CN-121985617-A - Preparation method of solar cell metal electrode and solar cell

CN121985617ACN 121985617 ACN121985617 ACN 121985617ACN-121985617-A

Abstract

The invention discloses a preparation method of a solar cell metal electrode and a solar cell, and relates to the technical field of solar cells. The method comprises the steps of providing a battery matrix, wherein the battery matrix comprises a deposition area, the surface of the deposition area is a silicon surface, forming Si-F bonds on the surface of the deposition area by adopting a fluorine-containing plating layer deposition solution, depositing a seed layer, and electroplating metal outside the deposition seed layer to form an electroplated metal layer to form a metal electrode. In the preparation method, under the condition that palladium is not adopted to activate the silicon surface, the surface of the battery matrix and the deposited seed layer have stronger bonding capability, and the process for preparing the metal electrode is simplified.

Inventors

HE YUYING
DUAN GUANGLIANG
JIA JIANRONG

Assignees

晶澳（扬州）太阳能科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260120

Claims (10)

1. A method for preparing a metal electrode of a solar cell, comprising the steps of: A1, providing a battery matrix, wherein the battery matrix comprises a deposition area, and the surface of the deposition area is a silicon surface; A2, forming Si-F bonds on the surface of the deposition area by adopting a fluorine-containing plating layer deposition solution, and depositing a seed layer; and A3, electroplating metal outside the deposition seed layer to form an electroplated metal layer, and forming a metal electrode.
2. The method for manufacturing a metal electrode of a solar cell according to claim 1, wherein the step A2 specifically comprises: A21, forming Si-F bonds on the surface of the deposition area by adopting a first plating layer deposition solution containing fluorine, and forming a first deposition seed layer; A22, forming a second deposition seed layer outside the first deposition seed layer through a second plating layer deposition solution which does not contain fluorine; Optionally, after step a22, before step A3, the method further includes: Step A23, annealing the formed first deposition seed layer and second deposition seed layer; optionally, the annealing treatment process conditions comprise that the treatment temperature is 200-400 ℃ and the treatment time is 30-120 min under the nitrogen atmosphere.
3. The method for preparing the metal electrode of the solar cell according to claim 1, wherein the cell substrate comprises a doped silicon layer containing doping elements, and a protective layer is further arranged on the surface of the doped silicon layer, wherein an opening is formed at the position of the protective layer corresponding to the deposition area, and the surface of the doped silicon layer is exposed at the opening; optionally, the doped silicon layer comprises a first doped silicon layer with a first conductivity type and a second doped silicon layer with a second conductivity type, wherein the first doped silicon layer and the second doped silicon layer are respectively positioned at two sides of the battery matrix or at the same side of the battery matrix; optionally, in step A1, the opening is formed by removing a portion of the protective layer corresponding to the deposition region by laser etching.
4. A method of producing a metal electrode for a solar cell according to claim 3, wherein the cell base body comprises a crystalline silicon substrate and a diffusion layer formed by diffusing a doping element into the interior of the crystalline silicon substrate, the protective layer being provided on the diffusion layer; or the battery matrix comprises a crystalline silicon substrate, a tunneling passivation layer arranged on the surface of the crystalline silicon substrate and a doped polysilicon layer arranged on the tunneling passivation layer, and the protective layer is arranged on the doped polysilicon layer; Or the battery matrix comprises a crystalline silicon substrate, a tunneling passivation layer arranged on the surface of the crystalline silicon substrate and a doped silicon-containing film layer arranged on the tunneling passivation layer, wherein the doped silicon-containing film layer comprises amorphous silicon and/or microcrystalline silicon, and the protective layer is arranged on the doped silicon-containing film layer.
5. The method of manufacturing a metal electrode for a solar cell according to claim 2, wherein the first plating layer deposition solution comprises: Nickel salt, reducing agent, fluorine-containing compound, complexing agent and stabilizer; Preferably, the mass concentration of nickel ions in the first plating layer deposition solution is 4.5 g/L-6.5 g/L; Preferably, the pH value of the first plating layer deposition solution is 5-7; preferably, the reducing agent comprises a phosphorus reducing agent or a boron reducing agent; preferably, the phosphorus reducing agent comprises sodium hypophosphite, and the boron reducing agent comprises sodium borohydride or dimethylamine borane; preferably, the fluorine-containing compound comprises ammonium fluoride or hydrofluoric acid or ammonium bifluoride.
