RF and DC Analysis of Stressed InGaAs MOSFETs

A complete reliability study of the DC and RF characteristics for InGaAs nMOSFETs with aluminium oxide/ hafnium oxide dielectric is presented. The main stress variation at high frequencies is related to a threshold voltage shift, whereas no decrease is found in the maximum of the cut-off frequency and RF-transconductance. Constant gate stress leads to a charge build up causing a threshold voltage shift. Furthermore, electron trapping at the drain side degrades the performance after hot carrier stress. The maximum DC-transconductance is reduced following constant gate bias stress, by an increase in charge trapping at border defects. These border defects at the channel/high-k interface are filled by cold carrier trapping when the transistor is turned on, whereas they do not respond at high frequencies.