| 摘要 |
PURPOSE:To prevent a mirror for observing the conditions of an evaporating source to be heated by electron beams in a vacuum vessel from losing its function on account of the exfoliation of the thin layer laminated on the mirror by providing a heating means to said mirror. CONSTITUTION:A gun 3 for electron beams in a vacuum vessel 1 melts the material to be melted in a hearth 4 and part of the evporating particles produced by this melting are stuck and laminated on a substrate 5. In this time, the part near the hearth 4 is reflected on a mirror 6 and is observed by naked eyes through an observation window 7. Here a heating means 8 for the mirror 6 is provided in the rear side of the mirror. In this mirror part, a block 11 contg. a heater 10 as the means 8 is mounted on the rear surface side of a mirror supporting base 9, and the mirror 6 is heated to a suitable temp. by conducting electricity to the heater 10. Then when a thin film is laminated on the mirror 6 by the evaporating particles from the hearth 4, the adhering power of the thin film upon the mirror 6 weakens and the exfoliation of the thin film is prevented. |
