Electrical Properties Of Films Research Articles

Tailorable ITO thin films for tunable microwave photonic applications

Tunability is a fundamental prerequisite for functional devices and forms the backbone of reconfigurable microwave photonic (MWP) signal processors. In this paper, we explore the use of indium tin oxide (ITO) thin films, notable for their combination of optical transparency and electrical conductivity, to provide tunability for integrated MWP devices. We study the impacts of post-thermal annealing on the structural, electrical, and optical properties of ITO films. The annealed ITO microheater maintains a low total insertion loss of just 0.1 dB while facilitating the tunability of the microring across the entire free spectral range (FSR) using less than half the voltage required by its non-annealed counterpart. Furthermore, the post-annealed ITO film exhibits a 30% improvement in response time, enhancing its performance as an active voltage-controlled microheater. Leveraging this advantage, we employed the post-annealed device to demonstrate continuous tunable radio frequency (RF) phase shifts from 0–330° across a frequency range spanning 15 GHz to 40 GHz with only 5.58 mW of power. The flexibility in modifying the ITO thin film properties effectively bridges the gap between achieving low-loss and high-speed thermo-optic based microheaters.

Exploring the impact of antimony trisulfide (Sb2S3) doping on the optoelectronic functionality of hybrid CH3NH3PbI3 perovskite layers and solar cells

In this study, we present the effect of doping with antimony trisulfide (Sb2S3) nanobare on the electrical, optical, structural, and morpholigcal properties of CH3NH3 PbI3 perovskite thin films. Doped with Sb2S3 nanobare, the thin coatings demonstrated an exceptionally high degree of purity, featuring a tetragonal phase within its single-phase structure. This allowed for the creation of (110) textured CH3NH3PbI3 films, which comprised micrometer-sized grains arranged in a vertical direction across the entire film thickness and featured high crystallinity. Additionally, the CH3NH3PbI3 perovskites films exhibited significant optical absorption at appropriate energy levels and exhibited a high gachin rate of photons. Substance doping methods that can optimize the morphology of the perovskite active layer with large granules are exceedingly desirable in order to reduce charge carrier recombination. The synthesis of perovskite films with dimensions on the order of microns can be achieved by incorporating a regulated quantity of Sb2S3 nanobare into the precursor solution. The incorporation of these textured CH3NH3PbI3:Sb2S3 nanobare films significantly enhanced the power conversion efficiency (PCE) of the perovskite solar cells. The solar cell device configuration utilized in this investigation is as follows: glass/FTO/TiO2/CH3NH3PbI3:Sb2S3 nanobars/spiro-OMeTAD/Au. By employing Sb2S3 nanobars at a concentration of 9 mg/mL, we successfully attained an exceptional power conversion efficiency of 15.87 %. The resulting values for these parameters include an open-circuit voltage VOC of 1.09 V, a short-circuit current density JSC of 21.15 mA/cm2, and a fill factor FF of 68.87 %.

Correlation between structural, morphological, and electrical transport properties of nano-dimensional Tellurium thin film by low energy ion beam irradiation

Tellurium (Te), an emerging semiconductor material, exhibits intriguing physical properties in low-dimensional forms. This study investigates the structural, morphological, and transport properties of low-dimensional Te thin film deposited by physical vapor deposition after 400 keV Kr2+ ion irradiation with varying fluences of 1 × 1013, 5 × 1013, and1 × 1014 ions-cm−2. The X-ray diffraction (XRD) pattern reveals the hexagonal phase of pristine Te. As ion fluence increases, intensity of the XRD peaks decreases and the full-width half maxima (FWHM) increases, indicating a reduction in crystallinity. The intensity of the Raman peak decreases upon irradiation, resulting in a red shift in the spectra of the irradiated sample. The evolution of morphology at different fluences has been examined with atomic force microscopy (AFM) measurements. The results indicate the segregation of grains and an increase in root mean square (RMS) roughness from 2.59 pm to 5.11 pm with ion fluence up to 5 × 1013 ions-cm−2. At the highest fluence, i.e., 1 × 1014 ions-cm−2, there is an agglomeration of grains, and hence a decrease in RMS roughness to 3.92 pm is observed. The DC resistivity measurement indicates the semiconducting nature of all films. Additionally, this measurement signifies the rapid decrease in activation energy at both band-to-band conduction and nearest neighbour hopping (NNH) conduction. Following irradiation, Hall measurement demonstrates a decrease in the concentration of charge carriers and an increase in resistivity due to scattering originating from grain boundaries. However, when the fluence is increased to 1 × 1014 ions-cm−2, there is a reduction in resistivity and an increase in carrier concentration with enhanced Hall mobility in comparison to pristine Te. Therefore, this study showcases that low-energy ion irradiation has a significant impact on the modification of the structure, morphology, and electrical transport properties of semiconducting Te thin film.

