CN105489663A - Method for improving performance of transparent conductive oxide ITiO thin film - Google Patents
Method for improving performance of transparent conductive oxide ITiO thin film Download PDFInfo
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- CN105489663A CN105489663A CN201510861183.0A CN201510861183A CN105489663A CN 105489663 A CN105489663 A CN 105489663A CN 201510861183 A CN201510861183 A CN 201510861183A CN 105489663 A CN105489663 A CN 105489663A
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- itio
- thin film
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- transparent oxide
- film
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- 238000000034 method Methods 0.000 title claims abstract description 53
- 239000010409 thin film Substances 0.000 title claims abstract description 17
- 238000000137 annealing Methods 0.000 claims abstract description 25
- 230000008021 deposition Effects 0.000 claims abstract description 21
- 239000000758 substrate Substances 0.000 claims abstract description 11
- 239000010408 film Substances 0.000 claims description 58
- 238000000151 deposition Methods 0.000 claims description 30
- 239000007789 gas Substances 0.000 claims description 23
- 238000004544 sputter deposition Methods 0.000 claims description 20
- 229910021417 amorphous silicon Inorganic materials 0.000 claims description 9
- 238000000427 thin-film deposition Methods 0.000 claims description 9
- 229910021419 crystalline silicon Inorganic materials 0.000 claims description 5
- 239000011521 glass Substances 0.000 claims description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 4
- 239000001257 hydrogen Substances 0.000 claims description 4
- 229910052739 hydrogen Inorganic materials 0.000 claims description 4
- 229910052760 oxygen Inorganic materials 0.000 claims description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 3
- 239000002985 plastic film Substances 0.000 claims description 3
- 229920006255 plastic film Polymers 0.000 claims description 3
- 238000012958 reprocessing Methods 0.000 claims description 3
- 229910052710 silicon Inorganic materials 0.000 claims description 3
- 239000010703 silicon Substances 0.000 claims description 3
- 238000005086 pumping Methods 0.000 abstract 3
- 239000007888 film coating Substances 0.000 abstract 1
- 238000009501 film coating Methods 0.000 abstract 1
- 238000007781 pre-processing Methods 0.000 abstract 1
- 238000002834 transmittance Methods 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 4
- 238000001755 magnetron sputter deposition Methods 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 3
- 238000004062 sedimentation Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000012827 research and development Methods 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 238000005137 deposition process Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010884 ion-beam technique Methods 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
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
- H01L31/0224—Electrodes
- H01L31/022408—Electrodes for devices characterised by at least one potential jump barrier or surface barrier
- H01L31/022425—Electrodes 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
- H01L31/02—Details
- H01L31/0224—Electrodes
- H01L31/022466—Electrodes made of transparent conductive layers, e.g. TCO, ITO layers
-
- 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
- H01L31/1884—Manufacture of transparent electrodes, e.g. TCO, ITO
-
- 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
-
- 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
Abstract
The invention belongs to the field of a solar cell, and specifically to a method for improving performance of a transparent conductive oxide ITiO thin film. The method comprises the following steps of a, preprocessing for the ITiO thin film before deposition, wherein background gas is pumped into deposition equipment, the background gas-pumping process is stopped after more than 20 min, and the deposition equipment is subjected to a vacuum-pumping operation; b, deposition of the ITiO thin film, wherein a film-coating substrate is put to the deposition equipment after the vacuum-pumping operation is implemented in the step a, and the ITiO thin film is deposited by adopting a spluttering method; and c, processing for the ITiO thin film after deposition, wherein the ITiO thin film obtained by deposition in the step b is subjected to annealing processing at a temperature of 150-300 DEG C to obtain the improved transparent conductive oxide ITiO thin film. The method is simple and can effectively improve the transmittance and the conductivity of the thin film.
Description
Technical field
The invention belongs to solar cell field, be specifically related to a kind of method improving transparent conductive oxide ITiO film performance used for solar batteries.
