Gallium oxide (Ga2O3) is an emerging semiconductor for advanced optoelectronic applications owing to its suitable bandgap and advantageous electronic characteristics. While amorphous Ga2O3 is highly desired for low-cost and large-scale device application, it suffers from high dark current and slow response speed for practical ultraviolet photodetection. Here we integrate a polar aluminum nitride (AlN) template with amorphous Ga2O3 to fabricate a fast-response metal semiconductor metal (MSM) photodetector. It is revealed that the carrier transport and device performance strongly depend on the polarization direction of the AlN template. With a downward polarization from an Al-polar AlN layer, the Ga2O3 photodetector achieves an optimized performance with a lower dark current of 0.015 nA, a higher photo-to-dark current ratio of 104, a faster response speed of 31 ms and a recovery time of 22 ms. This study demonstrates an effective route of engineering carrier transport via the external spontaneous polarization for fabricating high-performance solar-blind photodetectors.

Fast-Response Amorphous Ga₂O₃ Solar-Blind Ultraviolet Photodetectors Tuned by a Polar AlN Template

High deep‐ultraviolet (DUV) sensitivity and excellent flexibility of ultrathin gallium oxide (Ga2O3) film with an ultrawide bandgap endow its extreme propensity in flexible DUV photodetector especially for space exploration and wearable electronics. However, an efficient strategy with high throughput and low cost is highly deficient to realize flexible and robust Ga2O3 DUV photodetectors to face potential harsh environments. In this work, flexible and heat‐resistant Ga2O3 DUV photodetectors based on optimized inkjet printing with environmental‐friendly aqueous solvent are demonstrated. The dynamic evolution from Ga(NO3)3 precursor to crystalline Ga2O3 film has been explicitly uncovered. Photodetectors based on printed ultrathin Ga2O3 films on rigid substrate exhibit outstanding performance, including high photo‐to‐dark current ratio about 106, considerable responsivity of 1.3 A W−1, superior detectivity of 1.46 × 1014 Jones, and fast decay time of 0.026 s under 254 nm illumination. In addition, flexible devices on mica substrate not only retain outstanding photoelectrical performance, but also demonstrate excellent mechanical flexibility and thermal stability. Moreover, benefiting from the uniformity of the pixels by high‐throughput inkjet printing, the Ga2O3 DUV photodetector array presents excellent sharp‐imaging capability. This work provides a feasible strategy for printable, flexible, and harsh‐environment‐resistant Ga2O3 DUV photodetectors toward space exploration and wearable electronics.

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

Ga2O3 is a wide bandgap semiconductor suitable for solar‐blind photodetection, but there exist two issues for Ga2O3‐based photodetectors: first, it is difficult to achieve reliable p‐type Ga2O3 and therefore form a homojunction photodetector, and the other is related with the slow response speed of Ga2O3‐based photodetectors. In this work, a self‐powered solar‐blind photodetector with a fast response using a p‐GaN/i‐Ga2O3/n‐Ga2O3 (pin) heterojunction with a fully depleted active region is realized, where i‐Ga2O3 serves as the main light‐absorbing active region. The device exhibits good self‐powered characteristics with a high responsivity of 72 mA W−1, a high photo‐to‐dark current ratio of 18 800, a high specific detectivity of 3.22 × 1012 Jones, and a fast response speed with a rise time/decay time of 7 ms/19 ms, respectively, without an external power supply. A detailed study of the interfacial electronic structure between p‐GaN and i‐Ga2O3 reveals a conduction band offset and valence band offset of 0.16 and 1.37 eV, respectively. Meanwhile, it has a large built‐in potential of 1.03 eV and a wide depletion region width of 235 nm in the i‐Ga2O3 side of heterojunction. It is believed that excellent device performance comes from a suitable energy band structure and wide depletion region.

A Fast Self‐Powered Solar‐Blind Ultraviolet Photodetector Realized by Ga2O3/GaN PIN Heterojunction with a Fully Depleted Active Region

High-performance phototransistor-based solar-blind (200-280 nm) ultraviolet (UV) photodetectors (PDs) are constructed with a low-cost thin-film ZnO/Ga2O3 heterojunction. The optimized PD shows high spectral selectivity (R254/R365 > 1 × 103) with a photo-to-dark current ratio of ∼104, a responsivity of 113 mA/W, a detectivity of 1.25 × 1012 Jones, and a response speed of 41 ms under 254 nm UV light irradiation. It is found that the gate electrode of a three-terminal phototransistor can amplify the responsivity and increase the photo-to-dark current ratio because of the different densities of field-induced electrons at different gate biases. In addition, the built-in electric field at the ZnO/Ga2O3 heterojunction interface can control the distribution of the photoinduced electrons and the total conductivity of the heterojunction, which can further enhance device performance. Together with the simple fabrication process, the achieved results suggest that the three-terminal ZnO/Ga2O3 heterojunction phototransistor is a promising candidate for highly sensitive solar-blind PDs.

High-Performance Solar-Blind UV Phototransistors Based on ZnO/Ga2O3 Heterojunction Channels.

Zinc oxide (ZnO) nanomaterials have attracted much attention in UV photodetectors owing to the suitable band gap and high photoelectric conversion efficiency. However, the loose structure of nanomaterials assembled by a low-temperature process cannot meet the mechanical requirements of flexible photodetectors. The high dark current caused by defects in ZnO severely drags down the response performance of photodetectors. To address these issues, we have proposed a novel strategy for constructing flexible photodetectors based on ZnO and poly(ethylene glycol) (PEG) composites. Inspired by the sunscreen, the addition of PEG can enhance the interaction of ZnO nanoparticles, thus improving the film-forming ability and the mechanical endurance of the composites. By coating the ZnO/PEG composite on a common printing paper, the flexible photodetector shows unexpected good performance, such as a high responsivity of 1.77 A·W–1 and a large specific detectivity of 3.89 × 1013 Jones. Notably, a giant on–off ratio of up to 1.99 × 105 has been achieved by suppression of dark current. The device also exhibits satisfactory mechanical flexibility after long-term bending tests. In addition, the low-cost raw materials and scalable manufacturing processes further expand its application prospects in flexible optoelectronic technologies. 

Sunscreen-Inspired ZnO/PEG Composites for Flexible Ultraviolet Photodetectors with a Giant On–Off Ratio

Piezoelectric effect enhanced flexible UV photodetector based on Ga2O3/ZnO heterojunction

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

L. Fei

Author Tools

Chat about Author

Papers

Piezoelectric effect enhanced flexible UV photodetector based on Ga2O3/ZnO heterojunction