Preparation, characterization, and electrical properties of PVDF-ZnO nanocomposite thin films

Preparation, characterization, and electrical properties of PVDF-ZnO nanocomposite thin films

Improved electrical transport properties of La0.7Ca0.3−xKxMnO3 (0.0 ≤ x ≤ 0.3) films grown on La0.3Sr0.7Al0.65Ta0.35O3 (00l) substrates by sol–gel spin coating method

Herein, La0.7Ca0.3−xKxMnO3 (LCKMO) films with highly oriented growth were prepared on La0.3Sr0.7Al0.65Ta0.35O3 (00l) substrates by sol–gel spin coating method. Comprehensive analysis of microstructure, surface morphology, ion valence, and electrical transport properties of LCKMO films indicates that the substitution of K+ ions for Ca2+ ions increased the ratio of Mn4+/(Mn3+ + Mn4+), narrowed the one electron bandwidth, and enhanced double exchange mechanism and electron–lattice coupling. Moreover, the doping of K+ ions induced the dense and uniform conical-structured growth of grains on the surface of the films. Results demonstrated that at x = 0.1, LCKMO film exhibited the maximum TCR of 17.84% K−1 at 253.07 K, which was 31.76% higher than that of previously reported La1−x−yCaxKyMnO3 ceramic with the highest TCR. Further theoretical insights into the effects of Ca/K co-doping on electrical transport properties were supplemented.

The structural, optical, electrical and radiation shielding properties of Co-doped ZnO thin films

Co:ZnO thin films are promising due to the similar ionic radii of cobalt and ZnO, and their potential for carrier spin injection, transfer, and detection. This study aims to investigate the structural, optical, electrical, and radiation shielding properties of Co-doped zinc oxide (Co:ZnO) thin films for potential applications in various fields such as semiconductors, solar cells, spintronics, and radiation shielding. The effect of commercially available Cobalt acetate tetrahydrate and Cobalt complex (Co with conjugated NN ligand) as cobalt additives on the synthesis of ZnO thin films is compared, aiming to discern their respective impacts. The dopants are incorporated in 2, 4, and 6 wt.%, employing the sol-gel spin coating method. Cobalt effectively served as a substitution dopant, preserving the wurtzite crystal structure, and the cobalt complex additive demonstrated a superior enhancement of the electronic band gap compared to the commercial cobalt additive. Applying cobalt complex additive as Co precursor resulted in ZnO:Co films with a superior enhancement of the electronic band gap of 2.84 - 3.00 eV compared to cobalt acetate precursor (2.67-2.84 eV). With the introduction of Cobalt, there is a notable change in the electrical conductivity, showcasing a decrease from 1.5x10-7 to 2.11x10-10 (S/cm). Also, radiation shielding parameters were experimentally measured in the energy range of 186.1-1764.5 keV within the scope of gamma ray spectral analysis. Exposure buildup factors (EBF) in the energy range of 15-15000 keV were calculated up to 1-40 mean free path (mfp). Mass stopping power (MSP) and projected range values (PR) for nuclear safety applications were calculated for protons and alpha particles using the SRIM code. Thin film thicknesses were determined by using Lambert-Beer law. It was observed that the thin film thicknesses obtained from gamma spectrometry (2.090-2.628 μm) and SEM (2.157-2.725 μm) were compatible with each other.

Effect of Mo and W co-doping on optical, morphological, electrical and electrochemical properties of Co3O4 thin film

Effect of Mo and W co-doping on optical, morphological, electrical and electrochemical properties of Co3O4 thin film

Controlling Fluorination Density of Soluble Polyimide Gate Dielectrics and its Influence on Organic Crystal Growth and Device Operational Stability.

