Classifications

• • 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
  • H01L31/0216—Coatings
  • H01L31/02161—Coatings for devices characterised by at least one potential jump barrier or surface barrier
  • H01L31/02167—Coatings for devices characterised by at least one potential jump barrier or surface barrier for solar 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
  • H01L31/04—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
  • H01L31/04—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
  • H01L31/043—Mechanically stacked 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
  • H01L31/04—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
  • H01L31/06—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 characterised by potential barriers
  • H01L31/068—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 characterised by potential barriers the potential barriers being only of the PN homojunction type, e.g. bulk silicon PN homojunction solar cells or thin film polycrystalline silicon PN homojunction solar 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
  • H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
• • 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
  • H01L31/1804—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof comprising only elements of Group IV of the Periodic Table
• • 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
  • Y02E10/547—Monocrystalline silicon 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

• This disclosure relates to photovoltaic devices.
• it relates to shingled solar cell modules.
• Shingled interconnection of solar cells although it was already introduced in 1956, is now drawing more attention within the industry market, as an emerging solar module fabrication technique. This concept can be used to maximise the device power conversion efficiency on a module level, as it increases the effective working area of a module while simultaneously reducing the shading and interconnection losses.
• Recent development of the shingled interconnection of solar cells involving a 72-cell solar module, reached an output of 442 W with an full area efficiency of 21.7%, using silicon hetero-junction (SHJ) bifacial solar cells.
• SHJ silicon hetero-junction
• the invention provides a method of providing a solar cell shingle, comprising the steps of providing a solar cell structure; forming at least one solar cell shingle using the solar cell structure, and passivating an edge portion of the solar cell shingle, at a location where the solar cell shingle is separated from another portion of the solar cell structure.
• the invention provides a method of providing a passivated solar cell shingle, including applying a passivating material to at least one edge of a solar cell shingle.
• forming the solar cell shingle from the solar cell structure can include scribing the solar cell structure, and mechanical separation of the solar cell structure at a location of the scribing.
• the scribing can be laser scribing.
• Forming the solar cell shingle from the solar cell structure can include cleaving the solar cell shingle from the solar cell structure.
• the step of applying a passivating material to the solar cell structure can be a final step in the manufacture of the solar cell shingle.
• the passivating material can be applied the solar cell shingle by deposition.
• the passivating material can be deposited onto the solar cell shingle by plasma-enhanced chemical vapor or by atomic layer deposition.
• the passivating material can be deposited in a layer of a thickness of
• the passivating material can provides surface passivation on silicon.
• the passivating material can be a metal oxide.
• the metal oxide can be AlOx, particularly AI2O3.
• the passivating material can be one of: amorphous silicon, or a material having a chemical formulation expressed as one of SiOx, SiNx, SiOxNy, AlOxNy, AINx, TiOx, SiCx.
• the method can include removal of silicon damage before the application of the passivating material.
• the present invention provides a solar cell shingle provided using any method as mentioned above.
• the present invention provides a shingled solar cell module including a plurality of the solar cell shingles mentioned above, the plurality of solar cell shingles being arranged in a stacked fashion, wherein each solar cell shingle overlaps a portion of an adjacent solar cell shingle.
• the passivating material can be applied before the plurality of solar cell shingles are stacked together. Alternatively, the passivating material can be applied after the plurality of solar cell shingles are stacked together.
• Figure l is a schematic drawing of a solar cell
• Figure 2 is a schematic drawing of four of the solar cell of Figure 1, scribed and cleaved into separate strips;
• Figure 3 is a schematic drawing of five solar cell strips being arranged together to form a shingled module
• FIG. 4 is a flow chart depicting a production process for providing a passivated emitter and rear cell (PERC) solar cell shingle, in accordance with one embodiment of the present invention
• Figure 5 is a flow chart depicting a production process for providing a PERC solar cell shingle, in accordance with another embodiment of the present invention.
• Figure 6-1 depicts the results of electrical simulation applied to a passivated solar cell shingle in accordance with present invention
• Figure 6-2 depicts the results of electrical simulation applied to a prior art solar cell shingle, which does not have edge passivation
