Plasma etched c-Si wafer with proper pyramid-like nanostructures for photovoltaic applications

Abstract Dry and maskless texturing process of mono-crystalline silicon wafers using CF 4 /O 2 plasma in a reactive ion etching (RIE) system has been developed with the aim of obtaining optimized surface texture characterized by low optical reflection loss for photovoltaic applications. In this study c-Si has been successfully subjected to plasma etching at unusual process conditions, specifically high value of substrate temperature (15 °C) coupled with high value of process pressure (40 Pa). Different c-Si surface textures are produced at different etch durations. Specifically, pyramid-like morphology appears at very short etch time and crater-like nanostructures form at longer etch time, whereas the former gives the lowest average reflectance (