High-resolution synchrotron-radiation photoemission has been used to study the band bending and electronic structure at the Bi/InP interface, which is highly ordered, abrupt, and nonreactive. The measurements, taken at room temperature, show that the band bending is significantly different for the n- and p-type substrates at 1 monolayer (ML) of Bi. The band bending is near-vanishing for the former, which can be attributed to be due to an overlayer nearly free of defects at that coverage, while it remains a large value for the latter. A charge-transfer model is presented, which accounts for the band-bending difference between the n-type and p-type materials. At a high Bi coverage (>7 ML), the Bi/InP interface seems to achieve the Schottky limit.

• Received 6 March 1992

DOI:https://doi.org/10.1103/PhysRevB.46.12818