scholarly journals Modeling of on-off Current and Cutoff Frequency in Organic Thin Film Transistors

2020 ◽  
Vol 9 (3) ◽  
pp. 3028-3035
Keyword(s):  
Thin Film ◽  
Integrated Circuit ◽  
Thin Film Transistors ◽  
Low Cost ◽  
Cutoff Frequency ◽  
Channel Length ◽  
Organic Thin Film Transistors ◽  
Model Parameters ◽  
Organic Thin Film ◽  
Short Channel

Organic thin-film transistors (OTFTs) are providing incitement in various integrated circuit applications because of advantages like low cost and being flexible. In this paper we present an analytical modeling of on-off current and cutoff frequency in organic thin film transistors. The proposed model accurately describes both the parameters uniquely and is based on the standard equations of transistor. The model parameters are listed out and simulation of the final model is performed in MATLAB. Furthermore, it has been concluded that the high cutoff frequency of OTFTs can be achieved with short channel length and high gate voltage; further high on-off current ratio can be attained by lowering semiconducting layers’ thickness and increasing the mobility

Flexible, high mobility short-channel organic thin film transistors and logic circuits based on 4H-21DNTT

2021 ◽  
Author(s):  
Anubha Bilgaiyan ◽  
Seung-Il Cho ◽  
Miho Abiko ◽  
Kaori Watanabe ◽  
Makoto Mizukami
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
High Performance ◽  
Channel Length ◽  
Logic Circuits ◽  
Organic Thin Film Transistors ◽  
Limiting Factors ◽  
Organic Thin Film ◽  
Short Channel ◽  
Inverter Circuit

Abstract The low mobility and large contact resistance in organic thin-film transistors (OTFTs) are the two major limiting factors in the development of high-performance organic logic circuits. Here, solution-processed high-performance OTFTs and circuits are reported with a polymeric gate dielectric and 6,6 bis (trans-4-butylcyclohexyl)-dinaphtho[2,1-b:2,1-f ]thieno[3,2-b]thiophene (4H-21DNTT) for the organic semiconducting layer. By optimizing and controlling the fabrication conditions, a record high saturation mobility of 8.8 cm2V− 1s− 1 was demonstrated as well as large on/off ratios (> 106) for relatively short channel lengths of 15 µm and an average carrier mobility of 10.5 cm2V-1s-1 for long channel length OTFTs (> 50 µm). The pseudo-CMOS inverter circuit with a channel length of 15 µm exhibited sharp switching characteristics with a high signal gain of 31.5 at a supply voltage of 20 V. In addition to the inverter circuit, NAND logic circuits were further investigated, which also exhibited remarkable logic characteristics, with a high gain, an operating frequency of 5 kHz, and a short propagation delay of 22.1 µs. The uniform and reproducible performance of 4H-21DNTT OTFTs show potential for large-area, low-cost real-world applications on industry-compatible bottom-contact substrates.

Organic Thin-Film Transistors with Short Channel Length Fabricated by Reverse Offset Printing

2011 ◽  
Vol 14 (8) ◽  
pp. H333 ◽  
Author(s):  
Minseok Kim ◽  
In-Kyu You ◽  
Hyun Han ◽  
Soon-Won Jung ◽  
Tae-Youb Kim ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
Channel Length ◽  
Organic Thin Film Transistors ◽  
Organic Thin Film ◽  
Offset Printing ◽  
Short Channel

Low-cost lithographically patterned source/drain bottom contacts for high mobility p-type organic thin film transistors

2012 ◽  
Vol 1435 ◽  
Author(s):  
Robert Mueller ◽  
Steve Smout ◽  
Myriam Willegems ◽  
Jan Genoe ◽  
Paul Heremans
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
High Performance ◽  
Low Cost ◽  
High Mobility ◽  
Organic Thin Film Transistors ◽  
Organic Thin Film ◽  
Short Channel ◽  
Bottom Contact ◽  
Gold Metallization

ABSTRACTShort channel organic thin film transistors in bottom-gate, bottom contact configuration use typically gold metallization for the source and drain contacts because this metal can easily be cleaned from photoresist residuals by oxygen plasma or ultraviolet-ozone and allows also surface modification by self-assembled monolayers (e.g. thiols). Alternative low-cost bottom contact metallization for high performance short-channel organic thin film transistors are scarce because of the incompatibility of the bottom contact material with the cleaning step. In this work a new process flow, involving a temporary thin aluminum protection layer, is presented. Short channel (3.4 μm) pentacene transistors with lithographical defined and thiol modified silver source/drain bottom contacts (25 nm thick, on a 2 nm titanium adhesion layer) prepared according to this process achieved a saturation mobility of 0.316 cm2/(V.s), and this at a metal cost below 1% of the standard 30 nm thick gold metallization.

scholarly journals Flexible, high mobility short-channel organic thin film transistors and logic circuits based on 4H–21DNTT

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anubha Bilgaiyan ◽  
Seung-Il Cho ◽  
Miho Abiko ◽  
Kaori Watanabe ◽  
Makoto Mizukami
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
High Performance ◽  
Channel Length ◽  
Logic Circuits ◽  
Organic Thin Film Transistors ◽  
Limiting Factors ◽  
Organic Thin Film ◽  
Short Channel ◽  
Inverter Circuit

