The Experts below are selected from a list of 162 Experts worldwide ranked by ideXlab platform

Jihua Chen - One of the best experts on this subject based on the ideXlab platform.

  • ultra low misorientation angle in Small Molecule Semiconductor polyethylene oxide blends for organic thin film transistors
    Journal of Polymer Research, 2020
    Co-Authors: Zhengran He, Ziyang Zhang, Sheng Bi, Kyeiwaa Asareyeboah, Jihua Chen
    Abstract:

    In this work, we report for the first time the use of a nonconjugated semicrystalline polymer as a film-forming agent to control the crystallization and tune the charge transport of solution-processed, Small-Molecule organic Semiconductors. When 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS pentacene) was demonstrated as a representative material to blend with polyethylene oxide (PEO) polymer, it crystallized into uniformly-aligned needles with reduced random orientation, enhanced long-range order and elevated areal coverage. Specifically, an ultra-low misorientation angle of 7.9° ± 3.5° was obtained with 10% PEO additive, beneficial for charge transport in the TIPS pentacene/PEO hybrid film. Bottom-gate, top-contact organic thin film transistors (OTFTs) based on TIPS pentacene/PEO mixture were found to show a field-effect mobility up to 2.5 × 10−2 cm2/Vs. This work may be universally applied to other organic Semiconductors to regulate their crystal formation, enhance film forming and improve device performance of OTFTs. It contributes to the utilization of flexible substrates for future-generation high-performance organic electronics.

  • Ultra-low misorientation angle in Small-Molecule Semiconductor/polyethylene oxide blends for organic thin film transistors
    Journal of Polymer Research, 2020
    Co-Authors: Zhengran He, Ziyang Zhang, Sheng Bi, Kyeiwaa Asare-yeboah, Jihua Chen
    Abstract:

    In this work, we report for the first time the use of a nonconjugated semicrystalline polymer as a film-forming agent to control the crystallization and tune the charge transport of solution-processed, Small-Molecule organic Semiconductors. When 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS pentacene) was demonstrated as a representative material to blend with polyethylene oxide (PEO) polymer, it crystallized into uniformly-aligned needles with reduced random orientation, enhanced long-range order and elevated areal coverage. Specifically, an ultra-low misorientation angle of 7.9° ± 3.5° was obtained with 10% PEO additive, beneficial for charge transport in the TIPS pentacene/PEO hybrid film. Bottom-gate, top-contact organic thin film transistors (OTFTs) based on TIPS pentacene/PEO mixture were found to show a field-effect mobility up to 2.5 × 10−2 cm2/Vs. This work may be universally applied to other organic Semiconductors to regulate their crystal formation, enhance film forming and improve device performance of OTFTs. It contributes to the utilization of flexible substrates for future-generation high-performance organic electronics.

  • conjugated polymer mediated polymorphism of a high performance Small Molecule organic Semiconductor with tuned intermolecular interactions enhanced long range order and charge transport
    Chemistry of Materials, 2013
    Co-Authors: Jihua Chen, Zhengran He, Ming Shao, Kai Xiao, Dawen Li, Bradley S Lokitz, D K Hensley, Michael S Kilbey, John E Anthony, Jong K Keum
    Abstract:

    We use 6,13-bis(triisopropylsilylethynyl)pentacene as a model Small Molecule organic Semiconductor and two conjugated polymer additives to demonstrate conjugated polymer-mediated polymorphism of a Small Molecule organic Semiconductor for the first time. The conjugated polymer additives, used with a slow solution crystallization approach, yield crystal structures that are not accessible by nonconjugated polymer additives and impart excellent long-range order. In both of the Small Molecule Semiconductor/conjugated polymer blends studied here, previously unreported polymorphs of a Small Molecule Semiconductor have been identified which also leads to improved charge transport in the absence of external alignment. These results open up a new exciting avenue to manipulate unit cell structure, long-range order, and charge transport of high performance, solution-processed, Small Molecule organic Semiconductors.

