Title :
Experimental I-V characteristics of AlGaAs/GaAs heterojunction bipolar transistors with very thin bases
Author :
Hsin, Y.M. ; Vu, D.P. ; Asbeck, P.M.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., San Diego, La Jolla, CA
fDate :
7/4/1996 12:00:00 AM
Abstract :
Npn abrupt AlGaAs/GaAs heterojunction bipolar transistors with thin base widths (WB) down to 200 Å have been fabricated for the first time, and their collector and base current-voltage characteristics have been studied. The experimental results show that the surface recombination base current and the base bulk recombination current are both significantly lower in 200 Å base HBTs than in comparable devices with 500 Å base width. For the thin base HBTS, the base bulk recombination current density is proportional to ~WB and the surface recombination current density is proportional to ~WB2. The experiment also showed that the collector current across a thin p+ GaAs base is limited, as expected, by the thermal velocity of the electrons rather than by conventional diffusive transport
Keywords :
III-V semiconductors; aluminium compounds; characteristics measurement; electron-hole recombination; gallium arsenide; heterojunction bipolar transistors; semiconductor device testing; surface recombination; 200 angstrom; AlGaAs-GaAs; I-V characteristics; base bulk recombination current; base widths; collector current; heterojunction bipolar transistors; surface recombination base current; thermal velocity; very thin bases;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19960853
