CN103547654B - For texture etching solution composition and the texture etching method of crystal silicon chip - Google Patents

Abstract

The present invention relates to the texture etching solution composition for crystal silicon chip and texture etching method.The described texture etching solution composition for crystal silicon chip comprises basic cpd; Polysaccharide; The lipid acid of the optimum content together with polysaccharide, the metal-salt of lipid acid or their mixture, to be formed uniformly the texture with micro-cone structure on the surface of crystal silicon chip, to maximize the absorption of sun power while reducing luminous reflectance, thus improve luminous efficiency.

Description

Texture etching solution compositions and texture etching methods for crystalline silicon wafers

technical field

The invention relates to a texture etching composition and a texture etching method for a crystalline silicon wafer, which can uniformly form the surface of the crystalline silicon wafer to have a micro-cone structure, thereby improving luminous efficiency.

Background technique

In recent years, solar cells have grown rapidly and are called next-generation energy sources and electronic devices that directly convert clean energy (ie, solar energy) into electrical energy. This solar cell mainly has a P-type silicon semiconductor including silicon and boron added to silicon and includes a PN junction semiconductor substrate, wherein the P-type silicon semiconductor mainly has silicon and boron added to silicon, and the N-type silicon The semiconductor layer is formed by diffusing phosphorus (P) to the surface of a P-type silicon semiconductor.

When light (such as sunlight) irradiates a substrate with an electric field generated through a PN junction, electrons (-) and holes (+) in the semiconductor are excited, and these excited electrons (-) and holes (+ ) can move freely and randomly within the semiconductor. In this case, electrons (-) within the electric field formed by the PN junction can migrate to the N-type semiconductor, while holes (+) migrate to the P-type semiconductor. If electrons are provided both on the surface of the P-type semiconductor and on the surface of the N-type semiconductor so that the electrons flow to an external circuit, a current is generated. Based on this principle, solar energy is converted into electrical energy. Therefore, in order to improve the solar light conversion efficiency, the electrical output per unit area of the PN junction semiconductor substrate should be increased as much as possible, and for this purpose, the reflectance must be reduced while maximizing light absorption. Considering the situation described above, the solar cell silicon wafer for constructing the PN junction semiconductor substrate should have a micro-pyramid structure formed on its surface and can be provided with an anti-reflection film. Texturing the surface of a silicon wafer with micropyramidal structures reduces the reflectivity of incident light of various wavelengths, thereby increasing the amount of light absorbed. As a result, the performance of the solar cell (ie, the efficiency of the solar cell) can be improved.

A method for making the surface of a silicon wafer with a micropyramid structure has been disclosed, for example, U.S. Patent No. 4,137,123 describes a silicon texture etching solution, wherein, 0.5wt.% (weight percent) to 10wt.% The silicon is dissolved in an anisotropic etching (often referred to as 'dry etching') solution consisting of 0 to 75vol.% (volume percentage) of ethylene glycol, 0.05wt.% to 50wt. % of potassium hydroxide and the balance of water. However, such an etching solution cannot generate cones, thus increasing light reflectance and resulting in a decrease in light absorption efficiency.

Furthermore, European Patent No. 0477424 proposes a texture etching method in which oxygen is supplied to a texture etching solution comprising silicon dissolved in a mixture of ethylene glycol, potassium hydroxide, and the balance of water, Promptly carry out the inflation process of several minutes. However, the above-mentioned etching method cannot form a cone, which in turn increases light reflectance while deteriorating light absorption efficiency, and furthermore, has the disadvantage that an alternative gas filling device is also required.

