YBaCuO-insulator-normal metal tunnel junctions

YBaCuO-insulator-normal metal tunnel junctions were fabricated and characterized. The thin insulating barrier was formed using a CHF/sub 3/ treatment in a reactive ion etching system. X-ray photoelectron spectroscopy (XPS) measurements and Auger depth profiling confirmed the formation of a fluorinated surface layer. First electrical results are similar to those generally obtained for natural barriers: no well-defined gap but small gaplike structures; existence of a conductance at zero bias; and an increasing conductance, often linear versus voltage, at high biases.<
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