Material properties of Ga0.47In0.53As grown on InP by low-temperature molecular beam epitaxy

Undoped Ga0.47In0.53As layers were grown by molecular beam epitaxy lattice matched to InP at substrate temperatures, Ts, in the range from 100 to 600 degrees C. X-ray diffraction indicated a widening of the vertical lattice parameter and a simultaneous increase of the arsenic content at low growth temperature. The epitaxial layers were single-crystalline down to Ts=125 degrees C. The room-temperature residual carrier concentrations and the related mobilities for layers grown below 350 degrees C are strongly affected by Ts, whereas at 77 K an influence of Ts on these parameters is already visible at 450 degrees C. At the very low growth temperatures the epitaxial layers show highly conductive behaviour attributed to defect induced ionized deep centers.