Direct Growth of Lateral ZnO Nanorod UV Photodetectors with Schottky Contact by a Single-Step Hydrothermal Reaction

Abstract

Lateral zinc oxide (ZnO) nanorod metal-semiconductor-metal ultraviolet detectors with different metal contact were fabricated on glass substrate by a single-step hydrothermal reaction. With the combined effect from a ZnO seed layer and an inactive layer for nanorod growth, ZnO nanorods could grow laterally and aligned between the interdigitated electrodes. When the growth process is terminated, the integration of ZnO nanorods into a function device can be achieved in the meantime. The structure can be modeled as being composed of two same Schottky barriers connected back to back, in series with a resistance of R. The devices are visible-blind and have great response even in mid ultraviolet region. The photodetectors with Ni electrode show better performance both in the aspect of photocurrent and response time, owing to the larger Schottky barrier at the Ni/ZnO interface. By surface coating with polymethyl methacrylate, the response has been further improved. Our approach provides a simple and effective way to fabricate high performance ultraviolet detectors.

Enhanced Ga2O3/SiC ultraviolet photodetector with graphene top electrodes

“…At a reverse bias of À5 V, the photocurrent increases instantaneously to approximately 24.12 mA when illumination is on and reduces to 15.99 mA when illumination is off. The response (rising) edges and the recovery (fall) edges usually consist of two components with a fast response component and a slow-response component [8,21]. For a more detailed comparison of the response time of the b-Ga 2 O 3 /4HeSiC heterojunction, the quantitative analysis of the process of the current rise and decay process involves the fitting of the photoresponse curve with a bi-exponential relaxation equation of the following type [8,21].…”

Self-powered hybrid humidity sensor and dual-band UV photodetector fabricated on back-contact photovoltaic cell

“…To discuss the response time of the PDs, the curve in Fig. 7 was fitted by the following equation [22,23]:…”

Chemical bath deposited ZnO thin film based UV photoconductive detector

“…ZnO has a low material cost and low deposition temperature [14]. It is n-type semiconductor material with wide direct band gap of 3.3 eV and large exciton binding energy of 60 meV, which makes it a suitable candidate for fabrication of UV photodetector [15] as well as UV light emitting diodes [16]. Another main advantage of ZnO is, there is various synthesis method and diverse processing technologies to fabricate ZnO based UV photodetector.…”