Title :
A submicrometer 252 GHz fT and 283 GHz fmax InP DHBT with reduced C/sub BC/ using selectively implanted buried subcollector (SIBS)
Author :
Li, J.C. ; Chen, M. ; Hitko, D.A. ; Fields, C.H. ; Binqiang Shi ; Rajavel, R. ; Asbeck, P.M. ; Sokolich, M.
Author_Institution :
HRL Labs., Malibu, CA, USA
fDate :
3/1/2005 12:00:00 AM
Abstract :
The selectively implanted buried subcollector (SIBS) is a method to decouple the intrinsic and extrinsic C/sub BC/ of InP-based double-heterojunction bipolar transistors (DHBTs). Similar to the selectively implanted collector (SIC) used in Si-based bipolar junction transistors (BJTs) and HBTs, ion implantation is used to create a N+ region in the collector directly under the emitter. By moving the subcollector boundary closer to the BC junction, SIBS allows the intrinsic collector to be thin, reducing /spl tau//sub C/, while simultaneously allowing the extrinsic collector to be thick, reducing C/sub BC/. For a 0.35 × 6 μm2 emitter InP-based DHBT with a SIBS, 6 fF total C/sub BC/ and >6 V BV/sub CBO/ were obtained with a 110-nm intrinsic collector thickness. A maximum fT of 252 GHz and fmax of 283 GHz were obtained at a V/sub CE/ of 1.6 V and I/sub C/ of 7.52 mA. Despite ion implantation and materials regrowth during device fabrication, a base and collector current ideality factor of /spl sim/2.0 and /spl sim/1.4, respectively, at an I/sub C/ of 100 μA, and a peak dc /spl beta/ of 36 were measured.
Keywords :
III-V semiconductors; heterojunction bipolar transistors; indium compounds; ion implantation; molecular beam epitaxial growth; InP; Si; bipolar junction transistors; device fabrication; double heterojunction bipolar transistors; ion implantation; materials regrowth; molecular beam epitaxy; selectively implanted buried subcollector; selectively implanted collector; Bipolar transistors; CMOS technology; Doping; Germanium silicon alloys; Implants; Indium phosphide; Ion implantation; Molecular beam epitaxial growth; Silicon carbide; Silicon germanium; Heterojunction bipolar transistors (HBTs); InP; ion implant; molecular-beam epitaxy (MBE);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2004.842734