CN116864568A - Preparation method of TOPCon solar cell with double-sided SE (selective emitter and collector) - Google Patents
Preparation method of TOPCon solar cell with double-sided SE (selective emitter and collector) Download PDFInfo
- Publication number
- CN116864568A CN116864568A CN202310787747.5A CN202310787747A CN116864568A CN 116864568 A CN116864568 A CN 116864568A CN 202310787747 A CN202310787747 A CN 202310787747A CN 116864568 A CN116864568 A CN 116864568A
- Authority
- CN
- China
- Prior art keywords
- sided
- solar cell
- double
- doping
- laser
- 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.)
- Granted
Links
- 238000002360 preparation method Methods 0.000 title abstract description 9
- 229910021417 amorphous silicon Inorganic materials 0.000 claims abstract description 48
- 238000009792 diffusion process Methods 0.000 claims abstract description 46
- 238000000034 method Methods 0.000 claims abstract description 37
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims abstract description 25
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims abstract description 25
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 25
- 239000011574 phosphorus Substances 0.000 claims abstract description 25
- 229910052796 boron Inorganic materials 0.000 claims abstract description 23
- 230000008569 process Effects 0.000 claims abstract description 19
- 238000007747 plating Methods 0.000 claims abstract description 17
- 238000002347 injection Methods 0.000 claims abstract description 16
- 239000007924 injection Substances 0.000 claims abstract description 16
- 238000004140 cleaning Methods 0.000 claims abstract description 14
- 238000004518 low pressure chemical vapour deposition Methods 0.000 claims abstract description 8
- 238000005498 polishing Methods 0.000 claims abstract description 8
- 238000001465 metallisation Methods 0.000 claims abstract description 4
- 238000000623 plasma-assisted chemical vapour deposition Methods 0.000 claims abstract 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 34
- 229910052710 silicon Inorganic materials 0.000 claims description 34
- 239000010703 silicon Substances 0.000 claims description 34
- 238000000151 deposition Methods 0.000 claims description 17
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 11
- 230000008021 deposition Effects 0.000 claims description 11
- 229910052814 silicon oxide Inorganic materials 0.000 claims description 11
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 10
- 229910052709 silver Inorganic materials 0.000 claims description 10
- 239000004332 silver Substances 0.000 claims description 10
- 125000004437 phosphorous atom Chemical group 0.000 claims description 9
- 238000007639 printing Methods 0.000 claims description 8
- 229910052751 metal Inorganic materials 0.000 claims description 7
- 239000002184 metal Substances 0.000 claims description 7
- 229910004205 SiNX Inorganic materials 0.000 claims description 6
- 230000000694 effects Effects 0.000 claims description 6
- 229910052760 oxygen Inorganic materials 0.000 claims description 6
- 239000001301 oxygen Substances 0.000 claims description 6
- 230000005641 tunneling Effects 0.000 claims description 5
- 239000003513 alkali Substances 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 4
- 239000000126 substance Substances 0.000 claims description 4
- 229910052593 corundum Inorganic materials 0.000 claims description 3
- 230000003287 optical effect Effects 0.000 claims description 3
- 238000007650 screen-printing Methods 0.000 claims description 3
- 238000005245 sintering Methods 0.000 claims description 3
- 238000001039 wet etching Methods 0.000 claims description 3
- 238000004804 winding Methods 0.000 claims description 3
- 229910001845 yogo sapphire Inorganic materials 0.000 claims description 3
- 238000005516 engineering process Methods 0.000 abstract description 15
- 230000007547 defect Effects 0.000 abstract description 2
- 238000004519 manufacturing process Methods 0.000 description 17
- 239000002002 slurry Substances 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 3
- 229910052581 Si3N4 Inorganic materials 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000004886 process control Methods 0.000 description 2
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000002161 passivation Methods 0.000 description 1
- 238000005215 recombination Methods 0.000 description 1
- 230000006798 recombination Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000006467 substitution 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
- H01L31/1804—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof comprising only elements of Group IV of the Periodic Table
-
- 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
- H01L31/0248—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 characterised by their semiconductor bodies
- H01L31/0352—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 characterised by their semiconductor bodies characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions
- H01L31/035272—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 characterised by their semiconductor bodies characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions characterised by at least one potential jump barrier or surface barrier
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
- H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by potential barriers
