CN116632073A - Back contact solar cell, preparation method thereof and photovoltaic module - Google Patents

Back contact solar cell, preparation method thereof and photovoltaic module Download PDF

Info

Publication number
CN116632073A
CN116632073A CN202310540294.6A CN202310540294A CN116632073A CN 116632073 A CN116632073 A CN 116632073A CN 202310540294 A CN202310540294 A CN 202310540294A CN 116632073 A CN116632073 A CN 116632073A
Authority
CN
China
Prior art keywords
layer
transmission layer
silicon substrate
solar cell
contact solar
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.)
Pending
Application number
CN202310540294.6A
Other languages
Chinese (zh)
Inventor
邱浩然
曹玉甲
方亮
吴华
徐希翔
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Longi Green Energy Technology Co Ltd
Original Assignee
Longi Green Energy Technology Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Longi Green Energy Technology Co Ltd filed Critical Longi Green Energy Technology Co Ltd
Priority to CN202310540294.6A priority Critical patent/CN116632073A/en
Publication of CN116632073A publication Critical patent/CN116632073A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02—Details
    • H01L31/0216—Coatings
    • H01L31/02161—Coatings for devices characterised by at least one potential jump barrier or surface barrier
    • H01L31/02167—Coatings for devices characterised by at least one potential jump barrier or surface barrier for solar cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/0248—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 at least one potential-jump barrier or surface barrier
    • H01L31/072—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 at least one potential-jump barrier or surface barrier the potential barriers being only of the PN heterojunction type
    • H01L31/0745—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 at least one potential-jump barrier or surface barrier the potential barriers being only of the PN heterojunction type comprising a AIVBIV heterojunction, e.g. Si/Ge, SiGe/Si or Si/SiC 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
    • H01L31/1804—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 System
    • 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
    • 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)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Power Engineering (AREA)
  • Sustainable Energy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Sustainable Development (AREA)
  • Photovoltaic Devices (AREA)

Abstract

The application provides a back contact solar cell, a preparation method thereof and a photovoltaic module, and relates to the technical field of photovoltaics. The back contact solar cell includes: a silicon substrate, a first transmission layer and a second transmission layer; the backlight side of the silicon substrate includes: a first conductive region and a second conductive region; the first transmission layer and the second transmission layer both comprise a back passivation layer; the material of the back passivation layer is selected from: at least one of amorphous silicon, nanocrystalline silicon, microcrystalline silicon; the first transmission layer has a first portion located on the first conductive region; the second transmission layer has a second portion on the second conductive region, and a third portion on the first portion; the second conductive region and the first portion are irradiated with the laser light. In the application, the laser with light spots not overlapped is adopted to open the film of the second transmission layer, the influence of the instantaneous high temperature of the laser film opening on the back passivation layer in the first part is small, the passivation performance of the back passivation layer is protected, and the carrier recombination at the interface is reduced.

