Radio-frequency Sputtering Technique Research Articles

Optical Studies of Silver Oxide Deposited Thin Films Using the RF Sputtering Technique

Background/Objectives: Silver Oxide is an efficient material because it is used in batteries. Apart from this, it is a moderate oxidizing agent in a variety of processes including the oxidation of aldehydes to carboxylic acids. The objective of the study is to synthesize silver oxide films by RF sputtering technique so that synthesized films can be inserted in the spectrophotometer for optical study. Methods: Silver Oxide films were deposited on Fluorine-doped Tin Oxide (FTO) glass using Radio Frequency (RF) sputtering method and annealed at 200 °C, for two hours, and then it was used in DK2 Ratio recording Spectrophotometer to analyze absorption and transmission data. Findings: The thickness of the films was measured using a non-contact optical Profilometer, in the range of (42– 660) nm. The films were subsequently exposed to optical characterization, revealing exceptionally low transmittance and high absorbance. The band gap is estimated to be 2.2 eV. The X-ray diffraction (XRD) studies reveal that the material is crystalline and Miller indices have also been determined. The morphology and topography of the thin films were analyzed using Field Emission Scanning Electron Microscope (FESEM) and the chemical composition was estimated using EDS. Novelty: The present work reveals that the optical properties are highly dependent on the thickness and the material distribution. The direct band gap energy is evaluated from the absorption spectrum which comes out to be 2.2 eV. The XRD spectra synthesized Silver Oxide films are crystalline in nature. Keywords: Silver Oxide, Band gap, XRD, FESEM

Design and fabrication of micro carbon dioxide sensor based on TiO2 thin film

Abstract A micro-electro-mechanical systems (MEMS)-based micro carbon dioxide sensor is fabricated using conventional photolithography, electron beam evaporation, and radio frequency sputtering techniques. The sensor consists of a titanium dioxide sensing layer, interdigital electrodes (IDEs), a platinum resistance temperature detector (RTD), and an aluminium oxide substrate. Given a working temperature greater than 300°C, the resistance of the titanium dioxide sensing layer increases linearly with an increasing carbon dioxide concentration. Fluctuations in the working temperature are detected by the RTD and compensated using a proportional-integral-derivative (PID) feedback control system implemented in LabVIEW. The temperature detection results reveal that the RTD has a sensitivity of 1.3 mV/°C. The sensor is calibrated using a standard carbon dioxide detector and is used to perform carbon dioxide sensing at working temperatures of 300°C, 350°C, and 400°C, respectively. It is shown that the highest sensitivity of (0.179 MΩ/ppm) and fastest response time (15 seconds) are attained at a working temperature of 350°C.

High gain NiO/ZnO heterojunction photodiodes operated in Deep-ultraviolet region

Epitaxially matched (0001) Al2O3 single substrates are utilized to design p-n heterojunctions (p-NiO/n-ZnO) as they offer low defect density for device fabrication due to small lattice mismatches. Using the radio frequency sputtering technique, the NiO/ZnO thin film-based heterojunction has been fabricated by varying the n-type film's (ZnO) thickness for ultra-violet (UV) photodiode application. It has been investigated how different ZnO film thicknesses affect junction parameters and photoresponse properties. The high photosensitivity (∼ 104), enhanced current gain (∼ 105) and fast response obtained at very low UV intensity (0.62μW/cm2) at 300 nm wavelength are attributed to the internal gain mechanism (recombination tunnelling and space-charge limited current conduction with the remarkable effect of the presence of excess free oxygen) in these devices. The prepared heterojunction photodiode with high speed and deep-UV sensitivity can be a potential solution for visible blind UV detection.

