Multisubstituted Azaisoindigo-Based Polymers for High-Mobility Ambipolar Thin-Film Transistors and Inverters

Abstract

Ambipolar semiconducting materials have great potential in complementary-like organic logic circuits. Accessing such logic circuits demands balanced hole and electron mobilities. However, the lack of ambipolar high-mobility polymer semiconductors with balanced charge carrier-transporting properties precludes the rapid development of organic logic circuits. In this context, structural modification of semiconductor materials to enhance the electron/hole transport is of great urgency. Herein, a multifunctionalization strategy is used to achieve this goal. Combined electron-withdrawing moieties involving fluorine and pyridinic nitrogen atoms can not only reduce the frontier molecular orbital energies but also planarize the polymer backbone, demonstrating synergetic effects on the control over the carrier injection process at the metal–semiconductor interface and microstructure-sensitive charge transport in the channel. A balanced ambipolar behavior with electron/hole mobilities of 3.88/3.44 cm2 V–1 s–1 was observed, and complementary-like inverters with high gains of greater than 200 were achieved. Microstructure and thin-film morphology were characterized to further reveal the relationship between device performances and macroscopic observables. This multifunctionalization strategy bodes well for developing new ambipolar semiconducting materials.

Recent Structural Engineering of Polymer Semiconductors Incorporating Hydrogen Bonds

“…P50 had balanced ambipolar properties, with hole and electron mobilities of 3.44 and 3.88 cm 2 V −1 s −1 , respectively. [120,124] Similar to fluorination on conjugated polymers, the trifluoromethyl group can also tune the charge transport behavior of polymer semiconductors. In addition, the higher hydrophobicity of trifluoromethyl is beneficial to expanding the scope of application of the devices.…”

“…P50 had balanced ambipolar properties, with hole and electron mobilities of 3.44 and 3.88 cm 2 V −1 s −1 , respectively. [ 120,124 ]…”

Semiconducting Polymers Based on Isoindigo and Its Derivatives: Synthetic Tactics, Structural Modifications, and Applications

“…[ 24 ] Based on M4 , many polymers with different donor moieties have been synthesized and exhibited excellent OFET performance, such as P17 and P18 . [ 24,94–96 ] Interestingly, the charge transport properties of these polymers to some extent depend on device structure. For example, P17 showed ambipolar transport with hole and electron mobilities of 2.33 and 0.78 cm 2 V −1 s −1 , respectively, in top‐gate bottom‐contact (TGBC) devices, and showed unipolar hole transport with mobility of 7.28 cm 2 V −1 s −1 in bottom‐gate bottom‐contact (BGBC) devices.…”

Synthetic strategies, molecular engineering and applications of semiconducting polymers based on diarylethylene units in electronic devices

“…139 P80 -based OFETs exhibited a balanced ambipolar transport with hole and electron mobilities of 3.44 and 3.88 cm 2 V −1 s −1 , respectively, and achieved complementary-like inverters with high gains. 140 The introduction of fluorine and pyridine nitrogen atoms improved the backbone planarity of P81–P84 by forming multiple conformation locks such as N⋯H, F⋯S, F⋯H, and S⋯O interactions. 69 P82 showed a higher hole mobility than did P81 because of the presence of more fluorine atoms.…”