CN105355723B - Preparation method of silicon dioxide passivation film of crystalline silicon solar cell - Google Patents
Preparation method of silicon dioxide passivation film of crystalline silicon solar cell Download PDFInfo
- Publication number
- CN105355723B CN105355723B CN201510923285.0A CN201510923285A CN105355723B CN 105355723 B CN105355723 B CN 105355723B CN 201510923285 A CN201510923285 A CN 201510923285A CN 105355723 B CN105355723 B CN 105355723B
- Authority
- CN
- China
- Prior art keywords
- silicon
- silicon nitride
- silicon wafer
- nitride film
- battery
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Fee Related
Links
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims abstract description 52
- 238000002161 passivation Methods 0.000 title claims abstract description 31
- 239000000377 silicon dioxide Substances 0.000 title claims abstract description 31
- 235000012239 silicon dioxide Nutrition 0.000 title claims abstract description 20
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 229910021419 crystalline silicon Inorganic materials 0.000 title claims abstract description 15
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 68
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 68
- 239000010703 silicon Substances 0.000 claims abstract description 68
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 63
- 230000003647 oxidation Effects 0.000 claims abstract description 60
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims abstract description 60
- 229910052581 Si3N4 Inorganic materials 0.000 claims abstract description 59
- 238000000034 method Methods 0.000 claims abstract description 35
- 238000000151 deposition Methods 0.000 claims abstract description 17
- 238000004140 cleaning Methods 0.000 claims abstract description 11
- 239000011521 glass Substances 0.000 claims abstract description 7
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 19
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 13
- 229910017604 nitric acid Inorganic materials 0.000 claims description 13
- 238000004519 manufacturing process Methods 0.000 claims description 12
- 238000001035 drying Methods 0.000 claims description 8
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 7
- 239000011259 mixed solution Substances 0.000 claims description 4
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims 1
- 229910001873 dinitrogen Inorganic materials 0.000 claims 1
- 229910001882 dioxygen Inorganic materials 0.000 claims 1
- 238000002156 mixing Methods 0.000 claims 1
- 230000008569 process Effects 0.000 abstract description 20
- 229910021420 polycrystalline silicon Inorganic materials 0.000 abstract description 12
- 230000000694 effects Effects 0.000 abstract description 11
- 238000013329 compounding Methods 0.000 abstract description 3
- 238000005260 corrosion Methods 0.000 abstract description 2
- 230000007797 corrosion Effects 0.000 abstract description 2
- 230000002035 prolonged effect Effects 0.000 abstract description 2
- 210000004027 cell Anatomy 0.000 description 26
- 229910004205 SiNX Inorganic materials 0.000 description 14
- 229910052681 coesite Inorganic materials 0.000 description 10
- 229910052906 cristobalite Inorganic materials 0.000 description 10
- 229910052682 stishovite Inorganic materials 0.000 description 10
- 229910052905 tridymite Inorganic materials 0.000 description 10
- 238000006243 chemical reaction Methods 0.000 description 7
- 229910052757 nitrogen Inorganic materials 0.000 description 6
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Inorganic materials [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 6
- 230000007547 defect Effects 0.000 description 5
- 230000008021 deposition Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 238000005272 metallurgy Methods 0.000 description 5
- 239000001301 oxygen Substances 0.000 description 5
- 229910052760 oxygen Inorganic materials 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 230000005587 bubbling Effects 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 229920005591 polysilicon Polymers 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 3
- 230000003667 anti-reflective effect Effects 0.000 description 3
- 239000008367 deionised water Substances 0.000 description 3
- 229910021641 deionized water Inorganic materials 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 239000007921 spray Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 238000009792 diffusion process Methods 0.000 description 2
- 238000005530 etching Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000000623 plasma-assisted chemical vapour deposition Methods 0.000 description 2
- 238000005215 recombination Methods 0.000 description 2
- 230000006798 recombination Effects 0.000 description 2
- 238000007650 screen-printing Methods 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 101001073212 Arabidopsis thaliana Peroxidase 33 Proteins 0.000 description 1
- 101001123325 Homo sapiens Peroxisome proliferator-activated receptor gamma coactivator 1-beta Proteins 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 241000646414 Malcolmia africana Species 0.000 description 1
- IOVCWXUNBOPUCH-UHFFFAOYSA-N Nitrous acid Chemical compound ON=O IOVCWXUNBOPUCH-UHFFFAOYSA-N 0.000 description 1
- 102100028961 Peroxisome proliferator-activated receptor gamma coactivator 1-beta Human genes 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 229910018557 Si O Inorganic materials 0.000 description 1
- 229910008062 Si-SiO2 Inorganic materials 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229910006403 Si—SiO2 Inorganic materials 0.000 description 1
