High performance Silicon-On-ONO (SOONO) Cell Array Transistors (SCATs) for 512Mb DRAM Cell Array Application

As DRAM cell pitch size scales, the DRAM cells have required characteristics of high performance transistors. In this paper, we proposed and successfully demonstrated high performance silicon-on-ONO (SOONO) cell array transistors (SCATs) for 512Mb DRAM cell array application. They have advantages of SOI substrate and 3-D hi-gate as well as process simplicity. From those advantages, they have low Ioff due to good SCE immunity with DIBL of 40 mV/V and SS of 84 mV/dec, low GIDL current, low junction leakage current, and low junction capacitance as well as no body bias dependence. Thus, the SCATs may be a promising solution satisfying the requirements of DRAM cells with scaling.