Optical memory characteristics of solution-processed organic transistors with self-organized organic floating gates for printable multi-level storage devices

Application of organic field-effect transistors in memory

“…Naito and co-workers further demonstrated a light-assisted programming multi-level storage device using TIPS-PEN as a floating gate capture layer and P3HT as the semiconductor layer. 90 The memory window of the device was greater than 30, and the retention time was longer than 10 6 , as shown in Fig. 15.…”

“…88,89 Similar to the voltage between the gate and the source, the photo-generated carriers in the floating gate layer form an additional internal electric field that affects the carriers in the conductive channel. Due to the adjustability of the light intensity, photon storage devices have developed rapidly in multi-level storage, 79,83,84,[90][91][92] wearable sensors 93 and other applications. For example, Liu and co-workers reported a multi-level storage device using PS or PMMA as a modified layer (modified SiO 2 ) and pentacene or copper phthalocyaine (CuPc) as a semiconductor layer.…”

Recent Advances in Organic Phototransistors: Nonvolatile Memory, Artificial Synapses, and Photodetectors

“…Various organic photoactive molecules, including C 60 , [85] PCBM, [86] TIPSÀpentacene, [87] DPAÀCM, [88] and triphenylamine-based molecules, [89] have been incorporated as photogates into insulated polymer matrices of PVN, [85,86] PMMA, [87,88] polyamide, or polyimide. [89] Floating gate electrets comprising a photoactive molecule and insulated polymer can be used to program memory devices without gate bias and can enhance the chargetrapping capability within the bulk of the electret.…”

“…For example, Shiono et al reported a top‐gate/bottom‐contact device configuration comprising P3HT as the channel, PMMA/TIPS−pentacene as the electret, and CYTOP as the dielectric. [ 87 ] Their memory device could perform photoassisted electrical writing/erasing with blue/green/red light over a memory window of ≈25–30 V with a memory ratio of 10 2 –10 3 over 3000 s. Huang et al reported a hybrid floating gate comprising a triphenylamine‐based molecule (SM) and polyamide or polyimide. [ 89 ] During UV‐assisted electrical writing, PL emissions produced by the photogating molecules are absorbed by top pentacene, producing photoinduced excitons that are transduced into holes and electrons.…”

Tailoring the molecular weight of polymer additives for organic semiconductors

“…When organic semiconductors are blended with conjugated polymers, the binary system can give rise to intermolecular interactions between these two components. 163–168 For example, Chen et al reported that when two different types of conjugated polymers, including P3HT and regiorandom pentacene–bithiophene polymer (PnBT–RRa), were mixed with TIPS pentacene, the resultant binary system exhibited tunable intermolecular interactions that arise from both π–π interactions and hydrophobic interactions. The different extent of molecular structural similarity between TIPS pentacene and the conjugated polymer additives determines the intensity of intermolecular interactions.…”