AbstractThe low mobility and large contact resistance in organic thin-film transistors (OTFTs) are the two major limiting factors in the development of high-performance organic logic circuits. Here, solution-processed high-performance OTFTs and circuits are reported with a polymeric gate dielectric and 6,6 bis (trans-4-butylcyclohexyl)-dinaphtho[2,1-b:2,1-f]thieno[3,2-b]thiophene (4H–21DNTT) for the organic semiconducting layer. By optimizing and controlling the fabrication conditions, a high saturation mobility of 8.8 cm2 V−1 s−1 was demonstrated as well as large on/off ratios (> 106) for relatively short channel lengths of 15 μm and an average carrier mobility of 10.5 cm2 V−1 s−1 for long channel length OTFTs (> 50 μm). The pseudo-CMOS inverter circuit with a channel length of 15 μm exhibited sharp switching characteristics with a high signal gain of 31.5 at a supply voltage of 20 V. In addition to the inverter circuit, NAND logic circuits were further investigated, which also exhibited remarkable logic characteristics, with a high gain, an operating frequency of 5 kHz, and a short propagation delay of 22.1 μs. The uniform and reproducible performance of 4H–21DNTT OTFTs show potential for large-area, low-cost real-world applications on industry-compatible bottom-contact substrates.

Impacts of Channel Length and Type of Active Layer on Electrical Properties of Organic Thin-Film Transistors: Theoretical and Experimental Investigations

2020 ◽  
Vol 15 (4) ◽  
pp. 532-551
Author(s):  
S. Wageh ◽  
W. Boukhili ◽  
Ali Veysel Tunç ◽  
N. Hamad ◽  
Ahmed Al-Ghamdi
Keyword(s):  
Thin Film ◽  
Molecular Weight ◽  
Electrical Properties ◽  
Organic Semiconductor ◽  
Thin Film Transistors ◽  
Channel Length ◽  
Organic Thin Film Transistors ◽  
Organic Thin Film ◽  
Short Channel ◽  
Octadecyl Trichlorosilane

The organic thin film transistors made of different polymers with various channel lengths were fabricated, characterized and modeled. Three types of polymers with different polydispersity (PDI) and molecular weight were applied as active layers. Optimizing OTFTs were achieved by two technological ways, namely the treatment of SiO2 by octadecyl trichlorosilane (OTS) (self-assembled monolayers (SAM)) in correlation with channel length variation. The effect of treatment of SiO2 by OTS (octadecyl trichlorosilane) on the output and transfer characteristics along with the electrical parameters were investigated. In addition, the effects of polydispersity (PDI) and molecular weight of organic semiconductor were accounted. The characteristics of transistors depended on the exposure to SiO2 by OTS, channel length, polydispersity (PDI) and molecular weight of polymers. The devices fabricated with treatment of SiO2 by OTS along with organic semiconductor, possessing high molecular weight has a channel length of 2.5 μm, which showed outstanding mobility of 10–2 cm2V –1s–1, current ratio Ion/Ioff = 2.5 × 106 and a low contact resistance of 4.8 × 10 5 Ω. An analytical model reproduced output electrical properties having characteristics of fabricated devices. The obtained results by the model were fairly agreed with those obtained experimentally for long and short channel devices.

Suppression of short channel effect in organic thin film transistors

2007 ◽  
Vol 91 (11) ◽  
pp. 113508 ◽  
Author(s):  
K. Tukagoshi ◽  
F. Fujimori ◽  
T. Minari ◽  
T. Miyadera ◽  
T. Hamano ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
Organic Thin Film Transistors ◽  
Organic Thin Film ◽  
Short Channel ◽  
Short Channel Effect ◽  
Channel Effect

scholarly journals Bias Stress in Organic Thin-Film Transistors Towards Low-Cost Flexible Gas Sensors

2021 ◽  
Vol 16 (2) ◽  
pp. 1-11
Author(s):  
José Enrique Eirez Izquierdo ◽  
José Diogo da Silva Oliveira ◽  
Vinicius Augusto Machado Nogueira ◽  
Dennis Cabrera García ◽  
Marco Roberto Cavallari ◽  
...  
Keyword(s):  
Thin Film ◽  
Flexible Electronics ◽  
Thin Film Transistors ◽  
Low Cost ◽  
Thin Film Deposition ◽  
Dielectric Surface ◽  
Organic Thin Film Transistors ◽  
Film Deposition ◽  
Organic Thin Film ◽  
Bias Stress

This work is focused on the bias stress (BS) effects in Organic Thin-Film Transistors (OTFTs) from poly(2,5-bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophene) (PBTTT-C14) on both highly-doped Si and glass substrates. While the former had a thermally-grown SiO2 dielectric, the latter demanded an alternative dielectric that should be capable to withstand bottom contact lithography, as well as semiconducting thin-film deposition. In addition, it should represent one more step towards flexible electronics. In order to do that, poly(4-vinylphenol) (PVP) was blended to poly(melamine-co-formaldehyde) methylated (PMF). OTFTs on glass with a cross-linked polymer dielectric had a charge carrier mobility (μ) of 4.0x10-4 cm2/Vs, threshold voltage (VT) of 18 V, current modulation (ION/OFF) higher than 1x102, and subthreshold slope (SS) of -7.7 V/dec. A negative BS shifted VT towards negative values and produced an increase in ION/OFF. A positive BS, on the other hand, produced the opposite effect only for OTFTs on Si. This is believed to be due to a higher trapping at the PVP:PMF interface with PBTTT-C14. Modeling the device current along time by a stretched exponential provided shorter time constants of ca. 105 s and higher exponents of 0.7–0.9 for devices on glass. Due to the presence of increased BS effects, the application of organic TFTs based on PVP:PMF as flexible sensors will require compensating circuits, lower voltages or less measurements in time. Alternatively, BS effects could be reduced by a dielectric surface treatment.

Sign in / Sign up

Export Citation Format

Share Document