Gencoa can accurately model the flux distribution from any rectangular magnetron geometry by simulating where on the target surface the erosion occurs and then combining that with a particulate trajectory algorithm to build up a flux map. Typically, most rectangular magnetrons are used combined with substrate movement past the target to produce a good uniformity. In that case the major factor is the length of the target and the target to substrate separation.

As a general rule the extra target length at either end of the substrate should be at least equivalent to the target width. Across the target there is a difference in the flux distribution relative to the width of the target and the target to substrate separation. A typical static flux distribution can be seen below for different geometries.