[en] Performance of unpassivated MOVPE grown AlGaN/GaN/SiC HEMTs under short-term electrical bias stress isreported. Insignificant degradation in DC and RF behaviour of prepared devices after 16 h stress at VD ¼ 21 V and VG ¼ 2:5 V is observed. This can be demonstrated by a maximum drain current of 1.03 and 1.01 A/mm and a peak extrinsic transconductance of 233 and 225 mS/mm before and after bias stress, respectively. Consecutive drain voltage sweeps indicates on low current collapse in samples investigated. The RF characteristics show a decrease of the fmax-tof T ratio from 2.23 to 2.15 and the saturated output power density measured at 2 GHz from 3.60 to 3.53 W/mm after the devices were stressed. This result indicates that reliable AlGaN/GaN/SiC HEMTs without passivation can be prepared. However, additional studies are needed to understand if the material structure and/or the device processing is responsible for low current collapse and RF dispersion in these devices.
Disciplines :
Electrical & electronics engineering
Identifiers :
UNILU:UL-ARTICLE-2009-358
Author, co-author :
Bernát, J.; Institute of Thin Films and Interfaces (ISG1), Research Centre Jülich, 52425 Jülich, Germany
Wolter, M.; Institute of Thin Films and Interfaces (ISG1), Research Centre Jülich, 52425 Jülich, Germany
Javorka, P.; Institute of Thin Films and Interfaces (ISG1), Research Centre Jülich, 52425 Jülich, Germany
Fox, A.; Institute of Thin Films and Interfaces (ISG1), Research Centre Jülich, 52425 Jülich, Germany
Marso, Michel ; Institute of Thin Films and Interfaces (ISG1), Research Centre Jülich, 52425 Jülich, Germany
Kordoš, P.; Institute of Thin Films and Interfaces (ISG1), Research Centre Jülich, 52425 Jülich, Germany
Language :
English
Title :
Performance of unpassivated AlGaN/GaN/SiC HEMTs after short-term electrical bias stress