Electron diffraction and Raman studies of the effect of substrate misorientation on ordering in the AlGaInP system

We report a systematic study of the effect of substrate orientation on the ordering in the AlGaInP system, including the Al0.52In0.48P lattice-matched ternary case. Four AlGaInP/GaAs/AlInP samples were grown by metalorganic v apor phase epitaxy under identical growth conditions on [100] substrates or ientated 0 degrees, 2 degrees, 10 degrees and 15 degrees either towards the [110] or the [111] axis. The ordering in both the AlInP and the AlGaInP la yers was studied by electron diffraction and the Raman scattering technique . The tendency for ordering decreased with increasing misorientation and is less for (AlxGa1-x)(0.52)In0.48P than for AlInP. The AlInP was found to sp ontaneously order even when grown after a completely disordered AlGaInP lay er. The Raman results show features correlated to the electron diffraction results and hence we conclude that this technique constitutes a reliable no ndestructive means of characterizing this system. (C) 1999 American Institu te of Physics. [S0021-8979(99)06901-7].