A thorough investigation of hot-carrier-induced gate oxide breakdown in partially depleted N- and P-channel SIMOX MOSFETs

Abstract

In this paper, the hot-carrier-injected oxide region in the front interfaces is systematically investigated for partially depleted silicon-on-insulator (PDSOI) metal-oxide-semiconductor field-effect transistors (MOSFETs) devices fabricated on a SIMOX wafer. The gate oxide properties associated with channel hot-carrier effects are investigated and the hot-carrier-induced device degradations are analyzed using stress experiments with three main types of hot-carrier injections-maximum gate current, maximum substrate current and parasitic bipolar transistor action. Based on experimental results, the influence of these injected carriers on the gate oxide properties is clarified. As a matter of fact, NMOSFETs degradation mechanism is shown to be caused by hot holes injected into the drain side of the gate oxide, and electrons trapped in the gate oxide can accelerate the gate oxide breakdown. PMOSFETs degradation mechanism depends on the biasing conditions. For the first time, we conclude that the electrical characteristics of NMOSFETs are significantly different from that of PMOSFETs after the gate oxide breakdown. An extensive discussion of the experimental results is provided.