阅读说明：本技术 一种清洗器和提高异质结太阳电池转换效率的方法 (Cleaner and method for improving conversion efficiency of heterojunction solar cell ) 是由 孙林 杜俊霖 陈功兵 张�林 杨秀清 刘香飞 闫涛 潘登 于 2021-08-17 设计创作，主要内容包括：一种清洗器和提高异质结太阳电池转换效率的方法,属于太阳电池领域。提高异质结太阳电池转换效率的方法包括于制作异质结太阳电池时,在对异质结太阳电池的单晶硅片制绒之后、以及制作非晶硅层之前,实施以下去有机物操作：使用紫外线照射,用以对制绒后的单晶硅片进行清洗的清洗液和/或清洗槽,以对应使清洗液和/或清洗槽中的有机物污染物通过光化学反应被分解而去除或减少。该方案可以提高异质结太阳电池的转换效率。(A cleaner and a method for improving the conversion efficiency of a heterojunction solar cell belong to the field of solar cells. The method for improving the conversion efficiency of the heterojunction solar cell comprises the following operations of removing organic matters after texturing a monocrystalline silicon wafer of the heterojunction solar cell and before manufacturing an amorphous silicon layer when the heterojunction solar cell is manufactured: and the cleaning solution and/or the cleaning tank are used for cleaning the textured monocrystalline silicon wafer by using ultraviolet irradiation, so that organic pollutants in the cleaning solution and/or the cleaning tank are decomposed through a photochemical reaction and removed or reduced. The scheme can improve the conversion efficiency of the heterojunction solar cell.)

1. A method for improving the conversion efficiency of a heterojunction solar cell, wherein the heterojunction solar cell comprises a monocrystalline silicon layer and amorphous silicon layers respectively formed on two sides of the monocrystalline silicon layer, and the method comprises the following organic matter removing operations by ultraviolet rays after texturing a monocrystalline silicon wafer and before manufacturing the amorphous silicon layer when manufacturing the heterojunction solar cell:

and the cleaning solution and/or the cleaning tank are used for cleaning the textured monocrystalline silicon wafer by using ultraviolet irradiation, so that organic pollutants in the cleaning solution and/or the cleaning tank are decomposed through a photochemical reaction and removed or reduced.

2. The method for improving the conversion efficiency of the heterojunction solar cell of claim 1, wherein the organic matter removing operation is performed before the texturized monocrystalline silicon wafer enters the cleaning tank;

alternatively, the organic matter removing operation is performed before or during the cleaning solution enters the cleaning tank.

3. A method for improving the conversion efficiency of a heterojunction solar cell according to claim 1 or 2, wherein the irradiation with ultraviolet light is performed continuously;

alternatively, the irradiation with ultraviolet rays is performed intermittently.

4. The method of claim 3, wherein the irradiation with ultraviolet light is performed intermittently at a fixed frequency.

5. The method of claim 1, wherein the ultraviolet light has a wavelength of 185 nm.

6. The method of claim 1 or 5, wherein the organic removal operation increases minority carrier lifetime in the heterojunction solar cell.

7. A washer for implementing the method of improving the conversion efficiency of a heterojunction solar cell according to any of claims 1 to 6, characterized in that it comprises:

the groove body is provided with a bottom wall and a side wall, and a groove cavity defined with a depth direction is formed by enclosing together;

a liquid inlet joint arranged on the bottom wall or the side wall and close to the bottom wall and configured to provide cleaning liquid for the groove cavity along a direction criss-cross with the depth direction;

an ultraviolet generating mechanism held by the tank body and configured to emit ultraviolet rays toward the inside of the tank cavity.

8. The washer according to claim 7, wherein said tank chamber is open; or, the slot cavity is closed, and the cleaner further comprises a cover body which is matched with the side wall of the slot body to close the slot cavity.