- FRIKWZARTBPWBN-UHFFFAOYSA-N [Si].O=[Si]=O Chemical compound [Si].O=[Si]=O FRIKWZARTBPWBN-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000005280 amorphization Methods 0.000 description 1
- 239000006117 anti-reflective coating Substances 0.000 description 1
- 230000008033 biological extinction Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 238000005247 gettering Methods 0.000 description 1
- 230000009931 harmful effect Effects 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 238000000053 physical method Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910001415 sodium ion Inorganic materials 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
- 238000001039 wet etching Methods 0.000 description 1
- 238000009279 wet oxidation reaction Methods 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
- H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
- H01L31/186—Particular post-treatment for the devices, e.g. annealing, impurity gettering, short-circuit elimination, recrystallisation
- H01L31/1868—Passivation
-
- 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 provides a preparation method of a silicon dioxide passive film of a crystalline silicon solar cell, which comprises the following steps: (1) cleaning and texturing the surface of the silicon wafer, diffusing and making PN junctions, and removing edge junctions and surface phosphorosilicate glass; (2) carrying out first oxidation treatment on the silicon wafer treated in the step (1); (3) carrying out second oxidation treatment on the silicon wafer treated in the step (2); (4) and (4) depositing at least two silicon nitride films with different refractive indexes and thicknesses on the surface of the silicon wafer treated in the step (3). The preparation method disclosed by the invention is applied to the polycrystalline silicon battery, so that good passivation effect on the surface of the battery can be achieved, and the efficiency loss of the battery caused by compounding is reduced; the leakage current of the battery can be effectively reduced from the battery process end, the PID resistance of the battery is improved, the corrosion resistance and the moisture resistance of the battery can be enhanced, and the service life of the battery is prolonged.
Description
Technical Field
The invention relates to the technical field of crystalline silicon solar cell preparation, in particular to a preparation method of a silicon dioxide passivation film of a crystalline silicon solar cell.
Background
Surface problems have been an important research topic for semiconductor devices. The surface problem is particularly important for solar cells with shallow junction characteristics, which not only affect the stability of the cell, but also the recombination of surface carriers can severely affect the efficiency of the cell.
For the polysilicon material purified by a physical method, because more metal impurities and micro-defects such as grain boundaries with higher density, dislocation and the like exist, the metal impurities and the defects are all likely to form a composite center finally, so that the minority carrier lifetime of the material is obviously shorter than that of the polysilicon purified by a chemical method. In order to prolong the minority carrier lifetime of a polycrystalline silicon original piece purified by a physical metallurgy method, the method commonly adopted at present is to carry out high-temperature phosphorus gettering treatment of about 950 ℃ on a silicon wafer before a solar cell is manufactured, but new defects are generated in a silicon body, so that the performance of the cell is influenced, and the conversion efficiency of the cell is reduced.
Therefore, good surface passivation has become an indispensable condition for the preparation of high-efficiency physical metallurgy polycrystalline silicon cells from the aspect of cell preparation. At present, two general methods are applicable to the surface passivation of the high-efficiency crystalline silicon solar cell: PECVD silicon nitride passivation and thermal oxidation of SiO2And (5) passivating.
Currently, polysilicon solar cell manufacturers primarily utilize silicon nitride (SiN)x) As a passive anti-reflective film, this is also the only material in the PV industry that can achieve simultaneous cell surface passivation, bulk passivation and surface anti-reflection under one-step process conditions. However, SiNxThe Si structure has high interface state density and large interface stress, and the silicon nitride has poor adhesion to the silicon surface, which affects the passivation effect of the battery surface. And the SiNx passivation antireflection film layer on the surface of the traditional crystalline silicon battery almost seriously attenuates PID of the battery assembly due to lower refractive index. For a physical metallurgy polysilicon battery with poor material quality and large leakage current, the PID phenomenon is more serious. More crystalline silicon cell manufacturers have developed cells with resistance to PID fading by balancing the relationship of increasing the refractive index of the antireflective layer and not decreasing cell efficiency. In order to pursue PID Free, SiNx with a high Si/N ratio is adopted to improve the refractive index of a passivated antireflection film layer, so that the conversion efficiency of the crystalline silicon battery is reduced by 1-2% compared with that of a conventional process.
