Test structures and testing methods for electrostatic discharge: results of PROPHECY project

The goal of one PROPHECY subtask was to ®nd a set of realistic test patterns for electrostatic discharge (ESD) and propose an appropriate testing method. Starting with basic test structures, a systematic analysis of the layout parameters dependence of the ESD hardness of various CMOS technologies tested according to the Human Body Model (HBM), Transmission Line Pulser (TLP) and socketed Charged Device Model (CDM) hardness has been carried out. Main emphasis has been given to the correlation between results obtained by the different test methods i.e. HBM and TLP, as well as between HBM and socketed CDM. The results obtained on the basic test structures, which are representative of an analogue technology, are compared (i) with results on optimised test patterns, which more realistically emulate the structure of the actual integrated circuits, and (ii), finally with results on several products. It is shown that the results of a careful analysis of the test patterns can be applied to real pads, and at the end, even to products.