Nucleobases thin films deposited on nanostructured transparent conductive electrodes for optoelectronic applications

AbstractEnvironmentally-friendly bio-organic materials have become the centre of recent developments in organic electronics, while a suitable interfacial modification is a prerequisite for future applications. In the context of researches on low cost and biodegradable resource for optoelectronics applications, the influence of a 2D nanostructured transparent conductive electrode on the morphological, structural, optical and electrical properties of nucleobases (adenine, guanine, cytosine, thymine and uracil) thin films obtained by thermal evaporation was analysed. The 2D array of nanostructures has been developed in a polymeric layer on glass substrate using a high throughput and low cost technique, UV-Nanoimprint Lithography. The indium tin oxide electrode was grown on both nanostructured and flat substrate and the properties of the heterostructures built on these two types of electrodes were analysed by comparison. We report that the organic-electrode interface modification by nano-patterning affects both the optical (transmission and emission) properties by multiple reflections on the walls of nanostructures and the electrical properties by the effect on the organic/electrode contact area and charge carrier pathway through electrodes. These results encourage the potential application of the nucleobases thin films deposited on nanostructured conductive electrode in green optoelectronic devices.

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Direct measurement of the thermoelectric properties of electrochemically deposited Bi2Te3 thin films

Scientific Reports ◽

10.1038/s41598-020-74887-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jose Recatala-Gomez ◽

Pawan Kumar ◽

Ady Suwardi ◽

Anas Abutaha ◽

Iris Nandhakumar ◽

...

Keyword(s):

Thin Films ◽

Thermoelectric Properties ◽

Bismuth Telluride ◽

Indium Tin Oxide ◽

Seed Layer ◽

Room Temperature ◽

Low Cost ◽

Temperature Dependent ◽

Temperature Heat ◽

Electrochemically Deposited

Abstract The best known thermoelectric material for near room temperature heat-to-electricity conversion is bismuth telluride. Amongst the possible fabrication techniques, electrodeposition has attracted attention due to its simplicity and low cost. However, the measurement of the thermoelectric properties of electrodeposited films is challenging because of the conducting seed layer underneath the film. Here, we develop a method to directly measure the thermoelectric properties of electrodeposited bismuth telluride thin films, grown on indium tin oxide. Using this technique, the temperature dependent thermoelectric properties (Seebeck coefficient and electrical conductivity) of electrodeposited thin films have been measured down to 100 K. A parallel resistor model is employed to discern the signal of the film from the signal of the seed layer and the data are carefully analysed and contextualized with literature. Our analysis demonstrates that the thermoelectric properties of electrodeposited films can be accurately evaluated without inflicting any damage to the films.

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Structural and Electrical Properties of Sprayed In2S3 Films on ITO/Glass Substrate

10.21203/rs.3.rs-481705/v1 ◽

2021 ◽

Author(s):

J. Koaib ◽

N. Bouguila ◽

M. Kraini ◽

I. Halidou ◽

K. Khirouni ◽

...

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Indium Tin Oxide ◽

Glass Substrate ◽

Spray Pyrolysis Technique ◽

Electrical Conductance ◽

Average Crystallite Size ◽

Chemical Spray Pyrolysis ◽

Electrical Equivalent Circuit ◽

Ito Glass

Abstract In2S3 thin films were grown on indium tin oxide (ITO) glass substrate by chemical spray pyrolysis technique at 360°C. The structural analysis of the deposited films shows a combination of tetragonal and cubic structures. The average crystallite size is about 25 nm. The electrical properties of In2S3 thin films have been investigated in a wide frequency (40Hz-100MHz) and temperature (400 K-660 K) ranges.We find that the electrical conductance of the In2S3 thin films is frequency and temperature dependent. The dc conductance shows a semi-conductor behavior for In2S3 films over the explored range of temperature and it follows the Arrhenius law with different activation energies. The variation of ac conductance and the frequency exponent `s’ are explained by the correlated barrier hopping (CBH) model. The Nyquist plots of impedance exhibit semicircle arcs and an electrical equivalent circuit has been suggested to interpret the impedance results.

