Photoemission from the Sr/Si(001) interface

The growth of Sr on n-type Si(001) was studied in detail for coverages betw een 0 and 1 monolayer (ML) using core level photoemission spectroscopy. In a similar manner, the Sr saturation coverage was studied in the 600-925 deg reesC temperature range. Data analysis was carried out by a method that all ows accurate determination of the band-bending shifts. Using this method it is possible to pinpoint the formation and destruction of chemical species from bungled core level photoemission data without needing to know details of the chemical composition of the spectra. Through this analysis it was es tablished that the interaction between Sr and Si breaks down the binding en ergy difference between upward and downward Si dimer atoms. In addition, it was found that the saturation coverage exhibits a clear plateau at 1 ML ar ound 650 degreesC, and a slope change at 1/3 ML around 850 degreesC. The su rface band bending suffers a discontinuous increase as the Sr coverage surp asses 1/2 s ML and as the low energy electron diffraction symmetry changes from [2x3] to [2x1]. (C) 2001 American Institute of Physics.