| 摘要 |
PURPOSE:To grow a thin-film composed of a homogeneous superconductive material having a desired composition by respectively evaporating at least two kinds of consituent metallic elements or these oxides, controlling evaporation rates independently from separate evaporation source and controlling a foundation temperature while introducing oxygen, controlling an introduction rate into a vacuum device from an oxygen supply source held at a fixed pressure. CONSTITUTION:A sapphire substrate 11 is irradiated with Er, Ba and Cu from Knudsen cells 14 so that growth rates are brought to 1.8nm/min, 5.0 nm/min and 2.1 nm/min by respectively controlling Er, Ba and Cu independently while being heated at a temperature of 650 deg.C through resistance heating. On the other hand, oxygen pressure in a vessel is controlled by adjusting the conductance of a variable leakage valve installed to an oxygen-gas introducing port 17 and a main valve on the exhaust side mounted on the gas exhaust port 18 side in oxygen, and oxygen is introduced into the vacuum vessel 12 so that beam intensity is brought to 6X10<17> atom/sec and the substrate 11 is irradated with oxygen beams. A thin-film composed of an oxide superconductor having the composition of ErBa2Cu3O6.8 approximately can be grown onto the substrate 11 through such operation. A high melting-point metallic element such as Y can be used in place of Er as a constituent element.
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