Wideband ‘black silicon’ for mid-infrared applications

Abstract

In this paper, we investigate the absorption of mid-infrared light by low resistivity silicon textured via deep reactive ion etching. An analytical description of the wave propagation in black silicon texture is presented, showing agreement with the experiment and the computational analysis. We also study the dependence of absorption spectrum of black silicon structure on the electrical conductivity of silicon substrate. The structures investigated unveil wideband, allsilicon infrared absorbers applicable for infrared imaging and spectroscopy with simple CMOS compatible fabrication suitable for optoelectronic integration.

Optically Modulated Ultra-Broadband All-Silicon Metamaterial Terahertz Absorbers

“…All-dielectric broadband absorbers provide another approach. Notably, at infrared frequencies, all-silicon structures have been employed as broadband perfect absorbers. − Similar broadband perfect absorbers can be employed for THz applications. For example, disordered silicon metamaterials and double layered gratings have been employed to construct broadband perfect absorbers, but these structures require sophisticated design and fabrication of the silicon structures.…”