Doped Highly Crystalline Organic Films: Toward High-Performance Organic Electronics

Area of Science:

• Organic electronics
• Materials science
• Semiconductor physics

Background:

• Current organic electronic devices use disordered films with low carrier mobility.
• High charge carrier mobility is crucial for high-performance organic diodes and transistors.
• Organic single crystals offer high mobility but are difficult to manufacture and dope.

Purpose of the Study:

• To develop a method for creating highly ordered, doped organic thin films.
• To achieve high charge carrier mobilities in organic materials.
• To demonstrate the performance of these films in organic electronic devices.

Main Methods:

• Preparation of triclinic rubrene crystals via abrupt heating of amorphous layers.
• Electrical doping during epitaxial growth for hole or electron conduction.
• Analysis of space charge limited current to determine vertical mobilities.

Main Results:

• Record vertical mobilities of 10.3(49) cm^2 V^-1 s^-1 achieved in doped rubrene films.
• Fabrication of monolithic pin-diodes with operating frequencies over 1 GHz.
• Demonstration of hole and electron conduction in the crystalline films.

Conclusions:

• Highly ordered, doped organic thin films can be prepared on various substrates.
• This approach enables high-performance organic electronic devices with superior mobility.
• The findings pave the way for future high-performance organic devices based on crystalline thin films.