Trap-related effects in AlGaAs/GaAs HEMTs

Author

Canali, C. ; Magistrali, F. ; Paccagnella, A. ; Sangalli, M. ; Tedesco, C. ; Zanoni, E.

Author_Institution

Dipartimento di Elettronica e Inf., Padova Univ., Italy

Volume

138

Issue

1

fYear

1991

fDate

2/1/1991 12:00:00 AM

Firstpage

104

Lastpage

108

Abstract

Some AlGaAs/GaAs HEMTs display output resistance and transconductance frequency dispersions that are strongly dependent on the applied drain bias V_DS. These frequency and bias dependences have been observed in devices showing a `kink´ effect in the DC current/voltage characteristics. All such phenomena appear to be closely correlated and, because of the presence of deep levels in the AlGaAs layer, may be correlated to DX centres. Electron trapping and detrapping times, which, at low V_DS, are about 3 and 10 μs, respectively, can be reduced by almost one order of magnitude by an increase in the drain voltage. Consequently, the related frequency-dependent phenomena disappear at frequencies higher than few megahertz

Keywords

III-V semiconductors; aluminium compounds; deep levels; electron traps; gallium arsenide; high electron mobility transistors; AlGaAs-GaAs; DC current/voltage characteristics; DX centres; HEMTs; applied drain bias; bias dependences; deep levels; drain voltage; electron detrapping; electron trapping; frequency dependent effects; frequency-dependent phenomena; kink effect; output-resistance frequency dispersion; transconductance frequency dispersions; trap-related effects;

fLanguage

English

Journal_Title

Circuits, Devices and Systems, IEE Proceedings G

Publisher

iet

ISSN

0956-3768

Type

jour

Filename

87819