Porous silicon-based quantum dot broad spectrum radiation detector

Abstract

Silicon is a convenient and inexpensive platform for radiation detection, but has low stopping power for x-rays and gamma-rays with high energy (e.g., 100 keV, as used in computed tomography and digital radiography, or 1 MeV as desired for detection of nuclear materials). We have effectively increased the stopping power of silicon detectors, by producing layers of porous or micro-machined silicon, and infusing this layer with semiconductor quantum dots made of electron-dense materials. Results of prototype detectors show sensitivity to infrared, visible light, and x-rays, with dark current of less than 1 nA/mm2. © 2011 IOP Publishing Ltd and SISSA.