Background technology
Transparent conductive oxide film, due to its good electricity and optical property, is widely used in semiconductor and photovoltaic industry, as liquid crystal display, light-emitting diode, solar cell etc.In solar cell, comprise silicon-base thin-film battery, a ~ Si:H/c ~ Si heterojunction solar cell and CIGS hull cell etc., transparent conductive oxide (TCO) is as the front and back electrode of solar cell, need to possess the transmitance that within the scope of high electron mobility, low carrier concentration and battery response wave band, (300 ~ 1200nm) is high, thus improve the photoelectric conversion efficiency of solar cell.
The preparation method of common TCO thin film material has chemical vapour deposition technique, magnetron sputtering method, ion beam depositing etc.In these methods, magnetron sputtering is widely used in research and development and procedure for producing owing to having good controllability, high deposition rate and be easy to obtain large-area uniformity film.The optics of magnetron sputtering transparent conductive oxide ITiO and electric property strong depend on the technological parameters such as substrate temperature, sputtering pressure, gas flow and sputtering power in deposition process, wherein oxygen, hydrogen content are one of important technical parameters affecting ITiO film performance.
Therefore how obtained the ITiO film of high permeability and high conductivity by the optimization of process conditions, and the transparency electrode being applied to photovoltaic device becomes the problem that we are badly in need of solving simultaneously.
Summary of the invention
Technical problem to be solved by this invention is to provide a kind of preparation method improving transparent conductive oxide ITiO film transmission rate and electric conductivity.
A kind of method improving transparent oxide ITiO film performance of the present invention, comprises the following steps:
Preliminary treatment before a, ITiO thin film deposition: pass into background gas in depositing device, stops after being greater than 20min passing into background gas, is vacuumized by depositing device, make equipment vacuum degree be 8*10
-4~ 8*10
-2pa;
B, ITiO thin film deposition: coated basal plate is put into a step vacuumize after depositing device, adopt sputtering method deposition ITiO film, sputter gas is Ar and O
2;
Wherein, deposition pressure is 0.2 ~ 0.7Pa, and depositing temperature is 25 ~ 300 DEG C; Sputtering power density is 0.5 ~ 5W/cm
2;
C, ITiO thin film deposition reprocessing: b step is deposited the ITiO film obtained carry out annealing in process at 150 ~ 300 DEG C, obtain the transparent oxide ITiO film after improvement.
Further, as preferred technical scheme, a kind of method improving transparent oxide ITiO film performance described above, wherein utilizing vacuum pump to be evacuated to its vacuum degree to depositing device in a step is 7 × 10
-3pa.
A kind of method improving transparent oxide ITiO film performance described above, wherein background gas described in a step is at least one in air, compressed air, steam or hydrogen.
A kind of method improving transparent oxide ITiO film performance described above, wherein in b step, coated basal plate is the one in substrate of glass, plastic film substrates, silicon-based thin film solar cell, a-Si:H/c-Si heterojunction solar cell, CIGS thin film solar cell.
A kind of method improving transparent oxide ITiO film performance described above, wherein in b step, sputtering source is the one in direct current, intermediate frequency or radio frequency.
A kind of method improving transparent oxide ITiO film performance described above, wherein in b step sputter gas according to volume ratio, Ar:O
2=250:1 ~ 25:1.
Further, as preferred technical scheme, a kind of method improving transparent oxide ITiO film performance described above, wherein in b step sputter gas preferably according to volume ratio, Ar:O
2=25:1.
A kind of method improving transparent oxide ITiO film performance described above, wherein in step c, annealing in process is air annealing, vacuum annealing, N
2annealing, the annealing of Ar gas or H
2one in annealing.
A kind of method improving transparent oxide ITiO film performance of the present invention, the method passed into a certain amount of background gas before sputtering transparent conductive oxide ITiO film, to improve optics and the electric property of transparent conductive oxide ITiO film, the inventive method is simple, effectively can improve transmitance and the conductance of film.
Accompanying drawing explanation
Fig. 1 is the ITiO film transmission rate curve after embodiment 1 processes with comparative example 1; (wherein, ITiO is the process of comparative example 1 before optimizing, and ITiO is the process of embodiment 1 after optimizing)
Fig. 2 is the front and back electrode of ITiO conducting film for a-Si:H/c-Si hetero-junction solar cell, battery structure schematic diagram; (wherein, 1-be Ag electrode; 21-be TCO; 22-be a-Si:Hn
+layer; 23-be a-Si:Hi layer; 24-be p-type or N-shaped monocrystalline silicon; 25-for being a-Si:Hi layer; 26-be a-Si:Hp
+layer; 27-be TCO.)
