The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 21, 1997
Filed:
Nov. 22, 1995
Wataru Ito, Tokyo, JP;
Tadataka Morishita, Tokyo, JP;
Norio Homma, Sapporo, JP;
Yukihisa Yoshida, Tokyo, JP;
Nippon Steel Corporation, Tokyo, JP;
International Superconductivity Technology Center, Tokyo, JP;
Mitsubish Electric Corporation, Tokyo, JP;
Hokkaido Electric Power Co., Inc., Sapporo, JP;
Abstract
A method of making a superconducting thin film of a Y--Ba--Cu--O series material by using a diode parallel plate type sputtering apparatus including a vacuum chamber, a substrate disposed within the vacuum chamber and having a substantially flat surface on which the superconducting thin film is to be formed, and a plate-shaped target functioning as a cathode and disposed within the vacuum chamber to parallelly face to the flat surface of the substrate, the target being made of the same material as the superconducting thin film, a plasma gas being introduced into the vacuum chamber, and a voltage being applied between the cathode and the substrate, wherein the method comprises the steps of applying a high frequency voltage having a frequency higher than 40 MHz between the cathode and the substrate to generate plasma of the introduced gas, superimposing a DC voltage (V) on the high frequency voltage in a polarity that the cathode becomes negative, and setting the DC voltage at a value where the DC voltage is substantially unchanged with variation of a cathode current flowing through the target when adjusting the DC voltage and controlling a value of the DC current while maintaining the DC voltage substantially at the set value.