Background carrier concentration and electron mobility in LPE In1−xGaxAsyP1−y layers

Abstract
Lattice‐matched and nominally undoped layers of In1−xGaxAsyP1−y were grown by liquid‐phase epitaxy on semi‐insulating (100) InP substrates. The background carrier concentration for a range of compositions was about 2×1016 cm−3 when unbaked melts were used, but with prebaking 2.8×1015 cm−3 was achieved. The electron mobility data, obtained over the temperature range 77–300 K using magnetic fields up to 9 T, have been interpreted in terms of polar‐optical phonon, alloy, and ionized impurity scattering. For midrange alloys of this purity, alloy scattering was found to be more significant than ionized impurity scattering. The alloy scattering potential is about 0.6 eV for alloys with y=0.5.