BI-INDUCED ELECTRONIC STATES AT THE INTERFACE WITH N-TYPE AND P-TYPE GAAS(110)

The electronic transitions of ordered Bi monolayers grown at room temperature on n- and p-type doped GaAs(110) were studied by high-resolution electron energy loss spectroscopy. The absorption edge of the semiconducting Bi monolayer was measured and a band gap of 0.65 eV is estimated. A new absorption feature is shown, particularly evident on p-doped GaAs, and its origin can be related to states generated by the dangling and broken bond acceptor-like states located at the regular dislocation arrays in the Bi overlayer.