Effect of Nitrogen Incorporation to $\hbox {AgInSbTe-SiO}_{2}$ Nanocomposite Thin Films Applied to Nonvolatile Floating Gate Memory

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 (ΔV_FB) shift = 6.9 V and charge density = 7.1 × 10¹² 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 Sb₂Te 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 Sb₂Te 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.