Polyarylamine-Based Polymeric Electret with Tunable Pendant Groups for Photorecoverable Organic Transistor Memory

Polyarylamine-based dielectric electrets and pentacene as p-type semiconductors have been utilized to fabricate photoresponsive flash transistor memories. In this study, three polyarylamines, PTTC (poly(5-(4-(diphenylamino)phenyl)thiophene-2-carbonitrile)), PTTP (poly( N, N -diphenyl-4-(5-phenylthiophen-2-yl)aniline)), and PDTPmC (poly(2-(5-(diphenylamino)thiophen-2-yl)pyrimidine-5-carbonitrile)), with different pendant moieties, have been synthesized and characterized. They have been investigated for their ability to trap holes and photorecovery behaviors. The PDTPmC electret, which features a high dipole moment, coplanar conformation, and highly conjugated structure, has demonstrated an outstanding hole-trapping capability with a memory window of 106 V and photorecoverability under light irradiation. The coplanar donor–acceptor configuration converging diphenylamine and thiophene-pyrimidine provides sufficient hole-trapping sites and delocalization ability for photoexcitation excitons. The PDTPmC -based memory device exhibits excellent switching reliability of electrical programming and optical erasing for 200 cycles, with a stable readout current ratio of approximately 10 5 . This study proposes a polymer electret design approach to achieve high-performance transistor memory and photorecording device characteristics.