Crystallized silicon-on-insulator nonvolatile memory device

TLDR: In this paper, a nonvolatile memory device is presented, which utilizes a laser beam recrystallized silicon layer having source-channel-drain regions, where a gate is formed directly on a substrate of an insulative material (e.g. non-silicon material).

Abstract: Disclosed is a nonvolatile memory device which utilizes a laser beam recrystallized silicon layer having source-channel-drain regions. Underlying the recrystallized layer and separated therefrom by a memory dielectric is a gate in alignment with the source and drain. The gate is formed directly on a substrate of an insulative material (e.g. non-silicon material). The process of forming the above device comprises forming a conductive polysilicon gate on a substrate followed by a memory nitride layer deposition thereon. A thick oxide layer is formed over the nitride followed by removal of the thick oxide corresponding to a central portion of the gate thereby exposing the nitride therebeneath. The exposed nitride surface is thermally converted into a thin, stoichiometric memory SiO2. A doped polysilicon layer is then formed on the structure and thereafter converted to recrystallized silicon by subjecting it to laser radiation. The recrystallized silicon is patterned into the device active area and a source and drain in alignment with the underlying gate are implanted therein.