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Graphical abstract Highlights • W-Cu thin films are GLAD co-sputtered. • A dense structure is obtained at the film/substrate interface. • W-Cu Janus-like architectures are produced. • Wet chemical etching of Cu favors anisotropic resistivity. Abstract Two immiscible metals (W and Cu) were deposited using two metallic targets by GLAD co-sputtering. A wet chemical etching technique was implemented to remove the copper and modify the typical inclined microstructure into a more porous architecture. The electrical resistivity behavior of the co-sputtered W-Cu film was characterized as a function of temperature before and after wet chemical etching. The results show that the columnar microstructure exhibits metallic-like electrical properties. The average DC electrical resistivity ρ changes from 1.66 × 10−5 Ωm to 4.28 × 10−5 Ωm after etching. The anisotropy at room temperature is A = 1.8 ± 0.1 for as-deposited W-Cu film and reaches 2.8 ± 0.1 after the etching procedure. [ABSTRACT FROM AUTHOR]

[Display omitted] • P-type BaZrS 3 thin film via Ba-poor growth conditions was prepared; • Ruddlesden-Popper Ba 3 Zr 2 S 7 thin film was prepared; • BaZr 1- x Ti x S 3 can tune E g from 2.2 to 1.5 eV, a value suitable for absorbers; • Sputtering-annealing is a useful method for chalcogenide perovskite thin films. BaZrS 3 is an emerging chalcogenide perovskite that possesses excellent light absorption and carrier transport abilities comparable with the halide perovskites. Besides, it shows better stability and lower toxicity. However, BaZrS 3 is only reported as n-type conductivity in previous studies. Lack of p-type conductivity limits its application into solar cells or other complex devices. In addition, strategies to tailor its band gap (∼1.8–2.2 eV) to optimal range (∼1.4–1.5 eV) for solar absorbers are not well established. In this work, for the first time, we demonstrate p-type conductive BaZrS 3 thin film with the hole concentration and mobility as high as ∼1018 cm−3 and 30 cm2/Vs, respectively, and the Ba vacancy was the most probable defect contributing to the p-type conductivity. Ruddlesden-Popper Ba 3 Zr 2 S 7 thin film and orthorhombic BaZr 1- x Ti x S 3 alloy thin film are also prepared by co-sputtering from BaZrS 3 and BaS/BaTiS 3 targets. Inspiringly, 4% Ti substitution for Zr can tune the band gap of BaZr 1- x Ti x S 3 from 2.2 to 1.5 eV, a near ideal value for photovoltaic absorbers according to Shockley − Queisser limit. Successful optoelectronic tuning strategies for chalcogenide perovskite in this work may pave the way for its application into complex optoelectronic devices like solar cells. [ABSTRACT FROM AUTHOR]

In this paper, in-situ fluorine-doped ZnSnO (ZTO:F) thin films prepared by co-sputtering are proposed. It was found that the F had been successfully introduced into the ZTO thin films and distributed uniformly in the bulk. The corresponding top-contact bottom-gated ZTO:F thin film transistors (TFTs) were fabricated with an annealing temperature of 350 °C. The fabricated TFTs exhibit a field-effect mobility of 14.2 cm2V−1s−1, on-off ratio of over 109, and subthreshold swing (SS) as low as 87 mV/decade due to the incorporation of F. In addition, the bias stability of fabricated TFTs was also examined and the V t h shifts under negative gate bias stress are not more than ±0.1 V even without any passivation. It is expected that the In-free ZTO:F amorphous oxide semiconductor and the corresponding TFTs have potential for low-cost and environmentally safe fabrication. • ZTO:F TFTs were prepared by co-sputtering, exhibiting competitive electrical properties and excellent reliability. • This in-free ZTO:F TFTs exhibited considerable potential for low-cost and environmentally safe fabrication. [ABSTRACT FROM AUTHOR]

In this study, we investigated the structural properties of TeO2-ZnO (TZ) and TeO2-ZnO-Au (TZA) thin films sputtered under different oxygen concentrations and either annealed or not annealed at 325 °C in air for 10 or 20 h. The lattice changes of the tellurium oxide were shown to be inherent in the polymorph properties of the α and β phases. The β phase was formed for null oxygen flow and the α phase was formed for different oxygen flows (0.5–7.0 sccm) during TZ and TZA sputtering. Au was encountered in its single phase or as AuTe2. The annealing had very little influence on the α and β phases for both TZ and TZA. It is worth noting that SiO2 and orthotellurate anions are both formed for not-null oxygen flow. An electrochemical mechanism was proposed to explain the SiO2 growth at the TZ/Si or TZA/Si interface, taking the orthotellurate anion as oxidizing agent into account.

Metal/NiO-Smarium-doped ceria (SDC) nano-composite thin film anodes were deposited on anodic aluminum oxide by co-sputtering to enhance the in-plane current-collecting ability and investigated by varying the composition of metal materials (Pt and Au). Full fuel cells with these nano-composites were fabricated and tested at 500 °C. Columnar anodes with a sponge structure were fabricated by varying the DC sputtering source power and they were thermally stable at the operating temperature. By adding metal material, the ohmic resistance, including the current collecting resistance, was drastically reduced and the polarization resistance also decreased. The nano-composite electrode with a Pt content of 61 at% showed the highest performance, which is a maximum power density of 212.5 mW/cm2 at 500 °C. In addition, Au was considered to reduce the current collecting resistance and the corresponding power density was 3 times higher than that with the NiO-SDC anode.

