Sub-f(t) gain resonance of InP/InGaAs-HBTs
2002 (English)In: IEEE Transactions on Electron Devices, ISSN 0018-9383, Vol. 49, no 2, 213-220 p.Article in journal (Refereed) Published
Advanced npn-InP/InGaAs HBTs are often operated at high current levels for optimum high-speed performance. Because of velocity modulation effects, these transistors may operate in base-pushout although measurements of the cut-off frequency f(t) indicate the opposite. We show that the low mobility of the holes has a strong effect on the transistor operation in this regime, which is only revealed from a dynamic analysis: The unilateral power gain peaks far below f(t) followed by a -40 dB/dec roll-off. The effect was thoroughly analyzed and as a result, we present a simple equivalent circuit model that successfully describes transistors operating in pushout up to very high frequencies.
Place, publisher, year, edition, pages
2002. Vol. 49, no 2, 213-220 p.
base-pushout, high-frequency limitations, hole velocity, InP-HBT, Kirk-effect, unilateral power gain, bipolar-transistors, currents
IdentifiersURN: urn:nbn:se:kth:diva-21290ISI: 000173613700001OAI: oai:DiVA.org:kth-21290DiVA: diva2:339988
QC 201005252010-08-102010-08-10Bibliographically approved