Temperature dependent polarized-piezoreflectance study of near direct bandedge interband transitions of AlInP2

We report a detailed temperature dependent study of polarized piezoreflecta nce (PzR) for two AlInP2 epilayers that exhibit different degree of orderin g in the range between 23 and 500 K. The polarized PzR measurements showed anisotropic character along the [110] and [1 (1) over bar0] directions for the partially ordered sample. The PzR spectra were fitted using the first-d erivative of a Lorentzian line shape functional form. The direct band-, cry stal field splitting- and spin-orbit splitting to conduction band transitio n energies which are denoted as E-g, E-g + DeltaE(12) and E-g + DeltaE(13) respectively, at various temperatures were accurately determined. The tempe rature dependence of these near direct band-edge critical points transition energies were analyzed by the Varshni expression and an expression contain ing the Bose-Einstein occupation factor for phonons. The parameters that de scribe the temperature variation of transition energies were evaluated and discussed.