ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Asymmetrically Encapsulated Vertical ITO/MoS2/Cu2O Photodetector with Ultrahigh Sensitivity

Kallatt, Sangeeth and Nair, Smitha and Majumdar, Kausik (2018) Asymmetrically Encapsulated Vertical ITO/MoS2/Cu2O Photodetector with Ultrahigh Sensitivity. In: SMALL, 14 (3).

[img] PDF
smll201702066.pdf - Published Version
Restricted to Registered users only

Download (1MB) | Request a copy
Official URL: http://dx.doi.org/10.1002/smll.201702066

Abstract

Strong light absorption, coupled with moderate carrier transport properties, makes 2D layered transition metal dichalcogenide semiconductors promising candidates for low intensity photodetection applications. However, the performance of these devices is severely bottlenecked by slow response with persistent photocurrent due to long lived charge trapping, and nonreliable characteristics due to undesirable ambience and substrate effects. Here ultrahigh specific detectivity (D-star) of 3.2 x 10(14) Jones and responsivity (R) of 5.77 x 10(4) A W-1 are demonstrated at an optical power density (P-op) of 0.26 W m(-2) and external bias (V-ext) of -0.5 V in an indium tin oxide/MoS2/copper oxide/Au vertical multi-heterojunction photodetector exhibiting small carrier transit time. The active MoS2 layer being encapsulated by carrier collection layers allows us to achieve repeatable characteristics over large number of cycles with negligible trap assisted persistent photocurrent. A large D-star > 10(14) Jones at zero external bias is also achieved due to the built-in field of the asymmetric photodetector. Benchmarking the performance against existing reports in literature shows a viable pathway for achieving reliable and highly sensitive photodetectors for ultralow intensity photodetection applications.

Item Type: Journal Article
Publication: SMALL
Publisher: 10.1002/smll.201702066
Additional Information: Copy right for this article belongs to the WILEY-V C H VERLAG GMBH, POSTFACH 101161, 69451 WEINHEIM, GERMANY
Department/Centre: Division of Electrical Sciences > Electrical Communication Engineering
Date Deposited: 02 Mar 2018 15:07
Last Modified: 02 Mar 2018 15:07
URI: http://eprints.iisc.ac.in/id/eprint/58877

Actions (login required)

View Item View Item