GaAs pyramidal microtips grown by selective liquid-phase epitaxy

We present a simple selective liquid-phase epitaxial growth of GaAs pyramidal microtips for integrated scanning near-field optical microscopy sensors. The technique comprises oxide mask formation, openings creation, and liquidphase epitaxial growth. SiO2 mask is firstly formed on (0 0 1) GaAs substrate by liquid-phase deposition, periodic square windows are then created in the mask using photolithography and wet etching, and GaAs microtips are finally grown on the opening areas by liquid-phase epitaxy. Scanning electron microscopy images show high quality of the pyramidal microtips bounded by four equal {111} sidewalk. This differs greatly from those drawn from selective metalorganic chemical vapor deposition. (C) 2004 Elsevier B.V. All rights reserved.