A method for chemical vapor deposition comprises providing a thin layer of silicon on the surface of a dielectric-covered substrate prior to depositing a tantalum-based barrier layer from a mixture of a vapor-phase reactant comprising a tantalum halide and a reducing gas. Integration can be achieved on a one-time basis. The connector portions include electrically conductive portions that mate to enable communication andor transmission of power signals between the component module and the computer system. The keypad has an opening in the user interface area for receiving a speaker, and a navigation input key may be positioned over the speaker. This system is capable of delivering positive and negative pressures to the airway of a patient by including a blower as the source of breathing gas.