Chemistry of copper CVD precursors on a Pt(111) surface

摘要

We have investigated the chemistry of Cu(hfac)(sub 2), (hfac)Cu(VTMS), (hfac)Cu(2-butyne), and hfach on a Pt(111) surface. In contrast to what is observed on copper surfaces. Cu(hfac)2 and hfach lead to the formation of distinctly different adsorbed hfac species on Pt(111). This shows the importance of the copper atoms themselves in determining the surface chemistry of copper (beta)-diketonate CVD precursors. The hfac species on Pt(111) are considerably less stable than hfac on copper, suggesting that unimolecular decomposition may lead to impurity incorporation in the interfacial region when copper is deposited onto a more reactive substrate. In situ CVD studies with Cu(I) (beta)-diketonates show that the bimolecular disproportionation reaction leading to copper CVD is favored over unimolecular precursor decomposition at pressures above approximately 10(sup (minus)5) torr.