| 摘要 |
PURPOSE:A low-expansion glass that is obtained by using SiO2, Al2O3, B2O3, MgO, ZnO, BaO, Na2O in a specific proportion, thus being suitable for use in photoetching mask. CONSTITUTION:The objective low-expansion glass is composed of 55-68wt% of SiO2, 15-24wt% of Al2O3, 2-8wt% of B2O3, 3-10wt% of MgO, 0.3-10wt% of ZnO, 0-3wt% of BaO, 0-2wt% of Na2O and has (Al2O3+B2O3)/(MgO+ZnO+ BaO+Na2O) of 0.9-11 in moles. Further the molar ratio of Al2O3/B2O3 is preferably 1.4-8. The resultant glass has low expansion, and a pattern of high integration can be drawn, because it is low in expansion. Further, it can sufficiently stand etching and cleaning and the violet rays suitable for photoresists can be well transmitted. |
