Demonstration of a GaN-based P-channel FinFET with high current density based on multi-channel structure

In this work, we report a p-GaN/u-GaN/AlGaN multi-channel structure using δ-doping. The multi-channel structure exhibits a low sheet resistance of 12.9 kΩ/sq. The AlGaN/GaN/AlGaN sandwich structure results in a significant reduction in channel width and a substantial increase in restricted ability for holes. The multi-channel structure has markedly enhanced sheet hole density in comparison to the conventional single-channel structure. Meanwhile, the carriers are distributed in different channels, thereby diminishing the inter-carrier scattering effect. The hole mobility of the multi-channel structure remains largely unaffected by the increased sheet hole density. Due to the excellent conductivity, the ohmic contact resistance of the multi-channel structure is as low as 15.9 Ω mm. Moreover, a p-channel FinFET device was fabricated based on the multi-channel structure. The device exhibits a remarkable high saturation current density of 112 mA/mm, which indicates that the multi-channel structure has potential for high-performance GaN p-channel field effect transistors.