Low expansion silica-titania articles with a T_zcgradient by compositional variation

摘要

A glass article for use in Extreme Ultra-Violet Lithography (EUVL) is provided. The glass article includes a silica-titania glass having a compositional gradient through the glass article, the compositional gradient being defined by the functions:
[TiO2]=(c+f(x,y,z)), and[SiO2]=(100−{c+f(x,y,z)}−δ(x,y,z))
wherein [TiO2] is the concentration of titania in wt. %, [SiO2] is the concentration of silica in wt. %, c is the titania concentration in wt. % for a predetermined zero crossover temperature (Tzc), f(x, y, z) is a function in three-dimensional space that defines the difference in average composition of a volume element centered at the coordinates (x, y, z) with respect to c, and δ(x, y, z) is a function in three-dimensional space that defines the sum of all other components of a volume element centered at the coordinates (x, y, z).

主权项

1. A glass article for use in Extreme Ultra-Violet Lithography (EUVL), the glass article comprising a silica-titania glass having a compositional gradient through the glass article, the compositional gradient being defined by the functions:
[TiO2]=(c+f(x,y,z)), and [SiO2]=(100−{c+f(x,y,z)}−δ(x,y,z))wherein [TiO2] is the concentration of titania in wt. % , [SiO2] is the concentration of silica in wt. % , c is the titania concentration in wt. % for a predetermined zero crossover temperature (Tzc), f(x,y,z) is a function in three-dimensional space that defines the difference in average composition of a volume element centered at the coordinates (x,y,z) with respect to c, and δ(x,y,z) is a function in three-dimensional space that defines the sum of all other components of a volume element centered at the coordinates (x,y,z); and
wherein f(x,y,z) is independent of z, and the glass article comprises multidirectional variations in the x,y plane.