WO2023213125A1 - Hbc solar cell, preparation method and cell assembly - Google Patents

Abstract

Provided in the present application are an HBC solar cell, a preparation method and a cell assembly, relating to the technical field of solar cells. The HBC solar cell comprises a silicon substrate, and, a first transmission layer, a second transmission layer, an insulation layer and an insulation protection layer used for protecting the insulation layer, which are all located on the backlight side of the silicon substrate, wherein a first projection of the second transmission layer on the backlight surface of the silicon substrate and a second projection of the first transmission layer on the backlight surface of the silicon substrate have an overlapping area and a non-overlapping area; the insulation layer and the insulation protection layer are both located between the first transmission layer and the second transmission layer, and completely cover the overlapping area; the insulation protection layer is distributed closely next to the insulation layer, and the insulation protection layer is located on the side of the insulation layer away from the silicon substrate, and in the same etching condition, the etch rate of the insulation protection layer is smaller than the etch rate of the insulation layer. The etch rate of the insulation protection layer is lower, so that the insulation protection layer will well protect the insulation layer, thus improving the insulation performance of an HBC solar cell.

Description

HBC solar cell, preparation method and battery component

This application claims priority to the Chinese patent application filed with the China Patent Office on May 5, 2022, with application number 202210483266.0 and titled "A HBC solar cell, preparation method, and battery module", the entire content of which is incorporated by reference. in this application.

Technical field

The present application relates to the technical field of solar cells, and in particular to an HBC solar cell, its preparation method, and battery components.

Background technique

Back-contact heterojunction solar cells (Heterojunction-IBC, HBC for short), because the electrodes are arranged on the backlight surface of the battery, can effectively reduce short-circuit current loss and have broad application prospects.

In existing HBC solar cells, the insulation performance is poor, resulting in low efficiency of HBC solar cells.

Application content

This application provides an HBC solar cell, a preparation method, and a battery component, aiming to solve the problem of poor insulation performance in existing HBC solar cells.

The first aspect of this application provides a method for preparing HBC solar cells, including:

A silicon substrate, a first transmission layer, a second transmission layer, an insulating layer, and an insulating protective layer for protecting the insulating layer, all located on the backlight side of the silicon substrate; the first transmission layer and the second transmission layer The doping types are different;

The first projection of the second transmission layer on the backlight surface of the silicon substrate and the second projection of the first transmission layer on the backlight surface of the silicon substrate have overlapping areas and non-overlapping areas; The insulating layer and the insulating protective layer are both located between the first transmission layer and the second transmission layer and completely cover the overlapping area; the insulating protective layer and the insulating layer are distributed adjacent to each other, and the insulating protective layer A layer is located on a side of the insulating layer away from the silicon substrate;

Under the same etching conditions, the etching rate of the insulating protective layer is lower than the etching rate of the insulating layer.

In the embodiment of the present application, the insulating layer and the insulating protective layer are distributed closely together, and the insulating protective layer is located on the side of the insulating layer away from the silicon substrate. Under the same etching conditions, the etching rate of the insulating protective layer is lower than the etching rate of the insulating layer. Furthermore, in the process of patterning each layer in the HBC solar cell, whether it is laser etching or acid etching, Regardless of etching or alkaline etching, the etching rate of the insulating protective layer is slow. The insulating protective layer located on the side of the insulating layer away from the silicon substrate will play a good protective role in the insulating layer, so that the insulating layer will basically not be damaged. Or influence, it can improve the insulation performance of HBC solar cells, basically avoiding the problem that the HBC preparation process is difficult to proceed smoothly, and also basically avoiding the problem of decreased efficiency of solar cells due to damage to the insulation layer.

Optionally, under the same alkali etching conditions, the etching rate of the insulating layer is 30-1800 times that of the insulating protective layer.

Optionally, under alkali etching conditions of 50-150°C and alkali etching solution mass concentration of 0.1%-1.2%: the etching rate of the insulating layer is 300-1800nm/min, and the insulating protective layer The etching rate is 1-10nm/min.

Optionally, the material of the insulating protective layer is selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, silicon oxide containing P-type doped substances, silicon carbide containing P-type doped substances. material, silicon nitride containing P-type doping material, at least one of the six types.

Optionally, the insulating protective layer has a single-layer structure or a stacked structure.

Optionally, the thickness of the insulating protective layer is 1 nm-2um; the thickness of the insulating protective layer is: the size of the insulating protective layer in the stacking direction of the silicon substrate and the insulating layer.

Optionally, the insulating protective layer includes at least one P-type layer and at least one intrinsic amorphous silicon layer, and the side of the insulating protective layer away from the silicon substrate is a P-type layer;

The material of the P-type layer is selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, silicon oxide containing P-type doped substances, silicon carbide containing P-type doped substances, P-containing Silicon nitride of type doped material, at least one of six types.

Optionally, the insulating protective layer is composed of a first P-type layer, an intrinsic amorphous silicon layer, and a second P-type layer stacked in sequence; or, the insulating protective layer is composed of a stacked third P-type layer, an intrinsic amorphous silicon layer, and a second P-type layer. Composed of amorphous silicon layer.

Optionally, the insulating protective layer includes: at least one of a boron-doped silicon oxide layer, a boron-doped silicon carbide layer, and a boron-doped silicon nitride layer.

Optionally, the material of the insulating layer is selected from silicon nitride and/or silicon oxide.

Optionally, the HBC solar cell further includes: a first back passivation layer, a second back passivation layer, a transparent conductive layer, a first electrode and a third back passivation layer located on the same side of the silicon substrate as the insulating layer. two electrodes;

The first back passivation layer and the first transmission layer are both located between the silicon substrate and the insulating layer, and the first transmission layer is located away from the first back passivation layer and the silicon substrate. one side; the second projection of the first transmission layer on the silicon substrate overlaps with the third projection of the first back passivation layer on the silicon substrate; the first back passivation layer Distributed intermittently on the silicon substrate;

The second backside passivation layer includes a flush portion distributed flush with the first backside passivation layer, the flush portion is located at an interrupted position of the first backside passivation layer, and is flush with the first backside passivation layer. The backside passivation layer forms an entire layer covering the silicon substrate;

The second backside passivation layer, the second transmission layer, and the transparent conductive layer are sequentially stacked on the side of the insulating protective layer away from the silicon substrate; the transparent conductive layer is not placed on the overlapping area. continuous;

The first electrode and the second electrode are both located at positions corresponding to the non-overlapping areas on the transparent conductive layer, and the first electrode corresponds to the first transmission layer, and the second electrode and The second transport layer position corresponds.

A second aspect of the present application provides a battery component, including: at least one HBC solar cell as described above.

The third aspect of this application provides a method for preparing HBC solar cells, including:

A first transmission layer, an insulating layer and an insulating protective layer for protecting the insulating layer are sequentially formed on the backlight side of the silicon substrate; under the same etching conditions, the etching rate of the insulating protective layer is smaller than that of the insulating layer. The etching rate of the layer;

Use a laser to open the insulating protective layer so that the insulating layer is exposed;

Remove the exposed portion of the insulating layer and the portion of the first transmission layer corresponding to the opening;

A second transmission layer is formed on the remaining insulating protective layer and the backlight side of the silicon substrate; the first transmission layer and the second transmission layer have different doping types.

