FTIR spectroscopy studies of aluminium tri-isopropoxide (ATI) in an rf plasma

Metal oxide films are widely used in a variety of products. Their properties make them interesting for a growing field of applications. Due to their hardness, chemical resistance and low conductivity, they are applied e.g. in the production of cutting tools, in solar cells or in OLEDs. The metal oxide layers can be deposited using plasma-enhanced chemical vapour deposition (PECVD). Thus, the properties of the layer are governed by the plasma induced chemistry. In this work aluminum tri-isopropoxide (ATI) containing plasmas were investigated, typically used for the deposition of alumina based coatings. An FTIR-study of the plasma volume, including the ATI molecules and 6 by-products, has been done for an Ar / ATI and Ar / N2 / ATI gas mixture. The absolute concentration and the degree of dissociation of the ATI-molecules as well as the fragmentation efficiency and fragmentation rate have been calculated and, thereby, exhibit important information about the plasma chemistry.