Microscopic Study on the Work Function Reduction Induced by Cs-Adsorption

Asawin Sinsarp, Y. Yamada, Masahiro Sasaki, Shigehiko Yamamoto

Japanese Journal of Applied Physics · 2003 · 22 citations · 4 references

Concepts

Abstract

The effects of Cs adsorption on Pt(111) and Si(111)-(7×7) surfaces have been investigated using the local tunneling barrier height (LBH) measurement with scanning tunneling microscope (STM). LBH has been evaluated from the tunneling current versus tip-sample gap distance (I-z) characteristic measurement. The histograms of LBHs obtained from the surfaces with different Cs coverages imply that the Cs adsorption effect on reduction in microscopic work function extends over a long distance beyond the classical picture. We conclude that the long-range modification in electronic structure of the substrate due to the presence of Cs atoms may be responsible for this long-range effect.

References

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