Optionally, forming an insulating protective layer includes:

The insulating protective layer is deposited on the insulating layer.

Optionally, forming an insulating protective layer includes:

At least one P-type layer is formed on the insulating layer; the material of the P-type layer is selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, and silicon oxide containing P-type doping substances. , silicon carbide containing P-type doping material, silicon nitride containing P-type doping material, at least one of the six types;

The method of using a laser to open an opening on the insulating protective layer includes:

forming an intrinsic amorphous silicon layer on the P-type layer;

The intrinsic amorphous silicon layer is used as a laser absorption layer, and a laser is used to make openings on the insulating protective layer.

Optionally, forming an insulating protective layer includes:

At least one P-type layer and at least one intrinsic amorphous silicon layer are formed on the insulating layer, and the side of the insulating protective layer away from the silicon substrate is a P-type layer; Materials are selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, silicon oxide containing P-type doped substances, silicon carbide containing P-type doped substances, silicon containing P-type doped substances Nitride, at least one of six species.

Optionally, forming an insulating protective layer includes:

forming a first P-type layer on the insulating layer;

forming an intrinsic amorphous silicon layer on the first P-type layer;

A second P-type layer is formed on the intrinsic amorphous silicon layer.

Optionally, before forming the first transmission layer, the method further includes:

Forming a first backside passivation layer on the backlight surface of the silicon substrate;

The forming the first transmission layer includes: forming the first transmission layer on the first backside passivation layer;

After removing the portion of the first transmission layer corresponding to the opening and before forming the second transmission layer, the method further includes:

Remove the portion of the first back passivation layer corresponding to the opening so that the silicon substrate is exposed;

Form a second backside passivation layer on the remaining insulating protective layer and the exposed silicon substrate;

The forming the second transmission layer includes:

forming the second transmission layer on the second backside passivation layer;

The method also includes:

Part of the area corresponding to the insulating layer in the second transmission layer and part of the area corresponding to the insulating layer in the second back surface passivation layer are sequentially removed, so that there is no gap between the second back surface passivation layer and the third back surface passivation layer. In the direction in which the two transmission layers are stacked, the second backside passivation layer and the second transmission layer are evenly distributed;

Use a laser to remove part of the area corresponding to the insulating layer in the insulating protective layer, so that in the direction in which the second backside passivation layer and the second transmission layer are stacked, the insulating protective layer and the second The backside passivation layer is distributed evenly.

The above-mentioned battery modules and preparation methods of HBC solar cells have the same or similar beneficial effects as the aforementioned HBC solar cells. To avoid repetition, they will not be described again here.

Description of the drawings

In order to explain the technical solutions of the embodiments of the present application more clearly, the drawings needed to be used in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. , for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without exerting creative labor.

Figure 1 shows a schematic structural diagram of the first HBC solar cell in the embodiment of the present application;

Figure 2 shows a schematic structural diagram of the second HBC solar cell in the embodiment of the present application;

Figure 3 shows a schematic structural diagram of the third HBC solar cell in the embodiment of the present application;

Figure 4 shows a schematic structural diagram of the fourth HBC solar cell in the embodiment of the present application;

Figure 5 shows a step flow chart of a method for preparing an HBC solar cell in an embodiment of the present application;

Figure 6 shows a partial structural diagram of the first HBC solar cell in the embodiment of the present application;

Figure 7 shows a partial structural schematic diagram of the second HBC solar cell in the embodiment of the present application;

Figure 8 shows a partial structural schematic diagram of the third HBC solar cell in the embodiment of the present application;

Figure 9 shows a partial structural schematic diagram of the fourth HBC solar cell in the embodiment of the present application;

Figure 10 shows a partial structural schematic diagram of the fifth HBC solar cell in the embodiment of the present application;

Figure 11 shows a partial structural diagram of the sixth HBC solar cell in the embodiment of the present application. picture;

Figure 12 shows a partial structural schematic diagram of the seventh HBC solar cell in the embodiment of the present application;

Figure 13 shows a partial structural schematic diagram of the eighth HBC solar cell in the embodiment of the present application;

Figure 14 shows a partial structural schematic diagram of the ninth HBC solar cell in the embodiment of the present application;

Figure 15 shows a partial structural diagram of the tenth HBC solar cell in the embodiment of the present application.

Explanation of drawing numbers:

1-Silicon substrate, 111-Backlight surface of silicon substrate, 222-Light facing surface of silicon substrate, 2-First back passivation layer, 3-First transmission layer, 4-Insulating layer, 5-Insulating protective layer, 51 -Intrinsic amorphous silicon layer, 52-P-type layer or third P-type layer, 521-first P-type layer, 522-second P-type layer, 6-opening, 9-second backside passivation layer, 10 -The second transmission layer, 11-front passivation layer, 12-front semiconductor layer, 13-front anti-reflection layer, 16-transparent conductive layer, 17-interrupted area in the transparent conductive layer, 18-first electrode, 19-Second electrode.

Specific embodiments

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

Figure 1 shows a schematic structural diagram of the first HBC solar cell in the embodiment of the present application. Referring to Figure 1, the HBC solar cell includes: a silicon substrate 1, and the doping type of the silicon substrate 1 is not specifically limited. For example, the silicon substrate 1 may be an N-type doped silicon substrate, or may be a P-type doped silicon substrate. In the embodiment of the present application, there is no specific limitation on this. The silicon substrate 1 includes a light facing surface and a backlight surface, both of which are relatively distributed.

Referring to FIG. 1 , the HBC solar cell also includes: a first transmission layer 3 located on the backlight side of the silicon substrate 1 , a second transmission layer 10 , an insulating layer 4 and an insulating protective layer 5 for protecting the insulating layer 4 . The doping types of the first transmission layer 3 and the second transmission layer 10 are opposite. That is, if one of the first transmission layer 3 and the second transmission layer 10 is an N-type transmission layer, the other one is a P-type transmission layer.

The first projection of the second transmission layer 10 on the backlight surface of the silicon substrate 1 and the second projection of the first transmission layer 3 on the backlight surface of the silicon substrate 1 have overlapping areas and non-overlapping areas. The insulating layer 4 and the insulating protective layer 5 are both located between the first transmission layer 3 and the second transmission layer 10 and completely cover the above-mentioned overlapping area. The insulating layer 4 is used to isolate the first transmission layer 3 and the second transmission layer 10 .

The applicant found that the main reason for the poor insulation performance of HBC solar cells in the prior art is that in the process of preparing HBC solar cells, many layers need to go through a patterning stage. For example, the transmission layer is patterned, and the transparent The conductive layer is patterned. During the above patterning process, whether laser etching or wet etching is used, the insulating layer 4 will be damaged. For example, whether it is acidic etching or alkaline etching, the insulating layer 4 will be damaged. Cause damage. The above-mentioned laser etching or wet etching damage to the insulating layer 4 mainly occurs in two situations. The first situation is that the insulating layer 4 is completely corroded by the laser etching or wet etching solution, making subsequent processes unable to proceed smoothly. ; The second case is that the insulating layer 4 is corroded by laser etching or wet etching solution into a porous structure, and the layers adjacent to the insulating layer 4 will remain in the holes of the insulating layer 4, and the above-mentioned residual substances will increase. Contact resistance reduces solar cell efficiency. In summary, in existing HBC solar cells, the insulating layer is corroded by laser etching or wet etching, resulting in poor insulation performance of the HBC solar cells.

