CN117410382A - Electrode metallization method of solar cell, assembly and system - Google Patents

Electrode metallization method of solar cell, assembly and system Download PDF

Info

Publication number
CN117410382A
CN117410382A CN202311536400.XA CN202311536400A CN117410382A CN 117410382 A CN117410382 A CN 117410382A CN 202311536400 A CN202311536400 A CN 202311536400A CN 117410382 A CN117410382 A CN 117410382A
Authority
CN
China
Prior art keywords
metal material
layer
material layer
doped region
dielectric layer
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
CN202311536400.XA
Other languages
Chinese (zh)
Inventor
宋鹏
蒙勇
武禄
殷实
杨苗
曲铭浩
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 CN202311536400.XA priority Critical patent/CN117410382A/en
Publication of CN117410382A publication Critical patent/CN117410382A/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
    • H01L31/18—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
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
    • H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
    • H01L21/321—After treatment
    • H01L21/3213—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02—Details
    • H01L31/0224—Electrodes
    • H01L31/022408—Electrodes for devices characterised by at least one potential jump barrier or surface barrier
    • H01L31/022425—Electrodes for devices characterised by at least one potential jump barrier or surface barrier for solar cells
    • H01L31/022441—Electrode arrangements specially adapted for back-contact 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
    • H01L31/20—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof such devices or parts thereof comprising amorphous semiconductor materials
    • H01L31/202—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof such devices or parts thereof comprising amorphous semiconductor materials including only elements of Group IV of the Periodic System

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Electromagnetism (AREA)
  • Manufacturing & Machinery (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Photovoltaic Devices (AREA)

Abstract

The application discloses an electrode metallization method of a solar cell, the solar cell, a component and a system. Wherein the electrode metallization method comprises the following steps: preparing a conductive metal material layer on the doped region; preparing a dielectric layer on the silicon substrate and the metal material layer; and processing the dielectric layer to expose the metal material layer to obtain the metal electrode. The electrode metallization method can ensure that the reliably exposed electrode can not damage passivation contact, has an annealing effect on the metal material layer, optimizes ohmic contact between the metal material layer and the doped region, and further improves battery efficiency.

