Metalorganic chemical vapor deposition growth of undoped GaAs with a low electron concentration on a Si substrate

We have successfully grown an undoped GaAs layer with a low electron concentration on Si by metalorganic chemical vapor desposition (MOCVD). The back and side edges of the Si substrate were covered with a Si3N4/SiO2 stacked layer to suppress Si incorporation into GaAs by the gas phase transport mechanism during the MOCVD growth. A 3-μm-thick undoped GaAs layer with an electron concentration of 3×1014 cm−3, as low as the electron concentration of a GaAs layer grown on a GaAs substrate, was grown on the Si substrate even at 750 °C.