Meniscus lens of synthetic quartz glass and method for the production thereof

摘要

To produce a meniscus lens from synthetic quartz glass for use in a microlithography apparatus, which lens has a first optical surface (7) and a second optical surface (8) with the same direction of curvature as the first optical surface (7), SiO2 particles are formed by oxidation or flame hydrolysis of a silicon-containing starting compound and deposited layer by layer on a substrate to form a cylindrical SiO2 blank which contains layers with a surface normal extending in the direction of growth. To allow such layers, which have however the least possible adverse effect on optical or mechanical properties, it is proposed according to the invention that the blank is plastically worked in a hot forming process under the effect of a deforming force to form a preform (6), which has at least the first curved surface (7) and in which the layers are curved in the direction of curvature, and that the meniscus lens is obtained from the preform.

主权项

1. A method for producing a meniscus lens from synthetic quartz glass for use in a microlithography apparatus, said lens having a first optical surface and a second optical surface with a direction of curvature the same as a direction of curvature of the first optical surface, said method comprising:
forming SiO2 particles by oxidation or flame hydrolysis of a silicon-containing starting compound; and depositing said SiO2 particles layer by layer on a substrate so as to form a cylindrical SiO2 blank that contains layers with a surface normal extending in a growing direction, wherein the blank is plastically worked in a hot forming process under the effect of a deforming force so as to form a preform that includes at least the first curved surface and in which the layers are curved in the direction of curvature, and obtaining the meniscus lens from the preform.