Complex multilayer film structures were fabricated through a custom-built angular DC magnetron co-sputtering system. In this system, separate Cu, Al, and brass (Cu + Zn) targets were mounted on three magnetron guns, working in conjunction with a rotating substrate. This study aimed to compare the properties of films with intricate structures, which were sputtered onto glass slides and polypropylene substrates. The sputtering process was optimized using a Box-Behnken design, considering three variable operating conditions: substrate rotation speed, sputtering time, and sputtering voltage. The Analysis of Variance (ANOVA) results for film thickness and roughness, sputtered with three different materials onto glass slides and polypropylene (PP) substrates, indicated that all three independent variables significantly influenced the optimum response, with P -values less than 0.05 (<α = 0.05). The optimal conditions for maximizing the thickness and roughness of the sputtered film on PP substrates differed from those obtained for the thin-film properties of the sputtered film on glass slide substrates. Top-view images of the surface morphology revealed a dense and granular structure for the film deposited on the glass slide, whereas some grooves between the grains and fractures were observed in the film on the PP substrate. Additionally, it was evident that these sputtered multilayer films exhibited a complex structure, as reflected in the uniform and homogeneous distribution of Cu, Al, and Zn atoms on both glass slides and PP substrates., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Graphical abstract The transfer curves of TiZO TFTs (a) as a function of Ti sputtering power with ZnO sputtering power fixed at 50 W and (b) as a function of ZnO sputtering power with Ti sputtering power fixed at 80 W. Highlights • TiZO TFTs were fabricated successfully by the cosputtering of Ti and ZnO targets. • Effects of sputtering power on the performance of TiZO TFTs were investigated. • TiZO thin films were characterized using XRD, AFM and SEM, which agreed well with the variation of device performance. • The optimal electrical performance was obtained at 60 W of ZnO sputtering power and 80 W of Ti sputtering power. • The TiZO material, as a kind of In-free oxide semiconductor, shows huge potential to be the active layer of TFTs. Abstract Titanium doped zinc oxide (TiZO) thin-film transistors (TFTs) were fabricated with the active layer deposited by the cosputtering of Ti and ZnO targets. We fabricated TiZO TFTs under various sputtering powers, effects of which on the performance of TiZO TFTs were investigated. The results suggest that the effective Ti doping concentration is significant for excellent electrical properties. The optimal electrical performance was obtained at 60 W of ZnO sputtering power and 80 W of Ti sputtering power. The changes in the crystalline structure, surface morphology and optical transmittance of TiZO thin films were examined according to the sputtering power, which agreed well with the variation of device performance. [ABSTRACT FROM AUTHOR]

Abstract In this study, a combinatorial approach was used to develop cathode materials with improved performance at temperatures in the range 500–700 °C. A thin film composite cathode library was obtained by co-sputtering of LSC-113 and LSC-214 onto suitably positioned substrates each with controlled compositions. The cathode library was screened with an electrochemical impedance spectroscopy using symmetric cells. The study showed that the compositions with volume fractions in the range 0.40 < LSC-214 < 0.60 is particularly significant in yielding cathodes of improved performance. Refocusing the combinatorial screening to this range yielded LSC-113:LSC-214 = 0.45:0.55 as the most favorable compositions. Taking ASR = 0.15 Ω·cm2 as a useful benchmark, the study showed that cathodes in this range may be used at temperatures as low as 575 °C. It was further shown that composite cathodes have amorphous structures in co-sputtered conditions, and could remain so when used at reduced temperatures. At temperatures close to 700 °C the amorphous cathode turns into nanocrystalline two-phase structure with grains not more than 10 nm in size. Highlights • Amorphous cathodes were co-sputtered in LSC-113 - 0.10 < LSC-214 < 0.90. • Cathodes remained amorphous when used at low temperature. • When used at 700 °C, the cathode crystallized with grain size < 10 nm. • The cathode LSC-113 - 0.45 LSC-214 was the most favorable composition. • With ASR = 0.15 Ω·cm2, the cathode could operate at temperatures as low as 575 °C. [ABSTRACT FROM AUTHOR]

We investigate the deposition of TiWSiN x thin films by means of the method of reactive magnetron co-sputtering, setting the nitrogen flow ratios N2/(Ar + N 2 ) at 4.8%, 9.1%,16.7 and 33.3%. The crystallographic structure of the films was established through X-ray diffraction (XRD), the morphology and topography were evaluated through scanning electron microscopy (SEM) and atomic force microscopy (AFM), the chemical composition was evaluated through X-ray diffraction and X-ray photoelectron spectroscopy, the mechanical properties were evaluated by nanoindentation, and the wear resistance was studied via nanowear and pin-on-disk. It was found that films deposited between 4.8% and 16.7% nitrogen flow ratio exhibited an amorphous phase. As the nitrogen was increased, the films evolved into a mixture of amorphous Si 3 N 4 and crystalline TiWN phase. Moreover, the film morphology changed to fine columnar as the nitrogen flow ratio increased. As a general observation, the hardness, resistance to plastic deformation (H 3 /E 2 ), and residual stress of the samples increased as the nitrogen flow ratio increased. The maximum hardness, resistance to plastic deformation, and residual stress were 22 ± 0.4 GPa, 213 ± 20 MPa, and 1.4 ± 0.01, respectively. The lowest nanowear volume (0.47 µm 3 ) and wear rate (11 ± 8 10 −9  mm 3 /N mm) were obtained for films deposited at high nitrogen flow ratios. The lowest friction coefficient (0.15) was recorded for films deposited at 16.7% nitrogen flow ratio. [ABSTRACT FROM AUTHOR]

