Doping Effects on Polytypism in Semiconductor Nanowires: A First-Principles Study

Abstract

The effects of dopants on the crystal structure of InP and GaAs NWs are theoretically investigated by means of density functional calculations. The calculated energy differences among various crystal structures with substitutional Zn (C) atoms in InP (GaAs) are found to be similar to those of bulk phase. This indicates that the contribution of dopants to the energy difference among different crystal structures in NWs is negligible. Furthermore, we reveal that the difference in the step-edge formation energy between zinc blende and wurtzite structures with dopants is similar to that without dopant within 0.01 eV/Å. These results thus imply that the role of dopants for the supersaturaion of nanowire formation is crucial to determine the crystal structure of NWs.