SCHOTT is soon going to launch the new photosensitive glass “FOTURAN II” in Japanese market. The glass will crystallize after UV exposure and can be used as glass substrate for semiconductor and biotech applications.
After exposure to UV and temperature processes, the glass crystallizes, transformed into a photosensitive glass ceramic (ceramization). Without the efforts of photolithography, the crystallized areas can be etched away with hydrofluoric acid. The SCHOTT product features a high 30:1 glass to crystallized area etch selectivity ratio for easy process.
When lithography is applied to regular glass, etch process develops isotropic and is hard to achieve a high aspect ratio. On the contrary, photosensitive glass only needs to selectively etch away the crystallized area with literally no limitation on aspect ratio, resulting in 20～30μm fine structures.