Effect of microwave ferrite on the density distribution of microwave-superposed inductively coupled plasma

Abstract Inductively coupled plasma (ICP) to which microwaves are superposed produces better characteristics for both density and uniformity than other conventional high-density plasma (HDP) sources. However, the uniformity of the plasma is not adequate yet. So, we propose an approach to improve the plasma uniformity by putting microwave ferrite around the ICP plasma and superposing microwaves to it. The results suggest that the vertical and horizontal distributions of the plasma are improved by optimizing the relations between the location of microwave ferrite and the microwave introducing techniques.