• DocumentCode
    1283783
  • Title

    Base transit time for SiGe-base heterojunction bipolar transistors

  • Author

    Gao, G.-B. ; Morkoc, H.

  • Author_Institution
    Coordinated Sci. Lab., Illinois Univ., Urbana, IL, USA
  • Volume
    27
  • Issue
    16
  • fYear
    1991
  • Firstpage
    1408
  • Lastpage
    1410
  • Abstract
    The base transit time expressions for SiGe base heterojunction bipolar transistors are presented including the accelerating field effects due to the base bandgap grading and doping grading, and the retarding field (opposing drift field) effect from the graded boron profile down towards the emitter. It is found that the retarding field exhibits 40-80% contribution to the base transit time, depending on the boron concentration near the emitter. The results of base transit time from these analytic expressions are unambiguously supported by the published simulation data.
  • Keywords
    Ge-Si alloys; boron; heterojunction bipolar transistors; semiconductor device models; semiconductor doping; SiGe base; SiGe:B; accelerating field effects; base bandgap grading; base transit time; base transit time expressions; doping grading; graded B profile; heterojunction bipolar transistors; opposing drift field; retarding field;
  • fLanguage
    English
  • Journal_Title
    Electronics Letters
  • Publisher
    iet
  • ISSN
    0013-5194
  • Type

    jour

  • DOI
    10.1049/el:19910884
  • Filename
    81272