Title :
Investigation of current transport and charges in graded base HBTs
Author :
Ryum, Byung R. ; Abdel-motaleb, Ibrahim M.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Northwestern Univ., Evanston, IL, USA
Abstract :
An all injection model for graded-base HBTs (heterojunction bipolar transistors) has been developed and found to agree well with experimental results. The model shows that assuming low injection level and base transit time current independence may not be valid in all cases. Recombination current components have been formulated. The base grading effect on current components and current gain is investigated. The results show that as Al mole fraction increases gain increases to a maximum, then decreases
Keywords :
heterojunction bipolar transistors; semiconductor device models; base transit time current independence; current transport; graded base HBTs; heterojunction bipolar transistors; injection model; recombination current components; Analytical models; Charge carrier processes; Circuits; Current density; Electron emission; Electron mobility; Heterojunction bipolar transistors; Niobium; Photonic band gap; Temperature;
Conference_Titel :
Bipolar Circuits and Technology Meeting, 1990., Proceedings of the 1990
Conference_Location :
Minneapolis, MN
DOI :
10.1109/BIPOL.1990.171162
