KR101251878B1 - Method for manufacturing bifacial solar cell - Google Patents

Abstract

PURPOSE: A method for manufacturing bifacial solar cells is provided to prevent thin film layers from being contaminated due to diffusion by using an amorphous thin film layer of a multilayer structure as a diffusion preventing layer. CONSTITUTION: A first amorphous thin film layer and a second amorphous thin film layer of a multilayer structure are deposited on the upper side and the lower side of a substrate(S110). Impurities included in the thin film layer are diffused to the substrate(S120). An emitter layer, a base layer, and a rear electric field layer are formed on the upper side, the middle side, and the lower side of the substrate respectively(S130). The first thin film layer and the second thin film layer are changed into a first diffusion byproduct oxide layer and a second diffusion byproduct oxide layer(S140). A front electrode and a rear electrode are formed on the surfaces of the first and second diffusion byproduct oxide layers(150). [Reference numerals] (AA) Start; (BB) End; (S100) Preparing a substrate; (S110) Depositing a first amorphous thin film layer and a second amorphous thin film layer on the upper side and the lower side of a substrate; (S120) Diffusing impurities included in the first and second amorphous thin film layers to the substrate by a thermal process; (S130) Forming an emitter layer, a base layer, and a rear electric field layer on the substrate; (S140) Changing the first thin film layer and the second thin film layer into a first diffusion byproduct oxide layer and a second diffusion byproduct oxide layer; (S150) Forming a front electrode and a rear electrode;

Description

Method for manufacturing double-sided light-receiving solar cell {Method for Manufacturing Bifacial Solar Cell}

The present invention relates to a method for manufacturing a double-sided light-receiving solar cell, and in particular, an amorphous thin film layer having a multi-layered structure having different conductivity types and concentrations of impurities is respectively laminated on the front and rear surfaces of the substrate, and the stacked amorphous thin film layers are used as a doping source and a diffusion barrier. By using one diffusion process to form the emitter layer and the rear electric field layer, while using the diffusion by-product oxide film formed on the front and back of the substrate as a passivation layer and anti-reflection film as a by-product of the diffusion process, The present invention relates to a method for manufacturing a double-sided light-receiving solar cell which can improve efficiency.

The solar cell is a key element of photovoltaic power generation that absorbs sunlight and converts it into electricity, and is basically a diode composed of a p-n junction.

In the process of converting sunlight into electricity by solar cells, solar light is incident on the solar cells to generate electron-hole pairs inside the solar cells, and electrons move to n layers and holes move to p layers by the electric field. Thus, photovoltaic power is generated between the pn junctions, and when a load or a system is connected to both ends of the solar cell, current flows to generate power.

On the other hand, solar cells are classified according to the type or impurity type of the light absorption layer that is the pn junction. The light absorption layer is typically silicon (Si), such a silicon-based solar cell according to the shape to light the silicon substrate itself It is divided into a silicon substrate type used as an absorbing layer and a thin film type which forms a light absorption layer by depositing silicon in a thin film form.

Looking at the general structure of the silicon substrate type of silicon-based solar cell as an example.

As shown in FIG. 1, the emitter layer 12 doped with the second conductive impurity is stacked on the base layer 11 doped with the first conductive impurity, and the finger bar or the upper portion of the emitter layer 12 is stacked. A front electrode 14 having a pattern such as a bus bar is formed, and a rear electric field layer 16 doped with a high concentration of a first conductivity type impurity is formed under the base layer 11, and the rear electric field layer 16 is formed. It has a structure in which the rear electrode 15 is formed as a whole. At this time, the base layer 11, the emitter layer 12 and the back electric field layer 16 is implemented on a single silicon substrate 10, the middle layer of the substrate 10 is the base layer 11, the upper layer is The emitter layer 12 and the lower layer are divided into the rear electric field layer 16.

