| abstract |
A technology is provided which allows, in a coupling portion obtained by burying a conductive material within a coupling hole bored in an insulating film, the removal of a natural oxide film on the surface of a silicide layer which is present at the bottom portion of the coupling hole. A coupling hole is bored in an interlayer insulating film (first and second insulating films) to expose the surface of a nickel silicide layer at the bottom portion of the coupling hole. Then, reduction gases including a HF gas and a NH3 gas is supplied to the principal surface of a semiconductor wafer to form a product by a reduction reaction, and remove the natural oxide film on the surface of the nickel silicide layer. At this time, the flow rate ratio (HF/NH3 gas flow rate ratio) between the NF gas and the NH3 gas is adjusted to be more than 1 and not more than 5. Preferably, the temperature of the semiconductor wafer is adjusted to be not more than 30 DEG C. Thereafter, a heating process is performed at 400 DEG C. to the semiconductor wafer to remove the product remaining on the principal surface of the semiconductor wafer, and subsequently form a barrier metal film. |