High-performance flexible organic field effect transistors with print-based nanowires

Area of Science:

• Materials Science
• Electronics Engineering
• Nanotechnology

Background:

• High-performance flexible electronics require precisely fabricated components on large-area substrates.
• Existing methods for creating polymer nanowire arrays often struggle with alignment, uniformity, and transfer processes, impacting electrical properties.

Purpose of the Study:

• To present a universal coaxial focused electrohydrodynamic jet (CFEJ) printing technology for fabricating highly aligned polymer nanowire arrays.
• To demonstrate the capability of CFEJ printing for producing uniform, precisely positioned nanowires directly on flexible substrates without transfer.
• To evaluate the performance and uniformity of organic field-effect transistors (OFETs) fabricated using this technique.

Main Methods:

• Utilized coaxial focused electrohydrodynamic jet (CFEJ) printing to create 90-nm-diameter polymer nanowire arrays on flexible substrates.
• Employed indacenodithiophene-co-benzothiadiazole (IDT-BT) and poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8-BT) as model polymer semiconductors.
• Characterized the molecular arrangement within nanowires using 2D-Grazing Incidence X-ray Diffraction (2D-GIXRD).

Main Results:

• Successfully fabricated 5 cm² polymer nanowire arrays with minimal size variations using CFEJ printing.
• Observed a predominantly face-on π-stacking crystallite arrangement within the polymer nanowires, differing from thin films.
• Achieved high average hole mobility of 1.1 cm²/V·s in nanowire-based OFETs with good device uniformity.

Conclusions:

• CFEJ printing is a viable technique for batch manufacturing and integration of high-performance, scalable polymer nanowire OFET circuits.
• This method facilitates the use of organic polymer semiconductors in large-area electronic devices.
• The technology offers a new pathway for developing flexible displays and wearable electronics.