THE GAMMA(C)-GAMMA(V) TRANSITION ENERGIES OF ALXIN1-XP ALLOYS

The transition energies at 20 K for the Gamma(6c)-Gamma(7v) (electron- heavy hole). (E-s(hh)(x)) and for the Gamma(6c)-Gamma(6v(I)) (electron -light hole) (E-s(lb)(x)) of strained and disordered AlxIn1-xP (0.43 l ess than or equal to x less than or equal to 0.62) on GaAs substrates were measured using a photoreflectance method. They are expressed as E -s(hh)((x)) = 1.488(+/-0.020) + 2.30(+/-0.04).x, and E-s(lh)(x) = 1.73 8(+/-0.030) + 1.81(+/-0.06).x(eV). The Gamma(6c)-Gamma(8v) transition energies for unstrained layers (E,(ar)) were also measured at 20 K as Eu (x) = 1.418(+/- 0.007) + 2.42 (+/- 0.01).x(eV). The unstrained samp les were InP, Al0.53In0.47P on a GaAs substrate and Al0.73In0.27P On i t GaAs0.61P0.39 substrate. The shift of the transition energies due to stress was obtained from these transition energies. The hydrostatic a nd shear deformation potentials for AlxIn1-xP alloys were calculated t o be -5.23(+/-0.60)eV and -1.67(+/-0.26) eV by comparing the experimen tal results and the theoretical formulae.