TY - JOUR
T1 - Nanostructure formation during relatively high temperature growth of Mn-doped GaAs by molecular beam epitaxy
AU - Del Río-De Santiago, A.
AU - Méndez-García, V. H.
AU - Martínez-Velis, I.
AU - Casallas-Moreno, Y. L.
AU - López-Luna, E.
AU - Yu Gorbatchev, A.
AU - López-López, M.
AU - Cruz-Hernández, E.
N1 - Publisher Copyright:
© 2015 Elsevier B.V. All rights reserved.
PY - 2015/4/1
Y1 - 2015/4/1
N2 - In the present work, we report on molecular beam epitaxy growth of Mn-doped GaAs films at the relatively high temperature (HT) of 530 °C. We found that by increasing the Mn atomic percent, Mn%, from 0.01 to 0.2, the surface morphology of the samples is strongly influenced and changes from planar to corrugated for Mn% values from 0.01 to 0.05, corresponding to nanostructures on the surface with dimensions of 200-300 nm and with the shape of leave, to nanowire-like structures for Mn% values above 0.05. From reflection high-energy electron diffraction patterns, we observed the growth mode transition from two- to three-dimensional occurring at a Mn% exceeding 0.05. The optical and electrical properties were obtained from photoluminescence (PL) and Hall effect measurements, respectively. For the higher Mn concentration, besides the Mn related transitions at approximately 1.41 eV, PL spectra sharp peaks are present between 1.43 and 1.49 eV, which we related to the coexistence of zinc blende and wurtzite phases in the nanowire-like structures of this sample. At Mn% of 0.04, an increase of the carrier mobility up to a value of 1.1 × 10 3 cm 2 /Vs at 77 K was found, then decreases as Mn% is further increased due to the strengthening of the ionized impurity scattering.
AB - In the present work, we report on molecular beam epitaxy growth of Mn-doped GaAs films at the relatively high temperature (HT) of 530 °C. We found that by increasing the Mn atomic percent, Mn%, from 0.01 to 0.2, the surface morphology of the samples is strongly influenced and changes from planar to corrugated for Mn% values from 0.01 to 0.05, corresponding to nanostructures on the surface with dimensions of 200-300 nm and with the shape of leave, to nanowire-like structures for Mn% values above 0.05. From reflection high-energy electron diffraction patterns, we observed the growth mode transition from two- to three-dimensional occurring at a Mn% exceeding 0.05. The optical and electrical properties were obtained from photoluminescence (PL) and Hall effect measurements, respectively. For the higher Mn concentration, besides the Mn related transitions at approximately 1.41 eV, PL spectra sharp peaks are present between 1.43 and 1.49 eV, which we related to the coexistence of zinc blende and wurtzite phases in the nanowire-like structures of this sample. At Mn% of 0.04, an increase of the carrier mobility up to a value of 1.1 × 10 3 cm 2 /Vs at 77 K was found, then decreases as Mn% is further increased due to the strengthening of the ionized impurity scattering.
KW - Electrical properties
KW - GaMnAs
KW - High temperature
KW - MBE
KW - Nanostructures
KW - Photoluminescence
UR - http://www.scopus.com/inward/record.url?scp=84930465323&partnerID=8YFLogxK
U2 - 10.1016/j.apsusc.2015.01.228
DO - 10.1016/j.apsusc.2015.01.228
M3 - Artículo
SN - 0169-4332
VL - 333
SP - 92
EP - 95
JO - Applied Surface Science
JF - Applied Surface Science
ER -