Modulation Spectroscopy Characterization of Semiconductor Heterostructures

This paper reviews the use of modulation spectroscopy for the characterization of a wide variety of semiconductor heterostructures and devices. Some systems that will be discussed include pseudomorphic GaAlAs/InGaAs/GaAs modulation-doped quantum well high electron mobility transistors (including the 300K determination of the two-dimensional electron gas density), GaAlAs/GaAs, InP/InGaAs, InGaP/GaAs, InAlAs/InGa As and InGaAs/GaAs heterojunction bipolar transistors (including the determination of the built-in fields/doping levels in the emitter and collector regions), GaAs/GaAlAs quantum well infrared detectors, quantum well lasers and GaAs/GaAlAs quantum dots. Particular attention will be paid to non-destructive, contactless techniques such as photoreflectance, contactless electroreflectance and differential reflectometry that can be performed on entire wafers.