Analytical modeling of collisionless triple frequency capacitive sheath

A self-consistent model for collisionless capacitively coupled plasma (CCP) sheath driven by triple frequency (TF) RF source has been developed. This work established analytical expressions for sheath parameters based on the assumptions of time independent collisionless ion motion and inertialess electrons. The parameters calculated using the present model are compared with those calculated using a single frequency model and a dual frequency model for time independent collisionless case. The effects of frequency ratio on sheath potential and sheath width are also investigated.