Pressure-induced structural transformations in amorphous semiconductors

Pressure-induced amorphous-to-crystalline transformations in Ge, As and Se have been studied thermodynamically and microscopically. A thermodynamic analysis based on experimental data suggests that the structural transformations in Ge and Se can be regarded as a phase transition and a structural relaxation, and that the transformation in As may be relaxational. There is a correlation between the transformation pressure and the covalent bond energy, but such a correlation cannot be seen in the thermal crystallization temperature.