Tunable visible and near-IR emission from sub-10 nm etched single-crystal Si nanopillars.

Nano Lett

Applied Physics Department, California Institute of Technology, 1200 East California Boulevard MC 200-36 Pasadena California 91125, United States.

Published: November 2010

Visible and near-IR photoluminescence (PL) is reported from sub-10 nm silicon nanopillars. Pillars were plasma etched from single crystal Si wafers and thinned by utilizing strain-induced, self-terminating oxidation of cylindrical structures. PL, lifetime, and transmission electron microscopy were performed to measure the dimensions and emission characteristics of the pillars. The peak PL energy was found to blue shift with narrowing pillar diameter in accordance with a quantum confinement effect. The blue shift was quantified using a tight binding method simulation that incorporated the strain induced by the thermal oxidation process. These pillars show promise as possible complementary metal oxide semiconductor compatible silicon devices in the form of light-emitting diode or laser structures.

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http://dx.doi.org/10.1021/nl102140kDOI Listing

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