Description

Electrode metallization method of solar cell, assembly and system
Technical Field
The invention relates to the technical field of solar cells, in particular to an electrode metallization method of a solar cell, the solar cell, a component and a system.
Background
The cell structure of the solar cell (such as TOPCON cell) comprises an ultrathin tunneling oxide layer and a doped polysilicon layer, so that the cell structure can remarkably reduce metal contact recombination, has good contact performance, and can greatly improve the efficiency of the photovoltaic cell. In the preparation process of the battery structure, the processes of silicon wafer, texturing, diffusion, SE, pre-oxidation, etching, post-oxidation, coating, laser grooving, electroplating, annealing, testing and the like are generally involved. Particularly in the preparation of the back electrode, the contact window is formed by laser etching of the anti-reflection film and partial doped polysilicon layer, and then the technological link of preparing the metal electrode by an electroplating method is involved; if the laser energy is too small, the silicon nitride film layer cannot be completely opened to leak the polysilicon layer, so that poor conductivity is caused to influence the electroplating effect, and therefore, an ideal metal electrode is difficult to prepare on the surface of the solar cell, and the contact performance of the solar cell is further influenced.
Disclosure of Invention
In view of the foregoing drawbacks or shortcomings of the prior art, it is desirable to provide a method of electrode metallization of a solar cell, and a solar cell, assembly and system, wherein a dielectric layer is prepared on a metal material layer, and the dielectric layer is treated by a laser to facilitate obtaining a metal electrode without damaging the doped region and the dielectric layer.
In a first aspect, the present invention provides a method for metallizing an electrode of a solar cell, comprising:
preparing a conductive metal material layer on the doped region;
preparing a dielectric layer on the silicon substrate and the metal material layer;
the dielectric layer is processed to expose the metal material layer to obtain a metal electrode.
Alternatively, the doped region is located in a partial region of the back surface of the silicon substrate; or the doped region is located in the whole area of the back surface of the silicon substrate.
Alternatively, the metal material layer covers the entire doped region; or a layer of metal material covers a portion of the doped region.
Alternatively, the doped region includes a first doped region and a second doped region, each of the first doped region and the second doped region being disposed corresponding to the first polarity and the second polarity, respectively.
Alternatively, the metal material layer includes a first metal material layer and a second metal material layer, where the first metal material layer and the second metal material layer correspond to the first doped region and the second doped region, respectively.
Alternatively, the doped region includes one of doped polysilicon, doped amorphous silicon, doped nanocrystalline silicon, doped SiC, doped CdS, doped ZnO, and doped CuO.
Alternatively, the dielectric layer includes an anti-reflective layer.
Alternatively, the dielectric layer further comprises a passivation layer.
Alternatively, preparing a conductive metal material layer on the doped region includes:
a layer of metal material is prepared on the doped regions by electroplating, screen printing or laser transfer.
Alternatively, preparing a dielectric layer on the silicon substrate and the metal material layer includes:
a dielectric layer is prepared on the metal material layer by a plasma enhanced chemical vapor deposition method.
Alternatively, the thickness of the dielectric layer is 1nm to 150nm, preferably 50nm to 90nm, during deposition of the dielectric layer on the metal material layer by plasma enhanced chemical vapor deposition.
Alternatively, treating the dielectric layer to expose the metal material layer includes:
eliminating the dielectric layer on the metal material layer by laser; or alternatively, the first and second heat exchangers may be,
a partial region of the dielectric layer located on the metal material layer is removed by a laser.
Alternatively, in the process of treating the dielectric layer by laser to expose the metal material layer, the conditions of the laser treatment are: the laser wavelength is 1 μm-10 μm, the pulse width is 1ps-500ns, the laser spot shape is square or round, the diameter of the laser spot is 0.5 μm-30 μm, and the output power is 1W-50W.
In a second aspect, the present invention provides a solar cell, at least one of the positive and negative electrodes of which is prepared according to the method of the first aspect.
In a third aspect, the present invention provides a solar cell module comprising a front surface material layer, a front surface encapsulation layer, a cell, a back surface encapsulation layer and a back surface material layer which are sequentially arranged from top to bottom, wherein the cell is a solar cell of the second aspect.
In a fourth aspect, the present invention provides a solar cell system comprising at least one solar cell module, the solar cell module being one of the solar cell modules of the third aspect.
According to the electrode metallization method of the solar cell, the conductive metal material layer is prepared on the doped region, the dielectric layer is prepared on the silicon substrate and the metal material layer, and the dielectric layer is processed so as to expose the metal material layer, so that the metal electrode is obtained; the doped region and the dielectric layer are isolated by the metal material layer, laser directly acts on the dielectric layer and the metal material layer, the reliable exposure of the electrode can be ensured, passivation contact can not be damaged, the size of the metal electrode can be precisely controlled by regulating and controlling the size of a light spot in the laser ablation process, and meanwhile, the metal material layer is annealed in the laser treatment process, so that ohmic contact between the metal material layer and the doped region is optimized, and further the battery efficiency is improved.
Drawings
