High-Performance Fully Transparent Ultraviolet Photodetector Fabricated Using GaN-Based Schottky Barrier Photodiode

Transparent electronics is a burgeoning field with exciting potential for next-generation "see-through" devices. The creation of high-performance fully transparent ultraviolet photodetectors (PDs) is essential for enabling wearable and portable applications. In this study, metal-semiconductor-metal (MSM) type Al-doped ZnO (AZO)/GaN/AZO and indium tin oxide (ITO)/GaN/ITO-transparent ultraviolet PDs, are initially designed, utilizing AZO- and ITO-transparent conductive electrodes. In these investigations, it is revealed that AZO and ITO form Ohmic and Schottky contacts, respectively, with GaN. Subsequently, building on these findings, a fully transparent Schottky barrier photodiode (SBPD) is developed for ultraviolet photodetection using AZO/GaN/ITO. The SBPD displays a high responsivity (R) of 1.41 x 103 A W-1, a detectivity (D*) of 6.85 x 1014 Jones, and a photo-to-dark current ratio exceeding 1 x 104 at a - 5 V bias. Furthermore, the SBPD demonstrates an ultrahigh responsivity of 1.18 A W-1 at 0 V bias, indicating its potential as a self-powered device under extreme conditions. In these results, the tremendous potential of the high-performance and fully transparent GaN-based SBPD is demonstrated for environmental monitoring, optical communication, military radar, and other fields. A high-performance, fully transparent, self-powered Schottky barrier diode (SBPD) is developed using GaN epitaxial films with transparent conductive oxide electrodes. The SBPD displays a high responsivity of 1.41 x 103 A/W, a detectivity of 6.85 x 1014 Jones, and a photo-to-dark current ratio exceeding 1 x 104 at a - 5 V bias. Furthermore, the device shows excellent UV-A photoresponse without bias.image (c) 2024 WILEY-VCH GmbH