| There are many challenges to extending future uses of copper in integrated circuitry. Research continues to concentrate on depositing conformal, uniform, and continuous copper films into high aspect ratio features. There is currently no known practical process to achieve high quality copper thin films by atomic layer deposition. In this study, plasma-assisted atomic layer deposition of copper, using CuII(tmhd)2 and an inductively coupled hydrogen plasma, is shown on metallic and dielectric substrates. Nonselective deposition was achieved on SiO2, Au, and TaNX in the temperature range between 60°C and 400°C. Deposition was self-limiting from ∼90°C to 250°C. Saturation was observed for each half reaction and for purging times.; A novel method to demonstrate self-limiting behavior of the first half reaction was developed. This consisted of pulsing the precursor once over long times (on either SiO2 or Pt substrates) followed by observation of the resulting growth by Rutherford backscattering.; Thermal atomic layer deposition via CuII(tmhd)2 and H2 was attempted and was very slow within the self-limiting temperature range. These experiments were undertaken on all of the metallic and dielectric surfaces studied here including a plasma-assisted atomic layer deposited copper seed layers.; Properties of the films deposited in this study were analyzed, using transmission electron microscopy, atomic force microscopy and Scotch tape peal tests. In addition, Rutherford backscattering using a carbon substrate was shown to increase the light element minimum detection limits by two orders of magnitude as compared to Rutherford backscattering on silicon wafers.; A low k chemical vapor deposited poly(p-xylylene) polymer sealant was deposited at room temperature onto the porous ultra-low k dielectric methyl silsesquioxane. Experiments show that poly(p-xylylene) prevents precursor penetration during subsequent metal organic chemical vapor deposition. While the poly(p-xylylene) penetrates slightly into the methyl silsesquioxane, it does not appreciably increase surface roughness or film dielectric constant. This result is important for the potential future use of atomic layer deposition in metallization of porous dielectrics. |