A comparative study of ZnO, AZO, TiO2, Sb2O3, and SnO2 nanomaterials coated SPR based fiber optic refractive index sensors for chemical sensing application

This paper presents a comprehensive investigation of Surface Plasmon Resonance (SPR) based fiber optic sensors tailored for precise detection of refractive index (RI) variations in acetone and ethanol solutions. The sensor probe design incorporates a nanostructure comprising a metal layer (Ag, Al, or Cu) and a metal oxide sensing layer (ZnO, AZO, TiO2, Sb2O3, SnO2) over the fiber core. Employing the Transfer Matrix Method (TMM), optimal layer thicknesses were determined, with a combination of 50 nm Ag and 20 nm metal oxide demonstrating maximum sensitivities. The sensor probes were fabricated using the Radio Frequency (RF) sputtering technique, and their uniformity, elemental composition, and optical properties were assessed through Field Emission Scanning Electron Microscope (FESEM) and ellipsometer analyses.The sensor response of the probes is 12 %, 7.1 %, 10.8 %, 6.08 %, and 11.34 % for acetone and 11.9 %, 9.2 %, 12 %, 7.89 %, and 12.48 % for ethanol. Sensitivities ranged from 2.7 nm/v% to 2.84 nm/v% for acetone and 1.90 nm/v% to 3.02 nm/v% for ethanol, with the SnO2-coated probe exhibiting the highest sensitivity. Further sensitivity enhancement was achieved by introducing a bimetal layer (50 nm Ag/5 nm Sb/20 nm SnO2), resulting in a 15 % increase for ethanol compared to the Ag/SnO2-based SPR probe.

Fabrication of microfluidic pH sensing chip based on sputtered Sb2O3/Sb thin film working electrode and AgIO3/Ag thin film reference electrode for detection of A549 cells

In this study, we present the fabrication and characterization of a microfluidic pH sensing chip designed to detect human lung cancer (A549) cells. The chip utilizes a Sb2O3/Sb thin film as the working electrode and an AgIO3/Ag thin film as the reference electrode, both deposited using the radio frequency (RF) sputtering technique. The PDMS microfluidic channel was prepared using a 3D-printed mold, followed by curing of PDMS within the mold. The fabricated sensing chip demonstrated excellent linear response (R2 ∼ 0.99) and appreciable Nernstian sensitivity (average = -57.02 ± 1.23 mV/pH, n = 4) in a wide pH range of 1.68–10.01. It exhibited good stability over a 48-hour duration with acceptable drift voltage and negligible temperature impact on the sensing performance. Further, in-vitro pH testing of human lung cancer (A549) cells was performed to investigate the real-time pH measurement ability of the developed microfluidic pH sensing chip.

Characterization of NiOAg thin film applicated as photocatalyst for degradation of methylene blue dye waste in Yogyakarta textile factory

Thin films of NiOAg were grown onto glass substrates by radio frequency (RF) sputtering technique at 13.56 MHz RF with variation in oxygen pressure. The research was conducted on preparation and characterization of NiOAg thin films, applicated as a photocatalyst for the degradation of methylene blue. X-ray diffraction analysis showed stronger intensity (111) and (200) planes at peak 2θ of 37.66° and 43.23°. Energy dispersive x-ray analysis showed the following composition: Ni = 40.45%, Ag = 13.01%, and O = 46.53%. Based on UV–vis, it was found that the bandgap energy was 2.8, 3.1, and 3.2 eV for oxygen pressures of 0.05, 0.1, and 0.15 × 10−2 mbar, respectively. From the experiment on the degradation of methylene blue, which was taken from textile factory dye waste in Yogyakarta/Indonesia, the best value of degradation was obtained as 91.96%.

