[en] The influence of a substrate voltage on the dc characteristics of an AlGaN/GaN HEMT on silicon (111) substrate is investigated. This effect, known as backgating, is used to study traps that are located between substrate and 2DEG channel. The transient of the drain current after applying a negative substrate voltage is evaluated for measurements with and without illumination. Several trap contributions are resolved by measurements at different photon energies. A photocurrent is observed up to 600 nm wavelength. Up to this wavelength the backgating effect can be compensated and the drain current restored by a short light pulse. The experiments are performed on completed HEMTs, allowing investigation of the influence of device fabrication technology.
Disciplines :
Electrical & electronics engineering
Identifiers :
UNILU:UL-ARTICLE-2009-343
Author, co-author :
Marso, Michel ; Institute of Thin Films and Interfaces, Research Centre Jülich, 52425 Jülich, Germany
Wolter, M.; Institute of Thin Films and Interfaces, Research Centre Jülich, 52425 Jülich, Germany
Javorka, P.; Institute of Thin Films and Interfaces, Research Centre Jülich, 52425 Jülich, Germany
