posted on 2015-01-14, 00:00authored byProkhor A. Alekseev, Mikhail S. Dunaevskiy, Vladimir P. Ulin, Tatiana V. Lvova, Dmitriy O. Filatov, Alexey V. Nezhdanov, Aleksander I. Mashin, Vladimir L. Berkovits
Surface nitridation by hydrazine–sulfide
solution, which is known to produce surface passivation of GaAs crystals,
was applied to GaAs nanowires (NWs). We studied the effect of nitridation
on conductivity and microphotoluminescence (μ-PL) of individual
GaAs NWs using conductive atomic force microscopy (CAFM) and confocal
luminescent microscopy (CLM), respectively. Nitridation is found to
produce an essential increase in the NW conductivity and the μ-PL
intensity as well evidence of surface passivation. Estimations show
that the nitride passivation reduces the surface state density by
a factor of 6, which is of the same order as that found for GaAs/AlGaAs
nanowires. The effects of the nitride passivation are also stable
under atmospheric ambient conditions for six months.