Fused Wafer

“Fused Silica” or “Fused Quartz” which is the amorphous phase of quartz (SiO2). When contrasted to borosilicate glass, fused silica has no additives; hence it exists in its pure form, SiO2. Fused silica has a higher transmission in the infrared and ultraviolet spectrum when compared to normal glass. Fused silica is produced by melting and re-solidifying ultrapure SiO2. Synthetic fused silica on the other hand is made from silicon-rich chemical precursors such as SiCl4 which are gasified and then oxidized in a H2 + O2 atmosphere. The SiO2 dust formed in this case is fused to silica on a substrate. The fused silica blocks are cut into wafers after which the wafers are finally polished.