| 摘要 |
PURPOSE:To easily produce an antireflection film having lower dependency upon wavelengths by using one kind of material and gradually inclining a substrate at the time of forming the film by sputtering. CONSTITUTION:The film is made continuously porous by gradually inclining the substrate 1, by which the antireflection film is imparted on the substrate at the time of forming the film by sputtering by using a sputtering device. More specifically, the film material having the refractive index lower than the refractive index of the substrate 1 is used as a target 2 and the substrate 1 is held opposite to this target 2 in an initial period of the film formation. The film is formed while the substrate 1 is gradually inclined with the target 2 in proportion to the film formation time. The film is made porous in proportion to the angle theta of this inclination and the refractive index of the film is lowered from the state of the initial period of the film formation, by which the refractive index is continuously lowered. Namely, the refractive index of the film has the gradient that the refractive index of the film lowers continuously toward the film surface from the substrate 1 side. The ideal antireflection film which does not depends upon the wavelengths is eventually obtd. |
