Work

Investigation of Prolonged Negative Threshold Voltage Shift Induced by Low Drain Bias in Schottky p-GaN Gate HEMTs

Year: 2026

Type: article

Abstract: In this work, threshold voltage (V ${}_{\mathrm {th}}$ ) instability was investigated under drain bias stress in Schottky p-GaN gate high electron mobility transistors (HEMTs). A negative shift in threshold voltage was observed under a very low drain bias condition. The negative shift is likely due to an intrinsic donor-like trap state in the p-GaN layer. In contrast, positive shifts in threshold voltage occurred in two distinct phases under higher drain bias stress. With increasing temperature, the initial positive shift was alleviated, while the subsequent positive shift became pronounced during the prolonged stress period. This suggests that multiple mechanisms contribute to the observed positive shifts in threshold voltage. These positive shifts are associated with the Schottky junction barrier and defect state in the GaN buffer layer, respectively.

Source: IEEE Journal of the Electron Devices Society

DOI: 10.1109/jeds.2026.3726880

Authors: Myeongsu Chae, Hyungtak Kim

Institution: Hongik University

Language: English

Topic: GaN-based semiconductor devices and materials

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,350

Funders: Korea Institute for Advancement of Technology, National Research Foundation of Korea, National Research Council of Science and Technology