Document "SiN for crystalline silicon solar cellxH/thermal oxidation of SiO2Study on surface passivation characteristics of double-layer structure (Zhoucyland, donghuang, wang wen shui, Zhao Lei, Li Hai Ling, cun hong, tenth China solar photovoltaic conference collect, pages 46-50) and Chinese patent "a method for preparing a PN junction and a crystalline silicon solar cell with surface passivation" (CN103618028A) both utilize thermal oxidation method to prepare SiO2Passivating the film and obtaining good effect. The thermal oxidation passivation technology is characterized in that partial dangling bonds of silicon are saturated by amorphization of the surface of a silicon wafer, the interface state can be reduced due to Si-O valence bond matching at a silicon dioxide-silicon interface, and Si-SiO2The recombination rate at the interface is also greatly reduced. Silicon dioxide passivated PERC, PERL cellsA higher conversion efficiency is obtained. However, this method has obvious disadvantages, firstly, the thermal oxidation is a high temperature process, generally the oxidation temperature needs to reach over 900 ℃, and when the oxidation is carried out at 1100-1200 ℃, the interface state density is very low. The high temperature has no great influence on the high-quality Fz monocrystalline silicon piece, but for the physical metallurgy polycrystalline silicon piece with poor material quality, the long-time high temperature can increase the dislocation density in the body and excite other new defects, so that the minority carrier lifetime is obviously reduced, and meanwhile, the concentration of a substrate diffusion layer is redistributed in the high temperature process, so that the performance of the battery is reduced. If the film is used as an antireflection film, the thickness of the film is about 110nm, longer oxidation time is needed, and the refractive index of silicon dioxide is lower than the optimal refractive index required by an antireflection film of a solar cell.
In order to improve the disadvantages of long-term high-temperature oxidation, wet-oxygen oxidation (M.stocks and A.C.A.C.surface conversion stability of thermal oxidation multicrystalline silicon [ C ]. in Proceedings of the 2nd World Conference on photo Energy conversion.1998: 1623-; the rapid thermal oxidation adopts a tungsten lamp for heating, the process temperature needs to reach about 1000 ℃, and the oxidation speed is very high. However, the passivation effect of the wet oxidation and the rapid thermal oxidation is not ideal, and although the oxidation process time is shortened and the oxidation temperature is reduced, the temperature is still higher than 850 ℃, which also belongs to a high-temperature process, and a heat treatment is required after the oxidation to obtain a good passivation effect, so that the large-scale application is greatly limited.
Disclosure of Invention
The invention aims to provide a preparation method of a silicon dioxide passivation film of a crystalline silicon solar cell aiming at the defects in the prior art.
The purpose of the invention can be realized by the following technical scheme:
a preparation method of a silicon dioxide passivation film of a crystalline silicon solar cell comprises the following steps:
(1) cleaning and texturing the surface of the silicon wafer, diffusing and making PN junctions, and removing edge junctions and surface phosphorosilicate glass;
(2) carrying out first oxidation treatment on the silicon wafer treated in the step (1);
(3) carrying out second oxidation treatment on the silicon wafer treated in the step (2);
(4) and (4) depositing at least two silicon nitride films with different refractive indexes and thicknesses on the surface of the silicon wafer treated in the step (3).
In one embodiment of the production method of the present invention, the first oxidation treatment includes: and (3) soaking the silicon wafer in a mixed solution of nitric acid and hydrochloric acid for 15-45 minutes, and then rinsing and drying.
In another embodiment of the production method of the present invention, the volume ratio of nitric acid and hydrochloric acid in the mixed solution is HNO3HCl is 20-55: 1-3, the mass concentration of nitric acid is 65-70%, and the mass concentration of hydrochloric acid is 36%.
In another embodiment of the production method of the present invention, the second oxidation treatment comprises: and putting the silicon wafer into an oxidation furnace for thermal oxidation treatment.
In another embodiment of the production method of the present invention, the thermal oxidation treatment is continued for 15 to 60 minutes.
In another embodiment of the preparation method of the present invention, the furnace temperature of the thermal oxidation treatment is 450-.
In another embodiment of the production method of the present invention, the first silicon nitride film and the second silicon nitride film are sequentially deposited on the surface of the silicon wafer subjected to the treatment of the step (3).