In the embodiment of the present application, the insulating layer 4 and the insulating protective layer 5 are distributed closely together, and the insulating protective layer 5 is located on the side of the insulating layer 4 away from the silicon substrate 1 . Under the same etching conditions, the etching rate of the insulating protective layer 5 is lower than the etching rate of the insulating layer 4. Furthermore, in the process of patterning each layer in the HBC solar cell, whether it is laser etching, Whether in acidic etching or alkaline etching, the etching rate of the insulating protective layer 5 is slow. The insulating protective layer 5 located on the side of the insulating layer 4 away from the silicon substrate will play a good protective role in the insulating layer 4, making the insulation Layer 4 will basically not be damaged or affected, which can improve the insulation performance of HBC solar cells and basically avoid the problem of the HBC preparation process being difficult to proceed smoothly in the existing technology. At the same time, it also basically avoids the damage to solar cells caused by the destruction of insulation layer 4. The problem of reduced efficiency.

Optionally, under the same alkali etching conditions, the etching rate of the insulating layer 4 is 30-1800 times the etching rate of the insulating protective layer 5 . That is to say, under the same alkali etching conditions, the etching rate of the insulating layer 4 is much greater than the etching rate of the insulating protective layer 5 . Furthermore, the alkali etching solution proceeds from the side of the insulating protective layer 5 away from the insulating layer 4 During the etching process, the alkali etching solution will basically not damage the insulating protective layer 5, so that the insulating protective layer 5 has a good protective effect on the insulating layer 4, and the insulating layer 4 will basically not be damaged or affected, thereby improving the HBC solar energy Battery insulation properties.

It should be noted that silicon materials basically have good acid resistance. Therefore, in the process of patterning various layers in HBC solar cells, alkali etching solutions are often used. Therefore, in the embodiment of the present application, Under the same alkali etching conditions, the etching rate of the insulating layer 4 is 30-1800 times that of the insulating protective layer 5, so that the insulating protective layer 5 will damage the insulating layer during most patterning processes. 4 has good protective effect.

For example, intrinsic amorphous silicon, N-type silicon materials, P-type silicon materials, etc. basically have good acid resistance. In the process of patterning various layers in HBC solar cells, alkali etching solutions are often used. , under the same alkali etching conditions, the etching rate of the insulating layer 4 is 30-1800 times that of the insulating protective layer 5, so that the insulating protective layer 5 is suitable for most patterning processes. The insulating layer 4 has a good protective effect.

Optionally, under alkali etching conditions of 50-150°C and alkali etching solution mass concentration of 0.1%-1.2%: the etching rate of the insulating layer 4 is 300-1800nm/min, and the etching rate of the insulating protective layer 5 is The corrosion rate is 1-10nm/min. Specifically, the alkali etching conditions of 50-150°C and the mass concentration of the alkali etching solution of 0.1%-1.2% are commonly used alkali etching conditions in HBC solar cells. Under the commonly used alkali etching conditions, the insulating layer 4 The etching rate of the insulating protective layer 5 is 300-1800 nm/min, and the etching rate of the insulating protective layer 5 is only 1-10 nm/min. The etching rate of the insulating layer 4 is much greater than the etching rate of the insulating protective layer 5. Furthermore, alkali etching During the etching process of the etching solution from the side of the insulating protective layer 5 away from the insulating layer 4, the alkali etching solution will basically not damage the insulating protective layer 5, so that the insulating protective layer 5 has a good protective effect on the insulating layer 4. The insulating layer 4 will basically not be damaged or affected, thereby improving the insulation performance of the HBC solar cell.

For example, under alkali etching conditions of 80°C and a mass concentration of an alkali etching solution of 0.5%: the etching rate of the insulating layer 4 is 1200 nm/min, the etching rate of the insulating protective layer 5 is 8 nm/min, and the etching rate of the insulating layer 4 is 8 nm/min. The etching rate of 4 is 150 times that of the insulating protective layer 5. When the alkali etching solution etches from the side of the insulating protective layer 5 away from the insulating layer 4, the alkali etching solution will basically not break. The insulating protective layer 5 has a good protective effect on the insulating layer 4, and the insulating layer 4 is basically not damaged or affected, thereby improving the insulation performance of the HBC solar cell.

Optionally, the material of the insulating protective layer 5 is selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, silicon oxide containing P-type doping substances, and silicon carbide containing P-type doping substances. , Silicon nitride containing P-type doping material, at least one of the six types. The insulating protective layer 5 of the above material has a very low etching rate for the alkali etching solution, and the alkali etching solution enters from the side of the insulating protective layer 5 away from the insulating layer 4. During the etching process, the alkali etching solution will basically not damage the insulating protective layer 5 , so that the insulating protective layer 5 has a good protective effect on the insulating layer 4 . Moreover, the etching rate of the insulating protective layer 5 of the above material to the acid etching solution is also very small. When the acid etching solution etches from the side of the insulating protective layer 5 away from the insulating layer 4, the acid etching solution also The insulating protective layer 5 will basically not be damaged, so that the insulating protective layer 5 has a good protective effect on the insulating layer 4 .

Optionally, the insulating protective layer 5 has a single-layer structure or a stacked structure. When the insulating protective layer 5 has a laminated structure, the interfaces between the various layers of the insulating protective layer 5 will reflect light. If the laser etching process is used for patterning preparation, the laser reaching the lower layer will be smaller, which can play a role. Adjusting the role of the laser processing window can reduce laser damage to the passivation layer and increase the range of laser power, making it easier to achieve industrial production. At the same time, during the process of laser etching or wet etching, the stacked structure can increase the corrosion resistance of the insulating protective layer 5, making the protective effect on the insulating layer 4 better. If the insulating protective layer 5 has a laminated structure, the number of layers is not specifically limited.

Figure 2 shows a schematic structural diagram of the second HBC solar cell in the embodiment of the present application. Figure 3 shows a schematic structural diagram of the third HBC solar cell in the embodiment of the present application. Figure 4 shows a schematic structural diagram of the fourth HBC solar cell in the embodiment of the present application. For example, the insulating protective layer 5 shown in Figures 1 and 3 has a single-layer structure. The insulating protective layer 5 shown in Figures 2 and 4 has a laminated structure.

Optionally, the thickness of the insulating protective layer 5 is 1nm-2um. The thickness of the insulating protective layer 5 is: the size of the insulating protective layer 5 in the stacking direction of the silicon substrate 1 and the insulating layer 4. The insulating protective layer 5 in the above thickness range The etching rate of the etching solution is slower, and the protective effect on the insulating layer 4 is better. For example, the thickness of the insulating protective layer 5 is 1 nm, 20 nm, 100 nm, 1 um, or 2 um. More preferably, the thickness of the insulating protective layer 5 can be 3nm-500nm.

