Deposition and characterization of CVD-grown Ge-Sb thin film device for phase-change memory application

Abstract

Germanium antimony (Ge-Sb) thin films with tuneable compositions have been fabricated on SiO2/Si, borosilicate glass, and quartz glass substrates by chemical vapour deposition (CVD). Deposition takes place at atmospheric pressure using metal chloride precursors at reaction temperatures between 750 and 875 °C. The compositions and structures of these thin films have been characterized by micro-Raman, scanning electron microscope (SEM) with energy dispersive X-ray analysis (EDX), and X-ray diffraction (XRD) techniques. A prototype Ge-Sb thin film phase-change memory device has been fabricated and reversible threshold and phase change switching demonstrated electrically, with a threshold voltage of 2.2 - 2.5 V. These CVD-grown Ge-Sb films show promise for applications such as phase change memory and optical, electronic and plasmonic switching.