Implications of a localised defect model for wafer level reliability measurements of thin dielectrics
Abstract In this paper a simple model of an oxide defect as a region of localised oxide thinning is used to explore the relationship between the most commonly used measurements of dielectric reliability. For each measurement it shows how the measured parameters depend on the area and effective thickness of the defect. The work shows that in constant voltage and ramped voltage stress the area and thickness of the defect may be easily separated in the measured parameters. However, in constant current and ramped current measurements all measured parameters are dependent on both area and thickness which makes the extraction of area and thickness more difficult. It is shown that, in order to be able to project from one measurement to any other, the defect area and thickness must be determined. In particular, if projections of charge to breakdown are required then the use of a model which only includes defect thinning as proposed by Lee et al, [1], is not sufficient.