand. Therefore, active researches on organic solar cells have been conducted as an alternative.
유기 태양전지는 유기물 박막을 적층하여 제조되므로, 유연한 기판을 사용할 수 있고, 무기 태양전지에 비해 다양한 구조로 제조 가능하다. 또한, 광흡수층으로 사용되는 유기 분자의 흡광 계수가 높아, 약 100nm 정도의 미세 박막으로도 태양광을 충분히 흡수할 수 있다. 따라서, 유기 태양전지는 저비용으로 간단하게 미세 소자로 제조할 수 있으며, 유기물의 특성상 굽힘성 및 가공성이 우수하여 다양한 분야로 응용이 가능한 이점이 있다.Since the organic solar cell is manufactured by stacking an organic thin film, a flexible substrate can be used, and the organic solar cell can be manufactured in various structures compared to the inorganic solar cell. In addition, the absorption coefficient of the organic molecules used as the light absorption layer is high, and even a fine thin film of about 100 nm can sufficiently absorb sunlight. Therefore, the organic solar cell can be easily manufactured as a micro device at low cost, and has excellent advantages in bending property and workability due to the characteristics of the organic material, and can be applied to various fields.
유기 태양전지는 전자 주개(electron donor: D) 및 전자 받개(electron acceptor: A)의 접합 구조로 이루어진다. 유기 태양전지에 광을 조사하면 광은 흡수되어 여기 상태의 전자-정공 쌍, 즉, 엑시톤(exciton)을 형성한다. 상기 엑시톤은 임의 방향으로 확산하다가 D-A 계면(interface)을 만나면 전자와 정공으로 분리된다. 그러나, 엑시톤이 재결합하여 소멸되기까지 걸리는 시간은 100 ps(피코초)로 매우 짧기 때문에, 엑시톤이 재결합 없이 확산될 수 있는 거리는 약 10nm 내외라고 알려져 있다. 따라서, 엑시톤이 재결합 없이 분리되어 전자와 정공을 생성하기 위해서는 상기 엑시톤이 D-A 접합 계면에서 10 nm 이내에 형성되어야 한다. The organic solar cell has a junction structure of an electron donor (D) and an electron acceptor (A). When the organic solar cell is irradiated with light, the light is absorbed to form an electron-hole pair, that is, an exciton, in an excited state. The excitons diffuse in an arbitrary direction and are separated into electrons and holes when they meet the D-A interface. However, since the time taken for the exciton to recombine and disappear is very short, 100 ps (picoseconds), the distance that the exciton can diffuse without recombination is known to be about 10 nm. Therefore, in order for the excitons to be separated without recombination to generate electrons and holes, the excitons must be formed within 10 nm at the D-A junction interface.
그러나, 종래의 유기 태양전지는 엑시톤의 확산거리가 짧기 때문에 광전 변환효율이 매우 낮은 점이 한계로 지적되어 왔다. However, the conventional organic solar cell has been pointed out that the photoelectric conversion efficiency is very low because the exciton diffusion distance is short.
상기의 문제점을 해결하기 위하여 전자와 정공으로 분리되기 위한 엑시톤의이동거리를 감소시키거나, D-A 접합 계면의 면적을 확장시키는 방안이 강구되었다. In order to solve the above problems, a method of reducing excitons traveling distance or expanding the area of the D-A junction interface for separating electrons and holes has been devised.
엑시톤의 이동거리를 감소시키기 위해 광활성층의 두께를 얇게 할 수 있다. 그러나, 이 경우, 광흡수량이 감소하게 되어 광전 변환효율이 떨어지는 단점이 있었다.The thickness of the photoactive layer can be made thin to reduce the exciton travel distance. However, in this case, the amount of light absorption decreases and thus the photoelectric conversion efficiency is lowered.
한편, D-A 접합 계면의 면적을 확장하기 위하여 대한민국 등록특허 제10-0959760호에는 양극산화 알루미늄(AAO)을 나노 다공성 템플레이트로 사용하여 나노 막대를 형성하는 기술이 개시되어 있다. 또한, 대한민국 공개특허 제10-2011-0068216호에는 LPCVD법, PECVD법, 열선 화학 기상 증착 (hot chemical vapor deposition)법과 같은 화학 기상 증착법 (chemical vapor deposition; CVD) 및 화학적 건식 식각을 통하여 광활성층에 다수 개의 나노 막대로 구성된 광전변환층 패턴을 형성하는 기술이 개시되어 있다. Meanwhile, in order to expand the area of the D-A junction interface, Korean Patent No. 10-0959760 discloses a technique of forming a nano bar using aluminum anodized oxide (AAO) as a nanoporous template. In addition, Korean Patent Publication No. 10-2011-0068216 discloses a photoactive layer through chemical vapor deposition (CVD) and chemical dry etching such as LPCVD, PECVD, and hot chemical vapor deposition. A technique for forming a photoelectric conversion layer pattern composed of a plurality of nanorods is disclosed.
그러나, 상기의 방법들은 주로 화학적인 방법을 사용하여 나노 막대를 성장시키기 때문에 그 구조상 불순물이 다수 포함될 수 있다. 상기 불순물은 엑시톤의 확산을 방해하거나 재결합을 유도하여 광전 변환효율을 떨어뜨리는 문제점이 있다. 또한, 상기 방법들은 수행 장비 가격이 고가이고, 고진공이 요구되어 제조 단가가 높은 문제점이 있었다. However, since the above methods mainly grow the nanorods using chemical methods, many of the structural impurities may be included. The impurities hinder the diffusion of excitons or induce recombination, thereby degrading photoelectric conversion efficiency. In addition, the above methods have a problem in that the cost of performing equipment is high, and high vacuum is required, resulting in high manufacturing costs.
본 발명이 해결하고자 하는 과제는, 엑시톤의 재결합을 감소시켜 양극 및 음극으로 이동하는 전하의 수송 효율을 높이는 태양전지의 광흡수층 제조방법을 제공하는 데 있다.An object of the present invention is to provide a method for manufacturing a light absorption layer of a solar cell to reduce the recombination of excitons to increase the transport efficiency of the charge to move to the anode and cathode.
본 발명이 해결하고자 하는 과제는, 광흡수층의 표면 내에 요철을 구비하여 광전 변환효율이 개선된 태양전지를 제공하는 데 있다. An object of the present invention is to provide a solar cell having improved photoelectric conversion efficiency by providing irregularities in the surface of the light absorption layer.
본 발명이 해결하고자 하는 과제는, 용액 공정을 사용하여 공정 조건의 조절이 간단하고, 제조 비용이 저렴한 태양전지의 제조방법을 제공하는 데 있다. The problem to be solved by the present invention is to provide a method for manufacturing a solar cell is easy to control the process conditions using a solution process, and low manufacturing cost.
상기 과제를 이루기 위하여 본 발명의 일 측면은 양용매, 빈용매 및 광흡수 물질이 포함된 혼합 용액을 준비하는 단계, 상기 혼합 용액을 교반하여 나노응집체가 자발 형성된 조성물을 수득하는 단계, 상기 나노응집체가 포함된 조성물을 태양전지용 전극 또는 유기 박막층 상에 도포하는 단계 및 상기 도포된 조성물을 열처리하여 요철 구조를 가지는 광흡수층을 형성하는 단계를 포함한다.One aspect of the present invention to achieve the above object is to prepare a mixed solution containing a good solvent, poor solvent and light absorbing material, agitating the mixed solution to obtain a spontaneously formed nano-aggregate, the nano-aggregate It comprises the step of applying a composition containing a solar cell electrode or an organic thin film layer and the heat treatment of the applied composition to form a light absorption layer having a concave-convex structure.
상기 광흡수 물질은 광흡수 유기물 및 광흡수 무기물 중에서 선택되는 적어도 하나일 수 있다. 상기 광흡수 유기물은 유기 반도체 물질 및 인광 물질 중에서 선택되는 적어도 하나일 수 있다. 상기 광흡수 무기물은 무기 반도체 물질일 수 있다.The light absorbing material may be at least one selected from a light absorbing organic material and a light absorbing inorganic material. The light absorbing organic material may be at least one selected from organic semiconductor materials and phosphorescent materials. The light absorbing inorganic material may be an inorganic semiconductor material.
상기 양용매 및 상기 빈용매 중 어느 하나는 클로로벤젠, 디클로로벤젠, 클로로포름, 톨루엔 및 헥산으로 구성되는 군으로부터 선택되고, 나머지 하나는 PGMEA, 에틸렌 글리콜, 테트라에톡시실란, 디부틸 에테르, 디메틸포름아미드, 자일렌, 물, 메탄올, 에탄올 및 프로판올로 구성되는 군으로부터 선택될 수 있다.One of the good solvent and the poor solvent is selected from the group consisting of chlorobenzene, dichlorobenzene, chloroform, toluene and hexane, and the other is PGMEA, ethylene glycol, tetraethoxysilane, dibutyl ether, dimethylformamide , Xylene, water, methanol, ethanol and propanol.
상기 나노응집체는 무기 반도체 물질, 유기 반도체 물질과 인광 물질의 조합 및 유기 반도체 물질과 무기 반도체 물질의 조합 중에서 선택되는 적어도 하나일 수 있다.The nano-aggregate may be at least one selected from an inorganic semiconductor material, a combination of an organic semiconductor material and a phosphor, and a combination of an organic semiconductor material and an inorganic semiconductor material.
상기 나노응집체가 포함된 조성물을 태양전지용 전극 또는 유기 박막층 상에 도포하는 단계는 스핀 코팅, 스프레이 코팅, 딥 코팅, 스크린 프린팅, 잉크젯 프린팅, 그라비아 프린팅 및 오프셋 프린팅 중 어느 하나를 통해 수행될 수 있다.Applying the composition containing the nano-aggregate on the solar cell electrode or the organic thin film layer may be carried out by any one of spin coating, spray coating, dip coating, screen printing, inkjet printing, gravure printing and offset printing.