Other features, objects and advantages of the present application will become more apparent upon reading of the detailed description of non-limiting embodiments, made with reference to the following drawings, in which:
FIG. 1 is a schematic flow chart of electrode metallization of a solar cell according to the present invention;
FIG. 2 is a schematic illustration of the structure of electrode metallization of a solar cell according to the present invention;
FIG. 3 is a schematic view of another solar cell electrode metallization structure according to the present invention;
fig. 4 is a schematic structural view of a solar cell according to the present invention.
In the drawing the view of the figure,
100. a solar cell;
10. a silicon substrate;
20. an emitter, 21, a first dielectric layer, 22, a front electrode;
30. a tunneling silicon oxide layer 31, a doped region 32, a back electrode 33, a second dielectric layer;
40. a metal material layer.
Detailed Description
The present application is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be noted that, for convenience of description, only the portions related to the invention are shown in the drawings.
It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
In the related art, electrode metallization of a solar cell is generally performed by etching a dielectric layer and a portion of a polysilicon layer by laser to form a contact window exposing the partially etched doped polysilicon layer, and then electroplating a metal material in the contact window region to obtain a metal electrode; however, the polysilicon layer of the contact window is damaged by the laser, and the laser etching depth and width are affected by the uniformity of the dielectric layer and the laser energy stability, which causes related problems such as interface conductivity and adhesion in the subsequent electroplating metallization, and reduces the conversion efficiency of the battery piece.
Based on the above-mentioned problems, embodiments of the present application provide a method for electrode metallization of a solar cell, as shown in fig. 1-3, including:
s10, preparing a conductive metal material layer on the doped region;
it is understood that the solar cell includes a silicon substrate having a doped region disposed on one side surface thereof; wherein the doped regions are different for different solar cell structures;
for TOPCO cells, for example, the positive and negative electrodes of the cell are located on the front and back sides, respectively, of a silicon substrate, the doped regions are typically referred to as phosphorus or other V-th A A group element doped polysilicon layer; of course, in some embodiments, the polysilicon layer may also be formed on phosphorus or other V-th material A Inorganic elements such as C, O are additionally doped on the basis of doping the group elements;
as another example, for a back-contact solar cell, the positive and negative electrodes of the cell are both on the back side of the silicon substrate, so the doped regions include a P-type doped region corresponding to the positive electrode and an N-type doped region corresponding to the negative electrode, the materials of the P-type doped region and the N-type doped region are different, for example, the P-type doped region may be polycrystalline silicon, amorphous silicon or nanocrystalline silicon doped with group IIIA elements such as B; the N-type doped region can be polycrystalline silicon doped with VA group elements such as P, amorphous silicon, nanocrystalline silicon, SIC, cdS, znO or CuO, etc.
Taking a TOPCON battery as an example, in some embodiments, the deposition of the tunneling silicon oxide layer and the deposition of the polysilicon layer can be sequentially carried out on the back surface of the silicon substrate in a low-pressure chemical vapor deposition furnace, the deposition of the tunneling silicon oxide layer and the deposition of the polysilicon layer can be respectively realized by the low-pressure chemical vapor deposition furnace, the silicon substrate is not required to be taken out after the deposition of the tunneling silicon oxide layer is finished, the deposition of the polysilicon layer is carried out, the operation is simple and convenient, and the process flow is saved; wherein the pre-deposition temperature is 600-850 ℃ and the deposition time is 10-100 min; the advancing deposition temperature is 700-1100 ℃, the advancing deposition time is 15-150 min, and the pressure is 100-400 Pa. And then, placing the treated silicon substrate into a phosphorus diffusion furnace, and carrying out phosphorus doping on the polysilicon layer on the back surface of the silicon substrate to form an N-type doped polysilicon layer.
The doped region is positioned in a partial region of the back surface of the silicon substrate, the metal material layer is deposited in the doped region, ohmic contact with the doped region is ensured, and the metal material layer is mainly used for forming an electrode; the metal material layer can be a metal element such as Au, pt, ti, pd, ag, cu, ni, al, an alloy thereof or a mixture synthesized by other materials; the positive electrode and the negative electrode of the solar cell may be made of the same metal material, or may be made of different metal materials, and the embodiment of the present application is not particularly limited thereto.
In some embodiments, the metal material layer is deposited on the polysilicon layer by means of electrochemical deposition.
Illustratively, a silicon substrate having a polysilicon layer is exposed to a copper salt (e.g., cuSO 4 ) In the solution, connecting a front electrode of a silicon substrate with a copper source (such as a copper rod), wherein the front electrode is used as a cathode, the copper source is used as an anode, and electroplating is carried out through electrochemical reaction to obtain a copper metal layer; the copper plating time is 15min-40min, the current is 100mA-300mA, and the plating solution temperature is 0 ℃ to 100 ℃.
In some embodiments, the doped region is located in the entire area of the back surface of the silicon substrate, and the metal material layer is deposited on a partial area of the doped region to ensure ohmic contact with the doped region, where the metal material layer is mainly used to form an electrode, and in this case, the metal material layer may be formed on the partial area of the doped region by screen printing, laser transfer printing, or the like.
