Charge transport enhancement via air-mediated self-organization in polymer semiconductors

ABSTRACTAir-mediated molecular ordering in self-organized polymer semiconductors of regioregular poly(3-hexylthiophene) (P3HT) and poly[(9,9′-dioctylfluorenyl-2,7-diyl)-(2,2′-bithiophene-5,5′-diyl)] (F8T2) was investigated using organic field-effect transistors (OFETs) fabricated by transfer-printing using poly(dimethylsiloxane) stamps with various surface energies. OFET measurements revealed that the charge transport in the polymer semiconductors via the air interface layer was better than that via the substrate interface layer. The results indicated that the formation of a highly ordered microstructure at the polymer/air interface through air-mediated self-organization occurs in many polymer semiconductors. This air-mediated self-organization was weaker than substrate-mediated self-organization, whose influence appeared in OFETs with thin semiconductor films.

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Charge transport in ambipolar pentacene thin film transistors

MRS Proceedings ◽

10.1557/opl.2011.239 ◽

2011 ◽

Vol 1286 ◽

Author(s):

Ronak Rahimi ◽

D. Korakakis

Keyword(s):

Charge Transport ◽

Active Layer ◽

Transition Point ◽

Conduction Mechanism ◽

Field Effect Transistors ◽

Interface Layer ◽

Oxide Semiconductor ◽

Organic Transistors ◽

Tunneling Model ◽

Transport Characteristic

ABSTRACTAmbipolar organic transistors are technologically interesting because of their potential applications in light-emitting field-effect transistors [1] and complementary-metal-oxide-semiconductor (CMOS) devices by providing ease of design, low cost of fabrication, and flexibility [2]. Although common organic semiconductors show either n- or p-type charge transport characteristic, organic transistors with ambipolar characteristics have been reported recently. In this work, we show that ambipolar transport can be achieved within a single transistor channel using LiF gate dielectric in the transistors with pentacene active layer. This ambipolar behavior can be controlled by the applied source-drain and gate biases. It was found that at low source-drain biases multistep hopping is the dominant conduction mechanism, while in high voltage regimes I-V data fits in Fowler-Nordheim (F-N) tunneling model. From the slope of the F-N plots, the dependency between field enhancement factor and the transition point in conduction mechanism upon gate bias has been extracted. The transition points show more dependency on gate voltage for negative biases compared to the positive biases. While sweeping negative gate voltages from -5 to -20 V, the source-drain voltages change from about 27 to 17 V. On the other hand, for positive gate voltages from 5 to 20 V, the value of the transition point stays at approximately 36 V. In order to further understand the transport mechanisms, new structures with an interface layer between dielectric and active layer have been fabricated and characterized. As expected, a significant decrease in the amount of the source-drain current has been observed after introducing the interface layer.

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Highly stretchable polymer semiconductor films through the nanoconfinement effect

Science ◽

10.1126/science.aah4496 ◽

2017 ◽

Vol 355 (6320) ◽

pp. 59-64 ◽

Cited By ~ 437

Author(s):

Jie Xu ◽

Sihong Wang ◽

Ging-Ji Nathan Wang ◽

Chenxin Zhu ◽

Shaochuan Luo ◽

...

Keyword(s):

Charge Transport ◽

Light Emitting Diode ◽

Wearable Electronics ◽

Semiconductor Films ◽

Light Emitting ◽

Polymer Semiconductors ◽

Polymer Semiconductor ◽

Highly Stretchable ◽

Transport Mobility ◽

Semiconducting Film

Soft and conformable wearable electronics require stretchable semiconductors, but existing ones typically sacrifice charge transport mobility to achieve stretchability. We explore a concept based on the nanoconfinement of polymers to substantially improve the stretchability of polymer semiconductors, without affecting charge transport mobility. The increased polymer chain dynamics under nanoconfinement significantly reduces the modulus of the conjugated polymer and largely delays the onset of crack formation under strain. As a result, our fabricated semiconducting film can be stretched up to 100% strain without affecting mobility, retaining values comparable to that of amorphous silicon. The fully stretchable transistors exhibit high biaxial stretchability with minimal change in on current even when poked with a sharp object. We demonstrate a skinlike finger-wearable driver for a light-emitting diode.

