Unintentional impurity incorporation at the interface between InP substrate and buffer layer grown by LP-MOVPE

Abstract

Multilayer structures for many device applications require a highly resistive and perfect crystalline InP buffer layer. Due to unintentional impurity incorporation at the substrate epitaxial layer interface, this buffer layer is often conductive leading for example to poor pinch off characteristics in diodes. In this study we report on a systematic investigation of the origin of highly conductive epitaxial InP buffer layers and how they can be avoided.