  • High-performance organic field-effect transistors with dielectric and active layers printed sequentially by ultrasonic spraying
    Journal of Materials Chemistry C, 2013
    Co-Authors: Ming Shao, Jihua Chen, Kai Xiao, Dawen Li, Jong K Keum, Ilia N. Ivanov, Gong Gu, William Durant, David B. Geohegan
    Abstract:

    High-performance organic field-effect transistors (OFETs) are reported with dielectric and active layers sequentially deposited by ultrasonic spray-printing. A cross-linkable insulator and a soluble Small Molecule Semiconductor are developed which are both printable and highly robust. Using plastic with pre-patterned indium tin oxide gate contacts as required for display applications, two different layers are sequentially spray-printed: the Semiconductor 6,13-bis(trisopropylsilylethynyl)pentacene (TIPS-PEN), and the insulator poly-4-vinylphenol (PVP). OFETs printed in ambient air with a bottom-gate/top-contact geometry are shown to achieve on/off ratios of >104 and mobilities up to 0.35 cm2 V−1 s−1. These rival the characteristics of the best solution-processable Small Molecule FETs fabricated by other processing methods such as drop casting and ink-jet printing.

Zhengran He - One of the best experts on this subject based on the ideXlab platform.

  • ultra low misorientation angle in Small Molecule Semiconductor polyethylene oxide blends for organic thin film transistors
    Journal of Polymer Research, 2020
    Co-Authors: Zhengran He, Ziyang Zhang, Sheng Bi, Kyeiwaa Asareyeboah, Jihua Chen
    Abstract:

    In this work, we report for the first time the use of a nonconjugated semicrystalline polymer as a film-forming agent to control the crystallization and tune the charge transport of solution-processed, Small-Molecule organic Semiconductors. When 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS pentacene) was demonstrated as a representative material to blend with polyethylene oxide (PEO) polymer, it crystallized into uniformly-aligned needles with reduced random orientation, enhanced long-range order and elevated areal coverage. Specifically, an ultra-low misorientation angle of 7.9° ± 3.5° was obtained with 10% PEO additive, beneficial for charge transport in the TIPS pentacene/PEO hybrid film. Bottom-gate, top-contact organic thin film transistors (OTFTs) based on TIPS pentacene/PEO mixture were found to show a field-effect mobility up to 2.5 × 10−2 cm2/Vs. This work may be universally applied to other organic Semiconductors to regulate their crystal formation, enhance film forming and improve device performance of OTFTs. It contributes to the utilization of flexible substrates for future-generation high-performance organic electronics.

  • Ultra-low misorientation angle in Small-Molecule Semiconductor/polyethylene oxide blends for organic thin film transistors
    Journal of Polymer Research, 2020
    Co-Authors: Zhengran He, Ziyang Zhang, Sheng Bi, Kyeiwaa Asare-yeboah, Jihua Chen
    Abstract:

    In this work, we report for the first time the use of a nonconjugated semicrystalline polymer as a film-forming agent to control the crystallization and tune the charge transport of solution-processed, Small-Molecule organic Semiconductors. When 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS pentacene) was demonstrated as a representative material to blend with polyethylene oxide (PEO) polymer, it crystallized into uniformly-aligned needles with reduced random orientation, enhanced long-range order and elevated areal coverage. Specifically, an ultra-low misorientation angle of 7.9° ± 3.5° was obtained with 10% PEO additive, beneficial for charge transport in the TIPS pentacene/PEO hybrid film. Bottom-gate, top-contact organic thin film transistors (OTFTs) based on TIPS pentacene/PEO mixture were found to show a field-effect mobility up to 2.5 × 10−2 cm2/Vs. This work may be universally applied to other organic Semiconductors to regulate their crystal formation, enhance film forming and improve device performance of OTFTs. It contributes to the utilization of flexible substrates for future-generation high-performance organic electronics.

  • polyacrylate polymer assisted crystallization improved charge transport and performance consistency for solution processable Small Molecule Semiconductor based organic thin film transistors
    Journal of Science: Advanced Materials and Devices, 2019
    Co-Authors: Zhengran He, Ziyang Zhang, Sheng Bi
    Abstract:

