| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a high quality calcium fluoride optical fluoride crystal for a lithography/laser element having excellent optical quality for the light of shorter wavelength than 250 nm. <P>SOLUTION: The device for treating the fluoride crystal comprises an enclosure (12); a heating means for heating the internal volume (16) of the enclosure (12); at least one hollow platform (20) delimiting an internal chamber (22) whose upper wall (24) bears at least two independent diffusers (30) each delimiting a cavity (32) able to receive a unitary quantity (100) of the fluoride crystal substance, each of the cavities (32) communicating with the internal chamber (22) of the corresponding platform (20); a reactive gas supply source; means (50, 52, 54) for distributing the reactive gas from the gas supply source to the inside of the internal chamber of each platform; and a means (44) for regulating the pressure of the distributed gas. <P>COPYRIGHT: (C)2003,JPO |
