Area-Selective Atomic Layer Deposition of Ruthenium on SiO 2 /W Patterns Using Silicon-Based Inhibitors

Area-selective atomic layer deposition (AS-ALD) has garnered considerable interest over the past decade due to its potential to enable bottom-up fabrication of nanostructures with atomic-scale precision, eliminating the need for complex multiple patterning and lithographic processes that often introduce alignment challenges. Selective deposition is achieved by facilitating nucleation and growth on the targeted growth area (GA) while chemically passivating the non-growth area (NGA) to inhibit film formation. This study explores the inhibition performance of two small molecular inhibitors (SMIs) dimethylamino-trimethylsilane (DMATMS) and bis(dimethylamino)dimethylsilane (BDMADMS) were evaluated, for area-selective ALD (AS-ALD) of Ru on the surface consisted with SiO 2 and W using a carbonyl-based Ru precursor and O 2 as an oxidant at 250 °C. BDMADMS, applied via spin-coating and baking, enabled selective Ru deposition on W surfaces while effectively suppressing nucleation and deposition on SiO 2 surfaces for up to 500 ALD cycles, in contrast, DMATMS dip provided short-term inhibition, but Ru was later deposited on SiO 2 . We found that BDMADMS forms a stable inhibitor layer on SiO 2 , exhibiting strong chemical stability and effectively protecting the surface from oxidative environments, thereby preventing Ru deposition, while DMATMS forms a less stable inhibitor layer on SiO 2 , which degrades under oxidative conditions, leading to the loss of surface passivation and subsequent Ru deposition. Finally, optimized AS-ALD of Ru was achieved on three-dimensional SiO 2 and W patterned surface using BDMADMS as a SMI, where Ru selectively deposited only on the W regions, demonstrating precise control over nucleation and deposition, its promise for advanced integration strategies.