Investigation of Non Volatile AlGaN/GaN Flash Memory for High Temperature Operation

A charge trap flash (CTF) memory based on AlGaN / GaN transistors has been proposed for memory development in high temperature environment. The proposed device is designed to have a positive threshold voltage for applying NAND or NOR arrays. In order to improve the electron storage ability at high temperature, various dielectrics have been applied. The height of the electron barrier inside the charge trap layer is the most important parameter in the high temperature memory operation and the dielectrics such as Ta2O5 or SrTiO3 shows excellent reliability at 500K. As the temperature increases, a change in threshold voltage occurs, and additional circuitry is needed to compensate for this. Through this paper, design guideline of memory operating in extreme high temperature environment is investigated.