Fluorinated polyimides (PIs) are among the most promising candidates for gate dielectric materials in organic electronic devices because of their solution processability and outstanding chemical, mechanical, and thermal stabilities. Additionally, fluorine (F) substitution improves the electrical properties of PI thin films, such as enhanced dielectric properties and reduced surface trap densities. However, the relationship between the fluorination density of PIs and crystal growth modes of vacuum-deposited conjugated molecules on PI thin films, which is directly related to the lateral charge transport along the PI-organic semiconductor interface, has not been systematically studied. Herein, five different soluble PIs with different F densities were synthesized, and the correlation between fluorination and thin-film properties was systematically investigated. Not only were their dielectric properties modulated, but the growth modes of the organic molecules deposited on the PI thin films also changed with increasing surface F density. This phenomenon was observed by both surface and crystallographic analyses, which resulted in extremely high operational stability of field-effect transistors and the successful fabrication of organic complementary circuits. We believe that the correlation between PI backbone fluorination and its thin-film properties will provide practical insights into the material design based on controlled molecular directed surface assembly on fluorinated polymer dielectrics.

Morphological, Optical, and Electrical Studies of PVD CdTe Thin Films for Photovoltaic Applications

Nano-crystalline CdTe films were coated on glass and silicon substrates using the vacuum evaporation (PVD) technique, with annealing temperatures of 25, 100, 150, and 200 °C. This study aims to create a simple photoelectric cell using the effective light-absorbing layer CdTe as a thin film and Si as an n-type semiconductor. Additionally, it investigates the properties of CdTe thin films annealed at various temperatures. The following equipment was used: XRD, UV-visible spectrophotometer, SEM, and AFM. Moreover, the electrical characteristics of the fully designed devices were tested using I-V measurements and the Hall effect. Thin-film photovoltaics could become the primary source of global electricity. The CdTe thin films were coated using thermal evaporation. The best efficiency was 0.99% for the CdTe/Si structure with Voc = 5.0 x 10-1 V, Jsc = 51.0 x 10-2 mA/cm2, FF = 0.39, at 25 °C, and the efficiency decreased with increasing temperature. It has been found that annealing temperatures have an impact on the size of crystallites, the values of energy gaps, and the electrical properties of CdTe thin films.

Theoretical Study of the Phonon and Electrical Conductivity Properties of Pure and Sr-Doped LaMnO3 Thin Films.

The film thickness, temperature, substrate and doping dependence of the phonon energy ω and damping γ, as well as the electrical conductivity, of pure and Sr-doped LaMnO3 thin films near the phase transition temperature TN are investigated using a microscopic model and the Green's function technique. Due to the strong spin-phonon interaction, there appears a kink at TN in the temperature dependence of ω(T) and γ(T). The softening and hardening of the ω = 495 cm-1 (A1g) and ω = 614 cm-1 (B2g) modes is explained by the different sign of the anharmonic spin-phonon interaction constant R. The damping increases with T for both cases because it is proportional to R2. ω decreases whereas γ increases with an increasing Sr concentration. This is due to the strain caused by the difference between the ionic radii of the La and Sr ions. The film thickness dependence is also considered. ω and γ increase strongly with the decreasing film thickness. The electrical conductivity is enhanced after the doping of the LMO thin films with Sr, which could be used for energy storage applications. The observed results are in good qualitative agreement with the experimental data.

Effects of thermal treatment on the electrical behavior of titanium dioxide thin-films

AbstractElectrochemical biosensors made of titanium dioxide have generated significant interest due to their high sensitivity and selectivity for the detection of a variety of diseases. This study focuses on the impact of thermal treatment in an oxygen environment on the electrical properties of titanium dioxide thin films deposited on silicon substrates using pulsed laser deposition; the films were subjected to temperatures of $$\varvec{100\,\,^{\circ }C}$$ 100 ∘ C , $$\varvec{400\,\,^{\circ }C}$$ 400 ∘ C , and $$\varvec{600\,\,^{\circ }C}$$ 600 ∘ C . The primary objective was to explore how thermal processing influences the electrical characteristics of the thin films, with the goal of enhancing their capacitance and thereby improving the performance of sensors developed by functionalizing these films; X-ray photoelectron spectroscopy revealed the presence of Ti$$^{4+}$$ 4 + , Ti$$^{3+}$$ 3 + and TiO$$_x$$ x species in the untreated thin film and in the heat-treated films, with an increase in TiO$$_x$$ x species observed after oxygen heat treatment. Atomic force microscopy demonstrated a decrease in the surface homogeneity of the films at elevated treatment temperatures, which corresponded to a reduction in capacitive behavior; this was further corroborated by Nyquist plots derived from electrochemical capacitance spectroscopy (ECS). The study found that the electrochemical capacitance at lower frequencies decreased significantly from $$\varvec{1.02\,\, \mu Fcm^{-2}}$$ 1.02 μ F c m - 2 to $$\varvec{0.25\,\, \mu Fcm^{-2}}$$ 0.25 μ F c m - 2 when the treatment temperature was increased to $$\varvec{600\,\,^{\circ }C}$$ 600 ∘ C

