Copper CVD precursors and processes for advanced metallization: Invited lecture

Abstract

In the last decade, extensive progress has been made towards the design and optimization of Chemical vapor deposition (CVD) precursors for pure copper film growth. Pure copper film is deposited from Cu(I) β-diketonate precursors via a thermally induced disproportionation reaction as shown in Eq. (1): 2 LCu(I)(β − diketonate)→ Cu(O)+ Cu(II)(β − diketonate) 2+2 L Besides the Cupra-select, which is by far the most widely used precursor for the deposition of blanket and selectively deposited copper films, several compounds appear well suited for copper CVD and exist as liquids under ambient conditions. We give here our latest results on the performances of new precursors. Moreover, new processes using CVD and CVD precursors have shown interesting and promising results. Selective metallization of surfaces was achieved using β-diketonate copper (I) complexes in a completely dry two step process. Silica surfaces were derivatized with monofunctional silanes by gas phase silylation. UV-exposure of the halogen or sulfur terminated molecules employing a mask resulted in a controlled pattern of the surface affinity towards the copper complex. The nature of the interaction between the chemically functionalized, patterned surface and the copper precursor is discussed.