Piezo-phototronic Effect Enhanced UV/Visible Photodetector Based on Fully Wide Band Gap Type-II ZnO/ZnS Core/Shell...

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Wide bandgap semiconductor heterojunctions are crucial for advanced photodetectors.
• ZnO and ZnS offer tunable electronic and optical properties.
• Type-II heterojunctions enable unique charge carrier dynamics.

Purpose of the Study:

• To fabricate a high-performance broadband UV/visible photodetector.
• To investigate the role of type-II heterojunctions in photon detection.
• To enhance photodetector performance using the piezo-phototronic effect.

Main Methods:

• Fabrication of ZnO/ZnS type-II heterojunction core/shell nanowire arrays.
• Characterization of the photodetector's response to UV and visible light.
• Analysis of the piezo-phototronic effect on charge carrier transport.

Main Results:

• Successful fabrication of a broadband UV/visible photodetector.
• Detection of photons with energies below the individual band gaps (2.2 eV).
• Three orders of magnitude change in relative responsivity due to the piezo-phototronic effect.

Conclusions:

• The ZnO/ZnS type-II heterojunction facilitates detection of lower energy photons.
• The piezo-phototronic effect significantly enhances photodetector performance.
• Demonstration of a prototype 3D core/shell nanowire array photodetector with improved capabilities.