Angel G Rodriguez | Universidad Autónoma de San Luis Potosí (original) (raw)

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Papers by Angel G Rodriguez

GaSb and AlxGa1-xSb thin layers were grown on (001) oriented GaSb substrates by liquid phase epit... more GaSb and AlxGa1-xSb thin layers were grown on (001) oriented GaSb substrates by liquid phase epitaxy technique at low temperatures. Until now, there are no previous reports on the growth of this alloy at temperatures lower than 400 °C. The layers were grown from 400 to 250 °C for the ternary layers, and at 200 °C for the binary layers using a supercooling process of 10 °C and a cooling rate of 0.5 °C/min. In addition to that, ternary AlxGa1-xSb layers were prepared at 250 °C for several contact times 1, 5, 10, 40 and 80 minutes, and something similar was done for binary GaSb layers, with contact times of 7.5, 15, 30, 60 and 120 minutes. Infrared reflectance results show the presence of single mode spectra for GaSb layers and two mode spectra for AlxGa1-xSb layers corroborating the growth of the alloys, whereas Raman scattering results show also the single and two mode behaviors of the GaSb and AlxGa1-xSb layers respectively. In ternary layers Raman bands, such as LO-GaSb like mode u...

Advanced Science, Engineering and Medicine, 2013

Journal of Crystal Growth, 2015

Applied Physics Letters, 2014

We present our measurements and model for the reflectancre anisotropy of the (001) surface of pol... more We present our measurements and model for the reflectancre anisotropy of the (001) surface of polar cubic zinc-blende semiconductor in the far infrared. We observe that the relative reflectance difference of both semi-insulating Cr-doped and the n-doped GaAs(001) can reach the value of twenty percents in the far infrared, which is two orders of magnitude higher than the reflectance difference

Spectroscopy Letters, 2014

physica status solidi (c), 2003

ABSTRACT We present our measurements and model for the reflectancre anisotropy of the (001) surfa... more ABSTRACT We present our measurements and model for the reflectancre anisotropy of the (001) surface of polar cubic zinc-blende semiconductor in the far infrared. We observe that the relative reflectance difference of GaAs(001) in the far infrared can reach the value of twenty percents which is two orders of magnitude higher than the reflectance difference of the GaAs(001) in the near-ultraviolet - visible range. The most strong reflectance anisotropy was observed in the optical phonon Reststrahlbande and its vicinity. We relate the observed reflectance anisotropy with the anisotropy of the optical-phonon and plasma damping constants. Such anisotropy can be caused by anisotropic inhomogeneous broadening of the frequencies of the optical-phonon and plasma oscillations polarized respectively along the [110] and directions. This effect can be understood in terms of the lattice-deformation-induced changes of the optical-phonon force constants and electron-effective-mass tensor components. Anisotropic inhomogeneous strain of the lattice can in turn be induced by anisotropic microscopic short-range ordering of point defects (dopants) and dislocations in near-surface regions of noncentrosymmentric zinc-blende semiconductors. The observed giant reflectance anisotropy can be used as a sensitive tool for the far infrared characterization of zinc-blende semiconductors. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Microelectronics Journal, 2003

Journal of Non-Crystalline Solids, 2009

Journal of Crystal Growth, 2013

ABSTRACT In this work, we present a Raman scattering study of GaAs layers grown on (6̄3̄1̄)-orien... more ABSTRACT In this work, we present a Raman scattering study of GaAs layers grown on (6̄3̄1̄)-oriented substrates by molecular beam epitaxy. A set of samples whose morphology sustained different corrugation order were grown by MBE by varying the growth parameters such as temperature and As/Ga flux ratio. We employed polarized Raman spectroscopy using the backscattering configurations Z(XX) , Z(XY) and Z(YY) . According to the calculated dipole selection rules both TO and LO phonons are allowed for backscattering from a perfect GaAs (6̄3̄1̄) crystal, but with the intensity of the TO phonon much larger than that of the LO phonon. However, it is found that the selection rules differ for corrugated samples. Besides, the TO/LO phonon resonances intensity ratio and the LO peak asymmetry depend on the corrugation order of the samples.