Performance Improvement in single-gate organic transistors with contacts at top and bottom: Additional p + region insertion near source and drain

2021 ◽  
pp. 1-19
Author(s):  
Sakshi Gupta ◽  
Poornima Mittal ◽  
Pradeep Juneja
Keyword(s):  
Drain Current ◽  
Channel Length ◽  
Considerable Change ◽  
Organic Transistors ◽  
Organic Thin Film ◽  
High Concentration ◽  
Bottom Contact ◽  
Contact Devices ◽  
Bottom Gate

This research explores performance attributes of bottom gate top contact (BGTC) and bottom gate bottom contact (BGBC) organic thin film transistors (OTFT). To upgrade the performance characteristics, a region of 5nm with high concentration of carrier is tallied neighboring contacts. The drain current for BGTC is –18.6μ A as compared to –5.1μ A of BGBC transistor. Also, it is established that the innate attributes of BGTC are better than those of their counterparts, which is typically considered because of the inadequate contact attributes and mediocre semiconductor quality of BGBC OTFT. The analysis showed that upon varying the length of the channel ranging from 5μm to 40μm, there was a significant change in the drain current of BGTC and BGBC devices. For the same values of V GS and V DS (0V to –5V) where drain current in BGTC structure varied from –129.86μ A to –13.69μ A, whereas for their counterparts it ranged from –37.10μ A to –3.76μ A for channel length equal to 5μ m and 40μ m respectively. Also, with the varying doping strength ranging from 1012 cm–3 to 1016 cm–3 for BGBC device, drain current varied from –2.15μ A to –18.52μ A for BGTC whereas for BGBC it varied from –0.19μ A to –7.09μ A keeping V GS and V DS –5 V, yielding that upon varying the doping strength, where for BGTC I D changed by a factor of 8.6, the BGBC device showed a considerable change by a factor of 37.3. Likewise, mobility, threshold voltage, sub-threshold swing and transconductance also showing better performance with the P + insertion. These variations in the innate attributes are primarily due to the deficiency of carriers at the interface of source and channel, leading to a greater drop in the potential, which is more prominent for the bottom gate bottom contact devices.

scholarly journals An Analysis of Aluminium Oxide and Silicon Dioxide as a Dielectric on Nano Structured Bottom Gate Bottom Contact Organic Thin Film Transistor Based Sensor

2020 ◽  
pp. 31-35
Author(s):  
Rajpoot Subhadra
Keyword(s):  
Thin Film ◽  
Silicon Dioxide ◽  
Gas Sensor ◽  
Dielectric Material ◽  
Thin Film Transistor ◽  
Drain Current ◽  
Organic Thin Film ◽  
Organic Thin Film Transistor ◽  
Bottom Contact ◽  
Bottom Gate

A Nano-structuredflexible bottom gate bottom contact (BGBC) organic thin film transistor based pentacenesensor was utilisedto compare between the two frequently used dielectric material i.ealuminiumoxide (Al2O3) and silicon dioxide (SiO2). The organic sensor served as an excellent gas sensor which was visualised through the simulation result in the form of variation between itsmax. and min. drain current and Ion /Ioffratio. The Ion / Ioffratio in the case ofaluminiumoxidewas found to be greater as compared to silicon dioxide whereas the minimum drain current was greater in the case of silicon dioxide and vice versa for the maximum drain current. On comparing the sensitivity of the device, which is the ratio of difference between min. drain current in the presence of any toxic gas and min. drain current in the absence of air to the min. drain current in the absence of air with respect tothe twodifferent electrodes wasfound to be 0.0314 for aluminiumoxide and 0.02964 for silicon dioxide. Hence, aluminiumoxide taking upper hand in sensitivity

Modelling and Simulation Approach for Organic Thin-Film Transistors Using MATLAB Simulation

2015 ◽  
Vol 1107 ◽  
pp. 514-519
Author(s):  
Umar Faruk Shuib ◽  
Khairul Anuar Mohamad ◽  
Afishah Alias ◽  
Tamer A. Tabet ◽  
Bablu K. Gosh ◽  
...  
Keyword(s):  
Thin Film ◽  
Low Cost ◽  
Thin Film Transistor ◽  
Drain Current ◽  
Mobility Model ◽  
Channel Length ◽  
Analytical Models ◽  
Organic Thin Film ◽  
Organic Thin Film Transistor ◽  
Organic Transistor

As organic transistors are preparing to make improvements towards flexible and low cost electronics applications, the analytical models and simulation methods were demanded to predict the optimized performance and circuit design. In this paper, we investigated the analytical model of an organic transistor device and simulate the output and transfer characteristics of the device using MATLAB tools for different channel length (L) of the organic transistor. In the simulation, the Pool-Frenkel mobility model was used to represent the conductive channel of organic transistor. The different channel length has been simulated with the value of 50 μm, 10 μm and 5 μm. This research paper analyses the performance of organic thin film transistor (TFT) for top contact bottom gate device. From the simulation, drain current of organic transistor was increased as the channel length decreased. Other extraction value such sub-threshold and current on/off ratio is 0.41 V and 21.1 respectively. Thus, the simulation provides significant extraction of information about the behaviour of the organic thin film transistor.

