Dry shear aligning: a simple and versatile method to smooth and align the surfaces of carbon nanotube thin films

AbstractWe propose the application of ZnO:X (X = Li, Mg, N, In, Al, Mn, Gd, Yb etc.) films for a monolithic Optical Integrated Circuit (OIC). Since ZnO exhibits excellent piezoelectric effect and has also electro-optic and nonlinear optic effects and the thin films are easily obtained, it has been studied as one of the important thin film wave guide materials especially for an acoustooptic device[1]. In terms of electro-optic and nonlinear optic effects, however, LiNbO3 or LiTaO3 is superior to ZnO. The most important issue of thin film waveguide using such ferroelectrics is optical losses at the film/substrate interface and the film surface, because the process window to control the surface morphology is very narrow due to their high deposition temperature. Since ZnO can be grown at extremely low temperature, the roughness at the surface and the interface is expected to be minimized. This is the absolute requirement especially for waveguide using a blue or ultraviolet laser. Recently, lasing at the wavelength of ultraviolet, ferroelectric and antiferromagnetic behaviors of ZnO doped with various exotic elements (exotic doping) have been reported. This paper discusses the OIC application of ZnO thin films doped with exotic elements.

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Development of the Structural, Optical, and Electrical Properties of PEDOT:PSS Conducting Polymer Thin Film for Energy Applications

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.902.65 ◽

2021 ◽

Vol 902 ◽

pp. 65-70

Author(s):

Samar Aboulhadeed ◽

Mohsen Ghali ◽

Mohamad M. Ayad

Keyword(s):

Thin Film ◽

Thin Films ◽

Electrical Properties ◽

Conducting Polymer ◽

Film Surface ◽

Volume Ratio ◽

Transport Layer ◽

Electron Transport Layer ◽

Optical And Electrical Properties ◽

Energy Applications

We report on a development of the structural, optical and electrical properties of poly (3,4-ethylenedioxythiophene)-poly (styrenesulfonate) (PEDOT:PSS) conducting polymer thin films. The PEDOT:PSS thin films were deposited by a controlled thin film applicator and their physical properties were found to be effectively modified by isopropanol. The deposited films were investigated by several techniques including XRD, UV–Vis, SPM and Hall-effect. Interestingly, by optimizing the PEDOTS:PSS/ISO volume ratio (v:v), we find that the film charge carriers type can be switched from p to n-type with a high bulk carriers concentration reaching 6×1017 cm-3. Moreover, the film surface roughness becomes smoother and reaching a small value of only 1.9 nm. Such development of the PEDOT:PSS film properties makes it very promising to act as an electron transport layer for different energy applications.

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Positioning of the Precursor Gas Inlet in an Atmospheric Dielectric Barrier Reactor, and its Effect on the Quality of Deposited TiOx Thin Film Surface

Acta Polytechnica ◽

10.14311/1767 ◽

2013 ◽

Vol 53 (2) ◽

Author(s):

Jan Píchal ◽

Julia Klenko

Keyword(s):

Thin Film ◽

Thin Films ◽

Dielectric Barrier Discharge ◽

Atmospheric Pressure ◽

Barrier Discharge ◽

Film Surface ◽

Dielectric Barrier ◽

Thin Film Surface ◽

Atmospheric Dielectric Barrier Discharge

Thin film technology has become pervasive in many applications in recent years, but it remains difficult to select the best deposition technique. A further consideration is that, due to ecological demands, we are forced to search for environmentally benign methods. One such method might be the application of cold plasmas, and there has already been a rapid growth in studies of cold plasma techniques. Plasma technologies operating at atmospheric pressure have been attracting increasing attention. The easiest way to obtain low temperature plasma at atmospheric pressure seems to be through atmospheric dielectric barrier discharge (ADBD). We used the plasma enhanced chemical vapour deposition (PECVD) method applying atmospheric dielectric barrier discharge (ADBD) plasmafor TiOx thin films deposition, employing titanium isopropoxide (TTIP) and oxygen as reactants, and argon as a working gas. ADBD was operated in filamentary mode. The films were deposited on glass. We studied the quality of the deposited TiOx thin film surface for various precursor gas inlet positions in the ADBD reactor. The best thin films quality was achieved when the precursor gases were brought close to the substrate surface directly through the inlet placed in one of the electrodes.High hydrophilicity of the samples was proved by contact angle tests (CA). The film morphology was tested by atomic force microscopy (AFM). The thickness of the thin films varied in the range of (80 ÷ 210) nm in dependence on the composition of the reactor atmosphere. XPS analyses indicate that composition of the films is more like the composition of TiOxCy.

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Effect of RF Power on the Properties of Sputtered-CuS Thin Films for Photovoltaic Applications

Energies ◽

10.3390/en13030688 ◽

2020 ◽

Vol 13 (3) ◽

pp. 688 ◽

Cited By ~ 1

Author(s):

