The impact of ground plane size upon the performance of Field-induced Charged Device Model ESD testing systems

Experimental measurements of peak stressing current in a laboratory prototype Field-induced Charged Device Model (FCDM) ESD testing system have revealed a nonlinear dependence upon ground plane area and test module capacitance. This dependence is explained by an expanded equivalent circuit model for the testing system that takes explicit account of the parasitic capacitance between the ground plane on the test head and the underlying field plate. The results of this work underscore the importance of ensuring that the ground plane is sufficiently large to cover the device under test.