Fig. 3 HIT battery EQE curve comparison.
Embodiment
A kind of method improving transparent oxide ITiO film performance of the present invention, comprises the following steps:
Preliminary treatment before a, ITiO thin film deposition: pass into background gas in depositing device, stops after being greater than 20min passing into background gas, is vacuumized by depositing device, make equipment vacuum degree be 8*10
-4~ 8*10
-2pa;
B, ITiO thin film deposition: coated basal plate is put into a step vacuumize after depositing device, adopt sputtering method deposition ITiO film, sputter gas is Ar and O
2; Wherein, deposition pressure is 0.2 ~ 0.7Pa, and depositing temperature is 25 ~ 300 DEG C; Sputtering power density is 0.5 ~ 5W/cm
2;
C, ITiO thin film deposition reprocessing: b step is deposited the ITiO film obtained carry out annealing in process at 150 ~ 300 DEG C, obtain the transparent oxide ITiO film after improvement.
Magnetron sputtering is widely used in research and development and procedure for producing owing to having good controllability, high deposition rate and be easy to obtain large-area uniformity film.This point is mentioned inside technical background.Further, as preferred technical scheme, a kind of method improving transparent oxide ITiO film performance described above, wherein utilizing vacuum pump to be evacuated to its vacuum degree to depositing device in a step is 7 × 10
-3pa.
A kind of method improving transparent oxide ITiO film performance described above, wherein background gas described in a step is at least one in air, compressed air, steam or hydrogen.
A kind of method improving transparent oxide ITiO film performance described above, wherein in b step, coated basal plate is the one in substrate of glass, plastic film substrates, silicon-based thin film solar cell, a-Si:H/c-Si heterojunction solar cell, CIGS thin film solar cell.
A kind of method improving transparent oxide ITiO film performance described above, wherein in b step, sputtering source is the one in direct current, intermediate frequency or radio frequency.
A kind of method improving transparent oxide ITiO film performance described above, wherein in b step sputter gas according to volume ratio, Ar:O
2=250:1 ~ 25:1.
Further, as preferred technical scheme, a kind of method improving transparent oxide ITiO film performance described above, wherein in b step sputter gas preferably according to volume ratio, Ar:O
2=25:1.
A kind of method improving transparent oxide ITiO film performance described above, wherein in step c, annealing in process is air annealing, vacuum annealing, N
2annealing, the annealing of Ar gas or H
2one in annealing.
Below in conjunction with embodiment, the specific embodiment of the present invention is further described, does not therefore limit the present invention among described scope of embodiments.
Embodiment 1
Before sputtering sedimentation transparent conductive oxide ITiO film, in sputtering cavity, drop into a certain amount of air, this process lasts half an hour.Then stop passing into of air, open vacuum pump, base vacuum is evacuated to 7 × 10
-3pa, puts into ultra-clear glasses substrate, starts to deposit ITiO conducting film.The sputtering power that experiment adopts is 1.17W/cm
2, DC power supply, deposition pressure is 0.65Pa, according to volume ratio Ar/O
2=25:1, the film thickness of room temperature deposition is 100nm, controls at about 40 Ω/ through 190 DEG C of vacuum annealing rear film sheet resistances, average through being 90.9% within the scope of 400 ~ 1200nm.
Comparative example 1
Before sputtering sedimentation transparent conductive oxide ITiO film, directly open vacuum pump, base vacuum is evacuated to 7 × 10
- 3pa, puts into glass substrate, starts to deposit ITiO conducting film.The sputtering power that experiment adopts is 1.17W/cm
2, DC power supply, deposition pressure is 0.65Pa, according to volume ratio Ar/O
2=25:1, the film thickness of room temperature deposition is 100nm, and after 190 DEG C of vacuum annealings, ITiO sheet resistance is about 70 Ω/, average through being 86.7% within the scope of 400 ~ 1200nm.Before and after the optimization of ITiO film, transmitance comparative result is shown in shown in accompanying drawing 1.
