CN114256385A - TBC back contact solar cell and preparation method thereof - Google Patents
TBC back contact solar cell and preparation method thereof Download PDFInfo
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- 230000005641 tunneling Effects 0.000 claims abstract description 52
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- 229910052710 silicon Inorganic materials 0.000 claims abstract description 41
- 239000010703 silicon Substances 0.000 claims abstract description 41
- 229910052581 Si3N4 Inorganic materials 0.000 claims abstract description 31
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims abstract description 31
- 238000002161 passivation Methods 0.000 claims abstract description 21
- 238000000151 deposition Methods 0.000 claims abstract description 19
- 238000004140 cleaning Methods 0.000 claims abstract description 17
- 238000005498 polishing Methods 0.000 claims abstract description 4
- 238000007639 printing Methods 0.000 claims abstract description 4
- 238000000034 method Methods 0.000 claims description 39
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- 238000004519 manufacturing process Methods 0.000 claims description 13
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 13
- 230000003647 oxidation Effects 0.000 claims description 12
- 238000007254 oxidation reaction Methods 0.000 claims description 12
- 238000000623 plasma-assisted chemical vapour deposition Methods 0.000 claims description 12
- 238000011065 in-situ storage Methods 0.000 claims description 7
- 238000005229 chemical vapour deposition Methods 0.000 claims description 6
- 229910052681 coesite Inorganic materials 0.000 claims description 6
- 229910052906 cristobalite Inorganic materials 0.000 claims description 6
- 239000000377 silicon dioxide Substances 0.000 claims description 6
- 229910052682 stishovite Inorganic materials 0.000 claims description 6
- 229910052905 tridymite Inorganic materials 0.000 claims description 6
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 4
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 4
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- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 4
- 229910052796 boron Inorganic materials 0.000 claims description 4
- 229910017604 nitric acid Inorganic materials 0.000 claims description 4
- 229910052698 phosphorus Inorganic materials 0.000 claims description 4
- 239000011574 phosphorus Substances 0.000 claims description 4
- 229910052709 silver Inorganic materials 0.000 abstract description 12
- 239000004332 silver Substances 0.000 abstract description 12
- 229910052751 metal Inorganic materials 0.000 abstract description 11
- 239000002184 metal Substances 0.000 abstract description 11
- 230000006798 recombination Effects 0.000 abstract description 2
- 238000005215 recombination Methods 0.000 abstract description 2
- 239000010410 layer Substances 0.000 description 116
- 239000000758 substrate Substances 0.000 description 17
- 229910021419 crystalline silicon Inorganic materials 0.000 description 13
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 11
- 238000010586 diagram Methods 0.000 description 10
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 10
- 229910004205 SiNX Inorganic materials 0.000 description 7
- 229910020286 SiOxNy Inorganic materials 0.000 description 7
- 229910052814 silicon oxide Inorganic materials 0.000 description 7
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 150000004696 coordination complex Chemical class 0.000 description 3
- 229910052593 corundum Inorganic materials 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
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- 229910001845 yogo sapphire Inorganic materials 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010248 power generation Methods 0.000 description 2
- 239000003513 alkali Substances 0.000 description 1
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- 230000008021 deposition Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
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- H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
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Abstract
The invention discloses a preparation method of a TBC back contact solar cell, which comprises the following steps: growing a first tunneling oxide layer and a p + doped layer on the back of the silicon wafer subjected to texturing cleaning and polishing treatment, then performing first laser film opening and cleaning on the first tunneling oxide layer and the p + doped layer, depositing a first silicon nitride layer, performing second laser film opening and cleaning on the first silicon nitride layer, growing a second tunneling oxide layer and an n + doped layer, depositing a second silicon nitride layer and cleaning; depositing a passivation anti-reflection film on the front side of the silicon wafer; and performing third laser film opening and cleaning on the n + doped layer and the second silicon nitride layer, and printing a back electrode on the corresponding n + doped layer. According to the preparation method of the solar cell, the prepared cell can well improve the current density and open-circuit voltage of the cell; the back adopts the structure of passivation contact, can be fine reduce the metal puncture of silver, reduce the metal recombination of battery.
Description
Technical Field
The invention belongs to the technical field of photovoltaic module production and manufacturing, and particularly relates to a preparation method of a TBC (TBC) back contact solar cell and a solar cell prepared by the preparation method.
