This project will develop a first principle method for describing the effects of complex geometry and morphology on the adhesion of micron-scale colloids to substrates. This is of importance in the U.S. semiconductor manufacturing industry. Traditional approaches to describing particle adhesion rely on Derjaguin-Landau-Verwey-Overbeek (DLVO) theory or on approaches using the work of adhesion in conjunction with the Derjaguin-Muller-Toporov (DMT), Johnson-Kendall-Roberts (JKR), or Maugis-Dugdale (MD) models for colloid deformation. These approaches are only applicable for idealized systems.
The proposed approach will modify traditional van der Waals (vdW) force expressions to describe the adhesion in aqueous solution. It will account for complex geometry and morphology of the substrates and colloids and also will include the deformation and roughness of the colloids and substrates. Descriptions of geometrically and morphologically-complex colloid-substrate systems of interest to the semiconductor community will be included. Measurement of the contact adhesion force will be performed with an atomic force microscope (AFM). The colloids are either good model materials or common contaminants in integrated circuit processing (SiO 2 , and Al 2 O 3 ). The substrates are important substrates for integrated circuit processing.
In the semiconductor industry, the proposed approach could find immediate application in wafer cleaning protocols during post-etch processing and post-chemical-mechanical-polishing processing. In the biomedical industry, it could be used to improve implant sterilization processes.
