阅读说明：本技术 制备多层金字塔单晶硅绒面的两步制绒添加剂及其应用 (Two-step texturing additive for preparing multilayer pyramid monocrystalline silicon textured surface and application thereof ) 是由 李侠 张鹏伟 张新鹏 殷政 冯萍萍 于 2021-07-14 设计创作，主要内容包括：本发明属于太阳能电池单晶硅片表面处理技术领域。一种制备多层金字塔单晶硅绒面的两步制绒添加剂,包括添加剂A和添加剂B,所述添加剂A包括以下按质量百分比计算的组分：吐温0.02-5%、苯甲酸钠0.1-4.0%、硅酸钠0.12-8.0%以及余量的水；所述添加剂B包括以下按质量百分比计算的组分：为蛋白胨0.01-10%、葡萄糖0.01-10.0%、月桂醇聚氧乙烯醚0.01-10%、苯甲酸钠0.01-10%、吡啶0.01-10%以及余量的水。本发明两步制绒添加剂应用于单晶硅两步制绒工艺中,可形成更有利于吸收太阳光的多层金字塔结构单晶硅绒面,绒面具有更低的太阳光反射率值。(The invention belongs to the technical field of surface treatment of monocrystalline silicon wafers of solar cells. The two-step texturing additive for preparing the multilayer pyramid monocrystalline silicon textured surface comprises an additive A and an additive B, wherein the additive A comprises the following components in percentage by mass: tween 0.02-5%, sodium benzoate 0.1-4.0%, sodium silicate 0.12-8.0% and water in balance; the additive B comprises the following components in percentage by mass: is composed of peptone 0.01-10%, glucose 0.01-10.0%, polyoxyethylene lauryl ether 0.01-10%, sodium benzoate 0.01-10%, pyridine 0.01-10% and water in balance. The two-step texturing additive is applied to the two-step texturing process of the monocrystalline silicon, can form a multilayer pyramid-structure monocrystalline silicon textured surface which is more favorable for absorbing sunlight, and the textured surface has lower sunlight reflectivity.)

1. The two-step texturing additive for preparing the multilayer pyramid monocrystalline silicon textured surface is characterized by comprising an additive A and an additive B, wherein the additive A comprises the following components in percentage by mass: tween 0.02-5%, sodium benzoate 0.1-4.0%, sodium silicate 0.12-8.0% and water in balance; the additive B comprises the following components in percentage by mass: is composed of peptone 0.01-10%, glucose 0.01-10.0%, polyoxyethylene lauryl ether 0.01-10%, sodium benzoate 0.01-10%, pyridine 0.01-10% and water in balance.

2. The application of the two-step texturing additive according to claim 1, wherein the additive A is added in the first step texturing process and the additive B is added in the second step texturing process to prepare the monocrystalline silicon textured surface with the multilayer pyramid structure.

3. Use of the two-step texturing additive according to claim 2, wherein the single crystal silicon two-step texturing process comprises the steps of:

s1, mixing an alkaline solution with the concentration of 1-10wt% with an additive A to form a first reaction solution, and placing the cleaned monocrystalline silicon wafer into the first reaction solution for first-step texturing;

s2, placing the treated monocrystalline silicon wafer into water for cleaning;

s3, mixing the alkaline solution with the concentration of 1-10wt% with the additive B to form a second reaction solution, and placing the monocrystalline silicon piece obtained in the step S2 in the second reaction solution for second-step texturing to obtain the monocrystalline silicon textured surface with the multilayer pyramid structure.

4. The use of the two-step additive for texturing as claimed in claim 3, wherein the additive A is added in the first step texturing process in an amount of 0.1-10wt%, the reaction time is 100-600s, and the reaction temperature is 75-85 ℃.

5. Use of the two-step texturing additive according to claim 3, wherein the additive B is added in the second texturing process in an amount of 0.1 to 10 wt.%, the reaction time is 60 to 180s, and the reaction temperature is 75 to 85 ℃.

6. Use of a two-step texturing additive according to claim 3, wherein in step S2 the cleaning time is 60 to 180S and the cleaning temperature is 10 to 40 ℃.

7. Use of a two-step texturing additive according to claim 3, wherein the base in the alkaline solution comprises an organic base and an inorganic base.

8. Use of a two-step texturing additive according to claim 7, wherein the inorganic base is sodium hydroxide or potassium hydroxide.

9. Use of a two-step texturing additive according to claim 7, wherein the organic base is one of tetramethylammonium hydroxide, ethylenediamine, methanediamine, tetrabutylammonium hydroxide.

Technical Field

The invention belongs to the technical field of surface treatment of monocrystalline silicon wafers of solar cells, and particularly relates to a two-step texturing additive for preparing a multilayer pyramid monocrystalline silicon texture and application thereof.

