Analysis of sense margin and reliability of 1T-DRAM fabricated on thin-film UTBOX substrates

摘要

The floating body RAM is a very promising candidate for further downscaling of memory cells [1,2]. Amongst the different SOI-based device architectures, Ultra-Thin BOX (UTBOX) SOI devices have gained a lot of interest recently [3]. As the buried oxide (BOX) thickness is scaled down, a low-voltage back bias can be used to increase the sense margin. In this work, we will first discuss the impact of back biasing on the sense margin in both doped and undoped devices. As the floating body memory cell requires the use of impact ionization or Gate Induced Drain Leakage (GIDL) [4] to program state "1", reliability is a concern. Therefore, the second part of this paper will be devoted to the reliability study.