Asahi Glass provides polished synthetic fused silica products based on high-quality starting materials and advanced technologies of ultra-high-precision processing, polishing, and cleaning.
AGC’s semiconductor photomask substrates cover a range of 4- to 9-inch sizes, chiefly the 6025 size, with the i-ray and KrF grades, ArF grade, and ArF immersion grade available.
Surface roughness ： Super-polishing Ra ≦0.2 nm possible
Surface defects ： Zero assured for immobile surface defects greater than 0.15μm in size (as tested by an automatic defect inspection machine)
Flatness ： Up to 0.3μm (in-plane) assured for the 6025 size
Large photomask substrates for liquid crystal displays can also be processed.
Diameters up to 300 mm (12 inches) and thicknesses down to 0.25 mm are available.
Typical specifications are shown below. Processing with higher precision is also possible.
|Diameter||φ3”, 4”, 5”, 6”, 8”, 12”|
|Total thickness variation (TTV)||≦3-10μm|