Of course, in other embodiments, the doped region may also be located in a partial region of the backside of the silicon substrate.
S20, depositing a dielectric layer on the silicon substrate and the metal material layer;
it is understood that preparing the dielectric layer on the silicon substrate may be that the dielectric layer is deposited directly on the silicon substrate surface; it is of course also possible that the dielectric layer is deposited on other layers on the silicon substrate, for example, for some passivated contact cells, the silicon substrate surface is also formed with a tunnel oxide layer, in which case the preparation of the dielectric layer on the silicon substrate surface is actually the preparation of the dielectric layer on the surface of the tunnel oxide layer.
Wherein the dielectric layer has passivation and/or anti-reflection effects, and in some embodiments, the dielectric layer comprises an anti-reflection layer of SiN x ，SiC x ，TiO x Or other film layers of similar refractive index; in other embodiments, the dielectric layer includes a passivation layer, which may be, but is not limited to, siO x ，AlO x Or corresponding mixed materials or laminated materials; of course, in particular embodiments, the dielectric layer may also include both an anti-reflective layer and a passivation layer, the passivation layer and anti-reflective layer being stacked, e.g., the dielectric layer may be such that the SiO has both passivation and anti-reflective effects x N y Film layers, or layers of stacked SiO x And SiN x 。
And a dielectric layer is prepared on the silicon substrate and the metal material layer, so that the passivation and antireflection effects of the passivation battery are improved.
And S30, treating the dielectric layer to expose the metal material layer, thereby obtaining the metal electrode.
It will be appreciated that the treatment of the dielectric layer may be to eliminate the dielectric layer over the entire metal material layer, or to eliminate a portion of the area over the metal material layer, as long as exposure of the metal material layer is ensured.
In this embodiment, the metal material layer is located between the dielectric layer and the doped region, which is favorable for protecting the doped region and avoiding damaging the polysilicon layer, and the size of the exposed metal material layer can be adjusted as required to obtain the actually required metal electrode.
It will also be appreciated that the above method of metallizing electrodes may be applied to the preparation of back electrodes for solar cells, and of course, in some new solar cells, may also be applied to the preparation of front electrodes for solar cells.
The electrode metallization method solves the problems that in the prior art, a contact window formed by laser grooving is easy to damage a polycrystalline silicon layer and a passivation layer, the laser etching depth and width are influenced by uniformity of a dielectric layer and laser energy stability, interface conductivity and adhesion in subsequent electroplating metallization are caused, and the like. In the embodiment of the application, the conductive metal material layer is prepared on the doped region, the dielectric layer is prepared on the silicon substrate and the metal material layer, and the dielectric layer is processed so that the metal material layer is exposed, so that the metal electrode is obtained; the doped region and the dielectric layer are isolated by the metal material layer, laser directly acts on the dielectric layer and the metal material layer, the reliable exposure of the electrode can be ensured, passivation contact can not be damaged, the size of the metal electrode can be precisely controlled by regulating and controlling the size of a light spot in the laser ablation process, and meanwhile, the metal material layer is annealed in the laser treatment process, so that ohmic contact between the metal material layer and the polysilicon layer is optimized, and further the battery efficiency is improved.
In actual processing, the metal material layer may cover the entire doped region; or the metal material layer may also cover a part of the doped region, which is not limited in the embodiments of the present application, and is specifically determined according to the actual requirement of the electrode.
In some embodiments, the doped regions include a first doped region and a second doped region, each disposed corresponding to a first polarity and a second polarity, respectively.
It should be noted that, for the back contact battery, the doped region includes a P-type doped region corresponding to the positive electrode and an N-type doped region corresponding to the negative electrode, where materials of the P-type doped region and the N-type doped region are different, for example, the P-type doped region may be polysilicon doped with group IIIA elements such as B, amorphous silicon, or nanocrystalline silicon; the N-type doped region can be polycrystalline silicon doped with VA group elements such as P, amorphous silicon, nanocrystalline silicon, SIC, cdS, znO or CuO, etc.
Further, in some embodiments, the metal material layer includes a first metal material layer and a second metal material layer, the first metal material layer and the second metal material layer corresponding to the first doped region and the second doped region, respectively.
It is understood that one of the first and second metal material layers is used to form the positive electrode of the solar cell and the other is used to form the negative electrode of the metal material layer.
As an achievable manner, step S10, preparing a conductive metal material layer on the doped region, includes:
a layer of metal material is prepared on the doped regions by electroplating, screen printing or laser transfer.
The embodiment is simple to operate and can prepare the metal material by leaning on the doped region.
In a preferred embodiment, the conductive metal material layer is prepared on the doped region by electroplating, so that the operation is simple and the preparation cost is low.
As an achievable manner, step S10, electroplating and depositing a conductive metal material layer on the doped region, includes:
