Measurement of heterojunction band offsets by admittance spectroscopy: InP/Ga0.47In0.53As

Abstract

We discuss the use of admittance spectroscopy to measure the band offsets of semiconductor heterojunctions. By using this method to analyze the dynamic response of p-n junctions containing lattice-matched InP/Ga0.47In0.53As superlattices we can independently determine both the conduction- and valence-band offsets for this materials system. We find that the sum of these offsets equals the known band-gap difference between InP and Ga0.47In0.53As and that the ratio of the conduction-band offset to the valence-band offset is 42:58.