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Indium-tin oxide thin films deposited at room temperature on glass and PET substrates: Optical and electrical properties variation with the H2–Ar sputtering gas mixture

Applied Surface Science ◽

10.1016/j.apsusc.2015.03.096 ◽

2015 ◽

Vol 344 ◽

pp. 217-222 ◽

Cited By ~ 18

Author(s):

L. Álvarez-Fraga ◽

F. Jiménez-Villacorta ◽

J. Sánchez-Marcos ◽

A. de Andrés ◽

C. Prieto

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Tin Oxide ◽

Indium Tin Oxide ◽

Room Temperature ◽

Gas Mixture ◽

Optical And Electrical Properties ◽

Oxide Thin Films

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Fabrication of Organic Small Molecular Thin Films based on Ultrasonic Spray-Assisted Vapor-Deposition Method

MRS Proceedings ◽

10.1557/opl.2012.18 ◽

2012 ◽

Vol 1400 ◽

Author(s):

Jinchun Piao ◽

Shigetaka Katori ◽

Takumi Ikenoue ◽

Shizuo Fujita

Keyword(s):

Thin Films ◽

Indium Tin Oxide ◽

Vapor Deposition ◽

Low Cost ◽

Device Fabrication ◽

Deposition Method ◽

Material Loss ◽

Good Surface ◽

Low Leakage ◽

Molecular Thin Films

ABSTRACTSmall molecular thin films using solution-based method is a challengeable subject in organic optical and electronic devices. In our previous research, we successfully deposited aluminum tris(8-hydroxyquinoline) (Alq3) films on glass substrate. In this paper, aiming at future exploration of electroluminescent devices, we deposited N, N ’-Bis(3-methylphenyl)-N,N’- diphenylbenzidine) (TPD) films on indium-tin-oxide (ITO) substrates using the vapor-deposition method. Photoluminescence characteristics evidenced the actual formation of TPD thin films. Together with the good surface morphology and low leakage current of the films, the results are promising for actual device fabrication at low cost and low material loss.

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On the UV-light-induced Desorption/Adsorption Mechanism of Atmospheric Species in Solution-processed Zinc Oxide Thin Films

MRS Advances ◽

10.1557/adv.2019.59 ◽

2019 ◽

Vol 4 (2) ◽

pp. 111-117

Author(s):

José Bruno Cantuária ◽

Giovani Gozzi ◽

Lucas Fugikawa Santos

Keyword(s):

Thin Films ◽

Zinc Oxide ◽

Electrical Properties ◽

Uv Light ◽

Atmospheric Oxygen ◽

Low Cost ◽

Environmental Parameters ◽

Zno Films ◽

Desorption Rate ◽

Transparent Semiconductor

AbstractZinc oxide (ZnO) is a n-type transparent semiconductor which can be processed by low cost techniques (such as spray-pyrolysis and spin-coating) and can be applied as the active layer of thin-films transistors (TFTs). The electrical properties of ZnO films are strongly affected when the device is exposed to room conditions and/or UV-light, suggesting possible applications as UV or/and gas sensors. Atmospheric oxygen molecules adsorbed on ZnO surface act as charge traps, decreasing the material conductivity. The incidence of UV-light causes an increase of the material conductivity due to the photogeneration of electron-hole pairs via direct band-to-band transitions (classic photoconductivity process) and due to the desorption of oxygen molecules, which presents a relatively slower response and is a less understood mechanism. In the current paper, we study the influence of environmental parameters, such as temperature, humidity and UV-light intensity, on the electrical properties of spin-coated ZnO thin films to understand the role of the desorption mechanism on the photoconductivity process. The analysis of the device current vs. time curves shows the existence of two light-induced desorption mechanisms: i) one which increases the electrical conductivity of the ZnO film (desorption-like process) and ii) a second one which decreases the conductivity (adsorption-like process). A Plackett-Burman design of experiment (DOE) was used to study the influence of characterization factors like UV intensity, temperature and humidity on electrical parameters obtained from the experimental curves. We observed that the desorption-like process is a first order mechanism, exhibiting desorption rate proportional to n(t), where n(t) represents the adsorbate concentration as a function of the time, whereas the adsorption-like mechanism exhibits a desorption rate proportional to the forth power of n(t).

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