Patent · US Active

Material, particularly for an optical component for use in microlithography, and method for making a blank from the material

US7691766B2 · kind B2 · utility

0Cited by

6References

15Claims

0Family size

Assignee

HERAEUS QUARZGLAS GMBH & CO. KG · DE

Inventors

Bodo Kuehn · Gelnhausen, DE
Stefan Ochs · Bad Camberg, DE

Key dates

Filing date	Apr 18, 2007
Grant date	Apr 6, 2010
Priority date	—
Expiry date	Sep 9, 2027

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC04B2235/9661
WIPO fieldMaterials, metallurgy
WIPO sectorChemistry

Abstract

The invention is concerned with a material which shows low absorption for UV radiation having a wavelength below 250 nm, low birefringence, high chemical resistance and high radiation resistance and which is therefore particularly usable for making optical components for microlithography. According to the invention the material consists of synthetically produced quartz crystallites which form a polycrystalline structure and have a mean grain size in the range between 500 nm and 30 μm. The method according to the invention for making a blank from the material comprises providing granules consisting of synthetically produced quartz crystals having a mean grain size in the range between 500 nm and 30 μm, and sintering the granules to obtain a blank of polycrystalline quartz.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.