N‐Type Self‐Assembled Monolayer Field‐Effect Transistors and Complementary Inverters

This work describes n‐type self‐assembled monolayer field‐effect transistors (SAMFETs) based on a perylene derivative which is covalently fixed to an aluminum oxide dielectric via a phosphonic acid linker. N‐type SAMFETs spontaneously formed by a single layer of active molecules are demonstrated for transistor channel length up to 100 μm. Highly reproducible transistors with electron mobilities of 1.5 × 10^?3 cm² V^?1 s^?1 and on/off current ratios up to 10⁵ are obtained. By implementing n‐type and p‐type transistors in one device, a complimentary inverter based solely on SAMFETs is demonstrated for the first time.     

Rationally Engineered Electrodes for a High‐Performance Solid‐State Cable‐Type Supercapacitor

Wire‐shaped electrodes for solid‐state cable‐type supercapacitors (SSCTS) with high device capacitance and ultrahigh rate capability are prepared by depositing poly(3,4‐ethylenedioxythiophene) onto self‐doped TiO₂ nanotubes (D‐TiO₂) aligned on Ti wire via a well‐controlled electrochemical process. The large surface area, short ion diffusion path, and high electrical conductivity of these rationally engineered electrodes all contribute to the energy storage performance of SSCTS. The cyclic voltammetric studies show the good energy storage ability of the SSCTS even at an ultrahigh scan rate of 1000 V s^?1, which reveals the excellent instantaneous power characteristics of the device. The capacitance of 1.1 V SSCTS obtained from the charge–discharge measurements is 208.36 µF cm^?1 at a discharge current of 100 µA cm^?1 and 152.36 µF cm^?1 at a discharge current of 2000 µA cm^?1, respectively, indicating the ultrahigh rate capability. Furthermore, the SSCTS shows superior cyclic stability during long‐term (20 000 cycles) cycling, and also maintains excellent performance when it is subjected to bending and succeeding straightening process.     

Polymer‐Based Organic Field‐Effect Transistors with Active Layers Aligned by Highly Hydrophobic Nanogrooved Surfaces

In this study, polymer‐based organic field‐effect transistors (OFETs) that exhibit alignment‐induced mobility enhancement, very small device‐to‐device variation, and high operational stability are successfully fabricated by a simple coating method of semiconductor solutions on highly hydrophobic nanogrooved surfaces. The highly hydrophobic nanogrooved surfaces (water contact angle >110°) are effective at inducing unidirectional alignment of polymer backbone structures with edge‐on orientation and are advantageous for realizing high operational stability because of their water‐repellent nature. The dewetting of the semiconductor solution is a critical problem in the thin film formation on highly hydrophobic surfaces. Dewetting during spin coating is suppressed by surrounding the hydrophobic regions with hydrophilic ones under appropriate designs. For the OFET array with an aligned terrace‐phase active layer of poly(2,5‐bis(3‐hexadecylthiophene‐2‐yl)thieno[3,2‐b]thiophene), the hole mobility in the saturation regime of 30 OFETs with channel current direction parallel to the nanogrooves is 0.513 ± 0.018 cm² V^?1 s^?1, which is approximately double that of the OFETs without nanogrooves, and the intrinsic operational stability is comparable to the operational stability of amorphous‐silicon field‐effect transistors. In other words, alignment‐induced mobility enhancement and high operational stability are successfully achieved with very small device‐to‐device variation. This coating method should be a promising means of fabricating high‐performance OFETs.     

Enhanced Performance of Self‐Assembled Monolayer Field‐Effect Transistors with Top‐Contact Geometry through Molecular Tailoring,Heated Assembly,and Thermal Annealing

Low‐voltage self‐assembled monolayer field‐effect transistors (SAMFETs) that operate under an applied bias of less than ?3 V and a high hole mobility of 10^?2 cm² V^?1 s^?1 are reported. A self‐assembled monolayer (SAM) with a quaterthiophene semiconducting core and a phosphonic acid binding group is used to fabricate SAMFETs on both high‐voltage (AlO_x/300 nm SiO₂) and low‐voltage (HfO₂) dielectric platforms. High performance is achieved through enhanced SAM packing density via a heated assembly process and through improved electrical contact between SAM semiconductor and metal electrodes. Enhanced electrical contact is obtained by utilizing a functional methylthio head group combined with thermal annealing post gold source/drain electrode deposition to facilitate the interaction between SAM and electrode.     

