Abstract
The chemical properties of metal/GaAs interfaces formed by the deposition of metals, Au and Ag, onto the GaAs(100) surfaces treated with H2SO4 and (NH4)2Sx solutions, have been investigated using synchrotron-radiation photoemission spectroscopy. Photoemission data demonstrate that As atoms are segregated on the metal overlayer during Au and Ag deposition on GaAs surfaces with native oxide, while the As segregation is suppressed on the (NH4)2Sx-treated GaAs surface which has no native oxide. In the case of Au deposition, we demonstrate that for low coverages of Au the formation of AgGa alloy is suppressed on the (NH4)2Sx-treated surface. The island growth of Ag film and the absence of AgGa alloy during Ag deposition are observed, an indication that no reaction occurs between the Ag and the (NH4)2Sx-treated GaAs substrate. We suggest that the removal of native oxide and sulfur-termination are crucial to the passivation of metal/GaAs interfaces.
Original language | English |
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Pages (from-to) | 441-446 |
Number of pages | 6 |
Journal | Applied Surface Science |
Volume | 130-132 |
DOIs | |
Publication status | Published - 1998 |
Externally published | Yes |
Event | Proceedings of the 1997 4th International Symposium on Atomically Controlled Surfaces and Intefaces, ACSI-4 - Tokyo, Jpn Duration: 1997 Oct 27 → 1997 Oct 30 |
ASJC Scopus subject areas
- Chemistry(all)
- Condensed Matter Physics
- Physics and Astronomy(all)
- Surfaces and Interfaces
- Surfaces, Coatings and Films