Formation of high-density hexagonal networks of InGaAs ridge quantum wires by atomic hydrogen-assisted selective molecular beam epitaxy

Feasibility of growth of InGaAs ridge quantum wire (QWR) hexagonal network structures by atomic hydrogen (H∗)-assisted selective molecular beam epitaxy (MBE) is investigated for use in novel hexagonal quantum circuits based on the binary-decision diagram (BDD) architecture. The fabricated structures were characterized in detail by SEM, AFM, PL and CL measurements. By using patterned substrates with mesa-pattern directions of 〈1 0 0〉–〈1̄ 1 0〉 and 〈5 1 0〉–〈1̄ 1 0〉 together with optimized H∗-assisted selective MBE, hexagonal networks of the sharp and uniform InGaAs ridge structures were realized down to submicron pitches. Embedded InGaAs QWR hexagonal networks were successfully formed on the ridge structures, giving prospects of realizing a node device density lager than 108 cm−2.