Single-Crystal Diamond Nanowires Embedded with Platinum Nanoparticles for High-Temperature Solar-Blind Photodetector

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Diamond is a promising ultrawide-bandgap semiconductor for photodetectors in extreme environments.
• Oxygen termination at high temperatures severely limits diamond photodetector photoresponsivity.

Purpose of the Study:

• To develop high-performance diamond photodetectors for harsh conditions.
• To overcome the limitations of oxygen-terminated diamond surfaces at elevated temperatures.

Main Methods:

• Fabrication of single-crystalline diamond nanowires (DNWs) embedded with platinum (Pt) nanoparticles.
• Utilizing Pt film deposition and chemical vapor deposition (CVD) homoepitaxial growth.
• Dewetting of Pt nanoparticles during CVD for uniform embedding within DNWs.

Main Results:

• Pt nanoparticle-embedded DNWs achieved a responsivity of 68.5 A W⁻¹ at room temperature under 220 nm illumination, a 2000x improvement over bulk diamond.
• Responsivity dramatically increased with temperature, reaching 3098.7 A W⁻¹ at 275 °C.
• Enhanced performance attributed to 1D nanowire structure, deep-level defects, Pt nanoparticle plasmon resonance, and Schottky junctions.

Conclusions:

• Pt nanoparticle-embedded DNWs offer a significant advancement for deep ultraviolet detection in extreme environments.
• The developed photodetectors show potential for applications in aerospace and industrial monitoring.
• Synergistic effects enhance optical absorption, carrier generation, and separation efficiency for superior performance.