Light-Emitting Microinlaid Spots Produced through Lateral Phase Separation by Means of Simple Single-Inkjet Printing

Area of Science:

• Materials Science
• Organic Electronics
• Nanotechnology

Background:

• Conventional vacuum-processed light-emitting diodes (LEDs) are complex to manufacture.
• There is a growing demand for high-performance, solution-processable LEDs.
• Existing methods often require intricate fabrication steps.

Purpose of the Study:

• To present a simplified, single-inkjet-printing process for fabricating microinlaid organic LEDs (OLEDs).
• To demonstrate the potential of inkjet-inlay structures for next-generation solution-processable LEDs.

Main Methods:

• Utilized a phase-separable material combination for single-inkjet printing.
• Employed convective and Marangoni flows in sessile droplets for site-selective etching and self-filling.
• Achieved microinlaid spots on a phase-separable poly(4-vinylpyridine) layer without preformed bank structures.

Main Results:

• Successfully fabricated microinlaid OLEDs with a spatial resolution of approximately 200 dpi.
• Achieved excellent performance in green microinlaid OLEDs, with a maximum brightness of ~13,000 cd/m² and maximum efficiency of ~14.2 cd/A.
• Demonstrated the capability to realize large-area inkjet-printed OLEDs using the microinlaid spot arrays.

Conclusions:

• The inkjet-inlay structure is a promising approach for high-performance, solution-processable LEDs.
• This method offers a simplified fabrication route compared to conventional techniques.
• The developed process enables efficient and high-resolution microfabrication of OLEDs.