Growth of highly conformal ruthenium-oxide thin films with enhanced nucleation by atomic layer deposition

摘要: Abstract Highly conformal and conductive RuO2 thin films were deposited without nucleation delay using atomic layer deposition (ALD) by zero-valent metallorganic precursor, (ethylbenzyl)(1,3-cyclohexadienyl)Ru(0) (EBCHDRu, C14H18Ru) molecular oxygen (O2) as a precursor reactant, respectively. could be successfully prepared controlling the process parameters, such reactant flow rate, pulsing time, temperature. X-ray diffractometry, photoelectron spectroscopy, secondary ion mass spectrometry analysis revealed that formation of phase became favorable with increasing both rate time decreasing With optimized conditions, film at 225 °C had tetragonal structure exhibited excellent properties low resistivity 118 μΩ-cm, high density 6.85 g/cm3 close to bulk value, negligible roughness 0.33 nm. The growth ALD-RuO2 was 0.186 nm/cycle on SiO2 substrate number incubation cycles 2. showed step coverage ∼100% onto 25-nm-width trench structures an aspect ratio 4.5. highly stable up annealing 700 °C in O2 N2 ambient. Finally, evaluated bottom electrode metal–insulator-metal capacitor high-k (dielectric constant) ALD-TiO2 dielectric. dielectric constant confirmed ∼68. This extremely attributed rutile-structured TiO2 top electrode, evidenced high-resolution transmission electron microscopy analysis.