6. The method for manufacturing a metal electrode for a solar cell according to claim 5, wherein the second plating layer deposition solution comprises: Nickel salt, reducing agent, complexing agent, stabilizer and accelerator; Preferably, the mass concentration of nickel ions in the second plating layer deposition solution is 4.5 g/L-6.5 g/L; preferably, the pH value of the second plating layer deposition solution is 4.5-5.5; preferably, the reducing agent comprises a phosphorus reducing agent or a boron reducing agent; Preferably, the phosphorus reducing agent comprises sodium hypophosphite and the boron reducing agent comprises sodium borohydride or dimethylamine borane.
7. The method for manufacturing a metal electrode for a solar cell according to claim 6, wherein, When the reducing agent of the first plating layer deposition solution is sodium hypophosphite, the mass fraction of phosphorus in the first deposition seed layer is 1% -5%, or when the reducing agent of the first plating layer deposition solution is sodium borohydride, the mass fraction of boron in the first deposition seed layer is 0.7% -2%, or when the reducing agent of the first plating layer deposition solution is dimethylamine borane, the mass fraction of boron in the first deposition seed layer is 0.8% -1.5%; Optionally, when the reducing agent of the second plating layer deposition solution is sodium hypophosphite, the mass fraction of phosphorus in the second deposition seed layer is 5% -9%, or when the reducing agent of the second plating layer deposition solution is sodium borohydride, the mass fraction of boron in the second deposition seed layer is 0.7% -2%, or when the reducing agent of the second plating layer deposition solution is dimethylamine borane, the mass fraction of boron in the second deposition seed layer is 0.8% -1.5%.
8. A solar cell, comprising: A battery substrate including a deposition region having Si-F bonds formed on a surface thereof, and A metal electrode disposed on a surface of the deposition region; The metal electrode comprises a deposited seed layer and an electroplated metal layer which are overlapped from inside to outside.
9. The solar cell of claim 8, wherein the deposited seed layer comprises a first deposited seed layer and a second deposited seed layer disposed in a stack from inside to outside, the electroplated metal layer disposed on the second deposited seed layer; optionally, the first deposition seed layer is a nickel-phosphorus alloy layer, and the second deposition seed layer is a nickel-phosphorus alloy layer; optionally, the content of phosphorus element in the first deposition seed layer is smaller than the content of phosphorus element in the second deposition seed layer; Optionally, the mass fraction of the phosphorus element in the first deposition seed layer is 1% -5%, and the mass fraction of the phosphorus element in the second deposition seed layer is 5% -9%; optionally, the first deposition seed layer is a nickel-boron alloy layer, and the second deposition seed layer is a nickel-boron alloy layer; optionally, the mass fraction of boron element in the first deposition seed layer and the second deposition seed layer is 0.7% -2%; optionally, the mass fraction of boron element in the first deposition seed layer and the second deposition seed layer is 0.8% -1.5%; optionally, the electroplated metal layer is copper or silver.
10. The solar cell according to claim 9, wherein the cell substrate comprises a doped silicon layer containing a doping element, the solar cell further comprises a protective layer arranged on the surface of the doped silicon layer, an opening is formed at a position of the protective layer corresponding to the deposition region, and the surface of the doped silicon layer is exposed at the opening; Optionally, the first deposition seed layer is located inside the opening of the protective layer, the surface of the second deposition seed layer away from the first deposition seed layer exceeds the surface of the protective layer, and the electroplated metal layer covers the second deposition seed layer and extends to cover the protective layer near the opening; optionally, the thickness of the second deposited seed layer is greater than the thickness of the first deposited seed layer; Optionally, the doped silicon layer comprises a first doped silicon layer with a first conductivity type and a second doped silicon layer with a second conductivity type, the first doped silicon layer and the second doped silicon layer are respectively located on two sides of the battery matrix or on the same side of the battery matrix, and the first conductivity type and the second conductivity type are opposite.

