Ultraviolet Photodetecting and Plasmon-to-Electric Conversion of Controlled Inkjet-Printing Thin-Film Transistors

Area of Science:

• Materials Science
• Electronics Engineering
• Optoelectronics

Background:

• Thin-film transistors (TFTs) are crucial for electronic devices.
• Photodetection requires sensitive and efficient materials.
• Direct ink-jet printing offers precise fabrication capabilities.

Purpose of the Study:

• To demonstrate direct ink-jet printing of 3-D ZnO-based TFTs for UV and visible light photodetection.
• To investigate the effect of temperature-induced Marangoni flow on channel width.
• To enhance device performance using oxygen plasma treatment and explore plasmonic effects.

Main Methods:

• Direct ink-jet printing of ZnO-based TFTs with 3-D channel structures.
• Utilizing temperature-induced Marangoni flow to narrow channel width.
• Employing oxygen plasma treatment to improve electrical characteristics.
• Fabricating and characterizing metal-semiconductor junction structures for plasmon energy detection.

Main Results:

• Achieved channel width reduction from 318.9 ± 44.1 μm to 180.1 ± 13.9 μm via Marangoni flow.
• Enhanced switching I_ON/I_OFF ratio to approximately 10^5 using oxygen plasma treatment.
• Demonstrated superior photoresponse to UV illumination with >2 orders of magnitude increase in drain current.
• Observed negative threshold voltage shifts under visible light exposure in plasmonic devices.

Conclusions:

• Direct ink-jet printing is a viable technique for fabricating 3-D ZnO-based TFTs for UV and visible light sensing.
• Marangoni flow and oxygen plasma treatment are effective methods for optimizing TFT performance.
• The developed devices show promise for advanced UV photodetectors and plasmon energy detection.