| 摘要 |
PURPOSE:To obtain a positive temperature coefficient thermistor which is improved in thermal responsiveness by reducing the thickness and caused to have uniform characteristics by realizing a multilayered structure by alternately piling up main constituent films of a specific chemical formula and semiconductor films of one or more specific elements, with the uppermost and lowermost layers necessarily being constituted of the main constituent layers. CONSTITUTION:A multilayered structure is formed by alternately piling up main constituent films 2 of a chemical formula of (Ba1-xAx)TiO3 (A=Sr and/or Pb and x=0.3) and semiconductor films 3 of one or more elements selected out of Bi, Ta, and La, with the uppermost and lowermost films 4 and 2 necessarily being the films 2. Such multilayered structure is formed by sputtering the above-mentioned materials 2 and 3 while a substrate 1 mode of alumina is rotated after the substrate 1 is heated to 350 deg.C. The entire thickness of such multilayered structure is controlled to 1-2mum, with thicknesses of the film 3 and 3rd film 4 being respectively set to 150-200Angstrom which is about one tenth of the main constituent film 2. After the films of a positive temperature coefficient (PTC) thermistor are formed in such way, a 2-layer electrode of Ni 5a and Pt 5b is formed on the films by a sputtering method. |