Optionally, as shown in FIG. 2 , the insulating protective layer 5 includes at least one P-type layer 52 and at least one intrinsic amorphous silicon layer 51 , and the side of the insulating protective layer 5 away from the silicon substrate 1 is P-type. Layer 52, the material of the P-type layer is selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, silicon oxide containing P-type doping substances, silicon carbide containing P-type doping substances, Silicon nitride with P-type doping material, at least one of six types. When the alkali etching solution or the acidic etching solution is etching from the side of the insulating protective layer 5 away from the insulating layer 4 , the alkali etching solution or the acidic etching solution will basically not damage the P-type layer 52 . 52 has a good protective effect on the intrinsic amorphous silicon layer 51, and the entire insulating layer 5 will basically not be damaged, so that the insulating protective layer 5 has a good protective effect on the insulating layer 4. same, The insulating protective layer 5 has a laminated structure. The interfaces between the various layers of the insulating protective layer 5 will reflect light. If the laser etching process is used for patterning preparation, the laser reaching the lower layer will be smaller, which can adjust the laser processing. The function of the window can reduce the damage of the laser to the passivation layer, and can increase the use range of the laser power, making it easier to achieve industrial production, and during the process of laser etching or wet etching, the stack The layer structure can increase the corrosion resistance of the insulating protective layer 5, making the protective effect on the insulating layer 4 better.

It should be noted that the number of P-type layers 52 and the number of intrinsic amorphous silicon layers 51 included in the insulating protective layer 5 is not specifically limited. It only needs to be ensured that the side of the insulating protective layer 5 away from the silicon substrate 1 is The P-type layer 52 can achieve the above function, and the relative position of the other layers is also not specifically limited.

Optionally, as shown in Figure 4, the insulating protective layer 5 is composed of a first P-type layer 521, an intrinsic amorphous silicon layer 51, and a second P-type layer 522 stacked in sequence, with an alkali etching solution or an acidic etching solution. During the etching process from the side of the insulating protective layer 5 away from the insulating layer 4 , the alkali etching solution or the acidic etching solution will basically not damage the P-type layer of the intrinsic amorphous silicon layer 51 on the side away from the silicon substrate 1 As shown in Figure 4, the second P-type layer 522 on the side of the intrinsic amorphous silicon layer 51 away from the silicon substrate 1 has a good protective effect on the intrinsic amorphous silicon layer 51, and the entire insulating layer 5 will not be damaged basically, so that the insulation The protective layer 5 has a good protective effect on the insulating layer 4 . Similarly, the insulating protective layer 5 has a laminated structure, and the interfaces between the various layers of the insulating protective layer 5 will reflect light. If the laser etching process is used for patterning preparation, the laser reaching the lower layer will be smaller, which can achieve Adjusting the role of the laser processing window can reduce the damage of the laser to the passivation layer, and can increase the use range of the laser power, making it easier to achieve industrial production, and use the laser etching process, or in the wet etching process , the stacked structure can increase the corrosion resistance of the insulating protective layer 5, making the protection of the insulating layer 4 better. At the same time, the first P-type layer 521 closest to the silicon substrate can also serve as the final barrier against etching, enhancing to protect the insulating layer 4.

Or, as shown in FIG. 2 , the insulating protective layer 5 is composed of a stacked third P-type layer 52 and an intrinsic amorphous silicon layer 51 . Similarly, the alkali etching solution or acidic etching solution is away from the insulating layer 5 . During the etching process on one side of layer 4, the alkali etching solution or acidic etching solution will basically not damage the third P-type layer 52 on the side of the intrinsic amorphous silicon layer 51 away from the silicon substrate 1. The molded layer 52 has a good protective effect on the intrinsic amorphous silicon layer 51 , and the entire insulating layer 5 is basically not damaged, so that the insulating protective layer 5 has a good protective effect on the insulating layer 4 . Similarly, the insulating protective layer 5 has a stacked structure, and the interfaces between the various layers of the insulating protective layer 5 will reflect light. If a laser etching process is used, Patterned preparation makes the laser reaching the lower layer smaller, which can adjust the laser processing window, reduce laser damage to the passivation layer, and increase the range of laser power, making it easier to achieve industrial production. , and in the process of laser etching or wet etching, the laminated structure can increase the corrosion resistance of the insulating protective layer 5, so that the protective effect on the insulating layer 4 is better.

Optionally, the above-mentioned insulating protective layer 5 includes at least one of: a boron-doped silicon oxide layer, a boron-doped silicon carbide layer, and a boron-doped silicon nitride layer. The above-mentioned insulating protective layer 5 is resistant to etching by acid and alkali etching solutions. The corrosion rate is slow, easy to obtain, and low cost.

Optionally, the material of the insulating layer 4 is selected from: silicon nitride and/or silicon oxide. The insulating layer 4 of the above materials has good insulation effect, is easy to obtain, and has a low cost.

Optionally, referring to Figures 1 to 4, the HBC solar cell also includes: a first back passivation layer 2, a second back passivation layer 9, a transparent Conductive layer 16, first electrode 18 and second electrode 19.

The first back passivation layer 2 and the first transmission layer 3 are both located between the silicon substrate 1 and the insulating layer 4 , and the first transmission layer 3 is located on the side of the first back passivation layer 2 away from the silicon substrate 1 . The second projection of the first transmission layer 3 on the silicon substrate 1 overlaps with the third projection of the first backside passivation layer 2 on the silicon substrate 1 . The first backside passivation layer 2 is intermittently distributed on the silicon substrate 1 , so the first transmission layer 3 is also intermittently distributed on the silicon substrate 1 .

The second backside passivation layer 9 includes a flush portion distributed flush with the first backside passivation layer 2 . The flush portion is located at the discontinuous position of the first backside passivation layer 2 and covers the first backside passivation layer 2 . A whole layer of the silicon substrate 1, so that the backlight surface of the silicon substrate 1 has a whole layer of back passivation layer, and the passivation effect is good.

The second backside passivation layer 9, the second transmission layer 10, and the transparent conductive layer 16 are sequentially stacked on the side of the insulating protective layer 5 away from the silicon substrate 1. The transparent conductive layer 16 is discontinuous in the overlapping area to avoid short circuit.

The first electrode 18 and the second electrode 19 are both located at positions corresponding to the non-overlapping areas on the transparent conductive layer 16 , and the first electrode 18 corresponds to the first transmission layer 3 . The first electrode 18 is used to collect and conduct the first transmission 3 The positions of the second electrode 19 and the second transmission layer 10 are corresponding to the corresponding carriers, and the second electrode 19 is used to collect and conduct the corresponding carriers of the second transmission layer 10 .

Optionally, the material of the first backside passivation layer 2 may be intrinsic amorphous silicon. first back passivation layer The thickness of 2 may be 3-15 nm, and the direction of the thickness is parallel to the stacking direction of the silicon substrate 1 and the first back passivation layer 2. The directions of thickness and height mentioned in the entire text are the same as this definition. The thickness of the first transmission layer 3 may be 3-20 nm, and the thickness of the insulating layer 4 may be 50-500 nm. The material of the second backside passivation layer 9 may be intrinsic amorphous silicon. The thickness of the second backside passivation layer 9 may be 5-20 nm.

