Gate and barrier layer design of E-mode GaN HEMT with p-GaN gate structure

Excellent material properties of gallium nitride (GaN) make it have broad application prospects in the fields of medium and low voltage consumer power, new energy vehicles, charging piles. The conventional GaN high electron mobility transistor (GaN HEMT) is in the ON-state at zero gate bias, which is inconsistent with the actual application requirements. So the regulation of the threshold voltage of GaN devices is currently the research hotspot. Among the existing methods, the p-GaN structure is relatively mature and has been applied in practical products, but there are still many problems in related research. This paper mainly studies the influence of some structural parameters of the device on its threshold voltage and saturation current. The structural parameters considered in this paper mainly include the barrier layer Al composition and the length of the p-GaN layer. The breakdown characteristics of the device after optimizing the structural parameters are simulated. The optimized device threshold voltage is 1.4V and the breakdown voltage is 650V.