Designable Ge Quantum Dots in SiGeO: a Molecular Dynamics Study

Abstract

Due to high carrier mobility and remarkable properties in nanoscale over Si, Ge-based nanoelectronic devices have drawn attention as promising candidate for the next generation CMOS technology. Thus, the study of Ge nanoparticles formation and its applicable ways is essential to develop novel semiconductor devcies. Molecular dynamics (MD) simulation based on empirical interatomic potential is preferred method for handling nanoscale physics, which is the size of modern CMOS devices, due to its lower computational cost than fully quantum mechanics (QM) approaches such as an ab initio calculation. In this work, we report a MD study on the Ge nanoparticle formation in SiGeO coumpounds. Tersoff interatomic potential is used in our simulation and is suitable for Si-Ge-O ternary system. Specifically, amorphous SiO2 (a-SiO2) and amorphous GeO2 (a-GeO2) formation was studied with Tersoff interatomic potential and then, simulation results are compared with other simulation or experimental results to confirm accuracy of Tersoff potential. However, there is no prior parameterization of Tersoff interatomic potential for describing ternary interaction of SiGeO compound and it requires special efforts. We can get parameters for Si-Ge-O bonding using mixing rules. Eventually, Ge nanoparticle formation in SiGe/SiGeO/SiGe layered structure was developed using modified Tersoff interatomic potential parameters. Ultimately, our approach would provide reproducible and realistic guidelines for Ge QD growth.