Investigation of Standing Wave Effects on Plasma Uniformity in CCP via 2D Particle In Cell Simulation

Plasma non-uniformity in capacitively coupled plasma (CCP) systems can cause critical issues in semiconductor manufacturing, such as bowing and incomplete etching. To address this, we developed a two-dimensional axisymmetric Particle-In-Cell (PIC) simulation in cylindrical coordinates to investigate mitigation strategies for plasma non-uniformity induced by standing wave effects. The simulation employs an implicit ADI-FDTD scheme, a modified version of the Finite-Difference Time-Domain (FDTD) method, for electromagnetic field calculations, and incorporates a Monte Carlo Collision (MCC) model for plasma-neutral interactions. The validity of the code was verified by comparing the results of the expanding electron beam benchmark test case with those from previous studies. Furthermore, the results of the PIC simulation for the CCP geometry were compared and analyzed with those of a fluid-based simulation (COMSOL). Ultimately, this study aims to propose effective approaches for controlling high-energy ion distributions and improving plasma uniformity in CCP reactors, thereby contributing to more reliable semiconductor processing, as well as to investigate capacitive heating mechanisms such as bounce (collisionless) heating within the developed simulation framework.