The self-heating and high-power microwave (HPM) effects that can cause device heating are serious reliability issues for gallium nitride (GaN) high-electron-mobility transistors (HEMT), but the specific mechanisms are disparate. The different impacts of the two effects on enhancement-mode p-gate AlGaN/GaN HEMT are first investigated in this paper by simulation and experimental verification. The simulation models are calibrated with previously reported work in electrical characteristics. By simulation, the distributions of lattice temperature, energy band, current density, electric field strength, and carrier mobility within the device are plotted to facilitate understanding of the two distinguishing mechanisms. The results show that the upward trend in temperature, the distribution of hot spots, and the thermal mechanism are the main distinctions. The effect of HPM leads to breakdown and unrecoverable thermal damage in the source and drain areas below the gate, while self-heating can only cause heat accumulation in the drain area. This is an important reference for future research on HEMT damage location prediction technology and reliability enhancement.

The reliability of the integrated circuits (ICs) has become one of the greatest challenges with the increasing complexity of the electromagnetic environment. On this basis, an explicit difference in the damage location is observed in the high-power microwave (HPM) radiated CMOS inverters. The detailed damage mechanism analysis is performed. The analysis shows that the overcurrent-dominant failure and the latch-up-dominant failure are induced in positive and negative half radiation cycle respectively, resulting in the damage location discrepancy. The depletion region current $I_{\textrm {SS}}$ and the body current $I_{\textrm {body}}$ are derived from the established theoretical charge transport model. TCAD simulations demonstrate the junctional-overcurrent and latch-up process, empirical formula is obtained to explain the damage mechanism and predict the thermal damage location. The damage dependency on interference characteristics is discussed for further understanding. Corresponding experiments are performed using the six-integrated-inverters chip. The results support the theoretical charge transport model well.