Background
Solar cells are the choice of the new era due to their unique advantages. Solar cells, also known as photovoltaic cells, can convert solar energy directly into electrical energy, the principle of which is the photovoltaic effect of semiconductor PN junctions. Low cost and high efficiency are always the continuous pursuits in the process of industrialization of solar cells. Open circuit voltage, current density, and fill factor are key parameters for the efficiency of a crystalline silicon cell. The conventional back contact IBC structure battery has higher short-circuit current (due to no grid line shading on the front surface)>41mA/cm2) (ii) a A passivated contact structure cell, good passivation effect, very low metal recombination and higher open-circuit voltage>735mV)。
Aiming at the defects and advantages of a back contact IBC structure battery and a passivation contact structure battery, the Chinese patent application with the application number of 202110899873.0 discloses a local passivation contact IBC battery structure and a preparation method thereof, and combines the selective passivation contact technology of TOPCon and the mode of heavily doped metal contact area to obtain a novel battery which can ensure that a metal electrode and a silicon substrate form good contact, maintain the integrity of a passivation film and reduce the manufacturing cost of the back contact battery. However, a mask is needed in the preparation method, so that the positioning problem exists, and the yield of the product is reduced.
Disclosure of Invention
In view of the above, in order to overcome the defects of the prior art, the present invention aims to provide a method for preparing a crystalline silicon solar cell with a TBC back contact structure, which simplifies the process flow, improves the cell efficiency, and saves the cell cost.
In order to achieve the purpose, the invention adopts the following technical scheme:
a method for preparing a TBC back contact solar cell, comprising the steps of: growing a first tunneling oxide layer and a p + doped layer on the back of the silicon wafer subjected to texturing cleaning and polishing treatment, then performing first laser film opening and cleaning on the first tunneling oxide layer and the p + doped layer, depositing a first silicon nitride layer, performing second laser film opening and cleaning on the first silicon nitride layer, growing a second tunneling oxide layer and an n + doped layer, depositing a second silicon nitride layer and cleaning; depositing a passivation anti-reflection film on the front side of the silicon wafer; and performing third laser film opening and cleaning on the n + doped layer and the second silicon nitride layer, and printing a back electrode on the corresponding n + doped layer.
According to some preferred embodiments of the present invention, the first tunneling oxide layer and the second tunneling oxide layer are made of SiO2And the thickness of the first tunneling oxide layer and the second tunneling oxide layer is 1-3 nm, and the growth method of the first tunneling oxide layer and the second tunneling oxide layer is a high-temperature thermal oxidation method, a nitric acid oxidation method, an ozone oxidation method or a CVD (chemical vapor deposition) deposition method.
According to some preferred implementation aspects of the invention, the p + doped layer is formed by plate-type or tubular PECVD in-situ doping, and the flow rate of a boron source is 100-1000 sccm during doping; the thickness of the p + doped layer is 40-300 nm.
According to some preferred implementation aspects of the invention, the n + doped layer is formed by adopting plate-type or tubular PECVD (plasma enhanced chemical vapor deposition) in-situ doping, and the flow rate of a phosphorus source is 100-1000 sccm during doping; the thickness of the n + doped layer is 40-300 nm.
According to some preferred embodiments of the present invention, a first annealing step is further provided after the growing of the first tunnel oxide layer and the p + doped layer: the annealing peak temperature is 900-1100 ℃, the annealing time is 30-200 min, and the atmosphere is N2And O2。
According to some preferred embodiments of the present invention, a second annealing step is further provided after the second tunnel oxide layer and the n + doped layer are grown: the annealing peak temperature is 700-900 ℃, the annealing time is 30-200 min, and the atmosphere is N2And O2。
According to some preferred implementation aspects of the present invention, a third tunneling oxide layer is disposed on the back surface of the silicon wafer at a position corresponding to the first laser opening. Because the first laser film opening damages the back of the N-type silicon wafer, the second tunneling oxide layer grows while the third tunneling oxide layer grows on the back of the N-type silicon wafer corresponding to the first groove, the damage of the first laser film opening on the back of the N-type silicon wafer can be repaired, and the quality and the power generation efficiency of the silicon wafer are improved.
According to some preferred implementation aspects of the invention, the laser wavelength of the first laser film opening and the second laser film opening is 532nm, and the laser wavelength of the third laser film opening is 355 nm.
According to some preferred embodiments of the invention, the silicon wafer is an N-type silicon wafer.