Description

Preparation method of solar cell metal electrode and solar cell Technical Field The invention relates to the technical field of solar cells, in particular to a preparation method of a metal electrode of a solar cell and the solar cell. Background In order to prevent metal in the metal electrode on the surface of the solar cell from diffusing into the cell body, the cell performance is affected mainly by performing an electroless plating deposition process before electroplating the metal to block the electroplated metal from diffusing into the cell body by the plating. In the current electroless deposition process, the surface of the cell body needs to be activated by palladium to form catalytically active sites for subsequent nickel layer deposition. If palladium is not used for activation, a catalytic active site cannot be formed, and the subsequent nickel layer deposition is not facilitated, but palladium is used as noble metal, the cost is high, the activation process is complex, impurities are easy to remain, the residual impurities can reduce the binding force between the subsequent nickel layer and the battery, and the current collection efficiency of the battery is affected. Disclosure of Invention In view of the above, the embodiment of the invention provides a method for preparing a metal electrode of a solar cell and a solar cell, which can form a deposition seed layer by introducing fluorine ions to activate a deposition area in a chemical plating deposition process, thereby effectively simplifying the process for preparing the metal electrode. In order to achieve the above object, according to an aspect of the embodiments of the present invention, there is provided a method for manufacturing a solar cell metal electrode, including: A preparation method of a solar cell metal electrode comprises the following steps: A1, providing a battery matrix, wherein the battery matrix comprises a deposition area, and the surface of the deposition area is a silicon surface; A2, forming Si-F bonds on the surface of the deposition area by adopting a fluorine-containing plating layer deposition solution, and depositing a seed layer; And A3, electroplating metal outside the deposition seed layer to form an electroplated metal layer, and forming a metal electrode. Optionally, step A2 specifically includes: A21, forming Si-F bonds on the surface of the deposition area by adopting a first plating layer deposition solution containing fluorine, and forming a first deposition seed layer; A22, forming a second deposition seed layer outside the first deposition seed layer through a second plating layer deposition solution which does not contain fluorine. Optionally, after step a22, before step A3, the method further comprises: and step A23, annealing the formed first deposition seed layer and second deposition seed layer. Optionally, the annealing treatment process conditions comprise the treatment temperature of 200-400 ℃ and the treatment time of 30-120 min under the nitrogen atmosphere. Optionally, the battery matrix comprises a doped silicon layer containing doping elements, a protective layer is further arranged on the surface of the doped silicon layer, an opening is formed in the position, corresponding to the deposition area, of the protective layer, and the surface of the doped silicon layer is exposed at the opening. Alternatively, the doped silicon layer comprises a first doped silicon layer with a first conductivity type and a second doped silicon layer with a second conductivity type, the first doped silicon layer and the second doped silicon layer being located on two sides of the battery substrate or on the same side of the battery substrate, respectively, the first conductivity type and the second conductivity type being opposite. Optionally, in step A1, the portion of the protective layer corresponding to the deposition region is removed by laser etching to form an opening. Alternatively, the battery base body includes a crystalline silicon substrate and a diffusion layer formed by diffusing a doping element into the interior of the crystalline silicon substrate, and the protective layer is provided on the diffusion layer. Optionally, the battery matrix includes a crystalline silicon substrate, a tunneling passivation layer disposed on a surface of the crystalline silicon substrate, a doped polysilicon layer disposed on the tunneling passivation layer, and the protective layer is disposed on the doped polysilicon layer. Optionally, the battery matrix comprises a crystalline silicon substrate, a tunneling passivation layer arranged on the surface of the crystalline silicon substrate, and a doped silicon-containing film layer arranged on the tunneling passivation layer, wherein the doped silicon-containing film layer comprises amorphous silicon and/or microcrystalline silicon, and the protective layer is arranged on the doped silicon-containing film layer. Optionally, the first plating layer deposition sol