Kemelbay, AidarTikhonov, AlexanderAloni, ShaulKuykendall, Tevye R.2019-12-122019-12-122019-08Kemelbay, Tikhonov, Aloni, & Kuykendall. (2019). Conformal High-K Dielectric Coating of Suspended Single-Walled Carbon Nanotubes by Atomic Layer Deposition. Nanomaterials, 9(8), 1085. https://doi.org/10.3390/nano908108510.3390/nano9081085http://nur.nu.edu.kz/handle/123456789/4436https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6723932/As one of the highest mobility semiconductor materials, carbon nanotubes (CNTs) have been extensively studied for use in field effect transistors (FETs). To fabricate surround-gate FETs— which offer the best switching performance—deposition of conformal, weakly-interacting dielectric layers is necessary. This is challenging due to the chemically inert surface of CNTs and a lack of nucleation sites—especially for defect-free CNTs. As a result, a technique that enables integration of uniform high-k dielectrics, while preserving the CNT’s exceptional properties is required. In this work, we show a method that enables conformal atomic layer deposition (ALD) of high-k dielectrics on defect-free CNTs. By depositing a thin Ti metal film, followed by oxidation to TiO2 under ambient conditions, a nucleation layer is formed for subsequent ALD deposition of Al2O3. The technique is easy to implement and is VLSI-compatible. We show that the ALD coatings are uniform, continuous and conformal, and Raman spectroscopy reveals that the technique does not induce defects in the CNT. The resulting bilayer TiO2/Al2O3 thin-film shows an improved dielectric constant of 21.7 and an equivalent oxide thickness of 2.7 nm. The electrical properties of back-gated and top-gated devices fabricated using this method are presented.enAttribution-NonCommercial-ShareAlike 3.0 United Statescarbon nanotubeatomic layer depositiondielectricTiO2nucleation layerArticle