EXPERIMENTAL-ANALYSIS OF RIVER PATTERNS IN SILICON BRITTLE FRACTURES

During propagation of brittle cracks in silicon single crystal, steps parallel to the direction of the crack and separated by terraces, are often created. As the crack further propagates, these steps gradually coalesce. This produces the characteristic surface morphology usually identified as a river pattern. An experimental analysis of these river patterns appearing during fractures of silicon single crystals at roo m temperature is presented. The coalescence of the steps and the coars ening of the terrace widths reveal an effective interaction between th e propagating steps. With an interaction between steps supposed to be determined by the size of the terraces, the observed river patterns ar e numerically reproduced.