The research line proposed in this stage proposal is focused on the area-selective deposition (ASD) concept, where the growth of the desired dielectric material is confined to a pre-patterned area while inhibited on the remaining surface. On one hand, Atomic Layer Deposition (ALD) is a method to deposit thin films by a self-limited surface adsorption of gas-phase precursors and surface reactions between adsorbed precursors and reactants molecules, allowing a tight control of the deposited material thickness and quality at the atomic scale. On the other hand, the deposition of monomolecular organic films (such as self-assembled monolayers, SAMs) or functionalized polymeric layers is a simple and versatile method to control surface design and selectivity. The SAM or polymeric films act as ALD inhibition layers that can prevent deposition in certain surface areas, enabling area selective deposition. Two SAM deposition methods will be explored, i.e. from organic solvents (dip-coating and spin-coating) or from vapour phase (in a CVD-like reactor). The density and thermo-chemical stability of the organic inhibition layer is of paramount importance in order to withstand the ALD conditions, such as thermal budget, precursor type and dose, gas flow and pulse/purge duration. Two main mechanisms of selectivity loss might be attributed to unwanted interaction mechanisms between SAMs and ALD: i) channeling of the ALD precursors through the SAM molecular units (if not dense enough), ii) modification of the SAM terminal group exposed to the surface. On polymeric films, the loss of selectivity might be attributed to surface energy/polarity modification. On the other side, the ALD deposition on the target areas might be "poisoned" by unwanted organic residues. The advanced characterization of the nano-scale organic and inorganic films both on blanket areas and in confined dimensions will be part of the generated learning and will benefit of the extensive expertise already present in Imec. Defect generation mechanism and quantification will be tackled. The final goals of this project are i) to generate the scientific understanding needed to design area selective deposition approaches for patterning applications in nano-electronic device fabrication based on both SAM/polymeric films and ALD; ii) to transfer the learning from blanket surfaces to relevant nano-scale patterns taking into account pattern profile and transition regions between growth and no-growth areas.
In our research program on area selective deposition we leverage Imec's 300mm pilot line and advanced node technologies to gain access to materials and patterned structures with dimensions in the sub-10 nm regime in order to enable industrially relevant innovation.
Required background: Chemistry, Materials, Nanotechnology
Type of work: 10% literature study, 90% experimental work
Daily advisor: Silvia Armini
Type of project: Thesis, Combination of internship and thesis
Required degree: Master of Science, Master of Engineering Science
Required background: Chemistry/Chemical Engineering, Materials Engineering, Nanoscience & Nanotechnology
Supervising scientist(s): For further information or for application, please contact: Silvia Armini (Silvia.Armini@imec.be)
Only for self-supporting students.