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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.

The Si oxidation rate at high temperatures is increased by heavy P doping. Sputter ion‐Auger techniques have been used to investigate the oxide thickness and P concentration after 900 °C oxidation with an initial P surface concentration of between 2×1018 and 3.2×1020/cm3. Phosphorus was found to pile up in the Si‐SiO2 interface region. The maximum P concentration near the interface was found to depend on doping and was (at certain P concentrations) an order of magnitude larger than that predicted by redistribution theory. A vacancy–P‐complex model is presented to explain the observed behavior. A correlation between the selective pile‐up of P at the interface and the current gain of planar bipolar transistors is reported.

Auger electron spectroscopy has been used in conjunction with argon ion sputtering in a study of the chemical structure of the interface region between thermally grown SiO2 and the Si substrate. The distorting effects of the electron and ion beams are dealt with in detail, and we show how the beam parameters can be chosen to minimize instrumental artifacts in the Auger spectra and the chemical depth profiles of the SiO2‐Si interface. We discuss the SiO2‐Si interface in terms of a morphology model which includes a natural interface roughness and inclusions of silicon in the oxide close to the interface. The width of the interface of a 1000‐A oxide grown at 1200 °C in dry O2 on Si (100) is approximately 35 A.

The amorphous-crystalline structure transition in vacuum deposited germanium films is investigated in terms of change in electrical conductivity. The transition is observed to occur at TD = 235 °C, and it appears as an abrupt change in conductivity of four orders of magnitude. The comparatively large scattering among published transition temperatures is discussed with respect to methods of temperature measurement. Der Ubergang zwischen der amorphen und kristallinen Struktur von im Vakuum aufgedampften Germaniumschichten wird mittels Veranderungen in der elektrischen Leitfahigkeit untersucht. Der Ubergang wird bei TD = 235 °C beobachtet, und er erscheint als eine steile Veranderung in der Leitfahigkeit um vier Grosenordnungen. Die verhaltnismasig grose Streuung der veruffentlichten Ubergangstemperaturen wird unter Berucksichtigung der Methoden fur Temperaturmessungen diskutiert.

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.

Transverse magnetoresistance in p-type germanium substrates, supporting germanium films, is investigated. The experimental results support a magnetoresistance theory which includes optical phonon scattering. The electrical properties of the substrates appear to be unaffected by the deposited layers. Die transversale Magnetowiderstandsanderung in Germaniumsubstraten, die Germanium-schichten tragen, wird untersucht. Die experimentellen Resultate unterstutzen eine Magnetowiderstandstheorie, die die Streuung optischer Phononen einbezieht. Die elektrischen Eigenschaften der Substrate scheinen nicht von den aufgedampften Schichten beeinflust zu werden.

The elastoresistance coefficients of germanium films are investigated with particular attention to their dependence on the deposition temperature TD. The structure sensitivity of the resistivity and elastoresistance coefficients reveals a transition from an amorphous to a polycrystalline structure at TD = 235°C for films on mica or polyimide substrates. For slightly higher temperatures preferential orientation takes place, while the films exhibit random crystallite orientation at still higher deposition temperatures. Nonlinear elastoresistance effects are observed in polycrystalline germanium films. Die Elastowiderstandkoeffizienten von Germaniumschichten werden mit besonderer Berucksichtigung ihrer Abhangigkeit von der Substrattemperatur TD untersucht. Die Strukturempfindlichkeit der Widerstands- und Elastowiderstandskoeffizienten zeigt einen Ubergang von amorpher zu polykristalliner Struktur bei TD = 235°C fur Schichten auf Substraten von Glimmer oder Polyimide. Fur etwas hohere Temperaturen beobachtet man eine bevorzugte Orientierung, wahrend fur noch hohere Temperaturen die Schichten statistisch verteilte Kristallit-Orientierungen aufweisen. Nichtlineare Elastowiderstandseffekte werden in polykristallinen Germaniumschichten beobachtet.

The theory of Hall and transverse magnetoresistance effects for mixed scattering and warped energy bands in p-type germanium has been extended to include optical phonon scattering. The extended theory agrees well with the experimental Hall factor as function of temperature. Galvanomagnetic phenomena observed in germanium films are discussed with reference to the extended theory. Deduced values of carrier density and mobility show that defect acceptors such as dislocations largely determine the electrical properties of germanium films. A method is described by which the Hall factor may be arrived at through independently measured transverse magnetoresistance. Die Theorie des Halleffekts und des transversalen Magnetowiderstandseffekts fur gemischte Streuung und gebogene Energiebander in p-leitendem Germanium wird weitergefuhrt und schliest optische Phononen ein. Die weitergefuhrte Theorie stimmt mit dem experimentellen Hall-Faktor als Funktion der Temperatur sehr gut uberein. Die in Germaniumschichten beobachteten, galvanomagnetischen Phanomene werden in Bezug auf die weitergefuhrte Theorie diskutiert. Abgeleitete Werte der Dichte und der Beweglichkeit der Locher zeigen, das Defekt-Akzeptoren wie Versetzungen die elektrischen Eigenschaften der Germaniumschichten wesentlich bestimmen. Eine Methode zur Bestimmung des Hall-Faktors durch eine unabhangige Messung des transversalen Magnetowiderstandseffekts wird beschrieben.

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.

Chemical effects on Auger spectra have been studied for some time. Only recently, however, has it been shown that these effects can be used to study the ’’chemical structure’’ of interfaces by observing the rate of appearance of one chemical state and the rate of disappearance of another chemical state of an element during depth profiling.1–3 In this way, the simultaneous existence of different states of the same element can be observed. Percentages of the atoms in these different chemical states present at any position in the interface can be determined. Also, the chemical state of various elements present can be identified and changes mapped out through interfaces.Studies of the chemical structure of interfaces offer important information in the attempt to understand the behavior of interfaces in semiconductor devices. The characterization of these interfaces in Si and Al is of critical importance to LSI technology, particularly for MOS devices. The system which is of greatest interest in actual device ...