The present application also provides a battery assembly, which includes at least one of any of the aforementioned HBC solar cells. This battery component has the same or similar beneficial effects as the aforementioned HBC solar cell, and the relevant parts can be referred to each other. To avoid repetition, they will not be described again here.

The present application also provides a method for preparing an HBC solar cell. FIG. 5 shows a step flow chart of a method for preparing an HBC solar cell in an embodiment of the present application. Referring to Figure 5, the method includes the following steps:

Step S1, sequentially forming a first transmission layer, an insulating layer and an insulating protective layer for protecting the insulating layer on the backlight side of the silicon substrate; the insulating protective layer is distributed adjacent to the insulating layer, and the insulating protective layer Located on the side of the insulating layer away from the silicon substrate; under the same etching conditions, the etching rate of the insulating protective layer is less than the etching rate of the insulating layer

Figure 6 shows a partial structural diagram of the first HBC solar cell in the embodiment of the present application. As shown in Figure 6, 111 is the backlight surface of the silicon substrate 1, 222 is the light-facing surface of the silicon substrate 1, and they are relatively distributed. The first transmission layer 3 , the insulating layer 4 and the insulating protective layer 5 protecting the insulating layer 4 are sequentially formed on the backlight side of the silicon substrate 1 , so that the insulating protective layer 5 and the insulating layer 4 are closely adjacent to each other, and the insulating protective layer 5 Located on the side of the insulating layer 4 away from the silicon substrate 1 .

Under the same etching conditions, the etching rate of the insulating protective layer 5 is lower than the etching rate of the insulating layer 4. Furthermore, in the subsequent patterning process of each layer in the HBC solar cell, whether it is laser etching Whether it is acidic etching or alkaline etching, the etching rate of the insulating protective layer 5 is slow. The insulating protective layer 5 located on the side of the insulating layer 4 away from the silicon substrate will play a good protective role in the insulating layer 4, so that The insulating layer 4 will basically not be damaged or affected, which can improve the insulation performance of the HBC solar cell, basically avoiding the problem in the existing technology that the HBC preparation process is difficult to proceed smoothly, and also basically avoiding the problem of solar energy caused by the damage of the insulating layer 4. The problem of reduced battery efficiency.

It should be noted that the formation method of the first transmission layer 3, the insulating layer 4 and the insulating protective layer 5 protecting the insulating layer 4 is not specifically limited. For example, it can be formed by PECVD (Plasma Enhanced Chemical Vapor Deposition (Plasma Enhanced Chemical Vapor Deposition) forms the insulating layer 4 .

Step S2: Open an opening on the insulating protective layer so that the insulating layer is exposed.

Figure 7 shows a partial structural diagram of the second HBC solar cell in the embodiment of the present application. As shown in Figure 7, a laser is used to open an opening on the insulating protective layer 5, and the opening is 6, so that the insulating layer 4 is exposed.

Step S3: Remove the exposed portion of the insulating layer and the portion of the first transmission layer corresponding to the opening.

Figure 8 shows a partial structural diagram of the third HBC solar cell in the embodiment of the present application. As shown in Figure 8, the exposed portion of the insulating layer 4 is removed. Figure 9 shows a partial structural schematic diagram of the fourth HBC solar cell in the embodiment of the present application. As shown in FIG. 9 , the portion of the first transmission layer 3 corresponding to the opening 6 is removed. The portion corresponding to the opening 6 in the first transmission layer 3 can be removed by using at least one of three methods: laser, wet etching, or first covering the mask and then using wet etching. During the process of removing the part corresponding to the opening 6 in the first transmission layer 3, the insulating protective layer 5 located on the side of the insulating layer 4 away from the silicon substrate will play a good protective role in the insulating layer 4, so that the insulating layer 4 will basically not Being damaged or affected, the insulation performance of the HBC solar cell can be improved, which basically avoids the problem in the existing technology that the HBC preparation process is difficult to proceed smoothly, and also basically avoids the problem that the efficiency of the solar cell decreases due to the damage of the insulation layer 4 .

Step S4: Form a second transmission layer on the remaining insulating protective layer and the backlight side of the silicon substrate; the first transmission layer and the second transmission layer have different doping types.

Figure 10 shows a partial structural diagram of the fifth HBC solar cell in the embodiment of the present application. As shown in FIG. 10 , a second transmission layer 10 is formed on the remaining insulating protective layer 5 and the backlight side of the silicon substrate 1 . The first transmission layer 3 and the second transmission layer 10 have different doping types. The formation method of the second transmission layer 10 is not specifically limited. For example, it may be formed by deposition.

Optionally, the above-mentioned method of forming the insulating protective layer 5 may include: depositing the insulating protective layer 5 on the insulating layer 4. The process is mature and simple. For example, the insulating protective layer 5 is deposited by PECVD.

Figure 11 shows a partial structural schematic diagram of the sixth HBC solar cell in the embodiment of the present application. As shown in Figure 11, the above-mentioned formation of the insulating protective layer 5 may include: forming at least one P-type layer 52 on the insulating layer 4. The material of the P-type layer 52 is selected from: P-type amorphous silicon, P-type microcrystalline silicon. , P-type polysilicon, silicon oxide containing P-type doped materials, silicon carbide containing P-type doped materials, P-type doped materials Silicon nitride as an impurity material, at least one of six types; an intrinsic amorphous silicon layer 51 is formed on the above-mentioned P-type layer 52 . The above-mentioned opening on the insulating protective layer 5 includes: using the intrinsic amorphous silicon layer 51 as a laser absorption layer, opening the opening on the insulating protective layer 5 by laser, and the intrinsic amorphous silicon layer 51 as the laser absorbing layer can protect the lower layer. The laser is smaller, which can adjust the laser processing window, reduce the damage of the laser to the passivation layer, and increase the range of laser power, making it easier to achieve industrial production, and in the process of using laser etching , or during the wet etching process, the intrinsic amorphous silicon layer 51 can increase the corrosion resistance of the insulating protective layer 5, so that the protective effect on the insulating layer 4 is better. It should be noted that the intrinsic amorphous silicon layer 51 as the laser absorption layer can be removed during the subsequent patterning process of other layers, and the structure of the formed solar cell can be as shown in Figure 1 or Figure 2 . For example, the intrinsic amorphous silicon layer 51 as the laser absorption layer can be washed away in the subsequent alkali etching solution.

