Title :
Low-frequency properties of lattice matched and strained InGaAs/InAlAs HEMTs
Author :
Ng, G.I. ; Reynoso, A. ; Oh, J.E. ; Pavlidis, D. ; Graffeuil, J. ; Bhattacharya, P.K. ; Weiss, M. ; Moore, K.
Author_Institution :
Michigan Univ., Ann Arbor, MI, USA
Abstract :
The low-frequency characteristics of lattice-matched (x=0.53) and strained (0.60⩽x⩽0.70) Inx Ga1-xAs/InAlAs HEMTs (high-electron-mobility transistors) are studied. Low-frequency noise measurements reveal shallow traps of 0.078 eV to 0.18 eV which have a slight dependence on In composition. The input noise spectra are almost insensitive to In percentage, but the output spectra suggest that the noise increases with strain. This is related to the increase of device gain with In composition and indicates that a compromise has to be made between high gain (large excess In %) and low noise (low excess In %). Transconductance dispersion is observed only under large gate bias and is absent when the device is biased for maximum gm. Trap densities seem to be largest for lattice-matched devices and minimum for 60% In channels
Keywords :
III-V semiconductors; aluminium compounds; electron device noise; gallium arsenide; high electron mobility transistors; indium compounds; semiconductor device testing; In composition; InGaAs-InAlAs; LF noise; device gain; high-electron-mobility transistors; input noise spectra; large gate bias; lattice matched HEMTs; low-frequency characteristics; output spectra; shallow traps; strained HEMTs; transconductance dispersion; trap densities; Contracts; Frequency; Gallium arsenide; HEMTs; Indium compounds; Indium gallium arsenide; Lattices; Low-frequency noise; MODFETs; Transconductance;
Conference_Titel :
High Speed Semiconductor Devices and Circuits, 1989. Proceedings., IEEE/Cornell Conference on Advanced Concepts in
Conference_Location :
Ithaca, NY
DOI :
10.1109/CORNEL.1989.79823
