Undoped GaAs crystals showed dislocation cell patterns with cell dimensions of some hundred micrometer orders of magnitude larger than in metals. Nevertheless, the correlation between cell diameter and dislocation density obeys the same Holt relation. Experimental results of dislocation analysis in GaAs were correlated with global computation of the resolved shear stress distribution at growth relevant temperatures and scaled with the universal function d = Kρ−1/2 = αKGbτ−1, where d was the cell size, ρ the dislocation density, K, α the constants, G the shear modulus, b the magnitude of Burgers vector and τ was the resolved shear stress. Samples grown with in situ control of stoichiometry showed nearly no dislocation patterning due to the minimized native point defect content needed for dislocation climb.

Scaling of Dislocation Cells in GaAs Crystals by Global Numerical Simulation and their Restraint by in situ Control of Stoichiometry. P.Rudolph, C.Frank-Rotsch, U.Juda, F.M.Kiessling: Materials Science and Engineering A, 2005, 400-401, 170-4