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Good bonding of single-crystal semiconductor thin-film (epifilm) on diamond-like carbon (DLC) thin film formed on the Si substrate (DLC/Si) by intermolecular force at room temperature has been achieved for the first time. Characteristics of super high-density epifilm-LED arrays bonded on DLC/Si are compared with those bonded on polyimide film on the Si substrate (PI/Si). Performance test showed much larger emitted-light-power efficiencies on DLC/Si than those on PI/Si in the larger current-density range. The current-power characteristic curve of the epifilm-LED bonded on DLC/Si was found to saturate at much larger LED-current compared to conventional LEDs on the GaAs substrate. The epifilm-LED on DLC/Si achieved much larger heat-dissipation and higher emitted-light-powers at larger LED-currents.

Desorption of Bi and Ag deposited on Si(100) surfaces has been studied by Auger electron spectroscopy for heat treatment in distilled ozone atmospheres. Bi was desorbed from the Si surface at a substrate temperature T s of 350∼450°C and Ag was desorbed at T s of 500∼570°C. The reflection high-energy electron diffraction (RHEED) patterns for Ag overlayers suggested that three-dimensional Ag(100) layers are formed on Si(100).

A BiSrCaCuO superconducting thin film was prepared in situ by molecular beam epitaxy with nitric dioxide gas (NO2). Metal sources were coevaporated onto the MgO (100) substrate at the substrate temperature of ∼700°C under the background pressure of the growth chamber of ∼5×10-6 Torr. The deposition speed was ∼1.8 Å/s and the thickness of the thin film was ∼3000 Å. The zero resistance was obtained at 65 K without the annealing steps. The quality of the BiSrCaCuO superconducting thin film prepared with NO2 is comparable to that prepared with distilled ozone under identical growth condition except for the distilled ozone flux intensity. Oxidation behaviors of NO2 were studied and are compared with those of distilled ozone.