A kind of method utilizing copper-indium-gallium-selenium alloy sputtering target material to produce CIGS thin-film
Technical field
The invention belongs to field of solar utilizing equipment, utilize single four element CIGS target materials efficient particularly to one
The method producing CIGS thin-film.
Background technology
In Guo Qujishinian, the manufacturing industry scale of solar panel expands rapidly.2011, U.S.'s solar energy industry
Rate of increase is up to 109%, leading in technical field of new energies.Copper-indium-galliun-selenium film solar cell is at solar energy
Cell panel field quickly grows, and it is generally sequentially provided with molybdenum on the glass film plates of one layer of rigidity or the corrosion resistant plate of flexibility
Layer (1), p-type CIGS thin-film absorbed layer (2), cadmium sulfide cushion (3), intrinsic zinc oxide (4), aluminum
-zinc oxide Window layer (5) and surface contact layer (6), be shown in Fig. 1.According to the research report of Lux Research, 2011
Year CIGS thin-film solar market production capacity reaches 1.2GW, and will reach 2.3GW in 2015;Other solar energys
Battery research institution all predicts that the market share of copper-indium-galliun-selenium film solar cell will be risen to by 3% in 2010
6% in 2015, and 33% will be reached at the year two thousand twenty.This fully shows that copper-indium-galliun-selenium film solar cell technology will
The solaode market of the Fashion of Future, and there is huge business potential.As well-known too with other by USDOE
Yang Neng battery research institution is classified as the most promising thin film solar cell technologies, copper-indium-galliun-selenium film solar cell
Technology just by feat of its widely advantage attract increasing research worker and investor.Up to now, CIGS
The efficiency of thin-film solar cells has breached 20.3%.Meanwhile, increasing company, mechanism are just
It is being devoted to realize the commercialization of this technology.
But, the commercialization process of copper-indium-galliun-selenium film solar cell the most still lag behind monocrystaline silicon solar cell and
Other thin-film solar cells, such as cadmium telluride thin-film battery.Copper-indium-galliun-selenium film solar cell is caused to realize extensive
The biggest obstacle of volume production is the production cost that CIGS thin-film is high.To the year two thousand twenty, USDOE is to solar-electricity
The system installation cost target of pond plate is 0.5 dollar/watt, and this is still higher than monocrystaline silicon solar cell and other thin film sun
Can battery.
Existing, the production method of CIGS thin-film generally can be divided into antivacuum method and vacuum method.Antivacuum method bag
Include electrochemical plating embrane method, ink-jet printing process, FASST method and method of spin coating etc.;Efficiency on the low side is that non-vacuum method still needs to
The big problem solved.Vacuum method mainly includes that common vapour deposition method and the sputtering of two steps add selenizing method.
Vapour deposition method is all a kind of common deposition process in laboratory and business are applied altogether.Vapour deposition method uses multiple evaporations altogether
Source and three step process manufacture CIGS thin-film absorbed layer, can well control technological parameter and regulation thin film composition knot
Structure and band gap.At present the copper-indium-galliun-selenium film solar cell of peak efficiency is exactly to manufacture in this way, this efficiently
Rate is mainly attributed to effective classification of gallium, creates rear back surface field simultaneously, prevents reconfiguring of electronics and cavity, thus
Effectively raise energy conversion efficiency.But, the uniformity of vapour deposition method still faces some problems when large-scale production altogether;
Meanwhile, the most accurately controlling each evaporation source is also the big problem that associating vapour deposition method needs to solve.
Two step sputtering methods.This method is the technology producing CIGS thin-film absorbed layer forefront at present.It includes sputtering
With technical processs such as selenizings.The method with copper gallium or copper/gallium target and indium target as raw material, use cosputtering or
The method of sputtering is by alloy deposition to amorphous thin film continuously;The most again thin film is entered in the environment of Selenium hydride. or selenium
Row selenizing, ultimately forms p-type absorbed layer.At present, the Solar Frontier company of Japan produces by the method
The low cost copper-indium-galliun-selenium film solar cell production line of 900MW production capacity.Miasole and Nuvosun company is also
The production line of 80MW and 50MW it is manufactured that respectively by the method.Target as sputter method or has led copper and indium
The scale of mass production of gallium selenium thin-film solar cells, because the method suffers from showing in large-area uniformity and high deposition rate
The advantage write.But, the last selenization process of the method has certain environment hidden danger, because hydrogen selenide gas has toxicity;
The method needs high temperature simultaneously, which increases process costs.