Effects of Device Architecture on the Performance of Organic Thin Film Transistors

2008 ◽  
Vol 1138 ◽  
Author(s):  
Xiaojing Zhou ◽  
Karyn E. Mutkins ◽  
Daniel Elkington ◽  
Kathleen Sirois ◽  
Warwick Belcher ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Film Transistor ◽  
Drain Current ◽  
Channel Length ◽  
Device Performance ◽  
Organic Thin Film ◽  
Organic Thin Film Transistor ◽  
Device Architecture ◽  
Electrochemical Transistor ◽  
The Impact

AbstractThe impact of device dimension and architecture on the device performance of an all–solution fabrication organic thin film transistor (OTFT) has been investigated. The saturation drain current is inversely proportional to the channel length, indicating that a characteristic of field–effect like transistor has been obtained. In contrast, the drain current is independent of the thickness of polyvinylphenol (PVP) dielectric layer and a large leakage current is observed at the gate electrode indicating that the device also shows electrochemical transistor characteristics. Although separate conductance measurements of a single poly(3–hexylthiophene) (P3HT) layer and a P3HT/PVP layer reveal that the conductance is proportional to the thickness of the layer, the maximum achieved drain current in the fabricated OTFT is inversely proportional to the P3HT thickness. Using this data, an interface of P3HT/PVP or a maximum P3HT thickness for a working transistor of approximately 160 ± 16 nm can be extracted. The mechanism of operation of these devices is discussed.

Current Enhancement with Contact-Area-Limited Doping for Bottom-Gate, Bottom-Contact Organic Thin-Film Transistors

2013 ◽  
Vol 52 (2R) ◽  
pp. 021602 ◽  
Author(s):  
Kei Noda ◽  
Yusuke Wakatsuki ◽  
Yuji Yamagishi ◽  
Yasuo Wada ◽  
Toru Toyabe ◽  
...  
Keyword(s):  
Thin Film ◽  
Contact Area ◽  
Thin Film Transistors ◽  
Organic Thin Film Transistors ◽  
Organic Thin Film ◽  
Bottom Contact ◽  
Bottom Gate

Improvement of Short Channel Mobility and Operational Stability of Pentacene Bottom-Contact Transistors with a Sulfuric Acid and Hydrogen Peroxide Mixture (SPM) Treatment of Au Electrodes

2006 ◽  
Vol 965 ◽  
Author(s):  
Haruo Kawakami ◽  
Takahiko Maeda ◽  
Hisato Kato
Keyword(s):  
Hydrogen Peroxide ◽  
Sulfuric Acid ◽  
Contact Resistance ◽  
Gate Voltage ◽  
Field Effect ◽  
Field Effect Transistors ◽  
Drain Current ◽  
Channel Length ◽  
Short Channel ◽  
Bottom Contact

ABSTRACTWe report a reduction in the contact resistance between pentacene and Au source/drain electrodes of organic field effect transistors (OFETs) with bottom-contact structure. By immersing the Au electrodes in a sulfuric acid and hydrogen peroxide mixture (SPM), the injection barrier between the Au electrodes and pentacene was lowered by approximately 0.2 eV and the contact resistance significantly decreased. The fabricated bottom-contact OFETs revealed a field-effect mobility of more than 0.66 cm2/Vs at a channel length ranging from 3 to 30 μm, which is comparable to that of top-contact OFETs with a 50 μm channel length. The transfer characteristics of the OFET with the SPM treatment were stable even after 44days storage in air under room illumination without any passivation. Moreover, the drain current reduction due to threshold voltage (Vth) shift under continuous application of gate voltage quickly recovered toward the original value with unloading of gate voltage.

Evaluation of the Vapor and Chemical Sensing Mechanism for Pentacene Field Effect Transistors

2010 ◽  
Vol 1253 ◽  
Author(s):  
Davianne A Duarte ◽  
Deepak Sharma ◽  
Brian Cobb ◽  
Ananth Dodabalapur
Keyword(s):  
Field Effect Transistors ◽  
High Mobility ◽  
Drain Current ◽  
Channel Length ◽  
Organic Thin Film ◽  
Lower Mobility ◽  
And Shifts ◽  
Increasing Temperature ◽  
Mobility Device ◽  
Alcohol Testing

AbstractProperties such as semicondutor film grain size, morphology, and channel length are known to effect the sensing response in pentacene based organic thin film transistors (OTFTs). The sensing behavior for low and high mobility pentacene devices are reported here exhibiting different temperature dependent behaviors. The lower mobility OTFT exhibits an expected thermally activated response during alcohol testing with an increasing mobility with temperature along with a decreasing mobility at each temperature for increasing concentration. The higher mobility device exhibits a decrease in mobility with increasing temperature along with a decrease in mobility with increasing concentration at each temperature. In both sets of devices, the polar analyte produced reductions in drain current and shifts in threshold voltage.