and placing the silicon substrate with the polysilicon layer into a salt solution containing metal of the metal electrode, selecting a metal source which is the same as the metal of the metal electrode as a counter electrode, and electroplating through oxidation-reduction reaction to obtain the metal material layer.
In the embodiment, the metal material layer is electroplated in an electrochemical oxidation-reduction mode, so that the efficiency is high, the metal material layer can be formed by leaning against the polycrystalline silicon layer, and further the preparation of the metal electrode is facilitated.
As an achievable manner, step S20, preparing a dielectric layer on the silicon substrate and the metal material layer, includes:
a dielectric layer is deposited on the metal material layer by Plasma Enhanced Chemical Vapor Deposition (PECVD).
The plasma enhanced chemical vapor deposition method in the embodiment has simple operation and can effectively control the thickness of the dielectric layer.
It is understood that the passivation and antireflection film layer may be deposited simultaneously by one method, or may be deposited first and then the antireflection layer, which is not specifically limited in the embodiments of the present application.
Illustratively, a single SiN is prepared x The silicon substrate structure electroplated with the metal material layer is placed in PECVD, the deposition temperature is 200-600 ℃, and the reaction gas is SiH 4 And NH 3 The total flow of the mixed gas is 100sccm-50000sccm, the volume ratio is 1:2-1:40, the power of the power supply is 1kW-20kW, and the pressure is 20Pa-400Pa.
In a preferred embodiment, the dielectric layer has a thickness of 1nm to 150nm during deposition of the dielectric layer on the metal material layer by plasma enhanced chemical vapor deposition.
The thickness of the dielectric layer in the embodiment is beneficial to ensuring passivation effect, and meanwhile, laser ablation is convenient, so that the metal electrode is prepared.
In a preferred embodiment, the thickness of the dielectric layer is 50nm-90nm.
As an achievable way, the dielectric layer is treated to expose the metal material layer, as shown in fig. 2 or 3, including:
eliminating the dielectric layer on the metal material layer by laser; or alternatively, the first and second heat exchangers may be,
a partial region of the dielectric layer located on the metal material layer is removed by a laser.
In this embodiment, the size of the metal electrode can be adjusted by adjusting the spot size of the laser according to the actual needs.
It can be understood that in this embodiment, the film structure of the laser action is a dielectric layer and a metal material layer, so that the damage of the laser action to the dielectric layer is avoided, and the laser can also anneal the metal material, which is beneficial to the ohmic contact between the metal material and the polysilicon layer, and further improves the conductivity of the battery;
in some embodiments, in step S30, during the process of treating the dielectric layer by laser to expose the metal material layer, the conditions of the laser treatment are: the laser wavelength is 1 μm-10 μm, the pulse width is 1ps-500ns, the laser spot shape is square or round, the diameter of the laser spot is 0.5 μm-30 μm, and the output power is 1W-50W.
It will be appreciated that the laser may be any wavelength band of laser light, such as visible light laser light, infrared light laser light, ultraviolet light laser light, etc., and in preferred embodiments the laser wavelength is in the range of 200nm to 1200nm.
The laser processing conditions disclosed by the embodiment are favorable for etching or ablating the dielectric layer, and the pulse width and the power of the laser have the optimal thermal effect, so that the annealing effect of the metal material layer is realized, and the ohmic contact between the metal material and the polysilicon layer is ensured; the dielectric layer on the metal material layer is removed by controlling the laser spot size and precisely controlling the shape of the laser spot, so that the shape of the metal electrode is adjusted.
Compared with the prior art, the electrode metallization method of the solar cell has the following advantages:
(1) The electroplated area in the prior art is a contact window of the doped polysilicon layer exposed after laser slotting, and the size of the electrode is greatly influenced by slotting width; in addition, the removal depth and damage of the polysilicon layer are difficult to control in the slotting process, so that the stability of the electroplating process and the performance of the electrode are influenced; the electroplating area of the embodiment of the application is a complete polycrystalline silicon area which is not influenced by laser, so that the damage of the laser to the polycrystalline silicon is avoided, the reliability of an electroplating process is improved, and the prepared electrode has more excellent performance;
(2) The film structure acted by the laser in the prior art is a dielectric layer-doped region; the film layer structure of the laser action is a dielectric layer-metal material layer, the damage (damage threshold: metal material > silicon nitride > polysilicon) to the polysilicon layer is avoided when the laser action is performed on the dielectric layer in the prior art, and meanwhile, the annealing action of the laser of the embodiment of the application to the metal is avoided; in addition, the size of the final electrode can be precisely controlled by regulating and controlling the size of the light spot in the laser ablation process, and simultaneously, heat generated in the process of exposing the electrode by the laser ablation anti-reflection layer can act on metal, thereby playing an annealing role on the electrode and optimizing the electrode performance.
In summary, in the electrode metallization method according to the embodiment of the present application, a conductive metal material layer is prepared on the doped region, a dielectric layer is prepared on the silicon substrate and the metal material layer, and the dielectric layer is treated by laser to expose the metal material layer, so as to obtain a metal electrode; the doped region and the dielectric layer are isolated by the metal material layer, laser directly acts on the dielectric layer and the metal material layer, so that the electrode can be reliably exposed and passivation contact can not be damaged, the size of the metal electrode can be accurately controlled by regulating and controlling the size of a light spot in the laser ablation process, and meanwhile, the metal material layer is annealed in the laser treatment process, so that ohmic contact between the metal material layer and the doped region is optimized, and further the battery efficiency is improved;