The pluses and minuses of the production method of the production method of CIGS thin-film are shown in Table 1.
The production method contrast of the production method of table 1 CIGS thin-film
Vapour deposition method can make copper-indium-galliun-selenium film solar cell efficiency reach 20.3% altogether, and this not only gives the credit to be deposited with work
Skill, the most also has the factor of structure optimization;And sputter three step process method on the hierarchy of gallium, not only have important breakthrough,
Defining rear aluminum back surface field, the product of the method synthesis simultaneously has the border structure of bulky grain degree, and this characteristic is proved to
To improving efficiency important role.It addition, doctor Stanbery of Heliovolt thinks that CIGS thin-film solar is electric
Pond efficiency additionally depends on the interior absorbed layer between the p-type CIGS of copper-rich and the n-type CIGS of lean copper and links knot
Structure.This interior absorbed layer links model and will can be good at explaining at present a lot of about copper-indium-galliun-selenium film solar cell
A difficult problem, also has the indium n-type copper and indium to lacking copper including gallium to the facilitation of the p-type CIGS structure rich in copper
The facilitation of gallium selenium structure.
Copper-indium-galliun-selenium film solar cell is accelerating into market.Although solar energy giant Solyndra before meets with
Some setbacks, but nova Solar Frontier emerging and becoming the maximum of copper-indium-galliun-selenium film solar cell industry
Winner;Copper-indium-galliun-selenium film solar cell leads whole solar energy industry by the problem of simply time.But, current
CuInGaSe absorbed layer deposition technique has had become as the biggest obstacle in its commercialization process.The most whole industry is urgent
Needs search out a kind of effective ways to overcome this obstacle, simultaneously will be by the big rule of copper-indium-galliun-selenium film solar cell plate
Modulus is produced cost and is dropped to below 1 dollar/watt.
Summary of the invention
Goal of the invention: it is an object of the invention to provide the life of the CIGS thin-film that a kind of production cost is low, absorption efficiency is high
Product method.
Technical scheme: the invention provides a kind of side utilizing copper-indium-gallium-selenium alloy sputtering target material to produce CIGS thin-film
Method, comprises the following steps:
(1) at 300-400 DEG C, use 40W-300W power using copper-indium-gallium-selenium alloy as target in substrate
Ground floor thin film in sputtering, sputtering time is 5-40min, forms the first lean layers of copper;Due to temperature and power
Relatively low, therefore indium gallium selenium atom can sputter out, and copper atom cannot sputter out, and therefore first is lean
Layers of copper be mainly composed of gallium indium selenium and a small amount of copper;
(2) at 500-600 DEG C, the power using 60W-350W is lean first using copper-indium-gallium-selenium alloy as target
Sputtering second layer thin film in layers of copper, sputtering time is 20min-3h, forms copper-rich layer;Due to temperature and
Power is higher, and therefore CIGS atom all can sputter out, so that being mainly composed of of copper-rich layer
CIGS;
(3) at 500-600 DEG C, use 20W-200W power using copper-indium-gallium-selenium alloy as target at copper-rich layer
On sputter third layer thin film, sputtering time is 5-40min, formed the second lean layers of copper, obtain CIGS
Thin film;Owing to power is relatively low, therefore indium gallium selenium atom can sputter out, and copper atom cannot sputter
Come, therefore the first lean layers of copper be mainly composed of gallium indium selenium and a small amount of copper.
Wherein, in step (1), the horizontal cross sectional geometry that is shaped as of described substrate is circular round pie or horizontal cross-section shape
Shape is square cube shaped.
Wherein, in step (1), described substrate is soda-lime glass, rustless steel thin slice, aluminium foil or plastic sheet, described in mould
Tablet preferred polyimide plastics or poly terephthalic acid class plastics.
Wherein, in step (1), described substrate surface is provided with sodium fluoride layer, and the thickness of described sodium fluoride layer is 3-20nm;
Thus ensure that in CuInGaSe absorbed layer, sodium atom content is between 1% to 15%, make the size of crystal grain increase, Jin Erti
The efficiency of high solar battery.