The effect of Ar:O2 gas ratios on the structural and optical properties of RF sputter-deposited La2O3-doped ZnO thin films

Due to their unique scintillation, phosphorescence, magnetic, and catalytic properties, rare earth oxide compounds have recently become one of the most in-demand materials used in different ways. The current study investigated the impact of Ar:O2 gas flow variation on the deposition of La2O3-doped zinc oxide thin films (TFs) on silicon dioxide (SiO2) substrates using the radio frequency sputtering technique. FE-SEM analysis has shown a smooth surface topology and purity of La2O3-doped ZnO TFs. X-ray diffraction analysis exhibited a single-phase hexagonal wurtzite-type structure in TFs. A UV–Vis–IR spectrophotometer examined the optical characteristics of ZnO and La2O3-doped ZnO TFs in 300–800 nm wavelength range. The bandgap of La2O3 doped ZnO TFs changed from 2.9 to 3.1 eV as argon and oxygen concentrations in (Ar:O2) gas flow changed. A variation in optical constants such as dielectric constants, refractive index, and extinction coefficient was observed when ZnO and La2O3-doped ZnO TFs were exposed to variable (Ar:O2) gas flow ratios. The photoluminescence analysis of ZnO and La2O3-doped ZnO TFs was performed at an excitation wavelength of 330 nm. Atomic force microscopy further revealed that La2O3 doping resulted in smoother surfaces and smaller grain sizes. This comprehensive study provides valuable insights into the relationship between doping, gas composition, and the optical and structural properties of ZnO TFs. The obtained results on the optimal flow rate of argon gas provide valuable insights for determining the appropriate deposition conditions of La2O3-doped ZnO TFs, specifically for their application in solar thermal systems.

Effect of RF-sputtering temperature of ITO electrodes on the resistive switching behaviour of ITO/RbPbI3/Cu devices

In this work, we deposit Indium doped Tin Oxide (ITO) on a glass substrate using the Radio-Frequency Sputtering technique at different temperatures and studied its structural and optical properties. Various structural, optical, and morphological studies are conducted on the ITO substrates. In addition, we have used these ITO films as conducting electrodes in MIM (metal-insulator-metal) type structures for resistive memory application. A resistive switching memory device based on RbPbI3 with sputtered ITO films as the bottom electrode is fabricated and studied for its electrical performance. It has been found that the device showed the write-once-read-many (WORM) nature at a sputtering temperature of 300 °C with a good OFF/ON ratio. The devices with ITO film sputtered a temperature below 300 °C do not show any switching behavior due to lower conductivity and improper surface morphology.

Antimony doped tin oxide MOS sensors for hydrogen detection at low concentrations

In this study, Antimony (Sb) doped tin oxide (SnO2) thin films (ATO) were synthesized using the RF (radio frequency) sputtering technique with varying antimony concentrations (0, 3, 5, 7 wt%) and substrate temperatures of room temperature, 150 ℃, and 300 ℃. It was discovered that these thin films were tetragonal crystal structures with good crystallinity and grew preferentially along the (101) planes at the substrate temperature of 300 ℃. It was found that the 5 wt% doped film prepared at 300 ℃ substrate temperature exhibited superior gas-sensing properties under all tested conditions, and the 7 wt% doped sample showed properties that deviated from the trend observed up to 5 wt%. It was observed that the morphology of the film has a spongy spherical granular structure with a mesoporous surface. The presence of Sn, Sb5+/Sb3+, and oxygen was confirmed by XPS spectra analysis in the thin films. The n-type electrical conductivity was attained by combining an oxygen vacancy and antimony ions in the tin oxide lattice interstitial. Consequently, the inclusion of antimony increased conductivity up to 5 wt% was noticed. Doping makes remarkable changes in surface roughness (14–163.48 nm), which is attributed to the surface wettability. The film turns nearly hydrophilic when the doping concentration increases (59°). According to studies into a potential gas-sensing mechanism, the addition of Sb dopants, mesoporous structures, and high specific surface area was thought to be the reason for the improved gas-sensing response. Without a doubt, the current work may offer the best method to enhance H2 gas response in particularly environmentally sensitive applications.

