Anomalous subthreshold current—Voltage characteristics of n-channel SOI MOSFET's

The abnormally high slopes of the subthreshold current-voltage characteristics exhibited by n-channel silicon-on-insulator (SOI) MOSFET's are experimentally related to defect density (off-state leakage current) as well as drain voltage and channel length, and a theoretical physical description of the measured relations is presented and supported. The anomalous subthreshold behavior is attributed analytically to the (floating) body effect due to charging (biasing) by impact ionization at the drain.