layer on a front face of a semiconductor substrate having an area which is predetermined as a contact and patterning the interlayer insulating layer to open the contact area placing the substrate in a chamber and injecting reactant gas and precursor respectively into the chamber and transforming the gas into plasma gas and causing the plasma gas to react with the precursor to form a single tisin film covering the area predetermined as a contact in another example an apparatus for forming a barrier metal layer in a semiconductor device includes a chamber for defining a process space and having a stage in the process space so that a semiconductor wafer to be processed is seated on the stage a partition for dividing the process space within the chamber into upper and lower sections a reactant gas injector for injecting reactant gas into the upper section of the chamber a precursor injector for injecting precursor into the lower section of the chamber and an rf antenna for supplying rf power to the upper section of the chamber to transform the reactant gas into plasma wherein the reactant gas which is transformed into plasma in the upper section is reacted with the precursor in the lower section to deposit a tisin film on a desired area of the semiconductor wafer to be processed as shown in fig3 an example semiconductor fabrication process proceeds with a series of low pressure chemical vapor deposition processes to form a.