In another embodiment of the method of manufacturing the present invention, the first silicon nitride film has a thickness of 21 to 26nm and a refractive index of 2.79 to 2.92, and the second silicon nitride film has a thickness of 56 to 60nm and a refractive index of 1.9 to 2.0.
In another embodiment of the production method of the present invention, a first silicon nitride film, a second silicon nitride film, and a third silicon nitride film are sequentially deposited on the surface of the silicon wafer subjected to the step (3).
In another embodiment of the preparation method of the present invention, the first silicon nitride film has a thickness of 27 to 33nm and a refractive index of 2.6 to 2.8, the second silicon nitride film has a thickness of 21 to 29nm and a refractive index of 2.1 to 2.5, and the third silicon nitride film has a thickness of 47 to 56nm and a refractive index of 1.9 to 2.1.
The preparation method disclosed by the invention is applied to the polycrystalline silicon battery, so that good passivation effect on the surface of the battery can be achieved, and the efficiency loss of the battery caused by compounding is reduced; the leakage current of the battery can be effectively reduced from the battery process end, the PID resistance of the battery is improved, the corrosion resistance and the moisture resistance of the battery can be enhanced, and the service life of the battery is prolonged.
Detailed Description
The technical solution of the present invention is further explained below according to specific embodiments. The scope of protection of the invention is not limited to the following examples, which are set forth for illustrative purposes only and are not intended to limit the invention in any way.
The preparation method of the silicon dioxide passivation film of the crystalline silicon solar cell comprises the following steps:
(1) cleaning and texturing the surface of the silicon wafer, diffusing and making PN junctions, and removing edge junctions and surface phosphorosilicate glass;
(2) carrying out first oxidation treatment on the silicon wafer treated in the step (1);
(3) carrying out second oxidation treatment on the silicon wafer treated in the step (2);
(4) and (4) depositing at least two silicon nitride films with different refractive indexes and thicknesses on the surface of the silicon wafer treated in the step (3).
The silicon wafer used by the invention can be a physical metallurgy polycrystalline silicon wafer, the resistivity is 0.6-3 omega cm, and the removal of the edge junction and the surface phosphorosilicate glass can be carried out by wet etching.
Firstly, the silicon wafer is treated by first oxidation treatmentThe chemical treatment comprises the following steps: firstly, the silicon chip is treated with HNO3Oxidation treatment in solution containing HNO as main component3The concentration is 65-70%, the HCl concentration is 36%, and the HNO is in accordance with the volume ratio31-3 parts of HCl, reacting for 15-45 min, taking out the silicon wafer, rinsing for 5-15 min in an overflow bubbling tank filled with deionized water, and then cleaning for 3-10 min in a spray cleaning tank; and finally, putting the obtained silicon wafer into a drying machine, baking under the protection of nitrogen and drying.
Placing the silicon chip in HNO3+ oxidation in HCl solution with HNO3The oxidation of the silicon wafer is to react on the surface of the silicon wafer to generate silicon dioxide, and simultaneously, the reaction byproduct of nitrogen oxide is combined with water to generate nitrous acid, so that the silicon wafer has strong oxidation, and finally, a thin compact silicon dioxide film can be formed on the front surface and the back surface of the silicon wafer.
Secondly, carrying out second oxidation treatment on the silicon wafer, wherein the second oxidation treatment comprises the following steps: and putting the silicon wafer into an oxidation furnace for thermal oxidation treatment. The process conditions are as follows: keeping the temperature in the furnace at 550-750 ℃, introducing oxygen at 6000-19000 sccm, introducing nitrogen at 8000-26000 sccm, and oxidizing for 30-45 min.
When the second oxidation treatment is carried out, the silicon wafer is subjected to heat treatment by adopting a low-temperature thermal oxidation method of 450-750 ℃, so that the thickness of the silicon dioxide film is increased, the compactness is improved, the surface of the silicon wafer is well passivated, the efficiency loss of the battery caused by compounding is reduced, the phenomenon that the minority carrier lifetime is obviously reduced due to the fact that the dislocation density in the body is increased and other new defects are excited in the high-temperature process is avoided, and meanwhile, the redistribution of the concentration of the substrate diffusion layer caused in the high-temperature process is also avoided. And a layer of ultrathin silicon dioxide layer can be formed on the back of the battery at the same time, so that the back of the battery is passivated to a certain extent, and the utilization efficiency of the long wave on the back surface of the battery is improved.
