Effect of Nitrogen Incorporation to AgInSbTe-SiO2 Nanocomposite Thin Films Applied to Nonvolatile Floating Gate Memory

Abstract

Nonvolatile floating gate memory devices containing AgInSbTe-SiO2 nanocomposites as the charge trapping layers prepared by target-attached sputtering method at various nitrogen incorporation conditions were investigated. The nitrogen incorporation was found to be essential to the nonvolatile memory characteristics and a significant memory window (Delta V-FB) shift = 6.9 V and charge density = 7.1 x 10(12) cm(-2) at +/- 8 V gate voltage sweep could be obtained in the sample with satisfied charge retention property. Transmission electron microscopy revealed the nanocomposite layers contain Sb-2 Te nanocrystals about 5 nm in diameter which may serve as the charge storage traps of memory devices. X-ray photoelectron spectroscopy indicated nitrogen incorporation may alleviate the oxidation of AIST phase and promote the reduction of antimony oxide to form metallic Sb-2 Te phase in nanocomposite layers, leading to the good nonvolatile memory characteristics of NFGM device containing the AIST-SiO2 nanocomposite as the charge-storage trap layer.