Undoped GaAs with a Low Electron Concentration Grown on Si by Mocvd

We have successfully grown undoped GaAs of very high resistivity on Si by MOCVD. The back and side edges of the Si substrate were coated with a Si 3 N 4 /SiO 2 stacked layer to suppress Si incorporation Into GaAs by the gas phase transport mechanism during MOCVD growth. A 3- μm-thick GaAs layer was grown on this Si substrate at 750 °C in an atmospheric MOCVD reactor using the two-step growth technique. The electron concentration measured by a Polaron C-V profiler is 3xl0 l4 cm −3 , as low as that of GaAs grown on GaAs substrate, up to the depth of 1.5 μm from the surface.