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arXiv · 1611.03597

Ultrasensitive Self-powered large area planar GaN UV-photodetector using reduced graphene oxide electrodes

Nisha Prakash·Manjri Singh·Gaurav Kumar·Arun Barvat·Kritika Anand·Prabir Pal·Surinder P. Singh·Suraj P. Khanna
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Abstract

A simplistic design of a self-powered UV-photodetector device based on hybrid r-GO/GaN is demonstrated. Under zero bias, the fabricated hybrid photodetector shows a photosensivity of ~ 85% while ohmic contact GaN photodetector with identical device structure exhibits only ~ 5.3% photosensivity at 350 nm illumination (18 microWatt/cm^2). The responsivity and detectivity of the hybrid device were found to be 1.54 mA/W and 1.45x10^10 Jones (cm Hz^(1/2) W^(-1)), respectively at zero bias under 350 nm illumination (18 microWatt/cm^2) with fast response (60 ms), recovery time (267 ms) and excellent repeatability. Power density-dependent responsivity & detectivity revealed ultrasensitive behaviour under low light conditions. The source of observed self-powered effect in hybrid photodetector is attributed to the depletion region formed at the r-GO and GaN quasi-ohmic interface.

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Nisha Prakash, Manjri Singh, Gaurav Kumar, Arun Barvat, Kritika Anand, Prabir Pal, Surinder P. Singh, Suraj P. Khanna. 2016-11-16. Ultrasensitive Self-powered large area planar GaN UV-photodetector using reduced graphene oxide electrodes. https://doi.org/10.1063/1.4971982

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