Metastable Copper‐Phthalocyanine Single‐Crystal Nanowires and Their Use in Fabricating High‐Performance Field‐Effect Transistors

This paper describes a simple, vapor‐phase route for the synthesis of metastable α‐phase copper‐phthalocyanine (CuPc) single‐crystal nanowires through control of the growth temperature. The influence of the growth temperature on the crystal structures, morphology, and size of the CuPc nanostructures is explored using X‐ray diffraction (XRD), optical absorption, and transmission electron microscopy (TEM). α‐CuPc nanowires are successfully incorporated as active semiconductors in field‐effect transistors (FETs). Single nanowire devices exhibit carrier mobilities and current on/off ratios as high as 0.4 cm² V^?1 s^?1 and >10⁴, respectively.     

High‐Performance Phototransistors Based on Organic Microribbons Prepared by a Solution Self‐Assembly Process

Oligoarenes as an alternative group of promising semiconductors in organic optoelectronics have attracted much attention. However, high‐performance and low‐cost opto‐electrical devices based on linear asymmetric oligoarenes with nano/microstructures are still rarely studied because of difficulties both in synthesis and high‐quality nano/microstructure growth. Here, a novel linear asymmetric oligoarene 6‐methyl‐anthra[2,3‐b]benzo[d]thiophene (Me‐ABT) is synthesized and its high‐quality microribbons are grown by a solution process. The solution of Me‐ABT exhibits a moderate fluorescence quantum yield of 0.34, while the microribbons show a glaucous light emission. Phototransistors based on an individual Me‐ABT microribbon prepared by a solution‐phase self‐assembly process showed a high mobility of 1.66 cm² V^?1 s^?1, a large photoresponsivity of 12 000 A W^?1, and a photocurrent/dark‐current ratio of 6000 even under low light power conditions (30 µW cm^?2). The measured photoresponsivity of the devices is much higher than that of inorganic single‐crystal silicon thin film transistors. These studies should boost the development of the organic semiconductors with high‐quality microstructures for potential application in organic optoelectronics.     

Simultaneous Modification of Bottom‐Contact Electrode and Dielectric Surfaces for Organic Thin‐Film Transistors Through Single‐Component Spin‐Cast Monolayers

An efficient process is developed by spin‐coating a single‐component, self‐assembled monolayer (SAM) to simultaneously modify the bottom‐contact electrode and dielectric surfaces of organic thin‐film transistors (OTFTs). This effi cient interface modifi cation is achieved using n‐alkyl phosphonic acid based SAMs to prime silver bottom‐contacts and hafnium oxide (HfO₂) dielectrics in low‐voltage OTFTs. Surface characterization using near edge X‐ray absorption fi ne structure (NEXAFS) spectroscopy, X‐ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR‐FTIR) spectroscopy, atomic force microscopy (AFM), and spectroscopic ellipsometry suggest this process yields structurally well‐defi ned phosphonate SAMs on both metal and oxide surfaces. Rational selection of the alkyl length of the SAM leads to greatly enhanced performance for both n‐channel (C₆₀) and p‐channel (pentacene) based OTFTs. Specifi cally, SAMs of n‐octylphos‐phonic acid (OPA) provide both low‐contact resistance at the bottom‐contact electrodes and excellent interfacial properties for compact semiconductor grain growth with high carrier mobilities. OTFTs based on OPA modifi ed silver electrode/HfO₂ dielectric bottom‐contact structures can be operated using < 3V with low contact resistance (down to 700 Ohm‐cm), low subthreshold swing (as low as 75 mV dec^?1), high on/off current ratios of 107, and charge carrier mobilities as high as 4.6 and 0.8 cm² V^?1 s^?1, for C60 and pentacene, respectively. These results demonstrate that this is a simple and efficient process for improving the performance of bottom‐contact OTFTs.     

Network Structure Modification‐Enabled Hybrid Polymer Dielectric Film with Zirconia for the Stretchable Transistor Applications

