Publications

Chemistry of Titanium Deposition Precursors for Area-Selective Deposition of Functionalized Silicon [Posters]

Parker, Tyler P.; Silva-Quinones, Dhamelyn0x S.; Wang, George T.; Teplyakov, Andrew V.

Area-selective atomic layer deposition (AS-ALD) is an appealing bottom-up fabrication technique that can produce atomic-scale device features, overcoming challenges in current industrial techniques such as edge alignment errors. TiCI₄ is a common thermal ALD precursor for Ti0₂ thin films, which are appealing candidates for DRAM capacitors due to their excellent dielectric constants. Hydrogen and chlorine termination passivate the Si surface, allowing for selective deposition of TiCI₄ onto HO-terminated areas. However, selectivity loss occurs after several ALD cycles. Ti oxide nucleates onto surface defects on Cl- and H-Si resists. Previously, the use of H-Si as an ALD resist has been studied extensively, but less work has focused on chemical forces driving nucleation, especially for Cl-Si. Here, formation of defect nuclei was investigated with selectivity loss during Ti0₂ ALD with TiCI₄ and water on the (100) and (111) crystal surfaces of hydrogenated, chlorinated, and oxidized Si.