Another object of the present invention is to provide a TBC back contact solar cell prepared by the above preparation method.
Compared with the prior art, the invention has the advantages that: according to the preparation method of the solar cell, the front side of the prepared cell is not shielded by any metal grid line, and is not compounded by any doping, so that the current density and the open-circuit voltage of the cell can be well improved; the back adopts the structure of passivation contact, and the metal puncture of silver can be fine reduced, reduces the metal complex of battery, improves the open circuit voltage of battery.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic diagram of a cell structure after step (1) of a method for manufacturing an N-TBC back contact solar cell in an embodiment of the present invention.
FIG. 2 is a schematic diagram of the cell structure after step (2) of the N-TBC back contact solar cell manufacturing method in the embodiment of the present invention.
FIG. 3 is a schematic diagram of the cell structure after step (3) of the N-TBC back contact solar cell manufacturing method in the embodiment of the present invention.
FIG. 4 is a schematic diagram of the cell structure after step (4) of the method for manufacturing an N-TBC back contact solar cell in the embodiment of the present invention.
FIG. 5 is a schematic diagram of the cell structure after step (5) of the method for manufacturing an N-TBC back contact solar cell in the embodiment of the present invention.
FIG. 6 is a schematic diagram of the cell structure after step (6) of the method for manufacturing an N-TBC back contact solar cell in the embodiment of the present invention.
FIG. 7 is a schematic diagram of the cell structure after step (7) of the method for manufacturing an N-TBC back contact solar cell in the embodiment of the present invention.
FIG. 8 is a schematic diagram of the cell structure after step (8) of the method for manufacturing an N-TBC back contact solar cell in the embodiment of the present invention.
Fig. 9 is a schematic diagram of the cell structure after step (9) of the preparation method of the N-TBC back contact solar cell in the embodiment of the present invention.
FIG. 10 is a schematic structural diagram of an N-TBC back contact solar cell in an embodiment of the present invention.
Wherein the reference numerals include: the structure comprises an N-type silicon wafer-1, a front passivation anti-reflection layer-2, a first tunneling oxide layer-3, a p + doped layer-4, a first groove-5, a first silicon nitride layer-6, a second groove-7, a second tunneling oxide layer-8, a third tunneling oxide layer-9, an N + doped layer-10, a second silicon nitride layer-11, a third groove-12 and a silver electrode-13.
Detailed Description
In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not a whole embodiment. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
EXAMPLE 1N-TBC Back contact solar cell
As shown in fig. 1 to 10, the N-TBC back contact solar cell in this embodiment includes an N-type silicon wafer 1, a passivation anti-reflection layer deposited on the front surface of the N-type silicon wafer 1, a first tunneling oxide layer 3 disposed on the back surface of the N-type silicon wafer 1, a p + doping layer 4, a second tunneling oxide layer 8, a first silicon nitride layer 6, an N + doping layer 10, a second silicon nitride layer 11, a silver electrode 13, and a third tunneling oxide layer 9 embedded in the back surface of a portion of the N-type silicon wafer 1.
Wherein the resistivity of the N-type silicon wafer 1 is 0.5-15 omega cm, and the thickness is 50-300 um. All tunneling oxide layers are made of SiO 21 to 3nm in thickness and SiO2The growth method of (2) is a high-temperature thermal oxidation method, a nitric acid oxidation method, an ozone oxidation method or a CVD deposition method; heavily doped p + poly Si (p + doped layer 4) and n + poly Si (n + doped layer 10) by plate-type or tubular PECVD in-situ doping, boron source BH3The flow rate is 100-1000 sccm, and the pH of the phosphorus source3The flow rate is 100-1000 sccm; the thickness of the poly Si is 40-300 nm.
In this embodiment, the passivation anti-reflection layer 2 on the front surface of the silicon wafer is Al2O3Dielectric layer of SiNx, SiOxNy, SiOx, AlO2The dielectric film has a thickness of 2-15 nm, SiNx thickness of 1-80 nm, SiOxNy thickness of 1-80 nm, and SiOx thickness of 1-50 nm. Depositing a layer of Al with the thickness of 2-15 nm on the front surface of the N-type crystal silicon substrate2O3Dielectric film, second in Al2O3And depositing the SiNx/SiOxNy/SiOx dielectric film on the dielectric film by using PECVD equipment, wherein the SiNx/SiOxNy/SiOx dielectric film is a single-layer dielectric film or a multi-layer dielectric film, and the deposition is not performed in sequence.