상기 과제를 이루기 위하여 본 발명의 일 측면은 제1 전극, 상기 제1 전극 상에 형성되며, 광흡수 물질을 포함하는 광흡수층, 상기 광흡수층 상에 형성된 전자 수송층 및 상기 전자 수송층 상에 형성된 제2 전극을 포함하고, 상기 광흡수층은 하부 박막층의 상부에 수직방향으로 돌출 형성된 나노응집체들이 배열되어 요철을 형성하며, 상기 전자 수송층은 상기 나노응집체들 사이의 공간을 채우며 상기 나노응집체들을 덮도록 형성된다.One aspect of the present invention for achieving the above object is a first electrode, a light absorption layer formed on the first electrode, including a light absorbing material, an electron transport layer formed on the light absorbing layer and the second formed on the electron transport layer And an electrode, wherein the light absorbing layer is formed with nanoaggregates protruding in a vertical direction on top of the lower thin film layer to form irregularities, and the electron transport layer fills the space between the nanoaggregates and covers the nanoaggregates. .
상기 제1 전극과 상기 광흡수층 사이에 개재되는 정공 수송층을 더 포함하고, 상기 전자 수송층과 상기 제2 전극 사이에 개재되는 전하 주입층을 더 포함할 수 있다.The display device may further include a hole transport layer interposed between the first electrode and the light absorption layer, and further include a charge injection layer interposed between the electron transport layer and the second electrode.
상기 광흡수 물질은 광흡수 유기물 및 무기물 중에서 선택되는 적어도 어느 하나일 수 있다. 상기 광흡수 유기물은 유기 반도체 물질 및 인광 물질 중에서 선택되는 적어도 하나이고, 상기 광흡수 무기물은 무기 반도체 물질일 수 있다.The light absorbing material may be at least one selected from light absorbing organics and inorganics. The light absorbing organic material may be at least one selected from an organic semiconductor material and a phosphorescent material, and the light absorbing inorganic material may be an inorganic semiconductor material.
상기 나노응집체는 무기 반도체 물질, 유기 반도체 물질과 인광 물질의 조합 및 유기 반도체 물질과 무기 반도체 물질의 조합 중에서 선택되는 적어도 하나일 수 있다.The nano-aggregate may be at least one selected from an inorganic semiconductor material, a combination of an organic semiconductor material and a phosphor, and a combination of an organic semiconductor material and an inorganic semiconductor material.
상기 과제를 이루기 위하여 본 발명의 일 측면은 기판 상에 제1 전극을 형성하는 단계, 상기 제1 전극 상에, 표면에 요철을 가지는 광흡수층을 형성하는 단계, 상기 광흡수층 상에 전자 수송층을 형성하는 단계 및 상기 전자 수송층 상에 제2 전극을 형성하는 단계를 포함한다.According to an aspect of the present invention, a first electrode is formed on a substrate, and a light absorption layer having irregularities on a surface thereof is formed on the first electrode, and an electron transport layer is formed on the light absorption layer. And forming a second electrode on the electron transport layer.
상기 기판 상에 제1 전극을 형성하는 단계와, 상기 제1 전극 상에 광흡수층을 형성하는 단계 사이에 정공 수송층을 형성하는 단계를 더 포함하고, 상기 광흡수층 상에 전자 수송층을 형성하는 단계와 상기 전자 수송층 상에 제2 전극을 형성하는 단계 사이에 전자 주입층을 형성하는 단계를 더 포함할 수 있다.Forming a hole transport layer between forming a first electrode on the substrate and forming a light absorption layer on the first electrode, and forming an electron transport layer on the light absorption layer; The method may further include forming an electron injection layer between forming the second electrode on the electron transport layer.
상기 제1 전극 상에, 표면에 요철을 가지는 광흡수층을 형성하는 단계는, 양용매, 광흡수 물질, 빈용매가 포함된 혼합 용액을 준비하는 단계, 상기 혼합 용액을 교반하여 나노응집체가 자발 형성된 조성물을 수득하는 단계, 상기 나노응집체가 포함된 조성물을 제1 전극 상에 도포하는 단계 및 상기 도포된 조성물을 열처리하는 단계를 포함할 수 있다.Forming a light absorption layer having irregularities on the surface on the first electrode, preparing a mixed solution containing a good solvent, a light absorbing material, a poor solvent, agitated the mixed solution to form a nano-aggregate spontaneously Obtaining a composition, applying a composition containing the nano-aggregate on the first electrode and the heat treatment of the applied composition may be included.
상기 나노응집체가 포함된 조성물을 제1 전극 상에 도포하는 단계는 스핀 코팅, 스프레이 코팅, 딥 코팅, 스크린 프린팅, 잉크젯 프린팅, 그라비아 프린팅 및 오프셋 프린팅 중에서 선택되는 어느 하나를 통해 수행될 수 있다.Applying the composition containing the nano-aggregate on the first electrode may be carried out through any one selected from spin coating, spray coating, dip coating, screen printing, inkjet printing, gravure printing and offset printing.
본 발명에 따르면, 광흡수 유기물 및/또는 무기물의 양용매와 빈용매에서의 용해도 차이에 따라 나노응집체가 표면에 형성되어, 엑시톤의 재결합을 감소시킴으로 양극 및 음극으로 이동하는 전하의 수송 효율이 증가할 수 있다.According to the present invention, the nano-aggregates are formed on the surface according to the difference in solubility in the good and poor solvents of light-absorbing organic and / or inorganic materials, thereby reducing the recombination of excitons, thereby increasing the efficiency of transporting charges to the anode and the cathode. can do.
또한, 광흡수층을 포함하는 태양전지는 광흡수층의 표면에 요철 구조가 규칙적으로 자발 형성되어, 입사된 태양광의 전반사를 억제하므로, 광손실을 줄일 수 있으며, 광흡수 면적을 증가시켜 광전 변환효율을 향상시킬 수 있다.In addition, in the solar cell including the light absorbing layer, irregularities are spontaneously formed on the surface of the light absorbing layer regularly, thereby suppressing total reflection of incident sunlight, thereby reducing light loss and increasing the light absorbing area to increase photoelectric conversion efficiency. Can be improved.
그리고, 태양전지의 제조방법은 공정 조건의 조절이 용이하여 광흡수량 및 태양전지의 자체 저항을 고려한 광전 변환효율의 최적화가 가능하며, 간단하고 저렴하게 고효율의 태양전지를 제조할 수 있다.In addition, the manufacturing method of the solar cell is easy to control the process conditions, it is possible to optimize the photoelectric conversion efficiency in consideration of the light absorption amount and the self-resistance of the solar cell, it is possible to manufacture a high efficiency solar cell simply and inexpensively.
본 발명의 기술적 효과들은 이상에서 언급한 것들로 제한되지 않으며, 언급되지 않은 또 다른 기술적 효과들은 아래의 기재로부터 당업자에게 명확하게 이해될 수 있을 것이다.The technical effects of the present invention are not limited to those mentioned above, and other technical effects that are not mentioned will be clearly understood by those skilled in the art from the following description.
도 1a 및 도 1b는 본 발명의 일 실시예에 따른 태양전지의 사시도이다.1A and 1B are perspective views of a solar cell according to an embodiment of the present invention.
도 2는 본 발명의 일 실시예에 따른 태양전지용 광흡수층의 제조방법을 나타내는 흐름도이다.2 is a flowchart illustrating a method of manufacturing a light absorption layer for a solar cell according to an embodiment of the present invention.
도 3a 내지 도 3d는 본 발명의 일 실시예에 따른 태양전지용 광흡수층의 제조방법을 나타내는 공정도들이다.3A to 3D are process diagrams illustrating a method of manufacturing a light absorption layer for a solar cell according to an embodiment of the present invention.
도 4a 내지 도 4f는 본 발명의 일 실시예에 따라 제조된 광흡수층 표면의 AFM 이미지들이다.4A to 4F are AFM images of the surface of the light absorption layer manufactured according to one embodiment of the present invention.
도 5a 내지 도 5d는 본 발명의 일 실시예에 따른 태양전지의 제조방법을 나타내는 공정도들이다.5A to 5D are process diagrams illustrating a method of manufacturing a solar cell according to an embodiment of the present invention.
도 6은 본 발명의 일 실시예에 따른 태양전지의 에너지 밴드 다이어그램이다.6 is an energy band diagram of a solar cell according to an embodiment of the present invention.
도 7은 본 발명의 일 실시예에 따른 태양전지의 I-V 곡선을 나타내는 그래프이다.7 is a graph showing the I-V curve of the solar cell according to an embodiment of the present invention.
이하, 첨부한 도면들을 참조하여 본 발명의 바람직한 실시예들을 상세히 설명한다. 그러나, 본 발명은 여기서 설명되는 실시예들에 한정되지 않고 다른 형태로 구체화될 수 있으며, 본 발명의 사상 및 기술 범위에 포함되는 모든 균등물 내지 대체물을 포함하는 것으로 이해되어야 한다.Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms and should be understood to include all equivalents and substitutes included in the spirit and scope of the present invention.
본 명세서에서 층이 다른 층 또는 기판 "상"에 있다고 언급되는 경우에 그것은 다른 층 또는 기판 상에 직접 형성될 수 있거나, 그들 사이에 제3의 층이 개재될 수도 있다. 또한, 본 명세서에서 위쪽, 상(부), 상면 등의 방향적인 표현은 그 기준에 따라 아래쪽, 하(부), 하면 등의 의미로 이해될 수 있다. 즉, 공간적인 방향의 표현은 상대적인 방향으로 이해되어야 하며 절대적인 방향을 의미하는 것으로 한정 해석되어서는 안 된다.Where a layer is referred to herein as "on" another layer or substrate, it may be formed directly on the other layer or substrate, or a third layer may be interposed therebetween. In addition, in the present specification, the directional expression of the upper part, the upper part, and the upper part may be understood as meanings of the lower part, the lower part, the lower part, and the like according to the criteria. In other words, the expression of the spatial direction should be understood as a relative direction and should not be construed as limiting the absolute direction.
도면들에 있어서, 층 및 영역들의 두께는 명확성을 기하기 위하여 과장 또는 생략된 것일 수 있다. 명세서 전체에 걸쳐서 동일한 참조번호들은 동일한 구성요소들을 나타낸다.In the drawings, the thicknesses of layers and regions may be exaggerated or omitted for clarity. Like numbers refer to like elements throughout.
