Highly Uniform GaAs/AlAs Quantum Wires Grown on [001] Ridges of GaAs(100) Patterned Substrates by Molecular Beam Epitaxy

Highly uniform GaAs/AlAs ridge quantum well (QW) structures have been grown on ridges with various widths of about 0.1–1.3 µ m in the [001] direction on GaAs (100) patterned substrates by molecular beam epitaxy (MBE). A GaAs/AlAs quantum wire (QWR) with the cross-section of about 40± 7 nm (width)× 10–15 nm (thickness) grown on a [001] ridge with width of 0.45 µ m showed a very uniform cathodoluminescence (CL) at 78 K along the QWR. Linewidths of the CL peaks of the QWRs up to 75 µ m in wire length were as small as 20–26 meV. The CL peak intensity from only one GaAs/AlAs QWR was much larger than that from a GaAs/AlAs quantum well simultaneously grown on a flat GaAs (100) substrate when the excitation electron beam was 1 µ m in diameter, indicating the high optical quality of the QWRs.