2002 Volume 2002 Pages 20020024
Ingot annealing is indispensable process for InP single crystal to improve its electric characteristics. One of the technical problems of InP ingot annealing is the increase of dislocation density during its annealing process that affects the performance of electronic devices. A computer code was developed for dislocation density evaluation of a single crystal ingot during annealing process. A dislocation kinetics model called the Haasen-Sumino model was used as a constitutive equation. In this model, creep strain rate is related to the dislocation density, and this model was extended to the multiaxial stress state based on the theory of crystal plasticity. Three-dimensional finite element model was used to take account of crystal anisotropy in elastic constants and specific slip directions. Dislocation density analyses were performed for an InP ingot with 4-inch diameter, and time variations of dislocation density and stress were obtained from this computer code.