Such a conventional solar cell is a cross-sectional light receiving type, and as the metallic back electrode 15 is formed on the rear surface of the substrate 10 as a whole, the manufacturing cost is high due to the consumption of a large amount of metal material, and the In this case, there is a problem in that the photoelectric conversion efficiency is lowered as the light collection amount is limited because it cannot be absorbed at all.

Therefore, recently, in order to overcome the problems of the conventional single-sided light-receiving solar cell that can absorb sunlight only by the front light-receiving unit, a double-sided light-receiving solar cell capable of receiving light on both sides of the front and rear has been developed. For example, Patent Document 1 discloses a double-sided light receiving solar cell and a manufacturing method thereof.

Such a double-sided light-receiving solar cell can not only absorb sunlight from the front light receiving unit, but also absorb light from the ground surface to the rear light receiving unit, thereby contributing to an increase in photoelectric conversion efficiency, thus building integrated solar power generation. Applications such as BIPV (Building Integrated Photovoltaic) are suitable for use in a wide range of photovoltaic modules.

In addition, since the double-sided light-receiving solar cell has a symmetrical structure having the same or similar metal electrodes on the front and the back, the surface area and the coefficient of thermal expansion of the front and rear electrodes that may be generated in the conventional single-sided light-receiving solar cell are different. Since the bending phenomenon can be minimized, it is possible to manufacture using a thin silicon substrate which is advantageous for cost reduction.

Referring to FIG. 2, a structure of a general double-sided light-receiving solar cell is described. Referring to FIG. 2, the second conductive type (eg and an emitter layer 12 doped with a p-type impurity to form a pn junction, and a front electrode 14 is provided on the emitter layer 12. In addition, the lower surface of the substrate 10 is provided with a rear electric field layer 16 and a rear electrode 15 doped with impurities of the first conductivity type, and an anti-reflection film 13 is provided on the front and rear surfaces of the substrate 10, respectively. do.

Looking at the manufacturing process of a double-sided light-receiving solar cell having such a structure, first preparing a substrate 10 of the first conductive silicon material, the surface texturing of the prepared substrate 10, the first on the substrate 10 Pn junction of emitter layer 12 and base layer 11 is formed through two-conductor type impurity ion doping and diffusion, and the first conductive type impurity is formed under the substrate 10. Forming a high-low junction of the back surface field layer 16 through ion implantation and diffusion, forming an anti-reflection film 13 on the top and bottom of the substrate 10, the front electrode 14 and the back electrode ( 15) It is manufactured through a process such as formation.

Meanwhile, before forming the anti-reflection film 13, diffusion by-products, which are diffusion by-products including impurities such as a PSG (Phosphorus Silicate Glass) film or a BSG (Boron Silicate Glass) film formed on the surface of the substrate 10 by heat treatment during the diffusion process, are formed. A cleaning process for removing an oxide film, an etching process for removing a diffusion barrier, or an etching process for removing an unnecessary doping layer formed on one surface of the substrate 10 may be performed.

Therefore, in order to manufacture a double-sided light-receiving solar cell, a plurality of diffusion processes must be performed in advance, and a step of forming a diffusion barrier layer before the diffusion process or an etching of one surface of the substrate 10 after the diffusion process is doped. Since a process of removing the layer is required, and a cleaning process or the like must be performed to remove the diffusion by-product oxide film after the diffusion process, there is a problem that the manufacturing process is complicated, resulting in an increase in manufacturing cost.

KR1004038030000 B1

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the amorphous thin film layer of the multilayer structure having different conductivity types and concentrations of impurities are respectively laminated on the front and rear surfaces of the substrate, respectively, and the stacked amorphous thin film layers are doped source and diffusion barrier layers. By forming a emitter layer and a rear electric field layer by using a single diffusion process, and using a diffusion by-product oxide film formed on the front and rear surfaces of the substrate as a passivation layer and an anti-reflection film as a by-product of the diffusion process. It is an object of the present invention to provide a method for manufacturing a double-sided light-receiving photovoltaic cell that can improve process efficiency.

