The fractal approach for the evaluation of microdefects in silicon

The fractal properties of the cluster of microdefects in the subsurface damaged layer of a silicon monocrystal have been experimentally investigated. The experiments were carried out with common silicon substrates with artificial heterogeneity introduced by ion implantation. It was discovered that thermal annealing changes the fractal dimension of the cluster under investigation, The connection between the value of the fractal dimension and the bulk microdefect density in the cluster was established, For the first time it was demonstrated, based upon the property of selfsimilarity, that the fractal dimension may be evaluated by means of the radial distribution of values of condenser photo-EMF signals, a measurement that greatly simplifies the investigation of fractal objects in general.