The present invention concerns a method and an apparatus for feeding a gas phase reactant from a reactant source into a gas phase reaction chamber. In the method a reactant which is a liquid or solid at ambient temperature is vaporized from the reactant source at a vaporizing temperature; and the vaporized reactant is fed into the reaction chamber. According to the invention the reactant source and the reaction chamber are located in separate vessels which can be individually evacuated. By means of the invention it becomes possible to change and load new reactant chemical without breaking the vacuum of the reaction chamber.
A process depositing a carbon- and transition metal-containing thin film on a substrate involves placing a substrate within a reaction space and sequentially pulsing into the reaction space a transition metal chemical and an organometallic chemical. Following each chemical pulse, the reaction space is purged, and the pulse and purge sequence is repeated until a desired film thickness is obtained. A preferred deposition process uses atomic layer deposition techniques and may result in an electrically conductive thin carbide film having uniform thickness over a large substrate area and excellent adhesion and step coverage properties.
