Significant Performance Improvement in n-Channel Organic Field-Effect Transistors with C₆₀ :C₇₀ Co-Crystals Induced...

Area of Science:

• Materials Science
• Organic Electronics
• Nanotechnology

Background:

• Solution-processed organic field-effect transistors (OFETs) are promising for flexible electronics.
• Current n-channel OFETs face challenges in charge carrier mobility, scalability, and stability.
• Interfacial engineering of source/drain electrodes is a key strategy for device improvement.

Purpose of the Study:

• To investigate the effect of poly(2-ethyl-2-oxazoline) (PEOz) nanodots on n-channel OFET performance.
• To enhance electron mobility and overall device characteristics in OFETs utilizing soluble fullerene semiconductors.
• To explore the mechanism behind mobility enhancement through interfacial modification.

Main Methods:

• Fabrication of n-channel OFETs with source/drain electrodes modified by PEOz nanodots.
• Utilizing a range of soluble fullerene semiconductors, including C60 and C70 blends.
• Characterization of device performance, focusing on electron mobility and charge injection efficiency.
• Analysis of the influence of PEOz on electrode work function and film morphology.

Main Results:

• PEOz nanodot modification significantly enhanced electron mobility in n-channel OFETs.
• A notable eighteen-fold increase in mobility was observed for C60:C70 blend films, rising from 0.1 to 2.1 cm²/Vs.
• The improvement is attributed to reduced electrode work function and PEOz-induced formation of a face-centered-cubic C60:C70 co-crystal structure.

Conclusions:

• PEOz nanodots are an effective interfacial engineering strategy for improving n-channel OFET performance.
• This approach addresses key limitations of soluble fullerene-based OFETs, paving the way for commercialization.
• The findings highlight the potential of PEOz for advancing flexible and printed electronics.