抄録
By using an energy transport model, we simulate cutoff frequency fT- versus collector current density Ic characteristics of npn-n AlGaAs/GaAs heterojunction bipolar transistors (HBTs) with various n--collector thickness and n--doping densities. It is found that the calculated fr characteristics show double peak behavior when the n--layer is thick enough and the n--doping is high enough to allow existence of neutral n--region. The mechanism of the double peak behavior is discussed by studying energy band diagrams, electron-energy profiles and electron-velocity profiles. Particularly, we discuss the origin of the second peak (at higher Ic) which is not usually reported experimentally.
本文言語 | English |
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ページ(範囲) | 437-442 |
ページ数 | 6 |
ジャーナル | VLSI Design |
巻 | 8 |
号 | 1-4 |
DOI | |
出版ステータス | Published - 1998 |
外部発表 | はい |
ASJC Scopus subject areas
- ハードウェアとアーキテクチャ
- コンピュータ グラフィックスおよびコンピュータ支援設計
- 電子工学および電気工学