Characteristics of AgInSbTe-SiO2 nanocomposite thin film applied to nonvolatile floating gate memory devices

Abstract

Nanocomposite thin films containing AgInSbTe (AIST) particles embedded in an SiO2 matrix was prepared by sputtering deposition and its feasibility for nonvolatile floating gate memory (NFGM) was investigated. The sample subjected to a 400 degrees C annealing exhibited a distinct hysteresis memory window (Delta V-FB) shift = 6.6 V and charge density = 5.2 x 10(12) cm(-2) after +/- 8 V gate voltage sweep. Electrical measurement revealed the current transport is via the Schottky emission in low applied field and the space-charge-limited conduction mechanism in high applied field in the samples, regardless of their thermal history. Transmission electron microscopy and x-ray photoelectron spectroscopy indicated that the metallic Sb2Te nanocrystals (NCs) with diameters about 5-7 nm dispersed in a nanocomposite layer may serve as the discrete charge-storage traps for nonvolatile memory. Analytical results illustrate the utilization of an AIST-SiO2 nanocomposite layer as the core structure of NFGM devices is able to simplify the device structure and fabrication process.