Presentation + Paper
13 May 2019 Enhancement of optical properties by incorporating Au quantum dots in CVD WSe2 based photodetector
Author Affiliations +
Abstract
Tungsten diselenide (WSe2) is an interesting two dimensional (2D) transitional metal dichalcogenide (TMDC) with a high quantum yield in photoluminescence (PL), a strong spin-orbit coupling and tunable transport properties. One way to increase photon absorption in WSe2 is to combine WSe2 with other excitonic nanomaterials such as Quantum dots (QDs) from which photogenerated excitons can be transferred onto the TMDCs via non-radiative energy transfer. Such characteristics prove highly effective in the utilization of QDs toward enhancing the optical responsivity of 2D material-based photo-FET devices. In this study, we fabricated WSe2 based photodetector and showed that its photoconduction property was improved by incorporation of Au-QDs. Monolayer WSe2 was synthesized on SiO2/Si by low pressure chemical vapor deposition method at a growth temperature of ~ 850°C. Thereafter, Au-QDs (~15 nm) were drop casted onto WSe2 followed by vacuum annealing. PL spectroscopy showed enhancement in excitonic A-peak intensity by an order of 2-fold in the region where Au QD was incorporated. E-beam lithography was used to fabricate the back gated photo transistor followed by Au/Ti deposition by E-beam evaporation. The device was illuminated with a red laser source (660 nm) to study its optoelectronic properties. The photoresponsivity was found to improve by a factor of ~102 with the incorporation of Au QDs in 1L WSe2. Our results demonstrate the viability of this hybrid structure for commercial photodetector and light harvesting applications.
Conference Presentation
© (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Avra S. Bandyopadhyay and Anupama B. Kaul "Enhancement of optical properties by incorporating Au quantum dots in CVD WSe2 based photodetector", Proc. SPIE 10979, Energy Harvesting and Storage: Materials, Devices, and Applications IX, 109790H (13 May 2019); https://doi.org/10.1117/12.2519131
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Chemical vapor deposition

Photodetectors

Gold

Raman spectroscopy

Quantum dots

Absorption

Optical properties

Back to Top