A novel technique was presented, for the study of strain relaxation in lattice-mismatched hetero-epitaxy, that was based upon the ultra-high vacuum scanning tunnelling microscopy of quenched epitaxial surfaces. Because of the extremely low limit for the detection of single misfit dislocation glide lines of monolayer height in large-scale scanning tunnelling microscopic images, relaxed misfit strains as low as 0.0001 could be detected  in situ. By using this novel method for the study of molecular beam hetero-epitaxial EuTe on PbTe(111), the existence of an initially sluggish strain relaxation process, that was undetectable by means of  in situ  reflection high-energy electron diffraction, was observed. The obtained strain relaxation data revealed the importance of the energetics and kinetics of misfit dislocation propagation and multiplication in the dynamics of the strain relaxation process.

N.Frank, G.Springholz, G.Bauer: Journal of Crystal Growth, 1995, 150[1-4], 1190-5