Effect of substrate temperature on growth mechanism and properties of PEALD-MgO dielectric films for amorphous-IGZO TFTs

Magnesium oxide (MgO) films have been prepared by plasma enhanced atomic layer deposition with bis(cyclopentadienyl)magnesium precursor and oxygen plasma reactant at substrate temperature between 150 °C and 450 °C. The structural, morphological, optical, and chemical properties of the prepared MgO films were studied by spectroscopic ellipsometer, grazing incidence X-ray diffraction (GIXRD), field emission scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy (XPS). The electrical property of MgO film was obtained by performing capacitance-voltage measurement on the Al/MgO/Si structures. The experiment result shows that growth rate of MgO film decreases with the deposition temperature increased. GIXRD analysis presented that MgO films are cubic with predominantly (220) crystal orientation. XPS analysis shows that ratio of Mg/O is highest in MgO film prepared at 350 °C. To illustrate the possible applications of MgO film as a gate dielectric in thin film transistor (TFT), indium‑gallium‑zinc oxide (IGZO) was used as channel layer. The optimized IGZO/MgO TFT showed an electron mobility of 1.63 cm2/Vs, an on/off current ratio of 106, and a subthreshold swing of 0.50 V/decade at a low operation voltage of −0.11 V.

Fabrication and Characterization of Nanostructured Tin doped Indium Oxide Coatings by the Instrument of Spray Pyrolysis

Nanostructured indium tin oxide (ITO) coating is one of the transparent conductive oxides (TCO) materials utilized as a transparent electrode. Due to its high demand in various applications like liquid crystal displays, touch screens, light emitting devices, and solar cells, ITO coatings have garnered significant research attention, owing to their excellent properties of high visible light transmittance and low resistance. Nanostructured coating of tin -doped Indium Oxide (ITO) was fabricated on glass slides utilizing the instrument of chemical spray pyrolysis (CSP), with varying levels of Sn-doping at 0, 3, 6, and 9 wt%. The effect of tin content on the many physical characteristics of the resulting coatings has been examined. The analysis of x-ray diffraction (XRD) displayed the characteristic orientations. The coatings have a polycrystalline cubic lattice structure along (400) as the preferred growth direction. Morphological measurements indicate that the samples possess a highly uniform surface and the grain size for the ITO samples is 100 nm displaying a nanostructure for all samples. The optical transmittance was measured over 75% for coating with tin content equal to 0wt%, while the transmittance of the Sn-doped films can range from 78% to 84% at 700 nm and the values of the direct bandgap were measured as 3.6, 3.65, 3.675, and 3.7eV for Sn doping 0, 3, 6, and 9 wt% respectively. In the visible area, the nanostructured ITO coatings exhibit elevated values of transmittance which makes them suitable for various optoelectronic applications such as window materials in solar cells. The results indicate a desirable reduction in the electrical resistivity with rising the number of carriers per unit volume and mobility with increasing tin content in the samples. The minimum electrical resistivity and maximum carrier concentration were achieved for ITO coating with tin content equal to 9wt%. The incorporation of Sn dopant significantly changes the overall electrical properties of indium oxide films, this is favorable for transparent conducting oxide.

An investigation of structural, electrical and optical properties of metal free-Zinc Oxide Thin Films Using Spray Pyrolysis Sol-Gel Techniques

An investigation of structural, electrical and optical properties of metal free-Zinc Oxide Thin Films Using Spray Pyrolysis Sol-Gel Techniques

The inner workings of sp2 clusters in nitrogen-incorporated tetrahedral amorphous carbon thin films according to optical analyses