In addition, Korean Patent Registration No. 0180621 discloses a texture etching solution comprising 0.5% to 5% potassium hydroxide solution, 3vol.% to 20vol.% isopropanol and 75vol.% to 96.5vol.% A mixture of deionized water; US Patent No. 6,451,218 discloses a texture etching solution comprising an alkaline compound, isopropanol, aqueous alkaline glycol, and water. However, since the above-mentioned etching solutions respectively include isopropyl alcohol having a relatively low boiling point and this substance must be additionally added during texturing, economical disadvantages are caused in terms of productivity and cost. In addition, the additionally added isopropanol produces temperature gradients in the etching solution, thereby increasing deviations in the texture quality over regions on the silicon wafer surface and ultimately degrading the homogeneity.

Contents of the invention

technical problem

Therefore, an object of the present invention is to provide a texture etching composition and a texture etching method for a crystalline silicon wafer, which can improve the uniformity of the texture in the region where the micropyramid structure is formed on the surface of the crystalline silicon wafer, thereby Improve luminous efficiency.

Another object of the present invention is to provide a texture etching solution composition for crystalline silicon wafers that does not require the application of an aeration process and the introduction of additional etching solution components during texturing.

In addition, another object of the present invention is to provide a texture etching method using the above texture etching solution for silicon wafers.

Technical solutions

(1) A texture etching composition for crystalline silicon wafers, comprising: 0.1wt.% to 20wt.% of basic compounds; 10 ^-9 wt.% to 10wt.% of polysaccharides; 10 ^-9 wt.% to 10wt% .% fatty acids, metal salts of fatty acids, or mixtures thereof; and, the balance water.

(2) The composition according to (1) above, wherein the basic compound is at least one selected from potassium hydroxide, sodium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide and tetraethylammonium hydroxide .

(3) The composition according to (1) above, wherein the polysaccharide is at least one selected from the group consisting of dextran compounds, fructan compounds, mannan compounds, galactan compounds, and metal salts thereof.

(4) The composition according to (3) above, wherein the polysaccharide is selected from the group consisting of cellulose, dimethylaminoethylcellulose, diethylaminoethylcellulose, ethylhydroxyethylcellulose, methylhydroxyethylcellulose Cellulose, 4-aminobenzyl cellulose, triethylaminoethyl cellulose, cyanoethyl cellulose, ethyl cellulose, methyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, hydroxyethyl cellulose Cellulose, hydroxypropyl cellulose, alginic acid, amylose, pullulan, pectin, starch, dextrin, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, hydroxypropyl- At least one of β-cyclodextrin, methyl-β-cyclodextrin, dextran, sodium dextran sulfate, saponin, glycogen, zymosan, lentinan, schizophyllan, and metal salts thereof A glucan compound.

(5) The composition according to (3) above, wherein the polysaccharide has an average molecular weight of 5,000 to 1,000,000.

(6) The composition according to (1) above, wherein the fatty acid is selected from the group consisting of acetic acid, propionic acid, butyric acid, valeric acid, heptanoic acid, caprylic acid, nonanoic acid, capric acid, lauric acid, myristic acid, palmitic acid, hard Fatty acid, arachidic acid, docosanoic acid, tetracosanoic acid, cerotic acid, eicosapentaenoic acid, docosahexaenoic acid, linoleic acid, α-linolenic acid, γ-linolenic acid, At least one of dihomo-γ-linolenic acid, arachidonic acid, oleic acid, elaidic acid, erucic acid, and nervonic acid.

(7) The composition according to (1) above, further comprising: At least one fluorine surface of amine salt, perfluoroalkyl quaternary ammonium salt, perfluoroalkyl carboxy betaine, perfluoroalkyl sultaine, fluoroalkyl polyoxyethylene and perfluoroalkyl polyoxyethylene As the active agent, each of the above-mentioned fluorosurfactants has 1 to 30 carbon atoms in each alkyl group thereof.

(8) The composition according to (1) above, further comprising: silica fine powder; Na ₂ O stabilized silica colloidal solution; K ₂ O stabilized silica colloidal solution; acid solution stabilized Silica colloidal solution _; NH Stabilized silica colloidal solution; Utilize at least one organic solvent stable silica colloidal solution selected from ethanol, propanol, ethylene glycol, methyl ethyl ketone and methyl isobutyl ketone; liquid sodium silicate; liquid potassium silicate; and at least one silicon compound of liquid lithium silicate.

