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Sim HR, Lee S, Lee J, Hassan SZ, Nam GH, So C, Sim KM, Chung DS. Liquid-Film Rupture for Web-like Ag Nanowires toward High-Performance Organic Schottky Barrier Transistors. ACS NANO 2023. [PMID: 38039187 DOI: 10.1021/acsnano.3c10663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2023]
Abstract
Organic vertical transistors are promising device with benefits such as high operation speed, high saturation current density, and low-voltage operation owing to their short channel length. However, a short channel length leads to a high off-current, which is undesirable because it affects the on-off ratio and power consumption. This study presents a breakthrough in the development of high-performance organic Schottky barrier transistors (OSBTs) with a low off-current by utilizing a near-ideal source electrode with a web-like Ag nanowire (AgNW) morphology. This is achieved by employing a humidity- and surface-tension-mediated liquid-film rupture technique, which facilitates the formation of well-connected AgNW networks with large pores between them. Therefore, the gate electric field is effectively transmitted to the semiconductor layer. Also, the minimized surface area of the AgNWs causes complete suppression of the off-current and induces ideal saturation of the OSBT output characteristics. p- and n-type OSBTs exhibit off-currents in the picoampere range with on/off ratios exceeding 106 and 105, respectively. Furthermore, complementary inverters are prepared using an aryl azide cross-linker for patterning, with a gain of >16. This study represents a significant milestone in the development of high-performance organic vertical transistors and verifies their applicability in organic electronic circuitry.
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Affiliation(s)
- Hye Ryun Sim
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Sangjun Lee
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Juhyeok Lee
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Syed Zahid Hassan
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Geon-Hee Nam
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Chan So
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Kyu Min Sim
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Dae Sung Chung
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
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Hamadani BH. 2.11 - Accurate characterization of indoor photovoltaic performance. JPHYS MATERIALS 2023; 6:10.1088/2515-7639/acc550. [PMID: 37965623 PMCID: PMC10644663 DOI: 10.1088/2515-7639/acc550] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
Abstract
Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g. combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g. smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyses the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere.
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Höppner M, Kheradmand‐Boroujeni B, Vahland J, Sawatzki MF, Kneppe D, Ellinger F, Kleemann H. High-Frequency Operation of Vertical Organic Field-Effect Transistors. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2201660. [PMID: 35754312 PMCID: PMC9403633 DOI: 10.1002/advs.202201660] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 05/12/2022] [Indexed: 06/15/2023]
Abstract
The high-frequency and low-voltage operation of organic thin-film transistors (OTFTs) is a key requirement for the commercial success of flexible electronics. Significant progress has been achieved in this regard by several research groups highlighting the potential of OTFTs to operate at several tens or even above 100 MHz. However, technology maturity, including scalability, integrability, and device reliability, is another crucial point for the semiconductor industry to bring OTFT-based flexible electronics into mass production. These requirements are often not met by high-frequency OTFTs reported in the literature as unconventional processes, such as shadow-mask patterning or alignment with unrealistic tolerances for production, are used. Here, ultra-short channel vertical organic field-effect transistors (VOFETs) with a unity current gain cut-off frequency (fT ) up to 43.2 MHz (or 4.4 MHz V-1 ) operating below 10 V are shown. Using state-of-the-art manufacturing techniques such as photolithography with reliable fabrication procedures, the integration of such devices down to the size of only 12 × 6 µm2 is shown, which is important for the adaption of this technology in high-density circuits (e.g., display driving). The intrinsic channel transconductance is analyzed and demonstrates that the frequencies up to 430 MHz can be reached if the parasitic electrode overlap is minimized.