Depositing at least two silicon nitride films on the silicon dioxide film by using a PECVD method to prepare SiO2-SiNxThe laminated structure combines the good interface property between silicon dioxide and silicon and the excellent electrical property with the chemical inertness and low permeability of silicon nitride filmThe ratios are combined to form a stable passivated antireflective structure.
When two layers of silicon nitride films are deposited, the first silicon nitride film has a thickness of 21-26 nm and a refractive index of 2.79-2.92, and the second silicon nitride film has a thickness of 56-60 nm and a refractive index of 1.9-2.0.
When three silicon nitride films are deposited, the first silicon nitride film has a thickness of 27 to 33nm and a refractive index of 2.6 to 2.8, the second silicon nitride film has a thickness of 21 to 29nm and a refractive index of 2.1 to 2.5, and the third silicon nitride film has a thickness of 47 to 56nm and a refractive index of 1.9 to 2.1.
SiO in the structure2The density of-Si interface states is higher than that of SiNxLow density of-Si interface states to SiO2-SiNxThe laminated film has SiNxThe film has hydrogen passivation effect and lower SiO content2the-Si interface state density combines the advantages of the two and shows better passivation and antireflection effects. In addition, silicon dioxide has a smaller coefficient of thermal expansion than silicon, SiNx-SiO2The stress at the interface is higher than that of SiNxsmall-Si interface, SiNx-SiO2Lower SiO2The layer may also improve SiNxThe adhesive force of (a) forms a continuous interface which has better thermal stability at high temperature.
SiO on the surface of the battery2The silicon nitride film is deposited on the oxide film, so that the device is prevented from being contaminated by external sodium ions, and sodium contained in the oxide film can be transferred into the silicon nitride film. In addition, a large number of positive charge centers are created in the silicon dioxide film due to oxygen vacancies, while negative charge centers are present in the silicon nitride film, and thus in the composite SiNx-SiO2In the passivation film, SiO2It is possible for positive charges in the film to be absorbed into SiO2-SiNxAt the interface, this contributes to the control of the movable charge. In this structure, SiO2Not only acts as a buffer and mediator, but also acts as a good surface passivation film that is thin enough not to interfere with SiN when combined with an antireflective coatingxAn antireflection film optical system. And the manufactured cell is not easy to corrode and is damp-proof, thereby improving the solar cellThe service life of (2).
In the passivated antireflection structure of the invention, SiO is used2The layer has better conductivity than SiNx layer, and SiO is introduced into the bottom layer2A layer capable of guiding away a part of the enriched external charges to prevent the passive antireflection film from failing due to charge accumulation, and SiO2The passivation layer can also improve the Voc of the battery, obviously reduce the reverse leakage current of the battery, improve the performance and conversion efficiency of the battery and reduce the risk of PID of the battery component. Deposit in the three-layer silicon nitride structure on the silica passive film, the passivation SiNx layer of first layer high refractive index can further reduce PID decay, the SiNx layer of top layer low refractive index can improve the H content of passivation antireflection film, reduce the harmful effects that high refractive index SiNx layer produced Isc and FF, make silver thick liquid can more effectively corrode and wear the passivation antireflection rete, the intermediate level silicon nitride refracting index is moderate, and the membrane is thick less, can play a buffer layer effect between first layer silicon nitride and top layer silicon nitride, reduce the influence that produces high extinction coefficient because of the high refracting index of first layer membrane, and reduce the light reflection between first layer silicon nitride and the top layer silicon nitride interface.
The preparation method disclosed by the invention is compatible with the existing process, has a good effect when being applied to the preparation of the polycrystalline silicon battery, and has the advantages of good passivation and anti-reflection performance of the front surface of the battery, excellent passivation effect of the back surface and capability of improving the utilization efficiency of long waves.
The present invention will be described in further detail with reference to specific examples.
Example 1
(1) Cleaning and texturing the surface of a silicon wafer, diffusing to prepare PN junctions, and etching by a wet method to remove edge junctions and surface phosphorosilicate glass;
(2) carrying out first oxidation treatment on the silicon wafer treated in the step (1);
firstly, the silicon chip is treated with HNO3Oxidation treatment in solution containing HNO as main component3The concentration is 65-70%, the HCl concentration is 36%, and the HNO is in accordance with the volume ratio3The method comprises the steps of (1-3: 20-55) HCl, reacting for 15-45 min, taking out a silicon wafer, rinsing the silicon wafer in an overflow bubbling tank filled with deionized water for 5-15 min, and putting the silicon wafer in the overflow bubbling tankCleaning in a spray cleaning tank for 3-10 min; and finally, putting the obtained silicon wafer into a drying machine, baking under the protection of nitrogen and drying.