(9) The texture etching method of a crystalline silicon wafer comprises: soaking a crystalline silicon wafer in the etching solution composition according to any one of (1) to (8) above, spraying the crystalline silicon wafer with the composition, or soak a silicon wafer in the composition and then spray the composition on the silicon wafer.

(10) The composition according to (9) above, wherein the soaking, spraying, or soaking and spraying is performed at a temperature of 50° C. to 100° C. for 30 seconds to 60 minutes.

Beneficial effect

According to the texture etching composition and texture etching method for crystalline silicon wafers of the present invention, microcone structures can be uniformly formed on the surface of crystalline silicon wafers to maximize solar energy absorption and improve luminous efficiency by reducing light reflection .

In addition, since the texture etching method according to the present invention does not need to apply an aeration process and introduce an additional etching solution during texturing, the method achieves an economical advantage in consideration of initial production and processing costs and can also form a uniform microstructure. cone structure.

Description of drawings

1 is a 3D optical microscopic image showing the surface of a single crystal silicon wafer subjected to texture etching by using a texture etching solution composition for a crystalline silicon wafer prepared in Example 10 of the present invention; and

2 is a scanning electron microscope (SEM) image showing the surface of a single crystal silicon wafer subjected to texture etching by using the texture etching solution composition for a crystalline silicon wafer prepared in Example 10 of the present invention.

Detailed ways

The invention discloses a texture etching composition for crystalline silicon wafers and a texture etching method using the texture etching composition.

Hereinafter, the present invention will be described in detail.

The texture etching composition for a crystalline silicon wafer of the present invention includes an alkaline compound; a polysaccharide; a fatty acid, a metal salt of a fatty acid, or a mixture thereof; and, a balance of water.

More specifically, the texture etching composition for crystalline silicon wafers of the present invention includes 0.1 wt.% to 20 wt.% of basic compounds; 10 ^-9 wt.% to 10 wt.% of polysaccharides; 10 ^-9 wt.% Up to 10 wt.% of fatty acids, metal salts of fatty acids, or mixtures thereof; and, the balance of water.

The basic compound is a component that etches the surface of the crystalline silicon wafer and the kind of the component is not particularly limited. For example, potassium hydroxide, sodium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide and the like are used. Among these basic compounds, potassium hydroxide and sodium hydroxide are preferably used. These compounds may be used alone or in combination of two or more of them.

The basic compound may be included in a content of 0.1 wt.% to 20 wt.%, preferably 1 wt.% to 5 wt.%, based on 100 wt.% of the total texture etching solution composition for crystalline silicon wafers. If the content of the basic compound is within the above range, the silicon wafer surface can be etched.

The texture etching solution composition for crystalline silicon wafers according to the present invention may further include polysaccharides in an optimum content.

Polysaccharides are polymer compounds formed by glycosidic bonding between two monosaccharides or more monosaccharides. Polysaccharides can prevent excessive etching and effectively control the acceleration of etching caused by the use of basic compounds, thereby preparing uniform Micro-cones and improved appearance, while quickly reducing hydrogen bubbles generated by etching away the surface of the silicon wafer, thereby preventing the occurrence of bubble cavities.

Examples of polysaccharides may include dextran compounds, fructan compounds, mannan compounds, galactan compounds, and metal salts thereof. Among these compounds, dextran compounds and metal salts thereof (such as alkali metal salts) are preferably used. The above-mentioned substances may be used alone or in combination of two or more of them.