and by adjusting the laser treatment conditions, the annealing effect of the metal material layer is favorably adjusted, and good ohmic contact between the metal material layer and the polysilicon layer is further ensured.
In a second aspect, embodiments of the present application provide a solar cell 100, at least one of the positive electrode and the negative electrode of which is obtained by the manufacturing method of the first aspect.
In some embodiments, the negative and positive electrodes of the solar cell 100 correspond to the back and front electrodes, respectively, one of which is prepared by the method of the first aspect and the other of which is prepared by screen printing;
in some solar cell structures, the back electrode is prepared by the method of the first aspect, and the front electrode is prepared by screen printing; of course, in some novel solar cell structures, the front electrode is prepared by the method of the first aspect and the back electrode is prepared by screen printing.
As illustrated in fig. 4, the solar cell 100 includes a silicon substrate 10, the silicon substrate 10 having a front surface and a back surface, the front surface being sequentially laminated with an emitter electrode 20, a first dielectric layer 21, and a front electrode 22, the front electrode 22 being in ohmic contact with the emitter electrode 20 and exposed to the first dielectric layer 21;
the tunnel silicon oxide layer 30, the doped region 31 (polysilicon layer), the back electrode 32, and the second dielectric layer 33 are stacked in this order on the back surface, and the back electrode 32 is in ohmic contact with the polysilicon layer 31 and is exposed to the second dielectric layer 33.
It is understood that the silicon substrate of the solar cell may be an N-type silicon substrate; the first dielectric layer 21 and the second dielectric layer 33 mainly play a role in protecting and reducing metal recombination, and specific types of the first dielectric layer 21 and the second dielectric layer 33 are not limited, and can be selected by a person skilled in the art according to actual needs, for example, the first dielectric layer 21 and the second dielectric layer 33 can be silicon nitride layers or a mixture layer of other metal oxides and silicon nitride layers respectively;
the back surface can be a smooth surface structure, and a silicon oxide layer and a phosphorus doped polysilicon layer are deposited on the back surface, so that the passivation effect of the back surface is good, and the back electrode is not directly contacted with the silicon substrate, so that metal recombination is effectively reduced, and the open-circuit voltage of the battery is further improved; the front surface can be of a suede structure, which is beneficial to increasing the contact area of a front electrode and a silicon substrate, improving the contact resistance and reducing the surface recombination; wherein the front pile structure may be a pyramidal pile structure. In addition, the back electrode 32 may be a copper electrode, and the front electrode 22 may be a conventional metal electrode, such as a silver metal gate line electrode and an aluminum metal gate line electrode.
In a preferred embodiment, the solar cell may be an N-type double sided TOPCon cell, the silicon substrate is N-type crystalline silicon, the emitter 20 is a doped p+ emitter, and the first dielectric layer 21 is SiN x An antireflection film and an aluminum oxide passivation film, i.e., a first dielectric layer 21 including AlO sequentially disposed on the emitter electrode 20 x Film and SiN x A membrane; the back polysilicon layer is a phosphorus doped polysilicon layer and the second dielectric layer 33 is a silicon nitride film.
In summary, in the solar cell of the embodiment of the application, the back electrode and the polysilicon layer have good ohmic contact, and the passivation effect is good, so that metal recombination is reduced, and further the cell has higher cell efficiency.
In a third aspect, embodiments of the present application provide a solar cell module, including a front surface material layer, a front surface encapsulation layer, a cell, a back surface encapsulation layer, and a back surface material layer sequentially disposed from top to bottom, where the cell is a solar cell of the second aspect. It will be appreciated that the solar cell module has all the features and advantages of the solar cell described above, and will not be described in detail herein, and generally the solar cell module has high cell efficiency.
In a fourth aspect, embodiments of the present application provide a solar cell system comprising at least one solar cell module, the solar cell module being a solar cell module of the third aspect. It will be appreciated that the solar cell system has all the features and advantages of the solar cell described above, and will not be described again, and in general, the solar cell system has a high cell efficiency.
It is to be understood that the above references to the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., are for convenience in describing the present invention and simplifying the description only, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more.
The foregoing description is only of the preferred embodiments of the present application and is presented as a description of the principles of the technology being utilized. It will be appreciated by persons skilled in the art that the scope of the invention referred to in this application is not limited to the specific combinations of features described above, but it is intended to cover other embodiments in which any combination of features described above or equivalents thereof is possible without departing from the spirit of the invention. Such as the above-described features and technical features having similar functions (but not limited to) disclosed in the present application are replaced with each other.

