method of the invention includes a technique for deposition of a titanium based thin film as a barrier layer prior to copper interconnect formation wherein tetrakis methylethylamino titanium tmeat is mixed with octane 95 by volume to boost the resultant precursor 39 s efficiency and to reduce the fabrication cost without sacrificing the barrier properties required for copper interconnects the method of the invention differs from the prior art in that 1 a single source for tin deposition is the only source nh 3 is not required as in the known prior art for tin deposition the resulting film properties are superior to tin films deposited from pvd or non treated cvd 2 the tmeat is mixed with octane 95 by volume which is a new way to use tmeat in tin deposition 3 the precursor mixture is much cheaper and does not clog the showerhead in the deposition chamber as does prior art precursors 4 the precursor of the method of the invention has better wetting character with cvd copper and also has better adhesion characteristics and 5 the precursor provides better contact resistance after sih 4 treatment as mentioned above thin tin tisin barrier films formed using a tmeat precursor have.