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Affiliation(s)
- Marco Höppner
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität Dresden01069DresdenGermany
| | - Bahman Kheradmand‐Boroujeni
- Chair of Circuit Design and Network Theory (CCN)Technische Universität DresdenHelmholtz Str. 1801069DresdenGermany
- Center for Advancing Electronics Dresden (cfaed)Technische Universität DresdenWürzburgerstr. 4601187DresdenGermany
| | - Jörn Vahland
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität Dresden01069DresdenGermany
| | - Michael Franz Sawatzki
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität Dresden01069DresdenGermany
| | - David Kneppe
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität Dresden01069DresdenGermany
| | - Frank Ellinger
- Chair of Circuit Design and Network Theory (CCN)Technische Universität DresdenHelmholtz Str. 1801069DresdenGermany
- Center for Advancing Electronics Dresden (cfaed)Technische Universität DresdenWürzburgerstr. 4601187DresdenGermany
| | - Hans Kleemann
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität Dresden01069DresdenGermany
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Wang SJ, Sawatzki M, Darbandy G, Talnack F, Vahland J, Malfois M, Kloes A, Mannsfeld S, Kleemann H, Leo K. Organic bipolar transistors. Nature 2022; 606:700-705. [PMID: 35732763 PMCID: PMC9217747 DOI: 10.1038/s41586-022-04837-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/05/2022] [Indexed: 11/09/2022]
Abstract
Devices made using thin-film semiconductors have attracted much interest recently owing to new application possibilities. Among materials systems suitable for thin-film electronics, organic semiconductors are of particular interest; their low cost, biocompatible carbon-based materials and deposition by simple techniques such as evaporation or printing enable organic semiconductor devices to be used for ubiquitous electronics, such as those used on or in the human body or on clothing and packages1–3. The potential of organic electronics can be leveraged only if the performance of organic transistors is improved markedly. Here we present organic bipolar transistors with outstanding device performance: a previously undescribed vertical architecture and highly crystalline organic rubrene thin films yield devices with high differential amplification (more than 100) and superior high-frequency performance over conventional devices. These bipolar transistors also give insight into the minority carrier diffusion length—a key parameter in organic semiconductors. Our results open the door to new device concepts of high-performance organic electronics with ever faster switching speeds. An organic bipolar junction transistor composed of highly crystalline rubrene thin films has a device architecture that could be used in organic electronics with greatly improved high-frequency performance
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Affiliation(s)
- Shu-Jen Wang
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, Dresden, Germany
| | - Michael Sawatzki
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, Dresden, Germany
| | - Ghader Darbandy
- NanoP, Technische Hochschule Mittelhessen, University of Applied Science, Gießen, Germany
| | - Felix Talnack
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, Dresden, Germany
| | - Jörn Vahland
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, Dresden, Germany
| | | | - Alexander Kloes
- NanoP, Technische Hochschule Mittelhessen, University of Applied Science, Gießen, Germany
| | - Stefan Mannsfeld
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, Dresden, Germany
| | - Hans Kleemann
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, Dresden, Germany
| | - Karl Leo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, Dresden, Germany. .,Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, Dresden, Germany.
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MXene based saturation organic vertical photoelectric transistors with low subthreshold swing. Nat Commun 2022; 13:2898. [PMID: 35610215 PMCID: PMC9130145 DOI: 10.1038/s41467-022-30527-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 05/02/2022] [Indexed: 12/21/2022] Open
Abstract
Vertical transistors have attracted enormous attention in the next-generation electronic devices due to their high working frequency, low operation voltage and large current density, while a major scientific and technological challenge for high performance vertical transistor is to find suitable source electrode. Herein, an MXene material, Ti3C2Tx, is introduced as source electrode of organic vertical transistors. The porous MXene films take the advantage of both partially shielding effect of graphene and the direct modulation of the Schottky barrier at the mesh electrode, which significantly enhances the ability of gate modulation and reduces the subthreshold swing to 73 mV/dec. More importantly, the saturation of output current which is essential for all transistor-based applications but remains a great challenge for vertical transistors, is easily achieved in our device due to the ultra-thin thickness and native oxidation of MXene, as verified by finite-element simulations. Finally, our device also possesses great potential for being used as wide-spectrum photodetector with fast response speed without complex material and structure design. This work demonstrates that MXene as source electrode offers plenty of opportunities for high performance vertical transistors and photoelectric devices. The modulation of Schottky barrier, which dominates the carrier injection in vertical organic field-effect transistors, strongly depends on the source electrode. Here, Chen et al. utilize MXene as a source electrode, achieving a subthreshold swing down to 73 mv/dec and a large gate control ability.
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Zschieschang U, Waizmann U, Weis J, Borchert JW, Klauk H. Nanoscale flexible organic thin-film transistors. SCIENCE ADVANCES 2022; 8:eabm9845. [PMID: 35363511 PMCID: PMC10938573 DOI: 10.1126/sciadv.abm9845] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 02/10/2022] [Indexed: 06/14/2023]
Abstract
Direct-write electron-beam lithography has been used to fabricate low-voltage p-channel and n-channel organic thin-film transistors with channel lengths as small as 200 nm and gate-to-contact overlaps as small as 100 nm on glass and on flexible transparent polymeric substrates. The p-channel transistors have on/off current ratios as large as 4 × 109 and subthreshold swings as small as 70 mV/decade, and the n-channel transistors have on/off ratios up to 108 and subthreshold swings as low as 80 mV/decade. These are the largest on/off current ratios reported to date for nanoscale organic transistors. Inverters based on two p-channel transistors with a channel length of 200 nm and gate-to-contact overlaps of 100 nm display characteristic switching-delay time constants between 80 and 40 ns at supply voltages between 1 and 2 V, corresponding to a supply voltage-normalized frequency of about 6 MHz/V. This is the highest voltage-normalized dynamic performance reported to date for organic transistors fabricated by maskless lithography.