Wherein, in step (1), the thickness of described substrate is 2-6mm.
Wherein, in step (1), in described copper-indium-gallium-selenium alloy, the atomic number of CIGS is than being (20-25): (10-19):
(6-12.5): (50-60).
It is wherein, in step (1), further comprising the steps of: to use method of evaporating or sputtering method will to plate molybdenum layer in substrate,
The thickness of described molybdenum layer is 200-1500nm, and the resistivity of described molybdenum layer is 0.2-5 ohmcm.
Wherein, in step (2), further comprising the steps of: to use chemistry basin sedimentation (CBD) by the second lean layers of copper
On plate cadmium sulfide transition zone, the thickness of described cadmium sulfide transition zone is 40-250nm, then under the conditions of 150-250 DEG C
Annealing 1-5min.
Beneficial effect: the production method of CIGS thin-film that the present invention provides will be deposited with altogether three step process method and antivacuum in
Portion absorbed layer connecting structure method combines, and can not only be obviously improved utilization rate of raw materials, low cost, and sputtering technology
During sedimentation rate fast, the most also will form gallium gradient-structure and the nanometer farmland p-n of optimization in CuInGaSe absorbed layer
Absorbed layer connecting structure IAJ in knot, the CIGS thin-film efficiency produced is high, area is big, the uniformity is high.
Specifically, the present invention has an advantage highlighted below relative to prior art:
1. efficiency is high
In order to obtain high efficiency product and reduce production cost, the present invention uses CIGS sputtering target material and three steps deposition
Technique, to obtain the thin film of the CIGS thin-film absorbent layer structure with uniqueness, thus improves battery efficiency.This
Bright most important innovative point be uniqueness CIGS thin-film absorbent layer structure: the hierarchy of gallium, large-sized granule
Absorbed layer connecting structure in the p-n on interface and nanometer farmland.The present invention by changing size of current, base reservoir temperature and will be spattered
Penetrate power to realize the deposition of high efficiency battery core layer, thus obtain the hierarchy of gallium, large-sized granular boundary with
And absorbed layer connecting structure in the p-n on nanometer farmland.Whole CIGS thin-film absorbed layer is made up of nanometer p-n structure, because of
This electronics and hole recombination form the probability of photon and diminish, and battery efficiency will be improved.Gallium hierarchy can produce
Rear back surface field, reduces electronics and hole recombination probability, is that common vapour deposition method can obtain high efficiency CIGS thin-film solar
The key factor of battery;The connecting structure (IAJ) of interior absorbed layer can also be formed simultaneously, so that electronics and hole weight
Group forms the probability of photon and diminishes, and makes CIGS thin-film efficiency get a promotion, and the unique texture of product makes CIGS thin
Film solar cell all has commercial competitiveness in efficiency and cost.
Owing to using CIGS four mischmetal target, the rich content of selenium in target, in whole step, that is plated is thin
Film is from the beginning to the end all in the atmosphere of selenizing.The CIGS thin-film prepared need not again through selenization process, it is to avoid
Selenium hydride. and the pollution of other toxic gas.Meanwhile, substantially reduce the production time, saved heating cost, thus
Reduce the manufacturing cost of final products.
2. low cost
The best method of the manufacture of solar cells cost reducing CIGS thin-film mainly will rely on three aspects: 1. improve former
The utilization rate of material;2. optimize production process and technique thus improve speed of production and productivity;3. optimize product structure and carry
The efficiency of high solar cell panel.The production method of the present invention will significantly improve production efficiency, simplify production technology, carry
High solar battery efficiency, will not form pressure to environmental conservation simultaneously, thus eventually reduce CIGS thin-film
The production cost of solaode.
3. the CIGS thin-film uniformity prepared is high
The present invention uses four mischmetal sputtering target materials to replace traditional copper gallium/copper/gallium and indium target, and four mischmetals spatter
Material of shooting at the target can be accurately controlled CuInGaSe absorbed layer structure, thus ensure that because sputtering copper and indium gallium prepared by method processed
Selenium thin film has more preferable uniformity while having large area, high deposition rate.
