A new non-volatile memory cell based on the flash architecture for embedded low energy applications: ATW (Asymmetrical Tunnel Window)

Abstract

In this paper we propose a new non-volatile charge trap memory architecture implemented on 200mm wafer in 90nm technology node. The aim of this work is to investigate an alternative and scalable solution for embedded low energy applications. The Asymmetrical Tunnel Window (ATW) memory cell has been developed in order to improve the programming operation during a hot carrier injection. The main property of this device is the presence of an asymmetrical tunnel oxide thickness along the channel. This characteristics enables an improvement in terms of current consumption and injection efficiency with respect to the standard Flash floating gate memory cell. In this work we describe the fabrication process of ATW memory cell and, using a commercial TCAD simulator and experimental results, we demonstrate the good functioning of our device thanks to the increased control gate/floating gate (CG/FG) coupling factor. To conclude we confirm the reliability performances with the endurance experiments up to 100k cycles.