Ga₂O₃-Based Solar-Blind Position-Sensitive Detector for Noncontact Measurement and Optoelectronic Demodulation

Abstract

As a kind of photodetector, position-sensitive-detectors (PSDs) have been widely used in noncontact photoelectric positioning and measurement. However, fabrications and applications of solar-blind PSDs remain yet to be harnessed. Herein, we demonstrate a solar-blind PSD developed from a graphene/Ga2O3 Schottky junction with a 25-nanometer-thick Ga2O3 film, in which the absorption of the nanometer-thick Ga2O3 is enhanced by multibeam interference. The graphene/Ga2O3 junction exhibits a responsivity of 48.5 mA/W and a rise/decay time of 0.8/99.8 μs at zero bias. Moreover, the position of the solar-blind spot can be determined by the output signals of the PSD. Using the device as a sensor of noncontact test systems, we demonstrate its application in measurement of angular, displacement, and light trajectory. In addition, the position-sensitive outputs have been used to demodulate optical signals into electrical signals. The results may prospect the application of solar-blind PSDs in measurement, tracking, communication, and so on.

High-Performance Self-Powered Photodetector Based on the Lateral Photovoltaic Effect of All-Inorganic Perovskite CsPbBr3 Heterojunctions

“…The performance parameters of PSDs developed from various materials are displayed in Table S1 of the Supporting Information. It is obvious that the responsivity and the response time of the CsPbBr 3 -based PSD are superior to those of most PSDs. ,,,− …”

A Time‐Division Position‐Sensitive Detector Image System for High‐Speed Multitarget Trajectory Tracking

“…The TD‐PSD locates projected light spots through lateral photoelectric effects. [ 6e,7 ] The structure of TD‐PSD is shown in Figure a. The CVD graphene sheet synthesized by chemical vapor deposion is wet transferred onto an n‐doped Si substrate with a thin light p‐doped layer, forming a Schottky heterojunction.…”

“…Moreover, PSDs based on nanoscale films, including graphene, MoS 2 , GIGS, and Ga 2 O 3, have shown excellent performances in terms of responsivity, response time, and spectral range. [ 6 ] Due to the difference in detection mechanism with the array‐type image sensor, some of the above issues in high‐speed trajectory tracking can be solved. However, PSD is not able to distinguish multiple targets according to the mixed carrier concentration distribution.…”

Humidity-Resistant Solar-Blind Ultraviolet Photodetectors Based on Solution-Processed Amorphous Scandium Oxide Films

“…The wide band gap of 4.5–5.2 eV makes it widely used for the fabrication of UV photodetectors, − which can realize ultraviolet detection without filters or a composite structure. However, the small lattice energy owned by β-Ga 2 O 3 is easy to cause the defects such as oxygen vacancies and gap gallium during the synthesis process, which will thus deviate the prepared β-Ga 2 O 3 from an ideal chemical ratio. − Actually, except for β-Ga 2 O 3 , other wide band gap semiconductors such as ZnO and Lu 2 O 3 as well as the ternary oxides like MgZnO are also possible choices for SBUV detection but with some problems coexisting. For example, Lu 2 O 3 is so sensitive to humidity changes that it will be prone to hygroscopic reactions in air; ternary oxides are easy to produce uncontrollable alloying processes represented by phase separation.…”