| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent a metal gas from being vapor-deposited to a transparent plate without utilizing gas purge or a shutter. <P>SOLUTION: A window structure of a furnace body includes: a transparent plate 31 attached to a side wall part 11a of a furnace body 11; and a heating device 41 for heating an exposed surface 31a of the transparent plate 31 facing the internal space 12 of the furnace body 11. The heating device 41 heats the exposed surface 31a of the transparent plate 31 to a melting point of a metal contained as the metal gas in the internal space 12 of the furnace body 11 or higher. Thus, the vapor deposition of the metal gas to the exposed surface 31a of the transparent plate 31 is prevented, and also even if the metal gas is vapor-deposited to the exposed surface 31a of the transparent plate 31, deposits are removed by melting them by heating. <P>COPYRIGHT: (C)2012,JPO&INPIT |
