The InP/GaAsSb type-H heterostructure system and its application to high-speed DHBTs and photodetectors: physics, surprises, and opportunities (INVITED)

Abstract

The InP/GaAsSb/InP "type-II" heterostructure system is of interest for high-speed devices such as photodetectors and double heterostructure bipolar transistors (DHBTs) because its band alignment enables the straightforward injection of electrons from a ~0.72 eV p-type GaAsSb layer into n-type InP without any need for interface grading. We briefly review the salient features of the InP-GaAsSb system, and consider some of the surprising device characteristics encountered in InP/GaAsSb -based devices. In several respects, the InP/GaAsSb system is shown to offer very appealing opportunities for the development of high-speed NpN DHBTs with ultrathin base and collector layers.

Fabrication and Characterization of Self-Aligned InAlAs/InGaAsSb/InGaAs Double Heterojunction Bipolar Transistors

“…As shown in Figure 10 (a), the DHBT with an effective emitter area of 0.65 × 8.65 µm 2 showed f T and f max of 260 and 485 GHz, respectively, at a collector current density of 302 kA/cm 2 . Figure 10 (b) compares the f T and f max of our InGaAsSb DHBTs with those taken from literatures [1][2][3][4][5][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. The DHBT with 0.65 × 8.65 µm 2 emitter area has delivered a comparable performance among InP-base HBTs.…”