For example, dextran compounds may include cellulose, dimethylaminoethylcellulose, diethylaminoethylcellulose, ethylhydroxyethylcellulose, methylhydroxyethylcellulose, 4-aminobenzylcellulose , triethylaminoethyl cellulose, cyanoethyl cellulose, ethyl cellulose, methyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, Alginic acid, amylose, pullulan, pectin, starch, dextrin, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, hydroxypropyl-β-cyclodextrin, methyl- β-cyclodextrin, dextran, sodium dextran sulfate, saponin, glycogen, zymosan, lentinan, schizophyllan, and metal salts thereof.

The polysaccharide may have a molecular weight of 5,000 to 1,000,000, preferably 50,000 to 200,000.

The polysaccharide may be included in a content of 10 ⁻⁹ wt.% to 10 wt.%, preferably 10 ⁻⁶ wt.% to 1 wt.%, based on 100 wt.% of the total texture etching solution composition for crystalline silicon wafers. If the content of the polysaccharide is within the above range, excessive etching can be prevented and etching acceleration can be effectively controlled. When the content of the polysaccharide exceeds 10 wt.%, the etching rate when using the basic compound may decrease sharply, which makes it difficult to form the desired microcones.

The texture etching solution composition for a crystalline silicon wafer according to the present invention may include an optimal content of fatty acid, metal salt of fatty acid, or a mixture thereof in addition to polysaccharide.

Fatty acids or their metal salts are components that are used together with polysaccharides to prevent over-etching caused by basic compounds to prepare uniform microcones while rapidly reducing hydrogen bubbles generated by etching away the surface of silicon wafers, This prevents the occurrence of air bubble cavities.

The fatty acid may be a hydrocarbon chain carboxylic acid having a carboxyl group, and may include, among others, acetic acid, propionic acid, butyric acid, valeric acid, heptanoic acid, caprylic acid, nonanoic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, peanut Acid, docosanoic acid, tetracosanoic acid, cerotic acid, eicosapentaenoic acid, docosahexaenoic acid, linoleic acid, alpha-linolenic acid, gamma-linolenic acid, dihomo-gamma -Linolenic acid, arachidonic acid, oleic acid, elaidic acid, erucic acid, nervonic acid, etc. In addition, metal salts of fatty acids may include ester reactants such as the aforementioned fatty acids with NaOH or KOH. The above-mentioned substances may be used alone or in combination of two or more of them.

Based on 100 wt.% of the total amount of the texture etching solution composition for crystalline silicon wafers, fatty acids, metal salts of fatty acids, or mixtures thereof may be included in an amount of 10 ^-9 wt.% to 10 wt.%, preferably 10 ^{- 6} wt.% to 1 wt.%. When the content of the fatty acid, the metal salt of the fatty acid, or the mixture thereof is within the above range, overetching can be effectively prevented.

The texture etching solution composition for crystalline silicon wafers of the present invention may further include a fluorine surfactant.

The fluorosurfactant lowers the surface tension of the etching solution to greatly promote improvement in wettability of the surface of the crystalline silicon wafer, thereby preventing over-etching caused by basic compounds.

For example, types of fluorosurfactants may include, but are not limited to: anionic surfactants such as perfluoroalkyl carboxylates, perfluoroalkyl sulfonates, perfluoroalkyl sulfates, fluoroalkyl phosphates etc.; cationic surfactants, such as perfluoroalkylamine salts, perfluoroalkyl quaternary ammonium salts, etc.; amphoteric surfactants, such as perfluoroalkylcarboxybetaines, perfluoroalkylsulfobetaines, etc.; and , Non-ionic surfactants, such as fluoroalkyl polyoxyethylene, perfluoroalcohol polyoxyethylene, etc. Each of these compounds may have 1 to 30 carbon atoms in its alkyl group. These substances may also be used alone or in combination of two or more of them.

Based on 100wt.% of the total amount of the texture etching solution composition for crystalline silicon wafers, the fluorosurfactant can be added in a content of ^10-9 wt.% to 10wt.%, preferably ^10-6 wt.% to 1wt.%. included. When the content of the fluorosurfactant is within the above range, the wettability of the surface of the silicon wafer can be effectively improved.

