Monocrystalline silicon wafer texturing additive, texturing solution and corresponding texturing method

Abstract

The invention provides a monocrystalline silicon wafer texturing additive, a texturing solution and a corresponding texturing method. In the prior art, sodium silicate and the like are taken as monocrystalline silicon wafer texturing additives, a silicon wafer is bad in defoaming performance, and the defoaming effect can be guaranteed only by increasing the amount of a defoaming organic solvent, and thus the manufacturing cost is high and a pyramid texture surface is relatively large and not uniform in density at texturing later period. The monocrystalline silicon wafer texturing additive comprises terpilenol, polyglycol ether, lactic acid, sodium acetate and an alkali. The monocrystalline silicon wafer texturing solution comprises the above monocrystalline silicon wafer texturing additive and a texturing primary liquid, and the texturing primary liquid comprises an alkali, a defoaming organic solvent and deionized water. The monocrystalline silicon wafer texturing method comprises firstly providing the above monocrystalline silicon wafer texturing solution, controlling the texturing solution to have a constant temperature of 75-85 DEG C, placing a monocrystalline silicon wafer into the solution to make texture for 10-20 min, and finally using deionized water to clean the monocrystalline silicon wafer subjected to texturing. According to the technical scheme, the size of the pyramid texture surface can be effectively reduced, the technology stability and consistency are improved, the texture surface density is improved, and the production cost is reduced.

Description

technical field [0001] The invention relates to the field of solar cell manufacturing, in particular to a monocrystalline silicon wafer texturing additive, a texturing liquid and a corresponding texturing method. Background technique [0002] Crystalline silicon solar cells are still the mainstream in the photovoltaic industry. The preparation process of crystalline silicon solar cells includes the following steps: (1) chemical texturing and cleaning; (2) diffusion to prepare PN junctions; (3) etching to remove edges and cleaning ; (4) Preparation of anti-reflection film; (5) Screen printing electrodes and sintering; (6) Battery test sorting. The chemical texturing in the first step above is to form a textured surface on the surface of the silicon wafer and remove the damaged layer formed when the silicon wafer is cut. The monocrystalline silicon wafer usually uses an alkaline etching solution to form a pyramid with a good anti-reflection effect on the surface. Suede, the a...

AI Technical Summary

Problems solved by technology

Additives such as sodium silicate are currently used in the texturing process, and their ability to improve the interfacial tension between the silicon wafer and the solution is relatively poor. It is necessary to add a large amount of isopropanol to improve the bubble detachment ability, and as the reaction progresses, the silicon generated in the solution The concentration of sodium acid gradually increases, which weakens the control of the corrosion rate of the additives on the (100) / (111) crystal direction, so that the pyramid size becomes larger in the later use of the texturing liquid, such as figure 1 As shown, the size of the pyramid in the late use of the texturing solution exceeds 5um

Pyramid suede with such large particles is easy to cause damage to the suede in subsequent processes, resulting in low efficiency of solar cells

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