New CVD precursors capable of depositing copper metal under mixed O-2/Ar atmosphere

[[abstract]]Volatile low-melting Cull metal complexes Cu[OC(CF3)(2)CH2C(Me)=NMe](2) (4) and Cu[OC(CF3)(2)CH2CHMeNHMe](2) (5) were synthesized and characterized by spectroscopic methods. A single-crystal X-ray diffraction study on complex 4 shows the anticipated N2O2 square-planar geometry with the imino alcoholate ligand arranged in the all-trans orientation. In contrast, a highly distorted N2O2 geometry with a dihedral angle of 330 was observed for complex 5, suggesting that the fully saturated amino alcoholate ligand produces a much greater steric congestion around the metal ion. Metal CVD experiments were conducted, showing that both complexes, 4 and 5, are capable of depositing copper metal at temperatures of 275-300 degrees C using an inert argon carrier gas mixed with low concentrations (2-8%) of O-2. The best copper thin film showed a purity of similar to 96 at. % and a resistivity of 2.11 mu Omega cm versus that of the bulk standard (1.7 mu Omega cm), as revealed by XPS and four-point probe analyses, respectively. We speculate that the low concentration Of 02 promotes partial ligand oxidation, thus releasing the reduced copper on the substrate and affording the high-purity copper deposit.[[fileno]]2010302010162[[department]]化學