摘要 |
<p>In order to restrict a local concentration of an electric field in a conductor layer end portion (11a, 15a) 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 (11a, 15a) of the electrode conductor (3, 6) is melted and smoothened so as to restrict the concentration of the electric field. <IMAGE></p> |