    Abstract In this study, we report on an effective approach to modulate crystallization, control charge transport and enhance performance consistency of Small-Molecule Semiconductor based organic thin film transistors (OTFTs) with the addition of a polyacrylate polymer additive poly(2-ethylhexyl acrylate) (P2EHA). 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) was used as a benchmark Semiconductor to blend with the P2EHA additive, leading to a vertical phase separation between these two components. The resultant TIPS pentacene film exhibited greatly reduced crystal misorientation, enlarged grain width and enhanced film coverage. Bottom-gate, bottom-contact OTFTs based on the TIPS pentacene/P2EHA blends were fabricated and showed an increased average hole mobility of 0.317 ± 0.047 cm2/V, as well as a performance consistency factor of 6.72, which is defined as the ratio of the average hole mobility to the standard deviation of mobility. Notably, it leads to a 10-fold and 7-fold enhancement of average mobility and performance consistency as compared to the pristine TIPS pentacene OTFTs. This great improvement of device performance can be attributed to the reduced crystal misorientation, less defects and trap centers at the grain boundaries as a result of the enlarged grain width, as well as increased film coverage, due to the addition of the P2EHA polyacrylate polymer additive.

  • poly α methylstyrene polymer and Small Molecule Semiconductor blend with reduced crystal misorientation for organic thin film transistors
    Journal of Materials Science: Materials in Electronics, 2019
    Co-Authors: Zhengran He, Ziyang Zhang, Kyeiwaa Asareyeboah, Sheng Bi
    Abstract:

    The electrical performance of solution-processed, Small-Molecule organic Semiconductors is largely restricted by their severe charge carrier mobility variations. In this work, we demonstrate an effective method to reduce such variations of the Semiconductor mobilities and improve the performance consistency of organic thin film transistors (OTFTs) by adding poly(α-methylstyrene) (PαMS) as a polymer additive. By using 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) as an example, we found that while pristine TIPS pentacene film exhibited random crystal orientation and large film gaps, the addition of PαMS polymer promoted the growth of Semiconductor crystals, which formed uniformly aligned needles with significantly improved orientation and coverage within the channel regions. An ultra-low misorientation angle of 2.2° ± 1° was obtained from TIPS pentacene/PαMS blend film, which is a 20-fold reduction as compared to pristine TIPS pentacene. Bottom-gate, top-contact OTFTs with TIPS pentacene crystals aligned perpendicularly from source to drain contact electrodes demonstrated a hole mobility of up to 0.26 cm2/V s, as well a 6-fold enhancement of average mobility as compared to the pristine TIPS pentacene based counterparts. Notably, the addition of PαMS led to a performance consistency factor of 3.35, as defined by the ratio of the average mobility to standard deviation, implying a great reduction of charge carrier mobility variations. The improvement of electrical performance of OTFTs can be attributed to the combined outcome of crystal rigid alignment, extended long-range order, and almost full coverage of charge transport channel.

  • conjugated polymer mediated polymorphism of a high performance Small Molecule organic Semiconductor with tuned intermolecular interactions enhanced long range order and charge transport
    Chemistry of Materials, 2013
    Co-Authors: Jihua Chen, Zhengran He, Ming Shao, Kai Xiao, Dawen Li, Bradley S Lokitz, D K Hensley, Michael S Kilbey, John E Anthony, Jong K Keum
    Abstract:

    We use 6,13-bis(triisopropylsilylethynyl)pentacene as a model Small Molecule organic Semiconductor and two conjugated polymer additives to demonstrate conjugated polymer-mediated polymorphism of a Small Molecule organic Semiconductor for the first time. The conjugated polymer additives, used with a slow solution crystallization approach, yield crystal structures that are not accessible by nonconjugated polymer additives and impart excellent long-range order. In both of the Small Molecule Semiconductor/conjugated polymer blends studied here, previously unreported polymorphs of a Small Molecule Semiconductor have been identified which also leads to improved charge transport in the absence of external alignment. These results open up a new exciting avenue to manipulate unit cell structure, long-range order, and charge transport of high performance, solution-processed, Small Molecule organic Semiconductors.

Klaus Kern - One of the best experts on this subject based on the ideXlab platform.