Influence of tungsten oxide concentration on structural, morphological, compositional, linear and non-linear optical properties, and vibrational properties on NiO:WO3 thin films

Mixed nickel-tungsten oxide, NiO:WO3 (90:10, 85:15) thin films with different tungsten oxide (WO3) concentrations of 10 and 15% were deposited using the radio frequency (RF) sputtering technique. An X-ray diffraction analysis reported the amorphous nature of the films. A SEM study showed smooth morphology. EDAX confirms the compositional purity, in which the nickel content decreases, while the tungsten and oxygen content increase with an increased WO3 concentration. The average transmittance of the NiO:WO3 (90:10, 85:15) films decreases from 79 to 75% as a consequence of increased thickness. The Urbach energy (Eu) enhances because of increased defects (localized states) inside the films induced by tungsten oxide addition. The energy bandgap decreases from 2.66 to 2.48 eV due to the formation of new localized energy states inside the band gap (Eg). The refractive index (n) acquired from different proposed models for the entire UV–Vis–NIR region has increased with increasing WO3 concentration, implying the escalation in densification (or packing density) of prepared films. The optical parameters like n, k, ε1, ε2, electronic polarizability (αp), optical conductivity (σop), electric conductivity (σe), volume and the surface energy loss function (VELF AND SELF) vary with WO3 concentration. The dispersion energy parameters (Eo, Ed), resulting from the Wemple and Didomenico (WD) model, decreases. The optical non-linear susceptibility, χ(3), decreased with increasing WO3 concentration. The photoluminescence (PL) emissions were perceived at 368 nm and 423 nm, assignable to 3 d8 Ni2+ ions transitions. Micro-Raman detected peaks at 570 cm−1 and 1100 cm−1 ascribing Ni–O bond vibrations, whereas the peak spotted at 870 cm−1 is ascribed to a W–O bond vibration. The deposited films are good enough for electrochromic and optoelectronic device fabrications.

Dissolution of Mg(OH)2 by swift heavy ion irradiation in CoFe2O4/MgO/ZnFe2O4 multilayer thin films

In-situ system for metallic multilayer thin films used for magnetic tunnel junction (MTJ) required a multi-target system to avoid the formation of impurities which make these devices very costly. In this work, the study was performed to resolve this issue by using a single target system for multilayer formation and impurity phases were dissolved by swift heavy ion (SHI) irradiation. A pristine MgO/Si(100) and CoFe2O4/MgO/ZnFe2O4/Si(100) (CFMZF) multilayer thin film were prepared via radio frequency (RF) sputtering technique. These structures were irradiated by 75 MeV oxygen-ion (O-ion) fluence (5x1011, 1x1012, and 5x1012 ions/cm2) and 200 MeV silver-ion (Ag-ion) fluence (1x1012 ions/cm2) for the investigation of structural changes. The high-resolution X-ray diffraction (HRXRD) reveals that MgO and CFMZF thin films have impurity peaks, dissolved via O-ion and Ag-ion irradiation. Further HRXRD analysis confirmed that Ag-ion irradiation dissolves more peaks leaving one small intensity peak of (400) corresponding to MgO. The multilayer stack of CFMZF irradiated via Ag-ion shows that Mg(OH)2 phase were completely dissolved and appears only (311) less intense peak corresponding to the ferrite structure. The findings are also corroborated by cross-sectional field emission scanning electron microscopy of CFMZF multilayer thin film showing damaged layers with Ag-ion irradiation. Therefore, the SHI irradiation technique can be used to dissolve the impurity peaks and improve the interface of the multilayer stacks.

Impact of top metal electrodes on current conduction in WO3 thin films

Abstract Using radio-frequency (rf) sputtering technique tungsten oxide (WO3) thin films (∼150 nm) were deposited in a gas mixture of Ar and O2 at 10 mTorr pressure on indium tin oxide (ITO) and corning glass substrates. The films were annealed at 400 °C. Structural and optical properties of films were studied. Metal–insulator–metal (MIM) structure was made by depositing metal electrode (Ag, Al, Au) on the prepared WO3 thin films (on ITO substrate) using thermal evaporation technique. Electrical properties of the MIM structure were studied by plotting current versus voltage (I–V) curves for Ag, Al and Au metal electrodes. Current conduction mechanism in WO3 film was determined by plotting and fitting I–V data in different equations of current mechanisms.

