An efficient algorithm for shadowing effect simulation under hexagonal lattice-based model

This paper introduces an efficient algorithm for simulating the shadowing effect in hexagonal-lattice networks, addressing a critical gap in existing methods that are limited to cubic-lattice models. The shadowing effect significantly influences roughness development in processes such as film growth and plasma etching but has previously been impractical for hexagonal lattices due to its computational complexity. The proposed algorithm dramatically reduces computational load by strategically reducing the calculation dimensionality from three-dimensional (3D) to two-dimensional (2D) and handling the misaligned odd and even layers separately. This enables simulations on personal computers, with the typical simulation time decreasing from several days to less than one hour (achieving >100\times acceleration). Validated simulations show consistent results with cubic-lattice models in both growth (roughening) and etching (smoothing) scenarios, while demonstrating superior symmetry in roughness formation. The work facilitates broader applications of shadowing simulations and integration with other hexagonal-lattice-based mechanisms.