Meniscus-controlled printing of single-crystal interfaces showing extremely sharp switching transistor operation

Area of Science:

• Materials Science
• Organic Electronics
• Surface Science

Background:

• Meniscus shape is critical for solution-based thin-film processing.
• Uniform film growth is challenging on highly lyophobic surfaces, despite their potential for improved device performance.

Purpose of the Study:

• To demonstrate a technique for controlling solution menisci on highly lyophobic surfaces.
• To enable the fabrication of single-crystalline organic semiconductor (OSC) films on Cytop, a highly lyophobic material.
• To improve the performance of organic transistors by eliminating charge traps.

Main Methods:

• Utilizing a U-shaped metal film pattern on Cytop to initiate and sustain meniscus extension.
• Leveraging the growing edge of the OSC film to maintain meniscus stability during film growth.
• Fabricating organic semiconductor films and evaluating transistor performance.

Main Results:

• Successfully manufactured single-crystalline OSC films on the highly lyophobic Cytop surface.
• Achieved controlled and successive film growth by maintaining meniscus extension.
• Produced transistors with extremely sharp switching (subthreshold swing of 63 mV dec⁻¹).

Conclusions:

• The developed technique effectively controls solution menisci on challenging lyophobic surfaces.
• This method facilitates the production of high-quality OSC films and high-performance transistors.
• The technique holds potential for advancing the print production of functional electronic devices.