Title :
A 183 GHz fT and 165 GHz fmax regrown-emitter DHBT with abrupt InP emitter
Author :
Scott, D.W. ; Yun Wei ; Yingda Dong ; Gossard, A.C. ; Rodwell, M.J.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., USA
fDate :
6/1/2004 12:00:00 AM
Abstract :
Small-area regrown emitter-base junction InP/In-GaAs/InP double heterojunction bipolar transistors (DHBT) using an abrupt InP emitter are presented for the first time. In a device with emitter-base junction area of 0.7 × 8 μm2, a maximum 183 GHz fT and 165 GHz fmax are exhibited. To our knowledge, this is the highest reported bandwidth for a III-V bipolar transistor utilizing emitter regrowth. The emitter current density is 6×105 A/cm2 at V/sub CE,sat/ = 1.5 V. The small-signal current gain h/sub 21/ = 17, while collector breakdown voltage is near 6 V for the 1500-/spl Aring/-thick collector. The emitter structure, created by nonselective molecular beam epitaxy regrowth, combines a small-area emitter-base junction and a larger-area extrinsic emitter contact, and is similar in structure to that of a SiGe HBT. The higher fT and fmax compared to previously reported devices are achieved by simplified regrowth using an InP emitter and by improvements to the regrowth surface preparation process.
Keywords :
III-V semiconductors; current density; heterojunction bipolar transistors; indium compounds; molecular beam epitaxial growth; semiconductor heterojunctions; 165 GHz; 183 GHz; III-V bipolar transistor; InP-InGaAs-InP; abrupt InP emitter; collector breakdown voltage; double heterojunction bipolar transistors; emitter current density; emitter regrowth; emitter structure; emitter-base junction; epitaxial growth; extrinsic emitter contact; nonselective molecular beam epitaxy regrowth; regrown-emitter DHBT; regrowth surface preparation process; small-signal current gain; Bandwidth; Bipolar transistors; Current density; Double heterojunction bipolar transistors; Germanium silicon alloys; Heterojunction bipolar transistors; III-V semiconductor materials; Indium phosphide; Molecular beam epitaxial growth; Silicon germanium;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2004.829667
