Wirelike growth of Si on an Au/Si(111) substrate by gas source molecular beam epitaxy

Ultrafine Si nanowires are grown on an Au/Si(111) substrate using gas sourc e molecular beam epitaxy. These Si wires with cross-sectional dimensions be tween 50 nm and 2 mu m grow mainly with a growth axis parallel to the <111> direction, The growth rate of nanowires is independent of their diameters, i.e.. nanowires with different diameters have the same growth rate. From t he dependence of source gas concentration on the growth rate we conclude th at this independence is a fundamental one even when gas pressure ranges as high as 1 x 10(-4) Torr. This method provides a possible alternative means for fabricating ultrafine silicon quantum wires. (C) 1998 The Electrochemic al Society. S1099-0062(98)03-088-7. All rights reserved.