Light-Sensing Properties of Amorphous Vanadium Oxide Films Prepared by RF Sputtering

Area of Science:

• Materials Science
• Thin Film Technology
• Optoelectronics

Background:

• Vanadium oxide (V_xO_y) thin films are crucial for optoelectronic applications.
• Controlling film properties is key to optimizing device performance.
• Low-temperature deposition methods are desirable for industrial scalability.

Purpose of the Study:

• To investigate the structural and light-sensing properties of vanadium oxide thin films.
• To analyze the effect of Ar:O₂ flow rates on film characteristics.
• To evaluate the performance of Si/SiO₂/V_xO_y/TiN heterostructures as photodetectors.

Main Methods:

• Thin films prepared via RF sputtering at low temperature (65 °C).
• Characterization using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM-EDX), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS).
• Performance evaluation of fabricated heterostructures under UV, VIS, and NIR light excitation.

Main Results:

• Amorphous V_xO_y films with smooth surfaces were obtained.
• Increased oxygen content led to the formation of the V₂O₅ phase, confirmed by XPS.
• Photodetector performance (responsivity, detectivity, linear dynamic range) improved with higher O/V ratios.

Conclusions:

• The O/V ratio in vanadium oxide thin films significantly impacts their optical properties and photodetector performance.
• Low-temperature sputtered V_xO_y films demonstrate promising potential for photodetector applications.
• Performance achieved is comparable to detectors based on crystalline V₂O₅ or VO₂.