ELECTRON GUN FOR ELECTRON BEAM EXPOSURE DEVICE

摘要

PURPOSE:To improve brightness and the throughput of an exposure device by accelerating an electron beam from an LaB6 cathode through an anode to which the higher voltage than the required acceleration voltage is applied and decelerating this electron beam through the anode to which required acceleration voltage is applied. CONSTITUTION:A secondary anode 8 is arranged between a first anode 5 and a cathode 1 (and a Wehnelt electrode 4) and a high voltage power supply 9 with the polarity shown in the figure is connected between this anode 8 and the first anode 5. Then the higher acceleration voltage V2 than the voltage V1 of the first anode 5 is applied to the second anode 8 and an electron from an LaB6 cathode 1 is accelerated through the second anode 8 and then this accelerated electron beam is decelerated through the first anode 5. As a result, the brightness of an electron gun is exceedingly increased and the throughput of the electron beam exposure device can be improved.