(168a) Particle Adhesion in Microelectronics Processing

As demand grows in the microelectronics industry for smaller, faster, and cheaper devices, optimization of the adhesion of particles to semiconductor surfaces during process steps such as lithography and chemical mechanical planarization (CMP) becomes increasingly important. Proper modeling of these interactions can result in the reduction of defects caused by abrasive damage and remnant particles. This study includes combining the effects of both van der Waals (vdW) and electrostatic double layer forces (EDL) in order to predict the adhesive forces for particles ranging from the micron-scale to the nano-scale. This requires a comprehensive characterization of the geometry and morphology of the particles and substrates to include roughness, which will then be simulated for a range of different orientations such as would be found in real-life particle-substrate interactions. An ?effective? Hamaker constant is obtained by comparing modeled and experimental adhesion force data. In the case of interactions within electrolyte solutions such as CMP slurry, EDL force calculations accounting for the morphologies of rough particles and substrates are included in the determination of the overall force. By using these results, predictions can be made for manipulating the process conditions according to the desired adhesion of various particles throughout the fabrication of microelectronics devices.