도 1a 및 도 1b는 본 발명의 일 실시예에 따른 태양전지의 사시도이다.1A and 1B are perspective views of a solar cell according to an embodiment of the present invention.
도 1a를 참조하면, 제1 전극(100)은 기판(미도시) 상에 위치할 수 있다. 상기 기판은 소자를 지지하기 위해 사용되는 것으로 필요에 따라 제거될 수 있다. 상기 기판은 투명 무기물 기판일 수 있다. 예컨대, 상기 기판은 유리, 석영(quartz), Al2O3 및 SiC 중에서 선택될 수 있다. 또한, 상기 기판은 투명 유기물 기판일 수 있다. 예컨대, 상기 기판은 PET(polyethylene terephthlate), PES(polyethersulfone), PS(polystyrene), PC(polycarbonate), PI(polyimide), PEN(polyethylene naphthalate) 및 PAR(polyarylate) 중에서 선택될 수 있다.Referring to FIG. 1A, the first electrode 100 may be positioned on a substrate (not shown). The substrate is used to support the device and can be removed as needed. The substrate may be a transparent inorganic substrate. For example, the substrate may be selected from glass, quartz, Al 2 O 3 and SiC. In addition, the substrate may be a transparent organic substrate. For example, the substrate may be selected from polyethylene terephthlate (PET), polyethersulfone (PES), polystyrene (PS), polycarbonate (PC), polyimide (PI), polyethylene naphthalate (PEN), and polyarylate (PAR).
상기 제1 전극(100)은 후술하는 광흡수층(300)에서 발생한 정공을 수집하는 애노드(anode)의 역할을 수행한다. 상기 제1 전극(100)은 낮은 저항을 가지는 도전성 물질이면서 광을 투과시키기 위해 투명성을 가지는 물질로 이루어지는 것이 바람직하다. The first electrode 100 serves as an anode for collecting holes generated in the light absorption layer 300 to be described later. The first electrode 100 may be made of a conductive material having a low resistance and having a transparency to transmit light.
예컨대, 상기 제1 전극(100)은 탄소나노튜브(CNT), 그래핀, ITO, 도핑된 ZnO(AZO: Al 도핑, GZO: Ga 도핑, IZO: In 도핑, IGZO: In 및 Ga 도핑, MZO: Mg 도핑), Al 또는 Ga가 도핑된 MgO, Sn이 도핑된 In2O3, F가 도핑된 SnO2 또는 Nb가 도핑된 TiO2로 이루어질 수 있다. For example, the first electrode 100 is carbon nanotube (CNT), graphene, ITO, doped ZnO (AZO: Al doping, GZO: Ga doping, IZO: In doping, IGZO: In and Ga doping, MZO: Mg doped), MgO doped with Al or Ga, In 2 O 3 doped with Sn, SnO 2 doped with F, or TiO 2 doped with Nb.
상기 광흡수층(300)은 조사된 광을 흡수하여 여기 상태의 전자-정공 쌍, 즉, 엑시톤(exiton)을 형성하는 역할을 수행한다. The light absorbing layer 300 absorbs the irradiated light and forms an electron-hole pair, that is, an exciton, in an excited state.
상기 광흡수층(300)은 하부에 박막층(310)이 위치하고, 상기 박막층(310)의 상부에 나노응집체(330)들이 배열되는 구조를 가진다. 따라서, 상기 광흡수층(300)은 상기 나노응집체(330)들로 인해 표면에 요철 구조를 형성한다. The light absorbing layer 300 has a structure in which the thin film layer 310 is disposed below and the nanoaggregates 330 are arranged on the thin film layer 310. Therefore, the light absorption layer 300 forms an uneven structure on the surface due to the nano-aggregates 330.
상기 요철 구조는 광흡수 물질을 잘 용해시키는 용매(양용매)와 잘 용해시키지 않는 용매(빈용매)의 두 용매에 용해시켜 나타나는 용해도 차이로 자발 형성될 수 있다. The uneven structure may be spontaneously formed by a difference in solubility resulting from dissolving in a solvent (good solvent) that dissolves light absorbing material well and a solvent (poor solvent) that does not dissolve well.
상기 광흡수층(300)의 하부에 위치하는 박막층(310)은 양용매에 고르게 용해된 광흡수 물질을 포함하고, 상부의 나노응집체(330)들은 광흡수 물질이 빈용매에서 응집(aggregation)을 일으켜 형성된다.The thin film layer 310 positioned below the light absorbing layer 300 includes a light absorbing material evenly dissolved in a good solvent, and the nano-aggregates 330 on the upper side cause the light absorbing material to aggregate in a poor solvent. Is formed.
상기 광흡수 물질은 광흡수 유기물 및 무기물 중에서 적어도 하나 선택될 수 있다. 상기 광흡수 유기물은 유기 반도체 물질 및 인광 물질 중에서 선택되는 적어도 하나일 수 있다. 또한, 상기 광흡수 무기물은 단일 구조 또는 코어-쉘의 이중 구조를 가지는 양자점을 포함하는 무기 반도체 물질일 수 있다. The light absorbing material may be selected from at least one of a light absorbing organic material and an inorganic material. The light absorbing organic material may be at least one selected from organic semiconductor materials and phosphorescent materials. In addition, the light absorbing inorganic material may be an inorganic semiconductor material including a quantum dot having a single structure or a dual structure of a core-shell.
예컨대, 상기 광흡수 유기물은 펜타센(Pentacene), PDCDT, PenPTC, ZnPC, CuPC, TiOPC, Coumarin 6, P3HT, P3KT, PT, PTCBI, ADIDI, PTCDA, PTCDI, Spiro-MeOTAD, NTDA, MePTC, HepPTC, F16CuPC, P3OT, MEH-PPV, MDMO-PPV, PFO, PFO-DMP, SubPc, N3 및 PBDTTT으로 구성되는 군, 및 Ir, Pt, Eu 또는 Tb 계열의 화합물 중에서 적어도 하나 선택될 수 있다.For example, the light absorbing organic material may be pentacene, PDCDT, PenPTC, ZnPC, CuPC, TiOPC, Coumarin 6, P3HT, P3KT, PT, PTCBI, ADIDI, PTCDA, PTCDI, Spiro-MeOTAD, NTDA, MePTC, HepPTC, At least one selected from the group consisting of F16CuPC, P3OT, MEH-PPV, MDMO-PPV, PFO, PFO-DMP, SubPc, N3, and PBDTTT, and compounds of the Ir, Pt, Eu, or Tb family.
또한, 상기 광흡수 무기물은 MgO, MgS, MgSe, MgTe, CaO, CaS, CaSe, CaTe, SrO, SrS, SrSe, SrTe, BaO, BaS, BaSe, BaTE, ZnO, Cu2O, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe, HgO, HgS, HgSe, HgTe, Al2S3, Al2Se3, Al2Te3, Ga2O3, Ga2S3, Ga2Se3, Ga2Te3, In2O3, In2S3, In2Se3, In2Te3, GeO2, SnO2, SnS, SnSe, SnTe, PbO, PbO2, PbS, PbSe, PbTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, BP, Si 및 Ge로 구성되는 군으로부터 적어도 하나 선택될 수 있으며, CdTe/CdSe, CdSe/ZnTe, CdSe/ZnS, InP/ZnSe, InP/ZnS, InP/ZnTe, CdSe/ZnSe, InP/GaAs, InGaAs/GaAs, PbTe/PbS, CuInS2/ZnS, Co/CdSe, Zn/ZnO, Ag/TiO2, Ag/SiO2, Au/Pb, Au/Pt 및 Ru/Pt으로 구성되는 군으로부터 적어도 하나 선택될 수 있다.In addition, the light absorption inorganic material is MgO, MgS, MgSe, MgTe, CaO, CaS, CaSe, CaTe, SrO, SrS, SrSe, SrTe, BaO, BaS, BaSe, BaTE, ZnO, Cu 2 O, ZnS, ZnSe, ZnTe , CdO, CdS, CdSe, CdTe, HgO, HgS, HgSe, HgTe, Al 2 S 3 , Al 2 Se 3 , Al 2 Te 3 , Ga 2 O 3 , Ga 2 S 3 , Ga 2 Se 3 , Ga 2 Te 3 , In 2 O 3 , In 2 S 3 , In 2 Se 3 , In 2 Te 3 , GeO 2 , SnO 2 , SnS, SnSe, SnTe, PbO, Pb O 2, PbS, PbSe, PbTe, AlN, AlP, At least one may be selected from the group consisting of AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, BP, Si, and Ge, and CdTe / CdSe, CdSe / ZnTe, CdSe / ZnS, InP / ZnSe, InP / ZnS, InP / ZnTe, CdSe / ZnSe, InP / GaAs, InGaAs / GaAs, PbTe / PbS, CuInS 2 / ZnS, Co / CdSe, Zn / ZnO, Ag / TiO 2 , Ag / SiO 2 , At least one may be selected from the group consisting of Au / Pb, Au / Pt, and Ru / Pt.
상기 나노응집체(330)는 무기 반도체 물질, 유기 반도체 물질과 인광 물질의 조합, 및 유기 반도체 물질과 무기 반도체 물질의 조합 중에서 선택되는 어느 하나일 수 있다. 이 때, 상기 유기 반도체 물질과 조합되는 인광 물질 또는 무기 반도체 물질은 나노입자 형태를 가질 수 있다. The nano-aggregate 330 may be any one selected from an inorganic semiconductor material, a combination of an organic semiconductor material and a phosphor material, and a combination of an organic semiconductor material and an inorganic semiconductor material. In this case, the phosphorescent material or the inorganic semiconductor material combined with the organic semiconductor material may have a nanoparticle form.
따라서, 상기 나노응집체(330)가 유기 반도체 물질과 인광 물질의 조합 또는 유기 반도체 물질과 무기 반도체 물질의 조합인 경우, 나노입자 형태의 인광 물질 또는 무기 반도체 물질이 우수한 광흡수율을 가지므로, 더 많은 수의 엑시톤이 생성되어, 광전류가 증가될 수 있다. Therefore, when the nano-aggregate 330 is a combination of an organic semiconductor material and a phosphor material or a combination of an organic semiconductor material and an inorganic semiconductor material, since the phosphor or inorganic semiconductor material in the form of nanoparticles has an excellent light absorption rate, A number of excitons can be produced to increase the photocurrent.
더욱이, 인광 물질을 사용하는 경우, 확산거리가 증대된 삼중항 엑시톤이 형성되기 때문에 더 많은 수의 엑시톤들을 계면에서 분리시킬 수 있다.Moreover, when using a phosphor, triplet excitons with increased diffusion distances can be formed, allowing a greater number of excitons to be separated at the interface.
상기 광흡수층(300)의 요철 구조는 엑시톤을 분리시킬 수 있는 계면의 면적을 증가시켜, 전하의 재결합 비율을 감소시킨다. 따라서, 광전류가 증가하여 광전 변환 효율이 개선될 수 있다.The uneven structure of the light absorption layer 300 increases the area of the interface capable of separating excitons, thereby reducing the recombination rate of the charge. Therefore, the photocurrent can be increased to improve the photoelectric conversion efficiency.
전자 수송층(400)은 상기 광흡수층(300) 상에 위치한다. 상기 전자 수송층(400)은 상기 광흡수층(300)과 전자 수송층(400)의 계면(interface)에서 분리된 전자와 정공 중 전자를 포착하여 제2 전극(600)으로 수송하는 기능을 수행한다. The electron transport layer 400 is located on the light absorbing layer 300. The electron transport layer 400 performs a function of capturing electrons in electrons and holes separated at an interface between the light absorption layer 300 and the electron transport layer 400 and transporting the electrons to the second electrode 600.
