Possible Deviation from the well-known Threshold Behavior of Field-Effect Doping Phenomenon in Extremely Thin Organic Semiconductor Layer

Organic semiconducting material based sensors have been used for various environmental applications. Organic field effect transistors (OFETs) also find their applications in explosive vapor detection and total ionizing radiation dose determination. OFETs using poly 3-hexylthiophene (P3HT), a p-type organic semiconductor material and CuII tetraphenylporphyrin ( CuTPP ) composite as their active material were investigated as sensors for detection of various nitro-based explosive vapors with greater than parts per billion sensitivity range. Significant changes, suitable for sensor response, were observed in ON current (Ion) and transconductance (gm) extracted from electrical characteristics of the OFET after exposure to vapors of various explosive compounds. However, a similar device response was not observed to strong oxidizing agents such as benzoquinone (BQ) and benzophenone (BP). Also, the use of organic semiconducting material sensors for determining total ionizing radiation dose was studied, wherein the conductivity of the material was measured as a function of total ionizing radiation dose. An organic semiconducting material resistor was exposed to γ-radiation and it was observed that the change in resistance was proportional to the ionizing radiation dose. Changes in various parameters extracted from electrical characteristics of the OFET after γ-radiation exposure resulted in an improved sensitivity. To protect the organic semiconductor layer from the degradation in the ambient the sensors were passivated with a thin layer of silicon nitride.

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Exploring the Critical Thickness of Organic Semiconductor Layer for Enhanced Piezoresistive Sensitivity in Field-Effect Transistor Sensors

Materials ◽

10.3390/ma13071583 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1583 ◽

Cited By ~ 4

Author(s):

Damien Thuau ◽

Katherine Begley ◽

Rishat Dilmurat ◽

Abduleziz Ablat ◽

Guillaume Wantz ◽

...

Keyword(s):

Organic Semiconductors ◽

Organic Semiconductor ◽

Field Effect ◽

High Performance ◽

Critical Thickness ◽

Field Effect Transistors ◽

Mechanical Strain ◽

Semiconductor Layer ◽

Organic Field Effect Transistors ◽

P Type

Organic semiconductors (OSCs) are promising transducer materials when applied in organic field-effect transistors (OFETs) taking advantage of their electrical properties which highly depend on the morphology of the semiconducting film. In this work, the effects of OSC thickness (ranging from 5 to 15 nm) on the piezoresistive sensitivity of a high-performance p-type organic semiconductor, namely dinaphtho [2,3-b:2,3-f] thieno [3,2–b] thiophene (DNTT), were investigated. Critical thickness of 6 nm thin film DNTT, thickness corresponding to the appearance of charge carrier percolation paths in the material, was demonstrated to be highly sensitive to mechanical strain. Gauge factors (GFs) of 42 ± 5 and −31 ± 6 were measured from the variation of output currents of 6 nm thick DNTT-based OFETs engineered on top of polymer cantilevers in response to compressive and tensile strain, respectively. The relationship between the morphologies of the different thin films and their corresponding piezoresistive sensitivities was discussed.

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Mercury-Mediated Organic Semiconductor Surface Doping Monitored by Electrolyte-Gated Field-Effect Transistors

Advanced Functional Materials ◽

10.1002/adfm.201703899 ◽

2017 ◽

Vol 27 (46) ◽

pp. 1703899 ◽

Cited By ~ 7

Author(s):

Qiaoming Zhang ◽

Francesca Leonardi ◽

Stefano Casalini ◽

Marta Mas-Torrent

Keyword(s):

Organic Semiconductor ◽

Field Effect ◽

Field Effect Transistors ◽

Semiconductor Surface ◽

Surface Doping

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Hysteresis Behavior of the Donor–Acceptor-Type Ambipolar Semiconductor for Non-Volatile Memory Applications

Micromachines ◽

10.3390/mi12030301 ◽

2021 ◽

Vol 12 (3) ◽

pp. 301

Author(s):

Young Jin Choi ◽

Jihyun Kim ◽

Min Je Kim ◽

Hwa Sook Ryu ◽

Han Young Woo ◽

...

Keyword(s):

Organic Semiconductor ◽

Field Effect ◽

Field Effect Transistor ◽

Memory Device ◽

Non Volatile Memory ◽

Device Applications ◽

Donor Acceptor ◽

Effect Transistor ◽

Volatile Memory ◽

Memory Applications

Donor–acceptor-type organic semiconductor molecules are of great interest for potential organic field-effect transistor applications with ambipolar characteristics and non-volatile memory applications. Here, we synthesized an organic semiconductor, PDPPT-TT, and directly utilized it in both field-effect transistor and non-volatile memory applications. As-synthesized PDPPT-TT was simply spin-coated on a substrate for the device fabrications. The PDPPT-TT based field-effect transistor showed ambipolar electrical transfer characteristics. Furthermore, a gold nanoparticle-embedded dielectric layer was used as a charge trapping layer for the non-volatile memory device applications. The non-volatile memory device showed clear memory window formation as applied gate voltage increases, and electrical stability was evaluated by performing retention and cycling tests. In summary, we demonstrate that a donor–acceptor-type organic semiconductor molecule shows great potential for ambipolar field-effect transistors and non-volatile memory device applications as an important class of materials.

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