Investigation of Indirect Electrostatic Discharge (ESD) for a Three-Body Problem

An experimental investigation of indirect electrostatic discharge events for an inline three-body geometry was undertaken. Using conducting cylinders of different sizes to model the test system´s conductors, capacitance coefficients were measured, and body potential differences and electric fields were calculated for different geometries of the three floating conductors in close vicinity. The test geometry was chosen to model the approach of the charged human body to an electronic system, which has a neighboring floating conductor; this situation may arise in a manufacturing environment where faulty grounding exists. The parameters studied include body sizes, test geometry, and the relative magnitude and polarity of the charges on the three bodies. An analysis of both first and secondary discharge events is presented and interpreted using a series of charge sensitivity factors. Conditions to support secondary discharges are investigated as a two-body problem