상기 전자 수송층(400)은 유기 물질 또는 무기 물질을 함유할 수 있다. 예컨대, 상기 전자 수송층(400)은 풀러렌(C60, C70, C80) 또는 풀러렌 유도체인 PCBM([6,6]-phenyl-C61 butyric acid methyl ester)(PCBM(C60), PCBM(C70), PCBM(C80))을 포함하는 유기 물질을 함유할 수 있다. 또한, 상기 전자 수송층(400)은 ZnO, TiO2, SnO2 또는 탄소나노튜브를 포함하는 무기 물질을 함유할 수 있다.The electron transport layer 400 may contain an organic material or an inorganic material. For example, the electron transport layer 400 is fullerene (C60, C70, C80) or a fullerene derivative PCBM ([6,6] -phenyl-C61 butyric acid methyl ester) (PCBM (C60), PCBM (C70), PCBM ( C80)). In addition, the electron transport layer 400 may contain an inorganic material including ZnO, TiO 2 , SnO 2 or carbon nanotubes.
제2 전극(600)은 상기 전자 수송층(400) 상에 위치한다. 상기 제2 전극(600)은 광흡수층(300)에서 발생한 전자를 수집하는 캐소드(cathode)의 역할을 수행한다. The second electrode 600 is located on the electron transport layer 400. The second electrode 600 serves as a cathode for collecting electrons generated in the light absorption layer 300.
상기 제2 전극(600)은 일함수가 작은 금속, 합금, 전기 전도성 화합물 및 이들의 혼합물을 함유할 수 있다. 예컨대, 상기 제2 전극(600)은 Al, Au, Cu, Pt, Ag, W, Ni, Zn, Ti, Zr, Hf, Cd, Pd 및 이들의 합금 중에서 선택되는 어느 하나를 함유할 수 있다. 또한, 상기 제2 전극(600)은 CuAlO2/Ag/CuAlO2, ITO/Ag/ITO, ZnO/Ag/ZnO, ZnS/Ag/ZnS, TiO2/Ag/TiO2, ITO/Au/ITO, WO3/Ag/WO3 및 MoO3/Ag/MoO3 중에서 선택되는 어느 하나를 함유할 수 있다. 또한, 상기 제2 전극(600)은 그래핀, 탄소나노튜브, 전도성 고분자 및 이들의 복합체 중에서 선택되는 어느 하나를 함유할 수 있다. 특히, 상기 제2 전극(600)을 투명한 유기 전극으로 형성한 경우, 상부에서도 수광이 가능할 수 있다.The second electrode 600 may contain a metal, an alloy, an electrically conductive compound, and a mixture thereof having a small work function. For example, the second electrode 600 may contain any one selected from Al, Au, Cu, Pt, Ag, W, Ni, Zn, Ti, Zr, Hf, Cd, Pd, and alloys thereof. In addition, the second electrode 600 may include CuAlO 2 / Ag / CuAlO 2 , ITO / Ag / ITO, ZnO / Ag / ZnO, ZnS / Ag / ZnS, TiO 2 / Ag / TiO 2 , ITO / Au / ITO, It may contain any one selected from WO 3 / Ag / WO 3 and MoO 3 / Ag / MoO 3 . In addition, the second electrode 600 may contain any one selected from graphene, carbon nanotubes, conductive polymers, and composites thereof. In particular, when the second electrode 600 is formed of a transparent organic electrode, light reception may be possible even from above.
도 1b를 참조하면, 도 1a의 구성에 정공 수송층(hole transport layer, HTL)(200)과 전자 주입층(Electron injection layer)(500)이 더 포함될 수 있다. 상기 정공 수송층(200)과 전자 주입층(500) 이외의 구성에 대한 설명은 도 1a과 같으므로, 생략하기로 한다. Referring to FIG. 1B, a hole transport layer (HTL) 200 and an electron injection layer 500 may be further included in the configuration of FIG. 1A. Since the description of the components other than the hole transport layer 200 and the electron injection layer 500 is the same as in FIG. 1A, it will be omitted.
상기 정공 수송층(200)은 제1 전극(100)과 광흡수층(300) 사이에 개재될 수 있다. 전자 주입층(500)은 전자 수송층(400)과 제2 전극(600) 사이에 개재될 수 있다. The hole transport layer 200 may be interposed between the first electrode 100 and the light absorption layer 300. The electron injection layer 500 may be interposed between the electron transport layer 400 and the second electrode 600.
상기 정공 수송층(200)은 제1 전극(100)과 광흡수층(300) 사이에 위치하여 상기 광흡수층(300)에서 발생한 정공을 제1 전극(100)으로 용이하게 수송되도록 하는 역할을 수행한다. The hole transport layer 200 is positioned between the first electrode 100 and the light absorbing layer 300 so as to easily transport holes generated in the light absorbing layer 300 to the first electrode 100.
상기 정공 수송층(200)은 정공 수송 능력 뿐 아니라 전자 차단 특성과 박막 형성 능력이 우수한 화합물로 이루어지는 것이 바람직하다. The hole transport layer 200 is preferably made of a compound having excellent hole blocking ability as well as electron blocking properties and thin film formation ability.
예컨대, 상기 정공 수송층(200)은 PEDOT(폴리(3,4-에틸렌디옥시티오펜)), PSS(폴리(스티렌설포네이트)), 폴리아닐린, 프탈로시아닌, 펜타센, 폴리디페닐, 아세틸렌 및 이들의 유도체 등의 적어도 하나의 전도성 고분자, 또는 NPB, TPD, Spiro-TPD, Spiro-NPB, DMFL-TPD, DMFL-NPB, DPFL-TPD, DPFL-NPB, Spiro-TAD, BPAPF, NPAPF, NPBAPF, Spiro-2NPB, PAPB, 2,2'-Spiro-DBP, Spiro-BPA, TAPC, Spiro-TTB 또는 HMTPD 등의 유기물을 함유할 수 있으나, 이에 한정되는 것은 아니다. 보다 바람직하게는 상기 정공 수송층(200)은 PEDOT:PSS(폴리(3,4-에틸렌디옥시티오펜):폴리(스티렌설포네이트)) 혼합물을 함유할 수 있다.For example, the hole transport layer 200 may include PEDOT (poly (3,4-ethylenedioxythiophene)), PSS (poly (styrenesulfonate)), polyaniline, phthalocyanine, pentacene, polydiphenyl, acetylene and derivatives thereof At least one conductive polymer such as NPB, TPD, Spiro-TPD, Spiro-NPB, DMFL-TPD, DMFL-NPB, DPFL-TPD, DPFL-NPB, Spiro-TAD, BPAPF, NPAPF, NPBAPF, Spiro-2NPB , PAPB, 2,2'-Spiro-DBP, Spiro-BPA, TAPC, Spiro-TTB or may contain organic substances such as HMTPD, but is not limited thereto. More preferably, the hole transport layer 200 may contain a mixture of PEDOT: PSS (poly (3,4-ethylenedioxythiophene): poly (styrenesulfonate)).
상기 전자 주입층(500)은 전자 수송층(400)과 제2 전극(600) 사이에 위치하여 전자 주입을 향상시키는 역할을 수행한다. 상기 전자 주입층(500)은 얇은 두께의 절연막일 수 있다.The electron injection layer 500 is positioned between the electron transport layer 400 and the second electrode 600 to improve electron injection. The electron injection layer 500 may be an insulating film having a thin thickness.
예컨대, 상기 전자 주입층(500)은 LiF, Liq, TPBi, PBD, BCP, Bphen, BAlq, Bpy-OXD, BP-OXD-Bpy, TAZ, NTAZ, NBphen, Bpy-FOXD, OXD-7l, 3TPYMB, 2-NPIP, PADN, HNBphen, POPy2, BP4mPy, TmPyPB 및 BTB 중에서 선택되는 어느 하나를 함유할 수 있다.For example, the electron injection layer 500 may include LiF, Liq, TPBi, PBD, BCP, Bphen, BAlq, Bpy-OXD, BP-OXD-Bpy, TAZ, NTAZ, NBphen, Bpy-FOXD, OXD-7l, 3TPYMB, It may contain any one selected from 2-NPIP, PADN, HNBphen, POPy2, BP4mPy, TmPyPB and BTB.
도 2는 본 발명의 일 실시예에 따른 태양전지의 광흡수층 제조방법을 나타내는 흐름도이다.2 is a flowchart illustrating a method of manufacturing a light absorption layer of a solar cell according to an embodiment of the present invention.
도 3a 내지 도 3d는 본 발명의 일 실시예에 따른 태양전지의 광흡수층 제조방법을 나타내는 공정도들이다.3A to 3D are process diagrams illustrating a method of manufacturing a light absorption layer of a solar cell according to an embodiment of the present invention.
도 2 및 도 3a를 참조하면, 광흡수 물질(310a), 양용매(340), 빈용매(350)의 혼합 용액을 준비한다(S100). 상기 광흡수 물질(310a)은 광흡수 유기물 및 광흡수 무기물 중에서 적어도 하나 선택될 수 있다.2 and 3A, a mixed solution of the light absorbing material 310a, the good solvent 340, and the poor solvent 350 is prepared (S100). The light absorbing material 310a may be selected from at least one of a light absorbing organic material and a light absorbing inorganic material.
상기 양용매(340)는 상기 광흡수 물질(310a)의 용해도가 우수한 용매를 의미할 수 있다. 따라서, 상기 양용매(340)는 광흡수 물질(310a)의 극성과 동일한 극성을 가지는 것이 바람직하다.The good solvent 340 may refer to a solvent having excellent solubility of the light absorbing material 310a. Therefore, the good solvent 340 preferably has the same polarity as that of the light absorbing material 310a.
일 예로, 상기 광흡수 물질(310a)로 유기물인 P3HT(poly(3-hexylthiophen)을 사용하는 경우, 상기 양용매(340)로는 클로로벤젠(chlorobenzene) 또는 디클로로벤젠(dichlorobenzene)을 사용할 수 있다.For example, when the organic material P3HT (poly (3-hexylthiophen)) is used as the light absorbing material 310a, chlorobenzene or dichlorobenzene may be used as the good solvent 340.
또한, 상기 빈용매(350)는 상기 광흡수 물질(310a)의 용해도가 떨어지는 용매를 의미할 수 있다. 따라서, 상기 빈용매(350)는 광흡수 물질(310a)의 극성과 상이한 극성을 가지는 것이 바람직하다. In addition, the poor solvent 350 may refer to a solvent having low solubility of the light absorbing material 310a. Therefore, the poor solvent 350 preferably has a polarity different from that of the light absorbing material 310a.
상기 빈용매(350)는 상기 양용매(340)에 대해 일정한 부피비로 첨가할 수 있으며, 이는 실험 조건에 따라 다르게 설정할 수 있다.The poor solvent 350 may be added in a constant volume ratio with respect to the good solvent 340, which may be set differently according to experimental conditions.
일 예로, 상기 광흡수 물질(310a)로 유기물인 P3HT(poly(3-hexylthiophen)을 사용하는 경우, 상기 빈용매(350)로는 PGMEA(propylene glycol mono-methyl ether acetate)를 사용할 수 있다.For example, when P3HT (poly (3-hexylthiophen)), which is an organic material, is used as the light absorbing material 310a, PGMEA (propylene glycol mono-methyl ether acetate) may be used as the poor solvent 350.
