Impact of interface traps on gate-induced drain leakage current in n-type metal oxide semiconductor field effect transistor

Abstract

As the features sizes of metal oxide semiconductor field effect transistor (MOSFET) are aggressively scaled into the submicron domain, hot carriers generated by the very large electric fields of drain region create serious reliability problems for the integrated circuit in MOS technology. The charges trapping in the gate oxide and the defects at the Si/SiO2 interface have also undesirable effects on the degradation and ageing of MOSFET. Among the problems caused by these effects is the band-to-band tunnelling (BBT) of hot carriers in the gate-to-drain overlap region which is the source of the gate-induced drain leakage current I gidl. The oxide charges shift the flat-band voltage and result in an enhancement of the I gidl current. On the other hand, the generation of interface traps introduce an additional band-trap-band (BTB) leakage mechanism and lead to a significant increase ▵I gidl in a drain leakage current. In this work we propose a new method to calculate the I gidl current which takes into account of the BTB leakage mechanism in order to clarify the impact of interface traps located in the gate-to-drain overlap region on the I gidl current.