A novel Silicon-On-Insulator (SOI) MOSFET for ultra low voltage operation

To extend the lower bound of power supply voltage, we propose a variable threshold voltage MOSFET (VTMOS) built on silicon-on-insulator (SOI). Threshold voltage of VTMOS drops as gate voltage is raised, resulting in a much higher current drive than regular MOSEET, at low Vdd. On the other hand, V/sub t/ is high at V/sub gs/=O, thus the leakage current is low. The SOI devices used in the study were built on SIMOX wafers. A four terminal layout was used to provide separate source, drain, gate, and body contacts.