Study of semiconductor surfaces and interfaces using electromodulation

摘要: The modulation spectroscopy technique of electromodulation (EM) is a major tool for the study and characterization number semiconductor surfaces/interfaces also evaluation process-induced damage at surfaces. most useful forms EM are photoreflectance (PR) contactless electroreflectance (CER) because they sensitive to surface/interface electric fields often yield sharpest structure (third-derivative lineshape unmodulated spectrum in case bulk/thin-film material). For sufficiently high PR/CER spectra may exhibit Franz–Keldysh oscillations, which direct measure relevant field. Furthermore, PR CER require no special mounting sample hence can be employed situ or non-destructively on wafer-sized material. This article will discuss some recent applications investigation surfaces/interfaces, such as: effects surface Si; Fermi-level pinning III–V materials, including low-temperature-grown GaAs (with excess As) wurtzite GaN; Schottky barrier formation; (sputtering, reactive ion etching, chemically assisted beam etching) materials; homojunctions (GaAs/GaAs); heterojunctions (GaAlAs/GaAs, ZnSe/GaAs, CdTe/GaAs, AlInAs/InP, InGaAs/InP, InGaAs/InAlAs InGaN/GaN); device structures as heterojunction bipolar transistors pseudomorphic high-electron-mobility transistors. A these studies have been performed with an ultrahigh vacuum environment. Copyright © 2001 John Wiley & Sons, Ltd.