Electronic properties of Al Ga As surface passivated by x 1yx ultrathin silicon interface control layer

The photoluminescence surface state spectroscopy PLS3. method was applied to a study of the surface state distribution NSS., effective surface recombination velocity Seff., electron EFn.and hole EFp.quasi-Fermi levels and band bending VS.on the Al0.33Ga0.67As surface air-exposed and passivated by the Si interface control layer ICL.technique. Using the detailed measurements of the PL quantum efficiency for different excitation intensities, combined with the rigorous computer simulations of the bulk and surface recombination processes, the behavior and correlation among the surface characteristics under photo-excitation was determined. The present analysis indicated that forming of a Si3N4rSi ICL double layer with a monolayer level control.on AlGaAs surface reduces the minimum interface state density down to 1010 cmy2 eVy1 and surface recombination velocity to the range of 104 cmrs under low excitations. q1999 Elsevier Science B.V. All rights reserved