4. it is widely used
The present invention will reduce the production cost of copper-indium-galliun-selenium film solar cell, thus expands the application of solaode
Field, such as space exploration, rural area electrification and building field.The preparation method technology of the present invention by great business potential,
And bring lifting and Gospel for whole industry and environmental protection.
Accompanying drawing explanation
Fig. 1 is the structural representation of copper indium gallium selenium solar cell.
Fig. 2 is the flow chart that the present invention prepares CIGS thin-film.
Detailed description of the invention
According to following embodiment, the present invention be may be better understood.But, as it will be easily appreciated by one skilled in the art that reality
Execute concrete material proportion, process conditions and result thereof described by example and be merely to illustrate the present invention, and should also will not
Limit the present invention described in detail in claims.
Embodiment 1
Utilize the method that copper-indium-gallium-selenium alloy sputtering target material produces CIGS thin-film, copper in described copper-indium-gallium-selenium alloy
A diameter of 3 inches of indium gallium selenium, thickness be 1/4 inch, atomic number than for 25:17.5:7.5:50, including following step
Rapid:
(1) plate sodium fluoride layer with method of evaporating at soda-lime glass substrate surface, evaporation conditions be initial depression be 10-6
Torr, voltage 7KV, electric current 20mA, the thickness of described sodium fluoride layer is 3nm;
(2) using sputtering method to plate molybdenum layer by being coated with in the soda-lime glass substrate of sodium fluoride layer, evaporation conditions is initial true
Reciprocal of duty cycle is 10-6Torr, the argon being passed through 20SCCM make vacuum pressure reach 6mTorr, sputtering power 150W, spatter
Penetrating time 45min, the thickness of described molybdenum layer is 200nm, and the resistivity of described molybdenum layer is 5 ohmcms;
(3) at 300 DEG C, the power of 40W is used to be coated with fluorine at thickness as 2mm as target with copper-indium-gallium-selenium alloy
Changing and sputter ground floor thin film in the soda-lime glass substrate of sodium layer and molybdenum layer, sputtering time is 5min, forms the first lean copper
Layer;Described substrate be shaped as round pie, its horizontal cross sectional geometry is circular;
(4) at 500 DEG C, the power of 60W is used to sputter in the first lean layers of copper using copper-indium-gallium-selenium alloy as target
Second layer thin film, sputtering time is 3h, forms copper-rich layer;
(5) at 500 DEG C, the power of 20W is used to sputter the 3rd using copper-indium-gallium-selenium alloy on copper-rich layer as target
Layer film, sputtering time is 40min, forms the second lean layers of copper;
(6) use chemistry basin sedimentation will to plate cadmium sulfide transition zone in the second lean layers of copper, obtain the copper and indium gallium of overall lean copper
Selenium thin film, the thickness of described cadmium sulfide transition zone is 40nm, and concrete operations are: by distilled water and the 37.5ml of 240ml
The mixing of 28-30% ammonia after, sequentially add the cadmium sulfate of 0.015mol33ml, 1.5mol16.5ml sulfur urine mixed
Close, add the material that step (5) obtains, maintain water temperature at 55-80 DEG C, and be stirred continuously 5min to 1h, then use
Distilled water cleans for several times, dries up with nitrogen;Then anneal under the conditions of 250 DEG C 1min.
