GaAs/Ge/GaAs heterostructures by molecular beam epitaxy

S. Strite, M. Selim Ünlü, K. Adomi, Guangjun Gao, Anil Agarwal, Angus Rockett, H. Morkoç̌, D. Li, Yuki Nakamura, Nobuyuki Otsuka

Journal of Vacuum Science & Technology B Microelectronics Processing and Phenomena · 1990 · 52 citations · 0 references

Concepts

Abstract

We report high quality GaAs/Ge/GaAs heterojunctions grown by molecular-beam epitaxy. Antiphase domain (APD) free GaAs on Ge growth, as verified by high-energy electron diffraction and transmission electron microscopy, has been achieved for epitaxial (100) Ge surfaces misoriented towards [011] while APDs are observed to annihilate after roughly 500 Å of GaAs growth on nominally (100) epitaxial Ge. The outdiffusion of Ga and As into epitaxial Ge and outdiffusion of Ge into epitaxial GaAs was investigated by in situ x-ray photoemission spectroscopy and secondary ion mass spectroscopy. The electrical properties of the heterojunctions are studied and the transistor characteristics of a prototype N–Al0.22Ga0.78As/p+-Ge/n-GaAs heterojunction bipolar transistor is presented.