Photo‐/Thermal‐Responsive Field‐Effect Transistor upon Blending Polymeric Semiconductor with Hexaarylbiimidazole toward Photonically Programmable and Thermally Erasable Memory Device

Abstract

The past decades have witnessed the rapid development of organic and polymeric semiconductors with high charge mobilities, [1][2][3][4] thanks to the design and synthesis of various conjugated molecules and macromolecules along with the manipulation of self-assembly and interfacial structures. Performances for both p-channel and n-channel field-effect transistors (FETs) are now comparable to and even higher than those of traditional amorphous silicon FETs. Moreover, the promising applications of organic and polymeric semiconductors in low-cost logic circuits (e.g., radio frequency identification tags) and flexible electronics have been successfully demonstrated. [5] New conjugated molecules and macromolecules are being continuously explored for boosting the performances of FETs. Meanwhile, stimuli-responsive organic semiconducting materials, for which the semiconducting properties can be tuned by external stimuli other than electrical fields such as light irradiation and heating, have received increasing attentions in recent years. [6][7][8][9][10][11] This is because multifunctional devices can be constructed with such stimuli-responsive organic semiconducting materials. For instances, Samori and co-workers reported the reversible modulation of device currents for FETs with photoresponsive semiconducting layers by blending of photochromic diarylethenes with organic semiconductors. [8a-c] Photochromic molecules were also inserted into the dielectric layer and the electrode-semiconductor interface to fabricate FETs with photoregulation functions. [10] We have just devised a new approach to photoresponsive polymeric semiconductor by incorporating azobenzene units into the side chains. [11a] Furthermore, these photoresponsive FETs were successfully utilized to fabricate memory devices for which the programming, reading and erasing signals are different without mutual interferences. [10b] It is noted that FETs with organic and polymeric semiconductors have also been investigated for nonvolatile memory It is shown that the semiconducting performance of field-effect transistors (FETs) with PDPP4T (poly(diketopyrrolopyrrolequaterthiophene)) can be reversibly tuned by UV light irradiation and thermal heating after blending with the photochromic hexaarylbiimidazole compound (p-NO 2 -HABI). A photo-/thermal-responsive FET with a blend thin film of PDPP4T and p-NO2 -HABI is successfully fabricated. The transfer characteristics are altered significantly with current enhanced up to 10 6 -fold at V G = 0 V after UV light irradiation. However, further heating results in the recovery of the transfer curve. This approach can be extended to other semiconducting polymers such as P3HT (poly(3-hexyl thiophene)), PBTTT (poly(2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b] thiophene)) and PDPPDTT (poly(diketopyrrolopyrrole-dithienothiophene)). It is hypothesized that TPIRs (2,4,5-triphenylimidazolyl radicals) formed from p-NO 2 -HABI after UV light irradiation can interact with charge defects at the gate dielectric-semiconducto...

Application of organic field-effect transistors in memory

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High performance nonvolatile organic field‐effect transistor memory devices based on pyrene diimide derivative

“…Organic electronic devices, such as organic field‐effect transistors (OFETs), 1 organic solar cells (OSCs), 2,3 and organic memory devices (OMs) 4,5 have attracted great attention due to their advantages of low cost fabrication, light weight, and flexibility. Among them, organic memristor, 6 especially the non‐volatile memory device based on the OFET structure (OFET‐NVM), 7 is considered new generation of portable high‐density storage devices for future organic integrated circuits and portable electronic devices 8 . Considerable efforts have been devoted to improve the parameters of OFET‐NVMs, including the memory window, on/off ratio, programming/erasing voltage, switching speed, retention time, and endurance capability 9 .…”

In Situ Control of Multicolor Luminescence over the Entire Visible Spectral Region in a Single Chromophore by Sol–Gel Transformation and Dynamic Metal–Ligand Coordination

“…[1][2][3][4][5] In recent years, these smart materials have drawn significant interest due to their wide range of applications in sophisticated technologies and daily life. [6][7][8] In particular, research on multicolor emitting chromophores is of fundamental importance, [9][10][11] as they can serve as key precursors in achieving advanced functions of signal generation, [12][13][14][15] information storage and processing, [16][17][18] displays, [19][20][21][22] optical imaging, [23][24][25] and anticounterfeiting. [26][27][28][29][30][31] Control of molecular switches has been demonstrated as an effective way to modulate the luminescence conversion processes of chromophores.…”