상기 혼합 용액은 나노입자(320) 형태를 가지는 광흡수 유기물 또는 광흡수 무기물을 포함할 수 있다. 예컨대, 상기 나노입자(320) 형태의 광흡수 유기물 또는 광흡수 무기물은 인광 물질 또는 무기 반도체 물질일 수 있다. 상기 무기 반도체 물질은 단일 구조 또는 코어-쉘의 이중 구조를 가지는 양자점일 수 있다. 이 경우, 나노입자(320) 형태의 인광 물질 또는 양자점은 우수한 광흡수율을 가지므로, 더 많은 수의 엑시톤이 생성되어 광전류를 증가시키는 이점이 있다. The mixed solution may include a light absorbing organic material or a light absorbing inorganic material having a form of nanoparticles 320. For example, the light absorbing organic material or the light absorbing inorganic material in the form of the nanoparticle 320 may be a phosphor or an inorganic semiconductor material. The inorganic semiconductor material may be a quantum dot having a single structure or a dual structure of a core-shell. In this case, the phosphor or quantum dot in the form of nanoparticles 320 has an excellent light absorption, there is an advantage that a greater number of excitons are generated to increase the photocurrent.
표 1
양용매(빈용매) 빈용매(양용매)
클로로벤젠, 디클로로벤젠, 클로로포름, 톨루엔, 헥산 등 PGMEA, 에틸렌 글리콜, 테트라에톡시실란, 디부틸 에테르, 디메틸포름아미드(DMF), 자일렌, 물, 메탄올, 에탄올, 2-프로판올 등
Table 1
Good solvent (poor solvent) Poor solvent (good solvent)
Chlorobenzene, dichlorobenzene, chloroform, toluene, hexane, etc. PGMEA, ethylene glycol, tetraethoxysilane, dibutyl ether, dimethylformamide (DMF), xylene, water, methanol, ethanol, 2-propanol, etc.
표1 과 같이, 다양한 종류의 광흡수 물질(310a)에 대해 양용매-빈용매를 다양하게 조합하여 사용할 수 있다.As shown in Table 1, a good solvent-poor solvent may be used in various combinations for various kinds of light absorbing materials 310a.
도 2 및 도 3b를 참조하면, 양용매(340), 광흡수 물질(310a), 빈용매(350) 및 광흡수 나노입자(320)가 포함된 혼합 용액을 교반하여 나노응집체(330)가 형성된 조성물을 수득한다(S200).2 and 3B, the nano-aggregate 330 is formed by stirring the mixed solution including the good solvent 340, the light absorbing material 310a, the poor solvent 350, and the light absorbing nanoparticle 320. Obtain a composition (S200).
상기 교반을 통해 양용매(340)에 용해되어 있던 광흡수 물질(310a)의 일부와 광흡수 나노입자(320)가 빈용매(350)로 이동하면서, 나노응집체(330)가 형성될 수 있다. A portion of the light absorbing material 310a and the light absorbing nanoparticles 320 that are dissolved in the good solvent 340 through the stirring may move to the poor solvent 350, and the nanoaggregate 330 may be formed.
상기 나노응집체(330)는 광흡수 물질(310a)을 상기 나노입자(320)가 둘러싸고 있는 형태를 가진다. 상기 나노응집체(330)의 크기는 용매의 농도, 교반 시간, 도포 속도 및 시간 등을 조절하여 제어할 수 있다.The nanoaggregate 330 has a shape in which the nanoparticle 320 surrounds the light absorbing material 310a. The size of the nano-aggregate 330 can be controlled by adjusting the concentration of the solvent, the stirring time, the coating speed and the time.
도 2 및 도 3c를 참조하면, 나노응집체(330)가 포함된 조성물을 전극 또는 유기 박막층 상에 도포한다(S300). 일 예로, 상기 전극은 제1 전극(100)일 수 있으며, 상기 유기 박막층은 정공 수송층(200)일 수 있다. 2 and 3C, the composition including the nano-aggregate 330 is coated on the electrode or the organic thin film layer (S300). For example, the electrode may be the first electrode 100, and the organic thin film layer may be the hole transport layer 200.
상기 도포는 스핀 코팅, 스프레이 코팅, 딥 코팅, 스크린 프린팅, 잉크젯 프린팅, 그라비아 프린팅, 오프셋 프린팅 등의 코팅 또는 프린팅 방법 등을 필요에 따라 적절히 선택하여 수행할 수 있다. The coating may be carried out by appropriately selecting a coating or printing method such as spin coating, spray coating, dip coating, screen printing, inkjet printing, gravure printing, offset printing, etc. as necessary.
도 2 및 도 3d를 참조하면, 상기 도포된 조성물을 열처리하여 광흡수층(300)을 형성한다. 상기 열처리는 10분 내지 30분 동안 20℃ 내지 80℃의 온도 범위에서 수행할 수 있다.2 and 3D, the coated composition is heat-treated to form a light absorption layer 300. The heat treatment may be carried out at a temperature range of 20 ℃ to 80 ℃ for 10 to 30 minutes.
상기의 도포 및 열처리를 통해 양용매(340)에 잔존하는 광흡수 물질(310)은 하부에 박막층(310)으로 형성될 수 있다. 또한, 상기 박막층(310) 상에 나노응집체(330)가 증착될 수 있다. 따라서, 상부에 배열된 나노응집체(330)들로 인해 상기 광흡수층(300)은 표면에 요철 구조를 가진다. The light absorbing material 310 remaining in the good solvent 340 through the coating and heat treatment may be formed as a thin film layer 310 at the bottom. In addition, the nano-aggregate 330 may be deposited on the thin film layer 310. Therefore, the light absorption layer 300 has a concave-convex structure on the surface due to the nano-aggregates 330 arranged thereon.
도 4a 내지 도 4f는 본 발명의 일 실시예에 따라 제조된 광흡수층 표면의 AFM 이미지들이다. 도 4a 및 도 4b는 광흡수 유기물인 P3HT(poly(3-hexylthiophen)를 광흡수 물질로 사용하고, 빈용매로 PGMEA(propylene glycol mono-methyl ether acetate)를 사용하여 형성된 나노응집체의 AFM 이미지들이다. 도 4c 및 도 4d는 광흡수 무기물인 ZnSe/InP/ZnS를 광흡수 물질로 사용하고, 빈용매로 PGMEA(propylene glycol mono-methyl ether acetate)를 사용하여 형성된 나노응집체의 AFM 이미지들이다. 도 4e 및 도 4f는 광흡수 유기물인 P3HT(poly(3-hexylthiophen)를 광흡수 물질로 사용하고, 무기 나노입자인 ZnSe를 첨가하고, 빈용매로 PGMEA(propylene glycol mono-methyl ether acetate)를 사용하여 형성된 나노응집체의 AFM 이미지들이다.4A to 4F are AFM images of the surface of the light absorption layer manufactured according to one embodiment of the present invention. 4A and 4B are AFM images of nano-aggregates formed using P3HT (poly (3-hexylthiophen)), which is a light absorbing organic material, as a light absorbing material and using PGMEA (propylene glycol mono-methyl ether acetate) as a poor solvent. 4C and 4D are AFM images of nano-aggregates formed using ZnSe / InP / ZnS, which are light absorbing inorganic materials, as light absorbing materials and using propylene glycol mono-methyl ether acetate (PGMEA) as a poor solvent. FIG. 4F shows nanoparticles formed using P3HT (poly (3-hexylthiophen), a light absorbing organic material, as a light absorbing material, ZnSe, an inorganic nanoparticle, and PGMEA (propylene glycol monomethyl ether acetate) as a poor solvent. AFM images of aggregates.
도 4a 내지 도 4f를 참조하면, 광흡수 물질의 종류와 나노입자 형태의 광흡수 물질의 유무에 따라 약 3nm 내지 25nm의 길이를 가지는 나노응집체들이 조밀하거나 소밀하게 배열되어 요철 구조를 형성함을 확인할 수 있다. 상기 나노응집체들의 크기는 용매의 농도, 교반 시간, 도포 속도 및 시간 등을 조절하여 제어할 수 있다.4A to 4F, it is confirmed that nanoaggregates having a length of about 3 nm to 25 nm are densely or densely arranged according to the type of light absorbing material and the presence or absence of light absorbing material in the form of nanoparticles to form an uneven structure. Can be. The size of the nano-aggregates can be controlled by adjusting the concentration of the solvent, the stirring time, the application rate and time.
도 5a 내지 도 5d는 본 발명의 일 실시예에 따른 태양전지의 제조방법을 나타내는 공정도들이다.5A to 5D are process diagrams illustrating a method of manufacturing a solar cell according to an embodiment of the present invention.
도 5a를 참조하면, 제1 전극(100)이 형성된 기판(미도시) 상에 정공 수송층(200)을 형성한다.Referring to FIG. 5A, a hole transport layer 200 is formed on a substrate (not shown) on which the first electrode 100 is formed.
상기 제1 전극(100)은 투명한 전도성 금속 산화물, 각종 탄소 재료로 이루어질 수 있다. 상기 제1 전극(100)은 열기상 증착, 전자빔 증착, RF 스퍼터링 또는 마그네트론 스퍼터링법 등을 이용하여 상기 기판 상에 형성할 수 있다. The first electrode 100 may be made of a transparent conductive metal oxide and various carbon materials. The first electrode 100 may be formed on the substrate by using thermal image deposition, electron beam deposition, RF sputtering or magnetron sputtering.
이후, 상기 제1 전극(100) 상에 정공 수송층(200)을 형성한다. 상기 정공 수송층(200)은 전도성 고분자 물질을 함유할 수 있다. 상기 정공 수송층(200)은 스핀 코팅, 스프레이 코팅, 딥핑, 스퍼터링, 진공증착법 등을 이용하여 형성할 수 있다. Thereafter, a hole transport layer 200 is formed on the first electrode 100. The hole transport layer 200 may contain a conductive polymer material. The hole transport layer 200 may be formed using spin coating, spray coating, dipping, sputtering, vacuum deposition, or the like.
도 5b를 참조하면, 정공 수송층(200) 상에 광흡수층(300)을 형성한다. 상기 광흡수층(300)은 하부에 위치하는 박막층(310)과, 그 상부에 배열된 나노응집체(330)로 이루어질 수 있다. Referring to FIG. 5B, the light absorption layer 300 is formed on the hole transport layer 200. The light absorption layer 300 may be formed of a thin film layer 310 disposed below and a nano-aggregate 330 arranged thereon.
상기 광흡수층(300)의 제조방법은 도 2 및 도 3a 내지 도 3d에서 설명한 것과 동일하므로, 자세한 설명을 생략하기로 한다.Since the method of manufacturing the light absorbing layer 300 is the same as described with reference to FIGS. 2 and 3A to 3D, detailed descriptions thereof will be omitted.
