High-Performance Light-assisted Erasable In-Ga-Sn-O (IGTO) Thin-Film Flash Memory Application Annealed at a Low Temperature of 150℃

Abstract

This study first attempted to fabricaate and study the properties of flash memory devices using amorphous IGTO material as the channel material. Compared with devices using amorphous IGZO material as the channel material, amorphous IGTO flash memory devices exhibit improved flash memory devices characteristics withlower threshold voltage(VrH),lower sub-threshold swing (SS), higher fieeld effect mobility (upen) and improved on-current to off-current ratio (IoN/OFF). The erasing methods and possible mechanisms for enhancing erasing efficiency utilizing light-assisted negative gate biasing were discussed in this paper. The photo transition is closely related to the oxygen vacancy, therefore, the light-assisted approach photoionizing oxygen vacancies to generate holes could be a way to achieve erasing under the negative gate bias. Compared with amorphous IGZO material, amorphous IGTO material has lower electron affinity and more oxygen vacancies that can provide more holes. In the program/erase (P/E) characterization under different circumstances, amorphous IGTO devices had a widened memory window (M.W.), and longer retention behaviors.