Embodiment 2
Before sputtering sedimentation transparent conductive oxide ITiO film, in sputtering cavity, drop into a certain amount of air, this process lasts half an hour.Then stop passing into of air, open vacuum pump, base vacuum is evacuated to 8 × 10
-4pa, puts into a-Si:H/c-Si heterojunction solar cell substrate, starts to deposit ITiO conducting film.The sputtering power that experiment adopts is 5W/cm
2, DC power supply, deposition pressure is 0.7Pa, according to volume ratio Ar/O
2=25:1, the film thickness of room temperature deposition is 100nm, through 150 DEG C of N
2annealing in process, as shown in Figure 2, its QE increases 1.9mA/cm to battery structure
2; As shown in Figure 3, battery efficiency rising 1.3% (absolute value).
Claims (8)
1. improve a method for transparent oxide ITiO film performance, it is characterized in that: comprise the following steps:
Preliminary treatment before a, ITiO thin film deposition: pass into background gas in depositing device, stops after being greater than 20min passing into background gas, is vacuumized by depositing device, make equipment vacuum degree be 8*10
-4~ 8*10
-2pa;
B, ITiO thin film deposition: coated basal plate is put into a step vacuumize after depositing device, adopt sputtering method deposition ITiO film, sputter gas is Ar and O
2;
Wherein, deposition pressure is 0.2 ~ 0.7Pa, and depositing temperature is 25 ~ 300 DEG C; Sputtering power density is 0.5 ~ 5W/cm
2;
C, ITiO thin film deposition reprocessing: b step is deposited the ITiO film obtained carry out annealing in process at 150 ~ 300 DEG C, obtain the transparent oxide ITiO film after improvement.
2. a kind of method improving transparent oxide ITiO film performance according to claim 1, is characterized in that: utilizing vacuum pump to be evacuated to its vacuum degree to depositing device in a step is 7 × 10
-3pa.
3. a kind of method improving transparent oxide ITiO film performance according to claim 1, is characterized in that: background gas described in a step is at least one in air, compressed air, steam or hydrogen.
4. a kind of method improving transparent oxide ITiO film performance according to claim 1, is characterized in that: in b step, coated basal plate is the one in substrate of glass, plastic film substrates, silicon-based thin film solar cell, a-Si:H/c-Si heterojunction solar cell, CIGS thin film solar cell.
5. a kind of method improving transparent oxide ITiO film performance according to claim 1, is characterized in that: in b step, sputtering source is the one in direct current, intermediate frequency or radio frequency.
6. a kind of method improving transparent oxide ITiO film performance according to claim 1, is characterized in that: in b step, sputter gas is according to volume ratio, Ar:O
2=250:1 ~ 25:1.
7. a kind of method improving transparent oxide ITiO film performance according to claim 6, is characterized in that: in b step, sputter gas is according to volume ratio, Ar:O
2=25:1.
8. a kind of method improving transparent oxide ITiO film performance according to claim 1, is characterized in that: in step c, annealing in process is air annealing, vacuum annealing, N
2annealing, the annealing of Ar gas or H
2one in annealing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510861183.0A CN105489663A (en) | 2015-12-01 | 2015-12-01 | Method for improving performance of transparent conductive oxide ITiO thin film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510861183.0A CN105489663A (en) | 2015-12-01 | 2015-12-01 | Method for improving performance of transparent conductive oxide ITiO thin film |
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| Publication Number | Publication Date |
|---|---|
| CN105489663A true CN105489663A (en) | 2016-04-13 |
Family
ID=55676526
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|---|---|---|---|
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019223261A1 (en) * | 2018-05-25 | 2019-11-28 | 中智(泰兴)电力科技有限公司 | Preparation method for transparent conductive oxide film of crystalline silicon heterojunction solar cell |
-
2015
- 2015-12-01 CN CN201510861183.0A patent/CN105489663A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019223261A1 (en) * | 2018-05-25 | 2019-11-28 | 中智(泰兴)电力科技有限公司 | Preparation method for transparent conductive oxide film of crystalline silicon heterojunction solar cell |
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Application publication date: 20160413 |
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