In addition, the present invention uses a multi-layered amorphous thin film layer stacked on the front and rear surfaces of the substrate as a diffusion barrier layer, thereby preventing cross diffusion contamination between the amorphous thin film layer containing impurity ions of different conductivity type during the diffusion process and preventing contamination from the outside. To prevent it, for that purpose.

Method for manufacturing a double-sided light-receiving solar cell according to an embodiment of the present invention for achieving the above object comprises the steps of preparing a substrate of a silicon material of the first conductive type; Depositing a first amorphous thin film layer and a second amorphous thin film layer having a multi-layered structure on the upper and lower surfaces of the substrate, each containing impurities of different conductivity types; By performing a heat treatment process, impurities contained in the first amorphous thin film layer and the second amorphous thin film layer are diffused into the substrate, and the emitter layer, the base layer, and the rear electric field layer are respectively formed on the upper layer, the middle layer, and the lower layer of the substrate. Forming and converting the first amorphous thin film layer and the second amorphous thin film layer into a first diffusion oxide film and a second diffusion oxide film that serve as passivation and light reflection prevention, respectively; And printing a conductive paste on the surfaces of the first diffused by-oxide oxide film and the second diffused by-oxide oxide film, respectively, and firing to form a front electrode and a rear electrode.

Alternatively, preparing a first conductive silicon substrate; Depositing a first amorphous thin film layer and a second amorphous thin film layer having a multi-layered structure on the upper and lower surfaces of the substrate, each containing impurities of different conductivity types; By performing a heat treatment process, impurities contained in the first amorphous thin film layer and the second amorphous thin film layer are diffused into the substrate, and the emitter layer, the base layer, and the rear electric field layer are respectively formed on the upper layer, the middle layer, and the lower layer of the substrate. Forming and converting the first amorphous thin film layer and the second amorphous thin film layer into a first diffusion oxide film and a second diffusion oxide film that serve as passivation and light reflection prevention, respectively; Stacking an antireflection film on an upper portion of the first diffusion oxide film and a lower portion of the second diffusion oxide film; It is preferable to include a step of printing a conductive paste on the surface of each anti-reflection film laminated on the upper and lower portions of the substrate, and baking to form a front electrode and a rear electrode.

The depositing of the first amorphous thin film layer and the second amorphous thin film layer may include depositing a first amorphous thin film including a second conductive impurity on an upper surface of the substrate; Depositing a second amorphous thin film containing a first conductive impurity on a lower surface of the substrate; And depositing an intrinsic amorphous thin film on the upper portion of the first amorphous thin film and the lower portion of the second amorphous thin film, respectively.

In addition, in the step of converting the first diffusion Busan oxide film and the second diffusion Busan oxide film, the first amorphous thin film layer and the impurities contained in the first amorphous thin film layer and the second amorphous thin film layer through the heat treatment process and It is preferable to grow the second amorphous thin film layer to convert the first diffusion byproduct oxide film and the second diffusion byproduct oxide film which are diffusion byproducts.

On the other hand, the manufacturing method of a double-sided light receiving solar cell according to another embodiment of the present invention, preparing a substrate of the first conductive silicon material; Depositing a first amorphous thin film layer having a multi-layer structure on the upper surface of the substrate, the impurities including a second conductive type impurity; The substrate on which the first amorphous thin film layer is deposited on the upper surface is placed in a furnace filled with impurity ions of the first conductivity type, and heat-treated to implant and diffuse the impurity ions of the first conductivity type to the lower surface of the substrate. And diffusing impurities contained in the first amorphous thin film layer to form an emitter layer, a base layer, and a rear electric field layer on the upper, middle, and lower layers of the substrate, respectively, and passivating the first amorphous thin film layer. And converting the first diffused by-oxide oxide layer to prevent light reflection and forming a second diffused-oxide oxide layer on a lower surface of the substrate. And printing a conductive paste on the surfaces of the first diffused by-oxide oxide film and the second diffused by-oxide oxide film, respectively, and firing to form a front electrode and a rear electrode.