Description

Back contact solar cell, preparation method thereof and photovoltaic module
Technical Field
The application relates to the technical field of photovoltaics, in particular to a back contact solar cell, a preparation method thereof and a photovoltaic module.
Background
The back contact solar cell has the advantages that the electrode is arranged on the back surface of the cell, so that the short-circuit current loss can be effectively reduced, and the back contact solar cell has a wide application prospect.
The amorphous silicon, the nanocrystalline silicon and the microcrystalline silicon are used as passivation layers, so that carrier recombination at an interface can be reduced, and the back contact solar cell has higher open-circuit voltage.
However, there are still more carrier recombination at the interface in the existing back contact solar cell, which reduces the open circuit voltage of the back contact solar cell.
Disclosure of Invention
The application provides a back contact solar cell, a preparation method thereof and a photovoltaic module, and aims to solve the problem that carriers are compounded at more interfaces in the existing back contact solar cell although amorphous silicon, nanocrystalline silicon and microcrystalline silicon are adopted as passivation layers.
In a first aspect of the present application, there is provided a back contact solar cell comprising: the silicon substrate is positioned on the first transmission layer, the second transmission layer, the first electrode and the second electrode on the backlight side of the silicon substrate; the backlight side of the silicon substrate includes: a first conductive region and a second conductive region;
the first transmission layer and the second transmission layer comprise a back passivation layer and a doping layer which are arranged in a stacked mode; the back passivation layer is closer to the silicon substrate than the doped layer in the first transmission layer and the second transmission layer; the doping type of the first doping layer in the first transmission layer is different from that of the second doping layer in the second transmission layer; the material of the back passivation layer is selected from the group consisting of: at least one of amorphous silicon, nanocrystalline silicon, microcrystalline silicon;
the first transmission layer has a first portion located on the first conductive region; the second transmission layer has a second portion on the second conductive region and a third portion on the first portion; the second part and the third part are distributed at intervals; the second conductive region and the first portion are irradiated by laser;
the first electrode is located in the first portion on an area other than the third portion, and the second electrode is located on the second portion.
In the embodiment of the application, the materials of the passivation layers on the back surfaces of the first transmission layer and the second transmission layer are at least one selected from amorphous silicon, nanocrystalline silicon and microcrystalline silicon, so that carrier recombination at an interface can be reduced, and the back contact solar cell has higher open circuit voltage. Meanwhile, in the back contact solar cell, the first transmission layer is provided with the first part positioned on the first conductive area, the second transmission layer is provided with the second part positioned on the second conductive area and the third part positioned on the first part, so that the preparation process of the second transmission layer is later than that of the first transmission layer, the second conductive area and the first part are irradiated by laser, the patterning of the first transmission layer and the second transmission layer is performed by means of laser, the first transmission layer is free from residues in the second conductive area, the laser spots overlap in the process of patterning the first transmission layer by laser, the back passivation layer positioned in the second conductive area in the first transmission layer is in a final cell structure, the retention and the passivation performance are not required to be protected, therefore, the laser film opening of the first transmission layer is not required to be realized, the high-temperature influence of the instant high-temperature on the back passivation layer positioned in the second conductive area in the first transmission layer is not required, the laser process window can be improved, and the yield and the production efficiency are improved. The second transmission layer is provided with a third part positioned on the first part, which indicates that laser spots are not overlapped in the process of opening the second transmission layer by laser, and the third part is left by the fact that the laser spots are not overlapped. The second part and the third part are distributed at intervals, so that short circuit in the back contact solar cell can be avoided. In summary, in the back contact solar cell, carrier recombination at the interface is less, the open-circuit voltage is higher, the laser process window is wider, and the yield and the production efficiency are higher.
Optionally, the third portion includes: a plurality of sub-portions;
all the sub-parts are communicated into a whole; or, in all the sub-parts, at least two sub-parts are communicated, and at least two sub-parts are distributed at intervals; alternatively, each of the sub-portions may be spaced apart.
Optionally, the spacing between adjacent subsections: from 20 microns to 500 microns.
Optionally, the third portion, in a total area of orthographic projection of the backlight surface of the silicon substrate, is a proportion of the total area of the backlight surface of the silicon substrate: 0.001% to 0.5%.
Optionally, the back contact solar cell further includes: an insulating layer located on a backlight side of the silicon substrate, the insulating layer comprising: a fourth portion located on the first transmission layer between the first conductive region and the second conductive region.
Optionally, the back surface of the silicon substrate is a suede structure.
Optionally, the back contact solar cell further includes: the transparent conducting layer that is located the back light side of silicon substrate, be located in proper order the front passivation layer and the front anti-reflection layer of the smooth facing surface of silicon substrate, the transparent conducting layer includes: a fifth portion located between the first electrode and the first portion, and a sixth portion located between the second electrode and the second portion; the fifth portion and the sixth portion are spaced apart.
