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:
Jan. 07, 2003
Filed:
Sep. 05, 2000
Junpei Kusukawa, Hitachi, JP;
Ryozo Takeuchi, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In order to restrict a local concentration of an electric field in a conductor layer end portion of an insulating circuit board and increase a partial electric discharge starting voltage, thereby improving an insulating reliability of the insulating circuit board and a power semiconductor apparatus employing the same, the present invention provides a method of manufacturing a insulating circuit board comprising the step of applying a voltage between the circuit patterns of the insulating circuit board in an atmospheric or depressurized gas so as to allow the circuit board to discharge electricity, or irradiating a laser beam, thereby a projection shape of the end portion of the electrode conductor is melted and smoothened so as to restrict the concentration of the electric field.