Crystallographic tilting in lattice-mismatched heteroepitaxy: A Dodson–Tsao relaxation approach

Asymmetric strain relaxation and the concomitant misorientation (tilt) of the lattice planes of the epitaxial layer in lattice-mismatched heterostructures is analyzed theoretically. The kinetic relaxation model of Dodson and Tsao [Appl. Phys. Lett. 51, 1325 (1987); 52, 852(E) (1988)] is extended to the growth on vicinal surfaces. We calculate the equilibrium tilt values as well as the evolution of tilt during strain relaxation as a function of material parameters, initial defect densities, and substrate miscut angle. Literature data are interpreted within the framework of the model.