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The evolution of surface morphology, crystallinity, and growth modes of c‐axis‐oriented superconducting YBa2Cu3O7−x (YBCO) thin films deposited by pulsed laser deposition on SrTiO3(100) and NdGaO3(110) substrates have been systematically investigated with scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), x‐ray energy‐dispersive spectroscopy, and x‐ray diffraction. SEM and AFM images of the YBCO films grown on NdGaO3 with a sequential thickness revealed that the films were rather smooth and grew in a two‐dimensional manner. In contrast, the YBCO films of the same thickness on SrTiO3 were found to have spiral growth features, even in the thinnest film (10 nm or 8 unit cells thick) indicating that an island growth mechanism took place. A change of the full width at half‐maximum of the rocking curves of the (005) reflection with the film thickness showed that the crystallinity of the films on NdGaO3 was much better than those grown on SrTiO3, suggesting that a lattice match is a crucial factor to obtain good crystallinity. In the early stages of growth the preferential a‐axis orientation of the films on NdGaO3, as revealed by TEM, was consistent with the smooth and featureless film surfaces found, in contrast to the c‐axis growth mode on SrTiO3.

Thin diamond films have been grown by hot filament chemical vapor deposition (CVD) on untreated, diamond powder scratched and d.c.-bias pretreated Si(111), SiO2 and graphite substrates. The deposits were characterized using X-ray photoelectron spectroscopy, scanning Auger microprobe and scanning electron microscopy. The increased surface oxide thickness due to scratching has no influence on the nucleation of diamond films since SiO2 films of known thickness have been found to be reduced under growth conditions. Positive d.c.-bias pretreatment leads to an increased number density of nuclei which can be further increased by permanent biasing throughout the deposition. The pretreatment causes intermediate deposition of turbostratic carbon which promotes nucleation of diamond. The increased number density of nuclei is discussed in relation to deposition of diamond on various forms of graphite.

Application of single-crystal diamond wafers or polycrystalline diamond films as substrates for high T c superconducting films may open new avenues for the development of broadband optical sensors such as bolometers and optically triggered fast switches, as well as for high-density packaging, owing to their low heat capacity and excellent thermal conductivity. Superconducting YBa 2 Cu 3 O 7− x (YBCO) thin films were deposited on polycrystalline diamond films and single-crystal diamond (110) substrates using a pulsed-laser deposition technique. Auger electron spectroscopy depth profiles of YBCO films grown directly on the diamond films and diamond substMtes showed that carbon diffused into the YBCO films. Therefore, to prevent carbon diffusion, a composite buffer layer of YSZ/Si 3 N 4 (YSZ: yttria-stabilized zirconia, 8% Y 2 O 3 ) was used. Both resistance and magnetization measurements of the YBCO films with the composite buffer layer showed that a superconducting phase with a T c o (onset T c ) of 85–90 K was formed. However, the T c values ( R = 0) of the same films obtained from resistance measurements were in the range of 43–50 K. Scanning electron microscopy and Atomic force microscopy investigations showed granular morphology and formation of cracks in the films.

Turbostratic carbon (TC) films pre-deposited onto copper substrates cause extremely rapid nucleation of diamond when heated in the presence of atomic hydrogen at approximately 1273 K. Transmission electron microscopy and diffraction, Auger electron spectroscopy, and atomic force microscopy were used to characterize the catalytically synthesized TC films. Fine structure analyses in the vicinity of the primary carbon KLL Auger peak showed that the electronic structure of the TC films resembled that of graphite, indicating that the majority of carbon bonding was of sp 2 type. By heating in the presence of atomic hydrogen, the Auger fine structure changed towards the fine structure of diamond. The results are discussed in terms of the formation of stable sp 3 bonding caused by atomic hydrogen.

Amorphous carbon (a-C:H) films were formed on Cu substrates using a carbide-forming transition metal (Mo, Ta or W) as a catalyst with hot-filament chemical vapour deposition (CVD). This amorphous carbon was transformed into diamond in less than one minute when heated at 1273 K with the hot filaments in a H 2 -0.3%CH 4 atmosphere. During the heating etching and transformation took place simultaneously causing a thinning of the film. After the transformation, the film became transparent and insulating. Scanning electron micrographs of the precursor film and the film after the transformation were taken. Raman spectra of the precursor phase was similar to the reported spectra of a-C:H. Raman spectra of the transformed film, however, showed a distinct diamond peak at a wavenumber of 1331±2 cm −1 (FWHM≤10 cm −1 ). Continuous diamond films with a thickness of less than 1 μm were also grown using the same catalysts in approximately 4.5 h. It was proposed that precursor diamond particles formed at the catalytic surface-Cu boundary and diffused to the Cu surface where they were exposed to atomic hydrogen and then transformed into diamond.

Previous studies of the epitaxial growth of gold by vapor deposition on a variety of substrates have been compiled and listed according to the type of substrate. A short introduction describing the epitaxy process has been included for general reference purposes and some highly promising applications of thin film technology are discussed.