Antireflection and light emission properties of silicon nanopyramids

Abstract

In this work, the antireflection and light emission properties of silicon nanopyramids (SiNPys) were studied via reflectivity and photoluminescence (PL) emission measurements. Arrays of disordered SiNPys were fabricated via anisotropic etching in an alkaline solution at room temperature. Enhancement of the orange-red light emission was observed from SiNPys etched for longer periods of time. The enhancement is ascribed to efficient light absorption induced by the nanopyramids and increased surface defects. This was supported from the decreased reflectivity from the pyramidal structures with further etching. The characteristic dimensions of the pyramidal structures were determined from the Scanning Electron Microscope (SEM) images. Results show the possibility of a relatively simple, low-cost, and robust route of integrating light-emitting and anti-reflecting nanostructures on silicon which is the platform of current electronic and optoelectronic devices.