- H01L31/068—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by potential barriers the potential barriers being only of the PN homojunction type, e.g. bulk silicon PN homojunction solar cells or thin film polycrystalline silicon PN homojunction solar cells
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
- H01L31/186—Particular post-treatment for the devices, e.g. annealing, impurity gettering, short-circuit elimination, recrystallisation
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Sustainable Development (AREA)
- Photovoltaic Devices (AREA)
Abstract
The invention provides a preparation method of a TOPCon solar cell with double-sided SE, and relates to the technical field of TOPCon solar cell processing. The preparation of the TOPCon solar cell with the double-sided SE mainly comprises the steps of cleaning and texturing, pre-boron doping, front laser SE, post-boron doping, BSG removal, basic polishing, LPCVD amorphous silicon plating, primary phosphorus diffusion, back laser SE, secondary phosphorus diffusion, PSG removal, RCA cleaning, PECVD (plasma enhanced chemical vapor deposition) antireflection layer plating, front and back metallization, electric injection or light injection and the like. The invention overcomes the defects of the prior art, optimizes the P-expansion process on the basis of the prior TOPCon battery structure and equipment, introduces a laser grooving technology, and superimposes the secondary P-expansion to form a selective emitter N++ region, thereby improving the efficiency, and simultaneously having relatively simple process, less cost increase and large window.
Description
Technical Field
The invention relates to the technical field of TOPCon solar cell processing, in particular to a method for preparing a TOPCon solar cell with double-sided SE.
Background
At present, the preparation of the high-efficiency TOPCon battery basically adopts the following process route: groove texturing-front boron doping (silicon wafer back-to-back) -SE doping (selective area laser doping) -back boron doping (silicon wafer back-to-back) -back (silicon wafer no diffusion side), edge-out BSG-alkali polishing+front-out BSG-back LPCVD amorphous silicon plating-back P diffusion-front and edge-out PSG-RCA edge and front-out Poly-front alumina deposition+silicon nitride antireflection film deposition (ALD or PECVD two-in-one) -back silicon nitride deposition (PECVD) -back aluminum paste+silver paste printing-front silver paste printing (one-step or step printing) -sintering-electrical injection (or light injection) -testing and sorting.
The laser local doping, namely SE technology, has the main advantages that: 1. the series resistance of the solar cell is reduced, and the FF is improved; 2. surface recombination is reduced, and surface passivation effect is improved; 3. the low concentration diffusion of the surface of the non-heavily doped region improves the short-wave response of the battery and improves the short-circuit current and the open-circuit voltage. However, the advantages are mainly that the application of the SE technology to the front surface (facing the light direction) is very few, and the application of the SE technology to the back light surface of TOPCon batteries is very difficult. The existing manufacturing technology of the back laser SE mainly comprises direct laser doping, laser grooving, superposition secondary poly deposition and secondary P expansion.
The direct laser doping manufacturing technology is characterized in that after P diffusion is carried out on an amorphous silicon layer, the doping source in the PSG after P diffusion is directly carried out by utilizing laser energy, the subsequent process is carried out normally, but as the thickness of the amorphous silicon layer is only 50-200nm, the flatness of the surface PSG is difficult to control, the direct laser doping is carried out, the required laser power control window is narrow, the energy stability requirement is high, the damage to the amorphous silicon layer of a silicon wafer is extremely easy, the risk of the tunneling structure damage caused by the slurry burning through the amorphous silicon layer is further increased, in the laser slotting superposition secondary poly deposition and secondary P diffusion manufacturing technology, thinning treatment is carried out during the manufacturing of amorphous silicon on the back surface, then low-concentration P diffusion is carried out, then the second amorphous silicon layer with thicker is deposited, meanwhile, P diffusion with higher concentration is carried out, after the completion, the second amorphous silicon layer with a non-slurry contact part is removed through laser slotting, the left area is the SE selective emitter, the process is complex, the manufacturing difficulty is increased, the requirements on the front and the back amorphous silicon layer is more difficult to control, and the matching process is more difficult, and the mass production is unfavorable.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a preparation method of a TOPCon solar cell with double-sided SE, which optimizes a P-expansion process based on the existing TOPCon cell structure and equipment, introduces a laser grooving technology, and superimposes a secondary P-expansion to form a selective emitter N++ region.
