Analysis of Dislocation Density in Pb(1−x)SnxSe Grown on ZnTe/Si by MBE
The growth of (211) Pb(1−x)SnxSe on Si is achieved with a thick ZnTe buffer layer. The obtained films are specular, but contain widely dispersed void defects. Because the lattice misfit between Pb(1−x)SnxSe and ZnTe is small, dislocation density values on the order of 106/cm2 in the Pb(1−x)SnxSe are obtained. The variation of the dislocation density as a function of Pb(1−x)SnxSe thickness, h, is analyzed in terms of dislocation annihilation. The analysis predicts an inverse quadratic dependence of dislocation density on h, and quantitative agreement with experimental measurements of the dislocation density is obtained.