Programmable digital printing of organic single crystals for integrated electronics

Area of Science:

• Materials Science
• Organic Electronics
• Additive Manufacturing

Background:

• Achieving precise control over organic semiconductor arrays in additive manufacturing (AM) is crucial for high-performance organic integrated electronics.
• Conventional AM methods struggle with controlling crystallinity and orientation due to complex crystallization kinetics under non-equilibrium conditions.

Purpose of the Study:

• To report a mask-free, pattern-free printing method for high-resolution organic single-crystal arrays with controlled location, orientation, and aspect ratio.
• To demonstrate a universally applicable mechanism for controlling organic semiconductor crystallization during printing.

Main Methods:

• Establishment of a dynamic liquid-crystal area (DLCA) beneath the printing nozzle.
• Tuning DLCA geometry via applied voltage and speed to govern solute transport, solvent evaporation, and nucleation.
• Utilizing classical theory and transition region theory to support the observed mechanism.

Main Results:

• Successful mask-free, pattern-free printing of organic single-crystal arrays with controlled location, orientation, and aspect ratio.
• Demonstrated highly uniform mobility in printed organic single-crystal arrays (12-15% variation), the most uniform achieved by electrohydrodynamic printing to date.
• Integrated printed organic single-crystal patterns into a functional 96 organic field-effect transistor photodetector array.

Conclusions:

• The developed DLCA method enables precise control over organic semiconductor crystal growth during AM.
• This approach is universally applicable to solution-processable organic semiconductors, paving the way for advanced organic integrated electronics.
• The printed arrays show potential for applications in information recognition and complex electronic systems.