na-adjective, noun which may take the genitive case particle 'no'
ultrahigh purity
Technical term used in chemistry, materials science, and semiconductor manufacturing to describe substances with extremely low impurity levels.
This experiment requires reagents of ultrahigh purity.
Ultrahigh-purity silicon is used in semiconductor manufacturing.
高純度 means 'high purity', a more general term. 超高純度 emphasizes an extreme level of purity, often used in specialized contexts.
Compound of 超 (chō, 'ultra-') + 高 (kō, 'high') + 純度 (jundo, 'purity'). A straightforward modern technical coinage.