| 초록 |
Cu thin films were deposited on the sputter-deposited Ta/Si substrate using cycles of alternate supply of Cu(I) precursor pulse and argon purge gas. We used (hfac)Cu(DMB) and (hfac)Cu(VTMS) for Cu(I) precursor. 200~1000 cycles were performed to deposit films at growth temperatures as low as 70℃ and 80℃ for (hfac)Cu(DMB) and (hfac)Cu(VTMS) respectively. The growth rate was ~0.75Å/cycle for (hfac)Cu(DMB) and ~1.9Å/cycle for (hfac)Cu(VTMS). We compared properties of Cu films deposited by pulsed-MOCVD with those by MOCVD. The surface morphology, roughness and crystallinity were examined using SEM, AFM and XRD. Pulsed-MOCVD showed better film properties of continuity, uniformity, smoothness and preferential Cu(111) crystallographic orientation than those of MOCVD. In the pulsed-MOCVD film, the impurities of C and F atom were below detection limits and only O atom was detected lower than 3 average atom % which was a quarter of that in the MOCVD film. Finally we made an attempt to deposit Cu seed layer on 0.25μm width trench structure with an aspect ratio of 10 by pulsed-MOCVD. After performing 650 cycles, a highly conformal Cu seed layer with 75nm thickness was obtained. |