The conduction mechanism in nitrogen-incorporated tetrahedral amorphous carbon (ta-C: N) thin films is mainly attributed to the conjugation in sp2 clusters. Here, ta-C:N thin films (about 100 nm) were deposited by laser controlled pulsed cathodic vacuum arc (Laser-Arc) at different nitrogen gas flow rates to investigate the electrical properties of such films. Mechanical and structural properties indicate an increase in sp2 fraction with a rise in nitrogen incorporation into the deposited films. However, after an initial decrease in electrical resistivity, it plateaus at higher flow rates while the sp2 content is still rising. Hence, to gain better understanding of the electronic properties, the dielectric constants ε1 and ε2 were obtained from the optical constants [n] and [k], which were numerically determined from reflectance [R] and transmittance [T] measurements in the wavelength range from 190 to 2500 nm (0.5 to 6.5 eV). The dielectric constant ε1 was used to calculate the dielectric volume of the atom, which is interpreted as a measure of the conjugated π electron system. Furthermore, modeling of the dielectric constants yielded the number of conjugated electrons per atom. Through the dielectric volume and number of conjugated electrons, it was discovered that the electrical conductivity does not only depend on the sp2 content and cluster size, but on how many electrons are conjugated and how much space these electrons occupy. The ta-C:N samples with the highest electrical conductivity, were either characterized by the largest occupied volume or the highest number of conjugated electrons.

Gamma-irradiated stibnite thin films set a remarkable benchmark performance for photoelectrochemical water splitting.

The study sets out to show the positive impact of sulfur vacancy engineering on the structural, morphological, optical, electrical, and photoelectrochemical (PEC) properties of Sb2S3 films synthesized using the spin coating technique. The produced films were exposed to γ-irradiation with different doses from 0 to 20 kGy. We have demonstrated the formation of sulfur vacancies and loss of oxygen content in the irradiated samples. XRD measurements revealed that all films exhibit a polycrystalline structure, and the crystallite size increases with the rising radiation dose, reaching the highest value of 87.4 nm measured for the Sb2S3 film irradiated with 15 kGy. The surface roughness of the irradiated samples increases with increasing γ-irradiation dose. The increase in surface roughness not only raises the active sites but enhances the conductivity of the Sb2S3 material as well. The wettability properties of the irradiated films were affected by γ-irradiation doses and the sample irradiated with 15 kGy exhibited the lowest hydrophobicity compared to others. The Hall measurements reveal that irradiated samples exhibit p-type semiconductor behavior. The optical band gap decreased progressively from 1.78 eV to 1.60 eV up to the irradiation dose of 15 kGy and slightly increased thereafter. The irradiated sample with 15 kGy showed a maximum photocurrent density of ca. 1.62 mA cm-2 at 0 V vs. reverse hydrogen electrode (RHE) under AM 1.5 G illumination with applied bias photon-to-current efficiency (ABPE) of 0.82% at 0.47 V vs. RHE, suggesting superior PEC water splitting performance compared to other samples. At 0 V vs. RHE and 648 nm, the incident photon current efficiency (IPCE) and absorbed photon current efficiency (APCE) of the photocathode irradiated with 15 kGy are significantly higher than those of the other photocathodes with values of 9.35% and 14.47%, respectively. Finally, Mott-Schottky measurement was also performed on all photocathodes to estimate their acceptor density and flat band potential.

Physical investigations: structural, morphological, optical and electrical properties of CoFeS2 thin films prepared using a chemical spray technique

Physical investigations: structural, morphological, optical and electrical properties of CoFeS2 thin films prepared using a chemical spray technique

Influence of Different Polymorphs on the Electrical and Mechanical Properties of F4TCNQ-Doped Regioregular P3BT Films

Influence of Different Polymorphs on the Electrical and Mechanical Properties of F4TCNQ-Doped Regioregular P3BT Films

Variation of electrical properties with temperature for polyethylene oxide doped with 0.1 wt. % iodine

The electrical properties of thin films made of polyethylene oxide (PEO) dispersed with dopants fixed amount of iodine (0.1 wt. %) were studied using the AC impedance technique. The films were prepared by electrically casting method. In this present work, the variation of AC electrical conductivity with temperatures ranging from 30 oC to 55 oC at a frequency of 200 kHz for (PEO) film doped with 0.1wt. % iodine and undoped (PEO) film were studied. Physical quantities and parameters such as AC conductivity, impedance, dielectric constant, and dielectric loss, were determined. The observed values of the impedance (Z), dielectric constant ('), dielectric loss ("), and AC-conductivity (σAC) showed temperature dependence. It was found that the dielectric constant and the dielectric loss of the prepared thin films increased with doped (0.1wt. %) iodine complexes and also increased with the increase of temperature according to the polarization processes.

Study the Effect of Ni Doping on Structural, Optical and Electrical Properties of Ni1-xAgxO Thin Films Deposited by Spray Pyrolysis Technique

Study the Effect of Ni Doping on Structural, Optical and Electrical Properties of Ni1-xAgxO Thin Films Deposited by Spray Pyrolysis Technique