Integrated Flexible Ga₂O₃ Deep UV Photodetectors Powered by Environmental Electromagnetic Radiation Energy

Abstract

This work reports an integrated flexible deep ultraviolet (UV) photodetection system hosting an amorphous Ga2O3 (a‐Ga2O3) photodetector (PD) and an energy harvesting component including a receiving electrode and a full‐wave rectifier. An alternating signal is induced by the coupling of human body with environmental electromagnetic radiation through human hand's contact with the receiving electrode. The signal is subsequently converted into direct current (DC) by the rectifier which is composed of four thin‐film diodes with high rectification ratio (≈106) and fast response time (rising time ≈240 µs and falling time ≈680 µs). Driven by the DC output, the a‐Ga2O3 PD achieves a photoresponsivity of 0.10 A W−1 and a detectivity of 2.24 × 1011 Jones under 254 nm UV illumination. The integrated flexible a‐Ga2O3 UV PD manifests a repeatable and pleasurable response behavior with a bending radius of 15 mm, providing a new paradigm for utilizing the environmental energy as the power source in wearable electronics.

Ultrahigh Gain Solar Blind Avalanche Photodetector Using an Amorphous Ga2O3-Based Heterojunction

“… − Photomultiplier tubes (PMTs) represent a type of sensitive UV PDs capable of converting weak UV light into electronic signal resorting to ultrahigh internal gain (>10 6 ). − However, PMTs are expensive to make as well as rather bulky and fragile, impeding the miniaturization of the devices that use them. The recent development of synthesizing wide bandgap semiconductors including AlN, AlGaN, MgZnO, and Ga 2 O 3 has propelled these emerging semiconductors to the forefront of solar-blind PDs research and development. − All-solid-state PDs incorporating such active semiconductors can be reliably fabricated, and extend the applicability of detection pixel down to the nanoscale. − Among them, Ga 2 O 3 has been recognized as an excellent candidate promoting solar-blind PDs owing to the suitable bandgap (4.5–4.9 eV) . Furthermore, its chemical and thermal stability, radiation hardness, high breakdown electric field (∼8 MV/cm), and low cost have positioned it as the workhorse material for solar-blind UV PDs. , So far, a wide variety of Ga 2 O 3 -based PDs with different structures have been developed, including photoconductive PDs, Schottky barrier PDs, and heterojunction PDs .…”

Fully Transparent and High‐Performance ε‐Ga2O3 Photodetector Arrays for Solar‐Blind Imaging and Deep‐Ultraviolet Communication

“…Furthermore, the film has a steep absorption edge of around 280 nm, and the ε‐Ga 2 O 3 film optical bandgap is estimated to be approximately 4.9 eV from the Tauc plot. [ 37 ] In this study, three transparent electrodes of ITO, AZO, and IGZO are used to fabricate fully transparent MSM‐type SBDU PDAs (5 × 4). The structure of a single PD is shown in the inset of Figure 1c.…”

Aqueous‐Printed Ga2O3 Films for High‐Performance Flexible and Heat‐Resistant Deep Ultraviolet Photodetector and Array

“…Flexible Ga 2 O 3 DUV photodetectors have been studied based on traditional sputter or atomic layer deposition technologies and have achieved decent performance. [26][27][28][29] However, these mainstream top-down methods usually have rigorous requirements for substrates and vacuum conditions, limiting the largearea growth of Ga 2 O 3 films on arbitrary substrates for flexible electronics. Moreover, there is serious material waste in the preparation of isolation devices, and the inevitable etching steps may also cause damage to the flimsy flexible substrate.…”