The texture etching solution composition for a crystalline silicon wafer of the present invention may further include a silicon compound.

The silicon compound is a component to be physically adsorbed to the surface of the crystalline silicon wafer and used as a kind of mask, thereby enabling the surface of the crystalline silicon wafer to have a micropyramidal shape.

The silicon compound may include a powdery silicate compound, a colloid solution type silicate compound, or a liquid phase silicate compound, or the like. More specifically, silica fine powder; Na ₂ O stabilized silica colloidal solution; K ₂ O stabilized silica colloidal solution; acid solution stabilized silica colloidal solution; NH ₃ stabilized silica colloidal solution ; a colloidal silica solution stabilized by at least one organic solvent selected from ethanol, propanol, ethylene glycol, methyl ethyl ketone, and methyl isobutyl ketone; liquid sodium silicate; liquid potassium silicate; and liquid lithium silicate etc. can be exemplified and these compounds can be used alone or in combination of two or more of them.

The silicon compound may be included in an amount of 10 ⁻⁹ wt.% to 10 wt.%, preferably 10 ⁻⁶ wt.% to 1 wt.%, based on 100 wt.% of the total amount of the texture etching solution composition for crystalline silicon wafers . If the content of the silicon compound is within the above range, microcones can be easily formed on the surface of the crystalline silicon wafer.

The texture etching solution composition for crystalline silicon wafers may further include water as the balance of the composition in a total amount of 100 wt.%.

The type of water is not particularly limited, however, deionized water is preferable, and deionized water for semiconductor processes having a specific resistance of 18 MΩ/cm or more is more preferable.

The texture etching composition for crystalline silicon wafers according to the present invention including the above-mentioned components may especially include fatty acids, metal salts of fatty acids, or mixtures thereof and polysaccharides in an optimal content so as to uniformly form on the surface of crystalline silicon wafers Micro-cone structure to maximize solar energy absorption while reducing light reflection, thereby improving luminous efficiency. Furthermore, since the texture etching method according to the present invention does not require a process of applying aeration during texturing and introducing additional etching solution components, the method achieves economical advantages in terms of productivity and processing cost.

The texture etching solution composition for crystalline silicon wafers according to the present invention can be suitably used in common etching processes such as dipping type etching, spraying type etching, embedding type etching and the like.

The present invention provides a texture etching method of a crystalline silicon wafer using the above-described texture etching solution composition for a crystalline silicon wafer.

The texture etching method of a crystalline silicon wafer may include soaking a crystalline silicon wafer in an etching solution composition for a crystalline silicon wafer, spraying the composition, or soaking the crystalline silicon wafer in the etching solution composition while spraying the composition. composition.

The number of soaking and/or spraying is not particularly limited, and in the case of simultaneous soaking and spraying, the order of their operations is also not limited.

Soaking, spraying, or soaking and spraying may be performed at a temperature of 50° C. to 100° C. for 30 seconds to 60 minutes.

As described above, the texture etching method of a crystalline silicon wafer according to the present invention does not need to apply an additional gas-filling device for supplying oxygen, and therefore, is economical in terms of initial production and processing costs and can form uniform microstructures even through a simple process. cone structure.

Hereinafter, preferred embodiments are described with reference to Examples and Comparative Examples in order to understand the present invention more specifically. However, it should be understood by those skilled in the art that these embodiments are provided for illustrative purposes, that various modifications and changes can be made without departing from the scope and spirit of the present invention, and that such modifications and changes are properly included in the present invention. within the scope of the invention as defined by the appended claims.

Example

Example 1

Prepared for Texture etching composition for crystalline silicon wafers.

Embodiment 2 to 17, comparative example 1 to comparative example 4

The same procedure as described in Example 1 was carried out except for using the components and their contents listed in Table 1 below. Here, the content refers to weight percentage (wt.%).

