This glass reduces deterioration from laser radiation to 1/5 or less relative to that of conventional artificial crystals, and its light resistance against high-intensity lasers, which are used for IC steppers/scanners, etc., has been greatly improved. It is an optimal artificial crystal for polarization optical elements (such as depolarization plates and wave plates), diffractive optical elements, and prism materials.
Applications
- Prisms
Synthetic quartz crystal CQ has considerably improved resistance to intense laser beams used in semiconductor lithography equipment.CQ shows deterioration by laser irradiation equal to or less than 1/5 that of conventional synthetic quartz crystal materials.
Transmittance
General Properties
| Grade | CQ | ||
|---|---|---|---|
| Bubbles and inclusions | IEC758/JIS C 6704 | Ⅰb | |
| CTE (30-100°C) | Z axis | 8ppm/K | |
| X axis | 14ppm/K | ||
| Refractive Index | at 589nm | 1.54 | |
| Laser durability | Solarization | none | |
| Degradation of Transmission | /pls x 0.18Mpls | ＜0.3％/cm | |
| Density | g/c | 2.65 | |
| Heat conductivity (200°C) | K(W/m-℃) Z axis |
6.6 | |
| K(W/m-℃) X axis |
4.1 | ||
- Data is for reference only.
Durability to ArF Irradiation
Conventional Synthetic Quartz Crystal vs. High Laser Durability Crystal CQ (5mJ/cm2/pulse)
△absorption coefficient spectra after ArF irradiation (5mJ/cm2/pulse,1 Billion)
