Electrostatic discharge thermal failure in semiconductor devices

The problem of calculating for electrostatic discharge (ESD) thermal failure is considered by the thermal convolution integral technique. It is shown that the common assumption that threshold failure occurs after five time constants is unjustified and that the simple average power method for assessing threshold parameters is, consequently, invalid. New expressions for the threshold parameters are presented which retain the simplicity of the average power method, yet represent only a small sacrifice of the accuracy (typically 5%) of more complex methods. In addition, the relaxation of the constraints of a pure Wunsch-Bell damage profile and of an exponentially decaying current pulse is considered