Alternatively, preparing a first conductive silicon substrate; Depositing a first amorphous thin film layer having a multi-layer structure on the upper surface of the substrate, the impurities including a second conductive type impurity; The substrate on which the first amorphous thin film layer is deposited on the upper surface is placed in a furnace filled with impurity ions of the first conductivity type, and heat-treated to implant and diffuse the impurity ions of the first conductivity type to the lower surface of the substrate. And diffusing impurities contained in the first amorphous thin film layer to form an emitter layer, a base layer, and a rear electric field layer on the upper, middle, and lower layers of the substrate, respectively, and passivating the first amorphous thin film layer. And converting the first diffused by-oxide oxide layer to prevent light reflection and forming a second diffused-oxide oxide layer on a lower surface of the substrate. Stacking an antireflection film on an upper portion of the first diffusion oxide film and a lower portion of the second diffusion oxide film; It is preferable to include a step of printing a conductive paste on the surface of each anti-reflection film laminated on the upper and lower portions of the substrate, and baking to form a front electrode and a rear electrode.

The depositing of the first amorphous thin film layer may include depositing a first amorphous thin film including a second conductive impurity on an upper surface of the substrate; And depositing an intrinsic amorphous thin film on top of the first amorphous thin film.

In the forming of the second diffusion by-oxide oxide layer, the first amorphous thin film layer is grown while the impurities contained in the first amorphous thin film layer are consumed through the heat treatment to be converted into the first diffusion by-product oxide layer which is a diffusion byproduct. It is preferable to make it.

According to the method of manufacturing a double-sided light-receiving solar cell according to the present invention, an amorphous thin film layer having a multilayer structure having different conductivity types and concentrations of impurities is respectively laminated on the front and rear surfaces of a substrate, and the stacked amorphous thin film layers are used as a doping source and a diffusion barrier. A single diffusion process is performed to form the emitter layer and the rear electric field layer, while the diffusion by-product oxides formed on the front and rear surfaces of the substrate as passivation layers and anti-reflection films are used as by-products of the diffusion process. Increasing the collection amount has the effect of improving the photoelectric conversion efficiency, simplifying the manufacturing process and cost reduction.

In addition, according to the method for manufacturing a double-sided light-receiving solar cell according to the present invention, using an amorphous thin film layer having a multilayer structure stacked on the front and rear surfaces of the substrate as a diffusion barrier layer, the mutual thin film layer including the amorphous thin film layer containing impurity ions of different conductivity type in the diffusion process. By preventing diffusion pollution and preventing pollution from the outside, there is an effect of improving the photoelectric conversion efficiency of the solar cell.

1 is a cross-sectional view of a general cross-sectional light receiving solar cell.
2 is a cross-sectional view of a typical double-sided light receiving solar cell.
3 is a cross-sectional view of a double-sided light receiving solar cell according to an embodiment of the present invention.
Figure 4 is a flow chart of a double-sided light receiving solar cell manufacturing method according to an embodiment of the present invention.
5 to 7 are cross-sectional views illustrating a method of manufacturing a double-sided light receiving solar cell according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to a double-sided light receiving solar cell according to a preferred embodiment of the present invention and a method of manufacturing the same.

Referring to FIG. 3, in the double-sided light receiving solar cell according to the exemplary embodiment of the present invention, the emitter layer 12 doped with the second conductive impurity is disposed on the base layer 11 doped with the first conductive impurity. A front electrode 14 having a pattern such as a finger bar or a bus bar is formed on the emitter layer 12, and a rear electric field layer doped with a high concentration of a first conductive type impurity under the base layer 11. 16 is formed, and the rear electrode 15 having a pattern such as a finger bar or a bus bar is formed below the rear electric field layer 16. Here, the first conductivity type may be n type or p type, hereinafter, the first conductive type is n type, and the second conductive type is p type.