In order to achieve the above object, the technical scheme of the present invention is realized by the following technical scheme:
a TOPcon solar cell fabrication method of double-sided SE, the fabrication method comprising the steps of:
s1, cleaning and texturing: selecting an N-type silicon wafer for double-sided cleaning and texturing;
s2, pre-boron doping: performing front boron doping on the textured silicon wafer;
s3, front laser SE: selectively heavily doping the front laser SE of the processed silicon wafer;
s4, post boron doping: performing secondary boron doping on the silicon wafer after the process is completed;
s5, BSG removal and basic polishing: removing BSG on the back surface, and performing wet chemical alkali polishing on the back surface, and simultaneously removing the front surface BSG layer;
s6, LPCVD plating amorphous silicon: depositing an SiOx tunneling layer on the back surface of the silicon wafer and then plating an amorphous silicon layer by LPCVD;
s7, primary phosphorus diffusion: performing tubular phosphorus diffusion doping on the back amorphous silicon, adding a post-oxygen treatment step, and depositing a layer of SiOx on the surface;
s8, back laser SE: carrying out slotting treatment on PSG according to a screen printing pattern, and pushing P atoms of a PSG layer to an amorphous silicon layer to form a back SE region;
s9, secondary phosphorus diffusion: the back surface is subjected to secondary tubular phosphorus diffusion, a thicker PSG is blocked in a non-SE area on the back surface, phosphorus atoms are slowly doped, the phosphorus atoms in the SE area on the back surface are rapidly deposited and diffuse into amorphous silicon to form a back surface N++ area, after the deposition is finished, the surface is subjected to post-oxygen treatment, and a SiOx layer is grown on the surface of the N++ area;
s10, cleaning PSG and RCA: removing PSG on the front side and the edge by wet etching, removing the front amorphous silicon layer and residual PSG and BSG layers by RCA cleaning after exposing the front winding plated amorphous silicon layer, and simultaneously removing the back PSG layer completely;
s11, PECVD plating an antireflection layer: plating Al2O3 and SiNx antireflection films on the front surface and plating SiNx antireflection films on the back surface;
s12, front and back metallization: back surface SE pattern printing by back surface aluminum paste and silver paste overprinting; printing front silver paste;
s13, electric injection or optical injection: sintering, electric injection or light injection, testing and sorting to obtain the TOPCon solar cell with double-sided SE.
Preferably, in the step (2), the textured silicon wafer is arranged back to back and then is subjected to boron doping treatment, and the boron doped surface is used as the front surface.
Preferably, in the step (3), the laser SE is selectively heavily doped to heavily dope the contact portion of the metal gate line and the silicon wafer, while the position outside the metal gate line is lightly doped, and the pre-diffusion is performed on the surface of the silicon wafer by a thermal diffusion mode to form light doping; meanwhile, the surface BSG is used as a local laser heavy doping source, and boron atoms in the BSG are secondarily and rapidly diffused to the interface of the BSG and the silicon surface through the local laser thermal effect to form a local heavy doping region.
Preferably, the silicon wafer is continuously subjected to back-to-back mode in the secondary boron doping process in the step (4).
Preferably, the primary phosphorus diffusion in the step (7) is surface light doping.
Preferably, in the step (7), the surface concentration of ECV is 0.3-1×E20, the square resistance is 20-50 Ω/sqr, the junction depth is 0.1-0.2 μm, and the PSG thickness is 0.1-0.5 μm.
Preferably, the secondary phosphorus diffusion in the step (9) is locally heavily doped.
Preferably, in the step (9), the ECV surface concentration of the back non-SE region is 0.5-1.5×20, the square resistance is 30-70 Ω/sqr, the junction depth is 0.15-0.3 μm, the back SE region is a heavily doped n++ region, the ECV surface concentration is 0.8-2.0×20, the square resistance is 20-60 Ω/sqr, the junction depth is 0.2-0.38 μm, and the SiOx layer thickness is 30-150nm.
