| 摘要 |
PROBLEM TO BE SOLVED: To remove hydrocarbon contaminants in the tube by introducing in a plasma-state or activated-state of a plurality of cleaning gases into a tube and exhausting the gas from the tube after irradiating on a sample a charged particle beam deflected by an optical system connected to the tube. SOLUTION: An electron beam generating unit 2 is disposed in upper space of a tube 1, an optical system composed of a first and second apertures 3a, 3b and electrostatic deflecting electrodes 4 is disposed at a lower part of the generating unit 2, and exposure chamber 6 to house samples to be exposed to the electron beam is disposed at a lower part of the tube 1. A mixed gas fed from a first material tank 10 into a first plasma generator 11 to activate the gas by the discharge, which is then fed into the tube. An exhaust pump 17 is connected to the outside of the tube 1 through an exhaust pipe 16. |
