Zj. Radzimski et al., DIRECTIONAL COPPER DEPOSITION USING DC MAGNETRON SELF-SPUTTERING, Journal of vacuum science & technology. B, Microelectronics and nanometer structures processing, measurement and phenomena, 16(3), 1998, pp. 1102-1106
A directional copper deposition process has been developed that uses a
de magnetron source operating in self-sputtering mode. The process is
performed at 10(-5) Torr range pressure where a ''long throw'' approa
ch can be utilized without discharge enhancement or mechanical collima
tion due to a very long mean free path of sputtered species. Magnetron
sputtering conditions at which the contact hole filling is promoted a
nd substantially enhanced by the self-sputtering process are illustrat
ed and compared to standard sputtering (i.e., short throw, mTorr press
ure) in the presence of argon. The experimental parameters of the new
process have been explored by depositing Cu on patterned Si wafers wit
h trenches and contact holes of various aspect ratios. (C) 1998 Americ
an Vacuum Society.