| 摘要 |
An alkali-free glass composition for a photoetching mask is described, which comprises, all by mol, 55 to 65% SiO2, 7 to 11% Al2O3, 1 to 11% PbO, 7 to 20% CaO, 3 to 13% MgO, 3 to 13% ZnO, 0 to 3% ZrO2, 0 to 3% F2, 0 to 5% As2O3, and 0 to 5% Sb2O3. This glass is free from defects such as pinholes, has a relatively low coefficient of thermal expansion and contains no air bubbles, and a photoetching mask composed of the glass composition. |
