Non-volatile semiconductor memory device and method of manufacturing the same

摘要

A non-volatile memory device is fabricated having enhanced charge retention capability. Enhanced charge retention is achieved upon the floating gate of the non-volatile memory device. The floating gate can configured as a stacked or non-stacked pair of polysilicon conductors. In either instance, negative charge programmed upon the floating gate is retained by reducing the presence of positively charged atoms within dielectrics overlying the floating gate conductor. Moreover, diffusion avenues of the positively charged hydrogen are reduced by maintaining a prevalence of relatively strong bond locations within the overlying dielectric layers. Thus, origination of positively charged atoms such as hydrogen from those bonds are substantially prevented by processing the hydrogen-containing dielectrics at relatively low temperatures and further processing any subsequent dielectrics and/or conductors overlying the floating gate at relatively low temperatures. Suitable processing temperatures (dielectric deposition and metal sintering temperatures) are temperatures less than 380 DEG C.