9. The cleaning apparatus as claimed in claim 8, wherein the cover has an overflow joint for allowing the cleaning liquid in the tank chamber to flow out of the tank chamber;

or the cover body is detachably connected with the side wall;

alternatively, the ultraviolet generating mechanism is fixed to the cover.

10. The cleaning device according to any one of claims 7 to 9, wherein the ultraviolet generating mechanism is fixed to the bottom wall and/or the side wall;

or the cleaner also comprises a switch electrically connected with the ultraviolet generating mechanism and used for selectively switching on or off the connection between the ultraviolet generating mechanism and the power supply;

or, the ultraviolet lamp further comprises a switch and a frequency generating mechanism, wherein the switch is electrically connected with the ultraviolet generating mechanism through the frequency generating mechanism, and the frequency generating mechanism is used for generating an on-off signal with a set fixed frequency so as to enable the switch and the ultraviolet generating mechanism to be electrically connected with each other at the fixed frequency for switching on or switching off.

Technical Field

The application relates to the field of solar cells, in particular to a cleaner and a method for improving conversion efficiency of a heterojunction solar cell.

Background

Power generation efficiency and power generation cost are important propositions for the photovoltaic industry.

The power generation efficiency includes conversion efficiency and stability thereof. The conversion efficiency is related to the conversion efficiency of a single battery piece and the packaging technology of the assembly. Among the various heterojunction cells, the cells having relatively high conversion efficiency are, for example, heterojunction cells.

How to optimize to further optimize the conversion efficiency of the heterojunction cell is a challenge.

Disclosure of Invention

The present application provides a cleaner and a method for improving the conversion efficiency of a heterojunction solar cell, which can partially or completely improve or even solve the problem of the conversion efficiency of the heterojunction solar cell in the related art.

The application is realized as follows:

in a first aspect, examples of the present application provide a method of improving the conversion efficiency of a heterojunction solar cell comprising a single-crystal silicon layer and amorphous silicon layers on either side thereof.

The method comprises performing the following organic matter removing operation by using ultraviolet rays after texturing a monocrystalline silicon wafer and before forming an amorphous silicon layer when manufacturing the heterojunction solar cell:

and the cleaning solution and/or the cleaning tank are used for cleaning the textured monocrystalline silicon wafer by using ultraviolet irradiation, so that organic pollutants in the cleaning solution and/or the cleaning tank are decomposed through a photochemical reaction and removed or reduced.

According to some examples of the present application, the organic matter removing operation is performed before the textured single crystal silicon wafer enters the cleaning tank; alternatively, the organic removal operation is performed before or during the cleaning solution entering the cleaning tank.

According to some examples of the application, the irradiating with ultraviolet light is performed continuously; alternatively, irradiation with ultraviolet rays is performed intermittently.

According to some examples of the application, the irradiation with ultraviolet light is performed intermittently at a fixed frequency.

According to some examples of the application, the wavelength of the ultraviolet light is 185 nm.

According to some examples of the present application, the de-organics operation increases minority carrier lifetime in the heterojunction solar cell.

In a second aspect, examples of the present application provide a cleaner for implementing the above-described method of improving the conversion efficiency of a heterojunction solar cell.

The washer includes:

the groove body is provided with a bottom wall and a side wall, and a groove cavity defined with a depth direction is formed by enclosing together;

the liquid inlet joint is arranged on the bottom wall or the side wall and close to the bottom wall, and is configured to provide cleaning liquid for the groove cavity along the direction which is criss-cross with the depth direction;

an ultraviolet generating mechanism held in the tank body and configured to emit ultraviolet rays toward the inside of the tank cavity.

According to some examples of the application, the slot cavity is open; or the groove cavity is closed, and the cleaner further comprises a cover body which is matched with the side wall of the groove body to close the groove cavity.

According to some examples of the application, the cover body is provided with an overflow joint for enabling the cleaning liquid in the groove cavity to flow out of the groove cavity; or the cover body is detachably connected with the side wall; alternatively, the ultraviolet generating mechanism is fixed to the lid.

