CN114823943B - Suede structure, monocrystalline silicon wafer containing same, and texturing method and application - Google Patents

Suede structure, monocrystalline silicon wafer containing same, and texturing method and application Download PDF

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CN114823943B
CN114823943B CN202210281252.0A CN202210281252A CN114823943B CN 114823943 B CN114823943 B CN 114823943B CN 202210281252 A CN202210281252 A CN 202210281252A CN 114823943 B CN114823943 B CN 114823943B
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texturing
silicon wafer
additive
polyacrylamide
pyramid
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CN114823943A (en
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徐杨
姚伟明
张敏敏
强飞
虢小康
斯小阳
夏庆华
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Huzhou Flying Deer Amperex Technology Ltd
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    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02—Details
    • H01L31/0236—Special surface textures
    • H01L31/02363—Special surface textures of the semiconductor body itself, e.g. textured active layers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
    • H01L31/054—Optical elements directly associated or integrated with the PV cell, e.g. light-reflecting means or light-concentrating means
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
    • H01L31/1804—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof comprising only elements of Group IV of the Periodic Table
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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Abstract

The invention relates to the field of monocrystalline silicon battery manufacturing, in particular to a suede structure, which comprises single suede structures which are randomly distributed and are in an octagon pyramid structure, wherein the bottom surface of each single suede structure is in an octagon shape, and the part above the bottom surface is in an octagon shape. The invention overcomes the defects of short optical path, high reflectivity and poor light trapping effect caused by the smaller specific surface area of the pyramid structure of the common tetrahedron in the prior art. The suede structure comprises the single-body wool making structure with the eight-pyramid structure, so that the surface area of the eight-pyramid structure can be effectively improved on the premise of consistent bottom surface area, the optical path is increased, the reflectivity of light is reduced, and the suede structure has a better light trapping effect on the light.

Description

Suede structure, monocrystalline silicon wafer containing same, and texturing method and application
Technical Field
The invention relates to the field of monocrystalline silicon battery manufacturing, in particular to a textured structure, a monocrystalline silicon wafer containing the textured structure, a texturing method and application.
Background
The world economy is rapidly growing, the demand of human beings for energy is increasing, and the rapid shortage of non-renewable resources such as petroleum, natural gas, coal mine and the like is caused, and environmental pollution and energy shortage are factors which severely restrict the social development.
Solar energy resource is a real green environment-friendly energy source, and is an urgent need of human society due to inexhaustible use. An important way to apply solar energy to life is photovoltaic power generation, and silicon wafers are the most important raw materials in the photovoltaic power generation industry. By increasing the absorption of light on the surface of the silicon wafer, the efficiency of the crystalline silicon solar cell can be improved, and the production cost of the crystalline silicon solar cell can be reduced. The chemical texturing technology is adopted to corrode the surface of the silicon wafer, so that the textured surface which is uniform in size, good in roughness and proper in reflectivity is manufactured, and the photoelectric conversion efficiency of the solar cell can be effectively improved, wherein alkali texturing is a primary texturing means of single crystals at the present stage.
For the photovoltaic market in China, great changes occur in recent years, and part of enterprises already master advanced single crystal production processes and become the seeker of the global photovoltaic market. The wool making additive plays a very important role in monocrystalline wool making, on one hand, assists the wool making process, controls the reaction rate and adjusts the wool surface morphology, and on the other hand, solves the problems in the wool making process, such as non-uniform wool surface, raindrop printing, spots and the like.
The texture structures obtained by the traditional alkali texture additive are pyramid-shaped texture surfaces, and comprise forward pyramids and inverted pyramids, and the difference is only in the size and the height of the pyramids.
For example, the preparation method of the crystalline silicon surface inverted pyramid-like suede structure comprises the steps of firstly forming an alumina particle layer on the surface of a silicon wafer through pretreatment, and then performing alkali velvet making on the pretreated silicon wafer to obtain the inverted pyramid-like suede structure; the alumina particle layer is composed mainly of dispersed alumina particles. The preparation method of the inverted pyramid-like suede structure on the surface of the crystalline silicon is suitable for monocrystalline silicon wafers and polycrystalline silicon wafers, and can form uniform, fine and dense inverted pyramid-like suede structures on the surface of the silicon wafers.
