Nonvisible Material Degradation by Physical Cleaning

The semiconductor industry relies heavily on physical cleaning processes such as high-velocity sprays to remove particles from wafer surfaces. Although these methods effectively detach particles, they can also induce subsurface damage, particularly nanoscale cracks that remain undetectable by conventional inspection techniques. This study presents a comprehensive investigation into the mechanisms behind barely visible material degradation caused by physical cleaning sprays. Polymer films and silicon substrates were used as test vehicles. A chemical revelation method was developed to expose and quantify nanocracks. The results show that high-velocity sprays generate damage patterns that depend on droplet kinetic energy, spray parameters, and substrate properties. The paper discusses the implications of these findings for process optimization and device reliability, and it emphasizes the need for precise control of physical cleaning energy.