Effect of metal interaction on the Schottky barrier height on adsorbate-terminated silicon surfaces

Through the use of adsorbate-terminated semiconductor (ATS) surfaces, the Schottky barrier heights (SBH) for the Ag/Si(1 1 1) and Au/Si(1 0 0) were recently found to be significantly modified. In the present work, this “partisan interlayer” (PI) approach is studied systematically for selected stable ATS surfaces of Si and with metals with widely different work functions. When viewed in combination with previous data, these new results highlight the varied effectiveness of the ATS surfaces used, which depends critically on the inertness of the ATS against metal interaction. Electrical characteristics are interpreted through a simple model for interface charge transfer to suggest that the As-terminated Si(1 1 1)1 × 1, with a nominal interface behavior parameter (S-parameter) of ∼0.53, is most promising among the ATSs. Additionally, the formation and characterization of the ATS surfaces and the scientific basis of the PI approach are discussed in detail. The implications of these results for applications and the understanding of the formation of SBH in general are also discussed.