The application number is CN202110953879.1, and the quick-speed texturing additive comprises the following components in percentage by mass: 0.5 to 10 percent of nucleating agent, 1 to 10 percent of suede catalyst, 0.01 to 0.05 percent of surfactant, 0.05 to 0.5 percent of defoaming agent and the balance of deionized water. The single-sided etching depth of the texturing additive reaches 1.5um, so that the complete growth of a positive pyramid can be realized, and the size of the texturing additive with 2um can be obtained.
The existing pyramid-shaped suede has the defects that the cell efficiency can still be kept at a higher level, but the specific surface area of the pyramid structure of a common tetrahedron is smaller, so that the optical path is shorter, the reflectivity is higher, and the light trapping effect is poorer.
Disclosure of Invention
The invention provides a suede structure, a monocrystalline silicon wafer containing the same, a wool making method and application thereof, and aims to overcome the defects that the common tetrahedron pyramid structure in the prior art is short in specific surface area, so that the optical path is short, the reflectivity is high, and the light trapping effect is poor.
In order to achieve the purpose of the invention, the invention is realized by the following technical scheme:
a first object of the invention is to provide a pile structure,
the suede structure comprises monomer suede structures which are randomly distributed and are in an eight-pyramid structure;
the bottom surface of the single-body texturing structure is octagonal, and the part above the bottom surface is in an octagon shape.
The suede structure comprises the single-body wool making structure with the eight-pyramid structure, so that the surface area of the eight-pyramid structure can be effectively improved on the premise of consistent bottom surface area, the optical path is increased, the reflectivity of light is reduced, and the suede structure has a better light trapping effect on the light.
Compared with the regular pyramid suede of the traditional rectangular pyramid structure, the suede structure is flatter, so that the silicon wafer is better contacted with the slurry in the subsequent passivation stage.
In addition, in the aspect of electrical performance, the single texturing structure of the octagon pyramid structure also increases short-circuit current and filling factor, so that the conversion efficiency of the solar cell is improved.
Preferably, the bottom side length of the single-body texturing structure is 0.3-1 mu m;
the height of the monomer texturing structure is 0.7-1.0 mu m;
the included angle of the top of each side edge of the single body texture surface making structure is 45-60 degrees.
Preferably, the specific surface area of the suede structure is more than or equal to 1.5.
A second object of the present invention is to provide a monocrystalline silicon wafer,
the surface of the monocrystalline silicon piece is distributed with the suede structure.
Preferably, the distribution density of the monomer texture structure in the texture structure on the surface of the monocrystalline silicon piece is 10 4 —10 6 And/mm.
The third object of the invention is to provide a monocrystalline silicon piece texturing method,
the method comprises the following steps:
(1) Preparing alkali liquor, adding a texturing additive into the alkali liquor, and uniformly stirring to obtain a texturing solution;
(2) Placing the silicon wafer into texturing solution for texturing to prepare a textured silicon wafer with the textured structure;
the texturing additive comprises the following components in percentage by weight: 1-5 wt% of alkyl sulfonate, 0.15-1 wt% of polyacrylamide, 0.5-5 wt% of alkylphenol ethoxylate and the balance of water.
The inventor of the present invention has found in daily experiments that, after the above-mentioned texturing additive is added into the texturing solution, it is possible to induce the surface of the silicon wafer to form a single texturing structure having an octagon pyramid structure during the texturing process.
The reason is presumed that the texturing additive of the invention contains a plurality of different surfactants at the same time, and the surfactants can induce different crystal faces of the silicon crystal, so that the corrosion effect of the silicon crystal can be anisotropic when the different crystal faces are corroded by sodium hydroxide in the texturing process, and thus, the octagon structure textured surface with uniform and stable structure is formed after the texturing is finished.
Compared with the traditional tetrahedron regular pyramid structure, the surface area of the eight-pyramid structure suede formed by the texturing additive is effectively increased, so that the optical path is increased, the reflectivity of light is reduced, and the suede structure has a better light trapping effect on the light. Compared with the traditional regular pyramid suede, the suede structure is flatter, so that the silicon wafer is better contacted with the slurry in the subsequent passivation stage. In addition, in the aspect of electrical performance, the eight-pyramid suede structure also increases short-circuit current and the filling factor, so that the conversion efficiency of the solar cell is improved.
