Antireflective microstructures for silicon photodetector surfaces

A photodetector efficiency is closely related to the light quantity trapped inside the structure. To reduce the reflectance, microstructures of different shapes can be carved by photolithographic and anisotropic etching procedures on silicon wafers meant to be used in photodetecting devices. Areas of inverted pyramids and deep vertical-wall grooves obtained in this way on (100) and [110]-oriented single-crystal silicon wafers were characterized by reflectance measurements.