도 5c를 참조하면, 광흡수층(300) 상에 전자 수송층(400)을 형성한다. Referring to FIG. 5C, the electron transport layer 400 is formed on the light absorption layer 300.
상기 전자 수송층(400)은 유기 물질 또는 무기 물질을 포함할 수 있다. 상기 전자 수송층(400)은 용액 공정을 이용하여 형성할 수 있다. 예컨대, 상기 전자 수송층(400)은 진공증착, 스핀 코팅, 딥 코팅, 드롭 코팅, 스프레이 코팅, 잉크젯 프린팅 또는 스크린 프린팅 등을 이용하여 형성할 수 있다. 이 때, 사용되는 유기 물질 또는 무기 물질의 종류 및 특성 등을 고려하여 적절한 두께로 형성할 수 있다.The electron transport layer 400 may include an organic material or an inorganic material. The electron transport layer 400 may be formed using a solution process. For example, the electron transport layer 400 may be formed using vacuum deposition, spin coating, dip coating, drop coating, spray coating, inkjet printing or screen printing. At this time, it may be formed in an appropriate thickness in consideration of the type and characteristics of the organic material or inorganic material used.
도 5d를 참조하면, 전자 수송층(300) 상에 제2 전극(600)을 형성한다. 이 때, 전자의 원활한 주입을 위해 얇은 두께의 전자 주입층(500)을 더 형성할 수 있다.Referring to FIG. 5D, a second electrode 600 is formed on the electron transport layer 300. In this case, a thin thickness electron injection layer 500 may be further formed to smoothly inject electrons.
상기 전자 주입층(500)은 LiF, Liq 등과 같이 절연 특성을 가지는 얇은 박막으로 형성하는 것이 바람직하다. 상기 제2 전극(600)은 우수한 도전성을 가지는 금속 또는 합금 이외에도, 각종 탄소 재료, 전도성 고분자 물질을 함유하도록 형성할 수 있다. 특히, 상기 제2 전극(600)을 투명한 유기 전극으로 형성한 경우, 상부에서도 수광이 가능할 수 있다.The electron injection layer 500 is preferably formed of a thin thin film having an insulating property, such as LiF, Liq. The second electrode 600 may be formed to contain various carbon materials and conductive polymer materials, in addition to a metal or an alloy having excellent conductivity. In particular, when the second electrode 600 is formed of a transparent organic electrode, light reception may be possible even from above.
상기 전자 주입층(500)은 진공증착, 스핀 코팅, 딥 코팅, 드롭 코팅, 스프레이 코팅, 잉크젯 프린팅 또는 스크린 프린팅을 이용하여 형성할 수 있다. 한편, 상기 제2 전극(600)은 열기상 증착, 전자빔 증착, RF 스퍼터링 또는 마그네트론 스퍼터링법 등을 이용하여 형성할 수 있다. The electron injection layer 500 may be formed using vacuum deposition, spin coating, dip coating, drop coating, spray coating, inkjet printing or screen printing. On the other hand, the second electrode 600 may be formed using a thermal image deposition, electron beam deposition, RF sputtering or magnetron sputtering method.
이하, 본 발명의 이해를 돕기 위해 바람직한 실험예(example)를 제시한다. 다만, 하기의 실험예는 본 발명의 이해를 돕기 위한 것일 뿐, 본 발명이 하기의 실험예에 의해 한정되는 것은 아니다.Hereinafter, preferred examples are provided to aid the understanding of the present invention. However, the following experimental examples are only for helping understanding of the present invention, and the present invention is not limited to the following experimental examples.
실험예Experimental Example
(1) 유리 기판에 ITO 투명 전극을 스핀 코팅법으로 형성한 후, 초음파 세척하여 기판 표면의 불순물을 제거하였다. (1) An ITO transparent electrode was formed on the glass substrate by spin coating, and then ultrasonically washed to remove impurities from the surface of the substrate.
(2) PEDOT와 PSS의 혼합 용액을 제조한 후, 상기 ITO 투명 전극 상에 4500rpm으로 스핀 코팅하여 도포하고, 핫플레이트에서 30분 동안 열을 가해 용매를 증발시켜 PEDOT: PSS 정공 수송층을 형성하였다. (2) After preparing a mixed solution of PEDOT and PSS, it was applied by spin coating at 4500rpm on the ITO transparent electrode, heat was applied for 30 minutes on a hot plate to evaporate the solvent to form a PEDOT: PSS hole transport layer.
(3) 상기 PEDOT: PSS 정공 수송층 상에 광흡수층을 형성하였는 바, 그 형성과정은 하기와 같다. (3) The light absorption layer was formed on the PEDOT: PSS hole transport layer. The formation process is as follows.
클로로벤젠에 P3HT를 용해시켜 광흡수층 형성을 위한 조성물을 제조하였다(샘플 1). P3HT was dissolved in chlorobenzene to prepare a composition for forming a light absorption layer (sample 1).
또한, 클로로벤젠에 P3HT를 용해시킨 후 Ir(ppy)3(샘플 2) 또는 ZnSe(샘플 3)을 3%의 질량비로 첨가하였다. 이후, 클로로벤젠: PGMEA에 대하여 10: 1의 부피비가 되도록 첨가하고, 스핀바(spin bar)를 사용하여 약 10분 혼합한 후, 수분 동안 초음파처리를 실시하여 P3HT: Ir(ppy)3(샘플 2)와 P3HT: ZnSe(샘플 3)의 나노응집체가 형성된 조성물을 제조하였다.Furthermore, after dissolving P 3 HT in chlorobenzene, Ir (ppy) 3 (sample 2) or ZnSe (sample 3) was added at a mass ratio of 3%. Thereafter, chlorobenzene was added in a volume ratio of 10: 1 to PGMEA, and mixed for about 10 minutes using a spin bar, and then subjected to sonication for several minutes to give P3HT: Ir (ppy) 3 (sample). 2) and P3HT: A composition in which nano-aggregates of ZnSe (sample 3) were formed was prepared.
(4) 상기 샘플 1, 샘플 2 및 샘플 3의 조성물을 PEDOT: PSS 정공 수송층 상에 스핀 코팅하고, 열처리하여 평면(planar) 또는 요철 구조를 가지는 광흡수층을 형성하였다. (4) The compositions of Samples 1, 2 and 3 were spin-coated on a PEDOT: PSS hole transport layer and heat treated to form a light absorption layer having a planar or uneven structure.
(5) 진공 증착 장비를 이용하여 전자 수송층으로 풀러렌(C60) 박막을 증착한 후, 상기 풀러렌(C60) 박막 상에 LiF 박막층 및 Al 전극을 증착하였다.(5) After depositing a fullerene (C60) thin film with an electron transport layer using a vacuum deposition equipment, a LiF thin film layer and an Al electrode were deposited on the fullerene (C60) thin film.
(6) 최종적으로 ITO 전극과 Al 전극에 외부 회로를 연결하여 태양전지를 제조하였다.(6) Finally, an external circuit was connected to the ITO electrode and the Al electrode to manufacture a solar cell.
도 6은 본 발명의 일 실시예에 따른 태양전지의 에너지 밴드 다이어그램이다.6 is an energy band diagram of a solar cell according to an embodiment of the present invention.
도 6을 참조하면, 태양광은 광흡수층(300)에 흡수되며, 광흡수층(300)은 태양광으로부터 빛에너지를 흡수하여 엑시톤을 생성한다. 생성된 엑시톤은 확산 이동하며, 광흡수층(300)과 전자 수송층(400)의 접합 계면에서 전자와 정공으로 분리된다. 분리된 전자는 전자 수송층(400)의 에너지 준위를 거쳐 제2 전극(600)으로 이동하며, 분리된 정공은 정공 수송층(200)의 에너지 준위를 거쳐 제1 전극(100)으로 이동한다. 상기와 같이 제1 전극(100) 및 제2 전극(600)에 모인 전하들은 광전류를 형성한다.Referring to FIG. 6, sunlight is absorbed by the light absorbing layer 300, and the light absorbing layer 300 absorbs light energy from sunlight to generate excitons. The generated excitons move and diffuse, and are separated into electrons and holes at the bonding interface between the light absorption layer 300 and the electron transport layer 400. The separated electrons move to the second electrode 600 through the energy level of the electron transport layer 400, and the separated holes move to the first electrode 100 through the energy level of the hole transport layer 200. As described above, the charges collected in the first electrode 100 and the second electrode 600 form a photocurrent.
도 7은 본 발명의 일 실시예에 따른 태양전지의 I-V 곡선을 나타내는 그래프이다.7 is a graph showing the I-V curve of the solar cell according to an embodiment of the present invention.
표 2
샘플 Jsc(mAcm-2) Voc(V) FF η(%)
샘플 1 6.2 0.32 0.4 0.8
샘플 2 7.5 0.33 0.48 1.18
샘플 3 8.6 0.35 0.53 1.59
TABLE 2
Sample J sc (mAcm -2 ) V oc (V) FF η (%)
Sample 1 6.2 0.32 0.4 0.8
Sample 2 7.5 0.33 0.48 1.18
Sample 3 8.6 0.35 0.53 1.59
표 2 및 도 7을 참조하면, 광흡수층이 평면 구조로 형성된 샘플 1의 태양전지의 경우 단락회로전류(Jsc)가 6.2 mAcm-2의 값을 가지는 반면, 요철 구조로 형성된 샘플 2 및 샘플 3의 태양전지의 경우, 각각 7.5 mAcm-2 및 8.6 mAcm-2 의 값을 가짐을 확인할 수 있다. 즉, 표면이 요철 구조로 형성된 태양전지에서 단락회로전류가 증가한 것을 확인할 수 있다. 또한, 샘플 1의 태양전지는 광전 변환효율(η)이 0.8%에 그치는 반면, 요철 구조에서는 각각 1.18% 및 1.59%의 값을 가져, 월등히 증가한 것을 확인할 수 있다.Referring to Table 2 and FIG. 7, in the case of the solar cell of Sample 1 having the light absorption layer having a planar structure, the short circuit current (J sc ) has a value of 6.2 mAcm −2 , while Sample 2 and Sample 3 formed of the uneven structure In the case of the solar cell, it can be seen that the values of 7.5 mAcm -2 and 8.6 mAcm -2 , respectively. That is, it can be seen that the short-circuit current increased in the solar cell formed of the uneven structure surface. In addition, while the photovoltaic conversion efficiency (η) of the sample 1 was only 0.8%, the uneven structure had values of 1.18% and 1.59%, respectively, and it was confirmed that the solar cell increased significantly.
이상, 본 발명의 바람직한 실시예를 들어 상세하게 설명하였으나, 본 발명은 상기 실시예에 한정되지 않고, 본 발명의 기술적 사상 및 범위 내에서 당 분야에서 통상의 지식을 가진 자에 의하여 여러가지 변형 및 변경이 가능하다.As mentioned above, although the preferred embodiment of this invention was described in detail, this invention is not limited to the said embodiment, A various deformation | transformation and a change by a person with ordinary skill in the art within the technical idea and the scope of the present invention. This is possible.