  • high mobility organic thin film transistors based on a Small Molecule Semiconductor deposited in vacuum and by solution shearing
    Organic Electronics, 2013
    Co-Authors: R Hofmockel, Ulrike Kraft, Kazuo Takimiya, R. Rödel, Ute Zschieschang, Nis Hauke Hansen, Matthias Stolte, Frank Wurthner, Klaus Kern
    Abstract:

    The Small-Molecule organic Semiconductor 2,9-di-decyl-dinaphtho-[2,3-b: 2',3'-f]-thieno[3,2-b]-thiophene (C-10-DNTT) was used to fabricate bottom-gate, top-contact thin-film transistors (TFTs) in which the Semiconductor layer was prepared either by vacuum deposition or by solution shearing. The maximum effective charge-carrier mobility of TFTs with vacuum-deposited C-10-DNTT is 8.5 cm(2)/V s for a nominal Semiconductor thickness of 10 nm and a substrate temperature during the Semiconductor deposition of 80 degrees C. Scanning electron microscopy analysis reveals the growth of Small, isolated islands that begin to coalesce into a flat conducting layer when the nominal thickness exceeds 4 nm. The morphology of the vacuum-deposited Semiconductor layers is dominated by tall lamellae that are formed during the deposition, except at very high substrate temperatures. Atomic force microscopy and X-ray diffraction measurements indicate that the C-10-DNTT Molecules stand approximately upright with respect to the substrate surface, both in the flat conducting layer near the surface and within the lamellae. Using the transmission line method on TFTs with channel lengths ranging from 10 to 100 mu m, a relatively Small contact resistance of 0.33 k Omega cm was determined. TFTs with the C-10-DNTT layer prepared by solution shearing exhibit a pronounced anisotropy of the electrical performance: TFTs with the channel oriented parallel to the shearing direction have an average carrier mobility of (2.8 +/- 0.3) cm(2)/V s, while TFTs with the channel oriented perpendicular to the shearing direction have a somewhat Smaller average mobility of (1.3 +/- 0.1) cm(2)/V s. (C) 2013 Elsevier B.V. All rights reserved.

Sheng Bi - One of the best experts on this subject based on the ideXlab platform.

  • ultra low misorientation angle in Small Molecule Semiconductor polyethylene oxide blends for organic thin film transistors
    Journal of Polymer Research, 2020
    Co-Authors: Zhengran He, Ziyang Zhang, Sheng Bi, Kyeiwaa Asareyeboah, Jihua Chen
    Abstract:

    In this work, we report for the first time the use of a nonconjugated semicrystalline polymer as a film-forming agent to control the crystallization and tune the charge transport of solution-processed, Small-Molecule organic Semiconductors. When 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS pentacene) was demonstrated as a representative material to blend with polyethylene oxide (PEO) polymer, it crystallized into uniformly-aligned needles with reduced random orientation, enhanced long-range order and elevated areal coverage. Specifically, an ultra-low misorientation angle of 7.9° ± 3.5° was obtained with 10% PEO additive, beneficial for charge transport in the TIPS pentacene/PEO hybrid film. Bottom-gate, top-contact organic thin film transistors (OTFTs) based on TIPS pentacene/PEO mixture were found to show a field-effect mobility up to 2.5 × 10−2 cm2/Vs. This work may be universally applied to other organic Semiconductors to regulate their crystal formation, enhance film forming and improve device performance of OTFTs. It contributes to the utilization of flexible substrates for future-generation high-performance organic electronics.

  • Ultra-low misorientation angle in Small-Molecule Semiconductor/polyethylene oxide blends for organic thin film transistors
    Journal of Polymer Research, 2020
    Co-Authors: Zhengran He, Ziyang Zhang, Sheng Bi, Kyeiwaa Asare-yeboah, Jihua Chen
    Abstract:

    In this work, we report for the first time the use of a nonconjugated semicrystalline polymer as a film-forming agent to control the crystallization and tune the charge transport of solution-processed, Small-Molecule organic Semiconductors. When 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS pentacene) was demonstrated as a representative material to blend with polyethylene oxide (PEO) polymer, it crystallized into uniformly-aligned needles with reduced random orientation, enhanced long-range order and elevated areal coverage. Specifically, an ultra-low misorientation angle of 7.9° ± 3.5° was obtained with 10% PEO additive, beneficial for charge transport in the TIPS pentacene/PEO hybrid film. Bottom-gate, top-contact organic thin film transistors (OTFTs) based on TIPS pentacene/PEO mixture were found to show a field-effect mobility up to 2.5 × 10−2 cm2/Vs. This work may be universally applied to other organic Semiconductors to regulate their crystal formation, enhance film forming and improve device performance of OTFTs. It contributes to the utilization of flexible substrates for future-generation high-performance organic electronics.