According to some examples of the present application, an ultraviolet light generating mechanism is fixed to the bottom wall and/or the side wall;

or the cleaner also comprises a switch electrically connected with the ultraviolet generating mechanism and used for selectively switching on or off the connection between the ultraviolet generating mechanism and the power supply;

or the ultraviolet lamp further comprises a switch and a frequency generating mechanism, wherein the switch is electrically connected with the ultraviolet generating mechanism through the frequency generating mechanism, and the frequency generating mechanism is used for generating an on-off signal with a set fixed frequency so as to enable the switch and the ultraviolet generating mechanism to be electrically connected with each other at the fixed frequency or to be switched off.

In the implementation process, the method and the device provided by the embodiment of the application provide a cleaning environment without organic pollutants or less inorganic pollutants for the cleaning process of the textured monocrystalline silicon wafer, so that the degree of pollution or contamination of the textured monocrystalline silicon wafer by the organic pollutants is avoided or reduced, the quality (such as few defects, high interface quality and the like) of the amorphous silicon layer manufactured on the basis of the textured and clear monocrystalline silicon wafer is improved, and the electrical performance of the battery, such as conversion efficiency, is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments or the prior art of the present application, the drawings used in the description of the embodiments or the prior art will be briefly described below.

Fig. 1 is a schematic structural diagram of a silicon heterojunction solar cell fabricated in an embodiment of the present application;

FIG. 2 is a graph showing the tendency of change in resistivity and minority carrier lifetime of pure water for cleaning a silicon wafer irradiated with ultraviolet rays in the example of the present application;

fig. 3 shows a schematic structural diagram of a cleaner for implementing the method for improving the conversion efficiency of the heterojunction solar cell in the example of the application.

Icon: 110-surface silver electrode; 111-surface transparent conductive oxide; 112-surface N + doped amorphous silicon; 113-surface intrinsic amorphous silicon; 114-backside intrinsic amorphous silicon; 115-backside P + doped amorphous silicon; 116-backside transparent conductive oxide; 117 — back silver electrode; 201-a trough body; 2011-side wall; 2012-bottom wall; 202-ultraviolet generating mechanism.

Detailed Description

The general structure of a heterojunction solar cell can be seen in figure 1. The heterojunction solar cell shown in the figure is based on N-type single crystal silicon, and heterojunctions made of amorphous layers are formed on both sides of the single crystal silicon as a substrate, respectively, and a double-sided cell structure is formed.

From the direction shown in fig. 1, there are a surface silver electrode 110, a surface transparent conductive oxide 111, a surface N + doped amorphous silicon 112, a surface intrinsic amorphous silicon 113, an N doped monocrystalline silicon (i.e., N-type monocrystalline silicon), a back intrinsic amorphous silicon 114, a back P + doped amorphous silicon 115, a back transparent conductive oxide 116 and a back silver electrode 117 from top to bottom.

In the conventional process for fabricating a heterojunction solar cell, for example, the following steps are performed: texturing, amorphous silicon, TCO, screen printing of electrodes and testing.

The texturing process is, for example, roughly: pre-cleaning, damage removal, SC1(Standard Clean1), texturing, SC1(Standard Clean1), CP (Chemical Polish), HF cleaning (using dilute hydrofluoric acid DHF), and baking were performed in this order.

More specifically, the texturing process is substantially as follows: the method comprises the following steps of pre-cleaning, water tank, removing damage, water tank, SC1, water tank, texturing, water tank, SC1, water tank, CP, water tank, HF tank, water tank and drying.

One of the main purposes of texturing is to remove the smudge and damage layer from the surface of the silicon wafer and to form a surface texture. As known to the inventors of the present application, in the current heterojunction solar cell, an N-type silicon wafer is subjected to alkali texturing to form pyramids on the surface of the silicon wafer, and after texturing, organic matter on the surface is cleaned, and chemical polishing is performed.

