Design and Certification of High Purity Delivery Systems for Semiconductor Wafer Cleaning Chemicals

The wafer cleaning procedures used in new semiconductor manufacturing facilities require extremely high purity chemicals. Delivering chemicals of this quality requires careful management of the chemicals from their manufacturing site to the points of use (POUs) within the wafer fabrication facility (fab). Chemical management includes proper chemical production, transportation to the wafer fab and design and operation of the chemical delivery system within the fab. This paper describes the technology used to supply 15 different types of chemicals to more than 60 POUs in the TECH Semiconductor wafer fab in Singapore. The certification and continuous monitoring program confirms sub-ppb chemical delivery with particle concentrations of < 3 particles/ml at ≥ 0.2 μm. Several challenges associated with the initial design and installation of the chemical delivery system and their resolution are also described.