Background

At present, photovoltaic power generation gradually becomes the key development direction of the power production industry in China, technical innovation of solar cells is promoted by flat-price networking, the primary key link in the production and manufacturing process of the monocrystalline silicon solar cells is to manufacture fluctuant and uneven suede on the surfaces of silicon wafers, namely monocrystalline silicon texturing, and the absorption of the silicon wafers to sunlight is increased by utilizing a light trapping principle, so that short-circuit current is increased, the specific surface area is increased, and finally the photoelectric conversion efficiency of the solar cells is improved. Most of the texture surfaces obtained by the existing monocrystalline silicon piece texture surface making process are pyramid structures, but the existing monocrystalline silicon texture surface making process has high sunlight reflectivity value and low photoelectric conversion efficiency of a solar cell. Therefore, further research on the texture of the texturing surface of the monocrystalline silicon is needed to obtain the texture more beneficial to absorbing sunlight, so as to obtain a lower sunlight reflectivity value.

Disclosure of Invention

The invention aims to solve the technical problem of providing a two-step texturing additive for preparing a multilayer pyramid monocrystalline silicon textured surface, wherein the two-step texturing additive is applied to a monocrystalline silicon two-step texturing process, so that the multilayer pyramid monocrystalline silicon textured surface which is more favorable for absorbing sunlight can be formed, and the textured surface has a lower sunlight reflectivity value.

The technical scheme of the invention is as follows:

the two-step texturing additive for preparing the multilayer pyramid monocrystalline silicon textured surface comprises an additive A and an additive B, wherein the additive A comprises the following components in percentage by mass: tween 0.02-5%, sodium benzoate 0.1-4.0%, sodium silicate 0.12-8.0% and water in balance; the additive B comprises the following components in percentage by mass: 0.01-10% of peptone, 0.01-10.0% of glucose, 0.01-10% of polyoxyethylene lauryl ether, 0.01-10% of sodium benzoate, 0.01-10% of pyridine and the balance of water.

The application of the two-step texturing additive disclosed by claim 1 in a monocrystalline silicon two-step texturing process, wherein the additive A is added in the first-step texturing process, and the additive B is added in the second-step texturing process to prepare a monocrystalline silicon textured surface with a multi-layer pyramid structure.

Further, the monocrystalline silicon two-step texturing process comprises the following steps:

s1, mixing an alkaline solution with the concentration of 1-10wt% with an additive A to form a first reaction solution, and placing the cleaned monocrystalline silicon wafer into the first reaction solution for first-step texturing;

s2, placing the treated monocrystalline silicon wafer into water for cleaning;

s3, mixing the alkaline solution with the concentration of 1-10wt% with the additive B to form a second reaction solution, and placing the monocrystalline silicon piece obtained in the step S2 in the second reaction solution for second-step texturing to obtain the monocrystalline silicon textured surface with the multilayer pyramid structure.

Furthermore, the addition amount of the additive A in the first step of the wool making process is 0.1-10wt%, the reaction time is 100-600s, and the reaction temperature is 75-85 ℃.

Furthermore, the additive B is added in the second step of texturing process at the weight percentage of 0.1-10, the reaction time is 60-180s, the reaction temperature is 75-85 DEG C

Further, in step S2, the cleaning time is 60-180S, and the cleaning temperature is 10-40 ℃.

Further, the alkali in the alkaline solution includes organic alkali and inorganic alkali.

Further, the inorganic base is sodium hydroxide or potassium hydroxide.

Further, the organic base is one of tetramethylammonium hydroxide, ethylenediamine and tetrabutylammonium hydroxide.

The invention has the following beneficial effects:

the two-step texturing additive is applied to a monocrystalline silicon two-step texturing process, and can form a multilayer pyramid structure monocrystalline silicon textured surface; the additive A is added in the first step of texturing process, so that a uniform pyramid structure can be grown on the surface of the monocrystalline silicon, and the absorption of the silicon wafer to sunlight is increased; the additive B is added in the second step of texturing process, which is beneficial to growing a multilayer pyramid structure on the surface of the monocrystalline silicon.

By adopting the two-step texturing additive, the multilayer pyramid-structure monocrystalline silicon textured surface prepared by the monocrystalline silicon two-step texturing process can greatly improve the light trapping property of the silicon wafer, so that the silicon wafer is more favorable for sunlight absorption, the reflectivity of the silicon wafer after texturing reaches 8.50% (tested by a D8 reflectivity tester, the selected wave band is 350-1050 nanometers), and the textured surface has a lower sunlight reflectivity value, thereby greatly improving the photoelectric conversion efficiency of the solar cell.

Drawings

FIG. 1 is a plan view of a scanning electron microscope of a multilayer pyramid structure obtained by two-step texturing of single crystal silicon in an embodiment of the present invention;

FIG. 2 is a plan view of a scanning electron microscope showing a pyramidal structure formed by texturing with single crystal silicon in a comparative example of the present invention.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and examples, which are only preferred embodiments of the present invention and are not intended to limit the present invention.

Example 1

The two-step texturing additive for preparing the multilayer pyramid monocrystalline silicon textured surface comprises an additive A and an additive B, wherein the additive A comprises the following components in percentage by mass: tween 2%, sodium benzoate 1%, sodium silicate 2.3% and the balance water; the additive B comprises the following components in percentage by mass: 5 percent of peptone, 3.6 percent of glucose, 4.5 percent of polyoxyethylene lauryl ether, 2.1 percent of sodium benzoate, 3 percent of pyridine and the balance of water.