A Comparative Investigation of a Pentacene Layer on Gold and PMMA in Bottom-Contact Pentacene Thin Film Transistors

2013 ◽  
Vol 802 ◽  
pp. 27-31 ◽  
Author(s):  
Tossapol Tippo ◽  
Chanchana Thanachayanont ◽  
Hideki Nakajima ◽  
Prayoon Songsiriritthigul ◽  
Micheal Hietschold ◽  
...  
Keyword(s):  
Thin Film Transistors ◽  
Thermal Evaporation ◽  
Gate Dielectric ◽  
Comparative Investigation ◽  
Channel Length ◽  
Deposition Condition ◽  
Bottom Contact ◽  
Structure Morphology ◽  
Substrate Temperatures

This study demonstrates an attempt to fabricate the 25 µm channel-length bottom-contact pentacene TFTs using thermal evaporation through shadow mask technique and to investigate crystal structure, morphology and electronic structure of the pentacene layer deposited at the same time on gold (Au) source-drain electrodes and Poly(methyl methacrylate) (PMMA) gate-dielectric of the TFTs. The pentacene layers with thicknesses of 50 nm were deposited at the evaporation rates of 0.1, 0.5, 1.0 and 1.5 nm/min at substrate temperatures of 60 °C. These conditions were employed with and without preheating at 80 °C before deposition. Preheating at 80 °C was found to improve quality of the pentacene film on the PMMA gate-dielectric. Using the deposition rate of 1 nm/min and the substrate temperature of 60 °C, best performance of TFTs were obtained. At this deposition condition, pentacene film work function was found to be higher on the Au source-drain electrodes than on the PMMA gate-dielectric.

scholarly journals Relationship of drain induced barrier lowering and top/bottom gate oxide thickness in asymmetric junctionless double gate MOSFET

2021 ◽  
Vol 11 (1) ◽  
pp. 232
Author(s):  
Hakkee Jung
Keyword(s):  
Threshold Voltage ◽  
Gate Voltage ◽  
Drain Current ◽  
Gate Oxide ◽  
Channel Length ◽  
Double Gate ◽  
Static Feedback ◽  
Silicon Thickness ◽  
Relationship Of ◽  
Bottom Gate

The relationship of drain induced barrier lowering (DIBL) phenomenon and channel length, silicon thickness, and thicknesses of top and bottom gate oxide films is derived for asymmetric junctionless double gate (JLDG) MOSFETs. The characteristics between the drain current and the gate voltage is derived by using the potential distribution model to propose in this paper. In this case, the threshold voltage is defined as the corresponding gate voltage when the drain current is (W/L) × 10-7 A, and the DIBL representing the change in the threshold voltage with respect to the drain voltage is obtained. As a result, we observe the DIBL is proportional to the negative third power of the channel length and the second power of the silicon thickness and linearly proportional to the geometric mean of the top and bottom gate oxide thicknesses, and derive a relation such as DIBL =25.15ηL_g^(-3) t_si^2 √(t_ox1∙t_ox2 ), where η is a static feedback coefficients between 0 and 1. The η is found to be between 0.5 and 1.0 in this model. The DIBL model of this paper has been observed to be in good agreement with the result of other paper, so it can be used in circuit simulation such as SPICE.

Material Limitations for the Development of High Performance SiC NWFETs

2012 ◽  
Vol 711 ◽  
pp. 70-74
Author(s):  
Konstantinos Zekentes ◽  
Konstantinos Rogdakis ◽  
Edwige Bano
Keyword(s):  
High Performance ◽  
Field Effect Transistors ◽  
Schottky Contact ◽  
Electrical Characterization ◽  
Drain Current ◽  
High Electron ◽  
High Electron Concentration ◽  
Contact Devices ◽  
Contact Barrier

Back-gated field effect transistors (FETs) based on 3C-SiC nanowire (NW) were fabricated and the electrical characterization revealed devices with either ohmic or rectifying contacts leading to two different operation modes. The transistors with ohmic-like contacts manifest very weak gating effect and the device switching off is not achievable even for high negative gate voltages due to the high electron concentration along the nanowires. In contrast, the devices with Schottky contact barrier at Source / Drain regions demonstrate a well determined switching off and in general better performance thanks to the modulation of the drain current through the control of Schottky barriers transparency at the source and drain regions. Nevertheless, ohmic contact devices are expected to demonstrate even better performance if the NW material quality as well as the quality of the interface with the gate oxide is substantially improved.

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