Electron mobility in AlxGa1-xAs

he electron mobility in AlxGa1-xAs grown by several techniques has been studied to determine whether VPE layers are more highly compensated than comparable LPE layers. The techniques used to grow layers included (1) organometallic VPE using Al(CH3)3, AsH3, and Ga(C2H5)3 or Ga(CH3)3, (2) ''hybrid'' organometallic technique using HCl to reduce C and O contamination, (3) standard AsH3+HCl VPE (GaAs only), and (4) LPE. The mobilities in VPE and LPE AlxGa1-xAs are found to be similar, and to depend strongly on solid composition, x. The temperature dependence of the electron mobility indicates that both compensation and space-charge scattering increase with x and contribute to the reduction of electron mobility.