In addition, in the prior art, metal ions are often needed to participate in the velvet making process, a part of metal ions remain in the inverted pyramid structure after the velvet making is finished, the inverted pyramid structure is difficult to clean, and the remaining metal ions form a composite center with crystalline silicon after entering the silicon crystal, so that the battery efficiency is affected. The invention can effectively avoid the defects because the participation of metal ions is not needed in the flocking process.
Furthermore, it was found through experiments by the inventors of the present invention that the content of each component in the above-mentioned texturing additive has a significant influence on the final texturing effect. When the content of the alkyl sulfonate is less than 1%, although the monomer texturing structure with an eight-pyramid structure can be formed, the monomer texturing structure can not be fully distributed on the surface of the whole silicon wafer, and more gaps still exist between the monomer texturing structures with the eight-pyramid structure, so that the performance of the monomer texturing structure can not meet the actual application requirements. When the content of the alkyl sulfonate is more than 5%, the eight pyramid suede structure disappears, and the eight pyramid suede structure becomes a common tetrahedron pyramid structure.
And after the content of the polyacrylamide is lower than 0.15%, the surface of the silicon wafer cannot be flocked, and when the content of the polyacrylamide is higher than 1%, the flock is too small, so that the light trapping effect of the silicon wafer is not improved.
And when the content of the alkylphenol ethoxylates is lower than 0.5%, the problem that the surface of the silicon wafer cannot be flocked is also caused, and when the content of the alkylphenol ethoxylates is higher than 0.5%, the flocked surface is dirty.
Preferably, the alkyl sulfonate has an alkyl carbon number of 12 or more.
The inventors of the present invention have found that the carbon chain length in the alkyl sulfonate has a significant impact on the overall texturing effect. The inventor tests that when the number of carbon atoms in the alkyl sulfonate is less than 12, the critical micelle concentration of the alkyl sulfonate is higher, and the detergency of the alkyl sulfonate is reduced, so that the product generated by corrosion in the flocking process cannot be removed rapidly, the reaction between alkali and a silicon wafer is delayed, the induction effect on the silicon wafer is poor, and a complete octagon pyramid flocked structure cannot be formed. The invention greatly improves the detergency after selecting the alkyl sulfonate with the alkyl carbon number of more than 12, so that byproducts generated in the texturing process can be rapidly wrapped by the alkyl sulfonate so as to be separated from the surface of the silicon wafer, the reaction between the silicon wafer and alkali can be more rapid, and the eight-pyramid textured structure is favorable for being induced on the surface of the silicon wafer.
Preferably, the alkyl sulfonate is one or a combination of more of sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate, sodium tridecyl sulfonate, sodium hexadecyl sulfonate and sodium n-octadecyl sulfonate.
Preferably, the polyacrylamide is nonionic polyacrylamide.
Preferably, the molecular weight of the polyacrylamide is 500-1000 ten thousand.
The inventor of the present invention found in experiments that the molecular weight of polyacrylamide has a large influence on the final formed suede, wherein when the molecular weight of polyacrylamide is less than 500 ten thousand, the adsorption and sedimentation effects of polyacrylamide on sodium silicate generated in the process of making the suede are poor, which is unfavorable for the reaction between the final alkali liquor and the silicon wafer. When the molecular weight of the polyacrylamide is more than 1000 ten thousand, the viscosity of the whole texturing liquid is larger, and hydrogen on the surface of the silicon wafer cannot be timely removed in the texturing process, so that the defects of the silicon wafer after the texturing is finished are more. Therefore, when the molecular weight of the polyacrylamide is selected to be 500-1000 ten thousand, alkali in the texturing liquid can quickly react with the silicon wafer, and meanwhile, hydrogen formed in the reaction process can be quickly discharged, so that defects such as raindrop marks, spots and the like are prevented from being formed on the surface of the silicon wafer.
Preferably, the addition mass of the texturing additive in the step (1) accounts for 0.2-0.5% of the whole texturing liquid.
Preferably, the texturing temperature in the step (2) is 70-90 ℃ and the texturing time is 5-10 min.
A fourth object of the invention is to provide the use of the textured structure or the monocrystalline silicon piece in a solar cell.
Therefore, the invention has the following beneficial effects:
(1) Compared with the traditional pyramid structure, the single texture structure of the eight-pyramid structure prepared by the invention has larger specific surface area, thereby increasing the optical path, reducing the reflectivity of light and ensuring that the texture structure has better light trapping effect on the light.
