Estudio de fotoluminiscencia de películas de InGaP crecidas sobre substratos de GaAs por el método de epitaxia de fase líquida

Abstract

We have studied the luminescent properties of InGaP films grown on GaAs substrates by liquid phase epitaxy (LPE). Photoluminescence~(PL) measurements were performed in wide temperature (4 -- 250 K) and exciting power density (4 orders of magnitude) ranges for different polarization of the emitted radiation along the [011] and [0$\overline 1 $1] directions. It was found that donor-acceptor transition dominates at low temperature (4K) while the band-to-band transition at higher temperature (250K). The dependence with the excitation intensity shows the characteristic behavior of donor-acceptor recombination. The difference in the spectral peak position for different polarizations is a result of valence-band splitting into a heavy and light hole bands due to lattice mismatch strain. Moreover, the difference of the line shape of the spectra for different polarizations indicates the presence of anisotropy for different crystallographic directions.