Optionally, as shown in FIGS. 2 and 4 , forming the insulating protective layer 5 includes: forming at least one P-type layer 52 and at least one intrinsic amorphous silicon layer 51 on the insulating layer 4 , and forming the insulating protective layer 5 The side of layer 5 away from the silicon substrate 1 is a P-type layer 52. The material of the P-type layer 52 is selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, and silicon containing P-type doped substances. Oxide, silicon carbide containing P-type doping material, silicon nitride containing P-type doping material, at least one of the six types. During the subsequent patterning process of each layer in the HBC solar cell, whether it is laser etching, acid etching or alkaline etching, the P-type layer 52 will protect the intrinsic amorphous silicon layer 51 from being affected. , thus making the insulating protective layer 5 have excellent performance, making the etching rate of the insulating protective layer 5 slower, and the insulating protective layer 5 located on the side of the insulating layer 4 away from the silicon substrate will play a good protective role in the insulating layer 4 , so that the insulating layer 4 will basically not be damaged or affected, which can improve the insulation performance of the HBC solar cell, basically avoiding the problem that the HBC preparation process is difficult to proceed smoothly in the existing technology, and also basically avoiding the damage of the insulating layer 4 A problem that causes the efficiency of solar cells to decrease. Moreover, the insulating protective layer 5 has a laminated structure. The interfaces between the various layers of the insulating protective layer 5 will reflect light. If the laser etching process is used for patterning preparation, the laser reaching the lower layer will be smaller, which can adjust the laser. The function of the processing window can reduce the damage of the laser to the passivation layer, and can increase the use range of the laser power, making it easier to achieve industrial production, and during the process of laser etching or wet etching, The laminated structure can increase the corrosion resistance of the insulating protective layer 5 and provide better protection for the insulating layer 4 .

Optionally, referring to FIG. 4 , forming the insulating protective layer may be: forming an insulating layer on the insulating layer. A first P-type layer 521 is formed, an intrinsic amorphous silicon layer 52 is formed on the first P-type layer 521 , and a second P-type layer 522 is formed on the intrinsic amorphous silicon layer 52 . During the subsequent patterning process of each layer in the HBC solar cell, whether it is laser etching, acid etching or alkaline etching, the second P-type layer 522 will protect the intrinsic amorphous silicon layer 51 from is affected, thereby making the insulating protective layer 5 have excellent performance, making the etching rate of the insulating protective layer 5 slower, and the insulating protective layer 5 located on the side of the insulating layer 4 away from the silicon substrate will play a good role in protecting the insulating layer 4 The protective effect prevents the insulating layer 4 from being damaged or affected, which can improve the insulation performance of the HBC solar cell and basically avoid the problem of the HBC preparation process being difficult to proceed smoothly in the existing technology. At the same time, it also basically avoids the problem that the insulating layer 4 Damage causes the efficiency of solar cells to decrease. Similarly, the insulating protective layer 5 has a laminated structure, and the interfaces between the various layers of the insulating protective layer 5 will reflect light. If the laser etching process is used for patterning preparation, the laser reaching the lower layer will be smaller, which can achieve Adjusting the role of the laser processing window can reduce the damage of the laser to the passivation layer, and can increase the use range of the laser power, making it easier to achieve industrial production, and use the laser etching process, or in the wet etching process , the stacked structure can increase the corrosion resistance of the insulating protective layer 5, making the protection of the insulating layer 4 better. At the same time, the first P-type layer 521 closest to the silicon substrate can also serve as the final barrier against etching, enhancing to protect the insulating layer 4.

Referring to FIG. 6 , before forming the first transmission layer 3 , the method may further include forming a first back passivation layer 2 on the backlight surface of the silicon substrate 1 . The first back passivation layer 2 may be formed on the first back passivation layer 2 . Layer 3. As shown in FIG. 9 , after removing the portion corresponding to the opening in the first transmission layer 3 or at the same time and before forming the second transmission layer 10 , the method may also include: removing the portion corresponding to the opening in the first back passivation layer 2 , so that The silicon substrate 1 is exposed. As shown in FIG. 10 , the method may further include: forming a second backside passivation layer 9 on the remaining insulating protective layer 5 and the exposed silicon substrate 1 . The aforementioned step S4 is: forming the second transmission layer 10 on the second backside passivation layer 9 .

As shown in FIG. 10 , the method may further include: forming a front passivation layer 11 , a front semiconductor layer 12 and a front anti-reflection layer 13 on the light-facing surface of the silicon substrate 1 . The doping type of the front semiconductor layer 12 may be the same as the doping type of the silicon substrate 1 . The material of the front passivation layer 11 may also be intrinsic amorphous silicon, and the thickness of the front passivation layer 11 may be 3-15 nm. The thickness of the front semiconductor layer 12 may be 3-20 nm, and the thickness of the front anti-reflection layer 13 may be 50-200 nm.

Figure 12 shows a partial structural diagram of the seventh HBC solar cell in the embodiment of the present application. As shown in Figure 12, the method may also include: sequentially removing part of the insulation in the second transmission layer 10 The area corresponding to layer 4 and the area corresponding to part of the insulating layer 4 in the second back surface passivation layer 9, so that in the direction in which the second back surface passivation layer 9 and the second transmission layer 10 are stacked, the second back surface passivation layer 9 and the second transmission layer 10 are The second transmission layer 10 is distributed evenly. Use a laser to remove part of the area corresponding to the insulating layer 4 in the insulating protective layer 5, so that in the direction in which the second back passivation layer 9 and the second transmission layer 10 are stacked, the insulating protective layer 5 and the second back passivation layer 9 are flush. distributed. In the process of removing the area corresponding to part of the insulating layer 4 in the second transmission layer 10 and the area corresponding to part of the insulating layer 4 in the second back surface passivation layer 9, the insulating protective layer 5 will play a good protective role on the insulating layer 4. , so that the insulation layer 4 is basically not damaged or affected, which can improve the insulation performance of the HBC solar cell.

It should be noted that in FIG. 12 , the area corresponding to part of the insulating layer 4 in the second transmission layer 10 is removed, the area corresponding to part of the insulating layer 4 in the second back passivation layer 9 is removed, and the area corresponding to part of the insulating layer 4 in the insulating protection layer 5 is removed. The area can be removed with laser or laser absorption plus laser in one go. Alternatively, use wet etching or mask-humidified etching to remove part of the area corresponding to the insulating layer 4 in the second transmission layer 10 and part of the area corresponding to the insulating layer 4 in the second back passivation layer 9 at one time, and then remove the A laser is used to remove the area corresponding to part of the insulating layer 4 in the insulating protective layer 5 . In the embodiments of this application, there is no specific limitation on this.

Figure 13 shows a partial structural diagram of the eighth HBC solar cell in the embodiment of the present application. Referring to FIG. 13 , the method may further include: removing part of the insulating layer 4 so that in the direction in which the second backside passivation layer 9 and the second transmission layer 10 are stacked, the insulating protective layer 5 and the insulating layer 4 are evenly distributed, And the first transmission layer 3 is exposed. An acidic etching solution may be used to remove part of the insulating layer 4 .

