It was recalled that one of the technical problems of ingot annealing was an increase in dislocation density during the process. A computer program was developed for the dislocation density evaluation of a monocrystalline ingot during annealing. In the program, temperatures in a single-crystal ingot were used as input data and were obtained from a transient heat conduction analysis of an ingot. A Haasen-Sumino dislocation kinetics model was used as the constitutive equation. The creep strain-rate was related to the dislocation density and the model, which extended to a multi-axial stress state, was incorporated into a finite-element elastic creep analysis for axisymmetrical bodies. Dislocation density analyses were performed for GaAs ingots which were 10 or 15cm in diameter, and temporal variations in the dislocation density, equivalent shear stress and residual stress after ingot annealing were obtained.

Development of Dislocation Density Analysis Code for Annealing Process of Single-Crystal Ingot. N.Miyazaki, S.Yamamoto, H.Kutsukake: Journal of Crystal Growth, 2000, 216[1-4], 6-14