J. Phys. IV France 11 (2001) Pr3-723-Pr3-730
Microwave plasma enhanced CVD of aluminum oxide films: Influence of the deposition parameter on the films characteristicsH. Hidalgo, P. Tristant, A. Denoirjean and J. Desmaison
Laboratoire de Sciences des Procédés Céramiques et Traitements de Surface (SPCTS), ENSIL, Université de Limoges, UMR 6638 du CNRS, 123 avenue Albert Thomas, 87060 Limoges cedex, France
Thin films of aluminum oxide were deposited on silicon wafers at low temperature by remote microwave plasma-enhanced chemical vapor deposition using an oxygen plasma and a mixture of trimethylaluminum and argon injected in the afterglow. Although the pressure and the total flow rate were low (respectively 2 Pa and 178 sccm), the deposition rate was high (250 nm.min-1) and the films contained only hydrogen as impurity. The most influential parameter on the quality of the film was the temperature which had to reach 550°C to obtain good quality films. A lower pressure made possible a better desorption of the by-products which induced a higher deposition rate and a lower etch rate in a 2%wt hydrofluoric acid solution. In the standard conditions, in presence of a large excess of oxygen (oxygen/trimethylaluminum>18), the trimethylaluminum precursor was fully transformed. The quality of the coatings was almost independent on the microwave power.
© EDP Sciences 2001