In situ real time Auger analyses during oxides and alloy growth using a new spectrometer design

Abstract

A new Auger electron spectrometer probe designed to monitor the surface composition during growth is presented. The device is able to operate without impairing the deposition process and is compatible with the environmental constraints of deposition chambers. Auger electron excitation can be generated by the electron beam used for reflection high energy electron diffraction studies, thus allowing simultaneous elemental and structural sample analyses. The Auger probe is mounted using one of the ports facing the sample, preferably at normal incidence angle. The distance between the sample surface and analyzer is large enough to clear the fluxes of material from multiple deposition sources commonly used in growth chambers. The probe has a variable energy resolution that can be electronically adjusted and can be set for higher sensitivity and shorter acquisition time or for better energy resolution. Examples of applications are shown to illustrate the capabilities of the instrument. In one example, the growth of zinc oxide (ZnO) layers is monitored during the deposition and in the other example, the stoichiometry of the lanthanide alloys (dysprosium and terbium) is deduced from the variation of the Auger MNN lines for pure elements and alloyed layers. In addition to AES, the probe provides reflection electron energy loss spectroscopy spectra of the distribution of characteristic energy losses.