Among these, the cleaning step after the texturing is generally a so-called "post-cleaning" and the first step of the post-cleaning step is generally performed with SC 1. The practical inventor finds that the operation carried out after the texturing, namely the post-cleaning, can influence the conversion efficiency of the heterojunction solar cell prepared based on the operation to a certain extent. As a result of the study, the inventors considered that one possible cause thereof was that organic contamination occurred in the post-cleaning operation. For example, additives on the surface of silicon wafers are organic, and these organic materials are not cleaned or have organic contamination in the subsequent cleaning process. Then, when the amorphous silicon coating is subsequently performed, the organic contaminants on the surface of the silicon wafer will seriously affect the interface performance thereof, thereby forming defects and finally affecting (deteriorating) the conversion efficiency of the cell.

Therefore, in the texturing process of the manufacturing flow of the heterojunction solar cell, after the SC1 and the subsequent process tanks, especially after CP (chemical polishing tank), if there is organic adhesion, the subsequent tanks will not have the capability of cleaning the organic.

Moreover, when the pure water station used in the battery manufacturing process is in a separate factory, the pure water needs to be transported to the workshop for use by a pipeline during the production, and the transportation pipeline is long (for example, 100-. Even if a small amount of pollution is brought into a groove body in the post-cleaning step, organic matter pollution can be caused to the surface of the silicon wafer, so that the coating passivation of amorphous silicon is influenced, and the conversion efficiency of the battery is finally influenced.

In view of such problems and analytical studies, the inventors propose a solution (which at least alleviates the above problems) and have verified that by eliminating or reducing organic contamination, the amorphous silicon minority carrier lifetime/the amorphous silicon minority carrier lifetime fluctuation of the heterojunction solar cell can be stabilized, and accordingly the conversion efficiency of the cell can also be stabilized (improved or at least not deteriorated).

According to the above analysis, organic contamination may be introduced mainly because pure water is contaminated, and such contaminants may also adhere to various cleaning tanks. One measure of the Organic content in water is the total Organic carbon, TOC (Total Organic carbon); which characterizes the organic content of pure water. Therefore, irradiation of pure water or a facility tank by an ultraviolet lamp is selected in the present example. Since ultraviolet rays are high-energy rays, organic substances in pure water are decomposed into water and carbon dioxide after ultraviolet irradiation, and carbon dioxide lowers the resistivity of pure water in water (increases the conductance).

Then, if the resistivity of pure water is significantly lowered under the irradiation of the ultraviolet lamp, it indicates that the TOC content in pure water before the irradiation is high. And at the same time, it is also known that organic contaminants in pure water can be removed by ultraviolet irradiation.

The reason why the ultraviolet lamp irradiation is adopted in the present example is that:

heterojunction solar cells are very sensitive to the organic content in pure water in the post-cleaning step of cleaning texturing. When the organic content in the pure water exceeds 20ppb, the amorphous silicon is adversely affected by minority carriers, thereby negatively affecting the final efficiency.

And the ultraviolet rays irradiate the pure water, so that the organic matters in the pure water are decomposed, and the content of the organic matters in the pure water is reduced. Therefore, the irradiation of ultraviolet rays can remove organic contamination, thereby reducing adverse effects on the battery. As shown in FIG. 2, the minority carrier lifetime after texturing was improved from 72. mu.s and 73. mu.s to 90. mu.s and 102. mu.s. And the minority carrier lifetime can be improved from 1500 mus to 2000 mus to 1700 mus to 2200 mus after the subsequent manufacture of the amorphous silicon.