(2) Compared with the regular pyramid suede of the traditional rectangular pyramid structure, the suede structure is flatter, so that the silicon wafer is better contacted with the slurry in the subsequent passivation stage.
(3) In the aspect of electrical performance, the single texturing structure of the octagon pyramid structure also increases short-circuit current and filling factor, so that the conversion efficiency of the solar cell is improved.
Drawings
Fig. 1 is an electron micrograph of an octagon pyramid texture on the surface of a single crystal textured silicon wafer.
Fig. 2 is an enlarged view of a monomer texturing structure of an octagon pyramid structure.
Fig. 3 is a pile image formed after less than 1% alkyl sulfonate content.
Fig. 4 is a pile image formed after the alkyl sulfonate content is greater than 5%.
Fig. 5 is a photograph of a formed suede structure after the polyacrylamide content is less than 0.15%.
Fig. 6 is a picture of a pile structure formed after the content of polyacrylamide is higher than 1%.
Fig. 7 is a picture of a pile structure formed when the alkylphenol ethoxylate content is less than 0.5%.
Fig. 8 is a picture of a pile structure formed when the alkylphenol ethoxylate content is higher than 5%.
Detailed Description
The invention is further described below with reference to the drawings and specific examples. Those of ordinary skill in the art will be able to implement the invention based on these descriptions. In addition, the embodiments of the present invention referred to in the following description are typically only some, but not all, embodiments of the present invention. Therefore, all other embodiments, which can be made by one of ordinary skill in the art without undue burden, are intended to be within the scope of the present invention, based on the embodiments of the present invention.
Example 1
1. 1 wt% of sodium dodecyl sulfonate, 0.5-wt% of nonionic polyacrylamide with molecular weight of 500-1000 ten thousand, 1.5-wt% of alkylphenol ethoxylate and the balance of water.
Example 2
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.5wt%, alkylphenol ethoxylate 1.5 wt%, and the balance being water.
Example 3
3. 3 wt% of sodium dodecyl sulfonate, 0.5-wt% of nonionic polyacrylamide with molecular weight of 500-1000 ten thousand, 1.5-wt% of alkylphenol ethoxylate and the balance of water.
Example 4
5.5 wt% of sodium dodecyl sulfonate, 0.5-wt% of nonionic polyacrylamide with molecular weight of 500-1000 ten thousand, 1.5-wt% of alkylphenol ethoxylate and the balance of water.
Example 5
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.15 wt%, alkylphenol ethoxylate 1.5 wt%, and the balance being water.
Example 6
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.8 wt%, alkylphenol ethoxylate 1.5 wt%, and the balance water.
Example 7
2. 2 wt% of sodium dodecyl sulfonate, 1. 1 wt% of nonionic polyacrylamide with molecular weight of 500-1000 ten thousand, 1.5. 1.5 wt% of alkylphenol ethoxylate and the balance of water.
Example 8
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.5wt%, alkylphenol ethoxylate 0.5wt%, and the balance being water.
Example 9
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.5wt%, alkylphenol ethoxylate 2.5 wt% and the balance being water.
Example 10
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.5wt%, alkylphenol ethoxylate 4wt% and the balance of water.
Example 11
A wool making additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.5wt%, alkylphenol ethoxylate 5wt% and water for the rest.
Example 12
2. 2 wt% of sodium dodecyl benzene sulfonate, 0.5-wt% of nonionic polyacrylamide with molecular weight of 500-1000 ten thousand, 1.5-wt% of alkylphenol ethoxylate and the balance of water.
Example 13
A texturing additive, sodium cetyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.5wt%, alkylphenol ethoxylate 1.5 wt%, and the balance water.
Example 14
2. 2 wt% of sodium n-octadecylsulfonate, 0.5-wt% of nonionic polyacrylamide with molecular weight of 500-1000 ten thousand, 1.5-wt% of alkylphenol ethoxylate and the balance of water.
Comparative example 1
A wool making additive is prepared from sodium dodecyl sulfonate (0.5-wt%), non-ionic polyacrylamide (0.5-wt) with molecular weight of 500-1000 ten thousand, alkylphenol ethoxylate (1.5-wt%) and water (rest).
