Fabrication and Characterization of Free-Standing DBR Porous Silicon Film

Abstract

Distributed Bragg reflector porous silicon of different characteristics were formed to determine their optical constants in the visible wavelength range using a periodic square wave current between low and high current densities. The surface and cross-sectional SEM images of distributed Bragg reflector porous silicon were obtained using a cold field emission scanning electron microscope. The surface image of distributed Bragg reflector porous silicon indicates that the distributions of pores are even. The cross-sectional image illustrates that the multilayer of distributed Bragg reflector porous silicon exhibits a depth of few microns and applying of square current density during the etching process results two distinct refractive indices in the contrast. Distributed Bragg reflector porous silicon exhibited a porosity depth profile that related directly to the current-time profile used in etch. Its free-standing film was obtained by applying an electropolishing current.

Chemical Sensors Based on Distributed Bragg Reflector Porous Silicon Smart Particles

“…However, the further downsizing of sensor is required for the lower power consumption with improved reliability of sensor nets is driving the size of the motes down. Previously, we reported the fabrication of freestanding DBR PSi [27] and DBR smart particles. In the present work, we reported three different surface-mod-ified DBR smart particles and their use for sensing application to demonstrate specificity for the volatile organic vapors.…”

Fabrication and Characterization of Optically Encoded Porous Silicon Smart Particles

“…However, the further downsizing of sensor is required for the lower power consumption with improved reliability of sensor nets is driving the size of the motes down. Previously, we reported the fabrication of freestanding DBR PSi film [27] . In the present work, we reported a simple preparation of porous smart particle based on DBR PSi.…”