| 摘要 |
PROBLEM TO BE SOLVED: To provide a method with which even when charge-up that makes a deposit in a processing chamber a primary cause is generated, electron beam irradiation treatment to a grain oriented silicon steel plate is appropriately performed.SOLUTION: In a processing chamber that is maintained in a low pressure atmosphere, when a surface of a grain oriented silicon steel plate is irradiated with an electron beam, and subjected to magnetic domain fragmentation treatment, pressure of a beam passage region in the processing chamber is raised according to increment of an occurrence frequency of arcing in irradiation of the electron beam. |