Comparative example 2
8. 8 wt% of sodium dodecyl sulfonate, 0.5-wt% of nonionic polyacrylamide with molecular weight of 500-1000 ten thousand, 1.5-wt% of alkylphenol ethoxylate and the balance of water.
Comparative example 3
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.1 wt%, alkylphenol ethoxylate 1.5 wt%, and the balance being water.
Comparative example 4
A wool making additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 1.5 wt%, alkylphenol ethoxylate 1.5 wt%, and water in balance.
Comparative example 5
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.5wt%, alkylphenol ethoxylate 0.3 wt% and the balance being water.
Comparative example 6
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.5wt%, alkylphenol ethoxylate 5.5 wt% and the balance being water.
Comparative example 7
A texturing additive, sodium n-octane sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 500-1000 ten thousand 0.5wt%, alkylphenol ethoxylate 1.5 wt% and the balance water.
Comparative example 8
2. 2 wt% of 1-decanesulfonate, 0.5-wt% of nonionic polyacrylamide with molecular weight of 500-1000 ten thousand, 1.5-wt% of alkylphenol ethoxylate and the balance of water.
Comparative example 9
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 200-400 ten thousand 0.5wt%, alkylphenol ethoxylate 1.5 wt%, and the balance being water.
Comparative example 10
A texturing additive, sodium dodecyl sulfonate 2 wt%, nonionic polyacrylamide with molecular weight of 1000-1500 ten thousand 0.5wt%, alkylphenol ethoxylate 1.5 wt%, and the balance being water.
The formulation of the texturing additives prepared in examples 1 to 14 and comparative examples 1 to 10 is summarized in the following table 1.
TABLE 1
Sequentially weighing the components according to the formulas in examples 1-14 and comparative examples 1-10, and stirring in a water bath at 60 ℃ for 3 hours; and then standing until the foam completely disappears, and finally filtering by a filter element with the pore diameter of 10 mu m to prepare the wool making additive.
The preparation of the wool making liquid and the wool making method are as follows:
adding 0.93-wt% NaOH and 0.4% wool making additive to form wool making liquid, stirring uniformly, and reacting at 80 ℃ for 7min to obtain the monocrystalline wool making silicon wafer.
(in the application, 0.4-wt% of the additive is selected as a reference additive, but through experiments of the inventor, the additive amount of the texturing additive is in the range of 0.2-0.5wt%, the texturing temperature is in the range of 70-90 ℃, and an octagon pyramid suede structure can be formed on the surface of the silicon wafer).
By adding the texturing additive in the embodiments 1-14, the surface of the monocrystalline textured silicon wafer can form an eight-pyramid textured structure, an electron micrograph of the surface of the monocrystalline textured silicon wafer prepared by the texturing additive in the embodiment 2 is shown in fig. 1, and fig. 2 is an enlarged view of the eight-pyramid textured structure.
As can be seen from figures 1-2, the eight-pyramid structure prepared by the invention has stable suede structure and can be closely and uniformly distributed on the surface of a silicon wafer, the side length of the bottom surface of the single-body suede structure is in the range of 0.3-1 mu m, the height of the single-body suede structure is in the range of 0.7-1.0 mu m, and the top included angle of each side edge of the single-body suede structure is 45-60 degrees.
Comparing examples 1-4 with comparative examples 1-2, we found that the amount of alkyl sulfonate added had a significant effect on the formation of the octagon suede structure. When the content of the alkyl sulfonate is less than 1%, although the texture of the octagon pyramid structure can be formed, the octagon pyramid texture cannot be fully distributed on the surface of the silicon wafer (as shown in fig. 3), and more gaps still exist between the octagon pyramid texture structures, so that the performance of the octagon pyramid texture cannot meet the actual application requirements. When the content of the alkyl sulfonate is more than 5%, the eight pyramid suede structure disappears, and the structure becomes a common tetrahedron pyramid structure (as shown in fig. 4).
Comparing examples 2, 5-7 with comparative examples 3-4, we found that the amount of polyacrylamide added also has an important effect on the formation of the octagon pyramid pile structure. After the content of the polyacrylamide is lower than 0.15%, the surface of the silicon wafer cannot be flocked (as shown in fig. 5), and when the content of the polyacrylamide is higher than 1%, the flock is too small (as shown in fig. 6), so that the light trapping effect of the surface of the silicon wafer is not improved.