Figure 14 shows a partial structural diagram of the ninth HBC solar cell in the embodiment of the present application. Referring to FIG. 14 , the method may further include: forming a transparent conductive layer 16 on the exposed first transmission layer 3 and the remaining second transmission layer 10 . The transparent conductive layer 16 can be formed using PVD (Physical Vapor Deposition). Figure 15 shows a partial structural diagram of the tenth HBC solar cell in the embodiment of the present application. Referring to FIG. 15 , the remaining portion of the transparent conductive layer 16 is interrupted in the area corresponding to the insulating layer 4 . 17 in FIG. 15 is the interrupted area, which can avoid short circuit and has a good insulation effect. The remaining portion of the transparent conductive layer 16 corresponding to the insulating layer 4 may be completely interrupted or partially interrupted. In the embodiment of the present application, this is not specifically limited. The remaining portion of the transparent conductive layer 16 corresponding to the insulating layer 4 can be interrupted by laser interruption or mask humidification etching. In the embodiment of the present application, this is not specifically limited. Then, a non-interrupted area is formed on the transparent conductive layer 16 electrode. As shown in Figures 1 to 4, specifically, the first electrode 18 is formed on the transparent conductive layer 16 in the area corresponding to the first transmission layer 3, and the second electrode 19 is formed in the area corresponding to the second transmission layer 10 on the transparent conductive layer 16. . The first electrode 18 and the second electrode 19 can be formed by screen printing or electroplating, which are not specifically limited in the embodiments of the present application. For example, conductive silver material is screen-printed and solidified to form silver electrodes.

It should be noted that HBC solar cells, HBC solar cell preparation methods, and battery components can be mutually referenced and can achieve the same or similar beneficial effects. In order to avoid duplication, the relevant parts will not be described again.

Examples are listed below to further explain this application.

Example 1

Referring to FIG. 7 , the silicon substrate 1 may be an N-type silicon substrate, and the first backside passivation layer 2 may be an intrinsic amorphous silicon layer. The first transmission layer 3 can be an N-type amorphous silicon layer, and the insulating protective layer 5 can be a boron-doped amorphous silicon layer. A laser can be used to etch away part of the insulating protective layer 5 to form the opening 6 . Referring to FIG. 8 , an acidic solution can be used to remove the portion corresponding to the opening in the insulating layer 4 . Referring to Figure 9, an alkaline solution is used to remove the portion corresponding to the opening 6 in the first transmission layer 3 and the portion corresponding to the opening 6 in the first back passivation layer 2, and an acidic solution is used to remove the portion corresponding to the opening 6 on the silicon substrate 1. Natural oxide layer. In Figure 9, an alkaline solution is used to remove the portion corresponding to the opening 6 in the first transmission layer 3 and the portion corresponding to the opening 6 in the first back passivation layer 2, and an acidic solution is used to remove the natural oxidation on the silicon substrate 1 corresponding to the opening 6. During the entire process, the insulating protective layer 5, that is, the boron-doped silicon oxide layer, will play a good protective role in the insulating layer 4. At the same time, as shown in Figure 1, the insulating protective layer 5 will remain in the final solar cell. . The second transmission layer 10 in Figure 1 may be a P-type amorphous silicon layer. The front semiconductor layer 12 may be an N-type amorphous silicon layer. The front anti-reflection layer 13 may be silicon nitride or silicon oxide.

Example 2

Referring to Figure 2, what is different from Embodiment 1 is that the insulating protective layer 5 in Embodiment 2 has a laminated structure. Compared with Embodiment 1, the interfaces between the various layers of the insulating protective layer 5 will reflect light. If the laser etching process is used for patterning preparation, the laser reaching the lower layer will be smaller, which can adjust the laser processing window, reduce the damage of the laser to the passivation layer, and increase the use range of the laser power. It is easier to realize industrial production, and during the process of laser etching or wet etching, the laminated structure can increase the corrosion resistance of the insulating protective layer 5, making the protective effect of the insulating layer 4 better.

Example 3

Referring to Figures 3 and 11, what is different from Embodiment 1 is that in Figure 11, the intrinsic amorphous silicon layer 51 is used as a laser absorption layer, and an opening is opened on the insulating protective layer 5 by laser to serve as the intrinsic laser absorption layer. The amorphous silicon layer 51 can protect the laser that reaches the lower layer from being smaller, can adjust the laser processing window, reduce the damage of the laser to the passivation layer, and can increase the use range of laser power, making it easier to realize industrial production. , and during the process of laser etching or wet etching, the intrinsic amorphous silicon layer 51 can increase the corrosion resistance of the insulating protective layer 5, so that the protective effect on the insulating layer 4 is better. The intrinsic amorphous silicon layer 51 as the laser absorption layer can be washed away in the subsequent alkali etching solution to obtain the HBC solar cell shown in Figure 3. Although the structure of the HBC solar cell shown in Figure 3 and the HBC solar cell shown in Figure 1 are basically the same, the solar cell shown in Figure 3, as shown in Figure 11, is used in the process of preparing the insulating protective layer 5. The amorphous silicon layer 51 serves as a laser absorption layer, and therefore has the aforementioned beneficial effects of the laser absorption layer.

Example 4

Referring to FIG. 4 , what is different from Embodiment 1 is that the insulating protective layer 5 in Embodiment 4 also has a stacked structure. Specifically, the insulating protective layer 5 consists of a first P-type layer 521 , an intrinsic amorphous layer 521 , and an intrinsic amorphous layer 521 . It is composed of silicon layer 51 and second P-type layer 522. Compared with Embodiment 1, the interfaces between the various layers of the insulating protective layer 5 will reflect light. If a laser etching process is used for patterning preparation, the laser light reaching the lower layer will be smaller, which can adjust the laser processing window. It can reduce the damage of laser to the passivation layer, and can increase the range of laser power, making it easier to achieve industrial production. In addition, during the process of laser etching or wet etching, the stacking The structure can increase the corrosion resistance of the insulating protective layer 5, making the protection of the insulating layer 4 better. At the same time, the first P-type layer 521 closest to the silicon substrate can also serve as the final barrier against etching, enhancing the protection of the insulating layer. 4 protective effect.

It should be noted that for the sake of simple description, the method embodiments are expressed as a series of action combinations. However, those skilled in the art should know that the embodiments of the present application are not limited by the described action sequence, because According to the embodiments of the present application, certain steps may be performed in other orders or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily necessary for the embodiments of the present application.

It should be noted that, in this document, the terms "comprising", "comprises" or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article or device that includes a series of elements not only includes those elements, and also includes other elements not explicitly listed, or Also included are elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article or apparatus that includes that element.

Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus the necessary general hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is better. implementation. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product in essence or that contributes to the existing technology. The computer software product is stored in a storage medium (such as ROM/RAM, disk, CD), including several instructions to cause a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in various embodiments of this application.

The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above-mentioned specific implementations. The above-mentioned specific implementations are only illustrative and not restrictive. Those of ordinary skill in the art will Inspired by this application, many forms can be made without departing from the purpose of this application and the scope protected by the claims, and these all fall within the protection of this application.

