Theoretical determination of contact angle in quantum dot self-assembly

Abstract

We have established an analytic thermodynamic theory to elucidate the evolution of contact angle upon the quantum dot (QD) self-assembly. It is found that the balance between surface energy and elastic relaxation energy plays a crucial role in the determination of contact angle in the heteroepitaxial system. The size-dependent surface energy determines a low contact angle in the QDs with small volume at the initial stage of growth, while the elastic relaxation energy becomes more significant and induces a high contact angle in the QDs with large volume.