Ballistic-electron emission and secondary photoelectron microscopy of the sulfur-passivated Pt-GaP(001) interface

Ballistic emission electron and X-ray photoelectron emission microscopy studies are presented for the sulfur-passivated Pt-GaP(001) buried metal-semiconductor interface. The topographic/ballistic images showed that the roughness of the metal-semiconductor samples after sulfur passivation and Pt deposition is higher than in the as-received substrate. The photoelectron emission microscope microimages showed a significant inhomogeneity as far as the interface chemical environment is concerned. The strongest inhomogeneity appeared to be related to the gallium, and these variations have a subtle effect on the P and Pt signals. These complementary techniques enabled us to correlate the surface topography and the interface transport variations, with the spatially resolved chemical information of the buried Pt-GaP metal-semiconductor interface.