Photoluminescence and passivation of silicon nanostructures

Sandia National Laboratories, Albuquerque, New Mexico 87185‐1056
Applied Physics Letters (Impact Factor: 3.79). 12/1994; DOI: 10.1063/1.113036
Source: IEEE Xplore

ABSTRACT A new method was used to fabricate nanometer‐scale structures in Si for photoluminescence studies. Helium ions were implanted to form a dense subsurface layer of small cavities (1–16 nm diameter). Implanted specimens subjected to annealing in a variety of atmospheres yielded no detectable photoluminescence. However, implantation combined with electrochemical anodization produced a substantial blueshift relative to anodization alone. This blueshift is consistent with the quantum confinement model of photoluminescence in porous silicon.

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