In addition, the base layer 11, the emitter layer 12, and the rear electric field layer 16 are implemented on one silicon substrate 10, and the middle layer of the silicon substrate 10 is the base layer 11, and the upper layer is Emmy. The ground layer 12 and the lower layer are divided into a rear electric field layer 16. Since the rear electric field layer 16 has a higher energy barrier than the base layer 11, it prevents the minority carriers photogenerated by solar incident in the base layer 11 from moving to the rear electrode 15. At the same time, the photo-generated multiple carriers perform a passivation role to easily move to the rear electrode 15.

In addition, the first diffused by-oxide oxide film 20, which functions as a passivation and light reflection prevention layer, is stacked on the upper surface of the emitter layer 12 except for the formation portion of the front electrode 14, and the formation portion of the rear electrode 15 is formed. On the lower surface of the rear electric field layer 16 except for the second diffusion by-product oxide layer 22 which serves to passivation and prevent light reflection is stacked.

On the other hand, although not shown in the figure, an antireflection film made of silicon nitride (SiNx) or the like may be stacked on the surfaces of the first and second diffusion oxide films 20 and 22, respectively, to increase light reflection prevention efficiency. have.

In the above-described configuration, a method of manufacturing a double-sided light receiving solar cell according to an embodiment of the present invention will be described with reference to FIG. 4 as follows.

First, a substrate 10 made of crystalline silicon (Si) material of a first conductivity type is prepared (S100).

In step S100, a saw damage etching process of etching the substrate 10 in a chemical manner is performed in order to remove a defect portion generated as a result of the cutting process of the substrate 10, which is a pretreatment process. At this time, it is preferable to etch the surface of the substrate 10 by a predetermined depth using a potassium hydroxide (KOH) solution or the like as an etching solution, and then wash using DIW (Deionized Water).

In addition, after the saw damage etching process, it is preferable to form a concave-convex structure on the surface of the substrate 10 by performing a wet texturing process or a dry texturing process using an acid or alkali. .

In the state in which the substrate 10 is prepared through the above step S100, as shown in FIG. 5, the first amorphous thin film layer 21 including impurities of different conductivity types on the upper and lower surfaces of the substrate 10 and The second amorphous thin film layer 23 is deposited (S110).

In step S110, the first amorphous thin film 21-1 containing the second conductive impurity is deposited on the upper surface of the substrate 10, and the second amorphous including the first conductive impurity on the lower surface of the substrate 10. After depositing the thin film 23-1, the upper surface of the first amorphous thin film 21-1 and the lower surface of the second amorphous thin film 23-1 are respectively applied to another substrate close to each other during the heat treatment process of step S120. Depositing intrinsic amorphous thin films 21-2 and 23-2 that serve as a diffusion barrier to prevent cross diffusion contamination that may be caused by an out diffusion phenomenon from a doping source such as a deposited amorphous thin film. It is desirable to carry out the procedure.

In this case, the first amorphous thin film 21-1 and the second amorphous thin film 23-1 may be, for example, an amorphous silicon (a-Si) thin film containing a second conductive impurity or an amorphous silicon oxide (a-SiOx or a- SiOx: H) thin film, amorphous silicon nitride (a-SiNx) thin film, amorphous silicon carbide (a-SiCx) thin film, amorphous carbon (aC) thin film or amorphous aluminum oxide (a-AlOx) thin film, and the like, intrinsic amorphous The thin films 21-2 and 23-2 are, for example, intrinsic amorphous silicon (a-Si) thin films, intrinsic amorphous silicon oxide (a-SiOx or a-SiOx: H) thin films, and intrinsic amorphous silicon nitride (a-SiNx) thin films. , An intrinsic amorphous silicon carbide (a-SiCx) thin film, an intrinsic amorphous carbon (aC) thin film, or an intrinsic amorphous aluminum oxide (a-AlOx) thin film.

In addition, the first amorphous thin film layer 21 and the second amorphous thin film layer 23 respectively deposited on the upper and lower surfaces of the substrate 10 in step S110 are, for example, 5 nanometers (nm) to 100 nanometers (nm), respectively. It is preferably deposited to have a thickness within the range, with a thickness of 10 nanometers (nm) to 20 nanometers (nm).