  • polyacrylate polymer assisted crystallization improved charge transport and performance consistency for solution processable Small Molecule Semiconductor based organic thin film transistors
    Journal of Science: Advanced Materials and Devices, 2019
    Co-Authors: Zhengran He, Ziyang Zhang, Sheng Bi
    Abstract:

    Abstract In this study, we report on an effective approach to modulate crystallization, control charge transport and enhance performance consistency of Small-Molecule Semiconductor based organic thin film transistors (OTFTs) with the addition of a polyacrylate polymer additive poly(2-ethylhexyl acrylate) (P2EHA). 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) was used as a benchmark Semiconductor to blend with the P2EHA additive, leading to a vertical phase separation between these two components. The resultant TIPS pentacene film exhibited greatly reduced crystal misorientation, enlarged grain width and enhanced film coverage. Bottom-gate, bottom-contact OTFTs based on the TIPS pentacene/P2EHA blends were fabricated and showed an increased average hole mobility of 0.317 ± 0.047 cm2/V, as well as a performance consistency factor of 6.72, which is defined as the ratio of the average hole mobility to the standard deviation of mobility. Notably, it leads to a 10-fold and 7-fold enhancement of average mobility and performance consistency as compared to the pristine TIPS pentacene OTFTs. This great improvement of device performance can be attributed to the reduced crystal misorientation, less defects and trap centers at the grain boundaries as a result of the enlarged grain width, as well as increased film coverage, due to the addition of the P2EHA polyacrylate polymer additive.

  • poly α methylstyrene polymer and Small Molecule Semiconductor blend with reduced crystal misorientation for organic thin film transistors
    Journal of Materials Science: Materials in Electronics, 2019
    Co-Authors: Zhengran He, Ziyang Zhang, Kyeiwaa Asareyeboah, Sheng Bi
    Abstract:

    The electrical performance of solution-processed, Small-Molecule organic Semiconductors is largely restricted by their severe charge carrier mobility variations. In this work, we demonstrate an effective method to reduce such variations of the Semiconductor mobilities and improve the performance consistency of organic thin film transistors (OTFTs) by adding poly(α-methylstyrene) (PαMS) as a polymer additive. By using 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) as an example, we found that while pristine TIPS pentacene film exhibited random crystal orientation and large film gaps, the addition of PαMS polymer promoted the growth of Semiconductor crystals, which formed uniformly aligned needles with significantly improved orientation and coverage within the channel regions. An ultra-low misorientation angle of 2.2° ± 1° was obtained from TIPS pentacene/PαMS blend film, which is a 20-fold reduction as compared to pristine TIPS pentacene. Bottom-gate, top-contact OTFTs with TIPS pentacene crystals aligned perpendicularly from source to drain contact electrodes demonstrated a hole mobility of up to 0.26 cm2/V s, as well a 6-fold enhancement of average mobility as compared to the pristine TIPS pentacene based counterparts. Notably, the addition of PαMS led to a performance consistency factor of 3.35, as defined by the ratio of the average mobility to standard deviation, implying a great reduction of charge carrier mobility variations. The improvement of electrical performance of OTFTs can be attributed to the combined outcome of crystal rigid alignment, extended long-range order, and almost full coverage of charge transport channel.

Ute Zschieschang - One of the best experts on this subject based on the ideXlab platform.

  • Low-voltage organic transistors with steep subthreshold slope fabricated on commercially available paper
    Organic Electronics, 2015
    Co-Authors: Ute Zschieschang, Hagen Klauk
    Abstract:

    Abstract Organic thin-film transistors were fabricated directly on the surface of commercially available cleanroom paper using the vacuum-deposited Small-Molecule Semiconductor dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT). A thin, high-capacitance gate dielectric that allows the TFTs to be operated with low voltages of 2 V was employed. The TFTs have a charge-carrier mobility of 1.6 cm2/Vs, an on/off current ratio of 106, and a subthreshold slope of 90 mV/decade. In addition, the TFTs also display a very large differential output resistance, which is an important requirement for applications in analog circuits and active-matrix displays.

