TIPS-BDT Derivatives Based Charge Trapping Elements for Photoresponsive Organic Transistor Memories

Abstract

OFET-type optical memories using light bias as the fourth terminal enable low voltage electrical stresses to suffice in generating substantial memory window and photoassisted multibit storage. The undefined molecular structure and trapping mechanism of most storage media limit their practical applications. Herein, we report a series of charge trapping materials with the rigid and planar conjugated structure of benzo[1,2-b:4,5-b’]dithiophene (BDT) acting as the charge trapping site and photoresponsive group, while the insulated (triisopropylsilyl)acetylene (TIPS) unit is introduced to prevent the leakage path of the charge. The pentacene-based OFET memory with solution-processing TTIPS-BDT shows fast trapping speed, tunable ambipolar memory, large memory window and reliable charge retention, which is obviously improved compare to the performance of BDT and DTIPS-BDT devices. In addition, the charge trapping, memory characteristics and photoresponsive behaviors are also discussed in detail. The TTIPS-BDT device shows a specific response to green light illumination. This study suggests that BDT derivatives serving as charge trapping elements possess potential applications in future photoresponsive memory and plastic electronics.

Keywords

Molecular electronics / Electron transfer / Organic field-effect transistor memory / Charge trapping / BDT derivatives / Photoresponsive behavior / Memory window / Light illumination / Molecular devices / Charge carrier injection / Charge separation

RIGHTS & PERMISSIONS

2025 SIOC, CAS, Shanghai, & WILEY-VCH GmbH