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Affiliation(s)
- Ute Zschieschang
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
| | - Ulrike Waizmann
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
| | - Jürgen Weis
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
| | - James W. Borchert
- 1st Institute of Physics, Georg August University of Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany
| | - Hagen Klauk
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
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8
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Borchert JW, Weitz RT, Ludwigs S, Klauk H. A Critical Outlook for the Pursuit of Lower Contact Resistance in Organic Transistors. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2104075. [PMID: 34623710 DOI: 10.1002/adma.202104075] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 08/20/2021] [Indexed: 06/13/2023]
Abstract
To take full advantage of recent and anticipated improvements in the performance of organic semiconductors employed in organic transistors, the high contact resistance arising at the interfaces between the organic semiconductor and the source and drain contacts must be reduced significantly. To date, only a small portion of the accumulated research on organic thin-film transistors (TFTs) has reported channel-width-normalized contact resistances below 100 Ωcm, well above what is regularly demonstrated in transistors based on inorganic semiconductors. A closer look at these cases and the relevant literature strongly suggests that the most significant factor leading to the lowest contact resistances in organic TFTs so far has been the control of the thin-film morphology of the organic semiconductor. By contrast, approaches aimed at increasing the charge-carrier density and/or reducing the intrinsic Schottky barrier height have so far played a relatively minor role in achieving the lowest contact resistances. Herein, the possible explanations for these observations are explored, including the prevalence of Fermi-level pinning and the difficulties in forming optimized interfaces with organic semiconductors. An overview of the research on these topics is provided, and potential device-engineering solutions are discussed based on recent advancements in the theoretical and experimental work on both organic and inorganic semiconductors.
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Affiliation(s)
- James W Borchert
- 1st Institute of Physics, Georg August University of Göttingen, Friedrich-Hund-Platz 1, 37077, Göttingen, Germany
| | - R Thomas Weitz
- 1st Institute of Physics, Georg August University of Göttingen, Friedrich-Hund-Platz 1, 37077, Göttingen, Germany
| | - Sabine Ludwigs
- IPOC - Functional Polymers, Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Hagen Klauk
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569, Stuttgart, Germany
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9
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Wu Z, Liu Y, Guo E, Darbandy G, Wang SJ, Hübner R, Kloes A, Kleemann H, Leo K. Efficient and low-voltage vertical organic permeable base light-emitting transistors. NATURE MATERIALS 2021; 20:1007-1014. [PMID: 33649562 DOI: 10.1038/s41563-021-00937-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 01/18/2021] [Indexed: 06/12/2023]
Abstract
Organic light-emitting transistors, three-terminal devices combining a thin-film transistor with a light-emitting diode, have generated increasing interest in organic electronics. However, increasing their efficiency while keeping the operating voltage low still remains a key challenge. Here, we demonstrate organic permeable base light-emitting transistors; these three-terminal vertical optoelectronic devices operate at driving voltages below 5.0 V; emit in the red, green and blue ranges; and reach, respectively, peak external quantum efficiencies of 19.6%, 24.6% and 11.8%, current efficiencies of 20.6 cd A-1, 90.1 cd A-1 and 27.1 cd A-1 and maximum luminance values of 9,833 cd m-2, 12,513 cd m-2 and 4,753 cd m-2. Our simulations demonstrate that the nano-pore permeable base electrode located at the centre of the device, which forms a distinctive optical microcavity and regulates charge carrier injection and transport, is the key to the good performance obtained. Our work paves the way towards efficient and low-voltage organic light-emitting transistors, useful for power-efficient active matrix displays and solid-state lighting.
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Affiliation(s)
- Zhongbin Wu
- Frontiers Science Center for Flexible Electronics, Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, Xi'an, China.
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany.
