Gate-Induced-Drain-Leakage (GIDL) in CMOS Enhanced by Mechanical Stress

Abstract

The impact of mechanical stress (MS) on MOSFET gate-induced drain leakage (GIDL) current is investigated. The tests were performed on planar short-channel p- and n-type MOSFETs. Vertical compressive MS was induced in the devices by applying a vertical load with a nanoindenter. The applied stress was ranging from several hundred MPa to a GPa range, estimated by finite-element modeling. It is reported that GIDL current increases exponentially with MS. This effect is attributed to MS-induced reduction in the silicon bandgap and effective mass, leading to enhanced band-to-band tunneling (BTBT). Furthermore, the GIDL currents are found to change depending on the location where the vertical force is applied, with a higher influence of force on GIDL above the channel.