ON-State Human Body Model ESD Failure Mechanisms in GaN-on-Si RF MIS-HEMTs

Gallium nitride (GaN)-on-Si technologies for advanced RF applications have been raising the attentions in semiconductor industries, which accompany with RF electrostatic discharge (ESD) reliability challenges. Both positive and negative ESD stress polarities are equally important to be investigated. Four scenarios of the positive and negative human body model (HBM) stresses on a gate-tied-to-source configuration (GS (MIS-HEMT)) and a gate-tied-to-drain configuration (GD(MIS-HEMT)) were conducted in GaN-on-Si (MIS-HEMTs). A failure mechanism unveiled in the negative GS MIS-HEMT which is different from the constant-power 2DEG failure mechanism in the typical positive GS (MIS-HEMT), was demonstrated by the measured HBM transient I-V characteristics and the subsequent DC I-V traces. The specific ON-state failure mechanism is related to the constant-voltage gate dielectric failures, resulting from a unique HBM discharge mechanism without the existence of depletion region in the 2DEG channel. This causes the degradation of the HBM failure voltages on the devices. Thus, the lower HBM failure powers are required to destroy the gate dielectric layer, as compared to the high failure powers to induce the 2DEG burnouts.