Air-stable, solution-processed oxide p-n heterojunction ultraviolet photodetector
Do Young Kim1, Jiho Ryu, Jesse Manders
1Department of Materials Science and Engineering, University of Florida , Gainesville, Florida 32611, United States.
ACS Applied Materials & Interfaces
|January 11, 2014
Summary
A novel ultraviolet photodetector uses solution-processed inorganic materials for high gain. Interfacial charge injection in the p-n heterojunction enhances performance, controlled by annealing temperature.
Area of Science:
- Materials Science
- Optoelectronics
- Semiconductor Devices
Background:
- Development of efficient and stable ultraviolet (UV) photodetectors is crucial for various applications.
- Solution-processed inorganic materials offer a cost-effective and scalable alternative to traditional fabrication methods.
- All-inorganic p-n heterojunctions are promising for enhanced photodetector performance.
Discussion:
- This study demonstrates an air-stable, solution-processed all-inorganic p-n heterojunction UV photodetector.
- High gain, quantified by external quantum efficiency (EQE) up to 25,300%, is achieved.
- The gain mechanism is attributed to interfacial trap-induced charge injection at the Indium Tin Oxide (ITO)/Nickel Oxide (NiO) interface, driven by photogenerated holes trapped in the NiO film.
Key Insights:
- Solution-processed Nickel Oxide (NiO) and Zinc Oxide (ZnO) serve as effective p-type and n-type UV sensitizing materials, respectively.
- The photodetector exhibits excellent air stability.
- Post-annealing temperature of the solution-processed NiO films critically controls the photodetector's gain, as confirmed by X-ray photoelectron spectroscopy (XPS) analysis.
Outlook:
- Further optimization of annealing conditions could lead to even higher performance UV detectors.
- This work paves the way for low-cost, high-performance UV sensing technologies.
- Exploring alternative inorganic materials for solution processing could broaden the application scope.
