Paper TF-ThP19
Analysis of Surface Species and Film Structure of Thin Films from Atomic Layer Deposition using Surface-Enhanced Raman Spectroscopy

Thursday, November 2, 2017, 6:30 pm, Room Central Hall

In-situ surface-enhanced Raman spectroscopy (SERS) was used to identify dimeric methylalumina surface species during Al₂O₃ atomic layer deposition (ALD) on a silver surface. Vibrational modes associated with the bridging moieties of both trimethylaluminum (TMA) and dimethylaluminum chloride (DMACl) surface species were found during ALD. Density functional theory (DFT) calculations were also performed to locate and identify the expected vibrational modes. DMACl surface species were unable to be measured after multiple ALD cycles as a result of a loss in SERS enhancement and shift in LSPR. Currently, this work is being extended towards other ALD processes (such as TiO₂), as well as expanded to identify other characteristics of the thin films produced using adsorbate vibrational spectroscopy. This work highlights how in-situ optical spectroscopy by SERS and LSPR scattering are useful for probing the identity and structure of the surface species involved in ALD, as well as the structure of the resulting film.