| | - Yuan Liu
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
| | - Erjuan Guo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Ghader Darbandy
- NanoP, TH Mittelhessen, University of Applied Sciences, Giessen, Germany
| | - Shu-Jen Wang
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - René Hübner
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Alexander Kloes
- NanoP, TH Mittelhessen, University of Applied Sciences, Giessen, Germany
| | - Hans Kleemann
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Karl Leo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
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Sawatzki MF, Kleemann H, Boroujeni BK, Wang S, Vahland J, Ellinger F, Leo K. Doped Highly Crystalline Organic Films: Toward High-Performance Organic Electronics. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2003519. [PMID: 33747740 PMCID: PMC7967074 DOI: 10.1002/advs.202003519] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/27/2020] [Indexed: 06/12/2023]
Abstract
Today's organic electronic devices, such as the highly successful OLED displays, are based on disordered films, with carrier mobilities orders of magnitude below those of inorganic semiconductors like silicon or GaAs. For organic devices such as diodes and transistors, higher charge carrier mobilities are paramount to achieve high performance. Organic single crystals have been shown to offer these required high mobilities. However, manufacturing and processing of these crystals are complex, rendering their use outside of laboratory-scale applications negligible. Furthermore, doping cannot be easily integrated into these systems, which is particularly problematic for devices mandating high mobility materials. Here, it is demonstrated for the model system rubrene that highly ordered, doped thin films can be prepared, allowing high-performance organic devices on almost any substrate. Specifically, triclinic rubrene crystals are created by abrupt heating of amorphous layers and can be electrically doped during the epitaxial growth process to achieve hole or electron conduction. Analysis of the space charge limited current in these films reveals record vertical mobilities of 10.3(49) cm2 V-1 s-1. To demonstrate the performance of this materials system, monolithic pin-diodes aimed for rectification are built. The f 3 d b of these diodes is over 1 GHz and thus higher than any other organic semiconductor-based device shown so far. It is believed that this work will pave the way for future high-performance organic devices based on highly crystalline thin films.
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Affiliation(s)
- Michael F. Sawatzki
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität DresdenNoethnitzer Str. 61Dresden01187Germany
| | - Hans Kleemann
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität DresdenNoethnitzer Str. 61Dresden01187Germany
| | - Bahman K. Boroujeni
- Chair of Circuit Design and Network Theory (CCN)Technische Universität DresdenHelmholtz Str. 18Dresden01069Germany
- Center for Advancing Electronics Dresden (cfaed)Technische Universität DresdenHelmholtz Str. 18Dresden01069Germany
| | - Shu‐Jen Wang
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität DresdenNoethnitzer Str. 61Dresden01187Germany
| | - Joern Vahland
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität DresdenNoethnitzer Str. 61Dresden01187Germany
| | - Frank Ellinger
- Chair of Circuit Design and Network Theory (CCN)Technische Universität DresdenHelmholtz Str. 18Dresden01069Germany
- Center for Advancing Electronics Dresden (cfaed)Technische Universität DresdenHelmholtz Str. 18Dresden01069Germany
| | - Karl Leo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP)Technische Universität DresdenNoethnitzer Str. 61Dresden01187Germany
- Center for Advancing Electronics Dresden (cfaed)Technische Universität DresdenHelmholtz Str. 18Dresden01069Germany
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11
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Perinot A, Giorgio M, Mattoli V, Natali D, Caironi M. Organic Electronics Picks Up the Pace: Mask-Less, Solution Processed Organic Transistors Operating at 160 MHz. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2001098. [PMID: 33643784 PMCID: PMC7887599 DOI: 10.1002/advs.202001098] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 09/15/2020] [Indexed: 06/12/2023]
Abstract
Organic printed electronics has proven its potential as an essential enabler for applications related to healthcare, entertainment, energy, and distributed intelligent objects. The possibility of exploiting solution-based and direct-writing production schemes further boosts the benefits offered by such technology, facilitating the implementation of cheap, conformable, bio-compatible electronic applications. The result shown in this work challenges the widespread assumption that such class of electronic devices is relegated to low-frequency operation, owing to the limited charge mobility of the materials and to the low spatial resolution achievable with conventional printing techniques. Here, it is shown that solution-processed and direct-written organic field-effect transistors can be carefully designed and fabricated so to achieve a maximum transition frequency of 160 MHz, unlocking an operational range that was not available before for organics. Such range was believed to be only accessible with more performing classes of semiconductor materials and/or more expensive fabrication schemes. The present achievement opens a route for cost- and energy-efficient manufacturability of flexible and conformable electronics with wireless-communication capabilities.
