1.Inside Surface roughness (SEMI F19-0304) Ra≤0.25μm;
2.Oil Residue<0.01mg/ft²;
3.Pure-Water resistivity ≥18MΩ_cm;
4.Particle count:0.1μm particleless than 1 per cfm;
5.Lon leaching check sealed water ion chromatography:below 5 ng/cm ²;
6.Cr/Fe Ratio(SEMI F19-0304) ≥1.5;
7.Cro/Feo Ratio(SEMI F19-0304) ≥2.0;
8.Oxide Layer thickness (SEMI F19-0304) ≥15A