The structure of the back surface of the N-type silicon wafer 1 in this embodiment is specifically as follows:
the back surface of the N-type silicon wafer 1 is sequentially covered with a first tunneling oxide layer 3 and a p + doping layer 4, the thickness of the first tunneling oxide layer 3 is 2nm, the thickness of the p + doping layer 4 is 100nm, a first notch 5 is formed in the first tunneling oxide layer 3 and the p + doping layer 4 locally, a first silicon nitride layer 6 covers on one side, away from the first tunneling oxide layer 3, of the p + doping layer 4 and on the side, close to the first notch 5, of the first tunneling oxide layer 3 and the side, close to the first notch 5, of the p + doping layer 4, and the preferable thickness is 80 nm.
The first silicon nitride layer 6 covering the p + doped layer 4 far from the first tunneling oxide layer 3 is provided with a second groove 7, and the second groove 7 is internally provided with a second tunneling oxide layer 8, preferably with the thickness of 2 nm.
An N + doped layer 10 is arranged between the adjacent first silicon nitride layers 6 in the first grooves 5 and in the second grooves 7, the thickness is preferably 100nm, and a third tunneling oxide layer 9 is arranged on the back surface of the N-type silicon wafer 1 in a region corresponding to the N + doped layer 10, and the thickness is preferably 2 nm. The n + doped layer 10 in the first trench 5 and the n + doped layer 10 in the second trench 7 extend outwards to the same height, and a second silicon nitride layer 11, preferably 150nm thick, is provided on the n + doped layer 10, and silver electrodes 13 are provided corresponding to the second silicon nitride layer 11, all silver electrodes 13 also being located at the same height. A third trench 12 is present between the n + doped layer 10 corresponding to the first trench 5 and the n + doped layer 10 corresponding to the second trench 7.
That is, the cell in this example comprises an N-type crystalline silicon substrate, Al on the front surface of the N-type silicon substrate2O3The double-layer or multi-layer passivation antireflection film of SiNx, SiOxNy, SiOx and the like sequentially comprises back contact tunnel junctions (-SiO) which are arranged in a cross way from inside to outside on the back surface of an N-type silicon substrate2-p+poly Si-SiO2-n + poly Si) and back contact-n + poly Si, a back passivation film, and a metallic silver electrode 13.
The front surface of the N-TBC back contact structure crystalline silicon solar cell of the embodiment is not shielded by any metal grid line, and is not compounded by any doping, so that the current density and the open-circuit voltage of the cell can be well improved; the back adopts the structure of passivation contact, and the metal puncture of reduction silver that can be fine reduces the metal complex of battery, improves the open circuit voltage of battery, when improving battery efficiency, has practiced thrift the cost of battery.
EXAMPLE 2 preparation of N-TBC Back contact solar cell
The embodiment provides a method for preparing an N-TBC back contact solar cell based on embodiment 1, which specifically includes the following steps:
(1) sequentially carrying out damage removal, texturing, cleaning and back polishing treatment on the N-type silicon wafer 1
Selecting an N-type silicon substrate, removing a mechanical damage layer and oil stains by using an alkaline solution, and then carrying out conventional texturing and cleaning; the N-type silicon back surface is then subjected to a hot alkali polishing process as shown in fig. 1.
The resistivity of the N-type crystalline silicon substrate selected in this example was 6 Ω · cm, and the thickness was 180 um.
(2) Preparing a first tunneling oxide layer 3 and a p + doped layer 4
As shown in fig. 2, a first tunneling oxide layer 3 and a heavily doped p + doped layer 4(p + poly Si) are grown on the back surface of the N-type crystalline silicon substrate processed in the step (1), and high-temperature annealing is performed, wherein the peak temperature of annealing is 1000 ℃, the annealing time is 100min, and the ambient atmosphere is N2And O2。
The thickness of the first tunnel oxide layer 3 is 2 nm. Heavily doped p + doped layer 4 is doped in situ by plate-type or tubular PECVD (plasma enhanced chemical vapor deposition), and boron source BH3The flow rate is 800 sccm; the p + doped layer 4 is 100nm thick.
(3) First laser opening
As shown in fig. 3, the back surface of the N-type crystalline silicon substrate processed in step (2) is subjected to a film opening process by using laser, and a first trench 5 is partially opened on the first tunneling oxide layer 3 and the p + doped layer 4, and is cleaned. The laser wavelength used was 532 nm.