A two-step texturing process of monocrystalline silicon comprises the following steps:

s1, mixing a sodium hydroxide solution with the concentration of 10wt% with an additive A to form a first reaction solution, placing the cleaned monocrystalline silicon piece into the first reaction solution to perform first-step texturing, wherein the additive A is added in the first-step texturing process in an amount of 2wt%, the reaction time is 480s, and the reaction temperature is 80 ℃.

S2, placing the processed monocrystalline silicon wafer into water for cleaning for 120s at the cleaning temperature of 30 ℃;

s3, mixing a 10wt% sodium hydroxide solution with an additive B to form a second reaction solution, placing the monocrystalline silicon wafer obtained in the step S2 in the second reaction solution for second-step texturing, wherein the additive B is added in an amount of 5wt% in the second-step texturing process, the reaction time is 120S, the reaction temperature is 80 ℃, the obtained monocrystalline silicon textured surface with the multilayer pyramid structure is shown in figure 1, and the lowest reflectivity is 8.50% (tested by a D8 reflectivity tester, the wave band is 350-plus 1050 nm).

Example 2

The two-step texturing additive for preparing the multilayer pyramid monocrystalline silicon textured surface comprises an additive A and an additive B, wherein the additive A comprises the following components in percentage by mass: tween 0.025%, sodium benzoate 0.1%, sodium silicate 8.0% and the balance water; the additive B comprises the following components in percentage by mass: is composed of peptone 0.01%, glucose 10.0%, polyoxyethylene lauryl ether 0.01%, sodium benzoate 10%, pyridine 0.01% and water in balance.

A two-step texturing process of monocrystalline silicon comprises the following steps:

s1, mixing a potassium hydroxide solution with the concentration of 10wt% with an additive A to form a first reaction solution, placing the cleaned monocrystalline silicon piece into the first reaction solution to perform first-step texturing, wherein the additive A is added in the first-step texturing process in an amount of 10wt%, the reaction time is 100s, and the reaction temperature is 75 ℃.

S2, placing the processed monocrystalline silicon wafer into water for cleaning for 60s at the cleaning temperature of 10 ℃;

s3, mixing a potassium hydroxide solution with the concentration of 10wt% with an additive B to form a second reaction solution, placing the monocrystalline silicon piece obtained in the step S2 in the second reaction solution for second-step texturing, wherein the additive B is added in the second-step texturing process in an amount of 10wt%, the reaction time is 60S, and the reaction temperature is 755 ℃, so that the monocrystalline silicon textured surface with the multilayer pyramid structure is obtained.

Example 3

The two-step texturing additive for preparing the multilayer pyramid monocrystalline silicon textured surface comprises an additive A and an additive B, wherein the additive A comprises the following components in percentage by mass: tween 5%, sodium benzoate 4.0%, sodium silicate 0.12% and the balance water; the additive B comprises the following components in percentage by mass: is composed of peptone 0.01%, glucose 10.0%, polyoxyethylene lauryl ether 0.01%, sodium benzoate 0.01%, pyridine 10% and water in balance.

A two-step texturing process of monocrystalline silicon comprises the following steps:

s1, mixing a tetramethylammonium hydroxide solution with the concentration of 10wt% with an additive A to form a first reaction solution, placing the cleaned monocrystalline silicon piece into the first reaction solution for first-step texturing, wherein the additive A is added in the first-step texturing process for 0.1t%, the reaction time is 600s, and the reaction temperature is 85 ℃.

S2, placing the processed monocrystalline silicon wafer into water for cleaning for 180s at the cleaning temperature of 40 ℃;

s3, mixing a tetramethylammonium hydroxide solution with the concentration of 10wt% with an additive B to form a second reaction solution, placing the monocrystalline silicon piece obtained in the step S2 in the second reaction solution for second-step texturing, wherein the additive B is added in the second-step texturing process in an amount of 10wt%, the reaction time is 180S, and the reaction temperature is 85 ℃, so that the monocrystalline silicon textured surface with the multilayer pyramid structure is obtained.

Comparative example

A monocrystalline silicon texturing process comprises the following steps:

s1, mixing a NaOH solution with the mass percentage of 1-10% with a monocrystalline silicon texturing additive to form a reaction solution, and placing a cleaned monocrystalline silicon piece into the reaction solution for texturing, wherein the reaction time is 100-600 seconds, and the cleaning temperature is 75-85 ℃;

s2, adding a monocrystalline silicon texturing additive which is 0.1-1.0% of a Mono RW 606 rapid texturing additive produced by New energy science and technology Limited company of Xian blue bridge into the reaction liquid obtained in the step S1;

s3, the monocrystalline silicon piece after the treatment is placed into deionized water to be cleaned, the cleaning time is 60-180 seconds, the cleaning temperature is 10-40 ℃, the reflectivity of the monocrystalline silicon texture surface with the pyramid structure is 9.5% as shown in figure 2 (tested by a D8 reflectivity tester, the selected wave band is 350-1050 nanometers).