Properties of Y-Ba-Cu-O Thin Films Grown in-Situ at Low Temperatures by Co-Evaporation and Plasma Oxidation
We report on the synthesis and properties of thin films of Y-Ba-Cu-O grown by co-evaporation and plasma oxidation. A differential pumping scheme is used to obtain high oxygen pressure on the substrate surface, while maintaining a low pressure at the sources and rate monitors. This results in as-deposited films which are superconducting at 73K on silicon, 68K on sapphire, and 84K on strontium titanate substrates. These are the highest transition temperatures reported on bare silicon. We present topographic and spectroscopic data obtained with a low temperature scanning tunneling microscope on films that have never been exposed to atmosphere. The films are also characterized by resistivity, critical currents, x-ray diffraction, energy and wavelength dispersive spectroscopy (EDS and WDS), inductively coupled plasma spectroscopy (ICP), SEM and TEM.
KeywordsScanning Tunneling Microscope Thin Film Sample Main Chamber Wavelength Dispersive Spectroscopy Plasma Oxidation
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