Ultraviolet irradiation/cleaning is mainly achieved by the photosensitive oxidation of organic compounds to remove these organic substances. For example, the ultraviolet rays may employ a UV light source that emits light waves having wavelengths of 185nm and 254 nm. Ultraviolet rays having such a wavelength have high energy, and when these photons act on organic substances, most of hydrocarbons have strong absorption energy for ultraviolet rays having a wavelength of 185nm, and are decomposed into ions, free atoms, excited molecules, and neutrons after absorbing the energy of ultraviolet rays having a wavelength of 185nm, so that a so-called photosensitization occurs. Therefore, the organic matters in the pure water are decomposed through the photosensitive action, and the aim of reducing the content of the organic matter impurities in the pure water can be achieved. Based on this, the cleaning step of "water tank, CP, water tank, HF tank, water tank" may be selected to remove organic contaminants by ultraviolet irradiation.

In brief, referring to fig. 2, when ultraviolet rays are irradiated to pure water during the fabrication of the heterojunction solar cell, if the resistivity of the pure water decreases, it is indicated that organic contaminants exist in the pure water. These ultraviolet radiation can remove organic materials and correspondingly increase the minority carrier lifetime of the battery. Therefore, the irradiation of ultraviolet rays to pure water not only serves to detect the presence or absence of organic impurities in pure water, but also decomposes the organic impurities in the case where they are present.

Based on the above recognition, in examples of the present disclosure, the inventors propose a method that can be used to improve the heterojunction solar cell conversion efficiency. And the method is mainly implemented in a mode of reducing organic pollution in the manufacturing process of the heterojunction solar cell. In addition, based on the foregoing analysis, the inventors believe that the removal of organic contaminants can be primarily focused on post-cleaning operations after the texturing of the silicon wafer.

Therefore, the scheme in the example includes, in fabricating a heterojunction solar cell (the heterojunction solar cell includes a single-crystal silicon layer and amorphous silicon layers formed on both sides thereof, respectively), performing the following organic matter removing operation using ultraviolet rays after texturing a single-crystal silicon wafer and before fabricating the amorphous silicon layers: and a cleaning solution and/or a cleaning tank for cleaning the textured monocrystalline silicon wafer by irradiation with ultraviolet rays (for example, with a wavelength selected to be 185nm) so as to remove or reduce organic contaminants in the cleaning solution and/or the cleaning tank by decomposition through a photochemical reaction.

Wherein, the organic matter removing operation by ultraviolet rays may be performed before the texturized single crystal silicon wafer enters the cleaning tank, or before or during the cleaning solution enters the cleaning tank, as needed or according to the difficulty of modification of the apparatus or consideration of the cost. This is not specifically limited in this application.

In addition, various alternatives for the ultraviolet irradiation are also possible. For example, the ultraviolet rays may be irradiated to the water body or the tank body in a relatively stationary manner, or the ultraviolet rays may be irradiated to the water body or the tank body in a relatively moving manner. In these examples, the washer may be provided with a displacement mechanism for driving the ultraviolet generating mechanism to move.

In other examples, when ultraviolet irradiation is used, the ultraviolet irradiation may be performed by continuous irradiation, or the ultraviolet irradiation may be performed by intermittent irradiation. For example, the ultraviolet light may be irradiated all the way through the silicon wafer during the SC1 cleaning operation, or the ultraviolet light may be irradiated for a period of time, then the irradiation may be suspended for a period of time, and then the irradiation may be continued. Further, in the intermittent irradiation scheme, the ultraviolet irradiation may be performed intermittently at a fixed frequency.

In order to implement the above-mentioned organic matter removing operation, a cleaning device for implementing the method for improving the conversion efficiency of the heterojunction solar cell is also provided in the example, and the structure of the cleaning device is shown in fig. 3.

The cleaner includes a tank 201, a liquid inlet joint (not shown) and an ultraviolet ray generating mechanism 202. The tank 201 is a structure for receiving a cleaning liquid supplied from the liquid inlet joint and allowing the silicon wafer to be cleaned therein. And the ultraviolet ray generating mechanism 202 is used for introducing ultraviolet rays into the tank body 201 so as to carry out organic pollutant removal on equipment of the tank body 201, which may contact with the silicon wafer or attach organic pollutants to pollute the inner wall of the silicon wafer and/or cleaning liquid therein.