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Affiliation(s)
- Andrea Perinot
- Center for Nano Science and Technology@PoliMiIstituto Italiano di TecnologiaMilan20133Italy
| | - Michele Giorgio
- Center for Nano Science and Technology@PoliMiIstituto Italiano di TecnologiaMilan20133Italy
| | - Virgilio Mattoli
- Center for Micro‐BioRoboticsIstituto Italiano di TecnologiaPontedera56025Italy
| | - Dario Natali
- Center for Nano Science and Technology@PoliMiIstituto Italiano di TecnologiaMilan20133Italy
- Department of ElectronicsInformation and BioengineeringPolitecnico di MilanoMilan20133Italy
| | - Mario Caironi
- Center for Nano Science and Technology@PoliMiIstituto Italiano di TecnologiaMilan20133Italy
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Guo E, Wu Z, Darbandy G, Xing S, Wang SJ, Tahn A, Göbel M, Kloes A, Leo K, Kleemann H. Vertical organic permeable dual-base transistors for logic circuits. Nat Commun 2020; 11:4725. [PMID: 32948770 PMCID: PMC7501854 DOI: 10.1038/s41467-020-18576-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 08/21/2020] [Indexed: 11/30/2022] Open
Abstract
The main advantage of organic transistors with dual gates/bases is that the threshold voltages can be set as a function of the applied second gate/base bias, which is crucial for the application in logic gates and integrated circuits. However, incorporating a dual gate/base structure into an ultra-short channel vertical architecture represents a substantial challenge. Here, we realize a device concept of vertical organic permeable dual-base transistors, where the dual base electrodes can be used to tune the threshold voltages and change the on-currents. The detailed operation mechanisms are investigated by calibrated TCAD simulations. Finally, power-efficient logic circuits, e.g. inverter, NAND/AND computation functions are demonstrated with one single device operating at supply voltages of <2.0 V. We believe that this work offers a compact and technologically simple hardware platform with excellent application potential for vertical-channel organic transistors in complex logic circuits. The development of vertical organic transistors with controllable threshold voltage is highly desirable for integrated circuit-based displays and sensors. Here, the authors report vertical organic permeable dual-based transistors with independently tunable on-currents and threshold voltages.
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Affiliation(s)
- Erjuan Guo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
| | - Zhongbin Wu
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany. .,Frontiers Science Center for Flexible Electronics, Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, 710072, Xi'an, China.
| | - Ghader Darbandy
- NanoP, TH Mittelhessen, University of Applied Sciences, 35390, Giessen, Germany
| | - Shen Xing
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
| | - Shu-Jen Wang
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
| | - Alexander Tahn
- Dresden Center for Nanoanalysis (DCN), Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
| | - Michael Göbel
- Leibniz-Institut für Polymerforschung Dresden e.V. (IPF), 01069, Dresden, Germany
| | - Alexander Kloes
- NanoP, TH Mittelhessen, University of Applied Sciences, 35390, Giessen, Germany
| | - Karl Leo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany.
| | - Hans Kleemann
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
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Borchert JW, Zschieschang U, Letzkus F, Giorgio M, Weitz RT, Caironi M, Burghartz JN, Ludwigs S, Klauk H. Flexible low-voltage high-frequency organic thin-film transistors. SCIENCE ADVANCES 2020; 6:eaaz5156. [PMID: 32671209 PMCID: PMC7314562 DOI: 10.1126/sciadv.aaz5156] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 03/10/2020] [Indexed: 05/20/2023]
Abstract
The primary driver for the development of organic thin-film transistors (TFTs) over the past few decades has been the prospect of electronics applications on unconventional substrates requiring low-temperature processing. A key requirement for many such applications is high-frequency switching or amplification at the low operating voltages provided by lithium-ion batteries (~3 V). To date, however, most organic-TFT technologies show limited dynamic performance unless high operating voltages are applied to mitigate high contact resistances and large parasitic capacitances. Here, we present flexible low-voltage organic TFTs with record static and dynamic performance, including contact resistance as small as 10 Ω·cm, on/off current ratios as large as 1010, subthreshold swing as small as 59 mV/decade, signal delays below 80 ns in inverters and ring oscillators, and transit frequencies as high as 21 MHz, all while using an inverted coplanar TFT structure that can be readily adapted to industry-standard lithographic techniques.
