High-density hollow cathode plasma etching for large area multicrystalline silicon solar cells

Muleicrysalline silicon (mc-Si) materials are commercially important photovoltaic material. This material consists of number, of grains and grain boundaries. The orientation is generally random and the size of the grain varies between a few millimeters to several centimeters. So for multicrysalline silicon, surface texturization is not possible with help of standard NaOH /KOH or other anisotropic chemical enchant. Actually texturing for enhanced absorption in Silicon has been obtained by creating randomly distributed pyramids using anisotropic wet enchants, but this works well only on Single crystalline Silicon because of its <100> crystallographic orientation. Various surface texturization method has been used during surface preparation of mc-Si solar cell:research, including mechanical grinding, laserstructuring porous silicon etching, photolithographically defined etching etc. developed a mask less plasma texturing technique for mo-Si solar cells using high-density hollow cathode plasma etching technique. We used SF6 and O-2 gases in hollow cathode plasma (HCP) dry etching process. This-paper demonstrates very high plasma density of 2 x 10(12) cm(-3) at a discharge current of 20mA. Silicon etch rate of 1.3mum/min. was achieved with SF6/O-2 plasma conditions of total gas pressure =50 mTorr, gas flow rate=40 sccm, and RF power =100W. In this paper, we also reported the surface etching characteristics of monocrystalline silicon and large area multicrystalline silicon (mc-. Si) wafer.