Impact of target geometry on deposition uniformity in IPVD system

Summary form only given. The analytical approach using the 2 dimensional diffusion propagator model and analytical 1 dimensional model of sputtered metal thermalization were used to investigate the impact of a target geometry on the deposition uniformity in IPVD system in a pressure range from below 1 Pa to 15 Pa. Simulation results showed an agreement with theoretical expectations: (1) enormous deposition rate increase in a ballistic transport region, and (2) low deposition rate and angle insensitivity in the diffusional transport region. The deposition nonuniformity at 300 mm wafer has been mostly affected at the pressures when an intermediate transport regime is involved. The results of an analytical approach were compared to the 2D numerical plasma fluid model of IPVD in same system configuration (model has included chemistry in Ar+Cu plasma, the electron impact ionization, Penning ionization by excited argon and charge exchange). We include also an impact of the fast Cu neutrals and dependence on the target angle on a radial distribution of the deposition rate in investigated pressure range 1-15 Pa. It was observed that magnetic field of conical annular magnetron required for high target utilization has noticeable plasma nonuniformity impact on the in-situ etch rate, affecting coverage performance inside the features. Novel sweeping magnetic field system for the conical annular magnetron was proposed for metal deposition uniformity improvement and control. The 3D magnetic field structure (sweeping magnetic envelope) was preliminary studied by numerical simulation to optimize proposed solution