• Figure 7 depicts simulation results showing the effect of shingle size on the efficiency of the shingled solar module, for both prior art solar cell shingles and solar cell shingles provided in accordance with the present invention.
• a shingled photovoltaic module instead of interconnecting the solar cells using ribbons, wires or strings, the interconnection of the solar cells is achieved by “overlapping” neighbouring solar cells.
• the arrangement of solar cell“shingles” in this way is similar to the laying of roof shingles. It maximises the area of the photovoltaic module that is covered with the solar cells, i.e. the packing density of the photovoltaic module.
• the solar cells are interconnected using, for example, soldering or an electrically conductive adhesive.
• Figure 1 and Figure 2 depict an example of preparing a solar cell for shingled interconnection.
• Figure 1 shows a solar cell 100 having electrodes including fingers (not shown) and busbars 102, 104, 106, 108, 110.
• the solar cell 100 for example of a length of about 156 to 160 millimetres (mm), is cut along the edges of the busbars 102, 104, 106, 108, 110.
• the arrows in Figure 1 indicate the separation lines.
• Figure 2 shows the four middle strips 122, 124, 126, 128 which result from the separation.
• Each strip 122, 124, 126, 128 includes a busbar 110, 1008, 106, 104.
• a plurality of the solar cell strips thus formed from the solar cell(s) are arranged together where each strip overlaps with a portion of an adjacent solar cell strip, i.e., in a shingled manner, as shown in Figure 3.
• the cell cutting process is performed using a technique known as laser scribe.
• Cells are firstly scribed by a laser and then separated mechanically. The separation is done by cleaving, sawing, or another technique.
• the laser scribing helps to reduce the loss of power due to increased recombination current at the strip edges, resulting from the cleaving damage.
• the current invention in one embodiment, involves the deposition of a
• passivating material on the separation (e.g., cleaved) edge or edges of the shingled cell strip, after the laser scribing and mechanical separation.
• An example of the passivating material is AlOx, such as AI2O3, for c-Si type solar cells.
• the passivating material is deposited as a layer having a thickness of about 5 nanometers (nm).
• a thermal process, or annealing, at about 400°C is applied to improve the passivation effect.
• Other materials e.g., metal oxides, with passivating qualities for the solar cell type of concern may be used.
• Potential materials include, but are not limited to, amorphous-Si, or a material having a chemical formulation expressed as one of SiOx, SiNx, SiOxNy, AINx, TiOx, SiCx.
• Factors to consider in the selection of passivating material include but are not limited to, the bandgap of the material (a higher bandgap reduces the likelihood of parasitic absorption), its level of surface passivation and in particular its level of chemical passivation, and how readily available the materials needed are. Given the material properties of the aforementioned materials and the selection requirements, another choice which the skilled person may consider is AlOxNy,
• FIG. 4 is a schematic flow chart of the manufacturing process 200 of a shingled Passivated Emitter and Rear Cell (PERC) in accordance one embodiment of the invention.
• Steps 210 to 232 in the flow chart are the fabrication steps 202 for making the PERC solar cell, prior to the scribing and cleaving step to cut the cell into shingles or strips.
• step 210 the saw damage resulted from wafer cutting is removed.
• concentrated sodium hydroxide typically at 30% weight/volume (w/v)
• a chemical bath maintained at 90 °C to remove (i.e.“etch”) the damaged regions from both surfaces of the wafer.
• the removal occurs at a rate of approximately 2 micrometers (pm) per minute.
• Surface texturing 212 is next performed on the etched wafer.
• the wafer is immersed in a chemical bath of sodium or potassium hydroxide, typically of about 2% w/v concentration.
• the chemical bath may be maintained at 80 to 90 °C to ensure a high pyramid nucleation rate. It can also have additives such as isopropanol at 5%(w/v).
• a cleaning step may be applied to the wafer, using 2% (w/v) each of hydrogen fluoride (HF) and hydrochloric acid (HC1), at room temperature.
• Steps 210 and 212 may be performed in one equipment in a production line.
• the emitter diffusion step 214 is typically, n-type layers are produced by phosphorus solid state diffusion, from a phosphorus glass (PSG) layer grown on the wafer surface, at temperatures generally in the range of 800 to 900 °C.
• PSG phosphorus glass
• the phosphorus glass is then removed in step 216. This is done by immersing wafers in a room-temperature solution of 1% to 5% (w/v) hydrofluoric acid (HF), and then rinsing in deionised water.
• HF hydrogen fluoride
• HC1 hydrochloric acid
• an edge isolation step 218 is performed. Typically, a cooled solution of hydrofluoric acid (HF) and nitric acid (HN03) is used. Again, steps 216 and 218 can be and generally are combined in one equipment in a production line. An anti -reflection coating is applied to the front side of the wafer in step 220 and to the rear side of the wafer in step 222.
• HF hydrofluoric acid
• HN03 nitric acid
• the front coating can be a SiNx material.
• the rear coating can be an AlOx/ SiNx stack.
• the coating steps utilises deposition, such as plasma enhanced chemical vapor deposition (PECVD) and ALD, to provide a thin and smooth layer of the coating material onto the existing layer(s).