The housing 201 has a bottom wall 2012 and a side wall 2011 which enclose and form a cavity defining a depth direction. During a cleaning operation, a cleaning fluid is contained within the chamber, and the wafer is held within the chamber, possibly in contact with the bottom wall 2012 or the sidewalls 2011. The housing 201 may be an open channel structure or may have a closable channel structure. Thus, in an example where the tank 201 may be closed, the washer has a lid (not shown). The cover can mate with the sidewall 2011 of the housing 201 to enclose the housing. In addition, the cover may be rotatably connected to the side wall 2011 of the housing 201 through a rotating shaft, or may be detachably (e.g., snap) connected to the side wall 2011 of the housing 201.

When the silicon wafer is cleaned, liquid (cleaning liquid) can be introduced from the bottom of the tank body 201 optionally, and then the liquid can flow out from the opening at the top of the tank body in an overflow mode. Thus, by continuously introducing the cleaning liquid, the silicon wafers in the tank 201 can continuously contact the relatively cleaner cleaning liquid during cleaning.

Wherein, the liquid inlet joint is a component for injecting cleaning liquid into the groove cavity of the groove body 201. This may be done by providing a through hole in the bottom wall 2012 of the housing 201, or by providing a through hole in the side wall 2011 proximate to the bottom wall 2012. Further, in some examples, the liquid inlet joint may be implemented by a metal joint (welded or screwed) connected to the tank 201. In such a solution, the pipe for supplying the cleaning liquid may be connected to the metal joint.

In addition, the arrangement and the extension direction of the cleaning liquid conveying channel of the liquid inlet joint can be distributed along the direction criss-cross with the depth direction of the groove body. For example, the channel cavity of the tank body 201 is distributed in the vertical direction, and the conveying channel of the liquid inlet joint is conveyed along the horizontal direction. In this way, the cleaning liquid can convey the liquid in a direction substantially parallel to the bottom of the tank body 201, and at the same time, the liquid gradually accumulates in the tank cavity, and the water level gradually rises. As the water level rises, the cleaning liquid eventually overflows from the opening of the tank body 201 (or, in some examples, an overflow joint may be provided at the side wall 2011 or the cover, and the cleaning liquid in the tank cavity flows out of the tank cavity through the overflow joint), so that the tank body 201 is kept continuously filled with the cleaning liquid, and can be continuously renewed.

The ultraviolet generating mechanism 202 is held by the tank body 201 and is configured such that the ultraviolet rays emitted therefrom are directed into the tank cavity. The ultraviolet ray generating mechanism 202 may be an optical system for guiding ultraviolet rays into the tank 201. That is, the ultraviolet rays may be an optical path system for guiding the path of the light rays, which does not generate ultraviolet rays by itself.

Alternatively, in other examples, ultraviolet generating mechanism 202 may be a mechanism having a light source and an optical path directing system. For example, the ultraviolet generating mechanism 202 may include an ultraviolet lamp light source and a fiber optic structure. Alternatively, the ultraviolet generating mechanism 202 may be an ultraviolet lamp having a linear structure. It may be laid on the inner surface of the bottom wall 2012 of the tank 201 or on the inner surface of the side wall 2011. Alternatively, when the housing 201 is made of transparent material, the ultraviolet lamp may be fixed to the outer arm of the housing 201 or placed outside the housing 201. Or the ultraviolet lamp can be hung in the groove cavity of the groove body 201. Alternatively, the ultraviolet generating mechanism 202 may be fixed to the cover.

