| 摘要 |
PURPOSE:To enhance size precision, rigidity and ink resistance by half-etching one surface of a photosensitive glass exposed and developed in a certain pattern and etching from the side of other surface masked in a certain pattern with a through hole formed. CONSTITUTION:The opposite side of a masked surface of a photosensitive glass 21 is etched to a certain depth by an aqueous hydrofluoric acid solution. Then an exposure mask 25 having a light shield 25a is applied at a position corresponding to the ring-shaped part 21a of the photosensitive glass 21. Following this procedure, the photosensitive glass 21 is masked with a photoregist 24 after application of such processes as exposure, development and fixing. Next, the etched surface is etched with a material 26 layer of hydrofluoric acid. The opposite side of the previously described etched surface is again etched with an aqueous hydrofluoric acid solution until the initial time etched surface is completely continuous to the second time etched surface. As a result, a through hole 27 is formed in a ring-shaped part 21a. |