The invention provides a preparation method of a TOPCon solar cell with double-sided SE, which has the advantages that compared with the prior art:
the invention optimizes the P-diffusion process based on the prior TOPCon battery structure and equipment, firstly carries out low-concentration P diffusion on an amorphous silicon layer, properly increases the P-diffusion PSG thickness, introduces a laser grooving technology, effectively avoids the damage of laser energy to the amorphous silicon layer during laser grooving due to the adjustment of the PSG on the amorphous silicon surface, greatly increases the amorphous silicon layer thickness process window, reduces the laser process control difficulty, greatly increases the selectivity of laser equipment, reduces the purchase cost, thereby reducing the production cost, simultaneously stacks secondary P-diffusion high-temperature promotion, further diffuses the P element in a grooving region into the amorphous silicon layer to form a heavily doped selective emitter N++ region, reduces the serial resistance of Al and silver paste through the heavy doping of local phosphorus element on the back, and improves FF; in addition, back phosphorus diffusion further getters and improves BSF effects, improves open circuit voltage of the battery, and the like. The method has the advantages of improving efficiency, along with relatively simple process, less cost increase, low control difficulty and large window, and effectively realizes that the SE technology is applied to the back surface of the TOPCon battery to improve the battery efficiency.
Description of the drawings:
fig. 1 is a workflow diagram of a TOPcon battery preparation method of the present invention;
fig. 2 is a block diagram of a TOPcon battery prepared according to the present invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions in the embodiments of the present invention will be clearly and completely described in the following in conjunction with the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Examples:
preparation of TOPcon solar cell of double sided SE:
s1, cleaning and texturing: selecting an N-type silicon wafer for double-sided cleaning and texturing, and utilizing acid-base chemicals to eliminate organic contamination and metal impurities on the surface of the silicon wafer, so that a pyramid structure is formed on the surface of the monocrystalline silicon wafer, the absorption of sunlight is enhanced, and the reflection is reduced; the monocrystalline silicon piece is a phosphorus doped N-type monocrystalline silicon piece, the resistivity is 0.1-10 omega cm, and the thickness is 100-200um;
s2, pre-boron doping: front boron doping is carried out on the textured silicon wafer back to back, and the boron doped surface is set as the front surface;
s3, front laser SE: selectively heavily doping the front laser SE of the processed silicon wafer, heavily doping the contact part of the metal grid line and the silicon wafer, keeping light doping at the position except the metal grid line, and pre-diffusing the surface of the silicon wafer in a thermal diffusion mode to form light doping; meanwhile, the surface BSG is used as a local laser heavy doping source, and boron atoms in the BSG are secondarily and rapidly diffused to the interface of the BSG and the silicon surface through the local laser thermal effect to form a local heavy doping region;
s4, post boron doping: the silicon wafer after the working procedures are finished is subjected to secondary boron doping in a back-to-back mode;
s5, BSG removal and basic polishing: removing BSG on the back surface, and performing wet chemical alkali polishing on the back surface, and simultaneously removing the front surface BSG layer;
s6, LPCVD plating amorphous silicon: depositing an SiOx tunneling layer on the back surface of the silicon wafer and then plating an amorphous silicon layer by LPCVD;
s7, primary phosphorus diffusion: performing tubular phosphorus diffusion doping on the back amorphous silicon, adding a post-oxygen treatment step, and depositing a layer of SiOx on the surface;
the primary phosphorus diffusion is surface light doping, the ECV surface concentration is 0.3-1 x E20, the sheet resistance value is 20-50 omega/sqr, the junction depth is 0.1-0.2 mu m, and the PSG thickness is 0.1-0.5 mu m;
s8, back laser SE: carrying out slotting treatment on PSG according to a screen printing pattern, and pushing P atoms of a PSG layer to an amorphous silicon layer to form a back SE region;
s9, secondary phosphorus diffusion: the back surface is subjected to secondary tubular phosphorus diffusion, a thicker PSG is blocked in a non-SE area on the back surface, phosphorus atoms are slowly doped, the phosphorus atoms in the SE area on the back surface are rapidly deposited and diffuse into amorphous silicon to form a back surface N++ area, after the deposition is finished, the surface is subjected to post-oxygen treatment, and a SiOx layer is grown on the surface of the N++ area;
the secondary phosphorus diffusion is local heavy doping, the ECV surface concentration of the back non-SE area is 0.5-1.5E 20, the square resistance value is 30-70 omega/sqr, the junction depth is 0.15-0.3 mu m, the back SE area is a heavy doping N++ area, the ECV surface concentration is 0.8-2.0E 20, and the square resistance value is 20-60 omega/sqr. Junction depth is 0.2-0.38 mu m, siOx layer thickness is 30-150nm;
s10, cleaning PSG and RCA: removing PSG on the front side and the edge by wet etching, removing the front amorphous silicon layer and residual PSG and BSG layers by RCA cleaning after exposing the front winding plated amorphous silicon layer, and simultaneously removing the back PSG layer completely;
s11, PECVD plating an antireflection layer: plating Al2O3 and SiNx antireflection films on the front surface and plating SiNx antireflection films on the back surface;
s12, front and back metallization: back surface SE pattern printing by back surface aluminum paste and silver paste overprinting; printing front silver paste;
s13, electric injection or optical injection: sintering, electric injection or light injection, testing and sorting to obtain the TOPCon solar cell with double-sided SE.