Stretchable electronic devices should be enabled by the smart design of materials and architectures because their commercialization is limited by the tradeoff between stretchability and electrical performance limits. In this study, thin‐film transistors are fabricated using strategies that combine the unit process of a novel hybrid gate insulator and low‐temperature indium gallium tin oxide (IGTO) channel layer and a stress‐relief substrate structure. Novel hybrid dielectric films are synthesized and their molecular structural configurations are analyzed. These films consist of a polymer [poly(4‐vinylphenol‐co‐methylmethacrylate)], cross‐linkers having different binding structures [1,6‐bis(trimethoxysilyl)hexane (BTMSH), dodecyltrimethoxysilane, and poly(melamine‐co‐formaldehyde)], and an inorganic zirconia component (ZrO_x). The hybrid film with BTMSH cross‐linker and 0.2 M ZrO_x exhibits excellent insulating properties as well as mechanical stretchability. IGTO transistors fabricated on polyimide‐coated glass substrates are transferred to the rubber substrate to offer stretchability of the transistor pixelated thin‐film transistors. IGTO transistors fabricated on stretchable substrates using these strategies show promising electrical performance and mechanical durability. After 200 stretchability test cycles under uniaxial elongation of approximately 300%, the IGTO transistor still retains a high carrier mobility of 21.7 cm² V^?1 s^?1, a low sub‐threshold gate swing of 0.68 V decade^?1 and a high I_ON/OFF ratio of 2.0 × 10⁷.     

Layer‐by‐Layer Conjugated Extension of a Semiconducting Polymer for High‐Performance Organic Field‐Effect Transistor

A donor–acceptor (D–A) semiconducting copolymer, PDPP‐TVT‐29, comprising a diketopyrrolopyrrole (DPP) derivative with long, linear, space‐separated alkyl side‐chains and thiophene vinylene thiophene (TVT) for organic field‐effect transistors (OFETs) can form highly π‐conjugated structures with an edge‐on molecular orientation in an as‐spun film. In particular, the layer‐like conjugated film morphologies can be developed via short‐term thermal annealing above 150 °C for 10 min. The strong intermolecular interaction, originating from the fused DPP and D–A interaction, leads to the spontaneous self‐assembly of polymer chains within close proximity (with π‐overlap distance of 3.55 Å) and forms unexpectedly long‐range π‐conjugation, which is favorable for both intra‐ and intermolecular charge transport. Unlike intergranular nanorods in the as‐spun film, well‐conjugated layers in the 200 °C‐annealed film can yield more efficient charge‐transport pathways. The granular morphology of the as‐spun PDPP‐TVT‐29 film produces a field‐effect mobility (μ _FET) of 1.39 cm² V^?1 s^?1 in an OFET based on a polymer‐treated SiO₂ dielectric, while the 27‐Å‐step layered morphology in the 200 °C‐annealed films shows high μ _FET values of up to 3.7 cm² V^?1 s^?1.     

Self‐Assembled,Millimeter‐Sized TIPS‐Pentacene Spherulites Grown on Partially Crosslinked Polymer Gate Dielectric

Here, a highly crystalline and self‐assembled 6,13‐bis(triisopropylsilylethynyl) pentacene (TIPS‐Pentacene) thin films formed by simple spin‐coating for the fabrication of high‐performance solution‐processed organic field‐effect transistors (OFETs) are reported. Rather than using semiconducting organic small‐molecule–insulating polymer blends for an active layer of an organic transistor, TIPS‐Pentacene organic semiconductor is separately self‐assembled on partially crosslinked poly‐4‐vinylphenol:poly(melamine‐co‐formaldehyde) (PVP:PMF) gate dielectric, which results in a vertically segregated semiconductor‐dielectric film with millimeter‐sized spherulite‐crystalline morphology of TIPS‐Pentacene. The structural and electrical properties of TIPS‐Pentacene/PVP:PMF films have been studied using a combination of polarized optical microscopy, atomic force microscopy, 2D‐grazing incidence wide‐angle X‐ray scattering, and secondary ion mass spectrometry. It is finally demonstrated a high‐performance OFETs with a maximum hole mobility of 3.40 cm² V^?1 s^?1 which is, to the best of our knowledge, one of the highest mobility values for TIPS‐Pentacene OFETs fabricated using a conventional solution process. It is expected that this new deposition method would be applicable to other small molecular semiconductor–curable polymer gate dielectric systems for high‐performance organic electronic applications.     

Highly Stretchable,High‐Mobility,Free‐Standing All‐Organic Transistors Modulated by Solid‐State Elastomer Electrolytes

