0000000000086422

AUTHOR

Jaan Aarik

0000-0002-6016-2744

Atomic Layer Deposition of Ruthenium Films from (Ethylcyclopentadienyl)(pyrrolyl)ruthenium and Oxygen

Ru films were grown by atomic layer deposition in the temperature range of 275―350°C using (ethylcyclopentadienyl)(pyrrolyl)ruthenium and air or oxygen as precursors on HF-etched Si, SiO 2 , ZrO 2 , and TiN substrates. Conformal growth was examined on three-dimensional silicon substrates with 20:1 aspect ratio. ZrO 2 promoted the nucleation of Ru most efficiently compared to other substrates, but the films roughened quickly on ZrO 2 with increasing film thickness. The minimum number of cycles required to form continuous and conductive metal layers could be decreased by increasing the length of the oxygen pulse. In order to obtain well-conducting Ru films growth to thicknesses of at least 8―…

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Atomic layer deposition of Ru films from bis(2,5-dimethylpyrrolyl)ruthenium and oxygen

Abstract Ru thin films were grown on hydrogen terminated Si, SiO 2 , Al 2 O 3 , HfO 2 , and TiO 2 surfaces by atomic layer deposition from bis(2,5-dimethylpyrrolyl)ruthenium precursor and oxygen. The 4–20 nm thick films on these surfaces consisted of nanocrystalline hexagonal metallic ruthenium, regardless of the deposition temperature. At the lowest temperatures examined, 250–255 °C, the growth of the Ru films was favored on silicon, compared to the growth on Al 2 O 3 , TiO 2 and HfO 2 . At higher temperatures the nucleation and growth of Ru became enhanced in particular on HfO 2 , compared to the process on silicon. At 320–325 °C, no growth occurred on Si–H and SiO 2 -covered silicon. Res…

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Enhanced flexibility and electron-beam-controlled shape recovery in alumina-coated Au and Ag core–shell nanowires

The proper choice of coating materials and methods in core–shell nanowire (NW) engineering is crucial to assuring improved characteristics or even new functionalities of the resulting composite structures. In this paper, we have reported electron-beam-induced reversible elastic-to-plastic transition in Ag/Al2O3 and Au/Al2O3 NWs prepared by the coating of Ag and Au NWs with Al2O3 by low-temperature atomic layer deposition. The observed phenomenon enabled freezing the bent core–shell NW at any arbitrary curvature below the yield strength of the materials and later restoring its initially straight profile by irradiating the NW with electrons. In addition, we demonstrated that the coating effic…

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