Ultra-low-power photodetector based on a high-photoresponse, plasmonic-effect-induced gateless quasi-freestanding graphene device

Authors

Khadka I.B., Alluri N.R., Alsardia M.M., Joseph Raj N.P.M., Prasanna A.P.S., Ul Haq B., Kim S.J., Kim S.H.

Reference

Applied Surface Science, vol. 610, art. no. 155275, 2023

Description

Large-area metal-graphene-metal UV–Visible photodetectors fabricated on quasifreestanding graphene (QFSG)/vicinal SiC (8° off-axis) wafers are applicable to future low-power consumption systems. They demonstrate effective photoresponse under 365 nm (UV) and 405 nm (Visible) light irradiation upon the application of a built-in electric field (self-biased) and ultra-low bias (−10 mV). Photocurrent gain and responsivity under UV–Visible light are more significant on QFSG/vicinal SiC than on epitaxial graphene (EG)/SiC(0 0 0 1) because of the freestanding nature of the topmost layer, absence of a buffer layer, and primary carrier scattering/trapping centers. Further, they are tuned by localized surface plasmon resonance using gold nanoparticles (AuNPs). In the self-power mode and low-bias mode in QFSG/vicinal SiC, the photocurrent is enhanced by 9-fold and 120-fold, respectively, compared to the photocurrent in EG/SiC(0 0 0 1). The responsivity of QFSG/vicinal SiC after AuNP treatment is ≈1.65 mA/W (at zero bias) and ≈20 mA/W (at −10 mV) under 365 nm light illumination (intensity = 18 mW/cm−2), significantly higher than that of EG/SiC (0 0 0 1). This device shows a similar trend of photoresponse under 405 nm light illumination. These results confirm that this QFSG/vicinal SiC combined with AuNPs possesses potential for application in UV–Visible detection with minimum power consumption.

Link

doi:10.1016/j.apsusc.2022.155275