| 摘要 |
PURPOSE:To perform an ultrafine exposure by forming a reflectivity control layer in a substrate which has a part having a property of passing a light and a part having the prescribed optical reflectivity and setting the reflectivities from the two parts on the substrate to the same value. CONSTITUTION:When an SiO2 film is accumulated as a reflecting layer in a thickness larger than 3,000Angstrom on the back surface of a sapphire substrate and exposed at the exposed part of the substrate at the reflectivity adjusted to approx. 45% in the air, the difference of the reflected light intensities between the exposed part of the substrate and the element forming part can be set to less than 5%, and the two parts can be continuously accurately exposed. Further, even if a reflecting layer of amorphous Si 3 is formed in advance by a plasma vapor phase growing method in a thickness larger than 3,000Angstrom on an insulator substrate 4 and quartz glass 1 and a thin Si film 2 are grown in vapor phase, the entirely same effect as the back surface reflecting layer can be obtained. |
