CPC H01J 37/073 (2013.01) [H01J 37/3174 (2013.01); H01J 2237/06333 (2013.01)] | 20 Claims |
1. An electron beam writing apparatus comprising:
a cathode configured to emit an electron beam;
a condition controller configured to change a condition under which the electron beam is emitted from the cathode in a plurality of ways; and
a prediction unit configured to predict a life span of the cathode based on a temporal change in an amount of fluctuation of a beam characteristic of the electron beam to a change in the condition when the condition is changed.
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