• PECVD plasma enhanced chemical vapor deposition
• ALD atomic layer deposition
• the specific fabrication process 202 involved for forming the uncut PERC solar cell is not taken to be comprise essential limiting features of the present invention.
• the present invention can be applied to any types of solar cells suitable for forming shingled solar cell modules.
• a PERC solar cell After a PERC solar cell has been fabricated 202, it is separated (e.g., cut) into solar cell shingles or strips in step 204, and an ALD edge passivation step 206 is then applied.
• dielectric films are normally used to improve optics (antireflection coating), c-Si surface and bulk passivation.
• the layers should be present before metallisation and co-firing. Therefore, in the currently available solar cell production, dielectric depositions steps are only applied prior to the metallisation step.
• a dielectric deposition step 206 is further included as the final step in the fabrication process. The deposition steps in the manufacture provided in accordance with the present invention are coloured in grey.
• Figure 5 depicts a different embodiment of the fabrication process for the solar cell shingle. It is similar to that shown in Figure 4, except that after the shingle separation step 204, a silicon damage removal step 208 is performed (e.g. by chemical etching), prior to the ALD edge passivation 206, to remove the damaged to the silicon caused by the sawing or cleaving.
• the silicon damage removal step 208 further maximises the effectiveness of the technology, by reducing the roughness of the edge surface to which the ALD is applied.
• the silicon damage removal step 208 is performed in the same or a similar manner as the saw damage removal step 210.
• FIG. 6-1 shows the simulation results of a solar cell shingle in accordance with the present invention (i.e. with edge passivation).
• Figure 6-2 shows the simulation results of a prior art solar cell shingle.
• the light-coloured shapes 300, 302 in Figure 6-1 and Figure 6-2 correspond with the solar cell shingle, in plan view.
• the improvement in the efficiency of a shingled solar cell which can be achieved by the invention, will depend on the size of the solar cell“shingles” into which the solar cell is separated. Given a particular solar cell size, it is expected that the smaller the“shingles” are, the more cutting or cleaving would have occurred. More cuts or cleaved edges and hence possible leakage current locations would be present in the overall module. Thus, the application of edge passivation is expected to result in a larger efficiency improvement, in a smaller solar cell shingle, and thus in the solar cell module made from the smaller“shingles”.
• Figure 7 demonstrates the above described effect.
• the horizontal axis is the number of shingles produced from a solar cell of the same size.
• the numbers 2, 3, 4, and 5 along the axis would correspond with progressively smaller solar cell shingles, being 1/2, 1/3, 1/4, and 1/5 of the original size of a solar cell.
• the vertical axis shows the simulated efficiency of the solar cell shingle module comprising the number of shingles as indicated by the position along the horizontal axis.
• the efficiency of the overall shingled module increases, for both the prior art shingled module (square data points) and the shingled module according to the present invention (round data points).
• the shingled module according to the present invention achieves a higher efficiency for all simulated cases.
• a related advantage is that using the herein described invention, it is possible to produce solar cell shingles of a smaller size compared to existing solar cell shingles, without any or significant compromise in the conversion efficiency.
• the smaller shingle size allows for a potential reduction in the resistive loss in the module. It also allows a potential increase in the packing density of in the shingled solar cell module, which increases the power output of the module.
• the passivating material can be applied to the edges of the solar cell shingles, after the shingles are stacked together into the“shingled” module (see Figure 3).
• the stacking can thus simplify the edge passivating process.
• the passivating material can be applied prior to the stacking. Variations and modifications may be made to the parts previously described without departing from the spirit or ambit of the disclosure. Some possible variations of embodiments are described above. Furthermore, the application of the passivating material, after the metallization and cleaving steps in the production of the solar cell, is not limited to the edges of the solar cell shingles.

Landscapes

• Engineering & Computer Science (AREA)
• Computer Hardware Design (AREA)
• Power Engineering (AREA)
• Condensed Matter Physics & Semiconductors (AREA)
• Electromagnetism (AREA)
• General Physics & Mathematics (AREA)
• Physics & Mathematics (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Life Sciences & Earth Sciences (AREA)
• Sustainable Development (AREA)
• Manufacturing & Machinery (AREA)
• Sustainable Energy (AREA)
• Chemical & Material Sciences (AREA)
• Crystallography & Structural Chemistry (AREA)
• Photovoltaic Devices (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=73029269

Family Applications (1)

Country Status (2)

Cited By (1)

Citations (3)

• 2020
  • 2020-04-29 TW TW109114355A patent/TW202111965A/zh unknown
  • 2020-04-29 WO PCT/AU2020/050419 patent/WO2020220079A1/en active Application Filing

Patent Citations (3)

Also Published As

Similar Documents

Legal Events