Van der Waals epitaxial growth and optoelectronics of large-scale WSe<sub>2</sub>/SnS<sub>2</sub> vertical bilayer p-n junctions.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29203864.
- Also identified by DOI 10.1038/s41467-017-02093-z and PMC identifier 5715014.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
High-quality two-dimensional atomic layered p-n heterostructures are essential for high-performance integrated optoelectronics. The studies to date have been largely limited to exfoliated and restacked flakes, and the controlled growth of such heterostructures remains a significant challenge. Here we report the direct van der Waals epitaxial growth of large-scale WSe<sub>2</sub>/SnS<sub>2</sub> vertical bilayer p-n junctions on SiO<sub>2</sub>/Si substrates, with the lateral sizes reaching up to millimeter scale. Multi-electrode field-effect transistors have been integrated on a single heterostructure bilayer. Electrical transport measurements indicate that the field-effect transistors of the junction show an ultra-low off-state leakage current of 10<sup>-14</sup> A and a highest on-off ratio of up to 10<sup>7</sup>. Optoelectronic characterizations show prominent photoresponse, with a fast response time of 500 μs, faster than all the directly grown vertical 2D heterostructures. The direct growth of high-quality van der Waals junctions marks an important step toward high-performance integrated optoelectronic devices and systems.