Title :
Forward transit delay in In0.53Ga0.47As heterojunction bipolar transistors with nonequilibrium electron transport
Author :
Laskar, J. ; Nottenburg, R.N. ; Levi, A.F.J.
Author_Institution :
Dept. of Electr. Eng., Hawaii Univ., Honolulu, HI
fDate :
11/1/1993 12:00:00 AM
Abstract :
Summary form only given. The authors have performed a comprehensive study of the high-frequency current gain h21 in InP-In0.53Ga0.47As HBTs (heterojunction bipolar transistors) (with an emitter area AE=3.5 μm×3.5μm and 500 Å base thickness with p-type doping level of 1×1020 cm-3) over the temperature range 55 K⩽T⩽340 K. Detailed device modeling was used to extract τF from the measured data. Results show that the intrinsic emitter-collector forward delay decreases from a value of τF=0.5 ps at a temperature T=340 K and saturates at a value of τF~0.28 ps for T=150 K and below. This marked decrease in measured forward delay with decreasing temperature arises from the temperature dependence of electron scattering in the device. The extrinsic current gain cutoff frequency, fT, of these devices at T=55 K is greater than 300 GHz. Such a high value of fT can only be explained by the existence of extreme nonequilibrium electron transport in the base and collector
Keywords :
III-V semiconductors; delays; gallium arsenide; heterojunction bipolar transistors; indium compounds; solid-state microwave devices; 300 GHz; 55 to 340 K; InP-In0.53Ga0.47As; current gain cutoff frequency; device modeling; electron scattering; forward transit delay; heterojunction bipolar transistors; high-frequency current gain; intrinsic emitter-collector forward delay; nonequilibrium electron transport; p-type doping level; temperature dependence; Data mining; Delay; Doping; Electrons; Heterojunction bipolar transistors; Performance evaluation; Performance gain; Semiconductor process modeling; Temperature dependence; Temperature distribution;
Journal_Title :
Electron Devices, IEEE Transactions on