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Affiliation(s)
- James W. Borchert
- Max Planck Institute for Solid State Research, Stuttgart, Germany
- Institute of Polymer Chemistry, Universität Stuttgart, Stuttgart, Germany
| | - Ute Zschieschang
- Max Planck Institute for Solid State Research, Stuttgart, Germany
| | - Florian Letzkus
- Institut für Mikroelektronik Stuttgart (IMS CHIPS), Stuttgart, Germany
| | - Michele Giorgio
- Center for Nano Science and Technology@PoliMi Milano, Istituto Italiano di Tecnologia, Milan, Italy
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan, Italy
| | - R. Thomas Weitz
- Physics of Nanosystems, Department of Physics, Ludwig-Maximilians-Universität München, Germany
- Center for Nanoscience (CeNS), Munich, Germany
- Munich Center for Quantum Science and Technology (MCQST), Munich, Germany
| | - Mario Caironi
- Center for Nano Science and Technology@PoliMi Milano, Istituto Italiano di Tecnologia, Milan, Italy
| | | | - Sabine Ludwigs
- Institute of Polymer Chemistry, Universität Stuttgart, Stuttgart, Germany
| | - Hagen Klauk
- Max Planck Institute for Solid State Research, Stuttgart, Germany
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14
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Irimia-Vladu M, Kanbur Y, Camaioni F, Coppola ME, Yumusak C, Irimia CV, Vlad A, Operamolla A, Farinola GM, Suranna GP, González-Benitez N, Molina MC, Bautista LF, Langhals H, Stadlober B, Głowacki ED, Sariciftci NS. Stability of Selected Hydrogen Bonded Semiconductors in Organic Electronic Devices. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2019; 31:6315-6346. [PMID: 32565617 PMCID: PMC7297463 DOI: 10.1021/acs.chemmater.9b01405] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 07/11/2019] [Indexed: 05/02/2023]
Abstract
The electronics era is flourishing and morphing itself into Internet of Everything, IoE. At the same time, questions arise on the issue of electronic materials employed: especially their natural availability and low-cost fabrication, their functional stability in devices, and finally their desired biodegradation at the end of their life cycle. Hydrogen bonded pigments and natural dyes like indigo, anthraquinone and acridone are not only biodegradable and of bio-origin but also have functionality robustness and offer versatility in designing electronics and sensors components. With this Perspective, we intend to coalesce all the scattered reports on the above-mentioned classes of hydrogen bonded semiconductors, spanning across several disciplines and many active research groups. The article will comprise both published and unpublished results, on stability during aging, upon electrical, chemical and thermal stress, and will finish with an outlook section related to biological degradation and biological stability of selected hydrogen bonded molecules employed as semiconductors in organic electronic devices. We demonstrate that when the purity, the long-range order and the strength of chemical bonds, are considered, then the Hydrogen bonded organic semiconductors are the privileged class of materials having the potential to compete with inorganic semiconductors. As an experimental historical study of stability, we fabricated and characterized organic transistors from a material batch synthesized in 1932 and compared the results to a fresh material batch.
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Affiliation(s)
- Mihai Irimia-Vladu
- Joanneum
Research Forschungsgesellschaft mbH, Franz-Pichler Str. Nr. 30, 8160 Weiz, Austria
- Linz
Institute for Organic Solar Cells (LIOS), Physical Chemistry, Johannes Kepler University Linz, Altenberger Str. Nr. 69, 4040 Linz, Austria
- Mihai
Irimia-Vladu. E-mail:
| | - Yasin Kanbur
- Linz
Institute for Organic Solar Cells (LIOS), Physical Chemistry, Johannes Kepler University Linz, Altenberger Str. Nr. 69, 4040 Linz, Austria
- Department
of Metallurgical and Materials Engineering, Karabuk University, BaliklarkayasiMevkii, 78050 Karabük, Turkey
| | - Fausta Camaioni
- Joanneum
Research Forschungsgesellschaft mbH, Franz-Pichler Str. Nr. 30, 8160 Weiz, Austria
- School
of Industrial and Information Engineering, Politecnico di Milano, Via Raffaele Lambruschini, 15, 20156 Milano, Milan, Italy
| | - Maria Elisabetta Coppola
- Joanneum
Research Forschungsgesellschaft mbH, Franz-Pichler Str. Nr. 30, 8160 Weiz, Austria
- School
of Industrial and Information Engineering, Politecnico di Milano, Via Raffaele Lambruschini, 15, 20156 Milano, Milan, Italy
| | - Cigdem Yumusak
- Linz
Institute for Organic Solar Cells (LIOS), Physical Chemistry, Johannes Kepler University Linz, Altenberger Str. Nr. 69, 4040 Linz, Austria
| | - Cristian Vlad Irimia
- Joanneum
Research Forschungsgesellschaft mbH, Franz-Pichler Str. Nr. 30, 8160 Weiz, Austria
- Bundesrealgymnasium
Seebacher, Seebachergasse 11, 8010 Graz, Austria
| | - Angela Vlad
- National
Institute for Laser, Plasma and Radiation Physics (INFLPR), Atomistilor Street, No. 409, Magurele, Bucharest, 077125 Ilfov, Romania
| | - Alessandra Operamolla
- Dipartimento
di Chimica, Università degli Studi
di Bari Aldo Moro, Via E. Orabona 4, I-70126 Bari, Italy
| | - Gianluca M. Farinola
- Dipartimento
di Chimica, Università degli Studi
di Bari Aldo Moro, Via E. Orabona 4, I-70126 Bari, Italy
| | - Gian Paolo Suranna
- Department
