Dual Material Gate Tunnel Field Effect Transistor based Dopingless 1T DRAM

Abstract

A dopingless 1 transistor Dynamic Random Access Memory based on tunnel field effect transistor with dual material gate is proposed. This proposed DRAM structure shows considerable improvement in sense margin and retention time when compared with the 1T DRAM structure with double gate TFET. The current in read operation depends on the work function of source, drain and both gates. The ON current gets enhanced and OFF current becomes very low with the incorporation of dual material gate. Thus the sense margin and retention time of DRAM is improved. 2D device simulations are done with Silvaco Atlas TCAD tool. The sense margin was found out to be 31.5 nA and a retention time is 275 ms. The proposed device delivers a good trade off between sense margin and retention time. Random dopant fluctuation will not affect the performance of DRAM as it is a dopingless structure. The damages caused by ion implantation can be avoided and this makes DRAM more reliable.