Table 1

Comparative Example 5

A texture etching composition for crystalline silicon wafers was prepared by mixing 1.5 wt.% potassium hydroxide (KOH), 5 wt.% isopropanol (IPA) and the balance deionized distilled water.

Comparative Example 6

The same procedure as described in Comparative Example 5 was followed except that ethylene glycol (EG) was used instead of isopropanol (IPA).

Comparative Example 7

The same procedure as described in Comparative Example 5 was followed except that methyldiethylene glycol (MDG) was used instead of isopropanol (IPA).

Comparative Example 8

The same procedure as described in Comparative Example 5 was followed except that monoethylamine (MEA) was used instead of isopropanol (IPA).

Experimental Example

For the various texture etching solution compositions for monocrystalline silicon wafers prepared in Examples 1-17 and Comparative Examples 1 to 8, evaluate the texture etching effect according to the following method, and the results of the evaluation are in the following table 2 shown in .

- Immersing the monocrystalline silicon wafer substrate with the prepared texture etching solution composition for monocrystalline silicon wafer at a temperature of 80° C. for 20 minutes.

(1) Uniformity of texture

The resulting deviation (i.e., uniformity) of the microstructure cones formed on the surface of the monocrystalline silicon wafer substrate after texture etching was visually observed using a digital camera, a 3D optical microscope, and a scanning electron microscope (SEM), according to the following evaluation criteria to evaluate the observed results.

<evaluation criteria>

◎: Cone is formed on the entire silicon wafer substrate

○: Cone does not appear on a part of the silicon substrate (the non-cone part is less than 5% of the silicon substrate)

△: No cones appear on a part of the silicon substrate (the non-cone portion accounts for 5% to 50% of the silicon substrate) ×: No cones are formed on most parts of the silicon substrate (non-cone The bulk part is equal to or greater than 90% of the silicon wafer substrate)

(2) Average size of the cone (μm)

Scanning electron microscopy (SEM) was used to measure the dimensions of the microcones formed on single crystal silicon wafers after texture etching. Here, after measuring the size of the microcones formed per unit area, the average value of the measured values was calculated and indicated.

(3) Average reflectance (%)

Using a UV spectrophotometer, the average reflectance was measured when light in the wavelength range of 400 nm to 800 nm was irradiated on the surface of the silicon single crystal wafer substrate obtained after texture etching.

Table 2

As shown in Table 2, when the substrate is used according to the texture etching solution composition in each of Examples 1 to 17 of the present invention (the composition includes an alkaline compound in an optimal content; polysaccharide; fatty acid, fatty acid Metal salt, or its mixture; And the water of balance) when carrying out texture etching, confirm that the microcone that forms on the surface of monocrystalline silicon wafer substrate has the mass deviation that reduces in the scope of microcone region to realize Good uniformity with low optical reflectance to increase luminous efficiency.

1 is a 3D optical microscopic image showing the surface of a crystalline silicon wafer texture-etched by using the texture etching solution composition prepared in Example 10; FIG. 2 is a photomicrograph showing the surface of a texture-etched crystalline silicon wafer. SEM images. As a result, it can be seen that microcones are formed on the entire surface of the silicon wafer, thereby reducing quality deviation and improving texture uniformity.

On the other hand, in the case of Comparative Example 1 not including the polysaccharide, etching proceeded rapidly to form cones having different sizes, and cones did not exist in most parts. Comparative Example 2, which did not include fatty acids or their metal salts, showed the absence of cones in some sections. Furthermore, for Comparative Example 3 having excess polysaccharide and Comparative Example 4 having excess fatty acid or metal salt thereof, the etching rate was greatly reduced to increase light reflectance. In addition, the texture etching composition in Comparative Example 5 had the problem that the temperature gradient generated when continuously introducing low-boiling isopropyl alcohol (IPA) resulted in failure to form texture and increased cost. In addition, the texture etching composition in Comparative Example 6 exhibited significantly worse performance in terms of texture uniformity and light reflection as compared with Examples of the present invention. In addition, the texture etching compositions in Comparative Example 7 and Comparative Example 8 respectively changed with time when the temperature was increased to the texturing temperature.