Claims (16)

1. A method of electrode metallization of a solar cell, comprising:
preparing a conductive metal material layer on the doped region;
preparing a dielectric layer on the silicon substrate and the metal material layer;
and processing the dielectric layer to expose the metal material layer to obtain the metal electrode.
2. The method of claim 1, wherein the doped region is located in a partial region of the back surface of the silicon substrate; or the doped region is positioned in the whole area of the back surface of the silicon substrate.
3. The method of claim 1, wherein the layer of metal material covers the entire doped region; or the metal material layer covers part of the doped region.
4. The method of claim 1, wherein the doped region comprises a first doped region and a second doped region, the first doped region and the second doped region each being disposed corresponding to a first polarity and a second polarity, respectively.
5. The method of claim 4, wherein the metal material layer comprises a first metal material layer and a second metal material layer, the first metal material layer and the second metal material layer corresponding to the first doped region and the second doped region, respectively.
6. The method of claim 1, wherein the doped region comprises at least one of doped polysilicon, doped amorphous silicon, doped nanocrystalline silicon, doped SiC, doped CdS, doped ZnO, and doped CuO.
7. The method of claim 1, wherein the dielectric layer comprises an anti-reflective layer.
8. The method of claim 7, wherein the dielectric layer further comprises a passivation layer.
9. The method of any one of claims 1-8, wherein preparing a layer of conductive metallic material over the doped region comprises:
a layer of metal material is prepared on the doped regions by electroplating, screen printing or laser transfer.
10. The method of any of claims 1-8, wherein the preparing a dielectric layer on the silicon substrate and the metal material layer comprises:
a dielectric layer is deposited on the metal material layer by a plasma enhanced chemical vapor deposition process.
11. Method according to claim 10, characterized in that during deposition of a dielectric layer on the metal material layer by means of plasma-enhanced chemical vapor deposition, the dielectric layer has a thickness of 1nm-150nm, preferably 50nm-90nm.
12. The method of any of claims 1-8, wherein the treating the dielectric layer to expose the layer of metallic material comprises:
removing the dielectric layer on the metal material layer by laser; or alternatively, the first and second heat exchangers may be,
a partial region of the dielectric layer located on the metal material layer is eliminated by a laser.
13. The method of claim 12, wherein during the laser treatment of the dielectric layer to expose the metal material layer, the laser treatment conditions are: the laser wavelength is 1 μm-10 μm, the pulse width is 1ps-500ns, the laser spot shape is square or round, the diameter of the laser spot is 0.5 μm-30 μm, and the output power is 1W-50W.
14. A solar cell, characterized in that at least one of the positive and negative electrodes of the solar cell is prepared according to the method of any one of claims 1-13.
15. A solar cell module comprising a front side material layer, a front side encapsulant layer, a cell, a back side encapsulant layer, and a back side material layer arranged in that order from top to bottom, wherein the cell is a solar cell according to claim 14.
16. A solar cell system comprising at least one solar cell module, wherein the solar cell module is a solar cell module according to claim 15.
CN202311536400.XA 2023-11-16 2023-11-16 Electrode metallization method of solar cell, assembly and system Pending CN117410382A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311536400.XA CN117410382A (en) 2023-11-16 2023-11-16 Electrode metallization method of solar cell, assembly and system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311536400.XA CN117410382A (en) 2023-11-16 2023-11-16 Electrode metallization method of solar cell, assembly and system

