A preparation method of proximity soft film exposure micro-nano light-trapping structure

Abstract

The invention discloses a preparation method of a proximity soft membrane exposure micro-nano light trapping structure, and belongs to the technical field of solar cells. The method comprises the following steps of (1) preparing a hard template; (2) transferring a pattern of the hard template to a soft template; (3) pre-cleaning a solar cell silicon wafer and removing a surface damage layer; (4) coating the surface of the cleaned silicon wafer with a photoresist; (5) vertically adsorbing the soft template on the upper surface of the photoresist through vacuum pressure and carrying out exposure in parallel light; (6) pre-drying the exposed silicon wafer, developing the silicon wafer through a developing solution and finally drying the silicon wafer; and (7) obtaining a silicon substrate micro-nano light trapping structure through plasma etching or wet etching. By the micro-nano texture structure prepared by the method, reflection of the silicon substrate surface can be reduced; the texture structure is in a sub-micron scale or a nanoscale, uniform in size and controllable in shape, and is arranged according to a certain mode; and absorption and utilization of sunlight through the solar cell can be improved through the solar cell employing crystal silicon as the substrate.

Description

technical field [0001] The invention relates to a preparation method of a micro-nano texture, in particular to a preparation method of using a proximity soft film to expose a micro-nano light trapping structure on a silicon substrate of a solar cell, and belongs to the technical field of solar cells. Background technique [0002] Conventional fossil fuels are being used up day by day. As a clean energy, solar energy is the most potential energy source to replace fossil fuels. Crystalline silicon solar cell is a semiconductor electronic device that can effectively absorb solar radiation and convert it into electricity. It is currently the mainstream of solar cell development and occupies most of the market share. [0003] In order to reduce the reflectivity of the crystalline silicon surface, in the process of the solar cell, the crystalline silicon surface is textured to increase the absorption of light. Generally, single crystal silicon is etched by alkaline solution, and ...

AI Technical Summary

Problems solved by technology

However, in the nanoimprinting disclosed in CN 102148292 B, the pattern template is imprinted into the inside of the mask. After the imprint is exposed, a demoulding process is required. During the demolding process, due to the adhesion between the mask and the pattern template, a part of the mask Adhering to the pattern template, resulting in pattern loss and contamination of the pattern template, which affects the accuracy of the subsequent imprinting process; and the pattern template needs a certain pressure to be imprinted into the mask, which will cause pressure damage to the silicon wafer, resulting in The proportion of cracks in silicon wafers increases, which is not suitable for low-priced thin silicon wafers

Images