Self-powered photosensing characteristics of amorphous carbon/silicon heterostructures. Issue 46 (21st April 2016)

• Record Type: Journal Article
• Authors: Hao, L. Z.; Liu, Y. J.; Gao, W.; Han, Z. D.; Xu, Z. J.; Liu, Y. M.; Zhu, J.
• Is Part Of: RSC advances. Volume 6:Issue 46(2016)
• Page Start: 40192
• Page End: 40198
• Publication Date: 2016-04-21
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra04360g
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : A self-powered photodetector based on a a-C/Si heterojunction is fabricated. Under zero voltage, the device shows excellent photosensing characteristics with a high stability, a high detectivity and responsitivity, as well as a fast response speed. Abstract : Amorphous carbon (a-C) thin films are deposited on p-type silicon (Si) substrates using magnetron sputtering technique and the photodetector devices based on the a-C/Si heterostructures are fabricated. The photosensing characteristics of the devices are investigated. Under light irradiation, the fabricated a-C/Si device exhibits obvious photovoltaic characteristics. This enables its application as a self-powered photodetector operated at zero bias voltage. The obtained results show that the device is highly sensitive to broadband wavelength from the ultraviolet to near-infrared light, showing a high detectivity of ∼2.9 × 10 13 cm Hz 1/2 W −1, as well as a high responsitivity of ∼292.5 mA W −1, and a fast response speed of ∼8.3 μs. The mechanisms to the self-powered photosensing characteristics are clarified by the determination of the energy-band alignment near the interface of the a-C/Si heterostructures.