According to various embodiments, a method of processing a substrate may include: disposing a viscous material over a substrate including at least one topography feature extending into the substrate to form a protection layer over the substrate; adjusting a viscosity of the viscous material during a contacting period of the viscous material and the substrate to stabilize a spatial distribution of the viscous material as disposed; processing the substrate using the protection layer as mask; and removing the protection layer after processing the substrate.