Highly stretchable, high‐mobility, and free‐standing coplanar‐type all‐organic transistors based on deformable solid‐state elastomer electrolytes are demonstrated using ionic thermoplastic polyurethane (i‐TPU), thereby showing high reliability under mechanical stimuli as well as low‐voltage operation. Unlike conventional ionic dielectrics, the i‐TPU electrolyte prepared herein has remarkable characteristics, i.e., a large specific capacitance of 5.5 µF cm^?2, despite the low weight ratio (20 wt%) of the ionic liquid, high transparency, and even stretchability. These i‐TPU‐based organic transistors exhibit a mobility as high as 7.9 cm² V^?1 s^?1, high bendability (R_c, radius of curvature: 7.2 mm), and good stretchability (60% tensile strain). Moreover, they are suitable for low‐voltage operation (V_DS = ?1.0 V, V_GS = ?2.5 V). In addition, the electrical characteristics such as mobility, on‐current, and threshold voltage are maintained even in the concave and convex bending state (bending tensile strain of ≈3.4%), respectively. Finally, free‐standing, fully stretchable, and semi‐transparent coplanar‐type all‐organic transistors can be fabricated by introducing a poly(3,4‐ethylenedioxythiophene):polystyrene sulfonic acid layer as source/drain and gate electrodes, thus achieving low‐voltage operation (V_DS = ?1.5 V, V_GS = ?2.5 V) and an even higher mobility of up to 17.8 cm² V^?1 s^?1. Moreover, these devices withstand stretching up to 80% tensile strain.     

Organic Thin‐Film Transistors: Simultaneous Modification of Bottom‐Contact Electrode and Dielectric Surfaces for Organic Thin‐Film Transistors Through Single‐Component Spin‐Cast Monolayers (Adv. Funct. Mater. 8/2011)

An efficient process is developed by spin‐coating a single‐component, self‐assembled monolayer (SAM) to simultaneously modify the bottom‐contact electrode and dielectric surfaces of organic thin‐film transistors (OTFTs). This effi cient interface modifi cation is achieved using n‐alkyl phosphonic acid based SAMs to prime silver bottom‐contacts and hafnium oxide (HfO₂) dielectrics in low‐voltage OTFTs. Surface characterization using near edge X‐ray absorption fi ne structure (NEXAFS) spectroscopy, X‐ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR‐FTIR) spectroscopy, atomic force microscopy (AFM), and spectroscopic ellipsometry suggest this process yields structurally well‐defi ned phosphonate SAMs on both metal and oxide surfaces. Rational selection of the alkyl length of the SAM leads to greatly enhanced performance for both n‐channel (C₆₀) and p‐channel (pentacene) based OTFTs. Specifi cally, SAMs of n‐octylphos‐phonic acid (OPA) provide both low‐contact resistance at the bottom‐contact electrodes and excellent interfacial properties for compact semiconductor grain growth with high carrier mobilities. OTFTs based on OPA modifi ed silver electrode/HfO₂ dielectric bottom‐contact structures can be operated using < 3V with low contact resistance (down to 700 Ohm‐cm), low subthreshold swing (as low as 75 mV dec^?1), high on/off current ratios of 107, and charge carrier mobilities as high as 4.6 and 0.8 cm² V^?1 s^?1, for C60 and pentacene, respectively. These results demonstrate that this is a simple and efficient process for improving the performance of bottom‐contact OTFTs.     

A Facile Method for the Growth of Organic Semiconductor Single Crystal Arrays on Polymer Dielectric toward Flexible Field‐Effect Transistors

Polymer dielectrics with intrinsic mechanical flexibility are considered as a key component for flexible organic field‐effect transistors (OFETs). However, it remains a challenge to fabricate highly aligned organic semiconductor single crystal (OSSC) arrays on the polymer dielectrics. Herein, for the first time, a facile and universal strategy, polar surface‐confined crystallization (PSCC), is proposed to grow highly aligned OSSC arrays on poly(4‐vinylphenol) (PVP) dielectric layer. The surface polarity of PVP is altered periodically with oxygen‐plasma treatment, enabling the preferential nucleation of organic crystals on the strong‐polarity regions. Moreover, a geometrical confinement effect of the patterned regions can also prevent multiple nucleation and misaligned molecular packing, enabling the highly aligned growth of OSSC arrays with uniform morphology and unitary crystallographic orientation. Using 2,7‐dioctyl[1]benzothieno[3,2‐b]benzothiophene (C8‐BTBT) as an example, highly aligned C8‐BTBT single crystal arrays with uniform molecular packing and crystal orientation are successfully fabricated on the PVP layer, which can guarantee their uniform electrical properties. OFETs made from the C8‐BTBT single crystal arrays on flexible substrates exhibit a mobility as high as 2.25 cm² V^?1 s^?1, which has surpassed the C8‐BTBT polycrystalline film‐based flexible devices. This work paves the way toward the fabrication of highly aligned OSSCs on polymer dielectrics for high‐performance, flexible organic devices.     

