PURPOSE: To make a long time operation possible by installing a heating means to heat an ion optical part such as a convergent lens, etc., in a vacuum container and putting a valve as well as a cooling means between a sub-vacuum pump and the vacuum container.
CONSTITUTION: An ion beam apparatus is composed of a heating means 7 to heat an ion optical part and valves 14, 14' and a cooling means 13 put between a sub-vacuum pump 11 and a vacuum container 2. At the time of not operating an ion source 3, the ion source is prevented from becoming high temperature as much as possible and only the ion optical part such as a convergent lens 4, etc., and an insulator are heated to degas positively and the generated gas are positively adsorbed on the cooling surface of the cooling means 13. After that, the sub-vacuum pump 11 and the vacuum container 2 are shut and the vacuum degree of the vacuum container 2 having the ion source 3 is maintained. Consequently, a long time operation is made possible.
SHICHI HIROYASU
ISHITANI TORU