UV Sensor Based on Surface Acoustic Waves in ZnO/Fused Silica.

Zinc oxide (ZnO) thin films have been grown by radio frequency sputtering technique on fused silica substrates. Optical and morphological characteristics of as-grown ZnO samples were measured by various techniques; an X-ray diffraction spectrum showed that the films exhibited hexagonal wurtzite structure and were c-axis-oriented normal to the substrate surface. Scanning electron microscopy images showed the dense columnar structure of the ZnO layers, and light absorption measurements allowed us to estimate the penetration depth of the optical radiation in the 200 to 480 nm wavelength range and the ZnO band-gap. ZnO layers were used as a basic material for surface acoustic wave (SAW) delay lines consisting of two Al interdigitated transducers (IDTs) photolithographically implemented on the surface of the piezoelectric layer. The Rayleigh wave propagation characteristics were tested in darkness and under incident UV light illumination from the top surface of the ZnO layer and from the fused silica/ZnO interface. The sensor response, i.e., the wave velocity shift due to the acoustoelectric interaction between the photogenerated charge carriers and the electric potential associated with the acoustic wave, was measured for different UV power densities. The reversibility and repeatability of the sensor responses were assessed. The time response of the UV sensor showed a rise time and a recovery time of about 10 and 13 s, respectively, and a sensitivity of about 318 and 341 ppm/(mW/cm2) for top and bottom illumination, respectively. The ZnO/fused silica-based SAW UV sensors can be interrogated across the fused silica substrate thanks to its optical transparency in the UV range. The backlighting interrogation can find applications in harsh environments, as it prevents the sensing photoconductive layer from aggressive environmental effects or from any damage caused by cleaning the surface from dust which could deteriorate the sensor's performance. Moreover, since the SAW sensors, by their operating principle, are suitable for wireless reading via radio signals, the ZnO/fused-silica-based sensors have the potential to be the first choice for UV sensing in harsh environments.

Divulging the Potential of Sodium Carbide Thin Film for Semiconductor Applications

The work reported in this article is an attempt to introduce the least explored sodium carbide as a thin film and to explore its semiconducting behavior. The sodium carbide thin film deposited by the radio frequency sputtering technique is subjected to morphology, structure, and spectroscopic characterizations. The floral petal‐like morphology, understood from the field‐emission scanning electron microscopy and atomic force microscopy images, helps in enhancing interaction with the radiation that is revealed through the UV–visible absorption spectrum. X‐ray diffraction, photoelectron and Raman spectroscopic analyses confirm that the film is sodium carbide. The optical emission behavior of the sodium carbide thin film in the blue region is unveiled through the photoluminescence spectrum, power spectrum, color purity, and chromaticity diagram. Employing the refractive index and extinction coefficient values from the specular reflectance data, optical and electrical conductivities, nonlinear refractive index, linear and nonlinear optical susceptibility, dissipation factor, and surface and volume energy loss functions and their wavelength dependence due to interfacial polarization are investigated. The transfer matrix method is used to understand the spatial variation of the induced electric field and optical current density.

Impact of annealing on structural and optical properties of ZnO thin films

This paper analyzes the effect of annealing on morphological, structural and optical properties of Zinc Oxide (ZnO) thin films and their applications in optical sensing. ZnO thin films were deposited using radio frequency (RF) sputtering technique followed by annealing in presence of nitrogen environment at 100 °C, 200 °C and 300 °C. The effect of the annealing on surface and structural properties were studied through SEM, AFM, XRD, Raman and PL. Increment of the annealing temperature improves the texture coefficient of the film in (101) plane. Further optical sensing was performed on annealed ZnO thin films at room temperature. The results confirm that the annealing temperature of the thin films is related to crystalline structure and showed the highest optical response. The optimized annealed sample offers photo to dark current ratio (PDCR) in the order of 2.8 × 104. The annealed devices at 200 °C and 300 °C showed 102 times improved PDCR compared to devices annealed at 100 °C. This optimized sample showed improved results for UV range optical applications.