Embodiment 2
Utilize the method that copper-indium-gallium-selenium alloy sputtering target material produces CIGS thin-film, copper in described copper-indium-gallium-selenium alloy
A diameter of 3 inches of indium gallium selenium, thickness be 1/4 inch, atomic number than for 25:17.5:7.5:55, including following step
Rapid:
(1) plating sodium fluoride layer with method of evaporating at Thin Stainless Steel sheet substrate surface, evaporation conditions is initial depression
For 10-6Torr, voltage 7KV, electric current 20mA, the thickness of described sodium fluoride layer is 8nm;
(2) using sputtering method to plate molybdenum layer by being coated with in the soda-lime glass substrate of sodium fluoride layer, evaporation conditions is just
Beginning vacuum is 10-6Torr, be passed through the argon of 20SCCM make vacuum pressure reach 6mTorr, sputtering power 150W,
Sputtering time 45min, the thickness of described molybdenum layer is 600nm, and the resistivity of described molybdenum layer is 3.2 ohmcms;
(3) at 350 DEG C, use the power of 60W with copper-indium-gallium-selenium alloy as target in the thickness plating as 4mm
Having in the soda-lime glass substrate of sodium fluoride layer and molybdenum layer and sputter ground floor thin film, sputtering time is 15min, forms first
Lean layers of copper;Being shaped as of described substrate is cube shaped, and its horizontal cross sectional geometry is square;
(4) at 550 DEG C, the power of 200W is used to spatter in the first lean layers of copper using copper-indium-gallium-selenium alloy as target
Penetrating second layer thin film, sputtering time is 2h, forms copper-rich layer;
(5) at 550 DEG C, the power of 60W is used to sputter on copper-rich layer using copper-indium-gallium-selenium alloy as target
Third layer thin film, sputtering time is 30min, forms the second lean layers of copper;
(6) chemistry basin sedimentation is used will to plate cadmium sulfide transition zone, described cadmium sulfide transition zone in the second lean layers of copper
Thickness be 150nm, obtain the CIGS thin-film of overall lean copper;Concrete operations are: by the distilled water of 240ml with
After the 28-30% ammonia mixing of 37.5ml, sequentially add the cadmium sulfate of 0.015mol33ml, 1.5mol16.5ml
Sulfur urine mixing, maintain water temperature at 55-80 DEG C, the CIGS sample that step (5) prepares put in this solution,
And it is stirred continuously 5min to 1h, the sample plating cadmium sulfide is taken out, then cleans for several times with distilled water, blow with nitrogen
Dry, then anneal under the conditions of 150 DEG C 5min.
Embodiment 3
Utilize the method that copper-indium-gallium-selenium alloy sputtering target material produces CIGS thin-film, copper in described copper-indium-gallium-selenium alloy
A diameter of 3 inches of indium gallium selenium, thickness be 1/4 inch, atomic number than for 20:10:12.5:50, including following step
Rapid:
(1) plating sodium fluoride layer with method of evaporating at aluminium foil substrate surface, evaporation conditions is that initial vacuum is
10-6Torr, voltage 7KV, electric current 20mA, the thickness of described sodium fluoride layer is 14nm;
(2) using sputtering method to plate molybdenum layer by being coated with in the soda-lime glass substrate of sodium fluoride layer, evaporation conditions is
Initial vacuum degree is 10-6Torr, be passed through the argon of 20SCCM make vacuum pressure reach 6mTorr, sputtering power 150W,
Sputtering time 45min, the thickness of described molybdenum layer is 1000nm, and the resistivity of described molybdenum layer is 1.0 ohmcms;
(3) at 400 DEG C, use the power of 300W with copper-indium-gallium-selenium alloy as target at thickness as 5mm
Being coated with in the soda-lime glass substrate of sodium fluoride layer and molybdenum layer and sputter ground floor thin film, sputtering time is 30min, forms the
One lean layers of copper;Described substrate be shaped as round pie, its horizontal cross sectional geometry is circular;
(4) at 500 DEG C, the power of 350W is used to spatter in the first lean layers of copper using copper-indium-gallium-selenium alloy as target
Penetrating second layer thin film, sputtering time is 45min, forms copper-rich layer;
(5) at 550 DEG C, the power of 150W is used to sputter on copper-rich layer using copper-indium-gallium-selenium alloy as target
Third layer thin film, sputtering time is 20min, forms the second lean layers of copper;
(6) chemistry basin sedimentation is used will to plate cadmium sulfide transition zone, described cadmium sulfide transition zone in the second lean layers of copper
Thickness be 150nm, obtain the CIGS thin-film of overall lean copper;Concrete operations are: by the distilled water of 240ml with
After the 28-30% ammonia mixing of 37.5ml, sequentially add the cadmium sulfate of 0.015mol33ml, 1.5mol16.5ml
Sulfur urine mixing, maintain water temperature at 55-80 DEG C, the CIGS sample that step (5) prepares put in this solution,
And it is stirred continuously 5min to 1h, the sample plating cadmium sulfide is taken out, then cleans for several times with distilled water, blow with nitrogen
Dry, then anneal under the conditions of 150 DEG C 5min.
