GAAS METALORGANIC VAPOR-PHASE EPITAXIAL OVERGROWTH OVER NM-SIZED TUNGSTEN WIRES

Epitaxial overgrowth of GaAs over nanometer-sized tungsten patterns is studied experimentally. The relationships between the quality of the overgrowth and geometrical parameters, such as crystallographic orient ation, metal width, metal thickness, and grating period, are investiga ted The overgrown structures are characterized using a scanning electr on microscope at top surfaces and at cleaved edges, and by I-V measure ments of Schottky diodes formed between the metal grid and the overgro wn GaAs. It is established that it is possible to obtain a high-qualit y overgrowth layer with a completely planarized growth front within 20 0 nm of growth.