| 摘要 |
PURPOSE: To obtain a resist patterning method which is suitable to form a high accuracy metal pattern without burrs on a transparent substrate by forming a wedge space between the substrate and the resist film adjacent to the part where the resist film is removed. CONSTITUTION: A LiNbO3 transparent substrate is prepared. The back surface of this substrate is ground with a grinder to obtain about 0.5μm average center light roughness, cleaned with pure acetone or the like and dried to obtain a substrate 2 with roughened lower surface 2a. Then a novolac resin resist is applied to 1.0μm thickness on the upper surface of the substrate 2 to form a resist film 3. Then the resist film 3 in the area where a metal pattern is to be formed is exposed to UV rays of 405nm wavelength for 20sec through a mask. In this process, the UV rays (direct light) 4 are reflected on the lower surface 2a of the substrate 2 so that the resist film 3 is also exposed to the reflected light 5c. Further, the substrate after exposure with UV rays is dipped in a developer to remove the exposed part 6c of the resist film 3. As a result, an aperture 7c having a wedge-like space 12 is formed. |