of Civil, Environmental and Chemical Engineering (DICATECh), Politecnico di Bari, Via Orabona 4, 70125 Bari, Italy
| | - Natalia González-Benitez
- Department
of Biology and Geology, Physics and Inorganic Chemistry, Rey Juan Carlos University, Calle Tulipán s/n, 28933 Móstoles (Madrid), Spain
| | - Maria Carmen Molina
- Department
of Biology and Geology, Physics and Inorganic Chemistry, Rey Juan Carlos University, Calle Tulipán s/n, 28933 Móstoles (Madrid), Spain
| | - Luis Fernando Bautista
- Department
of Chemical and Environmental Technology, Rey Juan Carlos University, Calle Tulipán s/n, 28933 Móstoles (Madrid), Spain
| | - Heinz Langhals
- Linz
Institute for Organic Solar Cells (LIOS), Physical Chemistry, Johannes Kepler University Linz, Altenberger Str. Nr. 69, 4040 Linz, Austria
- Department
Department of Chemistry, Ludwig-Maximilians
University München, Butenandtstr. 13, D-81377 München, Germany
| | - Barbara Stadlober
- Joanneum
Research Forschungsgesellschaft mbH, Franz-Pichler Str. Nr. 30, 8160 Weiz, Austria
| | - Eric Daniel Głowacki
- Linz
Institute for Organic Solar Cells (LIOS), Physical Chemistry, Johannes Kepler University Linz, Altenberger Str. Nr. 69, 4040 Linz, Austria
- Linköping
University, Department of Science
and Technology, Laboratory of Organic Electronics, Bredgatan 33, Norrköping 60221, Sweden
| | - Niyazi Serdar Sariciftci
- Linz
Institute for Organic Solar Cells (LIOS), Physical Chemistry, Johannes Kepler University Linz, Altenberger Str. Nr. 69, 4040 Linz, Austria
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15
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Fan X, Kneppe D, Sayevich V, Kleemann H, Tahn A, Leo K, Lesnyak V, Eychmüller A. High-Performance Ultra-Short Channel Field-Effect Transistor Using Solution-Processable Colloidal Nanocrystals. J Phys Chem Lett 2019; 10:4025-4031. [PMID: 31259561 DOI: 10.1021/acs.jpclett.9b01649] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We demonstrate high-mobility solution-processed inorganic field-effect transistors (FETs) with ultra-short channel (USC) length using semiconductor CdSe nanocrystals (NCs). Capping of the NCs with hybrid inorganic-organic CdCl3--butylamine ligands enables coarsening of the NCs during annealing at a moderate temperature, resulting in the devices having good transport characteristics with electron mobilities in the saturation regime reaching 8 cm2 V-1 s-1. Solution-based processing of the NCs and fabrication of thin films involve neither harsh conditions nor the use of hydrazine. Employing photolithographic methods, we fabricated FETs with a vertical overlap of source and drain electrodes to achieve a submicrometer channel length. To the best of our knowledge, this is the first report on an USC FET based on colloidal semiconductor NCs. Because of a short channel length, the FETs show a normalized transconductance of 4.2 m V-1 s-1 with a high on/off ratio of 105.
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Affiliation(s)
- Xuelin Fan
- Physical Chemistry , TU Dresden , Bergstrasse 66b , 01062 Dresden , Germany
| | - David Kneppe
- Dresden Integrated Center for Applied Photophysics and Photonic Materials , TU Dresden , Nöthnitzer Strasse 61 , 01187 Dresden , Germany
| | - Vladimir Sayevich
- Physical Chemistry , TU Dresden , Bergstrasse 66b , 01062 Dresden , Germany
| | - Hans Kleemann
- Dresden Integrated Center for Applied Photophysics and Photonic Materials , TU Dresden , Nöthnitzer Strasse 61 , 01187 Dresden , Germany
| | - Alexander Tahn
- Dresden Center for Nanoanalysis , TU Dresden , Helmholtzstrasse 18 , 01069 Dresden , Germany
| | - Karl Leo
- Dresden Integrated Center for Applied Photophysics and Photonic Materials , TU Dresden , Nöthnitzer Strasse 61 , 01187 Dresden , Germany
| | - Vladimir Lesnyak
- Physical Chemistry , TU Dresden , Bergstrasse 66b , 01062 Dresden , Germany
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16
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Dollinger F, Lim KG, Li Y, Guo E, Formánek P, Hübner R, Fischer A, Kleemann H, Leo K. Vertical Organic Thin-Film Transistors with an Anodized Permeable Base for Very Low Leakage Current. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1900917. [PMID: 30920705 DOI: 10.1002/adma.201900917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/09/2019] [Indexed: 06/09/2023]
Abstract
The organic permeable base transistor (OPBT) is currently the fastest organic transistor with a transition frequency of 40 MHz. It relies on a thin aluminum base electrode to control the transistor current. This electrode is surrounded by a native oxide layer for passivation, currently created by oxidation in air. However, this process is not reliable and leads to large performance variations between samples, slow production, and relatively high leakage currents. Here, for the first time it is demonstrated that electrochemical anodization can be conveniently employed for the fabrication of high-performance OPBTs with vastly reduced leakage currents and more controlled process parameters. Very large transmission factors of 99.9996% are achieved, while excellent on/off ratios of 5 × 105 and high on-currents greater than 300 mA cm-2 show that the C60 semiconductor layer can withstand the electrochemical anodization. These results make anodization an intriguing option for innovative organic transistor design.