(3) Carrying out second oxidation treatment on the silicon wafer treated in the step (2);
putting the silicon wafer into an oxidation furnace for thermal oxidation treatment, wherein the process conditions are as follows: keeping the temperature in the furnace at 550-750 ℃, introducing oxygen at 6000-19000 sccm, introducing nitrogen at 8000-26000 sccm, and oxidizing for 30-45 min.
(4) And (4) depositing three silicon nitride films with different refractive indexes and thicknesses on the surface of the silicon wafer processed in the step (3).
Firstly, depositing a first silicon nitride film on silicon dioxide, wherein the process conditions are as follows: NH (NH)3Flow rate 3000sccm, SiH4The flow rate is 1000sccm, and the control pressure is 197 Pa; the radio frequency power is 4000W, and the deposition time is 100-120 s; obtaining a first silicon nitride film with the thickness of 27-33 nm and the refractive index of 2.6-2.8;
and then depositing a second silicon nitride film on the first silicon nitride film, wherein the process conditions are as follows: NH (NH)3Flow rate 3429sccm, SiH4The flow rate is 571sccm, and the pressure is controlled to be 186 Pa; the radio frequency power is 4000W, and the deposition time is 70-90 s; obtaining a second silicon nitride film with the thickness of 21-29 nm and the refractive index of 2.1-2.5;
and finally depositing a third silicon nitride film on the second silicon nitride film, wherein the process conditions are as follows: NH (NH)3Flow rate 3750sccm, SiH4The flow rate is 250sccm, and the control pressure is 183 Pa; the radio frequency power is 4000W, and the deposition time is 470 and 480 s; obtaining a third silicon nitride film with a thickness of 47-56 nm and a refractive index of 1.9-2.1.
The obtained silicon chip is subjected to screen printing, sintering, testing and sorting to obtain the battery performance parameters shown in table 1.
Example 2
(1) Cleaning and texturing the surface of a silicon wafer, diffusing to prepare PN junctions, and etching by a wet method to remove edge junctions and surface phosphorosilicate glass;
(2) carrying out first oxidation treatment on the silicon wafer treated in the step (1);
firstly, the silicon chip is treated with HNO3Oxidation treatment in solution containing HNO as main component3The concentration is 65-70%, the HCl concentration is 36%, and the HNO is in accordance with the volume ratio3The method comprises the following steps of (1) adding HCl 25-50: 1-3, reacting for 15-45 min, taking out a silicon wafer, putting the silicon wafer into an overflow bubbling tank containing deionized water, rinsing for 5-15 min, and putting the silicon wafer into a spray cleaning tank for cleaning for 3-10 min; and finally, putting the obtained silicon wafer into a drying machine, baking under the protection of nitrogen and drying.
(3) Carrying out second oxidation treatment on the silicon wafer treated in the step (2);
putting the silicon wafer into an oxidation furnace for thermal oxidation treatment, wherein the process conditions are as follows: keeping the temperature in the furnace at 450-650 ℃, introducing oxygen at 6000-19000 sccm, introducing nitrogen at 8000-26000 sccm, and oxidizing for 30-60 min.
(4) And (4) depositing two silicon nitride films with different refractive indexes and thicknesses on the surface of the silicon wafer processed in the step (3).
Firstly, depositing a first silicon nitride film on silicon dioxide, wherein the process conditions are as follows: NH (NH)3Flow rate was 3350sccm/min, SiH4The flow rate is 650sccm/min, and the control pressure is 195 Pa; the radio frequency power is 2500W, and the deposition time is 180-200 s; obtaining a first silicon nitride film with the thickness of 21-26 nm and the refractive index of 2.79-2.92;
and then depositing a second silicon nitride film on the first silicon nitride film, wherein the process conditions are as follows: NH (NH)3Flow rate 3700sccm/min, SiH4The flow rate is 300sccm/min, and the pressure is controlled to be 200 Pa; the radio frequency power is 2500W, and the deposition time is 450-480 s; obtaining a second silicon nitride film with a thickness of 56-60 nm and a refractive index of 1.9-2.0.
