Role of the AlGaN barrier on the long-term gate reliability of power HEMTs with p-GaN gate. (November 2020)

• Record Type: Journal Article
• Authors: Tallarico, A.N.; Posthuma, N.E.; Bakeroot, B.; Decoutere, S.; Sangiorgi, E.; Fiegna, C.
• Is Part Of: Microelectronics and reliability. Volume 114(2020)
• Publication Date: 2020-11
• Subjects: Electronic apparatus and appliances -- Reliability -- Periodicals; Miniature electronic equipment -- Periodicals; Appareils électroniques -- Fiabilité -- Périodiques; Équipement électronique miniaturisé -- Périodiques; Electronic apparatus and appliances -- Reliability; Miniature electronic equipment; Periodicals; 621.3815
• DOI: 10.1016/j.microrel.2020.113872
• Languages: English
• ISSNs: 0026-2714

Abstract

Abstract: Forward gate constant voltage stress (CVS) has been performed on GaN-on-Si (200 mm) HEMTs with p-GaN gate, controlled by a Schottky metal-retracted/p-GaN junction, processed by imec with different gate process splits. In particular, the adoption of devices with a different magnesium (Mg) concentration in the p-GaN layer, AlGaN barrier thickness and AlGaN aluminium percentage (Al%), allowed us to identify the degradation of the AlGaN barrier as responsible for time-dependent gate breakdown at room temperature. Lowering the Al% of the barrier and the Mg concentration of the p-GaN layer leads to a longer gate lifetime, while an optimum AlGaN barrier thickness is identified at given Al%.