Micro texturing of silicon using pulsed N_(2)-laser and formation mechanism

摘要

A low-cost pulsed N_(2)-laser has been used to successfully demonstrate the formation of self-organized conical microtexture in Si. The process is demonstrated in vacuum environment to avoid the use of SF_(6) gas and sulfur incorporation. The microtexture is formed with an average structure height of approx15 (mu)m, base diameter approx10 (mu)m, and tip-to-tip separation approx8 (mu)m. Energy dispersive x-ray spectroscopy of individual conelike structure shows that the material remains free from impurity incorporation. We have shown that the laser-induced-damage-related absorption can be successfully restored after an hour annealing at 1000 deg C, making the material an ideal candidate for photovoltaic and other photonic applications.