A Simple Method for Evaluating Flaw Distributions Responsible for Size Effects in the Strength of Small-Scale Silicon Specimens

A simple means of deconvoluting the size distributions of fracture-controlling flaws from Weibull strength plots for small-scale specimens is proposed. The method makes use a power-law distribution function, empirical in form but self-consistent with a conventional two-parameter Weibull probability distribution. Literature data for single-crystal silicon beam specimens covering a range of widths from mm to nm are analyzed according to this procedure. The analysis indicates a reduction in scatter in addition to increase in strength with diminishing specimen size, and quantifies a systematic tightening in flaw distribution associated with refinement in fabrication method.