Active solid-state devices (e.g. – transistors – solid-state diode – Heterojunction device – Bipolar transistor
Patent
1995-06-05
1996-06-04
Fahmy, Wael M.
Active solid-state devices (e.g., transistors, solid-state diode
Heterojunction device
Bipolar transistor
257198, H01L 310328, H01L 310336
Patent
active
055235948
ABSTRACT:
An AlGaAs/GaAs heterojunction bipolar transistor in which a base doping concentration is set to be as very high as 5.times.10.sup.19 cm.sup.-3 or more to cause a band gap narrowing effect and to reduce a band gap difference by an amount corresponding to the band gap narrowing effect, an Al composition ratio, i.e., x in an Al.sub.x Ga.sub.1-x As material of an emitter layer is set to be less than 0.25, whereby an emitter resistance can be made small, an operating speed can be made fast and a current gain can be made high. Preferably, the base doping concentration is set to be 1.2.times.10.sup.20 cm.sup.-3 or more so that the operation speed can be made remarkably fast.
REFERENCES:
patent: 4739379 (1988-04-01), Akagi et al.
patent: 4794440 (1988-12-01), Capasso et al.
patent: 4929997 (1990-05-01), Honjo et al.
patent: 4933732 (1990-06-01), Katoh et al.
patent: 4958208 (1990-09-01), Tanaka
patent: 4967254 (1990-10-01), Shimura
patent: 4979009 (1990-12-01), Kusano et al.
patent: 5124270 (1992-06-01), Morizuka
H. C. Casey, Jr. et al., "Concentration-dependent absorption and spontaneous emission of heavily doped GaAs", Journal of Applied Physics, vol. 47, No. 2, Feb. 1976, pp. 631-643.
H. Kroemer, "Heterostructure Bipolar Transistors and Integrated Circuits", Proceedings of the IEEE, vol. 70, No. 1, Jan. 1982, pp. 13-25.
P. Bhattacharya, "The relationship of the D-X center in Al.sub.x Ga.sub.1-x As and other III-V alloys with the conduction band structure", Semicond. Sci. Technol. 3, 1988, pp. 1145-1156.
N. H. Sheng et al., "High Power GaAlAs/GaAs HBT's for Microwave Applications", The Proceedings of the IEDM, 1987, pp. 619-622.
Hayes et al; "Hot electron transport in a graded band-gap base HBT"; Aug. 8, 1988; pp. 490-492; Applied physics letters. 53.
Fahmy Wael M.
Kabushiki Kaisha Toshiba
LandOfFree
Heterojunction bipolar transistor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Heterojunction bipolar transistor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heterojunction bipolar transistor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-385752