Ultraviolet Photodetection Properties of ZnO/Si Heterojunction Diodes Fabricated by ALD Technique Without Using a Buffer Layer

Abstract

Abstract-The fabrication and characterization of a Si/ZnO thin film heterojunction ultraviolet photodiode has been presented in this paper. ZnO thin film of ~100 nm thick was deposited on <100> Silicon (Si) wafer by atomic layer deposition (ALD) technique. The Photoluminescence spectroscopy confirms that as-deposited ZnO thin film has excellent visible-blind UV response with almost no defects in the visible region. The room temperature current-voltage characteristics of the n-ZnO thin film/p-Si photodiodes are measured under an UV illumination of 650 µW at 365 nm in the applied voltage range of ±2V. The current-voltage characteristics demonstrate an excellent UV photoresponse of the device in its reverse bias operation with a contrast ratio of ~ 1115 and responsivity of ~0.075 A/W at 2 V reverse bias voltage.

A Photodetector Based on p-Si/n-ZnO Nanotube Heterojunctions with High Ultraviolet Responsivity

“…However, under illumination, electrons and holes generated in the depletion region of the p-Si/n-ZnO NT heterojunctions drift in opposite directions in the presence of an electric field operating under a reverse bias, leading to the collection of more photocurrent than dark current and the disappearance of the rectification characteristics of the device. Such behavior has been observed in p-n PDs. ,,,,, A reverse bias is thus advantageous for PDs because it increases the depletion width, while decreasing the photoinduced carrier transit time and the carrier loss . Under a forward bias, a photoresponse to UV light is also possible.…”

“…Such behavior has been observed in p-n PDs. 19,20,22,40,53,54 A reverse bias is thus advantageous for PDs because it increases the depletion width, while decreasing the photoinduced carrier transit time and the carrier loss. 19 Under a forward bias, a photoresponse to UV light is also possible.…”

Tuning Carrier Tunneling in van der Waals Heterostructures for Ultrahigh Detectivity

“…The maximum detectivity of 2.6 × 10 13 Jones, 100–1000 times higher than that of other MoS 2 -based devices, ,, which is achieved with the highest I ph / I dark ratio and relatively high photoresponsivity at a h-BN thickness of 7 nm. Moreover, the conventional ZnO/Si photodetector shows a detectivity of 6.44 × 10 11 Jones, which is 2 orders of magnitude smaller than our device (Table S1).…”

High performance GZO/p-Si heterojunction diodes fabricated by reactive co-sputtering of Zn and GaAs through the control of GZO layer thickness

“…26 The n-ZnO/p-Si heterojunction diodes are specially attractive, owing to the availability and quality of crystalline silicon, as well as the possibility of hybrid integration of ZnO based devices with high density silicon technology. As a result, fabrication of n-ZnO/p-Si heterojunction diodes have been attempted by various deposition processes, such as thermal evaporation, 27,28 chemical bath deposition 29 magnetron sputtering 30,31 pulsed laser deposition 32,33 and chemical vapour deposition, 34 albeit with moderate performance, resulting in diode ideality factors, usually in the range of 2–10. 35–37 …”