Sensor-on-Microtips: Design and Development of Hydrothermally Grown ZnO on Micropipette Tips as a Modified Working Electrode for Detection of Glucose.

Miniaturization of electrochemical components has become less common in the last decade, with the focus predominantly being the design and development of state-of-the-art microelectrodes for achieving small volume analysis of samples. However, such microelectrodes involve cumbersome processing procedures to convert the base material for the required application. A potential paradigm shift in such miniaturization could be achieved by using cheaper alternatives such as plastics to build electrochemical components, such as micropipette tips made of polypropylene, which are commercially available at ease. Hence, this work presents the design of an electrochemical working electrode based upon a micropipette tip, involving minimal processing procedures. Furthermore, such a working electrode was realized by sputtering silver onto a bare micropipette tip using a radio-frequency sputtering technique, to obtain electrical contacts on the tip, followed by hydrothermal growth of ZnO, which acted as the active electrode material. The ZnO nanostructures grown on the micropipette tip were characterized for their morphology and surface properties using a scanning electron microscope (SEM), laser microscope, Raman spectrometer, and X-ray photoelectron spectrometer (XPS). The developed micropipette tip-based electrode was then used as the working electrode in a three-electrode system, wherein its electrochemical stability and properties were analyzed using cyclic voltammetry (CV). Furthermore, the above system was used to detect glucose concentrations of 10-200 µM, to evaluate its sensing properties using amperometry. The developed working electrode exhibited a sensitivity of 69.02 µA/µM cm-2 and limit of detection of 67.5 µM, indicating the potential for using such modified micropipette tips as low-cost miniaturized sensors to detect various bio-analytes in sample solutions.

Silica Nanospheres Coated Silver Islands as an Effective Opto-Plasmonic SERS Active Platform for Rapid and Sensitive Detection of Prostate Cancer Biomarkers.

The in vitro diagnostics of cancer are not represented well yet, but the need for early-stage detection is undeniable. In recent decades, surface-enhanced Raman spectroscopy (SERS) has emerged as an efficient, adaptable, and unique technique for the detection of cancer molecules in their early stages. Herein, we demonstrate an opto-plasmonic hybrid structure for sensitive detection of the prostate cancer biomarker sarcosine using silica nanospheres coated silver nano-islands as a facile and efficient SERS active substrate. The SERS active platform has been developed via thin (5-15 nm) deposition of silver islands using a simple and cost-effective Radio Frequency (RF) sputtering technique followed by the synthesis and decoration of silica nanospheres (~500 nm) synthesized via Stober's method. It is anticipated that the coupling of Whispering Gallery Modes and photonic nano-jets in SiO2 nanospheres induce Localized Surface Plasmon Resonance (LSPR) in Ag nano-islands, which is responsible for the SERS enhancement. The as-fabricated SERS active platform shows a linear response in the physiological range (10 nM to 100 μM) and an extremely low limit of detection (LOD) of 1.76 nM with a correlation coefficient of 0.98 and enhancement factor ~2 × 107. The findings suggest that our fabricated SERS platform could be potentially used for the rapid detection of bio-chemical traces with high sensitivity.

