THE PROCESSING WINDOWS FOR SELECTIVE COPPER CHEMICAL-VAPOR-DEPOSITIONFROM CU(HEXAFLUOROACETYLACETONATE)TRIMETHYLVINYLSILANE

To identify the processing tolerance for the selective Cu chemical vap or deposition (Cu CVD) the processing windows were constructed with re spect to deposition pressure and substrate temperature over thermally grown SiO2 vs. various conducting substrates of W, CoSi2, TiN, TiW, an d Al. It is found that the width of selective deposition window decrea ses as the deposition pressure is increased, and no selective Cu depos ition can be obtained as the deposition pressure exceeds 120 mTorr. Th e lowest temperatures for Cu CVD on various SiO2 substrates including thermally grown, BPSG, TEOS, and PECVD SiO2 were determined so that pr ocessing windows for selective Cu deposition on Variously patterned wa fers can be constructed. The selective Cu deposition was also conducte d on patterned substrates with submicrometer feature sizes using the P ECVD SiO, as the interlayer dielectric. The nucleation of Cu on the Si O2 surface obviously acts as the major limitation for achieving select ive Cu CVD. We postulate that the Cu containing adspecies, Cu(hfac), o n the insulating SiO2 surface may combine by surface diffusion, and th ese assembled adspecies then disproportionate by exchanging electrons with each other rather than transferring electrons through the substra te.