In addition, in step S110, it is preferable to perform a cross-sectional deposition process in which the first amorphous thin film layer 21 and the second amorphous thin film layer 23 are respectively deposited on only one surface of the substrate 10. The single-sided deposition process is sputtering, which is a Plasma Enhanced Chemical Vapor Deposition (PECVD) method, an Atmospheric Pressure Chemical Vapor Deposition (APCVD) method, a Hot Wire (CVD) method, a Low Pressure Chemical Vapor Deposition (LPCVD) method, and a physical vapor deposition method. It may be implemented through a Sputtering method or an EVA (Evaporation) method.

After the above step S110, a heat treatment process is performed to diffuse impurities contained in the first amorphous thin film layer 21 and the second amorphous thin film layer 23 into the substrate 10 (S120).

The heat treatment process in the above step S120, for example, put the substrates are deposited on the upper and lower portions of the first amorphous thin film layer 21 and the second amorphous thin film layer 23 in the oxygen atmosphere, and then at a temperature within the range of 800 ℃ to 1200 ℃ It proceeds for a time within the range of about 10 minutes to 100 minutes, but preferably for a time within the range of about 20 minutes to 60 minutes at a temperature in the range of 900 ℃ to 1000 ℃.

Through the heat treatment process in step S120 described above, as shown in FIG. 6, the first amorphous thin film 21-1 of the first amorphous thin film layer 21 and the second amorphous thin film 23 of the second amorphous thin film layer 23. The impurities contained in -1) are thermally diffused to the inside of the substrate 10 while the impurities included in the -1) are discharged into the upper, middle and lower portions of the substrate 10, respectively, the emitter layer 12, the base layer 11, and A rear electric field layer 16 is formed (S130).

As described above, an additional isolation process is not required because the emitter layer 12 is formed on the upper layer of the substrate 10, the base layer 11 is formed on the middle layer, and the rear electric field layer 16 is formed on the lower layer. Will not.

On the other hand, through the heat treatment process in step S120 described above, the oxidation process is also carried out, and thus the first amorphous thin film layer 21 and the second amorphous thin film layer respectively deposited on upper and lower surfaces of the substrate 10 ( 23) is grown to a thickness having an optimal passivation characteristics as the impurities contained are almost consumed and converted into a first diffusion by-product oxide film 20 and a second diffusion by-product oxide film 22 which are diffusion by-products (S140).

In the step S140, the first diffusion oxide film 20 and the second diffusion oxide film 22 have a property of a dielectric layer as the impurities are almost consumed, and thus can be used as a passivation layer and an anti-radiation film. .

For example, the first diffusion oxide oxide film 20 converted through the step S140 may be an amorphous silicon thin film doped with boron (B) as the first amorphous thin film 21-1 of the first amorphous thin film layer 21, or When an amorphous silicon oxide thin film is used, it may be made of BSG, and the second diffused by-oxide oxide layer 22 is an amorphous doped with phosphorus (P) to the second amorphous thin film 23-1 of the second amorphous thin film layer 23. When a silicon thin film or an amorphous silicon oxide thin film is used, it may be made of PSG.

In addition, the first diffused by-product oxide film 20 and the second diffused by-product oxide film 22 converted through the above-described step S140 may be formed to have a thickness within a range of, for example, 10 nanometers (nm) to 120 nanometers (nm), respectively. That is, it is preferably formed to have a thickness of 60 nanometers (nm) to 100 nanometers (nm).

Since the steps S120 to S140 may be performed sequentially or in parallel in a single high temperature heat treatment process, the solar cell manufacturing process may be simplified.

After the above step S140, conductive front electrodes 14 and rear electrodes 15 are formed on upper and lower portions of the substrate 10, respectively (S150).

