Self-aligned SiGe NPN transistors with 285 GHz f MAX and 207 GHz f T in a manufacturable technology

B. Jagannathan, M. Khater, F. Pagette, J. S. Rieh, D. Angell, H. Chen, J. Florkey, F. Golan, D. R. Greenberg, R. Groves, S. J. Jeng, J. Johnson, E. Mengistu, K. T. Schonenberg, C. M. Schnabel, P. Smith, A. Stricker, D. Ahlgren, G. Freeman, K. SteinS. Subbanna

Research output: Contribution to journalLetterpeer-review

258 Citations (Scopus)


This paper reports on SiGe NPN HBTs with unity gain cutoff frequency (f T) of 207 GHz and an f MAX extrapolated from Mason's unilateral gain of 285 GHz. f MAX extrapolated from maximum available gain is 194 GHz. Transistors sized 0.12 × 2.5 μm 2 have these characteristics at a linear current of 1.0 mA/μm (8.3 mA/μm 2). Smaller transistors (0.12 × 0.5 μm 2) have an f T of 180 GHz at 800 μA current. The devices have a pinched base sheet resistance of 2.5 kΩ/sq. and an open-base breakdown voltage BV CEO of 1.7 V. The improved performance is a result of a new self-aligned device structure that minimizes parasitic resistance and capacitance without affecting f T at small lateral dimensions.

Original languageEnglish
Pages (from-to)258-260
Number of pages3
JournalIEEE Electron Device Letters
Issue number5
Publication statusPublished - 2002 May
Externally publishedYes


  • Germanium
  • Heterojunction bipolar transistors (HBTs)
  • High-speed devices
  • SiGe
  • Silicon

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering


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