Self‐Assembly of Flexible Free‐Standing 3D Porous MoS2‐Reduced Graphene Oxide Structure for High‐Performance Lithium‐Ion Batteries

Flexible freestanding electrodes are highly desired to realize wearable/flexible batteries as required for the design and production of flexible electronic devices. Here, the excellent electrochemical performance and inherent flexibility of atomically thin 2D MoS₂ along with the self‐assembly properties of liquid crystalline graphene oxide (LCGO) dispersion are exploited to fabricate a porous anode for high‐performance lithium ion batteries. Flexible, free‐standing MoS₂–reduced graphene oxide (MG) film with a 3D porous structure is fabricated via a facile spontaneous self‐assembly process and subsequent freeze‐drying. This is the first report of a one‐pot self‐assembly, gelation, and subsequent reduction of MoS₂/LCGO composite to form a flexible, high performance electrode for charge storage. The gelation process occurs directly in the mixed dispersion of MoS₂ and LCGO nanosheets at a low temperature (70 °C) and normal atmosphere (1 atm). The MG film with 75 wt% of MoS₂ exhibits a high reversible capacity of 800 mAh g^?1 at a current density of 100 mA g^?1. It also demonstrates excellent rate capability, and excellent cycling stability with no capacity drop over 500 charge/discharge cycles at a current density of 400 mA g^?1.     

Self‐Organization of Ink‐jet‐Printed Triisopropylsilylethynyl Pentacene via Evaporation‐Induced Flows in a Drying Droplet

We have demonstrated the influence of evaporation‐induced flow in a single droplet on the crystalline microstructure and film morphology of an ink‐jet‐printed organic semiconductor, 6,13‐bis((triisopropylsilylethynyl) pentacene (TIPS_PEN), by varying the composition of the solvent mixture. The ringlike deposits induced by outward convective flow in the droplets have a randomly oriented crystalline structure. The addition of dichlorobenzene as an evaporation control agent results in a homogeneous film morphology due to slow evaporation, but the molecular orientation of the film is undesirable in that it is similar to that of the ring‐deposited films. However, self‐aligned TIPS_PEN crystals with highly ordered crystalline structures were successfully produced when dodecane was added. Dodecane has a high boiling point and a low surface tension, and its addition to the solvent results in a recirculation flow in the droplets that is induced by a Marangoni flow (surface‐tension‐driven flow), which arises during the drying processes in the direction opposite to the convective flow. The field‐effect transistors fabricated with these self‐aligned crystals via ink‐jet printing exhibit significantly improved performance with an average effective field‐effect mobility of 0.12 cm² V^–1 s^–1. These results demonstrate that with the choice of appropriate solvent ink‐jet printing is an excellent method for the production of organic semiconductor films with uniform morphology and desired molecular orientation for the direct‐write fabrication of high‐performance organic electronics.     

Electronic Transport Properties of Ensembles of Perylene‐Substituted Poly‐isocyanopeptide Arrays

The electronic transport properties of stacks of perylene‐bis(dicarboximide) (PDI) chromophores, covalently fixed to the side arms of rigid, helical polyisocyanopeptides, are studied using thin‐film transistors. In device architectures where the transistor channel lengths are somewhat greater than the average polymer chain length, carrier mobilities of order 10^?3 cm² V^?1 s^?1 at 350 K are found, which are limited by inter‐chain transport processes. The influence of π–π interactions on the material properties is studied by using PDIs with and without bulky substituents in the bay area. In order to attain a deeper understanding of both the electronic and the electronic‐transport properties of these systems, studies of self‐assembly on surfaces are combined with electronic characterization using Kelvin probe force microscopy, and also a theoretical study of electronic coupling. The use of a rigid polymer backbone as a scaffold to achieve a full control over the position and orientation of functional groups is of general applicability and interest in the design of building blocks for technologically important functional materials, as well as in more fundamental studies of chromophoric interactions.     

Bithienopyrroledione‐Based Copolymers,Versatile Semiconductors for Balanced Ambipolar Thin‐Film Transistors and Organic Solar Cells with V oc > 1 V

Conjugated polymer semiconductors P1 and P2 with bithienopyrroledione (bi‐TPD) as acceptor unit are synthesized. Their transistor and photovoltaic performances are investigated. Both polymers display high and balanced ambipolar transport behaviors in thin‐film transistors. P1‐ based devices show an electron mobility of 1.02 cm² V^?1 s^?1 and a hole mobility of 0.33 cm² V^?1 s^?1, one of the highest performance reported for ambipolar polymer transistors. The electron and hole mobilities of P2 transistors are 0.36 and 0.16 cm² V^?1 s^?1, respectively. The solar cells with PC₇₁BM as the electron acceptor and P1/P2 as the donor exhibit a high V _oc about 1.0 V, and a power conversion efficiency of 6.46% is observed for P1‐ based devices without any additives and/or post treatment. The high performance of P1 and P2 is attributed to their crystalline films and short π–π stacking distance (<3.5 Å). These results demonstrate (1) bi‐TPD is an excellent versatile electron‐deficient unit for polymer semiconductors and (2) bi‐TPD‐based polymer semiconductors have potential applications in organic transistors and organic solar cells.     

