In automotive design, integrated circuits (ICs) take over more and more responsibility for safety relevant functions. For that reason, confidence in the functionality is required to provide fail-safe operation, and thus, a high robustness against environmental disturbances is necessary. An electrostatic discharge (ESD) event is such a disturbance, which can induce vast discharge currents into electronic equipment. The focus of this thesis is the investigation of the impact of ESD on the functionality of ICs during operation. ICs exhibit high complexity and have small structure size, and thus, they are especially vulnerable. Although it is an upcoming requirement for IC vendors to provide ICs which are robust against ESD in operation, investigations on IC level have been lacking and there is barley knowledge about the behaviour of ICs stressed by ESD in operation until now. The goal of this work is to reveal relevant coupling paths, to analyse them by measurement and simulation and to define remedial measures. This has been done for different
test-structures. The influence of different, significant parameters
on the IC’s robustness are discussed, e.g. packaging, die size or circuit design. This
results in a novel fundamental understanding of the coupling paths and enables the
discussion which remedial measures are possible on IC level. This work also presents
remedial design measures and validates them by measurement and simulation.
A further advance is the understanding of the impact of ESD stress on the IC’s supply
and ground rail voltage. ESD can critically disturb the IC’s supply rails. This effect is
especially important, because it can cause functional deviations in any circuit block of
an IC. A new modelling technique is developed, which can predict these supply and
ground rail deviations for future investigations. Again, this supply rail modelling has
been validated against test-structure measurement and simulation.
The key result is that this thesis generates a new understanding of the influence of ESD
on ICs during operation. From this new knowledge design guidelines can be deduced
for the development of ICs with improved robustness against ESD.