The TOPCon solar cell structure shown in FIG. 2 can be obtained by the above processing steps.
The existing manufacturing technology of the back laser SE mainly comprises direct laser doping, laser grooving, superposition of secondary poly deposition and secondary P diffusion, and the direct laser doping manufacturing technology is that after P diffusion is carried out on an amorphous silicon layer, laser energy is utilized to directly carry out secondary promotion on a doping source in the PSG after the P diffusion, the subsequent process is normally carried out, and the process steps are simple. However, the thickness of the amorphous silicon layer is only 50-200nm, the flatness of the surface PSG is difficult to control, the required laser power control window is narrow, the energy stability requirement is high, the amorphous silicon layer of the silicon wafer is extremely easy to damage, the risk of the tunneling structure damage caused by slurry burning through the amorphous silicon layer is further increased, in the technology of laser grooving, superposition of secondary poly deposition and secondary P expansion manufacturing, thinning treatment is carried out when the back amorphous silicon is manufactured, then low-concentration P diffusion is carried out, then the second thicker amorphous silicon deposition is carried out, meanwhile, higher-concentration P diffusion is carried out, after the completion, the second amorphous silicon layer of the non-slurry contact part is removed through laser grooving, the left area is the SE selective emitter, the manufacturing process flow is complicated, the steps are complex, the requirement on the front and back manufacturing process matching is higher, the control difficulty is higher, and the mass production is not beneficial to leading-in production. The invention aims to optimize the P diffusion process on the basis of the existing TOPCon battery structure and equipment, firstly, the P diffusion process is carried out on an amorphous silicon layer, the P diffusion process is carried out, the PSG thickness is properly increased, the laser grooving technology is introduced, as the PSG on the amorphous silicon surface is adjusted, the damage of laser energy to the amorphous silicon layer during laser grooving is effectively avoided, the amorphous silicon layer thickness process window is enlarged, the laser process control difficulty is also reduced, the selectivity to laser equipment is greatly increased, the purchase cost is reduced, thereby reducing the production cost, meanwhile, the P element in the grooving region is further diffused to the amorphous silicon layer by overlapping the P diffusion process of the secondary P diffusion process, forming a heavily doped selective emitter N++ region, and the serial resistance of Al and silver paste is reduced by the back local phosphorus element heavy doping, thereby improving FF; in addition, back phosphorus diffusion further getters and improves BSF effects, improves open circuit voltage of the battery, and the like. The method has the advantages of improving efficiency, along with relatively simple process, less cost increase, low control difficulty and large window, and effectively realizes that the SE technology is applied to the back surface of the TOPCon battery to improve the battery efficiency.
