| 초록 |
We synthesized a Cu-Ti alloy by employing alternating atomic layer deposition (ALD) surface reactions using Cu and Ti precursors, respectively. By alternating between these two ALD surface chemistries, we fabricated ALD Cu-Ti alloy. Cu was deposited using (Hexafloroaceticaceto)(Tertiary-buteno)copper (hfac(Cu)DMB) as a precursor and H2 plasma, while Ti was deposited using tetrakis(dimethylamino)titanium (TDMAT) as the precursor and H2 plasma. The ti atomic percent in the Cu-Al alloy films varied from 0 at.% to 15.2 at.%. Transmission electron microscopy revealed that a uniform Ti-based interlayer self-formed at the interface after annealing. To evaluate the barrier properties of the Ti-based interlayer and adhesion between the Cu-Ti alloy film and SiO2 dielectric, thermal stability and peel-off adhesion tests were performed, respectively. The Ti-based interlayer showed similar thermal stability and adhesion to the reference Mn-based interlayer. Our results indicate that Cu-Ti alloys formed by alternating ALD are suitable seed layer materials for Cu interconnects.Key words: Cu-Ti alloy, atomic layer deposition, self-forming barrier, Cu diffusion barrier |
