Chang, A.-C.A.-C.ChangLin, Y.-C.Y.-C.LinYen, H.-C.H.-C.YenYang, W.-C.W.-C.YangYang, Y.-F.Y.-F.YangWEN-CHANG CHEN2022-11-162022-11-16202226376113https://www.scopus.com/inward/record.uri?eid=2-s2.0-85126676286&doi=10.1021%2facsaelm.1c01345&partnerID=40&md5=ce79a2fe1368a770c765e6472746816ehttps://scholars.lib.ntu.edu.tw/handle/123456789/625169Organic phototransistor memory has received significant attention owing to its solution processability and flexibility, and its high transmission speed and low energy consumption with light operation provide a promising future in ultrahigh-density data storage devices. In this study, TIPS-functionalized organic small molecules, 9,10-bis[(triisopropylsilyl)ethynyl]anthracene (TIPS-3), 5,12-bis((triisopropylsilyl)ethynyl)tetracene (TIPS-4), and 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-5) were introduced and employed as the photogates, while polystyrene (PS) acted as the insulator in the floating gate electrets of phototransistor memory. The TIPS-functionalized structure enabled acenes to be solution-processable, and PS helped to trap charges efficiently. The devices were photowritten with different kinds of light and were electrically erased with a gate voltage of -60 V for 1 s. TIPS-4 exhibited the best memory performance and photoresponse with a stable current contrast of 105over 104s and a large shift in threshold voltage of 50 V to 450 nm light. The outstanding charge-trapping capability of TIPS-4 in the phototransistor memory was attributed to the favorable energy level alignment to the semiconducting layer. Notably, the significant photoresponse was ascribed to the singlet fission to triplet photodynamics of TIPS-4, which showed a delayed exciton lifetime providing enough time for charge transfer to the channel layer. The results of this study provide a design concept on organic small molecules in the floating gate electret. © 2022 American Chemical Society. All rights reserved.field-effect transistor; floating gate electret; photomemory; TIPS-acenes; triplet states[SDGs]SDG7Charge transfer; Charge trapping; Field effect transistors; Molecules; Threshold voltage; Virtual storage; Field-effect transistor; Floating gate electret; Floating gates; Functionalized; Organic phototransistors; Organic small molecule; Photomemory; Singlet fissions; TIPS-acenes; Triplet state; Energy utilizationjournal article10.1021/acsaelm.1c013452-s2.0-85126676286