Formation of high-density GaAs hexagonal nano-wire networks by selective MBE growth on pre-patterned [formula omitted] substrates

Abstract

Attempts were made to grow high-density GaAs hexagonal nano-wire networks on (0 0 1) patterned substrates by selective molecular beam epitaxy. To form a hexagon, 〈 1 ̄ 1 0〉 - and 〈5 1 0〉 -directions were combined. By the growth of straight wire arrays in each direction, the growth mode, conditions and mechanism were investigated. The wire width was shown to be determined for both directions by the facet boundary planes resulting from the growth rate difference on different facets. By optimizing growth conditions, highly uniform and smoothly connected hexagonal nano-wire networks with a density of 3×10 8 cm −2 were successfully formed.