Claims (9)

1. A texture etchant for crystalline silicon wafers, by weight percentage, comprising: Basic compounds: 0.1% to 20%; Polysaccharides: ^10-9 % to 10%; Fatty acids, metal salts of fatty acids, or mixtures thereof: ^10-9 % to 10%; and Water: balance to 100%, Wherein, the fatty acid is selected from acetic acid, propionic acid, butyric acid, valeric acid, heptanoic acid, caprylic acid, nonanoic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid , Licosanoic Acid, Celic Acid, Eicosapentaenoic Acid, Docosahexaenoic Acid, Linoleic Acid, α-Linolenic Acid, γ-Linolenic Acid, Dihomo-γ-Linolenic Acid, Arachidonic Acid at least one of acid, oleic acid, elaidic acid, erucic acid, and nervonic acid. 2. The texture etchant according to claim 1, wherein the basic compound is selected from at least one of potassium hydroxide, sodium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide and tetraethylammonium hydroxide A sort of. 3. The texture etchant according to claim 1, wherein the polysaccharide is selected from at least one of glucan compounds, fructan compounds, mannan compounds, galactan compounds, and metal salts thereof . 4. The texture etchant according to claim 3, wherein the polysaccharide is selected from the group consisting of cellulose, dimethylaminoethyl cellulose, diethylaminoethyl cellulose, ethyl hydroxyethyl cellulose, methyl hydroxy Ethyl cellulose, 4-aminobenzyl cellulose, triethylaminoethyl cellulose, cyanoethyl cellulose, ethyl cellulose, methyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, hydroxy Ethyl cellulose, hydroxypropyl cellulose, alginic acid, pectin, starch, dextrin, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, hydroxypropyl-β-cyclodextrin, At least one dextran compound selected from methyl-β-cyclodextrin, dextran, sodium dextran sulfate, saponin, glycogen, zymosan, lentinan, schizophyllan, and metal salts thereof. 5. The texture etchant according to claim 3, wherein the polysaccharide has an average molecular weight of 5,000 to 1,000,000. 6. The texture etchant according to claim 1, wherein it also comprises a compound selected from perfluoroalkyl carboxylate, perfluoroalkyl sulfonate, perfluoroalkyl sulfate, perfluoroalkyl phosphate, perfluoroalkyl At least one fluorosurfactant of fluoroalkylamine salt, perfluoroalkyl quaternary ammonium salt, perfluoroalkyl carboxybetaine, perfluoroalkyl sulfobetaine and fluoroalkyl polyoxyethylene, all of the above Fluorosurfactants have 1 to 30 carbon atoms on each of their alkyl groups. 7. The texture etchant according to claim 1, wherein it also comprises fine powder selected from silicon dioxide; Na ₂ O stable silica colloidal solution; K ₂ O stable silica colloidal solution; acid solution stable Silica colloidal solution _; NH Stabilized silica colloidal solution; Utilize at least one organic solvent stable silica colloidal solution selected from ethanol, propanol, ethylene glycol, methyl ethyl ketone and methyl isobutyl ketone ; liquid sodium silicate; liquid potassium silicate; and at least one silicon compound in liquid lithium silicate. 8. A texture etching method for a crystalline silicon wafer, comprising: immersing the crystalline silicon wafer in the etching solution according to any one of claims 1 to 7, spraying the texture etchant on the crystalline silicon wafer , or soak the silicon wafer in the texture etchant and then spray the texture etchant on the silicon wafer. 9. The method of claim 8, wherein the soaking, spraying, or soaking and spraying are performed at a temperature of 50°C to 100°C for 30 seconds to 60 minutes.