In a second aspect of the present application, there is provided a method for manufacturing any one of the aforementioned back contact solar cells, comprising:
providing a substrate; the substrate comprises: the first transmission layer is positioned on the backlight side of the silicon substrate; the first transmission layer is arranged on the whole backlight side of the silicon substrate; the backlight side of the silicon substrate includes: a first conductive region and a second conductive region;
opening a film on the first transmission layer by adopting laser with overlapped light spots so that a second conductive area of the silicon substrate is exposed, wherein the first transmission layer is provided with a first part positioned on the first conductive area;
forming a second transmission layer on the second conductive region and the rest of the first transmission layer; the first transmission layer and the second transmission layer comprise a back passivation layer and a doping layer which are arranged in a stacked mode; the back passivation layer is closer to the silicon substrate than the doped layer in the first transmission layer and the second transmission layer; the doping type of the first doping layer in the first transmission layer is different from that of the second doping layer in the second transmission layer; the material of the back passivation layer is selected from the group consisting of: at least one of amorphous silicon, nanocrystalline silicon, microcrystalline silicon;
using laser with non-overlapping light spots to film the second transmission layer, so that the second transmission layer is provided with a second part positioned on the second conductive area and a third part positioned on the first part; the second part and the third part are distributed at intervals;
in the first portion, a first electrode is provided on an area other than the third portion, and a second electrode is provided on the second portion.
Optionally, the substrate further comprises: the whole insulating layer and the whole mask layer are sequentially arranged on the first transmission layer;
the laser with overlapped light spots is used for opening the first transmission layer, and the method comprises the following steps:
etching the mask layer by adopting laser overlapped by light spots to expose part of the insulating layer;
under the protection of the mask layer, wet etching the exposed part of the insulating layer to expose the part of the first transmission layer;
wet etching the exposed part of the first transmission layer, wherein the second conductive area of the silicon substrate is exposed;
the method further comprises the steps of: and etching the rest mask layer by adopting laser with overlapped light spots.
Optionally, after the second transmission layer is opened by using laser with non-overlapping light spots, the method further includes:
and pickling the exposed part of the insulating layer to expose the part of the first transmission layer.
In a third aspect of the present application, there is provided a photovoltaic module comprising: a number of the back contact solar cells of any of the preceding claims.
The preparation methods of the photovoltaic module and the back contact solar cell have the same or similar beneficial effects as the back contact solar cell, and in order to avoid repetition, the description is omitted here.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments of the present application will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 shows a schematic structure of a back contact solar cell according to an embodiment of the present application;
fig. 2 to 5 show schematic top view structures of four third portions in the embodiment of the present application;
FIG. 6 is a flow chart showing a method for fabricating a back contact solar cell in accordance with an embodiment of the present application;
fig. 7 to 11 are schematic views showing the structure of a manufacturing step of a back contact solar cell in an embodiment of the present application.
Description of the drawings:
1-silicon substrate, 2-back passivation layer, 3-first doped layer, 4-second doped layer, 41-third part, 411-subsection, 5-first electrode, 6-second electrode, 7-insulating layer, 8-transparent conductive layer, 9-front passivation layer, 10-front anti-reflection layer, 11-mask layer.
Detailed Description
The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
Fig. 1 shows a schematic structure of a back contact solar cell according to an embodiment of the present application. Referring to fig. 1, the back contact solar cell includes: the doping type of the silicon substrate 1 is not particularly limited to the silicon substrate 1. For example, the silicon substrate 1 may be an N-type doped silicon substrate, or may be a P-type doped silicon substrate. In the embodiment of the present application, this is not particularly limited. The silicon substrate 1 includes a light-facing surface and a backlight surface, which are relatively distributed. The backlight surface of the silicon substrate 1 refers to the surface of the silicon substrate 1 close to the electrode in the back contact solar cell. The type of the back contact solar cell may be a back contact heterojunction cell (Hetero-Junction Back Contact, HBC) or the like, and is not particularly limited.
The backlight surface of the silicon substrate 1 comprises a first conductive area and a second conductive area, in the back contact solar cell, the parts of the front projection of the backlight surface of the silicon substrate 1 falling into the first conductive area are used for separating and transmitting first carriers, and the parts of the front projection of the backlight surface of the silicon substrate 1 falling into the second conductive area are used for separating and transmitting second carriers, wherein the types of the first carriers and the second carriers are different, namely one is a hole, and the other is an electron. In the back contact solar cell, the area of the conductive region in the emitter is larger than that of the conductive region in the back field, so that the power generation efficiency of the back contact solar cell is improved. Specifically, the emitter is mainly used for separating and transmitting minority carriers, and the area of the conductive area is large, so that the emitter is larger, collection of minority carriers is facilitated, and the like, and therefore the power generation efficiency of the back contact solar cell is improved.
