GaAs interfacial self-cleaning by atomic layer deposition

• Published in: Applied physics letters Vol. 92; no. 7; pp. 071901 - 071901-3
• Main Authors: Hinkle, C. L., Sonnet, A. M., Vogel, E. M., McDonnell, S., Hughes, G. J., Milojevic, M., Lee, B., Aguirre-Tostado, F. S., Choi, K. J., Kim, H. C., Kim, J., Wallace, R. M.
• Format: Journal Article
• Language: English
• Published: American Institute of Physics 18-02-2008
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.2883956

The reduction and removal of surface oxides from GaAs substrates by atomic layer deposition (ALD) of
Al
2
O
3
and
Hf
O
2
are studied using
in situ
monochromatic x-ray photoelectron spectroscopy. Using the combination of
in situ
deposition and analysis techniques, the interfacial "self-cleaning" is shown to be oxidation state dependent as well as metal organic precursor dependent. Thermodynamics, charge balance, and oxygen coordination drive the removal of certain species of surface oxides while allowing others to remain. These factors suggest proper selection of surface treatments and ALD precursors can result in selective interfacial bonding arrangements.