Title :
InP-InAlAs and InGaP-InAlAs mixed spacers to reduce the gate leakage current in InAlAs/InGaAs/InP HEMTs
Author :
Letartre, X. ; Rojo-Romeo, P. ; Tardy, J. ; Gendry, M. ; Thompson, D. ; Simmons, J.G.
Author_Institution :
Lab. d´´Electron., Ecole Centrale de Lyon, Ecully, France
Abstract :
In this work, we propose a comparative study of the behaviour of three HEMT structures at high reverse bias: a reference structure (S1) with a conventional InAlAs spacer, the second with an InP/InAlAs mixed spacer (S2) and the third with an In0.5Ga0.5P/InAlAs (S3) mixed spacer. We show a drastic decrease of the gate leakage current for the mixed spacer HEMTs, thanks to the large valence band offset between InP (or InGaP) and InGaAs. Moreover, Low Frequency Noise (LFN) measurements were performed to investigate the defect distribution in the three structures. These help us to distinguish between the transport mechanisms which govern the gate leakage current
Keywords :
Hall effect; III-V semiconductors; aluminium compounds; electric breakdown; gallium arsenide; high electron mobility transistors; impact ionisation; indium compounds; leakage currents; semiconductor device noise; Hall measurements; In0.5Ga0.5P-InAlAs; InAlAs-InGaAs-InP; InAlAs/InGaAs/InP HEMTs; InP; InP-InAlAs; breakdown voltage; defect distribution; gate leakage current; high reverse bias; impact ionization; low frequency noise measurements; mixed spacers; transport mechanisms; valence band offset; Etching; HEMTs; Helium; Indium compounds; Indium gallium arsenide; Indium phosphide; Leakage current; MODFETs; Molecular beam epitaxial growth; Surface treatment;
Conference_Titel :
Indium Phosphide and Related Materials, 1997., International Conference on
Conference_Location :
Cape Cod, MA
Print_ISBN :
0-7803-3898-7
DOI :
10.1109/ICIPRM.1997.600166
