Title :
Novel GaAs heterojunction bipolar transistors using In/sub 0.5/Al/sub 0.5/P as emitter
Author :
Kuo, J.M. ; Chen, Y.K.
Author_Institution :
AT&T Bell Labs., Murray Hill, NJ, USA
Abstract :
We report the fabrication and characterization of the first single and double In/sub 0.5/Al/sub 0.5/P/GaAs heterojunction bipolar transistors (HBT´s). These HBT´s are grown by gas-source molecular beam epitaxy. The In/sub 0.5/Al/sub 0.5/P/GaAs heterostructure has the largest valence band discontinuity among all Ill-V semiconductor heterojunctions lattice-matched to GaAs. Common-emitter dc current gains as high as 300 and 400 are measured for SHBT´s and DHBT´s, respectively, with base doping of 1/spl times/10/sup 19/ cm/sup /spl minus/3/. The corresponding offset voltage is 80 and 120 mV, respectively. These results demonstrate the advantages of the In/sub 0.5/Al/sub 0.5/P/GaAs band alignment and make the new HBT´s attractive candidates for high-speed digital circuit applications.<>
Keywords :
III-V semiconductors; aluminium compounds; chemical beam epitaxial growth; gallium arsenide; heterojunction bipolar transistors; indium compounds; semiconductor growth; 120 mV; 80 mV; DHBT; In/sub 0.5/Al/sub 0.5/P-GaAs; SHBT; band alignment; base doping; common-emitter DC current gain; gas-source molecular beam epitaxy; heterojunction bipolar transistors; high-speed digital circuit applications; offset voltage; valence band discontinuity; Current measurement; DH-HEMTs; Digital circuits; Fabrication; Gain measurement; Gallium arsenide; Heterojunction bipolar transistors; Molecular beam epitaxial growth; Semiconductor device doping; Voltage;
Journal_Title :
Electron Device Letters, IEEE