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Affiliation(s)
- Felix Dollinger
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
| | - Kyung-Geun Lim
- Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea
| | - Yang Li
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
| | - Erjuan Guo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
| | - Peter Formánek
- Leibniz-Institut für Polymerforschung Dresden e. V. (IPF), 01069, Dresden, Germany
| | - René Hübner
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Axel Fischer
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
| | - Hans Kleemann
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
| | - Karl Leo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, 01062, Dresden, Germany
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17
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Perinot A, Caironi M. Accessing MHz Operation at 2 V with Field-Effect Transistors Based on Printed Polymers on Plastic. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1801566. [PMID: 30828529 PMCID: PMC6382309 DOI: 10.1002/advs.201801566] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 10/23/2018] [Indexed: 05/24/2023]
Abstract
Organic printed electronics are suitable for the development of wearable, lightweight, distributed applications in combination with cost-effective production processes. Nonetheless, some necessary features for several envisioned disruptive mass-produced products are still lacking: among these radio-frequency (RF) communication capability, which requires high operational speed combined with low supply voltage in electronic devices processed on cheap plastic foils. Here, it is demonstrated that high-frequency, low-voltage, polymer field-effect transistors can be fabricated on plastic with the sole use of a combination of scalable printing and digital laser-based techniques. These devices reach an operational frequency in excess of 1 MHz at the challengingly low bias voltage of 2 V, and exceed 14 MHz operation at 7 V. In addition, when integrated into a rectifying circuit, they can provide a DC voltage at an input frequency of 13.56 MHz, opening the way for the implementation of RF devices and tags with cost-effective production processes.
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Affiliation(s)
- Andrea Perinot
- Center for Nano Science and Technology@PoliMiIstituto Italiano di Tecnologiavia Giovanni Pascoli 70/320133MilanItaly
| | - Mario Caironi
- Center for Nano Science and Technology@PoliMiIstituto Italiano di Tecnologiavia Giovanni Pascoli 70/320133MilanItaly
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18
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Stadlober B, Zirkl M, Irimia-Vladu M. Route towards sustainable smart sensors: ferroelectric polyvinylidene fluoride-based materials and their integration in flexible electronics. Chem Soc Rev 2019; 48:1787-1825. [DOI: 10.1039/c8cs00928g] [Citation(s) in RCA: 153] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Printed ferroelectric devices are ideal candidates for self-powered and multifunctional sensor skins, contributing to a sustainable smart future.
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Affiliation(s)
| | - Martin Zirkl
- Joanneum Research Forschungsgesellschaft mbH
- 8160 Weiz
- Austria
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19
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Klinger MP, Fischer A, Kleemann H, Leo K. Non-Linear Self-Heating in Organic Transistors Reaching High Power Densities. Sci Rep 2018; 8:9806. [PMID: 29955076 PMCID: PMC6023904 DOI: 10.1038/s41598-018-27689-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/06/2018] [Indexed: 11/23/2022] Open
Abstract
The improvement of the performance of organic thin-film transistors is driven by novel materials and improved device engineering. Key developments are a continuous increase of the charge carrier mobility, a scale-down of transistor dimensions, and the reduction of contact resistance. Furthermore, new transistor designs such as vertical devices are introduced to benefit from drastically reduced channel length while keeping the effort for structuring moderate. Here, we show that a strong electrothermal feedback occurs in organic transistors, ultimately leading to output characteristics with regions of S-shaped negative differential resistance. For that purpose, we use an organic permeable-base transistor (OPBT) with outstanding current densities, where a strong and reproducible, non-linear electrothermal feedback is revealed. We derive an analytical description of the temperature dependent current-voltage behavior and offer a rapid investigation method for material systems, where a temperature-activated conductivity can be observed.
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Affiliation(s)
- Markus P Klinger
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, Germany.
| | - Axel Fischer
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, Germany
| | - Hans Kleemann
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, Germany
- Center for Advancing Electronics Dresden (cfead), Technische Universität Dresden, Würzburger Str. 43, 01187, Dresden, Germany
| | - Karl Leo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, Germany
- Center for Advancing Electronics Dresden (cfead), Technische Universität Dresden, Würzburger Str. 43, 01187, Dresden, Germany
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