Experimental Demonstration of n- and p-channel GaN-MOSFETs toward Power IC Applications

We report on the systematic demonstrations of the depletion-mode p-channel and enhancement-mode n-channel GaN metal-oxide field-effect transistors (MOSFETs) based on homoepitaxial p-GaN substrates. The world's first depletion-mode p-channel GaN-MOSFET fabricated in this work shows a good Ion/Ioff characteristic (similar to 10(4)) and an effective channel hole mobility of approximately 0.2 cm(2)/V center dot s at room temperature. For the first time, it is proved that the p-channel GaN-MOSFETs can work independently without the necessity of two-dimension hole gas (2DHG) sources of heterostructures. Meanwhile, the maximum effective electron mobility of n-channel GaN-MOSFETs is approximately 10(5) cm(2)/V center dot s. The post deposition annealing (PDA) treatment of Al2O3 dielectrics is also verified in both n and p-channel GaN-MOSFETs and 700 degrees C is found to be the optimized condition on improving the effective hole/electron mobility. The findings in this work provide a valuable information in the design of novel power electronics taking advantage of p-type doped GaN. (c) The Author(s) 2019. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited.