Parameter Shift of Quasi-Vertical GaN-on-Si Schottky Barrier Diodes Under On-State Forward-Current (24 kA/cm(2)) Stress

In this article, we carry out the parameter shift of quasi-vertical GaN-on-Si Schottky barrier diodes (SBDs) under ON-state stress with a high forward current of 2-4 kA/cm(2). Turn-on voltage Von, (ON)-resistance R-ON, reverse leakage current Ireverse, Schottky barrier height f, and ideality factor n were monitored during the ON-state stress. From semilog scale, all the subthreshold leakage currents increase evidently for a stress voltage of 5 V and a stress time of 50-1000 s. Most of the extracted Von are nearly unchanged for all the 2.5-4.5-V stress and decrease by -0.065 to -0.085 V for 5-V/50-1000-s stress. RON first increases and then decreases, and the maximum RON shift is only 3.8%. The stressed devices are measured 24 h after the stress, and it is found that RON shift under highcurrent stress is recoverable. The reverse leakage current increases from 2.97 x 10(-3) to 7.93 x 10(-3) A/cm(2) at a reverse bias of -100 V after 5-V/1000-s stress. The corresponding f decreases from 0.82 to 0.53-0.58 eV, and n is increased from 1.03 to 1.87-2.57, indicating the parameter shift occurs at the anode/n-GaN interface. Experiments and analysis demonstrate that the device characteristics of quasi-vertical GaN-on-Si SBDs can be degraded to a certain extent under high-current/long-time stress.