Claims (18)

1. An HBC solar cell, including:

   A silicon substrate, a first transmission layer, a second transmission layer, an insulating layer, and an insulating protective layer for protecting the insulating layer, all located on the backlight side of the silicon substrate; the first transmission layer and the second transmission layer Different doping types;

   The first projection of the second transmission layer on the backlight surface of the silicon substrate and the second projection of the first transmission layer on the backlight surface of the silicon substrate have overlapping areas and non-overlapping areas; The insulating layer and the insulating protective layer are both located between the first transmission layer and the second transmission layer and completely cover the overlapping area; the insulating protective layer and the insulating layer are distributed adjacent to each other, and the insulating protective layer A layer is located on a side of the insulating layer away from the silicon substrate;

   Under the same etching conditions, the etching rate of the insulating protective layer is lower than the etching rate of the insulating layer.
2. The HBC solar cell according to claim 1, wherein under the same alkali etching conditions, the etching rate of the insulating layer is 30-1800 times that of the insulating protective layer.
3. The HBC solar cell according to claim 2, wherein under alkali etching conditions of 50-150°C and a mass concentration of an alkali etching solution of 0.1%-1.2%: the etching rate of the insulating layer is 300-300%. 1800nm/min, and the etching rate of the insulating protective layer is 1-10nm/min.
4. The HBC solar cell according to any one of claims 1 to 3, wherein the material of the insulating protective layer is selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polycrystalline silicon, P-type doped substances. Silicon oxide, silicon carbide containing P-type doping material, silicon nitride containing P-type doping material, at least one of the six types.
5. The HBC solar cell according to claim 4, wherein the insulating protective layer has a single-layer structure or a stacked structure.
6. The HBC solar cell according to claim 4, wherein the thickness of the insulating protective layer is 1 nm-2um; the thickness of the insulating protective layer is: the thickness of the insulating protective layer is between the silicon substrate and the insulating layer. Dimensions in stacking direction.
7. The HBC solar cell according to any one of claims 1 to 3, wherein the insulating protective layer includes at least one P-type layer and at least one intrinsic amorphous silicon layer, and the insulating protective layer is far away from the One side of the silicon substrate is a P-type layer;

   The material of the P-type layer is selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, P-containing At least one of six types: silicon oxide containing P-type doping material, silicon carbide containing P-type doping material, and silicon nitride containing P-type doping material.
8. The HBC solar cell according to claim 7, wherein the insulating protective layer is composed of a first P-type layer, an intrinsic amorphous silicon layer, and a second P-type layer stacked in sequence; or, the insulating protective layer is composed of It is composed of a stacked third P-type layer and an intrinsic amorphous silicon layer.
9. The HBC solar cell according to any one of claims 1 to 3, wherein the insulating protective layer includes: at least one of a boron-doped silicon oxide layer, a boron-doped silicon carbide layer, and a boron-doped silicon nitride layer. .
10. The HBC solar cell according to any one of claims 1 to 3, wherein the material of the insulating layer is selected from: silicon nitride and/or silicon oxide.
11. The HBC solar cell according to any one of claims 1 to 3, wherein the HBC solar cell further includes: a first back passivation layer, a second back passivation layer and a second back passivation layer located on the same side of the silicon substrate as the insulating layer. Backside passivation layer, transparent conductive layer, first electrode and second electrode;

    The first back passivation layer and the first transmission layer are both located between the silicon substrate and the insulating layer, and the first transmission layer is located away from the first back passivation layer and the silicon substrate. one side; the second projection of the first transmission layer on the silicon substrate overlaps with the third projection of the first back passivation layer on the silicon substrate; the first back passivation layer Distributed intermittently on the silicon substrate;

    The second backside passivation layer includes a flush portion distributed flush with the first backside passivation layer, the flush portion is located at an interrupted position of the first backside passivation layer, and is flush with the first backside passivation layer. The backside passivation layer forms an entire layer covering the silicon substrate;

    The second backside passivation layer, the second transmission layer, and the transparent conductive layer are sequentially stacked on the side of the insulating protective layer away from the silicon substrate; the transparent conductive layer is not placed on the overlapping area. continuous;

    The first electrode and the second electrode are both located at positions corresponding to the non-overlapping areas on the transparent conductive layer, and the first electrode corresponds to the first transmission layer, and the second electrode and The second transport layer position corresponds.
12. A battery component, comprising: at least one HBC solar cell according to any one of claims 1-11.
13. A method for preparing HBC solar cells, which includes:

    A first transmission layer, an insulating layer and a layer for protecting the insulating layer are sequentially formed on the backlight side of the silicon substrate. layer of insulating protective layer; under the same etching conditions, the etching rate of the insulating protective layer is less than the etching rate of the insulating layer;

    Use a laser to open the insulating protective layer so that the insulating layer is exposed;

    Remove the exposed portion of the insulating layer and the portion of the first transmission layer corresponding to the opening;

    A second transmission layer is formed on the remaining insulating protective layer and the backlight side of the silicon substrate; the first transmission layer and the second transmission layer have different doping types.
14. The method for preparing an HBC solar cell according to claim 13, wherein forming the insulating protective layer includes:

    The insulating protective layer is deposited on the insulating layer.
15. The method for preparing an HBC solar cell according to claim 13 or 14, wherein forming the insulating protective layer includes:

    At least one P-type layer is formed on the insulating layer; the material of the P-type layer is selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, and silicon oxide containing P-type doping substances. , silicon carbide containing P-type doping material, silicon nitride containing P-type doping material, at least one of the six types;

    The method of using a laser to open an opening on the insulating protective layer includes:

    forming an intrinsic amorphous silicon layer on the P-type layer;

    The intrinsic amorphous silicon layer is used as a laser absorption layer, and a laser is used to make openings on the insulating protective layer.
16. The method for preparing an HBC solar cell according to claim 13 or 14, wherein forming the insulating protective layer includes:

    At least one P-type layer and at least one intrinsic amorphous silicon layer are formed on the insulating layer, and the side of the insulating protective layer away from the silicon substrate is a P-type layer; Materials are selected from: P-type amorphous silicon, P-type microcrystalline silicon, P-type polysilicon, silicon oxide containing P-type doped substances, silicon carbide containing P-type doped substances, silicon containing P-type doped substances Nitride, at least one of six species.
17. The method for preparing an HBC solar cell according to claim 16, wherein forming the insulating protective layer includes:

    forming a first P-type layer on the insulating layer;

    forming an intrinsic amorphous silicon layer on the first P-type layer;

    A second P-type layer is formed on the intrinsic amorphous silicon layer.
18. The method for preparing an HBC solar cell according to claim 13 or 14, wherein before forming the first transmission layer, the method further includes:

    Forming a first backside passivation layer on the backlight surface of the silicon substrate;

    The forming the first transmission layer includes: forming the first transmission layer on the first backside passivation layer;

    After removing the portion of the first transmission layer corresponding to the opening and before forming the second transmission layer, the method further includes:

    Remove the portion of the first back passivation layer corresponding to the opening so that the silicon substrate is exposed;

    Form a second backside passivation layer on the remaining insulating protective layer and the exposed silicon substrate;

    The forming the second transmission layer includes:

    forming the second transmission layer on the second backside passivation layer;

    The method also includes:

    Part of the area corresponding to the insulating layer in the second transmission layer and part of the area corresponding to the insulating layer in the second back surface passivation layer are sequentially removed, so that there is no gap between the second back surface passivation layer and the third back surface passivation layer. In the direction in which the two transmission layers are stacked, the second backside passivation layer and the second transmission layer are evenly distributed;

    Use a laser to remove part of the area corresponding to the insulating layer in the insulating protective layer, so that in the direction in which the second backside passivation layer and the second transmission layer are stacked, the insulating protective layer and the second The backside passivation layer is distributed evenly.