The performance parameters of the obtained cell are shown in table 2 after the obtained silicon chip is subjected to screen printing, sintering, testing and sorting.
Comparative example 1
In comparison with example 1, the battery production process was the same except that the first oxidation treatment and the second oxidation treatment of the present invention were not performed. The electrical performance parameters of the obtained solar cell are shown in table 1.
Comparative example 2
As compared with example 2, the battery production process was the same except that the first oxidation treatment and the second oxidation treatment of the present invention were not performed. The electrical performance parameters of the obtained solar cell are shown in table 2.
TABLE 1 average Electrical Performance parameters of the batteries obtained in example 1 and comparative example 1
Table 2 average electrical property parameters of the batteries obtained in example 2 and comparative example 2
It should be noted by those skilled in the art that the described embodiments of the present invention are merely exemplary and that various other substitutions, alterations, and modifications may be made within the scope of the present invention. Accordingly, the present invention is not limited to the above-described embodiments, but is only limited by the claims.
Claims (8)
1. A preparation method of a silicon dioxide passivation film of a crystalline silicon solar cell comprises the following steps:
(1) cleaning and texturing the surface of the silicon wafer, diffusing and making PN junctions, and removing edge junctions and surface phosphorosilicate glass;
(2) performing first oxidation treatment on the silicon wafer treated in the step (1), wherein the first oxidation treatment comprises the following steps: putting the silicon wafer into a mixed solution of nitric acid and hydrochloric acid to be soaked for 15-45 minutes, and then rinsing and drying the silicon wafer;
(3) and (3) carrying out second oxidation treatment on the silicon wafer processed in the step (2), wherein the second oxidation treatment comprises the following steps: putting the silicon wafer into an oxidation furnace for thermal oxidation treatment, wherein the temperature in the thermal oxidation treatment is 450-750 ℃;
(4) and (4) depositing at least two silicon nitride films with different refractive indexes and thicknesses on the surface of the silicon wafer treated in the step (3).
2. According to claim 1The preparation method comprises the step of mixing the nitric acid and the hydrochloric acid in the mixed solution according to the volume ratio of HNO3HCl is 20-55: 1-3, the mass concentration of nitric acid is 65-70%, and the mass concentration of hydrochloric acid is 36%.
3. The production method according to claim 1, wherein the thermal oxidation treatment lasts for 15 to 60 minutes.
4. The method according to claim 1, wherein a flow rate of oxygen gas is 3000 to 19000sccm and a flow rate of nitrogen gas is 5000 to 26000sccm during the thermal oxidation treatment.
5. The production method according to claim 1, wherein a first silicon nitride film and a second silicon nitride film are sequentially deposited on the surface of the silicon wafer subjected to the step (3).
6. The method according to claim 5, wherein the first silicon nitride film has a thickness of 21 to 26nm and a refractive index of 2.79 to 2.92, and the second silicon nitride film has a thickness of 56 to 60nm and a refractive index of 1.9 to 2.0.
7. The production method according to claim 1, wherein a first silicon nitride film, a second silicon nitride film, and a third silicon nitride film are sequentially deposited on the surface of the silicon wafer subjected to the step (3).
