Discussion on the Relationship Between Speed Gradient and Film Thickness in Spin-Coating Film Formation

This article investigates the effect of spin-coating speed gradient on film thickness. Based on fluid mechanics and the Meyerhofer model, experiments have found that as the speed gradient increases, the film thickness decreases. For example, when the gradient rises from 500 rpm/s to 3000 rpm/s, the film thickness drops from 312 nanometers to 205 nanometers. However, an excessively large gradient may lead to uneven film thickness distribution. The article recommends selecting an appropriate gradient based on the target film thickness and adjusting process parameters by considering factors such as solution viscosity and ambient humidity.