Abstract Aluminum gallium oxide (AGO) films were deposited on c -plane sapphire by co-sputtering of Al and Ga 2 O 3 targets at a substrate temperature of 600 °C, and then annealed at 900 °C to enhance their crystal quality. The effect of DC power (0, 5, 10, 30, 50 and 70 W) for Al target on the structural, optical and compositional characteristics of AGO films were investigated. After annealing, the films prepared at the DC powers of 0–50 W for Al target all exhibited the single crystalline structure with the (−201) plane family. The annealed film grown at the DC power of 10 W possessed the highest crystal quality than the others. With increasing the DC power from 0 to 70 W, the Al composition of AGO film increased from 0 to 6.08 at.%, while its bandgap increased from 4.89 to 5.19 eV. X-ray photoelectron spectroscopy studies indicate the intensity of Ga 2p 3/2 peak (1117.9 eV) for the AGO film decreases, whereas the intensity of Al 2p peak (74.6 eV) increases with increasing the DC power. The metal-semiconductor-metal photodetector with the annealed AGO film deposited at the DC power of 10 W possesses the largest photocurrent of 5.7 × 10−9 A and the on/off current ratio (I on /I off ) of 1.5 × 104 (@2 V and 230 nm). The better optoelectronic performance of this device was attributed that the AGO film (DC power: 10 W) had a higher crystal quality, the O/(Al+Ga) ratio close to the optimum value of 1.5. Our results present the AGO films can be successfully prepared via sputtering technique, which are highly potential for deep-ultraviolet applications. Highlights • The effect of sputtering power on the AGO films' properties was investigated. • The bandgap values of these sputtered AGO films can reach to 4.89–5.19 eV. • XPS reveals the Ga 2p3/2 peak becomes weak by increasing the DC power of Al target. • Meanwhile, the Al 2p peak becomes strong with increasing the DC power of Al target. • AGO film (DC power: 10 W) has higher crystal quality and optimum O/(Al+Ga) ratio. [ABSTRACT FROM AUTHOR]

Highlights • Nano-crystalline Si thin film was fabricated by Si-Al co-sputtering and thermal annealing. • p+-n thin film Si solar cell was fabricated by sputtering and thermal annealing in three steps. • A model was proposed for describing aluminum-induced crystallization by co-sputtering (AICCS). • It was shown that AICCS is simpler and eco-friendlier than aluminum layer exchange (ALILE). Abstract Fabrication of nano-crystalline thin film solar cell by co-sputtering of silicon and aluminum, and metal induced crystallization is reported in this paper. After a brief introduction on magnetron sputtering and aluminum-induced crystallization techniques, it discusses the drawbacks of "aluminum induced layer exchange" concept as the common method for fabricating poly-Si thin films; and proposes Si-Al co-sputtering as a simple alternative fabrication method. Then a three-steps process is introduced for the fabrication of "Al electrode/n-Si wafer/p-Si thin film/Al electrode" solar cell. Material and electrical characterizations of the fabricated p-Si thin films are done by Raman spectroscopy, X-ray diffraction, optical microscopy, scanning electron microscopy and Hall Effect measurement to study the crystallization ratio, grain size, morphology, carrier density and mobility of the prepared films, respectively. The best fabricated samples show a crystallization ratio of 88% and the largest grain size of 68 nm. The hole concentration in the films is in the order of 1018 to 1019 cm−3 with a maximum mobility value of 17 cm2/V s. Then, photovoltaic properties of the fabricated solar cells are determined by under dark and illumination J-V curves, and external quantum efficiency measurements. Dark J-V curve of the best sample represents an ideality factor of 1.39, rectification ratio of 1993 at ±1 V and reverse saturation current density of 62.1 nA/cm2 which confirms the formation of a good p-n junction. The illuminated J-V curve under AM1.5G conditions exhibits a photovoltaic conversion efficiency of 6.02% for the best sample, with a short circuit current density of 24.9 mA/cm2 and open circuit voltage of 456 mV. The external quantum efficiency of this sample reaches to more than 59% at the wavelength of 700 nm. Finally, a simple model is proposed to describe the formation of nano-crystalline Si thin film, deposited by Si-Al co-sputtering, during the thermal annealing. [ABSTRACT FROM AUTHOR]

Zinc magnesium oxide, Zn 1− x Mg x O, is a desirable candidate for a buffer/window layer in thin film solar cells. We deposited Zn 1− x Mg x O film with hexagonal structure by co-sputtering of ZnO and Mg targets. Band gap of the Zn 1− x Mg x O films was found to increase from 3.48 to 3.83 eV with the increase in Mg content in the film. We used X-ray photo-electron spectroscopy (XPS) to examine the interfaces formed between such Zn 1− x Mg x O films and the recently reported cubic structured SnS (SnS-CUB) thin films of bandgap 1.72 eV. The valence band maxima of the materials determined from XPS show that the conduction band offset (CBO) for Zn 0.88 Mg 0.12 O/SnS-CUB interface is 0.39 eV. The CBO, 0.52 eV of Zn 0.88 Mg 0.12 O/SnS-CUB hetero junction was also calculated from electron affinities of Zn 0.88 Mg 0.12 O and SnS-CUB thin films which is in agreement with the CBO calculated from the XPS measurements. [ABSTRACT FROM AUTHOR]

In the present work co‐sputtering from ceramic and metallic targets is used to reduce the oxygen content in aluminium doped zinc oxide. Films with thickness between 200 and 220 nm are sputtered at 100 and 250 °C and investigated by X‐ray diffraction, energy dispersive spectroscopy, and Hall measurements. It is found that reducing of the incorporated oxygen in the film leads to higher carrier concentration, mainly due to better effective activation of Al donors. Higher temperatures result in better carrier mobility due to improving the crystallinity. The best resistivity of 1.4 × 10−3 Ω cm of the highly transparent film prepared at 100 °C is achieved. A larger oxygen reduction leads to lower resistivity, but also results in the significant deterioration of transmittances. [ABSTRACT FROM AUTHOR]

A series of Cu-W films with the W content higher than 17.2 at% were prepared by magnetron sputtering focused co-deposition technology. The micro-structures and nanoidentation hardness of the films were investigated. Except for the fcc, amorphous and bcc phases, a novel multilayered structure has been observed at the range of about 17.2–90 at% W. Within the multilayered structure, the high-density interfaces can inhibit the motion of dislocations, which resulted in the hardness at least 2 GPa higher than that of the mixing rule. Depending on different microstructures, the hardness curve of the Cu-W films can be divided into three regions instead of the linear increase with the W content. From 17.2–40 at% W, the hardness increased slowly due to lots of amorphous phase. Within 40–65 at% W, the hardness increased linearly, which was caused by the gradually obvious multilayered structure and decreasing amorphous content. Above 65 at% W, single-phase body-centered cubic (bcc) films were observed. In this region, the upward trend of hardness slowed down due to the porous columnar structure and gradually disappeared multilayered structure. [ABSTRACT FROM AUTHOR]

Higher manganese silicide (HMS) MnSi γ films with varying γ (1.65 ≤  γ  ≤ 3.23) were deposited on oxidized Si wafers at 703 K by radio frequency (RF) magnetron co-sputtering of Mn and Si targets. As-deposited films were annealed at 1273 K for 3min using a lamp annealing system, and the thermoelectric (TE) properties were measured in the temperature range from room temperature to 1073 K. All the MnSi γ films were p-type below about 550 K, but the polarity converted to n-type at higher temperatures. Moreover, the power factor ( PF ) of the polarity-inverted films was exceptionally high, reaching the maximum value of 12.3 mW/K 2 m in the annealed MnSi 2.04 film. In case of the as-deposited films, the PF in the p-type regime ( PF p ) grew larger as the Si/Mn molar ratio γ approached the stoichiometric value of 1.73, while the PF n became vanishingly small. In contrast, the PF n of the annealed films remained very high even in the Mn-rich film ( γ  < 1.73), such that 9.6 mW/K 2 m was obtained from the MnSi 1.65 film. Hall measurement at elevated temperatures (≤773 K) showed that electron mobility was greatly increased after the annealing, which has produced unusually high PF n . The HMS phase was composed of Mn 4 Si 7 and Mn 11 Si 19 , but regions of unidentified phase were also confirmed by transmission Kikuchi diffraction (TKD) analysis, the proportion of which was larger in the Si-rich films. The modification of the band structure induced by defects and structural disorder of the Mn and/or Si sublattice are supposed to be the origin of this novel phenomenon. [ABSTRACT FROM AUTHOR]

The microstructures and mechanical behavior of high-temperature co-sputtered Cu/Mo nanocomposites were investigated and compared with Cu/Mo multilayers. The co-sputtered nanocomposites present hierarchical architectures with bicontinuous intertwined Cu/Mo phases, the feature size of which can be tuned from 35 to 3 nm by changing the deposition parameters. After indentation, shear bands were found in the multilayers but not in the hierarchical nanocomposites. In situ nanocompression tests in Transmission electron microscopy showed that the hierarchical nanocomposite containing fine-length-scale intertwined Cu/Mo phases has very high strength. The hierarchical structure is proposed to play an important role in suppressing shear band formation. [ABSTRACT FROM AUTHOR]

ZnO:Al is widely used as transparent conductive oxide (TCO) layer in several electronic and optical devices. To widen bandgap energy (E g ) of ZnO:Al, Mg was introduced to form Zn 1 − x Mg x O:Al. In this work, the Zn 1 − x Mg x O:Al films with different [Mg] / ([Mg] + [Zn]) ratios (Mg content (x)) on soda-lime glasses and polycrystalline Cu(In,Ga)Se 2 thin films were prepared by radio frequency magnetron co-sputtering of ZnO:Al and MgO targets. The power density applied to ZnO:Al target was constant at 144.3 W/cm 2 , whereas that applied to MgO target is varied from 0 to 183.7 W/cm 2 to change the [Mg] / ([Mg] + [Zn]) ratio from 0 to 0.205. It is demonstrated that E g of the Zn 1 − x Mg x O:Al is increased with the [Mg] / ([Mg] + [Zn]) from 0 to 0.205, while the basic crystal structure is ZnO. The Zn 1 − x Mg x O:Al films with small [Mg] / ([Mg] + [Zn]) ratios of approximately 0.064–0.139 possess the better film quality and higher Hall mobility than those of ZnO:Al since their crystalline diameters are enhanced with the decreased deep-defect levels. With the small [Mg] / ([Mg] + [Zn]) up to 0.139, the carrier concentration is decreased, which is beneficial to lower the free carrier absorption, while the resistivity is kept low. Consequently, the Zn 1 − x Mg x O:Al films with the small [Mg] / ([Mg] + [Zn]) ratio (about 0.064–0.139) are promisingly utilized as TCO layer. [ABSTRACT FROM AUTHOR]

Skutterudite CoSb 3 material exhibits excellent thermoelectric properties for thermoelectric application. In this work, CoSb 3 thin films were fabricated by direct current magnetron co-sputtering. The composition of thin films was controlled by regulating the deposition power of both Co and Sb. Then the as-deposited Sb-excess sample was chosen to process post-annealing. High-resolution transmission electron microscopy and X-ray diffraction, together with Raman analysis, demonstrate that the annealed samples have well-crystallized and nano-sized skutterudite CoSb 3 structure. Hall measurement shows that specimens are P-type semiconductor. Both of the increasing of Seebeck coefficient and electric conductivity can be obtained when the samples annealed at appropriate temperature, indicating that thermally can improve its thermoelectric properties due to well-crystallized and nano-sized structure. [ABSTRACT FROM AUTHOR]

It is important to design and fabricate nanoporous metals (NPMs) with optimized microstructures for specific applications. In this contribution, nanoporous coppers (NPCs) with controllable thicknesses and pore sizes were fabricated via the combination of a co-sputtering of Cu/Ti with a subsequent dealloying process. The effect of dealloying time on porous morphology and the corresponding surface enhanced Raman scattering (SERS) behaviors were systematically investigated. Transmission electron microscopy (TEM) identified the presences of the gaps formed between ligaments and also the nanobumps on the nanoparticle-aggregated ligament surface, which were likely to contribute as the “hot spots” for electromagnetic enhancement. The optimal NPC film exhibited excellent SERS performance towards Rhodamine 6G (R6G) with a low limiting detection (10 −9 M), along with good uniformity and reproducibility. The calculated enhancement factor of ca. 4.71 × 10 7 was over Au substrates and comparable to Ag systems, promising the proposed NPC as a cheap candidate for high-performance SERS substrate. [ABSTRACT FROM AUTHOR]

Cu doping can change the properties of ZnO thin film. In previous studies, most papers reported on moderate doping level of Cu and used ZnO as a target with Cu chip incorporated into it. This paper reports the effects of moderate and higher Cu doping level (12%–28%) on the ZnO thin film, fabricated by using magnetron co-sputtering technique of pure ceramic ZnO and metal Cu target at room temperature. The effects of different Cu concentration on the crystal structure, surface morphology, optical properties and electrical properties were investigated by using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), ultraviolet-visible (UV-VIS) spectrophotometer and Hall measurement with four-point Van der Pauw configuration respectively. XRD results indicated that ZnO thin films with hexagonal wurtzite structure was fabricated. Moderate Cu-doped ZnO has stronger preferential orientation towards c-axis compared to heavily doped and pure ZnO. In heavily Cu-doped region (24%-28%), there are secondary phases detected, Cu metallic (111). Transmittance of all films in the visible region are more than 75%. Results obtained from transmittance data are used to calculate the optical band gap of the thin film. Energy gap reduction is observed when Cu is introduced into ZnO. [ABSTRACT FROM AUTHOR]

This work discusses the growth characteristics, composition, and photoluminescence properties of Zn-doped Ga 2 O 3 (ZnGaO) films. The idea of doping of Zn divalent cation in β-Ga 2 O 3 is to modulate the n-type conductivity of β-Ga 2 O 3 to p-type. Therefore, a series of ZnGaO films with varying Zn contents have been deposited on sapphire substrates using co-sputtering of Ga 2 O 3 and Zn targets at the substrate temperature of 400 °C. The X-ray diffraction analysis revealed that divalent Zn dopant is stable up to 8.62% in ZnGaO films. The X-ray photoelectron spectroscopy defined the increasing amount of Zn content in ZnGaO films. The lowest defect formation energy per atom by first-principles calculations indicates that the favourable site of Zn atoms is substitutional Ga tetrahedral site (T-site) in ZnGaO. The photoluminescence (PL) spectra exhibited that the peak emission wavelength of β-Ga 2 O 3 can be shifted with the inclusion of divalent Zn dopant in Ga 2 O 3 films, which is in accordance with the energy diagram and charge density distribution, indicating the Zn substituted T-site Ga are leading to more defect states, and inducing green luminescence in PL spectra. The ZnGaO films exhibited positive Hall coefficient, which verifies the p-type nature of films. ZnGaO films demonstrate a unique ability to realize p-type characteristics among emerging wide bandgap semiconductors, extending its applications at the forefront of contemporary optoelectronics technologies. [Display omitted] • Co-sputtering technique was used to deposit Zn-doped Ga 2 O 3 films. • The green luminescence was observed in Zn-doped Ga 2 O 3 films. • First-principles investigations were performed to verify the emission mechanism. • Zn atoms like to substitute Ga T-sites due to the lowest defect formation energy. • The positive Hall coefficient verified the p-type nature of Zn-doped Ga 2 O 3 films. [ABSTRACT FROM AUTHOR]

• A high-efficiency photocatalytic of Zn x V y O films prepared by co-deposition. • The n-n heterojunctions combined with Zn x V y O and ZnO were prepared. • The photocurrent of Zn x V y O (15%) reached about 2.2 times than that of undoped ZnO. • The photocurrent response of heterojunctions is improved about 68%. Solar energy utilization is regarded as one of the most promising and cost-effective approaches to solve energy and environmental problems. In the present work, a series of V-doped ZnO films with different V contents are produced by co-sputtering deposition for the photocatalytic applications. It is found that the introduction of V elements has a significant effect on the morphology, band structure and photoelectric properties of the material. The photocurrent response of Zn x V y O (V∼15%) sample enriches a value of 0.47 mA/cm2 at a constant voltage of 1.23 V (vs. RHE), which is about 2.2 times higher than that of undoped ZnO. In addition, the n-n heterojunctions combined with Zn x V y O and ZnO are prepared. Compared with Zn x V y O (V∼15%) sample, the photocurrent response of Zn x V y O (V∼15%)/ZnO is further improved by about 68%, reaching 0.79 mA/cm2. It is confirmed that the Zn x V y O (V∼15%)/ZnO heterojunctions structure could effectively inhibit the recombination of carriers and enhance the oxidation reaction. [ABSTRACT FROM AUTHOR]

Photoelectrochemical energy conversion is the ultimate approach for converting sunlight energy into value-added chemical fuels. The path of achieving economically feasible, highly efficient, and earth-abundant material-based photoelectrodes can be a driving force for realizing PEC on a global scale. Copper-based delafossite photoelectrodes are attractive candidates because they exhibit appropriate absorption properties and structural stability in an aqueous system. In this study, delafossite Cu x Fe 2−x O 2 films of varying compositions ranging from 0 ≤ x ≤ 2 are prepared by adjusting the Cu/Fe composition via radio frequency plasma co-sputtering to evaluate the fundamental optoelectronic properties. The optical bandgap of the CuFeO 2 films tuned from 1.4 to 1.65 eV, with the maximum carrier concentration of 5.9 × 1017 cm−3 noticed in Cu 1.5 Fe 0.5 O 2 film. The X-ray photoelectron spectroscopy measurements confirm the existence of a high level of oxygen-deficient sites in CuFeO 2 film photoelectrodes that are suitable for PEC performance. The fabricated non-stoichiometric photoelectrode exhibits an excellent hydrogen evolution reaction of 4.3 μmol/hcm2, nearly 1.8 times improvement over Cu 2 O photoelectrode with a long-term photostability even in an aqueous system. The ability to fabricate tunable electronic structures photoelectrodes along with oxygen-deficient surface defects facilitates to localize band edge closer to the HER of water, and the Fermi level is slightly away from the reduction potential of Cu 2 O, which supports to improve PEC performance by suppressing photo-induced corrosion to retain greater photostability. [Display omitted] • Delafossite CuFeO 2 films are fabricated via RF plasma co-sputtering. • Element compositions are controlled by adjusting the sputtering current. • The maximum hydrogen evolution rate is measured to be 4.3 μmol/h∙cm2. • The Cu 1.5 Fe 0.5 O 2 film exhibits 85 % higher HER than the other photoelectrodes. • The ratio of Cu/Fe composition tunes the band structure suitable for water-splitting. [ABSTRACT FROM AUTHOR]

Recently, the photovoltaic (PV) and photoelectrochemical (PEC) cell has engrossed cumulative attention for clean and low-cost sustainable energy. Here, we propose transparent PV (TPV) and PEC (TPEC) based on sputtered BiVO 4 semiconducting thin films to unite electric power and hydrogen generation for see-through energy systems. The TPV and TPEC devices performed better under white light illumination when doped with Mo, and showed average visible transmittance of ∼60%. Such enhancements are due to the Mo doping in BiVO 4, which offers better optoelectronic properties suitable to TPV and TPEC devices than BiVO 4 thin films. Mo:BiVO 4 -based TPV-TPEC device shows a high open circuit voltage of 0.43 V with a fill factor value of 33.8% and a short-circuit current density of 0.415 mA/cm2, attributed to the enhanced absorption for blue wavelength photons, indicating stable and safe onsite power production. The structural, optical, and electrical performances of BiVO 4 films were studied and compared with its Mo:BiVO 4. These co-sputtered Mo:BiVO4-based TPV and TPEC devices can further enhance the robust power-generating systems for see-through onsite energy production. [Display omitted] • BiVO 4 and Mo:BiVO 4 thin film-based transparent photovoltaic (TPV) and photoelectrochemical (TPEC) cell. • Mo:BiVO 4 -based TPV exhibited 60% of average visible transparency and better photovoltaic performance. • TPV had the 0.43 V of open-circuit voltage and onsite power density of 56 μW/cm2 under white illumination. • A dark-to-photocurrent ratio of > 105 was confirmed at the self-operation condition. [ABSTRACT FROM AUTHOR]

A new simple way for tuning the phase transition temperature (PTT) of VO2 thin films has been proposed to solve the problem of changing the doping ratio by using the dual-target co-sputtering method. A series of samples with W doping ratios of 0%, 0.5%, 1%, 1.5% and 2% have been fabricated by sputtering V films with the power of pure and 2% W-doped V targets from 500 W: 0 W, 500 W: 250 W, 500 W: 500 W, 250 W: 500 W to 0 W: 500 W respectively and then annealed in an oxygen atmosphere to form VO2. The XRD results of both pure and W-doped VO2 samples reveal that VO2 forms and is the main component after annealing. The PTT can be tuned by controlling the sputtering power ratio of the pure and doped targets. It can be tuned easily from 64.3 °C to 36.5 °C by using the pure and 2% W-doped targets for demonstration, with W doping ratios from 0% to 2%. It is also valid for other doping elements and is a promising approach for the large-scale production of sputtering.

In this study, amorphous indium gallium oxide thin-film transistors (IGO TFTs) were fabricated by co-sputtering. Three samples with different deposition powers of the In2O3 target, namely, sample A with 50 W deposition power, sample B with 60 W deposition power, and sample C with 70 W deposition power, were investigated. The device performance revealed that oxygen vacancies are strongly dependent on indium content. However, when the deposition power of the In2O3 target increased, the number of oxygen vacancies, which act as charge carriers to improve the device performance, increased. The best performance was recorded at a threshold voltage of 1.1 V, on-off current ratio of 4.5 × 106, and subthreshold swing of 3.82 V/dec in sample B. Meanwhile, the optical properties of sample B included a responsivity of 0.16 A/W and excellent ultraviolet-to-visible rejection ratio of 8 × 104. IGO TFTs may act as photodetectors according to the results obtained for optical properties.

A narrow process window for the fabrication of p-type semiconductors is one of the major challenges in implementing tin oxide (SnO x ) in thin film transistor applications. The SnO x lattice was doped with Al to widen the process window and enhance the p-type channel thin film transistor performance with co-sputtering process. A change in the growth orientation direction with the presence of Al in SnO x thin films was observed in the grazing-incidence X-ray diffraction data. The changes in the oxidation states of Sn ions were determines by X-ray photoelectron spectroscopy. With increasing Al concentration, the ratio of Sn 4 + in the Sn peaks decreases indicating that the SnO x film has improved p-type properties. These changes led to an improvement of the electrical properties such as output characteristic, field effect mobility, subthreshold swing, and positive shift of threshold voltage. [ABSTRACT FROM AUTHOR]

We fabricated double-active layer amorphous Si-doped indium zinc oxide thin-film transistors. The electrical properties of devices with various thicknesses of the layer with lower SiO 2 content were investigated. Compared with the single layer, the threshold voltage of the double layer was close to 0 V. As the thickness of front channel increased, the saturation mobility increased, and the subthreshold swing improved. As a result, it was confirmed that the electrical properties and stability were improved by the effect of the double-active layer. [ABSTRACT FROM AUTHOR]

With the goal of preventing abdominal infections after implanting prostheses for hernia repair, polypropylene prostheses were coated with a silver nanoclusters-silica composite (Ag/SiO 2 ) layer, by means of a sputtering process, to confer antibacterial properties. The Ag/SiO 2 coating was deposited, with good uniformity and adhesion, either onto hernia prostheses (CMC) made of two polypropylene layers (macroporous light mesh and thin transparent film), or onto the mesh layer alone. The coating was optimized to achieve a good balance between antibacterial activity and biocompatibility. Antibacterial activity, fibroblast growth on CMC/mesh layer alone, in the presence/absence of Ag/SiO 2 , collagen, and some cytokines involved in inflammation and healing processes, were determined. Preliminary experiments showed that when both layers of CMC were entirely coated, antibacterial properties were achieved while losing prosthesis biocompatibility. Coating the entire CMC was a complex process, thus for subsequent experiments the mesh layer alone was coated, being the antibacterial properties unaffected by this choice and the mesh the part of CMC exposed to possible infection. With a duty cycle of 1 s over 24 on an Ag target, for 15 min deposition time, antibacterial activity, evaluated through the quantitative Colony–Forming Units test, was positive; fibroblasts colonized the coated mesh layer and produced collagen. Cell viability analysis showed that most cells were viable at all experimental times. Moreover, IL-1β and IL-6 decreased, and TGF-β2 increased, in fibroblasts seeded on mesh layer coated with Ag/SiO 2 versus that without Ag/SiO 2 . Ag/SiO 2 -coated mesh layers allowed fibroblast growth and activity, without inducing cell death via apoptosis or necrosis and, at the same time, provided antibacterial activity. [ABSTRACT FROM AUTHOR]

In this report, Bi-doped antimony zinc thin films were prepared on BK7 glass substrates by using direct magnetron co-sputtering technique. Bi was doped at the halfway point of deposition, and the doping contents were 2 at.%, 4 at.%, and 6 at.%, respectively. We present the micro-structural and room-temperature thermoelectric properties of Bi-doped Zn-Sb thin films in this paper. The maximum value of the Seebeck coefficient was found to be 300 μV/K with a Bi content of 6 at.%. This is one of the highest values of the Seebeck coefficient for Zn-Sb thin films deposited by direct magnetron co-sputtering. Carrier concentration is obtained from Hall effect measurements, which provided insights into the transport mechanisms that affected electrical conductivity and Seebeck coefficient. It is significant to doping Bi, which enhances the power factor to an optimal value of 0. 26 mW/mK and the optimal ZT value to 0.086 with the Bi content of 4 at.% at room-temperature. [ABSTRACT FROM AUTHOR]

