Title :
Performance enhancement of double-emitter HPTs with different emitter-area ratios
Author :
Tan, S.W. ; Chen, H.R. ; Lin, A.H. ; Chen, W.T. ; Lour, W.S.
Author_Institution :
Dept. of Electr. Eng., Nat. Taiwan-Ocean Univ., Keelung, Taiwan
fDate :
5/13/2004 12:00:00 AM
Abstract :
Single- and double-emitter heterojunction phototransistors (HPTs) with the same total emitter area have been fabricated and qualitatively investigated. The double emitters in two kinds of DE-HPTs are designed to have area ratio of 1:1 and 1:2, respectively. Both a positive and a negative voltage applied to the second emitter can control and enhance the collector photocurrent. It is found that 1:2 and 1:1 DE-HPTs exhibit 1.85- and 1.5-fold optical gain of that from an SE-HPT, respectively.
Keywords :
heterojunction bipolar transistors; phototransistors; collector photocurrent; double emitter heterojunction phototransistors; emitter area ratios; optical gain; single emitter heterojunction phototransistors;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:20040383
