Investigations of the INductively Coupled Array (INCA) discharge

Operation of inductively coupled plasmas at low pressures and over large areas is desirable. However, upscaling of standard sources is problematic and in addition at low pressures standard Ohmic heating becomes inefficient. A novel concept is the INductively Coupled Array (INCA) discharge which provides tailored collisionless, stochastic electron heating at low pressures. The concept is based on a large lattice of vortex fields, which heats electrons at certain carefully designed resonances in velocity space. Experimentally the concept was realized using a 6x6 array of small planar coils. Due to the lattice nature, upscaling of the discharge is easily possible. Its operation was tested in atomic and molecular gases, including electronegative, processing gases. The plasma parameters were measured using a combination of diagnostic methods. Electrical properties of the discharge (current-power characteristic, electric field structure) were also studied with the goal of investigating and optimizing the efficiency of the discharge. Here an overview of the various results on this discharge and its key properties are presented.