  • high mobility organic thin film transistors based on a Small Molecule Semiconductor deposited in vacuum and by solution shearing
    Organic Electronics, 2013
    Co-Authors: R Hofmockel, Ulrike Kraft, Kazuo Takimiya, R. Rödel, Ute Zschieschang, Nis Hauke Hansen, Matthias Stolte, Frank Wurthner, Klaus Kern
    Abstract:

    The Small-Molecule organic Semiconductor 2,9-di-decyl-dinaphtho-[2,3-b: 2',3'-f]-thieno[3,2-b]-thiophene (C-10-DNTT) was used to fabricate bottom-gate, top-contact thin-film transistors (TFTs) in which the Semiconductor layer was prepared either by vacuum deposition or by solution shearing. The maximum effective charge-carrier mobility of TFTs with vacuum-deposited C-10-DNTT is 8.5 cm(2)/V s for a nominal Semiconductor thickness of 10 nm and a substrate temperature during the Semiconductor deposition of 80 degrees C. Scanning electron microscopy analysis reveals the growth of Small, isolated islands that begin to coalesce into a flat conducting layer when the nominal thickness exceeds 4 nm. The morphology of the vacuum-deposited Semiconductor layers is dominated by tall lamellae that are formed during the deposition, except at very high substrate temperatures. Atomic force microscopy and X-ray diffraction measurements indicate that the C-10-DNTT Molecules stand approximately upright with respect to the substrate surface, both in the flat conducting layer near the surface and within the lamellae. Using the transmission line method on TFTs with channel lengths ranging from 10 to 100 mu m, a relatively Small contact resistance of 0.33 k Omega cm was determined. TFTs with the C-10-DNTT layer prepared by solution shearing exhibit a pronounced anisotropy of the electrical performance: TFTs with the channel oriented parallel to the shearing direction have an average carrier mobility of (2.8 +/- 0.3) cm(2)/V s, while TFTs with the channel oriented perpendicular to the shearing direction have a somewhat Smaller average mobility of (1.3 +/- 0.1) cm(2)/V s. (C) 2013 Elsevier B.V. All rights reserved.

  • Megahertz operation of flexible low-voltage organic thin-film transistors
    Organic Electronics, 2013
    Co-Authors: Ute Zschieschang, Ulrike Kraft, Myeong Jin Kang, Tarek Zaki, Jörg Butschke, Florian Letzkus, R Hofmockel, Kazuo Takimiya, R. Rödel, Harald Richter
    Abstract:

    Abstract Bottom-gate, top-contact (inverted staggered) organic thin-film transistors with a channel length of 1 μm have been fabricated on flexible plastic substrates using the vacuum-deposited Small-Molecule Semiconductor 2,9-didecyl-dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (C10-DNTT). The transistors have an effective field-effect mobility of 1.2 cm2/V s, an on/off ratio of 107, a width-normalized transconductance of 1.2 S/m (with a standard deviation of 6%), and a signal propagation delay (measured in 11-stage ring oscillators) of 420 ns per stage at a supply voltage of 3 V. To our knowledge, this is the first time that megahertz operation has been achieved in flexible organic transistors at supply voltages of less than 10 V.

  • Megahertz operation of flexible low-voltage organic thin-film transistors
    Organic Electronics: physics materials applications, 2013
    Co-Authors: Ute Zschieschang, Ulrike Kraft, Myeong Jin Kang, Tarek Zaki, Jörg Butschke, Florian Letzkus, R Hofmockel, Kazuo Takimiya, R. Rödel, Harald Richter
    Abstract:

    Bottom-gate, top-contact (inverted staggered) organic thin-film transistors with a channel length of 1 μm have been fabricated on flexible plastic substrates using the vacuum-deposited Small-Molecule Semiconductor 2,9-didecyl-dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (C10-DNTT). The transistors have an effective field-effect mobility of 1.2 cm2/V s, an on/off ratio of 107, a width-normalized transconductance of 1.2 S/m (with a standard deviation of 6%), and a signal propagation delay (measured in 11-stage ring oscillators) of 420 ns per stage at a supply voltage of 3 V. To our knowledge, this is the first time that megahertz operation has been achieved in flexible organic transistors at supply voltages of less than 10 V. © 2013 Elsevier B.V. All rights reserved.