HSQ 700 is an electrically fused quartz glass with further reduced alkali content. Due to the lowered total concentration of Li, Na, and K to typically below 0.2 ppm, HSQ 700 features a higher temperature stability and lower devitrification rate. This makes HSQ700 the preferred choice for the most demanding applications.
Typical trace elements and OH content in quartz glass (ppm by weight oxide)
Low alkali content by particle size of higher purity, alkali metal/OH content (< 0.05 ppm / < 30 ppm).
Products and applications
Semiconductor processes with very high purity requirements.