Direct band gap structures on nanometer-scale, micromachined silicon tips

The selective deposition of compound semiconductors on single crystal silicon tip arrays produces optical quality, direct band gap materials on the silicon nanostructures. We demonstrate using the organometallic vapor phase epitaxy of GaInP that the direct band gap semiconductor nucleates selectively on the silicon tips. The structural properties of the tips (whose radius of curvature is approximately 10–20 nm) are unaltered by this chemical vapor deposition process. Furthermore, intense band edge emission from the GaInP is observed with an external electron beam or laser stimulation indicating a good crystal quality for the three dimensional epitaxial structures.