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公开(公告)号:US20080213163A1
公开(公告)日:2008-09-04
申请号:US12034949
申请日:2008-02-21
摘要: Disclosed is a method for producing a BaLiF3 single crystal by a melt growth method, wherein a raw material melt for said single crystal comprising BaF2, LiF and MgF2 in such amounts that the Ba/(Ba+Li+Mg) ratio by mol is in the range of 0.35 to 0.48 and the Mg/(Li+Mg) ratio by mol is in the range of 0.001 to 0.03. In the case where a BaLiF3 single crystal that is useful as a last lens of immersion exposure tools for producing a semiconductor is produced by a melt growth method using, as a raw material, a melt containing excess Li, the Li component is liable to be precipitated to make the resulting BaLiF3 single crystal opaque, and the light transmittance is deteriorated, but such problems can be solved by the present invention.
摘要翻译: 公开了一种通过熔融生长法制备BaLiF 3 N 3单晶的方法,其中包含BaF 2 N,LiF和MgF 3的单晶的原料熔体, 2(Ba +(Ba + Li + Mg)的摩尔比在0.35〜0.48的范围内,Mg /(Li + Mg)的摩尔比在0.001〜0.03的范围内 。 在用作半导体制造用浸渍曝光工具的最后一个透镜的BaLiF 3 N 3单晶的熔融生长方法中,使用作为原料的含有过量的Li ,Li成分容易析出,使得BaLiF 3 N 3单晶不透明,透光率劣化,但是本发明可以解决上述问题。