| 摘要 |
PURPOSE:To improve the memory density with high accuracy and decreased track width by forming a track pit by means of light without mechanical processing of shaped rugged pit. CONSTITUTION:A film is formed uniformly by uniform coating or cheical plating by using any of positive or negative photoresist, a track shaped mask is applied to the film and the film is exposed by light. Further, the rugged pit is formed by the tratment of acid or alkali solution and etching. Tracks transparent and opaque to a light (laser light or monochroic light) are formed alternately onto a disc with high accuracy by using a part without photoresist and a part remained with the photoresist. Further, the deterioration of the photoresist due to secular change is prevented by forming a film made of the said various transparent compound or transparent organic high polymer (PC, PMMA, glass or polymer) on the film 6 as a protecting film. |
