Bonding and electronic states of boron in silicon nanowires characterized by an infrared synchrotron radiation beamElectronic supplementary information (ESI) available. See DOI: 10.1039/c5nr00427f

The infrared synchrotron radiation (IR-SR) beamline of SPring-8 as an IR light source was applied to characterize boron (B) atoms in silicon nanowires (SiNWs). The use of an IR-SR beam with much higher brilliance than conventional IR light sources and a wide range of wavenumbers from visible to far IR regions made it possible to detect a local vibrational mode of B in SiNWs. The use of this technique has also made it possible to detect other IR peaks related to transitions of a bound hole from the ground state of a B acceptor atom to excited states, clarifying the electronic state of B acceptors in SiNWs. The first report of B local vibrational peaks and electronic transitions of a bound hole from the ground state of a B acceptor atom to excited states by means of micro-FT-IR measurements using an IR-SR beam.