Observations of fractal patterns induced on surface of chalcogenide glass

Properties of chalcogenide glasses were studied. After heat treatment, fractal patterns were found on surfaces of Ge23Se67Sb10 and Ge30Se60Sb10 glasses. According to box counting method, the fractal dimensions are determined as 1.58-1.61, which are similar to that of the fractal crystal GeSe2. By analysis, the main factors for the formation of the fractal patterns are the glass structure and the weak interface energy anisotropy. Comparing the fractal pattern with compact seaweed pattern in undercooled Co-Sn melt, the growth mechanism of the fractal pattern in glass is similar to that in undercooled melt, i.e. the larger undercooling leads to the weaker of the interfacial energy anisotropy, which leads to the formation of fractal structure.