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Aluminum nitride (AlN) films were grown on silicon (Si) substrates by chemical vapor deposition (CVD). The films were characterized by scanning electron microscopy (SEM) and x-ray diffraction (XRD). The refractive index of the AlN films was determined by ellipsometry. Current-voltage and current-temperature characteristics were performed on metal-AlN-p+ Si structures with Pt, Au and Al as metal electrodes. The characteristics showed that at high field and high temperature the carrier conduction mechanism in the film was dominated by Frenkel-Poole emission. The relative dielectric constant of the AlN films was estimated to be 9.66+0.3 from capacitance-voltage-frequency (C-V-f) measurements on Au-AlN-p+ Si.

We are reporting the first quantitative photoresponse characteristics of boron doped hot-filament CVD (HFCVD) diamond based Schottky diodes using semi-transparent aluminum contacts in the spectral range of 300–1050 nm. Quantum efficiencies, obtained without correction for surface reflection in the visible and near UV region, were between 5 % and 10% when the diodes were unbiased. Effect of reverse bias on the photoresponse was investigated at selected photon energies. Reverse biased diodes exhibit increasing photoresponse and ultimately saturation. Quantum efficiency as high as 30% was also obtained at 500 nm, when a reverse bias of over I volt was applied. The photoresponse mechanism of CVD diamond Schottky diodes is also discussed. A Schottky barrier height of 1.15 ± 0.02 eV for Al-HFCVD diamond contacts was determined using the d.c. photoelectric method.

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Aluminum nitride (A1N) films were grown by chemical vapor deposition (CVD) on boron doped diamond films deposited by the hot-filament CVD (HFCVD) method. The films were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD) and Raman spectroscopy. The electrical characterization of the A1N/diamond interface was performed by current-voltage (I-V) and capacitancevoltage (C-V) measurements. The resulting films showed one x-ray diffraction peak of (100) oriented A1N and three diamond diffraction peaks of (1 1 1), (220) and (33 1) orientation. The Raman spectra showed two peaks, one at 660 cm' due to scattering by the A1N lattice and the other at 1335 cm' by the diamond lattice. The I-V measurements on the metal(W)/diamond/Si/Al structure showed ohmic behavior from which the diamond film resistivity of 5 x 1O a-cm was estimated. The I-V measurements on the W/A1N/diamond/Si/Al structure showed rectifying behavior. The capacitance of the film was independent of the applied voltage and was dominated by the diamond bulk capacitance.