The electronic properties of Cu-phthalocyanine (CuPc) molecules flat lying along the channels of the Au(110) reconstructed surface have been investigated by means of ultraviolet and x-ray photoelectron spectroscopy. The ordered chains give rise to a highly ordered single-layer structure with a (5x3) symmetry. Although from the core-level analysis not any significant charge transfer between the molecules and the underlying Au surface is observed, the valence band photoemission data bring to light CuPc-induced features localized at the interface. In particular, energy versus momentum dispersion of an interface state reveals a bandwidth of about 90 meV along the enlarged Au channels, where the CuPc chains are formed, with a defined fivefold symmetry well fitting the CuPc intermolecular distance.

A copper-phthalocyanine (CuPc) thin film and a highly ordered CuPc single layer prepared on the Au(110) surface are electron doped by exposition to alkali metal. The CuPc thin film remains insulating when the donated electrons flow into the unoccupied molecular orbitals. The CuPc/Au interface is metallic in the absence of doping, and transition to an insulating state is observed by the filling up of the former empty states. In particular, two occupied states are generated by filling the lowest unoccupied molecular orbitals with the doping electrons. Sweeping of the former empty states through the Fermi energy does not induce any enhancing of the electronic spectral density, as detected by high-resolution photoelectron spectroscopy. Electron correlation and Jahn-Teller effects act to determine the insulating response of electron-doped CuPc

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We present a method of producing a long-range ordered pentacene ultra-thin film on a benzenethiol organic buffer layer at saturation coverage, deposited on a cleaned. single crystalline Cu(100) surface, by means of ultra-high-vacuum organic molecular beam epitaxy. The growth morphology is investigated using in-situ low-energy electron-diffraction (LEED) and high-resolution UV photoelectron spectroscopy (HR-UPS). The change in Surface symmetry from c(4x4) at low coverage to c(2 x 6)/c(2 x 2) at saturation coverage of benzenethiol has been examined by LEED. The corresponding valence band modifications have been found by HR-UPS. Pentacene layers Lip to a thickness of 0.6nni possess exactly the same symmetry of the beneath organic buffer layer at saturation coverage, but with more intense and sharper spots as observed in the LEED patterns

Radio Frequency Micro-Electro-Mechanical System (RF-MEMS) represents a feasible solution to obtain very low power dissipation and insertion loss, very high isolation and linearity switch with respect to “solid state” technologies. In this paper, we demonstrate the full integration of RF-MEMS switches in the GaN-HEMT (Gallium Nitride/High Electron Mobility Transistor) fabrication line to develop RF-MEMS devices and LNA-MMIC (Low Noise Amplifier/Monolithic Microwave Integrated Circuit) prototype simultaneously in the same GaN wafer. In particular, two different coplanar wave (CPW) LNAs and a series of discrete RF-MEMS in ohmic-series and capacitive-shunt configuration have been fabricated. RF-MEMS performances reveal an insertion loss and isolation better than 1 and 15 dB, respectively, in the frequency range 20–50 GHz in the case of pure capacitive shunt switches and in the frequency range 5–35 GHz for the ohmic-series switches. Moreover, the GaN HEMT device shows an Fmax of about 38 GHz and a power density of 6.5 W/mm, while for the best LNA-MMIC we have obtained gain better than 12 dB at 6–10 GHz with a noise figure of circa 4 dB, demonstrating the integration achievability.