In the step S150 described above, as shown in FIG. 7, the conductive pastes 14-1 and 15-1 made of silver (Ag) or an alloy of silver (Ag) and aluminum (Al) or the like are prepared. The front electrode is printed by double printing on the surfaces of the first diffused by-product oxide film 20 and the second diffused by-product oxide film 22 respectively formed on the upper and lower portions of the substrate 10 and performing a co-firing process. 14 and the back electrode 15 are preferably formed.

On the other hand, after the above step S140, silicon nitride (SiNx) having a predetermined thickness is deposited on the upper portion of the first diffused by-product oxide film 20 and the lower portion of the second diffused by-product oxide film 22 to increase the light reflection prevention efficiency. After the deposition of the antireflection film, the conductive pastes 14-1 and 15-1 made of silver (Ag) or an alloy of silver (Ag) and aluminum (Al) are doubled on the surface of the laminated antireflection film. The above-described step S150 may be performed by a printing method of printing and performing a co-firing process.

Alternatively, in the state in which the substrate 10 is prepared through the above step S100, the first amorphous thin film layer 21 is deposited on the upper surface of the substrate 10, and then the first amorphous thin film layer 21 is deposited on the upper surface. The substrate 10 is placed in a furnace filled with impurity ions of the first conductivity type and heat-treated to inject and diffuse the impurity ions of the first conductivity type into the lower surface of the substrate 10, thereby performing step S130. And converting the first amorphous thin film layer 21 into the first diffused by-product oxide film 20, and as the lower surface of the substrate 10 is oxidized, the second diffused by-product oxide film 22 is formed on the lower surface of the substrate 10. May be formed. At this time, the first amorphous thin film layer 21 is a doping source for diffusing impurities of the second conductive type on the upper surface of the substrate during the heat treatment for implanting and diffusing the first conductive type impurity ions on the lower surface of the substrate 10 And a diffusion barrier for preventing implantation and diffusion of impurity ions of the first conductivity type on the upper surface of the substrate 10.

The method for manufacturing a double-sided light-receiving solar cell according to the present invention is not limited to the above-described embodiments, and may be variously modified and implemented within the range permitted by the technical idea of the present invention.

10: substrate 11: base layer
12: emitter layer 13: antireflection film
14: front electrode 15: rear electrode
14-1, 15-1: conductive paste 16: rear electric field layer
20: first diffusion Busan oxide film 21: first amorphous thin film layer
21-1: first amorphous thin film 21-2, 23-2: intrinsic amorphous thin film
22: second diffusion Busan oxide film 23: the second amorphous thin film layer
23-1: second amorphous thin film

Claims (8)