Comparing examples 2, 8-11 with comparative examples 5-6, we found that the amount of alkylphenol ethoxylates added also has an important effect on the formation of octapyramid pile structures. When the content of alkylphenol ethoxylates is less than 0.5%, the problem that the surface of the silicon wafer cannot be flocked is also caused (as shown in fig. 7), and when the content of alkylphenol ethoxylates is more than 5%, the problem that the flocked surface is stained is also caused (as shown in fig. 8).
Comparing examples 2, 12-14 with comparative examples 7-8, we found that the length of the carbon chain in the alkyl sulfonate salt also has an important effect on the formation of the octapyramid pile structure. When the carbon amount is less than 12, the whole octagon pyramid structure cannot be formed, and only a common tetrahedron pyramid structure can be formed.
We have also found that the molecular weight of polyacrylamide also has an important effect on the formation of an octapyramid suede structure. When the molecular weight of the polyacrylamide is less than 500 ten thousand, the adsorption and sedimentation effects of the polyacrylamide on sodium silicate generated in the texturing process are poor, and the reaction between the final alkali liquor and the silicon wafer is not facilitated. When the molecular weight of the polyacrylamide is more than 1000 ten thousand, the viscosity of the whole texturing liquid is larger, and hydrogen on the surface of the silicon wafer cannot be timely removed in the texturing process, so that the defects of the silicon wafer after the texturing is finished are more. Therefore, when the molecular weight of the polyacrylamide is selected to be 500-1000 ten thousand, alkali in the texturing liquid can quickly react with the silicon wafer, and meanwhile, hydrogen formed in the reaction process can be quickly discharged, so that defects such as raindrop marks, spots and the like are prevented from being formed on the surface of the silicon wafer.
Finally, the velvet making additive in the embodiment 2 of the invention and a plurality of common pyramid velvet making additives which can be generated in the same size and height on the market are used for carrying out velvet making experiments at the same temperature, in water, with the use amount of NaOH, with the use amount of the additive and for the same reaction time, and then 5 points are randomly taken on a microscope to test the specific surface area, and the average value is obtained. And meanwhile, the reflectivity of the silicon wafer obtained after the texturing is finished is tested.
Wherein:
the formula of the additive (1) is as follows: 0.01% of cellulose sodium sulfonate, 0.1% of sodium carboxymethyl cellulose, 0.01% of tannic acid, 0.05% of hyperbranched polyacrylamide, 1% of potassium hydroxide and the balance of water.
The formula of the additive (2) is as follows: 0.1% sodium lignin sulfonate, 0.01% glycerol polyether, 0.3% hydroxyethyl-beta-cyclodextrin, 0.5% 1, 4-bis (2-hydroxyethyl) piperazine, and the balance water.
The formula of the additive (3) is as follows: 1% polyethylene glycol-600, 0.1% sodium benzoate, 1% citric acid, 1% hydrolyzed polymaleic anhydride, 0.1% g sodium acetate, the balance being water.
The formula of the additive (4) is as follows: 5% of hydrolyzed polyacrylonitrile sodium salt, 2% of choline, 0.02% of sodium dodecyl sulfate, 0.15% of toluenediamine polyether polyol with a viscosity of 12000mPa.s and the balance of water.
The formula of the additive (5) is as follows: sodium lignin sulfonate 0.05%, polynaphthalene formaldehyde sulfonate 0.0001%, polyethylene glycol 1.3%, diethylene glycol butyl ether 3.5%, potassium perfluorohexyl sulfonate 1.5%, and water in balance.
10L of water, 93g of NaOH and 40g of additive are added into a reaction tank, a monocrystalline silicon wafer is placed when the water temperature is raised to 80 ℃, the monocrystalline silicon wafer is reacted for 7 minutes, after the reaction, the silicon wafer is washed clean, the surface moisture is dried, and specific surface area test and reflectivity test are carried out, wherein the test results are shown in the following table 2.
