GMR Within-Wafer Uniformity

Manufacturing of GMR Thin Films

Reducing Electrode Spacing The integrated model indicates that reduced electrode spacing would significantly improve deposition uniformity. Experiments were conducted at NVE with the spacing being reduced to 1.3 in from the nominal setting of 1.5 in. The results, shown in the graph to the right, indicated that this closer spacing reduced the within-wafer s of hsat by 45% while producing wafers with excellent GMR.

Target Shaping Calculations using the integrated model showed that a concave shaped target would reduce deposition non-uniformity across the wafer, since the reduced spacing at the edges would compensate for the flux of atoms escaping from the plasma boundary. Results from experiments at NVE with a concave shaped target are in agreement, as shown on the figure to the left.

Deposition (and hence film property) uniformity within a wafer has shown significant improvement following recommendations obtained from simulations with the virtual integrated prototype (VIP) model.