Japan’s Mitsubishi Chemical is to looking at establishing an ultra-high-purity colloidal silica plant at its site in Kitakyushu, Japan, for use as a raw material for polishing agents in semiconductors. The company makes this material through an integrated manufacturing process using ultra-high-tetramethoxysilane. Commercial operations will begin in October 2028.
Colloidal silica is used as a raw material for surface polishing agents for silicon wafers and for chemical mechanical polishing slurries used on the interconnect layers.
They make it possible to achieve high material removal rates while simultaneously flattening the surface at the nanoscale, ensuring impurities are removed and minimising scratches when polishing the wafers’ wiring layers.
CMP of wiring layers requires simultaneous achievement of high material removal rates, nanoscale surface planarization, absence of impurities, and minimal surface scratches. Because the appropriate particle shape and physical properties of colloidal silica vary depending on the material being polished, customization of particle parameters is a relevant formulation variable.
Mitsubishi Chemical’s ultra-high-purity colloidal silica is designed to address this variability: particle size and density can be customized to meet specific process requirements, according to the company. The product is positioned for use in advanced semiconductor node manufacturing, including applications in generative AI chip production and data centre hardware.
The product is manufactured through an integrated process using ultra-high-purity tetramethoxysilane (TMOS) as the starting raw material. According to Mitsubishi Chemical, the use of TMOS at the front end of the process is designed to minimise impurity content in the final colloidal silica, which is critical for wafer polishing applications where trace metal or particle contamination can affect device yield.