A novel dry etch tool - large area source supported ion etching (LASSIE) - has been developed appropriate for the processing of substrate sizes of presently up to 600X400 mm(2). The plasma is produced through an array of four inductively coupled plasma sources driven by one common 13.56 MHz generator. A second rf generator serves for substrate biasing. Plasma diagnostic data suggest that LASSIE has strong capabilities for future large area etch applications avoiding several drawbacks of conventional reactive ion etching (RIE) in parallel-plate reactors. In particular considerably higher etch rates are to be expected since the plasma densities are roughly one order of magnitude higher than in conventional RIE. In addition the processing will be more flexible and better controlled due to the decoupling of plasma densities and ion bombardment energies. A scale-up with respect to the processing of wafer sizes larger than presently envisaged is easily achieved by the LASSIE concept.