8. The method according to claim 7, wherein the first silicon nitride film has a thickness of 27 to 33nm and a refractive index of 2.6 to 2.8, the second silicon nitride film has a thickness of 21 to 29nm and a refractive index of 2.1 to 2.5, and the third silicon nitride film has a thickness of 47 to 56nm and a refractive index of 1.9 to 2.1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510923285.0A CN105355723B (en) | 2015-12-14 | 2015-12-14 | Preparation method of silicon dioxide passivation film of crystalline silicon solar cell |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510923285.0A CN105355723B (en) | 2015-12-14 | 2015-12-14 | Preparation method of silicon dioxide passivation film of crystalline silicon solar cell |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105355723A CN105355723A (en) | 2016-02-24 |
| CN105355723B true CN105355723B (en) | 2019-12-27 |
Family
ID=55331652
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510923285.0A Expired - Fee Related CN105355723B (en) | 2015-12-14 | 2015-12-14 | Preparation method of silicon dioxide passivation film of crystalline silicon solar cell |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105355723B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107221580B (en) * | 2017-06-15 | 2018-10-12 | 常州亿晶光电科技有限公司 | Promote the battery preparation method of PERC back of the body passivation effects |
| CN107799613A (en) * | 2017-10-17 | 2018-03-13 | 张家港协鑫集成科技有限公司 | Nanometer suede polycrystal silicon cell laminated antireflection film and preparation method thereof and application |
| CN111554771A (en) * | 2019-01-24 | 2020-08-18 | 比亚迪股份有限公司 | Preparation method of solar cell, solar cell and solar cell |
| CN110459615A (en) * | 2019-08-19 | 2019-11-15 | 通威太阳能（成都）有限公司 | A kind of composite dielectric passivation layer structure solar cell and its preparation process |
| CN111564525B (en) * | 2020-05-11 | 2023-06-13 | 江西昌大高新能源材料技术有限公司 | Preparation method of silicon oxide-doped polycrystalline silicon composite film for crystalline silicon solar cell |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102916080A (en) * | 2012-10-22 | 2013-02-06 | 江苏荣马新能源有限公司 | Method for preparing double-layered antireflection films for crystalline silicon solar cells |
| CN103165754A (en) * | 2013-03-25 | 2013-06-19 | 泰通(泰州)工业有限公司 | Preparation process for solar cell resisting potential induced degradation |
| CN104659150A (en) * | 2015-02-09 | 2015-05-27 | 浙江晶科能源有限公司 | Preparation method of crystalline silicon solar battery multi-layer antireflection film |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104064622A (en) * | 2013-03-21 | 2014-09-24 | 晶科能源有限公司 | Solar energy battery resisting potential-induced attenuation and manufacture method thereof |
-
2015
- 2015-12-14 CN CN201510923285.0A patent/CN105355723B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102916080A (en) * | 2012-10-22 | 2013-02-06 | 江苏荣马新能源有限公司 | Method for preparing double-layered antireflection films for crystalline silicon solar cells |
| CN103165754A (en) * | 2013-03-25 | 2013-06-19 | 泰通(泰州)工业有限公司 | Preparation process for solar cell resisting potential induced degradation |
| CN104659150A (en) * | 2015-02-09 | 2015-05-27 | 浙江晶科能源有限公司 | Preparation method of crystalline silicon solar battery multi-layer antireflection film |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105355723A (en) | 2016-02-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101548395B (en) | Method of manufacturing crystalline silicon solar cells with improved surface passivation | |
| WO2021031500A1 (en) | Solar cell with composite dielectric passivation layer structure, and preparation process therefor | |
| EP4027395A1 (en) | Efficient back passivation crystalline silicon solar cell and manufacturing method therefor | |
| CN105355723B (en) | Preparation method of silicon dioxide passivation film of crystalline silicon solar cell | |
| CN110459642B (en) | Passivated contact cell and method of making same | |
| CN109004038B (en) | Solar cell, preparation method thereof and photovoltaic module | |
| CN103026494A (en) | Silicon solar cell having boron diffusion layer and method for manufacturing same | |
| CN205194711U (en) | Physical metallurgy polycrystalline silicon solar cell's passivation subtracts reflection configuration | |
| CN111640823B (en) | N-type passivated contact battery and preparation method thereof | |
| Balaji et al. | Surface passivation schemes for high-efficiency c-Si solar cells-A review | |
| WO2023202079A1 (en) | Preparation method for solar cell and solar cell | |
| CN113948611A (en) | P-type IBC battery, preparation method and assembly thereof, and photovoltaic system | |
| CN116741877A (en) | TBC battery preparation method and TBC battery | |
| CN111524999A (en) | Preparation method of tunneling oxidation passivation battery | |
| CN110571303A (en) | Preparation method of P-type crystalline silicon cell | |
| CN112768534A (en) | Silicon oxide passivated PERC double-sided battery and preparation method thereof | |
| WO2022110613A1 (en) | Perc cell preparation method | |
| CN210092098U (en) | Solar cell with composite dielectric passivation layer structure | |
| CN117038799A (en) | BC battery preparation method and BC battery | |
| CN110534614B (en) | Preparation method of P-type crystalline silicon cell | |
| CN101499502A (en) | Crystalline silicon solar cell and its passivation method | |
| CN110965044A (en) | Dielectric passivation film for reducing electroattenuation of PERC (Positive-negative resistance) battery and preparation method thereof | |
| CN112713216B (en) | Preparation method of laminated antireflection film of solar cell | |
| CN114583016A (en) | TOPCon battery and preparation method thereof | |
| CN209880634U (en) | Back passivation structure of solar cell |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20191227 Termination date: 20201214 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |