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Auger Electron Spectroscopy (AES) in conjunction with argon ion sputtering and Secondary Ion Mass Spectrometry (SIMS) have been used for investigations of homogeneity and interface effects in epitaxial GaP films grown by Molecular Beam Epitaxy (MBE) on GaAs substrates. Large differences in the abruptness of the interface are observed as a function of growth temperature, and there is excellent agreement between the two techniques.

Auger electron spectroscopy in conjunction with simultaneous Argon‐ion sputtering have been used in a study of the chemical depth profiles of the near‐interface regions in MOS and MNOS device structures. Our experimental results show that all of these interfaces are nonabrupt and phase separated. The Al–SiO2 interface has inclusions of Si and A12O3; the SiO2–Si interface appears to be a mixed phase of Si and SiO2 over several nanometers and the nitride–oxide interface is an oxynitride. The width of these interfaces varies from 35 to several hundred angstrom, depending on the deposition technique and on the deposition conditions. The inherent limitations in the depth resolution of Auger/sputter profiling are discussed in some detail. We also describe the precautions we have taken to minimize electron and ion beam induced distortion of the Auger spectra and the depth profiles.

The crater edge formed in Si‐SiO2 films by appropriate ion‐beam etching provides an angle‐lapped surface analogous to that produced by usual mechanical means; however, the angle can be usefully reduced by 3 orders of magnitude, allowing much greater spatial resolution. Furthermore, in contrast to conventional depth profiling, the separation of the etching and analysis permits repetitive measurements to be made conveniently; a fact of considerable utility in interface analysis.

Specific ions in solution can be determined potentiometrically with ion-selective electrodes. With conventional electrodes the high electrical resistivity of the solid membranes necessitates the use of high-impedance voltmeters and shielded cables. Here we report on a new ion-selective electrode where amplifier electronics has been integrated in the sensor head, whereby the membrane response is transformed into a low-impedance output signal. The MOSFET input stage of the amplifier provides an input resistance of up to 1012 ohm, allowing the use of solid inner contacts on the membranes in most cases. With this electrode the requirements for the registration equipment and for the signal transmission lines and size are relaxed considerably, providing advantages in terms of low cost, miniaturization, computer compatibility and remote sensing ability.