Nanostructure formation during relatively high temperature growth of Mn-doped GaAs by molecular beam epitaxy

作者：Del Rio De Santiago A; Mendez Garcia V H; Martinez Velis I; Casallas Moreno Y L; Lopez Luna E; Gorbatchev A Yu; Lopez Lopez M; Cruz Hernandez E^*

来源：Applied Surface Science, 2015, 333: 92-95.

DOI：10.1016/j.apsusc.2015.01.228

• MBE
• GaMnAs
• Nanostructures
• Photoluminescence
• Electrical properties
• High temperature

In the present work, we report on molecular beam epitaxy growth of Mn-doped GaAs films at the relatively high temperature (HT) of 530 degrees 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 x 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.

• 出版日期2015-4-1