Improved emitter transit time using AlGaAs-GaInP composite emitter in GaInP/GaAs heterojunction bipolar transistors

Abstract

A new emitter structure based on composite graded AlGaAs-GaInP approach is described, which allows significant reduction of BE and improved high-frequency performance. A theoretical study of the composite and conventional emitter HBTs is performed to prove the superiority of composite emitter HBTs using Monte Carlo simulation of their transport properties. The self-aligned HBTs fabricated in this study are grown by CBE with TBA/TBP precursors. The current gain cutoff frequency (T) was 62 GHz for the composite emitter design HBT, and 45 GHz for conventional emitter design HBT. The BE achieved with the composite emitter designs was by at least 3 times lower than that of conventional designs and does not show significant variation with collector current. This leads to enhanced T characteristics by 15% for composite emitter HBT designs and confirms the theoretical expectations.

First principle investigation of stuctural, electronic, and thermoelectric properties of Ga1-x In x P (x = 0.0 to 1.0) alloys

“…Also, Ga 0.5 In 0.5 P is used as a vertical cavity surface emitting laser [18] which is almost lattice-matched to GaAs. These alloys are potential candidates for sensor application because of the extremely sensitive nature to external influences including external fields, temperature, strain and pressure [19].…”

Physics-based model for tunnel heterostructure bipolar transistors

“…These devices are very useful for high power microwave applications. Recently, improved I-V characteristics of these devices have been achieved by using δ doping layers [2] and composite layers in the emitter [3] and collector regions [4,5].…”