scholarly journals Insight into the semiconducting performance of tetraphenyldipyranylidene derivatives in organic field-effect transistors

Author(s):  
Samira Naserian ◽  
Mohammad Izadyar ◽  
Foroogh Arkan

In this paper, Tetraphenyldipyranylidene (DPPh), a large quinoidal planar π-conjugated heterocyclic, was considered as primary organic molecule in organic field effect transistors (OFETs). Electron-withdrawing atoms such as F, Cl, and Br were attached to the H-atoms of four peripheral phenyl groups of para-positions relative to the O-atoms of DPPh. Density functional theory (DFT) calculations at the M06-2X/6-311G++ (d,p) level were performed. The influences of the different electron-withdrawing atoms such as F, Cl, and Br on the electronic and optical properties, charge transport parameters, and charge carrier mobility were investigated. The absorption and emission spectra of the DPPh and its derivatives were theoretically simulated in OFETs. The simulated spectra show an intense peak in the visible region (400-650 nm), in which the highest adsorption/emission intensity is related to DPPh-Br. Moreover, the charge injection energy barrier of DPPh and its derivatives were calculated by considering Pt as the source electrode. Based on the results, a greater hole transport is predicted than the electron transport. Moreover, the obtained ratio of the hole/electron mobility and the theoretical correlations between the charge transport parameters of monomers and dimers show that the insertion of the electron-withdrawing atoms in the DPPh structure is a promising strategy to have an ambipolar or n-type semiconductor, too. The obtained results show that introducing electron-withdrawing atoms at the para-position of the DPPh improves the hole/electron injection and transport process in the OFET devices. Finally, DPPh-Br shows a great performance in comparison with the substituted F and Cl atoms in the OFETs devices.

2010 ◽  
Vol 1270 ◽  
Author(s):  
Mujeeb Ullah ◽  
Andrey K. Kadashchuk ◽  
Philipp Stadler ◽  
Alexander Kharchenko ◽  
Almantas Pivrikas ◽  
...  

AbstractThe critical factor that limits the efficiencies of organic electronic devices is the low charge carrier mobility which is attributed to disorder in organic films. In this work we study the effects of active film morphology on the charge transport in Organic Field Effect Transistors (OFETs). We fabricated the OFETs using different substrate temperature to grow different morphologies of C60 films by Hot Wall Epitaxy. Atomic Force Microscopy images and XRD results showed increasing grain size with increasing substrate temperature. An increase in field effect mobility was observed for different OFETs with increasing grain size in C60 films. The temperature dependence of charge carrier mobility in these devices followed the empirical relation named as Meyer-Neldel Rule and showed different activation energies for films with different degree of disorder. A shift in characteristic Meyer-Neldel energy was observed with changing C60 morphology which can be considered as an energetic disorder parameter.


2008 ◽  
Vol 63 (9) ◽  
pp. 591-595 ◽  
Author(s):  
Elizabeth von Hauff ◽  
Nicolas Spethmann ◽  
Jürgen Parisi

A gated four probe measurement technique to isolate contact resistances in field effect measurementson disordered organic semiconductors was investigated. Organic field effect transistors (OFETs) were prepared with two additional electrodes in the contact geometry protruding into the source-drain channel to monitor the variation in potential across the channel. Two high impedance electrometers were used to determine the potential at the contacts. This technique allows to directly determine the magnitude of the parasitic contact resistances between metal contact and organic semiconductor from the drop in potential at the contact regions. The effects of contact resistances, which can falsify measurements on bulk transport parameters such as the field effect mobility, can be then eliminated during material characterization. Additionally, the temperature and electric field dependence of the contact resistances offers valuable information about the charge injection and extraction processes between metal and organic semiconductor. The effects of the four probe geometry, specifically the effect of the channel electrodes on the current-voltage characteristics, of hole transport in a polythiophene (P3HT) OFET with Au contacts were investigated and found not to influence device performance, except at currents « 1 nA. The IV characteristics were shown to follow the expected FET behaviour. From the variation in potential along the channel it was found that contact resistances at the source contact (charge injecting contact) are minimal while contact resistances at thedrain contact (charge extracting contact) are significant, resulting in a much lower effective sourcedrain voltage than that applied to the device.


2021 ◽  
Vol 13 (7) ◽  
pp. 8631-8642
Author(s):  
Tomoya Taguchi ◽  
Fabio Chiarella ◽  
Mario Barra ◽  
Federico Chianese ◽  
Yoshihiro Kubozono ◽  
...  

2012 ◽  
Vol 101 (24) ◽  
pp. 243302 ◽  
Author(s):  
Yasuhiro Mashiko ◽  
Dai Taguchi ◽  
Martin Weis ◽  
Takaaki Manaka ◽  
Mitsumasa Iwamoto

2020 ◽  
Vol 8 (44) ◽  
pp. 15759-15770
Author(s):  
Alexandra Harbuzaru ◽  
Iratxe Arrechea-Marcos ◽  
Alberto D. Scaccabarozzi ◽  
Yingfeng Wang ◽  
Xugang Guo ◽  
...  

Different charge transport mechanisms at the device interface are found for a series of ladder-type semiconductors with increasing chain length.


2015 ◽  
Vol 51 (3) ◽  
pp. 503-506 ◽  
Author(s):  
Gaole Dai ◽  
Jingjing Chang ◽  
Wenhua Zhang ◽  
Shiqiang Bai ◽  
Kuo-Wei Huang ◽  
...  

Two stable dianthraceno[a,e]pentalenes were synthesized and DAP2 exhibited a high charge carrier mobility of 0.65 cm2 V−1 s−1 due to its dense packing.


Sign in / Sign up

Export Citation Format

Share Document