In addition, the washer may further include a switch electrically connected to the ultraviolet ray generation mechanism 202 based on the selection of the ultraviolet ray irradiation method. The switch-on light can be used to selectively switch on or off the connection of the uv generating mechanism 202 to the power source to activate uv irradiation or to deactivate when needed. In fig. 3, a row of ultraviolet lamps (6 groups, two in each group) are arranged at the bottom of the tank body, and when pure water enters the middle of the tank body from the bottom of the tank body, the pure water is irradiated by the ultraviolet lamps, so that organic matters in the pure water are effectively removed.

Alternatively, the washer may have a switch and a frequency generating mechanism as an alternative. The switch is electrically connected to the ultraviolet generating means 202 through the frequency generating means. In this manner, the frequency generating mechanism can be used to generate an on-off signal having a set fixed frequency, so that the switch and the ultraviolet generating mechanism 202 can be electrically connected on or off at the fixed frequency. In other words, the frequency generating means and the switch are engaged with each other, whereby the ultraviolet radiation can be intermittently irradiated at a predetermined constant frequency. For example, after 10 minutes of irradiation, the irradiation is suspended for 2 minutes, and the irradiation is continued for 10 minutes, which is repeated in this order. The frequency generating mechanism may be a timer, for example.

Based on this, the performance of the heterojunction solar cell can be optimized by implementing the organic matter removing operation through the device. In the scale production of the SHJ (silicon heterojunction), the conversion efficiency of the battery is improved, and the manufacturing cost of the battery can be reduced. For example, as measured by a conversion efficiency improvement of 0.03%: the conversion efficiency of the SHJ battery is measured according to 24% at 1.2 yuan per watt, and the yield per GW can be increased by 1.2 yuan per 1000000000 per 0.03%/24% per 300 ten thousand yuan per year.

Embodiments of the present application are described in detail above with reference to examples, but those skilled in the art will appreciate that the above-described exemplary examples are only illustrative of the present application and should not be construed as limiting the scope of the present application. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The present application is described in further detail with reference to examples below.

Example 1

The N-type monocrystalline silicon wafer is subjected to texturing by adopting a heterojunction conventional texturing process flow and proportion in the following manner. The process of making the wool comprises the following steps: precleaning, water tank, destroyer, water tank, SC1, water tank, texturing, water tank, SC1, water tank, CP, water tank, HF tank, water tank, and drying. Continuous 185nm ultraviolet irradiation was performed in all the steps of the water tank, CP, water tank, HF tank and water tank.

Then, the following operations are carried out on the silicon wafer after texturing: and sequentially manufacturing amorphous silicon, TCO and screen printing electrodes to obtain the heterojunction solar cell.

The cell performance was tested.

Comparative example 1

This example was carried out according to the procedure of example 1 and differs from example 1 in that: in this example, ultraviolet irradiation was not performed.

The test performance of the batteries in example 1 and comparative example 1 is shown in table 1.

As can be seen from Table 1, the conversion efficiency of the cell was also effectively increased by 0.03% by the UV lamp process, and the efficiency increase was mainly due to the increase of Voc (Voc increased by 0.8 mV).

Example 2

Texturing was performed according to the procedure using an N-type single crystal silicon wafer in the manner of example 1.

The silicon wafer is sequentially subjected to precleaning, water tank, damage removal, water tank, SC1, water tank, texturing, water tank, SC1, water tank, CP, water tank, HF tank, water tank and drying. In the final process water tank, HF tank and water tank, continuous 185nm ultraviolet irradiation was performed.

Then, the following operations are carried out on the silicon wafer after texturing: and sequentially manufacturing amorphous silicon, TCO and screen printing electrodes to obtain the heterojunction solar cell.

The cell performance was tested.

Comparative example 2

This example was carried out according to the procedure of example 2 and differs from example 2 in that: in this example, ultraviolet irradiation was not performed.

The test performance of the batteries in example 2 and comparative example 2 is shown in table 2.

As can be seen from the above Table 2, the conversion efficiency of the cell is also effectively increased by 0.02% by using the UV lamp process, and the efficiency increase is mainly derived from the increase of Voc (Voc is increased by 0.5 mV).

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.