TECH Center
Top 3 Considerations for Choosing Ultra-High Purity Valves in Semiconductor, Pharma & Gas Systems
As one of the indispensable equipment in industrial production, valves encounter many problems from selection, use to maintenance. The selection of valves is a core component in high-precision fields such as gas systems, semiconductor manufacturing, photovoltaics, and biomedicine, which directly affects gas purity, system safety, and process stability. Unlike ordinary industrial valves, the core demands of ultra-high purity valves are "zero pollution, zero leakage, and low dead volume". Therefore, this article hopes to help everyone by considering which three main factors should be considered when selecting.
Based on the scenario, clarify the core selection indicators, ensure that the material meets customer standards and the requirements of the scenario and SEMI standards, reduce leakage rate in the pressure holding direction, and control is indispensable. Different medium characteristics also mean that gas characteristic selection is a systematic project.
In addition to prioritizing material cleanliness, it is also necessary to clarify parameters such as valve seat, valve body panel, and joints, and provide specific requirements for hole number, size, and interface. How to prioritize cleanliness? Components in contact with gas should avoid releasing particles, metal ions, or organic pollutants. For example, 316L stainless steel is commonly used for valve bodies (requiring electrolytic polishing EP treatment, with an inner wall roughness Ra ≤ 0.8μ to reduce particle adsorption); Priority should be given to PTFE/PCTFE/PFA and other perfluorinated materials, as well as VESPEL with longer lifespan, for sealing components
Of course, in addition to qualitative aspects, especially in terms of process quantification, low dead volume is the main factor in cavity design and cannot be ignored. Factors such as not only pressure range---for low-pressure systems (<0.5 MPa), but diaphragm valves are also the preferred selection. but also related to flow requirements, degree of automation, and temperature range should also be taken into the selection process.