Embodiment 4
Utilize the method that copper-indium-gallium-selenium alloy sputtering target material produces CIGS thin-film, copper in described copper-indium-gallium-selenium alloy
A diameter of 3 inches of indium gallium selenium, thickness be 1/4 inch, atomic number than for 22.5:19:6:60, including following step
Rapid:
(1) plating sodium fluoride layer with method of evaporating at plastic base basal surface, evaporation conditions is that initial vacuum is
10-6Torr, voltage 7KV, electric current 20mA, the thickness of described sodium fluoride layer is 20nm;Described plastic sheet can be poly-
Acid imide plastics or poly terephthalic acid class plastics;
(2) using sputtering method to plate molybdenum layer by being coated with in the soda-lime glass substrate of sodium fluoride layer, evaporation conditions is
Initial vacuum degree is 10-6Torr, be passed through the argon of 20SCCM make vacuum pressure reach 6mTorr, sputtering power 150W,
Sputtering time 45min, the thickness of described molybdenum layer is 1500nm, and the resistivity of described molybdenum layer is 0.2 ohmcm;
(3) at 350 DEG C, use the power of 150W with copper-indium-gallium-selenium alloy as target at thickness as 6mm
Being coated with in the soda-lime glass substrate of sodium fluoride layer and molybdenum layer and sputter ground floor thin film, sputtering time is 40min, forms the
One lean layers of copper;Being shaped as of described substrate is cube shaped, and its horizontal cross sectional geometry is square;
(4) at 600 DEG C, the power of 250W is used to spatter in the first lean layers of copper using copper-indium-gallium-selenium alloy as target
Penetrating second layer thin film, sputtering time is 20min, forms copper-rich layer;
(5) at 600 DEG C, the power of 200W is used to sputter on copper-rich layer using copper-indium-gallium-selenium alloy as target
Third layer thin film, sputtering time is 5min, forms the second lean layers of copper;
(6) chemistry basin sedimentation is used will to plate cadmium sulfide transition zone, described cadmium sulfide transition zone in the second lean layers of copper
Thickness be 150nm, obtain the CIGS thin-film of overall lean copper;Concrete operations are: by the distilled water of 240ml with
After the 28-30% ammonia mixing of 37.5ml, sequentially add the cadmium sulfate of 0.015mol33ml, 1.5mol16.5ml
Sulfur urine mixing, maintain water temperature at 55-80 DEG C, the CIGS sample that step (5) prepares put in this solution,
And it is stirred continuously 5min to 1h, the sample plating cadmium sulfide is taken out, then cleans for several times with distilled water, blow with nitrogen
Dry, then anneal under the conditions of 150 DEG C 5min.
Embodiment 5
Utilize the method that copper-indium-gallium-selenium alloy sputtering target material produces CIGS thin-film, copper in described copper-indium-gallium-selenium alloy
A diameter of 3 inches of indium gallium selenium, thickness be 1/4 inch, atomic number than for 25:17.5:7.5:50, including following step
Rapid:
(1) at 450 DEG C, use the power of 50W with copper-indium-gallium-selenium alloy as target at the thickness sodium as 2mm
Sputtering ground floor thin film in lime glass substrate, sputtering time is 15min, forms the first lean layers of copper;
(2) at 550 DEG C, the power of 250W is used to spatter in the first lean layers of copper using copper-indium-gallium-selenium alloy as target
Penetrating second layer thin film, sputtering time is 45min, forms copper-rich layer;
(3) at 600 DEG C, the power of 50W is used to sputter on copper-rich layer using copper-indium-gallium-selenium alloy as target
Third layer thin film, sputtering time is 20min, forms the second lean layers of copper, obtains the CIGS thin-film of overall lean copper.
Embodiment 6
The CIGS thin-film utilizing embodiment 1 to 5 to prepare is used for copper-indium-galliun-selenium film solar cell, and measures too
Sun can battery efficiency.The Current-voltage data of solaode is at Oriel solar simulator and Keithley2400
Measure on current source instrument, run the efficiency that can directly obtain solaode software, often group from Labview I-V
Survey 3 times, the results are shown in Table 1.
Table 1 utilizes the prepared CIGS thin-film of embodiment 1 to 5 for the efficiency of copper-indium-galliun-selenium film solar cell