On the defects introduced by AC and DC hot carrier stress in SOI PD MOSFETs

The defects introduced by hot carrier stress during on-state operation (DC stress) and dynamic operation (AC stress), ofUnibond SOI MOSFETs (0.25μm gate length), are investigated. These defects are monitored by means of Deep Level Transient Spectroscopy (DLTS) technique, which is based on drain current transient signal recording. DLTS spectra of devices subjected to hot carrier stress revealed the presence of traps, some of which were previously reported in literature. Transient effects such as overshoot/undershoot, presented at DLTS spectra of partially depleted SOI devices, was overcome by using body contacted devices. The latter were studied further in order to monitor the body potential transients and to emerge information about the body excess charge recombination paths.