Claims (18)

  1. 양용매, 빈용매 및 광흡수 물질이 포함된 혼합 용액을 준비하는 단계;Preparing a mixed solution containing a good solvent, a poor solvent, and a light absorbing material;
    상기 혼합 용액을 교반하여 나노응집체가 자발 형성된 조성물을 수득하는 단계;Stirring the mixed solution to obtain a composition in which nanoaggregates are spontaneously formed;
    상기 나노응집체가 포함된 조성물을 태양전지용 전극 또는 유기 박막층 상에 도포하는 단계; 및Applying the composition containing the nano-aggregate on a solar cell electrode or an organic thin film layer; And
    상기 도포된 조성물을 열처리하여 요철 구조를 가지는 광흡수층을 형성하는 단계를 포함하는 태양전지용 광흡수층의 제조방법.Heat-treating the applied composition to form a light absorption layer having a concave-convex structure.
  2. 제1항에 있어서,The method of claim 1,
    상기 광흡수 물질은 광흡수 유기물 및 광흡수 무기물 중에서 선택되는 적어도 하나인 태양전지용 광흡수층의 제조방법.The light absorbing material is at least one selected from a light absorbing organic material and a light absorbing inorganic material.
  3. 제2항에 있어서,The method of claim 2,
    상기 광흡수 유기물은 유기 반도체 물질 및 인광 물질 중에서 선택되는 적어도 하나인 태양전지용 광흡수층의 제조방법.The light absorbing organic material is at least one selected from an organic semiconductor material and a phosphorescent material.
  4. 제2항에 있어서,The method of claim 2,
    상기 광흡수 무기물은 무기 반도체 물질인 태양전지용 광흡수층의 제조방법.The light absorbing inorganic material is a method of manufacturing a light absorbing layer for solar cells which is an inorganic semiconductor material.
  5. 제1항에 있어서,The method of claim 1,
    상기 양용매 및 상기 빈용매 중 어느 하나는 클로로벤젠, 디클로로벤젠, 클로로포름, 톨루엔 및 헥산으로 구성되는 군으로부터 선택되고, 나머지 하나는 PGMEA, 에틸렌 글리콜, 테트라에톡시실란, 디부틸 에테르, 디메틸포름아미드, 자일렌, 물, 메탄올, 에탄올 및 프로판올로 구성되는 군으로부터 선택되는 태양전지용 광흡수층의 제조방법.One of the good solvent and the poor solvent is selected from the group consisting of chlorobenzene, dichlorobenzene, chloroform, toluene and hexane, and the other is PGMEA, ethylene glycol, tetraethoxysilane, dibutyl ether, dimethylformamide And xylene, water, methanol, ethanol and propanol.
  6. 제1항에 있어서,The method of claim 1,
    상기 나노응집체는 무기 반도체 물질, 유기 반도체 물질과 인광 물질의 조합 및 유기 반도체 물질과 무기 반도체 물질의 조합 중에서 선택되는 적어도 하나인 태양전지용 광흡수층의 제조방법. The nano-aggregate is at least one selected from an inorganic semiconductor material, a combination of an organic semiconductor material and a phosphor material, and a combination of an organic semiconductor material and an inorganic semiconductor material.
  7. 제1항에 있어서,The method of claim 1,
    상기 나노응집체가 포함된 조성물을 태양전지용 전극 또는 유기 박막층 상에 도포하는 단계는 스핀 코팅, 스프레이 코팅, 딥 코팅, 스크린 프린팅, 잉크젯 프린팅, 그라비아 프린팅 및 오프셋 프린팅 중 어느 하나를 통해 수행되는 태양전지용 광흡수층의 제조방법.Applying the composition containing the nano-aggregate on the solar cell electrode or the organic thin film layer is a solar cell light is carried out by any one of spin coating, spray coating, dip coating, screen printing, inkjet printing, gravure printing and offset printing Method for producing absorbent layer.
  8. 제1 전극;A first electrode;
    상기 제1 전극 상에 형성되며, 광흡수 물질을 포함하는 광흡수층;A light absorption layer formed on the first electrode and including a light absorption material;
    상기 광흡수층 상에 형성된 전자 수송층; 및An electron transport layer formed on the light absorption layer; And
    상기 전자 수송층 상에 형성된 제2 전극을 포함하고,A second electrode formed on the electron transport layer,
    상기 광흡수층은 하부 박막층의 상부에 수직방향으로 돌출 형성된 나노응집체들이 배열되어 요철을 형성하며, The light absorbing layer is a nano-aggregates protruding in the vertical direction on the top of the lower thin film layer is arranged to form irregularities,
    상기 전자 수송층은 상기 나노응집체들 사이의 공간을 채우며 상기 나노응집체들을 덮도록 형성되는 태양전지.The electron transport layer is formed to fill the space between the nano-aggregates and to cover the nano-aggregates.
  9. 제8항에 있어서,The method of claim 8,
    상기 제1 전극과 상기 광흡수층 사이에 개재되는 정공 수송층을 더 포함하는 태양전지.The solar cell further comprises a hole transport layer interposed between the first electrode and the light absorption layer.
  10. 제8항에 있어서,The method of claim 8,
    상기 전자 수송층과 상기 제2 전극 사이에 개재되는 전하 주입층을 더 포함하는 태양전지.The solar cell further comprises a charge injection layer interposed between the electron transport layer and the second electrode.
  11. 제8항에 있어서,The method of claim 8,
    상기 광흡수 물질은 광흡수 유기물 및 무기물 중에서 선택되는 적어도 어느 하나인 태양전지.The light absorbing material is at least one selected from light absorbing organic and inorganic materials.
  12. 제11항에 있어서,The method of claim 11,
    상기 광흡수 유기물은 유기 반도체 물질 및 인광 물질 중에서 선택되는 적어도 하나이고, 상기 광흡수 무기물은 무기 반도체 물질인 태양전지.The light absorbing organic material is at least one selected from an organic semiconductor material and a phosphorescent material, and the light absorbing inorganic material is an inorganic semiconductor material.
  13. 제8항에 있어서,The method of claim 8,
    상기 나노응집체는 무기 반도체 물질, 유기 반도체 물질과 인광 물질의 조합 및 유기 반도체 물질과 무기 반도체 물질의 조합 중에서 선택되는 적어도 하나인 태양전지. The nano-aggregate is at least one selected from an inorganic semiconductor material, a combination of an organic semiconductor material and a phosphor, and a combination of an organic semiconductor material and an inorganic semiconductor material.
  14. 기판 상에 제1 전극을 형성하는 단계;Forming a first electrode on the substrate;
    상기 제1 전극 상에, 표면에 요철을 가지는 광흡수층을 형성하는 단계;Forming a light absorption layer having irregularities on a surface of the first electrode;
    상기 광흡수층 상에 전자 수송층을 형성하는 단계; 및Forming an electron transport layer on the light absorption layer; And
    상기 전자 수송층 상에 제2 전극을 형성하는 단계를 포함하는 태양전지의 제조방법.Forming a second electrode on the electron transport layer manufacturing method of a solar cell.
  15. 제14항에 있어서,The method of claim 14,
    상기 기판 상에 제1 전극을 형성하는 단계와, 상기 제1 전극 상에 광흡수층을 형성하는 단계 사이에 정공 수송층을 형성하는 단계를 더 포함하는 태양전지의 제조방법.And forming a hole transport layer between the step of forming a first electrode on the substrate and the step of forming a light absorption layer on the first electrode.
  16. 제14항에 있어서,The method of claim 14,
    상기 광흡수층 상에 전자 수송층을 형성하는 단계와 상기 전자 수송층 상에 제2 전극을 형성하는 단계 사이에 전자 주입층을 형성하는 단계를 더 포함하는 태양전지의 제조방법.And forming an electron injection layer between forming an electron transporting layer on the light absorbing layer and forming a second electrode on the electron transporting layer.
  17. 제14항에 있어서,The method of claim 14,
    상기 제1 전극 상에, 표면에 요철을 가지는 광흡수층을 형성하는 단계는,Forming a light absorption layer having irregularities on the surface on the first electrode,
    양용매, 광흡수 물질, 빈용매가 포함된 혼합 용액을 준비하는 단계;Preparing a mixed solution containing a good solvent, a light absorbing material, and a poor solvent;
    상기 혼합 용액을 교반하여 나노응집체가 자발 형성된 조성물을 수득하는 단계;Stirring the mixed solution to obtain a composition in which nanoaggregates are spontaneously formed;
    상기 나노응집체가 포함된 조성물을 제1 전극 상에 도포하는 단계; 및Applying the composition including the nano-aggregate on a first electrode; And
    상기 도포된 조성물을 열처리하는 단계를 포함하는 태양전지의 제조방법.Method of manufacturing a solar cell comprising the heat treatment of the applied composition.
  18. 제17항에 있어서,The method of claim 17,
    상기 나노응집체가 포함된 조성물을 제1 전극 상에 도포하는 단계는 스핀 코팅, 스프레이 코팅, 딥 코팅, 스크린 프린팅, 잉크젯 프린팅, 그라비아 프린팅 및 오프셋 프린팅 중에서 선택되는 어느 하나를 통해 수행되는 태양전지의 제조방법.The coating of the composition containing the nano-aggregate on the first electrode may be performed by any one selected from among spin coating, spray coating, dip coating, screen printing, inkjet printing, gravure printing, and offset printing. Way.
PCT/KR2012/005783 2011-07-21 2012-07-19 Method for preparing light absorption layer for solar cell, solar cell including light absorption layer, and manufacturing method thereof WO2013012271A2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR10-2011-0072687 2011-07-21
KR1020110072687A KR101244112B1 (en) 2011-07-21 2011-07-21 Method of manufacturing the optical absorber layer for solar cell, Solar cell including the optical absorber layer and Method of manufacturing the same

