IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Dielectrics Tuesday Sessions
       Session DI-TuA

Paper DI-TuA5
Angle-Resolved XPS and Auger Analysis of Ultra-Thin Al@sub 2@O@sub 3@ Films Deposited by Atomic Layer Deposition

Tuesday, October 30, 2001, 3:20 pm, Room 130

Session: High K Dielectrics III
Presenter: O. Renault, CEA/Grenoble-LETI, France
Authors: O. Renault, CEA/Grenoble-LETI, France
D. Rouchon, CEA/Grenoble-LETI, France
L. Gosset, CEA/Grenoble-LETI, France
A. Ermolieff, CEA/Grenoble-LETI, France
Correspondent: Click to Email
Ultra-thin (1-4.5 nm) aluminium oxide (Al@sub 2@O@sub 3@) films prepared by Atomic Layer Deposition on HF-passivated Si substrates were characterized by ARXPS and AES. Results were analysed in terms of chemical quality of the oxide layer as well as physico-chemical characteristics of the intermediate layer, before and after RTP annealing. For both as-deposited and annealed films, Al2p and Si2p line analysis revealed that only Al-O bonds were present (neither Al-Al bonds@footnote 1@ nor silicate-type compounds@footnote 2@ were observed at the interface with the substrate); the films, as well as 50 nm-thick ones, were found to be stoechiometric with O/Al ratios around 1.5. For as-deposited films, decomposition of the O1s line evidenced the formation of Al-OH groups@footnote 3@ during the deposition process; their concentration was maximum at the surface and decreased as the depth probed increased; this additional contribution of Al-OH bonds to the O1s signal was not observed on annealed films. Results gained from both decomposition of the Si2p line at different analysis angles and AES depth profiling showed that an intermediate layer of oxidized Si grows up upon annealing, its thickness being related to that of Al@sub 2@O@sub 3@ and equal to 0.6±0.2 nm for 2.5 nm-thick films; sub-oxides appear to be localized at the Si interface whereas fully oxidized Si forms above. Additional results concerning films deposited on thermally grown SiO2-coated Si substrates will be also presented. @FootnoteText@ @footnote 1@ Yang et al., Surf. Coat. Technol. 131 (2000) 79-83 @footnote 2@ Klein et al., Appl. Phys. Lett. 75 (25), 4001 (1999). @footnote 3@ Alexander et al., Surf. Interface Anal. 29, 468 (2000).