(4) Depositing a first silicon nitride layer 6
And (4) depositing a silicon nitride film of 80nm, namely a first silicon nitride layer 6, on the back surface of the N-type crystal silicon substrate treated in the step (3).
The first silicon nitride layer 6 covers the side of the p + doped layer 4 far from the first tunnel oxide layer 3 and the side surfaces of the first tunnel oxide layer 3 and the p + doped layer 4 close to the first trench 5, as shown in fig. 4.
(5) Second laser opening
As shown in fig. 5, the back surface of the N-type crystalline silicon substrate processed in step (4) is subjected to a film opening process by a laser, and a second trench 7 is opened in the first silicon nitride layer 6 and cleaned. The laser wavelength used was 532 nm.
(6) Preparing a second tunneling oxide layer 8, a third tunneling oxide layer 9 and an n + doped layer 10
As shown in fig. 6, a second tunnel oxide layer 8 is grown in the second trench 7. And because the first laser film opening causes damage to the back of the N-type silicon wafer 1, the second tunneling oxide layer 8 grows while the third tunneling oxide layer 9 grows on the back of the N-type silicon wafer 1 corresponding to the first open groove 5, the damage to the back of the N-type silicon wafer 1 caused by the first laser film opening can be repaired, and the quality and the power generation efficiency of the silicon wafer are improved.
Growing heavily doped N + poly Si to form an N + doped layer 10, and performing high-temperature annealing treatment, wherein the annealing peak temperature is 700-900 ℃, the annealing time is 30-200 min, and the environment atmosphere is N2And O2. An n + doped layer 10 covers the surface of the first silicon nitride layer 6 and fills the first trench 5 and the second trench 7.
The thickness of the second tunnel oxide layer 8 and the third tunnel oxide layer 9 is 2 nm. Heavily doped n + doped layer 10 is doped in situ by plate or tubular PECVD, phosphorus source PH3The flow rate is 800 sccm; the thickness of the n + doped layer 10 is 100 nm.
The first tunneling oxide layer 3, the second tunneling oxide layer 8 and the third tunneling oxide layer 9 are all made of SiO2Preferably 1 to 3nm in thickness and SiO2The growth method of (3) is a high-temperature thermal oxidation method, a nitric acid oxidation method, an ozone oxidation method or a CVD deposition method.
(7) Preparing a second silicon nitride layer 11
As shown in fig. 7, a silicon nitride film of 150nm is deposited on the surface of the n + doped layer 10 to form a second silicon nitride layer 11, and then cleaned.
(8) Depositing a front passivation anti-reflection film
As shown in FIG. 8, on the front surface of the N-type crystalline silicon substrate treated in the step (7), a double-layer or multi-layer passivated anti-reflection film Al is deposited2O3The number of layers and the thickness of the passivation antireflection film/SiNx/SiOxNy/SiOx can be prepared according to actual conditions.
(9) Third laser film opening
As shown in fig. 9, the back surface of the N-type crystalline silicon substrate treated in step (8) is subjected to an opening process using a laser on the N + doped layer 10 and the second silicon nitride layer 11 to form a third opening 12, and then cleaned. The laser wavelength used was 355 nm.
(10) And a printed silver electrode 13
And (4) printing a silver electrode 13 on the back surface of the N-type crystal silicon substrate processed in the step (9) corresponding to the N + poly Si region to form ohmic contact, and finishing the manufacture of the N-TBC back contact solar cell, as shown in FIG. 10.
The invention relates to a crystalline silicon solar cell with an N-TBC back contact structure, which comprises an N-type crystalline silicon substrate; the front surface of the N-type silicon substrate is Al2O3Double-layer or multi-layer passivation antireflection films such as SiNx, SiOxNy and SiOx; the back surface of the N-type silicon substrate sequentially comprises back contact tunnel junctions (-SiO) which are arranged in a cross way from inside to outside2-p+poly Si-SiO2-n + poly Si) and back contact-n + poly Si, a back passivation film, and a metallic silver electrode.
The front surface of the N-TBC back contact structure crystalline silicon solar cell is not shielded by any metal grid line, and is not compounded by any doping, so that the current density and the open-circuit voltage of the cell can be well improved; the back adopts the structure of passivation contact, and the metal puncture of silver can be fine reduced, reduces the metal complex of battery, improves the open circuit voltage of battery. The invention integrates the advantages of the traditional back contact IBC battery and the passivated contact battery structure, simplifies the process flow, improves the battery efficiency and saves the battery cost.