It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
The above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims (8)
1. A method for preparing a TOPcon solar cell with double-sided SE, which is characterized by comprising the following steps:
s1, cleaning and texturing: selecting an N-type silicon wafer for double-sided cleaning and texturing;
s2, pre-boron doping: performing front boron doping on the textured silicon wafer;
s3, front laser SE: selectively heavily doping the front laser SE of the processed silicon wafer;
s4, post boron doping: performing secondary boron doping on the silicon wafer after the process is completed;
s5, BSG removal and basic polishing: removing BSG on the back surface, and performing wet chemical alkali polishing on the back surface, and simultaneously removing the front surface BSG layer;
s6, LPCVD plating amorphous silicon: depositing an SiOx tunneling layer on the back surface of the silicon wafer and then plating an amorphous silicon layer by LPCVD;
s7, primary phosphorus diffusion: performing tubular phosphorus diffusion doping on the back amorphous silicon, adding a post-oxygen treatment step, and depositing a layer of SiOx on the surface;
s8, back laser SE: carrying out slotting treatment on PSG according to a screen printing pattern, and pushing P atoms of a PSG layer to an amorphous silicon layer to form a back SE region;
s9, secondary phosphorus diffusion: the back surface is subjected to secondary tubular phosphorus diffusion, a thicker PSG is blocked in a non-SE area on the back surface, phosphorus atoms are slowly doped, the phosphorus atoms in the SE area on the back surface are rapidly deposited and diffuse into amorphous silicon to form a back surface N++ area, after the deposition is finished, the surface is subjected to post-oxygen treatment, and a SiOx layer is grown on the surface of the N++ area;
s10, cleaning PSG and RCA: removing PSG on the front side and the edge by wet etching, removing the front amorphous silicon layer and residual PSG and BSG layers by RCA cleaning after exposing the front winding plated amorphous silicon layer, and simultaneously removing the back PSG layer completely;
s11, PECVD plating an antireflection layer: plating Al2O3 and SiNx antireflection films on the front surface and plating SiNx antireflection films on the back surface;
s12, front and back metallization: back surface SE pattern printing by back surface aluminum paste and silver paste overprinting; printing front silver paste;
s13, electric injection or optical injection: sintering, electric injection or light injection, testing and sorting to obtain the TOPCon solar cell with double-sided SE.
2. The method for preparing the TOPCon solar cell with double-sided SE according to claim 1, which is characterized in that: and (3) setting the textured silicon wafer back to back in the step (2), then carrying out boron doping treatment, and setting the boron doped surface as a front surface.
3. The method for preparing the TOPCon solar cell with double-sided SE according to claim 1, which is characterized in that: in the step (3), the laser SE is selectively and heavily doped to carry out heavy doping at the contact part of the metal grid line and the silicon wafer, and the position outside the metal grid line is kept to be lightly doped, and the surface of the silicon wafer is pre-diffused in a thermal diffusion mode to form light doping; meanwhile, the surface BSG is used as a local laser heavy doping source, and boron atoms in the BSG are secondarily and rapidly diffused to the interface of the BSG and the silicon surface through the local laser thermal effect to form a local heavy doping region.
4. The method for preparing the TOPCon solar cell with double-sided SE according to claim 1, which is characterized in that: and (3) continuously adopting a back-to-back mode for the silicon wafer in the secondary boron doping process in the step (4).
5. The method for preparing the TOPCon solar cell with double-sided SE according to claim 1, which is characterized in that: and (3) performing primary phosphorus diffusion in the step (7) to obtain surface light doping.
6. The method for preparing the TOPCon solar cell with double-sided SE according to claim 5, which is characterized in that: the ECV surface concentration in the step (7) is 0.3-1 x E20, the square resistance value is 20-50 omega/sqr, the junction depth is 0.1-0.2 mu m, and the PSG thickness is 0.1-0.5 mu m.
7. The method for preparing the TOPCon solar cell with double-sided SE according to claim 1, which is characterized in that: and (3) diffusing the secondary phosphorus in the step (9) to be locally heavily doped.