TABLE 2
Product name Example 2 Additive (1) Additive (2) Additive (3) Additive (4) Additive (5)
Pyramid size/μm 1.64 1.6 1.59 1.68 1.7 1.65
Pyramid height/μm 0.89 0.86 0.85 0.9 0.92 0.88
Specific surface area 1.52 1.28 1.3 1.35 1.37 1.33
Reflectivity/% 9.56 9.73 9.85 9.97 9.65 10.12
Wherein: the specific surface area is defined as follows: surface area after texturing (μm) 2 ) Surface area before texturing (μm) 2 ）。
As can be seen from the data in the table, the texture structure of the eight-pyramid structure prepared by the invention has obviously increased specific surface area under the condition of close size, so that the optical path of light rays irradiated to the surface of the silicon wafer is obviously increased, the reflectivity of the light rays is reduced, and the light trapping effect of the texture structure on the light rays is better.

Claims (7)

1. A monocrystalline silicon slice texturing method is characterized in that,
the method comprises the following steps:
(1) Preparing alkali liquor, adding a texturing additive into the alkali liquor, and uniformly stirring to obtain a texturing solution;
(2) Placing the silicon wafer into texturing solution for texturing to prepare textured silicon wafer;
the texturing additive comprises the following components in percentage by weight: 1-5 wt% of alkyl sulfonate, 0.15-1 wt% of polyacrylamide, 0.5-5 wt% of alkylphenol ethoxylate and the balance of water;
the wool making additive comprises the following components: the alkyl carbon number of the alkyl sulfonate is more than or equal to 12; the polyacrylamide is nonionic polyacrylamide, and the molecular weight of the polyacrylamide is 500-1000 ten thousand;
the surface of the textured silicon wafer comprises a monomer textured structure which is randomly distributed and has an eight-pyramid structure;
the bottom surface of the single-body texturing structure is octagonal, and the part above the bottom surface is in an octagon shape.
2. The monocrystalline silicon piece texturing method according to claim 1, wherein,
the side length of the bottom surface of the monomer texturing structure is 0.3-1 mu m;
the height of the monomer texturing structure is 0.7-1.0 mu m;
the included angle of the top of each side edge of the single body texture surface making structure is 45-60 degrees.
3. A monocrystalline silicon piece texturing method according to claim 1 or 2, characterized in that,
the specific surface area of the monomer texturing structure is more than or equal to 1.5 mu m 2 。
4. The monocrystalline silicon piece texturing method according to claim 1, wherein,
monomer texturing structure in texturing structure on surface of silicon waferHas a distribution density of 10 4 —10 6 And/mm.
5. The monocrystalline silicon piece texturing method according to claim 1, wherein,
the addition mass of the texturing additive in the step (1) accounts for 0.2-0.5% of the whole texturing liquid.
6. The monocrystalline silicon piece texturing method according to claim 1, wherein,
and (3) the texturing temperature in the step (2) is 70-90 ℃ and the texturing time is 5-10 min.
7. Use of the method according to any one of claims 1 to 6 in a solar cell.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005072332A (en) * 2003-08-26 2005-03-17 Kyocera Corp Thin-film solar cell
JP2014192370A (en) * 2013-03-27 2014-10-06 Kaneka Corp Crystal silicon solar cell, process of manufacturing the same, and solar cell module
CN108666380A (en) * 2018-06-08 2018-10-16 南京纳鑫新材料有限公司 A kind of Buddha's warrior attendant wire cutting polysilicon chip and its etching method with class chamfered edge platform suede structure
CN111501105A (en) * 2020-05-25 2020-08-07 常州时创能源股份有限公司 Monocrystalline silicon piece texturing additive and application thereof
CN113683962A (en) * 2021-08-31 2021-11-23 马惠琪 Preparation method of silicon dioxide grinding and polishing agent

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005072332A (en) * 2003-08-26 2005-03-17 Kyocera Corp Thin-film solar cell
JP2014192370A (en) * 2013-03-27 2014-10-06 Kaneka Corp Crystal silicon solar cell, process of manufacturing the same, and solar cell module
CN108666380A (en) * 2018-06-08 2018-10-16 南京纳鑫新材料有限公司 A kind of Buddha's warrior attendant wire cutting polysilicon chip and its etching method with class chamfered edge platform suede structure
CN111501105A (en) * 2020-05-25 2020-08-07 常州时创能源股份有限公司 Monocrystalline silicon piece texturing additive and application thereof
WO2021238496A1 (en) * 2020-05-25 2021-12-02 常州时创能源股份有限公司 Monocrystalline silicon wafer texturing additive and use thereof
CN113683962A (en) * 2021-08-31 2021-11-23 马惠琪 Preparation method of silicon dioxide grinding and polishing agent

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