Silicide-block-film effects on high voltage drain-extended MOS transistors

Abstract

Silicide-block-film effects on drain-extended MOS (DEMOS) transistors were comparatively investigated, by means of different film stack stoichiometric SiO2 and silicon-rich oxide (SRO). The electrical properties of the as-deposited films were evaluated by extracting source/drain series resistance. It was found that the block film plays a role like a field plate, which has significant influence on the electric field beneath. Similar to hot-carrier-injection (HCI) induced degradation for devices, the block film initially charged in fabrication process also strongly affects the device characteristics and limits the safe operating area.