EXPERIMENTAL MODIFICATIONS TO AN ESTABLISHED ATOMIC LAYER DEPOSITION PROCESS TARGETING AREA-SELECTIVITY
Access to this document is restricted. Some items have been embargoed at the request of the author, but will be made publicly available after the "No Access Until" date.
During the embargo period, you may request access to the item by clicking the link to the restricted file(s) and completing the request form. If we have contact information for a Cornell author, we will contact the author and request permission to provide access. If we do not have contact information for a Cornell author, or the author denies or does not respond to our inquiry, we will not be able to provide access. For more information, review our policies for restricted content.
Atomic layer deposition (ALD) is a process capable of depositing atomically thin and conformal films over intricate 3D substrates. To further integrate ALD processes in nanomanufacturing lines, area-selective ALD (AS-ALD) processes are being investigated in which deposition is controlled by the chemical composition of the starting substrates. The results detailed herein utilized a custom-built reactor equipped with a quartz crystal microbalance (QCM) to monitor depositions in real time. Ex situ characterization was performed on select wafer coupons using atomic force microscopy (AFM), water contact angle (WCA), and X-ray photoelectron spectroscopy (XPS). One of the most well-researched ALD processes is using trimethylaluminum (TMA) as the precursor and water as the co-reactant to deposit aluminum oxide. In the first part of this thesis, a series of alkyl alcohols are used as co-reactants in place of water to determine the rationale underpinning the occurrence of steady-state deposition. The second part varies the precursor from TMA to an alternative Al precursor (NcAP). Building upon a previously developed NcAP
H2O ALD process, films were deposited using water and tert-butanol as co-reactants and subsequently compared against TMA-grown films to determine growth rate, roughness, density, and stoichiometry. Finally, two process chemistries (TMA
H2O and NcAP
H2O) were tested for AS-ALD utilizing either liquid- or vapor-phase blocking molecules to chemically passivate the non-growth surface. From preliminary results, the bulkier ligands on NcAP led to a prolonged nucleation delay on the non-growth surface.