(100) Si substrates are patterned with arrays of Ge wires ~60 nm in width and ~6 nm in thickness. Pulsed laser induced epitaxy (PLIE) is used in an attempt to fabricate ultrasmall dimension Ge1–xSix wires. After laser irradiation, interesting changes on the surface are observed. In particular, ripples as high as ~30 nm are formed after the 6 nm Ge wires are incorporated into the substrate. The ripples decrease in height with further laser irradiation. The height is a function of the Ge wire width. Nomarski, scanning electron, atomic force, and cross-sectional transmission electron microscopy are used in the analysis. Possible explanations for the growth of the features are discussed.
Journal of The Electrochemical Society, 143(8): 2678-2680