Influence of Temperature on Acid‐Based Wet Chemical Texturization for Ultralow Optical Reflectance (<2%) of mc‐Si Wafer for PV Applications

Abstract

AbstractThis study proposes a method to enhance the efficiency and optical properties of silicon solar cells made from as‐cut boron‐doped p‐type multicrystalline silicon (mi‐Si) wafers through acid‐based chemical texturization. Achieving lower reflectance is crucial for improving solar cell efficiency, and this can be attained through optimized chemical etching. The research demonstrates achieving a reflectance below 2% on the wafer surface after optimal chemical etching. Wet chemical etching is employed as the surface treatment method, using the same chemical etchant with varying conditions for the texturing process. The study compares temperature‐maintained chemical etching and without temperature maintenance. The chemicals used include HF + HNO3 + CH3COOH at temperatures of 50 °C and room temperature, with etching durations of 2, 5, 10, and 15 minutes, respectively. The as‐cut boron‐doped p‐type mc‐Si wafer grains are analyzed using UV‐vis spectroscopy, optical microscopy, Fourier transform infrared spectroscopy, thickness profilometry, scanning electron microscopy, and X‐ray diffraction spectroscopy, both before and after etching. Among the different conditions tested, the chemical etchant HF + HNO3 + CH3COOH at 50 °C for a 5‐minute etching duration yields favorable results, with reflectivity below 2%. The orientation of mc‐silicon wafer grains is determined using X‐ray diffraction spectroscopy.