Title :
Planar AlGaAs/GaAs heterojunction bipolar transistors fabricated using selective W-CVD
Author :
Mitani, K. ; Masuda, H. ; Mochizuki, K. ; Kusano, C.
Author_Institution :
Hitachi Ltd., Tokyo, Japan
fDate :
4/1/1992 12:00:00 AM
Abstract :
The authors describe a planar process for the AlGaAs/GaAs HBTs in which collector vias are buried selectively, even to the base layers, with chemical vapor deposited tungsten (CVD-W) films. By using WF/sub 6//SiH/sub 4/ chemistry, W could be deposited on Pt films, which were overlapped 50 nm thick on the AuGe-based collector electrodes, without depositing W on the surrounding SiO/sub 2/ layers. Current gains of planar HBTs with 3.5- mu m*3.5- mu m emitters were up to 150, for a collector current density of about 2.5*10/sup 4/ A/cm/sup 2/.<>
Keywords :
III-V semiconductors; aluminium compounds; chemical vapour deposition; gallium arsenide; heterojunction bipolar transistors; metallisation; semiconductor technology; tungsten; AlGaAs-GaAs; SiO/sub 2/ layers; W-Pt-AuGe; WF/sub 6/; WF/sub 6/-SiH/sub 4/ chemistry; collector current density; collector vias; current gains; heterojunction bipolar transistors; planar HBT; selective CVD; Chemistry; Electrodes; Epitaxial layers; Etching; Fabrication; Gallium arsenide; Heterojunction bipolar transistors; Resists; Surface morphology; Wiring;
Journal_Title :
Electron Device Letters, IEEE
