The use of mixed alloy contacts to engineer the interfaces and electrical characteristics of metal-InP contacts

Abstract

The present study has examined the relationship between the I-V electrical characteristics and the interfacial microstructure present in Ag/In-(100)InP metal-semiconductor contacts. By depositing mixed alloy contacts of silver and indium on to (100)InP surfaces and then using thermal treatments to activate the interface, a variety of different microstructures has been generated within the interface of the contact. The different microstructures have then been related to the electrical characteristics of the contact. It has proved possible to engineer the contact's interface into differing states that reproducibly generate Schottky or truly Ohmic-like behaviour. The alloy contacts have been deposited with precise compositions by making use of separate Knudsden sources operating within an MBE system. The contact's interface has been characterised with Auger profiling and by direct observation with scanning electron microscopy.