The above embodiments are merely illustrative of the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the content of the present invention and implement the invention, and not to limit the scope of the invention, and all equivalent changes or modifications made according to the spirit of the present invention should be covered by the scope of the present invention.
Claims (10)
1. A method for preparing a TBC back contact solar cell, comprising the steps of: growing a first tunneling oxide layer and a p + doped layer on the back of the silicon wafer subjected to texturing cleaning and polishing treatment, then performing first laser film opening and cleaning on the first tunneling oxide layer and the p + doped layer, depositing a first silicon nitride layer, performing second laser film opening and cleaning on the first silicon nitride layer, growing a second tunneling oxide layer and an n + doped layer, depositing a second silicon nitride layer and cleaning; depositing a passivation anti-reflection film on the front side of the silicon wafer; and performing third laser film opening and cleaning on the n + doped layer and the second silicon nitride layer, and printing a back electrode on the corresponding n + doped layer.
2. The method of claim 1, wherein: the first tunneling oxide layer and the second tunneling oxide layer are made of SiO2And the thickness of the first tunneling oxide layer and the second tunneling oxide layer is 1-3 nm, and the growth method of the first tunneling oxide layer and the second tunneling oxide layer is a high-temperature thermal oxidation method, a nitric acid oxidation method, an ozone oxidation method or a CVD (chemical vapor deposition) deposition method.
3. The method of claim 1, wherein: the p + doping layer is formed by adopting plate-type or tubular PECVD (plasma enhanced chemical vapor deposition) in-situ doping, and the flow of a boron source is 100-1000 sccm during doping; the thickness of the p + doped layer is 40-300 nm.
4. The method of claim 1, wherein: the n + doping layer is formed by adopting plate-type or tubular PECVD (plasma enhanced chemical vapor deposition) in-situ doping, and the flow of a phosphorus source is 100-1000 sccm during doping; the thickness of the n + doped layer is 40-300 nm.
5. The method of claim 1, wherein: a first annealing step is also arranged after the first tunneling oxide layer and the p + doped layer are grown: the annealing peak temperature is 900-1100 ℃, the annealing time is 30-200 min, and the atmosphere is N2And O2。
6. The method of claim 1, wherein: a second annealing step is also arranged after the second tunneling oxide layer and the n + doped layer are grown: the annealing peak temperature is 700-900 ℃, the annealing time is 30-200 min, and the atmosphere is N2And O2。
7. The method of claim 1, wherein: and a third tunneling oxide layer is arranged on the back surface of the silicon wafer corresponding to the position of the first laser film opening.
8. The method of claim 1, wherein: the laser wavelength of the first laser film opening and the second laser film opening is 532 nm; the laser wavelength of the third laser film opening is 355 nm.
9. The production method according to any one of claims 1 to 8, characterized in that: the silicon wafer is an N-type silicon wafer.
10. A TBC back contact solar cell prepared by the preparation method of any one of claims 1 to 9.
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| CN114792744A (en) * | 2022-05-07 | 2022-07-26 | 通威太阳能(眉山)有限公司 | Solar cell and preparation method and application thereof |
| CN115985974A (en) * | 2023-01-04 | 2023-04-18 | 隆基绿能科技股份有限公司 | Back contact solar cell, preparation method thereof and photovoltaic module |
| CN116344632A (en) * | 2023-02-17 | 2023-06-27 | 扬州大学 | POLO-IBC passivation contact battery and preparation method thereof |
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| WO2016068711A2 (en) * | 2014-10-31 | 2016-05-06 | Technische Universiteit Delft | Back side contacted wafer-based solar cells with in-situ doped crystallized silicon oxide regions |
| WO2020180244A1 (en) * | 2019-03-01 | 2020-09-10 | National University Of Singapore | Solar cell and method for fabricating a solar cell |
| CN113611755A (en) * | 2021-08-06 | 2021-11-05 | 无锡琨圣智能装备股份有限公司 | Local passivation contact IBC battery structure and preparation method thereof |
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| WO2016068711A2 (en) * | 2014-10-31 | 2016-05-06 | Technische Universiteit Delft | Back side contacted wafer-based solar cells with in-situ doped crystallized silicon oxide regions |
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