Referring to fig. 1, a region between the broken line L1 and the broken line L2 in the backlight surface of the silicon substrate 1 is a first conductive region, and a region between the broken line L3 and the broken line L4 in the backlight surface of the silicon substrate 1 is a second conductive region. Note that the broken lines L1, L2, L3, and L4 in fig. 1 are only schematic for illustrating the first conductive region and the second conductive region, and are not actually present in the back contact solar cell.
Referring to fig. 1, the back contact solar cell further includes: a first transmission layer and a second transmission layer positioned on the backlight side of the silicon substrate 1. The first transport layer and the second transport layer are alternately arranged. The first transfer layer includes a back passivation layer 2 and a first doped layer 3 which are stacked, the back passivation layer 2 being closer to the silicon substrate 1 than the first doped layer 3. The second transport layer comprises a back passivation layer 2 and a second doped layer 4, the back passivation layer 2 being closer to the silicon substrate 1 than the second doped layer 4. The doping types of the second doped layer 4 and the first doped layer 3 are opposite, namely, one is a P-type doped layer and the other is an N-type doped layer. The material of the back passivation layer 2 can be at least one of amorphous silicon, microcrystalline silicon and nanocrystalline silicon, and the back passivation layer 2 of the material can reduce carrier recombination at an interface, so that the back contact solar cell has higher open circuit voltage. For example, the back passivation layer 2 may be at least one of intrinsic amorphous silicon, intrinsic microcrystalline silicon, and intrinsic nanocrystalline silicon, and for another example, the back passivation layer 2 may be at least one of intrinsic hydrogenated amorphous silicon, intrinsic hydrogenated microcrystalline silicon, and intrinsic hydrogenated nanocrystalline silicon. The materials of the first doped layer 3 and the second doped layer 4 may be doped polysilicon or the like. Referring to fig. 1, the first transmission layer has a first portion located on the first conductive region. It should be noted that whether the material and thickness of the back passivation layer 2 in the first transmission layer and the back passivation layer 2 in the second transmission layer are the same is not particularly limited.
The inventors found that in the conventional back contact solar cell, although amorphous silicon, nanocrystalline silicon, and microcrystalline silicon are used as passivation layers, there are still many problems of carrier recombination at the interface, which is mainly caused by: in the back contact solar cell, in the process of patterning by adopting laser etching, the passivation layer is not high-temperature resistant, and in the laser etching process, the passivation layer is greatly damaged by the instantaneous high temperature of the laser.
In response to this problem, in the present application, the second transmission layer has a second portion located on the second conductive region, and a third portion located on the first portion, the second portion and the third portion being spaced apart. As shown with reference to fig. 1, the portion of the first transport layer located between the dashed lines L1 and L2 is the first portion. The portion of the second transport layer located between the dashed lines L3 and L4 is the second portion. The portion of the second transmission layer located on the first portion is the third portion. The second conductive area and the first part are irradiated by laser, the patterning of the first transmission layer and the second transmission layer is performed by means of the laser, the preparation process of the second transmission layer is later than that of the first transmission layer, the first transmission layer does not remain in the second conductive area, the laser spots overlap in the process of patterning the first transmission layer by the laser, the back passivation layer 2 positioned in the second conductive area in the first transmission layer is not required to be reserved in a final battery structure, and passivation performance of the back passivation layer 2 is not required to be protected, therefore, laser film opening of the first transmission layer is not required to be considered, high-temperature influence of instantaneous high temperature on the back passivation layer 2 positioned in the second conductive area in the first transmission layer is not required, a laser process window can be improved, and the yield and the production efficiency are improved. The second transmission layer is provided with a third part positioned on the first part, which indicates that laser spots are not overlapped in the process of opening the second transmission layer by laser, and the third part is left by the fact that the laser spots are not overlapped, and because the laser spots are not overlapped, the influence of the instantaneous high temperature of the laser opening on the back passivation layer 2 in the first part is small, the passivation performance of the back passivation layer 2 in the first part is protected, carrier recombination at an interface can be reduced, and the back contact solar cell has higher open circuit voltage. The second part and the third part are distributed at intervals, so that short circuit in the back contact solar cell can be avoided. In summary, in the back contact solar cell, carrier recombination at the interface is less, the open-circuit voltage is higher, the laser process window is wider, and the yield and the production efficiency are higher.
The first electrode 5 is located in the first portion, on a region other than the third portion. The second electrode 6 is located on the second portion. The material and the like of the first electrode 5 and the second electrode 6 are not particularly limited.
Fig. 2 to 5 show schematic top view structures of four third portions in the embodiment of the present application. The schematic plan view of the third portion may be a schematic plan view of the third portion viewed from a direction away from the silicon substrate 1 toward the silicon substrate 1 on the backlight side of the third portion. Alternatively, referring to fig. 2 to 5, the third portion 41 includes: a number of sub-portions 411. The number of sub-portions 411 included in the third portion 41 is not particularly limited. For example, the third section 41 in fig. 5 includes 9 sub-sections 411. Alternatively, referring to fig. 2 and 3, all sub-portions 411 of the third portion 41 are integrally connected. Referring to fig. 4, of all the sub-portions 411, at least two sub-portions 411 are communicated, and at least two sub-portions 411 are spaced apart. Referring to fig. 5, the sub-portions 411 are all spaced apart, and the third portion 41 is flexible and versatile.
