Atypical behavior of intrinsic defects and promising dopants in two-dimensional WS2

Singh, A and Singh, AK (2021) Atypical behavior of intrinsic defects and promising dopants in two-dimensional WS2. In: Physical Review Materials, 5 (8).

PDF phy_rev_mat_05-08_2021.pdf - Published Version Restricted to Registered users only Download (2MB) | Request a copy

Abstract

The 2D-WS2 is an emerging material for next-generation electronic and optoelectronic devices. These applications are very sensitive and can be adversely affected by defects incorporated during the sample growth. Using hybrid density functional approach, we carried out a comprehensive study on intrinsic and extrinsic defects in 2D-WS2. All the intrinsic defects and their complexes are found to be deep and self-compensating. S vacancy (VS), which has been previously attributed as the source of n-type conductivity, turns out to be an electron trap center. We found that VS gives rise to a suboptical gap, which can be the source of single-photon emitters. Interestingly, hydrogen interstitial (Hi) makes multicenter bond and acts as a shallow donor. In addition, H as adatom (H-ad) also provides shallow donor levels and is the cause of unintentional n-type doping. Among the extrinsic defects, halogens and transition metals are found to be promising dopants. While halogens at the S site act as shallow donors, Nb at the W site provides a reasonable shallow acceptor level with low formation energy. © 2021 American Physical Society.

Item Type:	Journal Article
Publication:	Physical Review Materials
Publisher:	American Physical Society
Additional Information:	The copyright for this article belongs to American Physical Society
Keywords:	Optoelectronic devices; Particle beams; Transition metals, Electron trap center; Emerging materials; Formation energies; Hybrid density functional; Intrinsic defects; N-type conductivity; Self-compensating; Single photon emitters, Tungsten compounds
Department/Centre:	Division of Chemical Sciences > Materials Research Centre
Date Deposited:	16 Nov 2021 11:02
Last Modified:	16 Nov 2021 11:02
URI:	http://eprints.iisc.ac.in/id/eprint/69827

Actions (login required)

View Item