Ballistic electron emission microscopy to probe interfaces of simple device structures

Abstract Ballistic electron emission microscopy (BEEM) is a powerful new technique capable of probing the electrical barriers at semiconductor interfaces on a microscopic scale. It is also very useful for probing the details of the semiconductor band structures, particularly the positions of the upper valleys in the conduction band. Over the past two years we have used BEEM to investigate both metal-semiconductor contacts and heterojunction interfaces, and we report here some of the data obtained during the investigation. The Au GaAs and Au/InGaAs/AlGaAs systems have been chosen as a vehicle to demonstrate both the power of the technique and its limitations.