Solution‐processed polar hydroxyl containing polymers such as poly(4‐vinylphenol) are widely utilized in organic filed‐effect transistors (OFETs) due to their high dielectric constant (k) and excellent insulating properties owing to the crosslinking through their hydroxyl groups. However, hydroxyl functionalities can function as trapsites, and their crosslinking reactions decrease the k value of materials. Hence, in this study, new solution‐processable copolymers containing both carboxyl and hydrophobic functionalities are synthesized. A fluorophenyl azide (FPA) based UV‐assisted crosslinker is also employed to promote the movement of polar carboxyl groups toward the bulk region and the hydrophobic functionalities to the surface region, thereby maintaining the high‐k characteristics and hydrophobic surface in thin film. Thus, the addition of an FPA crosslinker eliminates the trapsites on the surface, allowing a stable operation and efficient charge transport. Additionally, the solution‐processability enables the production of uniform and thin films to yield OFETs with stable and low‐voltage driving characteristics. The printed layers are also applied as gate dielectrics for floating gate memory devices and in integrated one‐transistor‐one‐transistor based memory cells, displaying their excellent memory performance. The synthesis and fabrication strategies employed in this study can become useful guidelines for the production of high‐k dielectrics for stable OFETs and other applications.

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A novel fluorinated organic–inorganic (O–I) hybrid sol—gel based material, named FAGPTi, is successfully synthesized and applied as a gate dielectric in flexible organic thin‐film transistors (OTFTs). The previously reported three‐arm‐shaped alkoxysilane‐functionalized amphiphilic polymer yields a stable O–I hybrid material consisting of uniformly dispersed nanoparticles in the sol‐state. Here, a fluorinated precursor is introduced into the system, making it possible to realize more stable spherical composites. This results in long‐term colloidal stability (≈1.5 years) because composite growth is strongly inhibited by the presence of fluorine groups with intrinsically strong repulsive forces. Additionally, the FAGPTi film is easily deposited via thermally annealed sol–gel reactions; the films can be successfully fabricated through the printing method, and exhibit excellent flexibility and enhanced insulating properties compared to existing materials. OTFTs with FAGPTi layers show highly stable driving characteristics under severe bending conditions (1.9% strain). Integrated logic devices are also successfully operated with these OTFTs. Additionally, it can facilely be applied to amorphous indium‐gallium‐zinc‐oxide (a‐IGZO) TFT devices other than OTFT. Therefore, this synthetic strategy can provide useful insights into the production of functional O–I hybrid materials, enabling the efficient fabrication of electronic materials and devices exhibiting these properties.

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Low-voltage-operating high-performance organic field-effect transistors (OFETs) are regarded as the building blocks of analog and digital integrated circuits for next-generation electronics. To fulfill this, such an OFET must have high-dielectric constant (k) characteristics for increasing the capacitance values to make enough of a field-effect charge, a hydrophobic surface that does not cause charge trapping, and a low leakage current property to guarantee operating stability. This study demonstrates a new strategy to induce high-k characteristics (>8) with durable polysilsesquioxane (PSQ)-based dielectrics. This strategy involves realizing a dipolar side-chain reorientation under an electric field and its applications to low-voltage-driving OFETs showing high field-effect mobility levels as high as 27 cm 2 V -1 s -1 . Different PSQs are characterized, and the differences in their characteristics lead to distinct polarization phenomena, resulting in different hysteresis behaviors during device operation. The printed unit devices can also be fabricated on flexible platforms and integrated devices through these materials and show robust switching or memory performances under low-voltage-operation conditions. Therefore, this facile but powerful synthesis strategy for high-k PSQ dielectrics can pave a new path for the production of practical printable high-k dielectrics for organic electronics and hence realize next-generation integrated electronics.

A π-conjugated polymer semiconductor, PBDTTTffPI, was synthesized for use as an organic semiconductor suitable for electrohydrodynamic (EHD) jet printing technology. Bulky alkylation of the polymer gave PBDTTTffPI good solubility in several organic solvents. EHD jet printing using PBDTTTffPI ink produced direct patterns of polymer semiconductors while maintaining smooth surface morphologies and crystal structures similar to those of spin-coated PBDTTTffPI films. EHD-jet-printed PBDTTTffPI was appropriate for use as a semiconductor layer in organic field-effect transistors (OFETs) and logic gates. OFETs that used EHD-jet-printed PBDTTTffPI had better electrical characteristics than devices that used spin-coated semiconductor films. When a dielectric material (Al2O3) with a high dielectric constant was introduced, the jet-printed PBDTTTffPI operated well at low voltages. Integrated devices such as inverters, NAND gates, and NOR gates were fabricated by printing PBDTTTffPI patterns and showed good switching behaviors. Therefore, the use of printable PBDTTTffPI provides an advance toward fabrication of practical integrated arrays in next-generation devices.

The addition of hardeners to the PEDOT:PSS composites enhances both electrical and physical properties to satisfy the requirements for electrode usages in organic electronic devices.

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