Donghyeok Shin ◽

SangWoon Lee ◽

Dong Ryeol Kim ◽

Joo Hyung Park ◽

Yangdo Kim ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Binding Energy ◽

Indium Tin Oxide ◽

Short Circuit ◽

Film Surface ◽

Binding Energies ◽

Tin Sulfide ◽

Rf Power ◽

Deposition Power

Copper sulfide (CuS) thin films were deposited on a glass substrate at room temperature using the radio-frequency (RF) magnetron-sputtering method at RF powers in the range of 40–100 W, and the structural and optical properties of the CuS thin film were investigated. The CuS thin films fabricated at varying deposition powers all exhibited hexagonal crystalline structures and preferred growth orientation of the (110) plane. Raman spectra revealed a primary sharp and intense peak at the 474 cm−1 frequency, and a relatively wide peak was found at 265 cm−1 frequency. In the CuS thin film deposited at an RF power of 40 W, relatively small dense particles with small void spacing formed a smooth thin-film surface. As the power increased, it was observed that grain size and grain-boundary spacing increased in order. The binding energy peaks of Cu 2p3/2 and Cu 2p1/2 were observed at 932.1 and 952.0 eV, respectively. Regardless of deposition power, the difference in the Cu2+ state binding energies for all the CuS thin films was equivalent at 19.9 eV. We observed the binding energy peaks of S 2p3/2 and S 2p1/2 corresponding to the S2− state at 162.2 and 163.2 eV, respectively. The transmittance and band-gap energy in the visible spectral range showed decreasing trends as deposition power increased. For the CuS/tin sulfide (SnS) absorber-layer-based solar cell (glass/Mo/absorber(CuS/SnS)/cadmium sulfide (CdS)/intrinsic zinc oxide (i-ZnO)/indium tin oxide (ITO)/aluminum (Al)) with a stacked structure of SnS thin films on top of the CuS layer deposited at 100 W RF power, an open-circuit voltage (Voc) of 115 mA, short circuit current density (Jsc) of 9.81 mA/cm2, fill factor (FF) of 35%, and highest power conversion efficiency (PCE) of 0.39% were recorded.

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Parametric Study of Nanostructure Variations on the Macroscopic Thermal and Electrical Behavior of Neat CNT Thin Film Networks

Volume 11: Nano and Micro Materials, Devices and Systems; Microsystems Integration ◽

10.1115/imece2011-63678 ◽

2011 ◽

Author(s):

Nikhil A. Ashtekar ◽

David A. Jack

Keyword(s):

Thin Film ◽

Thin Films ◽

Electrical Conductivity ◽

Sensitivity Analysis ◽

Carbon Nanotube ◽

Probability Distribution ◽

Electrical Response ◽

Electrical Behavior ◽

Commercial Applications ◽

Nanotube Chirality

Carbon nanotube thin films are considered by many researchers as a material for the future in many electrical and thermal applications, but a lack of systematic physics-based modeling approaches to quantify the bulk thermal and electrical response due to nanostructure variations makes employing these thin films difficult for commercial applications. In this work we employ the previously presented 3D physics-based computational model for characterizing the bulk thermal and electrical response of a neat carbon nanotube thin film network involving stochastic distributions of length, diameter, chirality, orientation and values of intercontact resistivity obtained from the literature. The model is employed to test the sensitivity of bulk thermal and electrical conductivity on stochastic variations in the nanostructure parameters. We examine the sensitivity of the thin film networks to the experimentally obtained Weibull probability distribution for length and diameter. Additionally, we present a study to quantify the macroscopic conductivity dependence on the nanotube chirality ratio. Through these studies we present an approach that is very generic and can be used for the sensitivity analysis due to variations within the nanostructure.

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Imaging of Chemical Reactions Using a Terahertz Chemical Microscope

Photonics ◽

10.3390/photonics6010010 ◽

2019 ◽

Vol 6 (1) ◽

pp. 10 ◽

Cited By ~ 3

Author(s):

Toshihiko Kiwa ◽

Tatsuki Kamiya ◽

Taiga Morimoto ◽

Kentaro Fujiwara ◽

Yuki Maeno ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Chemical Reactions ◽

Field Effect ◽

Film Surface ◽

Experimental Setup ◽

Substrate Side ◽

Surface Field ◽

Silicon Based ◽

Si Thin Film

This study develops a terahertz (THz) chemical microscope (TCM) that visualizes the distribution of chemical reaction on a silicon-based sensing chip. This chip, called the sensing plate, was fabricated by depositing Si thin films on a sapphire substrate and thermally oxidizing the Si film surface. The Si thin film of the sensing plate was irradiated from the substrate side by a femtosecond laser, generating THz pulses that were radiated into free space through the surface field effect of the Si thin film. The surface field responds to chemical reactions on the surface of the sensing plate, changing the amplitude of the THz pulses. This paper first demonstrates the principle and experimental setup of the TCM and performs the imaging and measurement of chemical reactions, including the reactions of bio-related materials.

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SYNTHESIS OF IODINE DOPED n-BMA THIN FILMS VIA PLASMA POLYMERIZATION TECHNIQUE: EFFECT ON OPTICAL PROPERTIES

Surface Review and Letters ◽

10.1142/s0218625x19501336 ◽

2019 ◽

Vol 27 (04) ◽

pp. 1950133

Author(s):

RAHIMA NASRIN ◽

HUMAYUN KABIR ◽

A. H. BHUIYAN

Keyword(s):

Thin Film ◽

Thin Films ◽

Optical Properties ◽

Plasma Polymerization ◽

Film Surface ◽

Microscopic Analysis ◽

Butyl Methacrylate ◽

Root Mean Square Roughness ◽

Iodine Doping ◽

Thin Film Surface

In order to understand the variation of surface morphology and optical properties due to modification, an attempt has been made to synthesize iodine-doped n-butyl methacrylate thin films through plasma polymerization technique. Field emission scanning electron microscope images displayed that the surface of the modified plasma polymerized n-butyl methacrylate (PPnBMA) thin films became smooth after iodine doping. Atomic force microscopic analysis reveals that with increasing doping time from 0[Formula: see text]min to 60[Formula: see text]min the surface root-mean-square roughness value is decreased from 0.68[Formula: see text]nm to 0.51[Formula: see text]nm, which suggests that roughness of the PPnBMA thin film surface quite improved due to iodine doping. UV-Vis absorption spectroscopic analyses exhibited that iodine doping noticeably decreased both the direct and indirect energy bandgap values of PPnBMA thin film. The effect of doping by iodine on absorption coefficient, extinction coefficient, etc. of these thin films have been also discussed.

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