The profile of the third portion 41 matches the shape of the spot of the laser light used in etching the first transmission layer.
Alternatively, referring to fig. 4 and 5, the spacing L between adjacent sub-portions 411 is 20 to 500 microns, which is due to the non-overlapping laser spots, and the laser process is simple and easy to operate in the case where the spacing L between adjacent sub-portions 411 is 20 to 500 microns. The first subsection 411 is adjacent to the second subsection 411, where the spacing may be between one of the first subsection 411 and one of the second subsection 411 adjacent to the first subsection 411.
For example, the spacing L between adjacent subsections 411 may be 20 microns, or 30 microns, or 80 microns, or 100 microns, or 180 microns, or 300 microns, or 390 microns, or 500 microns.
Optionally, the total area of orthographic projection of the third portion 41 on the back surface of the silicon substrate 1 is as follows: from 0.001% to 0.5%, in this range, a good balance is achieved between the protection of the passivation properties of the back passivation layer 2 in the first transport layer, and the loss of electrical properties caused by this third portion 41.
For example, the ratio of the total area of orthographic projection of the third portion 41 on the back surface of the silicon substrate 1 to the total area of the back surface of the silicon substrate 1 is: 0.001%, or 0.003%, or 0.01%, or 0.04%, or 0.09%, or 0.1%, or 0.103%, or 0.221%, or 0.278%, or 0.3%, or 0.361%, or 0.41%, or 0.411%, or 0.5%.
Optionally, referring to fig. 1, the back contact solar cell further includes: an insulating layer 7 located on the backlight side of the silicon substrate 1, the insulating layer 7 including: a fourth portion located on the first transmission layer between the first conductive region and the second conductive region. That is, the insulating layer 7 includes: a fourth portion between the dashed lines L2 and L3 on the first transmission layer, the fourth portion of the insulating layer 7 serving as an electrical isolation, avoiding short circuits.
Optionally, referring to fig. 1, the insulating layer 7 further includes a portion located on the first portion of the first transmission layer, and between the third portion.
Alternatively, the material of the insulating layer 7 may be selected from: at least one of silicon nitride, silicon oxynitride, silicon oxide, and silicon carbide, the material of the insulating layer 7 is easy to obtain, and the insulating property is good.
Optionally, the backlight surface of the silicon substrate 1 has a suede structure, so that the light trapping effect can be improved.
Optionally, referring to fig. 1, the back contact solar cell further includes: the transparent conductive layer 8 located on the backlight side of the silicon substrate 1, the front passivation layer 9 and the front antireflection layer 10 located on the light facing surface of the silicon substrate 1 in sequence, the transparent conductive layer 8 includes: a fifth portion between the first electrode 5 and said first portion, and a sixth portion between the second electrode 6 and the second portion. The fifth part and the sixth part are arranged at intervals, so that the back contact solar cell is prevented from being short-circuited. The size of the interval between the fifth portion and the sixth portion is not particularly limited.
The application also provides a preparation method of any of the back contact solar cells, and fig. 6 shows a flowchart of a preparation method of the back contact solar cell in the embodiment of the application. Referring to fig. 6, the method may include the steps of:
step 101, providing a substrate; providing a substrate; the substrate comprises: the first transmission layer is positioned on the backlight side of the silicon substrate; the first transmission layer is arranged on the whole backlight side of the silicon substrate; the backlight side of the silicon substrate includes: a first conductive region and a second conductive region.
Fig. 7 to 11 are schematic views showing the structure of a manufacturing step of a back contact solar cell in an embodiment of the present application.
Referring to fig. 7, the back surface of the silicon substrate 1 may be a lower side surface. For example, the silicon substrate 1 may be an N-type silicon substrate. The backlight surface of the silicon substrate 1 may be first textured. Referring to fig. 8, a first transmission layer is formed on the entire surface of a backlight surface of a silicon substrate 1. For example, hydrogenated amorphous silicon may be deposited as the back passivation layer 2, the phosphorus doped second doped layer 3, using PECVD (Plasma Enhanced Chemical Vapor Deposition ).
Alternatively, referring to fig. 8, an entire insulating layer 7, and an entire mask layer 11 are formed on the first transfer layer. The material of the insulating layer 7 here may be at least one of silicon nitride, silicon oxide, silicon oxynitride, silicon carbide, and the like. The mask layer 11 is present as a mask for the insulating layer 7 during a subsequent wet etching process.
And 102, opening a film on the first transmission layer by adopting laser with overlapped light spots so that the second conductive area of the silicon substrate is exposed, wherein the first transmission layer is provided with a first part positioned on the first conductive area.
Referring to fig. 9, a first transmission layer having a first portion on a first conductive region is opened by laser light overlapped with a light spot so that a second conductive region of a back surface of the silicon substrate 1 is exposed. Here the spots of the laser light overlap, so that the portion of the first transmission layer located in the second conductive region can be completely removed.
