CdTe microwire-based ultraviolet photodetectors aligned by a non-uniform electric field

Abstract

We report on ultraviolet (UV) photodetectors fabricated by positioning Cadmium Telluride (CdTe) microwires (mu Ws) precisely by dielectrophoretic (DEP) force, where CdTe mu Ws were grown using an Au-catalyst-assisted closed-space-sublimation (CSS) method. The optical properties of CSS-grown CdTe mu Ws were characterized by micro-photoluminescence and micro-Raman spectroscopies. Optoelectronic characteristics were obtained after CdTe mu Ws were aligned on a pre-patterned SiO2/Si substrate by a non-uniform electric field. Photocurrents were increased with increasing the light intensities. Fast and reliable photoresponse and recovery were observed when CdTe mu Ws were exposed to UV illuminations. We demonstrated that high quality CdTe mu Ws grown by the CSS method have significant potentials as optoelectronic devices. (C) 2013 AIP Publishing LLC.