Fluid simulation of helicon plasma processors

Summary form only given. We have modified the electrostatic drift-diffusion fluid simulation code INDUCT93 (version 1.30 07/17/94) to include static spatially varying magnetic fields, typically with the B field purely axial at the top (RF heating location) and flaring to nearly purely radial at the bottom (wafer location). It is necessary to add the capability for anisotropic diffusion, since the electrons being strongly magnetized will be close to diffusing only parallel to the B field. The usual axial and radial diffusion terms are modified. We illustrate that false cross field diffusion occurs when the B field lines are curved. For just the diffusion module, with a localized uniform heating region, the straight field line case correctly shows only the region with field lines connected to the heating region comes to a steady state with an increased T/sub e/ over the initial value, whereas the region with field lines not connected to the heating region has a continual slow decay of T/sub e/ in time, resulting from the loss term. In contrast, with our flared B field helicon model, we see increases in T/sub e/ everywhere, clearly an error for the regions with B lines not connected to the heating region. This test case is severe since the heating region is a step function in space, not favorable to numerical differencing accuracy.