Alternatively, referring to fig. 8 and 9, step 102 may be: the mask layer 11 is etched using laser light with overlapping spots so that the insulating layer 7 is partially exposed. Here, the spots of the laser light overlap, so that the portion of the mask layer 11 located in the second conductive region can be completely removed, so that the portion of the insulating layer 7 located in the first conductive region is exposed. Under the protection of the mask layer 11, the exposed part of the insulating layer 7 is wet etched, wherein the wet etching can be acid washing or alkaline, and the part of the insulating layer 7 located in the second conductive area can be thoroughly removed, so that the first transmission layer is partially exposed. The exposed part of the first transmission layer is etched by a wet method, the second conductive area of the silicon substrate 1 is exposed, and the part of the first transmission layer located in the second conductive area is thoroughly removed. For example, the exposed portion of the insulating layer 7 may be pickled so that the first transmission layer is partially exposed, and if the first doped layer 3 in the first transmission layer is N-doped, the exposed portion of the first transmission layer may be alkali-washed. The method may further comprise: and etching the residual mask layer 11 by adopting laser with overlapped light spots, so as to thoroughly remove the residual mask layer 11.
Step 103, forming a second transmission layer on the second conductive area and the rest of the first transmission layer; the first transmission layer and the second transmission layer comprise a back passivation layer and a doping layer which are arranged in a stacked mode; the back passivation layer is closer to the silicon substrate than the doped layer in the first transmission layer and the second transmission layer; the doping type of the first doping layer in the first transmission layer is different from that of the second doping layer in the second transmission layer; the material of the back passivation layer is selected from the group consisting of: at least one of amorphous silicon, nanocrystalline silicon, and microcrystalline silicon.
Referring to fig. 10, an entire second transmission layer is formed on the remaining first transmission layer and the second conductive region of the back surface of the silicon substrate 1. For example, the deposition of the backside passivation layer 2 and the deposition of the second doped layer 4 may be performed on the remaining first transport layer and the second conductive region of the backside surface of the silicon substrate 1 using PECVD. The second doped layer 4 here may be P-type doped.
Step 104, using laser with non-overlapping light spots to film the second transmission layer, so that the second transmission layer has a second part positioned on the second conductive area and a third part positioned on the first part; the second portion and the third portion are spaced apart.
Referring to fig. 11, the second transmission layer is patterned using laser light with non-overlapping spots such that the second transmission layer has a second portion on the second conductive region and a third portion on the first portion of the first transmission layer. The second portion and the third portion are spaced apart. The pitch between the laser spots is not particularly limited here.
Optionally, referring to fig. 11, the method may further include: the exposed part of the insulating layer 7 is pickled so that the first transmission layer is partially exposed, in particular the exposed part of the insulating layer 7 on the first part of the first transmission layer is pickled. The acid washing solution may be hydrofluoric acid or the like, and is not particularly limited.
Step 105, in the first portion, a first electrode is disposed on a region other than the third portion, and a second electrode is disposed on the second portion.
Referring to fig. 1, in the first portion, a first electrode 5 is provided on an area other than the third portion, and a second electrode 6 is provided on the second portion.
Optionally, referring to fig. 1, before the first electrode 5 and the second electrode 6 are provided, the method may further include: the entire transparent conductive layer 8, the front passivation layer 9 and the front anti-reflection layer 10 are formed, and then the transparent conductive layer 8 is blocked, resulting in a fifth portion located on the first portion and a sixth portion located between the second portions. For example, PECVD may be used to deposit the front passivation layer 10 and the front anti-reflection layer 10 on the entire surface of the light-facing surface of the silicon substrate 1. The deposition of the transparent conductive layer 8 is performed by PVD (Physical Vapor Deposition )/RPD (Reactive Plasma Deposition, reactive plasma deposition) or the like. The step of disposing the electrodes may be to dispose the first electrode 5 on the region other than the third portion in the fifth portion and dispose the second electrode 6 on the sixth portion. The first electrode 5 and the second electrode 6 can be prepared by silk screen printing, electroplating and the like.
The application also provides a photovoltaic module, which comprises a plurality of back contact solar cells. The photovoltaic module may further include: front packaging adhesive film and cover plate positioned on the light-facing side of the back contact solar cell, and rear packaging adhesive film and back plate positioned on the backlight side of the back contact solar cell.
The photovoltaic module and the preparation method of the back contact solar cell have the same or similar beneficial effects as any one of the back contact solar cells, and in order to avoid repetition, the description is omitted here.
It should be noted that, for simplicity of description, the method embodiments are shown as a series of acts, but it should be understood by those skilled in the art that the embodiments are not limited by the order of acts, as some steps may occur in other orders or concurrently in accordance with the embodiments. Further, those skilled in the art will appreciate that the embodiments described in the specification are presently preferred, and that the acts are not necessarily all required in accordance with the embodiments of the application.
It should be noted that, in this document, 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.
From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment method may be implemented by means of software plus a necessary general hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. ROM/RAM, magnetic disk, optical disk) comprising instructions for causing a terminal (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to perform the method according to the embodiments of the present application.
The embodiments of the present application have been described above with reference to the accompanying drawings, but the present application is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many forms may be made by those having ordinary skill in the art without departing from the spirit of the present application and the scope of the claims, which are to be protected by the present application.