Preparing a first conductive silicon substrate;
Depositing a first amorphous thin film layer and a second amorphous thin film layer having a multi-layered structure on the upper and lower surfaces of the substrate, each containing impurities of different conductivity types;
By performing a heat treatment process, impurities contained in the first amorphous thin film layer and the second amorphous thin film layer are diffused into the substrate, and the emitter layer, the base layer, and the rear electric field layer are respectively formed on the upper layer, the middle layer, and the lower layer of the substrate. Forming and converting the first amorphous thin film layer and the second amorphous thin film layer into a first diffusion oxide film and a second diffusion oxide film that serve as passivation and light reflection prevention, respectively;
A method of manufacturing a double-sided light-receiving photovoltaic cell, comprising: printing a conductive paste on the surfaces of the first diffusion oxide film and the second diffusion oxide film, and baking the same to form a front electrode and a back electrode.
Preparing a first conductive silicon substrate;
Depositing a first amorphous thin film layer and a second amorphous thin film layer having a multi-layered structure on the upper and lower surfaces of the substrate, each containing impurities of different conductivity types;
By performing a heat treatment process, impurities contained in the first amorphous thin film layer and the second amorphous thin film layer are diffused into the substrate, and the emitter layer, the base layer, and the rear electric field layer are respectively formed on the upper layer, the middle layer, and the lower layer of the substrate. Forming and converting the first amorphous thin film layer and the second amorphous thin film layer into a first diffusion oxide film and a second diffusion oxide film that serve as passivation and light reflection prevention, respectively;
Stacking an antireflection film on an upper portion of the first diffusion oxide film and a lower portion of the second diffusion oxide film;
And printing a conductive paste on the surfaces of the anti-reflection films stacked on the upper and lower parts of the substrate, and baking the same to form a front electrode and a back electrode.
The method according to claim 1 or 2,
Depositing the first amorphous thin film layer and the second amorphous thin film layer,
Depositing a first amorphous thin film including a second conductive impurity on an upper surface of the substrate;
Depositing a second amorphous thin film containing a first conductive impurity on a lower surface of the substrate;
And depositing an intrinsic amorphous thin film on the upper portion of the first amorphous thin film and the lower portion of the second amorphous thin film, respectively.
The method of claim 3,
In the converting into the first diffusion and oxide oxide film and the second diffusion and oxide oxide film, the first amorphous thin film layer and the second and the second amorphous thin film layer while consuming impurities contained in the first amorphous thin film layer and the second amorphous thin film layer A method of manufacturing a double-sided light-receiving photovoltaic cell, comprising: growing an amorphous thin film layer to convert the first diffusion diffusion oxide film and the second diffusion diffusion oxide film as diffusion byproducts.
Preparing a first conductive silicon substrate;
Depositing a first amorphous thin film layer having a multi-layer structure on the upper surface of the substrate, the impurities including a second conductive type impurity;
The substrate on which the first amorphous thin film layer is deposited on the upper surface is placed in a furnace filled with impurity ions of the first conductivity type, and heat-treated to implant and diffuse the impurity ions of the first conductivity type to the lower surface of the substrate. And diffusing impurities contained in the first amorphous thin film layer to form an emitter layer, a base layer, and a rear electric field layer on the upper, middle, and lower layers of the substrate, respectively, and passivating the first amorphous thin film layer. And converting the first diffused by-oxide oxide layer to prevent light reflection and forming a second diffused-oxide oxide layer on a lower surface of the substrate.
A method of manufacturing a double-sided light-receiving photovoltaic cell, comprising: printing a conductive paste on the surfaces of the first diffusion oxide film and the second diffusion oxide film, and baking the same to form a front electrode and a back electrode.
Preparing a first conductive silicon substrate;
Depositing a first amorphous thin film layer having a multi-layer structure on the upper surface of the substrate, the impurities including a second conductive type impurity;
The substrate on which the first amorphous thin film layer is deposited on the upper surface is placed in a furnace filled with impurity ions of the first conductivity type, and heat-treated to implant and diffuse the impurity ions of the first conductivity type to the lower surface of the substrate. And diffusing impurities contained in the first amorphous thin film layer to form an emitter layer, a base layer, and a rear electric field layer on the upper, middle, and lower layers of the substrate, respectively, and passivating the first amorphous thin film layer. And converting the first diffused by-oxide oxide layer to prevent light reflection and forming a second diffused-oxide oxide layer on a lower surface of the substrate.
Stacking an antireflection film on an upper portion of the first diffusion oxide film and a lower portion of the second diffusion oxide film;
And printing a conductive paste on the surfaces of the anti-reflection films stacked on the upper and lower parts of the substrate, and baking the same to form a front electrode and a back electrode.
The method according to claim 5 or 6,
Depositing the first amorphous thin film layer,
Depositing a first amorphous thin film including a second conductive impurity on an upper surface of the substrate;
A method of manufacturing a double-sided light receiving type solar cell, comprising depositing an intrinsic amorphous thin film on top of the first amorphous thin film.
The method of claim 7, wherein
In the forming of the second diffused by-oxide oxide layer, the first amorphous thin film layer is grown and converted into the first diffused by-product oxide layer which is a diffusion byproduct while consuming impurities contained in the first amorphous thin film layer through the heat treatment. A double-sided light receiving solar cell manufacturing method characterized in that.

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