A Battery‐Less Arbitrary Motion Sensing System Using Magnetic Repulsion‐Based Self‐Powered Motion Sensors and Hybrid Nanogenerator

Self‐powered arbitrary motion sensors are in high demand in the field of autonomous controlled systems. In this work, a magnetic repulsion‐assisted self‐powered motion sensor is integrated with a hybrid nanogenerator (MRSMS–HNG) as a battery‐less arbitrary motion sensing system. The proposed device can efficiently detect the motion parameters of a moving object along any arbitrary direction and simultaneously convert low frequency (<5 Hz) vibrations into useful electricity. The MRSMS–HNG consists of a central magnet for the electromagnetic (EMG)–triboelectric (TENG) nanogenerator and four side magnets for motion sensors. Because all the magnets are aligned in the same magnetization direction, the repulsive force owing to the movement of the central magnet actuates the side magnets to achieve self‐powered arbitrary motion sensing. These self‐powered motion sensors exhibit a high sensitivity of 981.33 mV g^?1 under linear motion excitation and have a tilting angle sensitivity of 9.83 mV deg^?1. The proposed device can deliver peak powers of 27 mW and 56 µW from the EMG and TENG, respectively. By integrating the self‐powered motion sensors and hybrid nanogenerator on a single device, real‐time wireless transmission of motion sensor data to a smartphone is successfully demonstrated, thus realizing a battery‐less arbitrary motion‐sensing system for future autonomous control applications.     

High‐Mobility n‐Type Organic Transistors Based on a Crystallized Diketopyrrolopyrrole Derivative

A new high‐performing small molecule n‐channel semiconductor based on diketopyrrolopyrrole (DPP), 2,2′‐(5,5′‐(2,5‐bis(2‐ethylhexyl)‐3,6‐dioxo‐2,3,5,6‐tetrahydropyrrolo[3,4‐c]pyrrole‐1,4‐diyl)bis(thiophene‐5,2‐diyl))bis(methan‐1‐yl‐1‐ylidene)dimalononitrile (DPP‐T‐DCV), is successfully synthesized. The frontier molecular orbitals in this designed structure are elaborately tuned by introducing a strong electron‐accepting functionality (dicyanovinyl). The well‐defined lamellar structures of the crystals display a uniform terrace step height corresponding to a molecular monolayer in the solid‐state. As a result of this tuning and the remarkable crystallinity derived from the conformational planarity, organic field‐effect transistors (OFETs) based on dense‐packed solution‐processed single‐crystals of DPP‐T‐DCV exhibit an electron mobility (μ_e) up to 0.96 cm² V^?1 s^?1, one of the highest values yet obtained for DPP derivative‐based n‐channel OFETs. Polycrystalline OFETs show promise (with an μ_e up to 0.64 cm² V^?1 s^?1) for practical utility in organic device applications.     

Hydrocarbons‐Driven Crystallization of Polymer Semiconductors for Low‐Temperature Fabrication of High‐Performance Organic Field‐Effect Transistors

While many high‐performance polymer semiconductors are reported for organic field‐effect transistors (OFETs), most require a high‐temperature postdeposition annealing of channel semiconductors to achieve high performance. This negates the fundamental attribute of OFETs being a low‐cost alternative to conventional high‐cost silicon technologies. A facile solution process is developed through which high‐performance OFETs can be fabricated without thermal annealing. The process involves incorporation of an incompatible hydrocarbon binder or wax into the channel semiconductor composition to drive rapid phase separation and instantaneous crystallization of polymer semiconductor at room temperature. The resulting composite channel semiconductor film manifests a nano/microporous surface morphology with a continuous semiconductor nanowire network. OFET mobility of up to about 5 cm² V^?1 s^?1 and on/off ratio ≥ 10⁶ are attained. These are hitherto benchmark performance characteristics for room‐temperature, solution‐processed polymer OFETs, which are functionally useful for many impactful applications.