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Transfer printing of gate dielectric and carrier doping with poly(vinyl-alcohol) coating to fabricate top-gate molybdenum disulfide field-effect transistors

Japanese Journal of Applied Physics ◽

10.35848/1347-4065/abc6be ◽

2020 ◽

Vol 59 (12) ◽

pp. 120903

Author(s):

Takamasa Kawanago ◽

Takahiro Matsuzaki ◽

Shunri Oda

Keyword(s):

Molybdenum Disulfide ◽

Vinyl Alcohol ◽

Field Effect ◽

Gate Dielectric ◽

Field Effect Transistors ◽

Poly Vinyl Alcohol ◽

Transfer Printing ◽

Carrier Doping

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Self-replication of a quantum artificial organism driven by single-photon pulses

Scientific Reports ◽

10.1038/s41598-021-96048-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Daniel Valente

Keyword(s):

Self Assembly ◽

Artificial Life ◽

Single Photon ◽

Self Organization ◽

Physical Systems ◽

Self Organized ◽

Living Organisms ◽

A Chain ◽

Thermodynamic Mechanism ◽

Self Replication

AbstractImitating the transition from inanimate to living matter is a longstanding challenge. Artificial life has achieved computer programs that self-replicate, mutate, compete and evolve, but lacks self-organized hardwares akin to the self-assembly of the first living cells. Nonequilibrium thermodynamics has achieved lifelike self-organization in diverse physical systems, but has not yet met the open-ended evolution of living organisms. Here, I look for the emergence of an artificial-life code in a nonequilibrium physical system undergoing self-organization. I devise a toy model where the onset of self-replication of a quantum artificial organism (a chain of lambda systems) is owing to single-photon pulses added to a zero-temperature environment. I find that spontaneous mutations during self-replication are unavoidable in this model, due to rare but finite absorption of off-resonant photons. I also show that the replication probability is proportional to the absorbed work from the photon, thereby fulfilling a dissipative adaptation (a thermodynamic mechanism underlying lifelike self-organization). These results hint at self-replication as the scenario where dissipative adaptation (pointing towards convergence) coexists with open-ended evolution (pointing towards divergence).

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Balanced Ambipolar Charge Transport in Phenacene/Perylene Heterojunction-Based Organic Field-Effect Transistors

ACS Applied Materials & Interfaces ◽

10.1021/acsami.0c20140 ◽

2021 ◽

Vol 13 (7) ◽

pp. 8631-8642

Author(s):

Tomoya Taguchi ◽

Fabio Chiarella ◽

Mario Barra ◽

Federico Chianese ◽

Yoshihiro Kubozono ◽

...

Keyword(s):

Charge Transport ◽

Field Effect ◽

Field Effect Transistors ◽

Organic Field Effect Transistors

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Travelling colourful patterns in self-organized cellulose-based liquid crystalline structures

Communications Materials ◽

10.1038/s43246-021-00182-7 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Pedro E. S. Silva ◽

Ricardo Chagas ◽

Susete N. Fernandes ◽

Pawel Pieranski ◽

Robin L. B. Selinger ◽

...

Keyword(s):

Simple Model ◽

Temporal Variation ◽

Liquid Crystalline ◽

Diffusion Mechanism ◽

Reaction Diffusion ◽

Self Organization ◽

Spatial And Temporal Variation ◽

Living Matter ◽

Equilibrium Conditions ◽

Self Organized

AbstractCellulose-based systems are useful for many applications. However, the issue of self-organization under non-equilibrium conditions, which is ubiquitous in living matter, has scarcely been addressed in cellulose-based materials. Here, we show that quasi-2D preparations of a lyotropic cellulose-based cholesteric mesophase display travelling colourful patterns, which are generated by a chemical reaction-diffusion mechanism being simultaneous with the evaporation of solvents at the boundaries. These patterns involve spatial and temporal variation in the amplitude and sign of the helix´s pitch. We propose a simple model, based on a reaction-diffusion mechanism, which simulates the observed spatiotemporal colour behaviour.

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Self-Organized Criticality on Twitter: Phenomenological Theory and Empirical Investigation Based on Data Analysis Results

Complexity ◽

10.1155/2019/8750643 ◽

2019 ◽

Vol 2019 ◽

pp. 1-16 ◽

Cited By ~ 3

Author(s):

Andrey Dmitriev ◽

Victor Dmitriev ◽

Stepan Balybin

Keyword(s):

Time Series ◽

Critical State ◽

Empirical Investigation ◽

Phenomenological Theory ◽

Self Organization ◽

Protest Movements ◽

Self Organized ◽

Self Organized Criticality ◽

Stochastic Sources ◽

Adiabatic Mode

Recently, there has been an increasing number of empirical evidence supporting the hypothesis that spread of avalanches of microposts on social networks, such as Twitter, is associated with some sociopolitical events. Typical examples of such events are political elections and protest movements. Inspired by this phenomenon, we built a phenomenological model that describes Twitter’s self-organization in a critical state. An external manifestation of this condition is the spread of avalanches of microposts on the network. The model is based on a fractional three-parameter self-organization scheme with stochastic sources. It is shown that the adiabatic mode of self-organization in a critical state is determined by the intensive coordinated action of a relatively small number of network users. To identify the critical states of the network and to verify the model, we have proposed a spectrum of three scaling indicators of the observed time series of microposts.

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