Optimization of a silicon wafer texturing process by modifying the texturing temperature for heterojunction solar cell applications

Abstract

In this work, a simple and effective method of two-step texturing temperature control is proposed to optimize the texturing process of commercial Cz-silicon wafers. The effective lifetime attained after passivation of the a-Si:H films is up to 1002.4 μs at a 10¹⁵ cm⁻³ injection level using this method, which is close to the bulk lifetime of the silicon wafers. This result shows over 50% enhancement compared with those achieved using constant texturing temperatures. Furthermore, a lower reflectivity after chemical polish treatment is achieved, and the scanning electron microscope (SEM) images demonstrate that pyramid nucleation is more homogeneous and compact. This method is found to remarkably improve the external quantum efficiency performance in the wave band of blue visible light and the fill factor of silicon heterojunction solar cells. This study provides a universal texturing process for heterojunction solar cell applications.