Impact of undoped channel thickness and carbon concentration on AlN/GaN-on-SiC HEMT performances. (1st November 2022)

• Record Type: Journal Article
• Authors: Harrouche, Kathia; Venkatachalam, Srisaran; Grandpierron, François; Okada, Etienne; Medjdoub, Farid
• Is Part Of: Applied physics express. Volume 15:Number 11(2022)
• Publication Date: 2022-11-01
• Subjects: GaN -- HEMTs -- power added efficiency -- millimeter-wave -- power; Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.35848/1882-0786/ac9c46
• Languages: English
• ISSNs: 1882-0778

Abstract

Abstract: We report on a vertically scaled AlN/GaN high electron mobility transistor technology design optimization for millimeter-wave applications. The undoped GaN channel thickness and carbon concentration into the buffer are extensively varied and systematically characterized. It is found that a thin GaN channel, typically below 150 nm improves the electron confinement, but increases the trapping effects, especially when using shorter gate lengths. Moreover, high carbon concentration into the buffer enables not only high electron confinement but also low leakage current under a high electric field at the expense of trapping effects. As a result, the optimum epi-design enabled state-of-the-art RF performances at 40 GHz.