Publications (1)

Publication Number Publication Date
CN117410382A true CN117410382A (en) 2024-01-16

Family

ID=89492565

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202311536400.XA Pending CN117410382A (en) 2023-11-16 2023-11-16 Electrode metallization method of solar cell, assembly and system

Country Status (1)

Country Link
CN (1) CN117410382A (en)

Similar Documents

Publication Publication Date Title
CN115621333B (en) Back contact solar cell passivated by double-sided tunneling silicon oxide and preparation method thereof
CN116525708B (en) Front-side wide band gap doped combined passivation back contact solar cell and preparation method thereof
EP2070128A2 (en) Method of manufacturing crystalline silicon solar cells with improved surface passivation
CN108666376B (en) P-type back contact solar cell and preparation method thereof
US20120024368A1 (en) Back contacting and interconnection of two solar cells
WO2024055475A1 (en) Joint passivation back-contact battery and manufacturing method therefor
CN111755552A (en) Solar cell and manufacturing method thereof
JP2010129872A (en) Solar battery element
CN114005908A (en) Solar cell and preparation method thereof
CN115498057A (en) Combined passivation back contact solar cell and preparation method thereof based on laser diffusion
CN114050105A (en) TopCon battery preparation method
CN115176345A (en) Solar cell laminated passivation structure and preparation method thereof
CN114937706B (en) Laminated passivation film for crystalline silicon solar cell and preparation method thereof
CN109041583B (en) Solar cell element and solar cell module
CN115692516A (en) Novel TOPCON battery and manufacturing method thereof
CN117410382A (en) Electrode metallization method of solar cell, assembly and system
CN212848426U (en) Solar cell
CN105895712A (en) Crystalline silicon amorphous silicon layer-built cell and production method thereof
CN112133768A (en) Manufacturing method of back contact solar cell and back contact solar cell
CN115799364B (en) Solar cell
CN218498078U (en) Solar cell lamination passivation structure
CN104167460A (en) Manufacturing method of solar energy cell
CN117352566B (en) Hybrid heterojunction solar cell, cell assembly and preparation method
CN217606829U (en) Solar cell
CN214753784U (en) Solar cell laminated passivation structure and 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