Publications (2)

Publication Number Publication Date
WO2013012271A2 true WO2013012271A2 (en) 2013-01-24
WO2013012271A3 WO2013012271A3 (en) 2013-04-04

Family

ID=47558625

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/KR2012/005783 WO2013012271A2 (en) 2011-07-21 2012-07-19 Method for preparing light absorption layer for solar cell, solar cell including light absorption layer, and manufacturing method thereof

Country Status (2)

Country Link
KR (1) KR101244112B1 (en)
WO (1) WO2013012271A2 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104409572A (en) * 2014-11-24 2015-03-11 新奥光伏能源有限公司 Manufacturing method of heterojunction solar cell
WO2015065162A1 (en) * 2013-11-04 2015-05-07 주식회사 엘지화학 Conductive structure and preparation method therefor
WO2015076572A1 (en) * 2013-11-20 2015-05-28 주식회사 엘지화학 Conductive structure and manufacturing method therefor
KR20160115588A (en) * 2015-03-27 2016-10-06 주식회사 엘지화학 Display device and method for manufacturing the same
US11127912B2 (en) 2018-07-17 2021-09-21 Samsung Electronics Co., Ltd. Light emitting device and display device including the same
CN116190481A (en) * 2023-03-01 2023-05-30 中国科学院长春光学精密机械与物理研究所 Colored photovoltaic cell and preparation method thereof

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101478448B1 (en) 2013-07-01 2015-01-02 서울대학교산학협력단 Method of manufacturing absorber layer containing semiconductor nanoparticles and method of manufacturing semiconductor device containing the same absorber layer
JP6373124B2 (en) * 2014-08-21 2018-08-15 東京応化工業株式会社 Coating liquid, light absorption layer for solar cell and solar cell, and production method thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20100138930A (en) * 2008-03-25 2010-12-31 스미또모 가가꾸 가부시키가이샤 Composition and photo-electric converting element obtained using the same
KR20110003812A (en) * 2009-07-06 2011-01-13 광주과학기술원 Organic solar cell using morphology controller and method for fabricating the same
KR20110007906A (en) * 2009-07-17 2011-01-25 한국과학기술원 Inverted transparent organic solar cell and method for manufacturing thereof

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TW200937656A (en) * 2008-02-29 2009-09-01 Univ Nat Chiao Tung An organic active-layer solution for a polymer solar cell and a method for preparing the same
JP2009001575A (en) * 2008-06-23 2009-01-08 Ozotech:Kk Agent for external use containing ozone-dissolved glycerol solution such as cosmetic, quasi-drug or medicament (pharmaceutical)
JP2010016270A (en) * 2008-07-07 2010-01-21 Fujifilm Corp Wavelength sweep light source
KR100959760B1 (en) * 2008-12-18 2010-05-25 재단법인대구경북과학기술원 Photovoltaic cell and method of manufacturing the same
KR101658534B1 (en) * 2009-12-15 2016-09-23 엘지디스플레이 주식회사 Solar cell and method for fabricaitng the same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20100138930A (en) * 2008-03-25 2010-12-31 스미또모 가가꾸 가부시키가이샤 Composition and photo-electric converting element obtained using the same
KR20110003812A (en) * 2009-07-06 2011-01-13 광주과학기술원 Organic solar cell using morphology controller and method for fabricating the same
KR20110007906A (en) * 2009-07-17 2011-01-25 한국과학기술원 Inverted transparent organic solar cell and method for manufacturing thereof

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015065162A1 (en) * 2013-11-04 2015-05-07 주식회사 엘지화학 Conductive structure and preparation method therefor
KR20150051915A (en) * 2013-11-04 2015-05-13 주식회사 엘지화학 Conductive structure body and method for manufacturing the same
KR101648636B1 (en) 2013-11-04 2016-08-16 주식회사 엘지화학 Conductive structure body and method for manufacturing the same
WO2015076572A1 (en) * 2013-11-20 2015-05-28 주식회사 엘지화학 Conductive structure and manufacturing method therefor
US9983705B2 (en) 2013-11-20 2018-05-29 Lg Chem, Ltd. Conductive structure and manufacturing method therefor
CN104409572A (en) * 2014-11-24 2015-03-11 新奥光伏能源有限公司 Manufacturing method of heterojunction solar cell
CN104409572B (en) * 2014-11-24 2017-02-22 新奥光伏能源有限公司 Manufacturing method of heterojunction solar cell
KR20160115588A (en) * 2015-03-27 2016-10-06 주식회사 엘지화학 Display device and method for manufacturing the same
US11127912B2 (en) 2018-07-17 2021-09-21 Samsung Electronics Co., Ltd. Light emitting device and display device including the same
CN116190481A (en) * 2023-03-01 2023-05-30 中国科学院长春光学精密机械与物理研究所 Colored photovoltaic cell and preparation method thereof
CN116190481B (en) * 2023-03-01 2024-01-26 中国科学院长春光学精密机械与物理研究所 Colored photovoltaic cell and preparation method thereof

Also Published As

Publication number Publication date
KR20130011503A (en) 2013-01-30
WO2013012271A3 (en) 2013-04-04
KR101244112B1 (en) 2013-03-18

Similar Documents

Publication Publication Date Title
WO2013012271A2 (en) Method for preparing light absorption layer for solar cell, solar cell including light absorption layer, and manufacturing method thereof
JP5591860B2 (en) Organic semiconductor and solar cell using the same
WO2011090336A2 (en) Solar cell, the photoelectric conversion efficiency of which is improved by means of enhanced electric fields
KR101082910B1 (en) Organic Solar Cells with Fused Ring Compounds
WO2015167225A1 (en) Organic solar cell and manufacturing method therefor
WO2014200309A1 (en) Organic photovoltaic cell and method for manufacturing same
WO2011062457A2 (en) Organic-inorganic hybrid solar cell and manufacturing method thereof
WO2015167230A1 (en) Solar cell and manufacturing method therefor
WO2015163658A1 (en) Stacked organic solar cell
KR101097090B1 (en) Organic Solar Cells with triphenylene compounds
WO2019039907A2 (en) Organic electronic device and manufacturing method thereof
WO2010090123A1 (en) Organic photoelectric conversion element, solar cell using same, and optical sensor array
JP2011119676A (en) Organic photoelectric conversion element
JP5362017B2 (en) Organic thin film solar cell
KR20130137889A (en) Solar cell and method of manufacturing the same
KR101055117B1 (en) Method for fabricating solar cell including nanostructure
US20160268532A1 (en) Solar cell module and method for manufacturing the same
WO2011052567A1 (en) Organic photoelectric conversion element
KR20110098300A (en) Organic solar cells with biphenyl compounds
WO2016047216A1 (en) Photoelectric conversion element
WO2012165670A1 (en) Method for fabricating solar cell including nanostructure
KR101942008B1 (en) Bulk hetero-junction solar cell and manufacturing the same
JP2016167511A (en) Solar battery module and manufacturing method for the same
KR101923625B1 (en) Method for manufacturing organic solar cell and organic solar cell manufactured by the same
JP6034429B2 (en) Photoelectric conversion device and method for manufacturing photoelectric conversion device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12815450

Country of ref document: EP

Kind code of ref document: A2

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12815450

Country of ref document: EP

Kind code of ref document: A2