Evidence of energetically-localized trap-states at SOI-BOX interface in high-dose SIMOX wafers

Abstract

As the trend in SOI technology continues to be towards thin-film devices, it is important to take a closer look at the electrically active defects at SOI-BOX interface, which could strongly affect the performance and reliability of SOI devices (Cristoloveanu, 1995). Although several studies on the interface trap densities at the SOI-BOX interface of SIMOX wafers have been reported (Nakashima et al, 1998; Yang et al., 1992), comprehensive analysis of these electrically active defects has not yet been fully studied, despite its scientific interest and technological importance. The purpose of this paper is to show for the first time that extraordinary kink effects have been experimentally observed in back-gate transconductance (g/sub m2/) characteristics of fully-depleted (FD) SOI MOS transistors on high-dose SIMOX wafers, and a physical explanation has been found.