Claims (11)

1. A back contact solar cell, comprising: the silicon substrate is positioned on the first transmission layer, the second transmission layer, the first electrode and the second electrode on the backlight side of the silicon substrate; the backlight side of the silicon substrate includes: a first conductive region and a second conductive region;
the first transmission layer and the second transmission layer comprise a back passivation layer and a doping layer which are arranged in a stacked mode; the back passivation layer is closer to the silicon substrate than the doped layer in the first transmission layer and the second transmission layer; the doping type of the first doping layer in the first transmission layer is different from that of the second doping layer in the second transmission layer; the material of the back passivation layer is selected from the group consisting of: at least one of amorphous silicon, nanocrystalline silicon, microcrystalline silicon;
the first transmission layer has a first portion located on the first conductive region; the second transmission layer has a second portion on the second conductive region and a third portion on the first portion; the second part and the third part are distributed at intervals; the second conductive region and the first portion are irradiated by laser;
the first electrode is located in the first portion on an area other than the third portion, and the second electrode is located on the second portion.
2. The back contact solar cell of claim 1, wherein the third portion comprises: a plurality of sub-portions;
all the sub-parts are communicated into a whole; or, in all the sub-parts, at least two sub-parts are communicated, and at least two sub-parts are distributed at intervals; alternatively, each of the sub-portions may be spaced apart.
3. The back contact solar cell of claim 1, wherein the spacing between adjacent sub-portions: from 20 microns to 500 microns.
4. The back contact solar cell of claim 1, wherein the third portion, in total area of orthographic projection of the back surface of the silicon substrate, is in proportion to the total area of the back surface of the silicon substrate: 0.001% to 0.5%.
5. The back contact solar cell of any one of claims 1 to 4, further comprising: an insulating layer located on a backlight side of the silicon substrate, the insulating layer comprising: a fourth portion located on the first transmission layer between the first conductive region and the second conductive region.
6. The back contact solar cell of any one of claims 1 to 4, wherein the back surface of the silicon substrate is textured.
7. The back contact solar cell of any one of claims 1 to 4, further comprising: the transparent conducting layer that is located the back light side of silicon substrate, be located in proper order the front passivation layer and the front anti-reflection layer of the smooth facing surface of silicon substrate, the transparent conducting layer includes: a fifth portion located between the first electrode and the first portion, and a sixth portion located between the second electrode and the second portion; the fifth portion and the sixth portion are spaced apart.
8. A method of manufacturing a back contact solar cell according to any one of claims 1 to 7, comprising:
providing a substrate; the substrate comprises: the first transmission layer is positioned on the backlight side of the silicon substrate; the first transmission layer is arranged on the whole backlight side of the silicon substrate; the backlight side of the silicon substrate includes: a first conductive region and a second conductive region;
opening a film on the first transmission layer by adopting laser with overlapped light spots so that a second conductive area of the silicon substrate is exposed, wherein the first transmission layer is provided with a first part positioned on the first conductive area;
forming a second transmission layer on the second conductive region and the rest of the first transmission layer; the first transmission layer and the second transmission layer comprise a back passivation layer and a doping layer which are arranged in a stacked mode; the back passivation layer is closer to the silicon substrate than the doped layer in the first transmission layer and the second transmission layer; the doping type of the first doping layer in the first transmission layer is different from that of the second doping layer in the second transmission layer; the material of the back passivation layer is selected from the group consisting of: at least one of amorphous silicon, nanocrystalline silicon, microcrystalline silicon;
using laser with non-overlapping light spots to film the second transmission layer, so that the second transmission layer is provided with a second part positioned on the second conductive area and a third part positioned on the first part; the second part and the third part are distributed at intervals;
in the first portion, a first electrode is provided on an area other than the third portion, and a second electrode is provided on the second portion.
9. The method of manufacturing a back contact solar cell of claim 8, wherein the substrate further comprises: the whole insulating layer and the whole mask layer are sequentially arranged on the first transmission layer;
the laser with overlapped light spots is used for opening the first transmission layer, and the method comprises the following steps:
etching the mask layer by adopting laser overlapped by light spots to expose part of the insulating layer;
under the protection of the mask layer, wet etching the exposed part of the insulating layer to expose the part of the first transmission layer;
wet etching the exposed part of the first transmission layer, wherein the second conductive area of the silicon substrate is exposed;
the method further comprises the steps of: and etching the rest mask layer by adopting laser with overlapped light spots.
10. The method for manufacturing a back contact solar cell according to claim 9, wherein after the second transmission layer is laminated by using laser light with non-overlapping spots, the method further comprises:
and pickling the exposed part of the insulating layer to expose the part of the first transmission layer.
11. A photovoltaic module comprising a plurality of back contact solar cells according to any one of claims 1 to 7.
CN202310540294.6A 2023-05-12 2023-05-12 Back contact solar cell, preparation method thereof and photovoltaic module Pending CN116632073A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310540294.6A CN116632073A (en) 2023-05-12 2023-05-12 Back contact solar cell, preparation method thereof and photovoltaic module

