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A study including core level photoelectron spectroscopy and photoelectron diffraction was performed in order to obtain information on the high-temperature arsenic adsorption on the InP(110) surface. Surface bonding, surface structure and interface reactions were investigated in comparison to InP(110). An arsenic–phosphorus exchange reaction replacing the first layer phosphorus atoms by arsenic and forming a monolayer of InAs was observed using photoelectron spectroscopy. A polar angle scanned photoelectron diffraction study was performed in order to obtain structural information on this arsenic-exchanged surface. Comparison of simulations with experimental angle distribution curves applying double scattering calculations supports a bond angle rotation of this surface with a tilt angle of ω=29°.

(Soft) x-ray photoelectron spectroscopy and x-ray photoelectron diffraction (XPD) were used to investigate interface reaction, film morphology and surface order at both the Pb/InP(110) interface and the corresponding interface including an arsenic interlayer. The core level spectra did only reveal very weak interface reaction, which could be suppressed by arsenic. Growth of three dimensional islands of metallic lead was observed on the Pb/InP(110) interface. Lead deposition onto an ordered arsenic monolayer on InP(110) was accompanied by segregation of approximately half the arsenic. The growth mode of the lead film changed dramatically from three-dimensional island growth to a layer-by-layer-like mode due to the surfactant arsenic. XPD patterns provided evidence of ordered lead growth on the original system while the arsenic induced smooth Pb films show strong disorder.

In relation to investigations of the surface composition of ordered alloys in the region of their critical temperature, the elemental concentrations of the top two atomic layers of a Au 3 Cu (001) alloy surface were determined with low energy ion scattering in the temperature range of 300–925 K. Up to 550 K the first layer consists only of Au atoms and the second layer of Cu atoms. Above this temperature desegregration occurs; from the temperature dependence a segregation enthalpy of 47 kJ/mole could be deduced. The segregation results in a contraction of the top layer distances compared to the bulk values. The segregation kinetics can be described as an exchange process between the top atomic layers with an activation energy of 0.2–0.3 eV. The temperature dependence of the surface concentration of this alloy is determined by the segregation process rather than by the bulk ordering phase transition.

The effect of an intermediate arsenic monolayer on the evolution of an Ag InP (110) interface has been studied using high resolution photoemission. The interface reaction is suppressed by the intermediate layer very effectively. Part of the As layer segregates on top of the growing Ag film and acts as a surfactant during the initial stages of the growth. The growth mode during the initial stages of the silver film formation is changed from island to Stranski—Krastanov-like growth. There is an increase of the Schottky barrier by 0.1 eV due to the As interlayer. Experimental results of Schottky barrier heights are discussed in terms of both reaction-induced defect formation and theoretical predictions regarding dangling bond saturation.

Direct measurements of circuit node signals without changing the performance of the circuitry are essential in modern FA but often impossible for recent IC technologies. This paper shows new methods, based on FIB backside circuit edit, allowing access to every existing circuit node at the device level, and discusses options for probing and discrete characterization.

Scanning spreading resistance microscopy (SSRM) was performed in surrounding-gate transistors for 70 nm dynamic random access memories. Sub-10 nm features were resolved using full diamond tips and different processing schemes were correlated with the electrical characteristics of the devices and the SSRM measurements. SSRM was found to be a powerful tool for the characterization and failure analysis determination of this device concept in the very small scale.

The formation of the Ge/InP(110) interface at room temperature and the influence of an additional arsenic interlayer on the interface chemistry, the film growth, and the electronic properties of this heterostructure have been investigated using core and valence level photoemission and low-energy electron diffraction. We have shown that an As interlayer at the Ge/InP(110) interface can completely suppress the interface reaction of the Ge with the substrate at room temperature, including partial In–Ge exchange and In segregation. The electronic situation at the interface is characterized by an anomalous evolution of the surface Fermi level with Ge coverage on InP(110) and a high valence band offset of ΔEv=1.01±0.07 eV, which is reduced to ΔEv=0.78±0.07 eV for Ge/As/InP(110). We may attribute the differences of the measured valence band offsets to a reaction-induced interface doping of the InP at the real Ge/InP(110) interface, which introduces an interface dipole layer. A calculation of this interface dipol...