Enhancing surface properties of monocrystalline silicon wafers via thermal annealing for solar cell texturing

Abstract

Monocrystalline silicon (mono-Si) solar cells are widely recognized for their high conversion efficiency and reliability, making them the dominant technology in the photovoltaic industry. However, these cells face performance challenges due to surface saw marks introduced by diamond wire saw (DWS) technology during the wafer slicing process. These defects disrupt the uniform formation of surface textures during subsequent alkaline etching, negatively affecting light absorption and overall solar cell efficiency. To address this issue, thermal annealing was explored as a pre-treatment method aimed at improving the surface properties of DWS mono-Si wafers. The study demonstrated that thermal treatment at 550 °C for 60 min significantly enhanced the surface reactivity and promoted more uniform texturing, which in turn improved light trapping and reduced reflectance. As a result, the optimized surface texturing led to a notable increase in solar cell performance, including a 0.22 % improvement in conversion efficiency. This approach presents an effective solution for enhancing the quality and efficiency of DWS mono-Si solar cells, offering a promising pathway to further advancements in photovoltaic technology and contributing to the development of more cost-effective and high-performance solar energy solutions.