| 摘要 |
PURPOSE:To control thickness of a ZnS film with high pression, to raise hardness of a BaF2 film, and to obtain a filter of superior performance with good production efficiency in an 1R filter having the ZnS film and the BaF2 film, by regulating a substrate temp. of each film within a specified range during vapor deposition. CONSTITUTION:A ZnS layer, a Ge layer and a ZnS layer, a BaF2layer or a ZnS layer, and a Ge layer are alternately laminated in plural times and finally a BaF2 layer on a substrate to form an IR filter. At that time, the temp. of the substrate is maintained during the vapor deposition of the ZnS layer and the Ge layer at 100-150 deg.C to prevent a monitor from being made incorrect due to temp. difference between the substrate for monitoring film thickness arranged near the substrate, and the ZnS, resulting in causing mistake in control of thickness of the vapor deposition film. The substrate temp. is maintained during vapor deposition of the uppermost BaF2 film at 300-400 deg.C to avoid opacification of the film, thus obtaining a film having high surface hardness. |
