Deposition of thin BST films in a multi-wafer planetary reactor

Abstract

Abstract We report on the performance of a planetary multi-wafer reactor offering extremely high throughput due to the batch mode processing and a low cost of ownership. This reactor is combined with a liquid delivery system which mixes the liquid precursors from three different sources: 0.35 molar solutions of Ba(thd)2 and Sr(thd)2 and a 0.4 molar solution of Ti(O-iPr)2(thd)2. The composition and microstructure of the films were routinely investigated by X-ray diffraction and X-ray fluorescence analysis. As a direct consequence of the reactor design we obtain high efficiencies for the precursor incorporation in the order of 40%. Furthermore, we obtain a high uniformity of the films over 6 inch wafers. Details of the chemistry and microstructure were investigated by secondary neutral mass spectroscopy and scanning electron microscopy. The electrical film properties are discussed in relation to microstructural properties.