Molecular Beam Epitaxy Growth of High-Quality Linear Arrays of InGaAs Ridge Quantum Wires with Nanometer Wire Widths and Submicron Wire Pitches on Patterned InP Substrates

Abstract

Systematic investigations have been carried out to grow InGaAs ridge quantum wire (QWR) linear arrays with nanometer wire widths and submicron wire pitches by selective molecular beam epitaxy (MBE) on patterned InP substrates. Uniformity of QWR arrays was markedly improved by employing pregrowth etching, removing native oxide by atomic-hydrogen-assisted cleaning, and optimizing the V/III ratio. The pitch of array was successfully reduced to the submicron range by scaling down both the mesa stripe patterns on the InP substrate and the epitaxial layer thicknesses properly. InGaAs ridge QWR arrays showed an intense and narrow single photoluminescence (PL) emission peak at 20 K with a full width at half maximum (FWHM) as small as 23 meV. The PL peak of the submicron-pitch QWR arrays showed a large blue shift of 134 meV with respect to that from a reference planar QW grown simultaneously, indicating achievement of an effective wire width of about 10 nm.