Fundamental Design of Chemical Formulations
Chemical formulations are used because of the specific properties of the components in the mixture working in a synergistic fashion. Each component plays of role in the overall performance of the formulation. The key components for stripping and cleaning formulations are the base chemicals, additives, and in some cases, water for semi-aqueous cleaners. Design of chemical formulations according to solubility principles is used to tailor the solvents to the solute. Practical considerations are also given for designing a formulation.
Keywords: chemical formulations, solubility parameters, fluoride-based chemistry, amine-based chemistry, hydroxylamine, semi-aqueous chemistry, surfactants, passivating agents, buffering agents
5.1 Introduction and Overview
The formulations used for stripping photoresist, post-implant and post-etch residue removal (PERR), and post-CMP (chemical mechanical polishing) cleaning and particle removal have a long history. However, designing a chemical formulation to clean integrated circuit devices to accomplish the pre-set process requirements is relatively new. The semiconductor industry has borrowed knowledge from various other industries as it went through its initial growing ...