8. The method for preparing the TOPCon solar cell with double-sided SE according to claim 7, which is characterized in that: in the step (9), the ECV surface concentration of the back non-SE area is 0.5-1.5 xE 20, the square resistance is 30-70 omega/sqr, the junction depth is 0.15-0.3 mu m, the back SE area is a heavily doped N++ area, the ECV surface concentration is 0.8-2.0 xE 20, the square resistance is 20-60 omega/sqr, the junction depth is 0.2-0.38 mu m, and the SiOx layer thickness is 30-150nm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310787747.5A CN116864568B (en) | 2023-06-30 | 2023-06-30 | Preparation method of TOPCon solar cell with double-sided SE (selective emitter and collector) |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310787747.5A CN116864568B (en) | 2023-06-30 | 2023-06-30 | Preparation method of TOPCon solar cell with double-sided SE (selective emitter and collector) |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116864568A true CN116864568A (en) | 2023-10-10 |
| CN116864568B CN116864568B (en) | 2024-04-09 |
Family
ID=88235112
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310787747.5A Active CN116864568B (en) | 2023-06-30 | 2023-06-30 | Preparation method of TOPCon solar cell with double-sided SE (selective emitter and collector) |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116864568B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103077975A (en) * | 2013-01-05 | 2013-05-01 | 中山大学 | Low-cost n-type dual-side solar battery and preparation method thereof |
| CN110335919A (en) * | 2019-06-27 | 2019-10-15 | 江苏日托光伏科技股份有限公司 | A method of improving laser phosphorosilicate glass and adulterates battery surface damage from laser |
| CN111524983A (en) * | 2020-04-03 | 2020-08-11 | 常州大学 | Efficient crystalline silicon battery with double-sided selective emitter and preparation method thereof |
| CN112331742A (en) * | 2020-11-10 | 2021-02-05 | 帝尔激光科技(无锡)有限公司 | Selective emitter passivation contact solar cell and preparation method thereof |
| CN112670353A (en) * | 2020-12-17 | 2021-04-16 | 浙江正泰太阳能科技有限公司 | Boron-doped selective emitter battery and preparation method thereof |
-
2023
- 2023-06-30 CN CN202310787747.5A patent/CN116864568B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103077975A (en) * | 2013-01-05 | 2013-05-01 | 中山大学 | Low-cost n-type dual-side solar battery and preparation method thereof |
| CN110335919A (en) * | 2019-06-27 | 2019-10-15 | 江苏日托光伏科技股份有限公司 | A method of improving laser phosphorosilicate glass and adulterates battery surface damage from laser |
| CN111524983A (en) * | 2020-04-03 | 2020-08-11 | 常州大学 | Efficient crystalline silicon battery with double-sided selective emitter and preparation method thereof |
| CN112331742A (en) * | 2020-11-10 | 2021-02-05 | 帝尔激光科技(无锡)有限公司 | Selective emitter passivation contact solar cell and preparation method thereof |
| CN112670353A (en) * | 2020-12-17 | 2021-04-16 | 浙江正泰太阳能科技有限公司 | Boron-doped selective emitter battery and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN116864568B (en) | 2024-04-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| NL2022765B1 (en) | Step-by-Step Doping Method of Phosphorous for High-efficiency and Low-cost Crystalline Silicon Cell | |
| EP2740149B1 (en) | Method for forming patterns of differently doped regions | |
| CN112490325B (en) | Preparation method of solar cell | |
| WO2024000399A1 (en) | Solar cell structure and manufacturing method therefor | |
| CN115132852A (en) | N-type TOPCon solar cell and manufacturing method thereof | |
| CN114639744A (en) | Solar cell and preparation method thereof | |
| CN116666493A (en) | Solar cell manufacturing method and solar cell | |
| CN116722077A (en) | SE structure preparation method and solar cell | |
| WO2012162905A1 (en) | Method for manufacturing back contact crystalline silicon solar cell sheet | |
| CN116581181A (en) | Double-doped layer TOPCON battery structure and preparation method thereof | |
| CN116504858A (en) | TOPCON battery structure with double polysilicon layers and preparation method thereof | |
| CN116632080A (en) | TOPCON battery and preparation method thereof | |
| US20230361227A1 (en) | Laminated passivation structure of solar cell and preparation method thereof | |
| CN114864740A (en) | Double-sided local passivation contact solar cell and manufacturing method thereof | |
| CN116666479B (en) | Efficient selective emitter crystalline silicon battery with double-sided power generation and preparation method thereof | |
| CN117457797A (en) | Preparation method and application of TOPCON battery structure | |
| CN116130558B (en) | Preparation method of novel all-back electrode passivation contact battery and product thereof | |
| CN116469948A (en) | TOPCON battery and preparation method thereof | |
| CN116864568B (en) | Preparation method of TOPCon solar cell with double-sided SE (selective emitter and collector) | |
| CN116314471A (en) | Preparation method of rear SE structure | |
| CN116435385A (en) | TOPCON battery and preparation method thereof | |
| CN116469945A (en) | TOPCON battery and preparation method thereof | |
| US20230136715A1 (en) | Laminated passivation structure of solar cell and preparation method thereof | |
| Ng et al. | Development of p+/n+ polysilicon tunnel junctions compatible for industrial screen printing | |
| CN115799364B (en) | Solar cell |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |