DC Magnetron Sputtering Research Articles

Study on the process of hydrogen-doped indium oxide for silicon heterojunction solar cell mass production

In this work, we conducted a comparative study on water vapor (H2O) process and hydrogen gas (H2) process to prepare the IMO:H films based on industrialized DC magnetron sputtering system. To dynamically control the residual H2O pressure, we installed a set of polycold coil and kept it turned on during the sputtering process. The film characteristics of Hall mobility, carrier density, sheet resistance, and transparency was investigated. The results revealed that the silicon heterojunction (SHJ) solar cell with H2 process had a higher Hall mobility and greater transparency in the 400–600 nm wavelength range resulting in a lower contact resistivity and a slight increase current density compared to the H2O process. The median efficiency (Eff) achieved with the H2 process improved by 0.09% absolute to 25.43%, mainly because of the increased Jsc and FF. And the IMO:H films with H2 process had a large basal spacing with (400) and (222) crystal planes resulting in maintaining a more stable and reliable structure at temperatures below 200 °C. After the optimization of TCO layer process, we manufactured the industrial-grade SHJ cells with max efficiency (Eff), Voc, Jsc, and fill factor (FF) values as high as 26.27%, 753 mV, 41 mA/cm2, and 86%, respectively. The IMO:H films with H2 process can thus be considered more suitable for large-scale production.

Optimized Tribological Performance of Nitrogen-Doped Diamond-like Carbon Films on NBR: Influence of Bias Voltage of DC Magnetron Sputtering.

In this research, nitrogen-doped diamond-like carbon (N-DLC) coatings were deposited on Nitrile Butadiene Rubber (NBR) substrates using direct current magnetron sputtering (DC-MS) under varying bias voltages. This study aimed to explore environmentally friendly, low-wear, and non-lubricating seal coatings to enhance the durability of rubber sealing products, which predominantly operate under dynamic sliding conditions. By reducing the coefficient of friction (CoF), the friction and wear on rubber products can be significantly minimized, extending their lifespan. This investigation thoroughly examined the microstructure, mechanical properties, and tribological behavior of the N-DLC films. Among the coatings, the one produced at a bias voltage of -50 V demonstrated superior hardness, elastic modulus, and the lowest CoF in comparison to those prepared with 0, -100, and -200 bias voltages. This optimal combination of properties resulted in an exceptionally low wear rate of 10-9 for the film deposited at -50 V, indicating its outstanding wear resistance.

Effect of rapid thermal annealing on microstructure, mechanical and tribological properties of amorphous SiC hard coatings

Herein, a-SiC hard coatings were prepared by pulsed DC magnetron sputtering followed by rapid thermal annealing (RTA) at various temperatures. The influence of the RTA temperature on the coatings’ microstructure, mechanical and tribological properties was investigated. The results show that the surface morphology of a-SiC coatings almost unchanged and remains amorphous within 973 K annealing temperature. The content of sp3 first increases and then decreases with increasing annealing temperature, and reaches the maximum value at 773 K. The hardness (H) and elastic modulus (E) of the a-SiC coatings also increase firstly and then decrease due to the variation of sp3 content, while average friction coefficient decreases first and then increases. As the annealing temperature is 823 K, the maximal H, E of 25.02 GPa, 243.63 GPa are obtained. At 773 K annealing temperature, the minimum friction coefficient of 0.107 is realized, a-SiC coating exhibits higher H/E, H3/E2 and tribological properties.

Surface temperature of a 2 in. Ti target during DC magnetron sputtering

Recently, there has been increasing interest in the use of hot targets to enhance the sputter deposition of materials. However, the actual temperature of the target surface is normally not known. In this work, we directly measured the radial distribution of the surface temperature of a MAK 2 in. Ti water-cooled target using a type K thermocouple during the operation of the sputtering system. Principally, the measurements were made as a function of applied DC power and argon gas pressure. Given the importance of chemical reactions between the gas and the target during reactive sputtering, we have also measured the target temperature as a function of the nitrogen concentration in an argon-nitrogen gas mixture. A few of the reactively sputtered samples were analyzed by x-ray photoelectron spectroscopy.

Investigation of optical and electrical properties of TiO2, SiO2, and Ag single and multilayer thin films using spectroscopic ellipsometry and spectrophotometry methods: prepared by spin coating and DC magnetron sputtering

In this work, spectroscopic ellipsometry was used to study the optical and electrical properties of TiO2 and SiO2 thin films deposited by spin-coating at different coating rotation speeds and annealed at various temperatures. In addition, Ag thin films of different thicknesses were deposited by DC magnetron sputtering at ambient temperature. In this method, the optical band gap for TiO2 thin films is between 3.15–3.85 eV, and for SiO2 thin films, it is between 3.2–3.8 eV. The optical properties, including reflectance, transmittance, and absorbance, of TiO2, SiO2, and Ag thin films in the form of single and multilayer thin films in the wavelength range of 200–2500 nm, were investigated using an ultraviolet-visible-near infrared (UV–vis-NIR) dual-beam spectrophotometer. In the TiO2/Ag/SiO2 multilayer thin film, the rejection was 58.6% −73.6% in the NIR wavelength range (800–2500 nm), and a transmittance of 40%–45% was achieved in the visible light range (400–700 nm).

Effects of thickness ratio on phase structures, mechanical properties, and wear behaviors of CrN/ZrB2 bilayer films

CrN/ZrB2 bilayer films leveraging the wear resistance of CrN and the mechanical properties of ZrB2 were successfully produced and characterized. DC magnetron sputtering was used to deposit CrN/ZrB2 bilayer films with a thickness of approximately 1 μm and various ZrB2/CrN sublayer thickness ratios (TZrB2/TCrN = 10.85, 5.78, 4.50, 2.29, and 1.04). The thickness ratio was controlled by adjusting the deposition times of the individual sublayers. The effects of thickness ratio on the films' phase structures, mechanical properties, and wear resistance were investigated. The ZrB2 sublayer initially formed with a nanocrystalline structure; as its thickness increased, its texture became (001). As the thickness of the CrN sublayer increased, the CrN (111) reflection became more dominant, and the hardness of the CrN/ZrB2 bilayer films decreased from 19.8 to 11.6 GPa. In the CrN/ZrB2 bilayer films, the CrN sublayer was softer than the harder ZrB2 sublayer; specifically, the wear rate of the monolithic ZrB2 film was 6.45 × 10−5 mm3/N·m. This hardness enabled the bilayer films to exhibit excellent wear resistance with wear rates of 1.04–1.68 × 10−6 mm3/N·m. The wear behaviors of the CrN/ZrB2 bilayer films were classified into two tribological mechanisms in accordance with wear track observations. For the samples with high TZrB2/TCrN ratios, the shear mechanism dominated the wear behavior and resulted in the formation of a transfer layer on the worn surface. By contrast, the samples with low TZrB2/TCrN ratios had a ploughing mechanism in which a deformed track was generated on the surface.

Effect of Oxygen Flow Rate, Post-annealing Temperature, and Different Electrolyte Concentrations on WO3 Thin Films Deposited by DC Magnetron Sputtering For Electrochromic Applications

Effect of Oxygen Flow Rate, Post-annealing Temperature, and Different Electrolyte Concentrations on WO3 Thin Films Deposited by DC Magnetron Sputtering For Electrochromic Applications

Fatigue fracture mechanism of sputtered AlSi alloy film by pulsating-tension cyclic loading testing

This paper focuses on investigating the differences in fatigue fracture between sputtered aluminum silicon (AlSi) alloy and pure aluminum (Al) films by means of pulsating-tension cyclic loading tests. AlSi alloy film with 1.0 wt% (wt%) silicon (Si) and pure Al film are prepared at a substrate temperature of 450 ℃ and 260 ℃, respectively, by dc magnetron sputtering. After annealing those films at 490 ℃ under a hydrogen and nitrogen atmosphere for 1 hour, the tensile test specimens are prepared using semiconductor fabrication technologies. Quasi-static tensile tests measure the mean yield strength of 52 MPa and 33 MPa for AlSi and Al films, respectively, which are used as reference stress values for fatigue tests. During fatigue tests, a crack is introduced at the one-side edge of pure Al film specimen and propagates straightly to the other side, whereas a zig-zag crack is observed in AlSi alloy film. The crack propagation rate for AlSi film is around one-tenth of that for pure Al film. The mechanism of fatigue crack propagation is discussed based on element mapping results by energy dispersive X-ray analysis.

TiC and (Ti,Nb)3SiC2 based dual-layer coating on SUS430 for solid oxide fuel cell interconnects

TiC and crystalline (Ti,Nb)3SiC2 based dual-layer is prepared on SUS430 alloy by DC magnetron sputtering followed by annealing at 1000 °C for 20 h. The oxidation of TiC/TNSC coated alloy at 800 °C for 500 h follows the parabolic law with a low rate constant of 5.4 × 10−15 g2 cm−4 s−1. The formed oxide scale is composed of Cr2O3/MnCr2O4 dominated inner layer and outer layer of Nb-doped TiO2 and SiO2 uniform mixture. Owing to the barrier effect of TiC layer and dense oxide scale, outward diffusion of Cr and Mn is efficiently suppressed, resulting in the low Cr content in the outer oxide layer, which is beneficial to the reduced volatilization of Cr oxide. Furthermore, the ASR of the formed oxide scale at 800 °C is 15.87 mΩ cm2, suggesting excellent conductivity. It is concluded that the TiC/(Ti,Nb)3SiC2 coating can significantly improve the oxidation resistannce and electrical property of SUS430 alloy, endowing it potential application as SOFC interconnect protective coating.

Structural, optical and electrochromic properties of WAW films for profound electrochromic applications deposited by DC & RF magnetron sputtering

One of the most frequently used transition conducting oxides (TCO) is indium tin oxide. Indium is very expensive because of the lack of availability. So Most of the researchers focused on cost-effective materials and they have developed Dielectric/Metal/Dielectric (DMD) structures for ITO-free applications. Examples of dielectric materials are AZO, MoO3, TiO2, and WO3. The dielectric material is sandwiched between metals such as Au, Ag, Pt, Cu, and Al. The efficacy of these DMD structures is purely based on the thickness of the dielectric and metal layers. Once the metal layer thickness is more than 15 nm, the transmittance is much less due to the thickness of the material and it will work as a reflector. Moreover, as WO3 is the most widely and frequently used material we focus on the fabrication of WO3/Ag/WO3 (WAW) for replacing TCO in the electrochromic device and making it indium-free. WAW structures are widely used in smart windows, gas sensors, solar cells, photodetectors, etc. For electrochromic applications, these WAW structures showed good transmittance, fast switching speed, best coloration efficiency, and best optical modulation in comparison to WO3/ITO structure and are also cost-effective.

Structural and Optical Properties of Aluminium Nitride Thin Films Fabricated Using Pulsed Laser Deposition and DC Magnetron Sputtering on Various Substrates

Abstract Aluminium nitride thin films were fabricated using pulsed laser deposition and DC magnetron sputtering. Different technological parameters and the effects of different substrates on the optical and structural parameters of AlN samples were studied. An X-ray diffraction study was performed for the layer deposited on the Si3N4 substrate. A high-energy electron diffraction study was also carried out for the layer deposited on a KCl substrate. Transmission spectra of layers on quartz, sapphire, and glass substrates were obtained. An evaluation of the optical band gap of the obtained layers was carried out (Eg form 3.81 to 5.81 eV) and the refractive index was calculated (2.58). The relative density of the film (N1TN-AlN sample) is 1.26 and was calculated using the Lorentz-Lorentz relationship. Layers of aluminium nitride show an amorphous character with a polycrystalline region. It was shown that the properties of AlN films strongly depend on the method, growth conditions, and substrate used.

Tunable structure of TiO2 deposited by DC magnetron sputtering to adsorb Cr (VI) and Fe (III) from water

TiO2 thin films with mixtures of the anatase, rutile, and brookite phases were deposited on glass substrates via magnetron sputtering. Based on XRD and Raman results, the TiO2-0.47 and TiO2-3.47 films principally contained the brookite phase, while the TiO2-1.27 and TiO2-2.13 films were primarily anatase. The capacities of the TiO2 films to adsorb heavy metals were tested with Cr(VI) and Fe(III) solutions, and the maximum Cr(VI) and Fe(III) adsorption capacities were realized with the TiO2-0.47 film (334.5 mg/g) and TiO2-3.47 film (271.3 mg/g), respectively. SEM‒EDS results revealed the presence of Cr and Fe on the surfaces of the films, thus corroborating the ability of the TiO2 films to adsorb and remove heavy metals. They are strong candidates for use in wastewater treatment plants.

Oxidation behavior of Ti2AlC MAX phase-based coating on a γ-TiAl alloy TiAl48-2-2 produced by DC magnetron sputtering

The application of intermetallic γ-TiAl-based alloys is limited by the deterioration in strength and creep resistance as well as reduction in oxidation resistance above 750 °C. The deposition of protective coatings is a promising opportunity to enhance the oxidation resistance or the lifetime with regard to the sustainability by several orders of magnitude. Moreover, additive manufacturing processes could enable the production of components with more complex geometries in the future. Thus, designs of γ-TiAl turbine blades with internal cooling systems could be feasible in the near future. In this context, the deposition of thermal barrier coatings and, therefore, oxidation protective bond coatings became important. MAX phases are of increasing interest as coating materials for high temperature applications due to their unique combination of metallic and ceramic properties. Especially the alumina forming MAX phases such as Cr2AlC, Ti2AlC or Ti2AlN are promising coating materials.In the present work a Ti2AlC MAX-phase based coating was deposited by DC magnetron sputtering. Using three pure elemental target materials - Ti, Al and C and a two-fold rotation, a homogenous all-around coating was applied on the γ-TiAl alloy TiAl48-2-2 with a coating thickness of 10 μm. After the deposition process the stochiometric Ti2AlC coating was X-ray amorphous, therefore a post-heat treatment at 800 °C for 1 h was performed to achieve the desired hexagonal phase. Finally, the MAX-phase coated TiAl48-2-2 alloy was subjected to a cyclic oxidation test at 850 °C in laboratory air. The Ti2AlC MAX-phase coated TiAl48-2-2 alloy exhibits an excellent oxidation behavior, due to the formation of a thermally grown alumina top layer with the desired hexagonal Ti2AlC MAX-phase below. Extensive TEM analyses also showed the dependence of Al2O3 formation on post-heat treatment. θ-Al2O3 with a lower protective effect and the concomitant formation of TiN under the TGO was observed with post-heat treatment in Ar, while post-heat treatment in air lead to the formation of a protective α-Al2O3 layer.

Extremely improved the corrosion resistance and anti-wear behavior of aluminum alloy in 3.5% NaCl solution via amorphous CrAlN coating protection

The low hardness and limited anti-wear of aluminum alloys pose obstacles to their stability and service life, especially in corrosive environments. Here, the amorphous CrAlN coating was first deposited on aluminum alloy by DC magnetron sputtering. The CrAlN coating with 30.2% nitrogen content was dense and prevented the intrusion of oxidation and corrosive fluids, thus greatly improving the anti-corrosion of the coating. The wear rate of the coated aluminum alloy in 3.5% NaCl solution decreased by three orders of magnitude. This work paves the way for constructing amorphous protective coatings on light alloys.

Thermal Conductivity Switching in Pd-Catalyzed Gd and GdH2 Films Upon Gasochromic Hydrogenation and Dehydrogenation

Thermal conductivity switching in Pd-catalyzed Gd hydride films was investigated using in situ analyses of electrical, optical, structural, and thermophysical properties upon gasochromic hydrogenation/dehydrogenation at room temperature. These reactions allow the films to reversibly switch between the metallic (GdH2) phase in the hydrogenated state and the semiconductor (GdH3) phase in the dehydrogenated state. We fabricated three-layered films comprising Pd (5 nm)/Gd or GdH2 (300 nm)/Mo (100 nm) using DC magnetron sputtering using Pd, Gd, and Mo targets, respectively, on unheated synthetic quartz substrates. Ar or mixture of Ar + H2 (H2: 5 % to 50 %) gases were used for the deposition of the Gd or GdH2 films, respectively. The thermal conductivities of the Gd or GdH2 films were analyzed using in situ rear-heating/rear-detection type time-domain picosecond pulsed light heating thermoreflectance measurements by employing a gas mixture of N2/Ar and H2 (H2: 3 %) at 1 atm, which is below the explosive limit for hydrogen. The thermal conductivities of Gd and GdH2 films were measured for one and two hydro-/dehydrogenation cycles, respectively. The thermal switching ratios of the ON state thermal conductivity to the OFF state thermal conductivity were 6.4 and 2.9–5.4 for the Gd film and the GdH2 (H2: 5 %–50 %) films, respectively. The thermal conductivity of the Gd hydrides films changed along with those estimated from the Wiedemann–Franz Law and electrical conductivities.

Tribological properties of silver coatings prepared by low temperature pulsed DC magnetron sputtering and electroplating for aero-engines fasteners

In this work, the causes of failure of electroplating silver coatings on aero-engine nuts were explored. And the microhardness of low temperature pulsed DC magnetron sputtering silver coatings was increased by 25%, and the bonding force was increased by about 1.2 times. At high temperature, the friction coefficients of magnetron sputtering silver coatings was about 20% lower than that of electroplating silver coatings, and the wear volume was about 90% lower than that of it at maximum. The wear mechanism of magnetron sputtering silver coatings was mainly abrasive wear, while that of electroplating silver coatings was mainly adhesive wear. Besides, the results of molecular dynamics showed that silver coatings would move and aggregate in layers during the friction.

Electrochromic properties of InON thin films prepared by DC magnetron sputtering

Electrochromic properties of InON thin films prepared by DC magnetron sputtering

Mechanical properties of Xe-ion-irradiated high-entropy-alloy-based multilayers

In this Letter, we investigate the mechanical stability of HEA-based multilayers after Xe-ion irradiation. CrFeCoNi/TiNbZrTa metallic and nitride thin films with a bilayer thickness of 30 nm were grown by reactive dc-magnetron sputtering on Al2O3(0001) substrates for irradiation studies and on Si(100) substrates for other characterizations. The films were subjected to 3-MeV Xe-ion irradiation at room temperature (RT) and at 500 °C. The crystal structure and mechanical properties of the films before and after irradiation were studied by x-ray diffraction and nanoindentation. Before irradiation, both the metallic and nitride multilayers displayed a lower hardness (7 and 20 GPa, respectively). Annealing at 500 °C for 150 min increased the hardness of the multilayer samples, but it also induced intermixing of elements between the sublayers of the metallic multilayer. Irradiation hardening was observed only in the metallic multilayer at room temperature. When comparing the effects of irradiation damage vs the effects of annealing on the mechanical properties, it was observed that annealing the multilayers had a more pronounced effect.

Effect of Substrate Temperature and Deposition Power on the Surface Morphology and Optical Properties of ZnO:Mg Thin Films Deposited by DC Magnetron Sputtering

Magnesium doped zinc oxide (ZnO:Mg) thin films were deposited on soda lime glass slides by DC magnetron sputtering method. Atomic force microscope (AFM), and UV/VIS spectrophotometer were used to investigate the effect of sputtering power and substrate temperature on the surface morphology and optical properties of ZnO:Mg thin films. AFM images revealed that sputtering power and deposition temperature have significant influence on surface morphology of the ZnO:Mg thin films. For all sputtering powers and substrate temperatures investigated, ZnO:Mg films had peak transmittance above 85%. Samples deposited at 110 W sputtering power and 450 °C substrate temperature showed the best peak transmittance of > 90% at 560 nm (visible range). Optical band gap of ZnO:Mg films was in the range of 3.44– 3.69 eV depending on the substrate temperature. The results indicated the potential of the films for transparent conductor applications.

Effect of sputtering pressure and oxygen content on the electrochromic properties of NiO films by DC magnetron sputtering

In this study, NiO films were fabricated using DC magnetron sputtering under various conditions of sputtering pressures and oxygen contents. The effects of the sputtering pressure and oxygen content on the structure, morphology, optical properties, and electrochromic performance of the NiO films were analyzed using X-ray diffraction, scanning electron microscopy, atomic force microscopy, UV spectrophotometry, and electrochemical workstation. The grain size, thickness, and roughness of the NiO films showed decreasing trends with increasing sputtering pressure; however, these factors showed significant variations with increasing oxygen content. The results demonstrated that when the sputtering pressure was 0.8 Pa, the prepared films were characterized by loose and porous surfaces, high roughness, crystallinity, and excellent electrochromic properties. The optical contrast was 75.34 % (at 550 nm), coloration efficiency was 14.86 cm2/C, coloring time was 2.09 s, and bleaching time was 2.05 s. Furthermore, good cycling stability was achieved.