Role of O₃ and OH^· Radicals in Ozonated Aqueous Solution for the Photoresist Removal of Semiconductor Fabrication

Abstract

The role of direct oxidation by aqueous O₃ and advanced oxidation by OH^· in the removal of photoresist was studied by chemical kinetic simulation and experiments of O₃ reactivity and decomposition in homogeneous aqueous solutions. O₃ is the main species responsible for the removal of conventional photoresist in the ozonated water cleaning process, and the timing of initiator addition to ozonated water is important to maintain high O₃ concentration. Simulation using t-butanol implies that maintenance of a high OH^· concentration is required to remove highly implanted photoresists that O₃ itself cannot easily remove.

Keywords:

• Ozone
• Semiconductor Applications
• Photoresist
• Ultrapure Water
• t-Butanol