Impact of deposition temperature on crystalline quality, oxygen vacancy, defect modulations and hetero-interfacial properties of RF sputtered deposited Ga2O3 thin films on Si substrate

In the current work, thin film (∼55 nm) of n-type Ga2O3 (n-Ga2O3) is deposited on silicon (p-Si) substrate by using radio-frequency (RF) sputtering technique with systematic substrate temperature variations (room temperature to 700 °C). The structural, optical properties and chemical states of elements of the deposited films are observed to depend significantly on the deposition temperatures. The chemical composition and oxidation states, optical properties, defect states and structural quality of the deposited films are investigated in detail by employing x-ray photoelectron spectroscopy, energy dispersive x-ray, spectroscopic ellipsometry, Raman, photoluminescence and atomic force microscopy images. X-ray diffraction result reveals a polycrystalline nature of monoclinic β-phase of Ga2O3 with (403) dominant plane. The work functions are calculated from the ultraviolet photo-electron spectroscopy for all the deposited films and Ga2O3/Si heterojunction properties are investigated by using current–voltage (I–V) and capacitance–voltage (C–V) measurements. Among all the fabricated heterojunctions, 600 °C deposited Ga2O3 film exhibits superior performance in terms of energy bandgap, work function, refractive index, barrier height, rectification ratio and effective carrier concentrations. The current transport mechanism is analysed using the appropriate energy band diagram of Ga2O3 and Si. Therefore, the study suggests that 600 °C deposition temperatures is the optimum temperature for developing a high quality Ga2O3 thin film on Si by using RF sputtering technique and corresponding Ga2O3 thin film/Si heterojunction can be a potential candidate for developing several electronic and optoelectronic devices.

Enhanced Visible Light Transmittance and Phase Transition in ZnO/VO2 /AL2O3 Bilayer Thin Film for Energy Efficient Smart Windows.

To ameliorate the limitation of low visible light transmittance of smart window, single phase Vanadium dioxide (VO2) and bilayer of Zinc oxide ZnO/VO2 on Al2O3 substrate were fabricated using the Radio frequency (RF) sputtering technique. These films were deposited at different temperature ranges starting from 28 degrees Celsius which goes up to 90 degrees Celsius. Structural Phase transition was witnessed from monoclinic to rutile phase after a critical temperature (Tc) of 68 degrees Celsius. Structural characterisation was done using the X-rays diffraction(XRD) analysis technique at grazing incidence mode by using monochromatic X – rays (λ = 0.06926 nm). Further, the morphology of the surface structures was studied by using field emission scanning electron microscopy (FESEM). The visible light transmittance change was studied using the Ultra Violet (UV) – Vis spectroscopy in transmittance mode at room temperature. This increased transmittance of the bilayer deposited can be a potential way out to have more efficient smart windows.

Microstructural properties of SiC thin film deposited by RF sputtering technique and its role on the barrier parameters of n-InP/Pd and n-GaP/Pd junctions as an interlayer

In this study, the microstructural properties of Silicon carbide (SiC) thin film deposited by radio frequency (RF) sputtering technique and the effects of SiC as an interlayer on the barrier parameters of n-GaP/Pd and n-InP/Pd junctions were examined comparatively. Firstly, Al/n-GaP/Pd and In/n-InP/Pd diode structures were fabricated and their barrier parameters were analyzed using Rhoderick, Norde, Cibils and Chattopadhyay methods at room temperature. Then, SiC thin films, which were deposited on Al/n-GaP and In/n-InP semiconductors, respectively, with the help of SiC target using RF sputtering technique, were inserted into the In/n-InP/Pd and Al/n-GaP/Pd junctions as an interlayer, and In/n-InP/SiC/Pd and Al/n-GaP/SiC/Pd structures were produced. Microstructures of SiC thin films were evaluated with the help of x-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray analysis (EDX) measurements. In order to interpret the barrier properties of Al/n-GaP/SiC/Pd and In/n-InP/SiC/Pd structures in detail and to compare them with those without interlayers, current-voltage (I–V) measurements were measured at room temperature under dark conditions and the junction parameters were recalculated with the help of the methods mentioned above. It has been determined that SiC interlayers play important roles on the barrier properties of Al/n-GaP/Pd and In/n-InP/Pd diode structures.