The interfacial chemistry and geometry of Au/oxidized GaAs has been investigated using monochromatic X-ray photoelectron spectroscopy (XPS). Both Au-deposition and interface characterization were performed in situ in an ultra-high vacuum XPS chamber. At the initial stage of Au deposition, the pre-formed surface bonding state of As-O prior to Au deposition was completely changed into thermodynamically more stable Ga-O bonding with the kinetic and condensation energies released from Au deposition. The irradiated Au atoms on the GaAs surface produced a mixed state with GaAs. The composition of this Ga-As-Au mixed phase was initially excess-As GaAs due to the liberated As through the bonding transition of oxides. With the successive deposition of Au it gradually changed to excess-Ga state because of the high volatility of As. In particular, this mixed phase was revealed to locate between Ga oxides and Au overlayer. Based on the layered structure model, the quantitative simulation on the Au/GaAs interface could elucidate the resultant bonding-layered structure of interface; Au/Ga-As-Au mixed layer/Ga oxides/GaAs.
|Number of pages||5|
|Journal||Thin Solid Films|
|Publication status||Published - 1999 Nov 1|
|Event||Proceedings of the 1999 26th International Conference on Metallurgic Coatings and Thin Films - San Diego, CA, USA|
Duration: 1999 Apr 12 → 1999 Apr 15
Bibliographical noteFunding Information:
The authors wish to acknowledge the financial support of the Korea Research Foundation made in the program year 1998.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry