Vapor–Liquid–Solid Growth of Semiconductor Nanowires

We discuss the growth of semiconductor nanowires, with an emphasis on the vapor–liquid–solid growth of III–V nanowires. Special attention is paid to modeling of growth and the resulting morphology, crystal phase, composition, nanowire heterostructures, and statistical properties within the nanowire ensembles. We give a general overview of the vapor–liquid–solid growth of nanowires by different epitaxy techniques and the bases for nanowire growth modeling. We discuss the role of surface energetics in the formation of GaAs nanowires, which has an important impact on the nanowire morphology and crystal phase. A detailed description of the nanowire growth kinetics is presented, including the transport-limited growth, chemical potentials, nucleation and growth of two-dimensional islands, and self-consistent growth models combining the material transport equations with the nucleation rate. The nanowire length and diameter distributions are considered along with the methods for narrowing them to sub-Poissonian values. Ternary III–V nanowires and heterostructures based on such nanowires are discussed, including the relaxation of elastic stress at the free sidewalls and the sharpening of the heterointerfaces. We consider polytypism of III–V nanowires and possibilities to control their crystal phase by tuning the growth parameters.