  We study the influence of main compensating defects: As antisites and Mn
interstitials, known to occur in GaMnAs ferromagnetic semiconductor, on its
structural properties. Our experimental results show that there is a balance
between Mn interstitial and As antisite defects, leading to the reduced density
of one type of defect upon increased density of another defect. The significant
differences in the lattice parameters of GaMnAs with the different balance
between these two types of defects were observed. The annealing induced
reduction of GaMnAs lattice constant is inhibited in the samples with large
density of As antisites.