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310540294.6A CN116632073A (en) 2023-05-12 2023-05-12 Back contact solar cell, preparation method thereof and photovoltaic module

Publications (1)

Publication Number Publication Date
CN116632073A true CN116632073A (en) 2023-08-22

Family

ID=87635777

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310540294.6A Pending CN116632073A (en) 2023-05-12 2023-05-12 Back contact solar cell, preparation method thereof and photovoltaic module

Country Status (1)

Country Link
CN (1) CN116632073A (en)

Similar Documents

Publication Publication Date Title
US20180233621A1 (en) Solar cell and method for manufacturing the same
JP3349308B2 (en) Photovoltaic element
EP3349253B1 (en) Semiconductor devices and methods for manufacturing the same
EP3496158A1 (en) Solar cell and method of manufacturing the same
JP2013513964A (en) Back contact / heterojunction solar cell
NL2034302B1 (en) Solar cell and photovoltaic module
US11251325B2 (en) Photovoltaic device and method for manufacturing the same
US9997647B2 (en) Solar cells and manufacturing method thereof
CN111987184A (en) Laminated battery structure and preparation process thereof
CN116632074A (en) Back contact solar cell, preparation method thereof and photovoltaic module
KR101714779B1 (en) Solar cell and manufacturing method thereof
EP2584610A2 (en) Photoelectric device
KR20150090607A (en) Solar cell and manufacturing method thereof
CN216597603U (en) Back contact heterojunction solar cell capable of improving insulation and isolation effects
JP4169463B2 (en) Photovoltaic element manufacturing method
CN114038922A (en) Back contact heterojunction solar cell capable of improving insulation and isolation effects and manufacturing method thereof
CN116632073A (en) Back contact solar cell, preparation method thereof and photovoltaic module
KR20180127597A (en) Back contact silicon solar cell and method for manufacturing the same
CN112054094A (en) Solar cell and manufacturing method thereof
CN218957742U (en) Back contact solar cell and photovoltaic module
CN219937063U (en) Edge etched full-area TCO covered heterojunction solar cell
JP2014056875A (en) Photoelectric conversion element and photoelectric conversion element manufacturing method
WO2024098920A1 (en) Back contact solar cell, manufacturing method therefor, and photovoltaic module
CN117558766A (en) Back contact solar cell, preparation method thereof and photovoltaic module
KR100374810B1 (en) Preparation method of buried contact 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