Field-Effect Device Using Quasi-Two-Dimensional Electron Gas in Mass-Producible Atomic-Layer-Deposited Al<sub>2</sub>O<sub>3</sub>/TiO<sub>2</sub> Ultrathin (<10 nm) Film Heterostructures.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30204410.
- Also identified by DOI 10.1021/acsnano.8b05891.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
We report the field-effect transistors using quasi-two-dimensional electron gas generated at an ultrathin (∼10 nm) Al<sub>2</sub>O<sub>3</sub>/TiO<sub>2</sub> heterostructure interface grown via atomic layer deposition (ALD) on a SiO<sub>2</sub>/Si substrate without using a single crystal substrate. The 2DEG at the Al<sub>2</sub>O<sub>3</sub>/TiO<sub>2</sub> interface originates from oxygen vacancies generated at the surface of the TiO<sub>2</sub> bottom layer during ALD of the Al<sub>2</sub>O<sub>3</sub> overlayer. High-density electrons (∼10<sup>14</sup> cm<sup>-2</sup>) are confined within a ∼2.2 nm distance from the Al<sub>2</sub>O<sub>3</sub>/TiO<sub>2</sub> interface, resulting in a high on-current of ∼12 μA/μm. The ultrathin TiO<sub>2</sub> bottom layer is easy to fully deplete, allowing an extremely low off-current, a high on/off current ratio over 10<sup>8</sup>, and a low subthreshold swing of ∼100 mV/decade. Via the implementation of ALD, a mature thin-film process can facilitate mass production as well as three-dimensional integration of the devices.