Two-Dimensional Heterostructure Based Electronic and Optoeletronic Devices

Lead Research Organisation: University of Bath
Department Name: Physics

Abstract

This project will involve the development of the process for in-situ fabrication of large area 2D material
heterostructures to realise optical and electronic devices. The choice of 2D material system can be either hBN/WSe2/
hBN or 2D MoS2/WSe2 pn junctions (or similar functional combinations including graphene and conventional 3D
dielectric layers). The aims of this project would be to characterize the optical and electronic properties of such
stacks and investigate the interfaces between these layers.
Specific objectives include: 1) Development of a CVD/ALD process for the chosen 2D heterostructure systems. 2)
Characterization of device mobility including PL efficiency, Raman (and other) spectroscopy of strain and interlayer
modes, microscopy of domain sizes etc. of individual semiconducting materials and the effects on mobility due to the
formation of heterostructures. These data will be used as feedback to improve deposition processes. 3) Nano-
ARPES of the electronic structure of heterostructures. 4) Fabrication of pn-junction-based photodetectors and
tunnelling diode/transistor devices. 5) Comprehensive device characterization data for the chosen systems and
devices, including scanning photocurrent microscopy and I-V curves. 6) Exploration of novel heterostructure-based
valleytronic device concepts.

Publications

10 25 50

Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/R51245X/1 01/10/2017 30/09/2021
1944673 Studentship EP/R51245X/1 18/09/2017 31/12/2021 William Robert Campbell
 
Description I have spent a year creating a recipe to grow high quality monolayers of tungsten disulfide (WS2) on sapphire and SiO2 substrates. We have managed to growth these thin films using a tungsten precursor (WCl6) that is different to the precursor most widely reported in literature. We have characterised our WS2 using Raman and Photoluminescence spectroscopy, and verified film thickness through atomic force microscopy. A further key result is that a post growth sulfur anneal drastically increases the optical quality of the ws2 thin films.
Exploitation Route This work was a collaborative effort alongside Oxford Instruments Plasma Technology. They are already using my results to advertise their CVD tool and its capabilities.
Sectors Aerospace, Defence and Marine,Digital/Communication/Information Technologies (including Software),Electronics,Energy,Environment

 
Description Oxford Instruments Plasma Technology 
Organisation Oxford Instruments Plasma Technology
Country United Kingdom 
Sector Private 
PI Contribution I used the facilities at OIPT to grow my materials. I used their chemical vapour deposition reactor.
Collaborator Contribution I was provided with industry expertise and a dedicated team to support my work.
Impact Current paper in writing Data used for company advertising
Start Year 2017