Modeling and experimental studies of a transformer coupled plasma (TCPTM) source design for large area plasma processing

Extension of a planar inductively coupled source designed for 200-mm wafer processing to a large area plasma application, i.e., flat panel display manufacturing, has been studied by both computer simulation and Langmuir probe measurements. The large area source utilized multiple inductive elements operated in parallel, thereby generating a planar plasma which was uniform over a large area substrate, e.g., a 600×720 mm panel. Cold plasma simulation of this source using commercially available three-dimensional (3-D) electromagnetic software (Maxwell Eminence, Ansoft Corp.) reveals the spatial distribution of inductive RF power coupling for this source. Langmuir probe measurements of the ion current distribution for the same plasma conditions are in general agreement with the model predictions and confirm that uniform plasmas can be obtained over a large area with this source