New Fabrication Technique of Quantum Wire Structures with Dimensions Precisely Controlled by the CBE Method

Abstract
A quantum wire structure of GaAs with a line width of below 100 nm has been successfully grown by the chemical beam epitaxial technique using the cleaved face of a GaAs/AlAs multiquantum well (MQW) structure. Before GaAs growth, an ultrafine ridge pattern defined by the (001) MQW structure was made by the thermal etching method. GaAs layers grown on the patterned substrate exhibit a mesa-shaped structure, with sidewalls of (111)A and (1̄1̄1)B facets. This method for making quantum wires is compatible with currently available growth techniques, and is readily applicable to one-dimensional lasers etc.