Title :
AlGaAs/Ge/GaAs heterojunction bipolar transistors grown by molecular beam epitaxy
Author :
Strite, Samuel ; Ünlü, M.S. ; Adomi, K. ; Gao, G.-B. ; Morkoç, Hadis
Author_Institution :
Coordinated Sci. Lab., Illinois Univ., Urbana, IL, USA
fDate :
5/1/1990 12:00:00 AM
Abstract :
An N-Al/sub 0.22/Ga/sub 0.78/As emitter, p-Ge base, and n-GaAs collector (AlGaAs/Ge/GaAs) heterojunction bipolar transistor (HBT) in the emitter-up configuration grown by molecular beam epitaxy is discussed. Devices exhibited common-emitter current gains of as high as 300 at a collector current density of 2000 A/cm/sup 2/ and a collector voltage of 4 V. As the device area is reduced from 50*50 to 10*40 mu m, the current gain did not show significant changes, suggesting a low surface recombination velocity in the Ge base.<>
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; germanium; heterojunction bipolar transistors; molecular beam epitaxial growth; semiconductor epitaxial layers; 4 V; AlGaAs-Ge-GaAs; collector current density; collector voltage; common-emitter current gains; device area; emitter-up configuration; heterojunction bipolar transistors; molecular beam epitaxy; surface recombination velocity; Current density; Epitaxial growth; Gallium arsenide; Heterojunction bipolar transistors; Laboratories; Molecular beam epitaxial growth; Photonic band gap; Radiative recombination; Surface resistance; Voltage;
Journal_Title :
Electron Device Letters, IEEE
