| 摘要 |
PURPOSE:To enable adjustment of distance between a tip portion of a cathode and a tip portion of a Wehnelt electrode without breaking the vacuum by fixing the Wehnelt electrode disposed oppositely to the cathode of a supporting member via a piezo-electric element. CONSTITUTION:An electron rays generating device used for an electron rays exposing device is constructed by supporting a cathode 1 provided with a heater 2 by a supporting member 4 and supporting a Wehnelt electrode 5 opposed to the cathode by the supporting member 4 via a piezo-electric element 7 fit with a cooling metal fitting 7. And a beam 13 is scanned on the member 14 having a cross mark, and it wave shape variation is detected by an electron rays detecting device 15, and the signal is processed to control voltage applied to the piezo-electric element 7 by power source 19. Then, the distance between tip portions of the cathode 1 and Wehnelt electrode 5 can easily be adjusted to the optimum value without breaking the vacuum, and shortage and unevenness of exposure light due to wear of the cathode 1 can be eliminated. |