This work presents the influence of changing Ar:N2 gas ratio on the growth and properties of InAlN films. InAlN films were deposited on -type Si(111) substrates by using magnetron co-sputtering method in 6:12, 10:10, 12:8 and 12:6 Ar:N2 mixtures at 300C. The surface, structural, electrical and optical properties of the deposited films were evaluated at different Ar:N2 ratios. The grain size and film thickness were increased by increasing the Ar flow with respect to N2. Structural characterization by X-ray diffraction (XRD) revealed an improvement in the crystalline quality of the -axis-oriented InAlN film by adjusting the Ar:N2 ratio to 12:8, however no diffraction peak corresponding to InAlN was detected at 6:12 Ar:N2 mixture. The surface roughness of InAlN film exhibited an increasing trend whereas the electrical resistivity of the film was decreased by increasing the Ar:N2 ratio. The bandgap of InAlN film was calculated from the optical reflectance spectra and it was found to change by changing the Ar:N2 gas ratio. The analysis of results from this work shows that the InAlN film with improved physical properties can be obtained through reactive magnetron co-sputtering method by adjusting the Ar:N2mixture to 12:8. [ABSTRACT FROM AUTHOR]

In this work, CuInGa alloy precursor films are fabricated by co-sputtering of CuIn and CuGa targets simultaneously. After selenization in a tube-type rapid thermal annealing system under a Se atmosphere, the Cu(In, Ga)Se (CIGS) absorber layers are obtained. Standard soda lime glass (SLG)/Mo/CIGS/CdS/i-ZnO/ITO/Ag grid structural solar cells are fabricated based on the selenized CIGS absorbers. The influences of selenization temperatures on the composition, crystallinity, and device performances are systematically investigated by x-ray energy dispersive spectroscopy, x-ray diffraction, Raman spectroscopy, and the current density-voltage ( J- V) measurement. It is found that the elemental ratio of Cu/(In + Ga) strongly depends on the selenization temperatures. Because of the appropriate elemental ratio, a 9.92% conversion efficiency is reached for the CIGS absorber selenized at 560°C. After the additional optimization by pre-annealing treatment at 280°C before the selenization, a highest conversion efficiency of 11.19% with a open-circuit ( V ) of 456 mV, a short-circuit ( J ) of 40.357 mA/cm and a fill factor of 60.82% without antireflection coating has been achieved. Above 13% efficiency improvement was achievable. Our experimental findings presented in this work demonstrate that the post-selenization of co-sputtered CuIn and CuGa precursor is a promising way to fabricate high quality CIGS absorbers. [ABSTRACT FROM AUTHOR]

Titanium niobium mixed oxide films have been deposited by reactive magnetron serial co-sputtering. After post annealing at 650 °C in air, a monoclinic TiNb 2 O 7 phase was achieved. Lithium intercalation properties were determined and cathodic switching behavior has been demonstrated for this material. Maximum switching of the integral visual transmittance of 16.8% has been determined for this sample with a thickness of 156 nm. [ABSTRACT FROM AUTHOR]

Exploring highly efficient and robust electrocatalysts to replace the noble metal-based electrocatalysts for alkaline oxygen evolution reaction (OER) is vital and challenging for the conversion of renewable energy. Herein, a novel element incorporation strategy is proposed to synthesize the multi-metallic selenide of (Ni,Fe,Co)Se 2 nanosheets anchored on a stainless steel mesh substrate (NiFeCoSe/SSM). The multi-metallic hybrid film (NiFeCo/SSM) obtained by a co-sputtering method is converted to the (Ni,Fe,Co)Se 2 nanosheets through an alloying-dealloying-selenization process, in which Co and Fe atoms replace part of Ni atoms in the NiSe 2 lattice. The as-obtained NiFeCoSe/SSM displays efficient OER performances in alkaline solutions with an overpotential of 228 mV at 20 mA cm−2 (268 mV at 50 mA cm−2), and a small Tafel slope of 69.8 mV dec−1 in 1.0 M KOH. Furthermore, the NiFeCoSe/SSM electrode demonstrates a remarkable catalytic stability as long as 24.0 h, and its initial nanosheet structure can be well retained after the durability test. Such excellent OER performances of NiFeCoSe/SSM can be attributed to the unique nanosheet structure and the optimized electronic structure due to the synergistic effect among different metallic elements. • A novel element incorporation strategy is proposed to obtain multi-metallic selenide. • Co and Fe atoms replace part of Ni atoms in the NiSe 2 lattice. • The NiFeCoSe/SSM displays efficient OER performances in alkaline solution. • Synergistic effect among metallic elements causes optimized electronic structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zinc tin oxide photoanodes were deposited by commercial co-sputtering process. • Change of ZTO films from amorphous to crystalline was observed at 200 °C. • The highest surface roughness of 7.546 nm for ZTO films was observed at 100 °C. • a-ZTO films with 1000 nm exhibited a high photocurrent response of 0.22 mAcm−2. The process of splitting water into hydrogen (H 2) and oxygen (O 2) gases via the photoelectrochemical (PEC) cell route has recently been emerged as a promising approach, which requires the development of novel and high performance photoanode materials with good stability. Zinc-tin oxide (ZTO) is a promising photoanode material for PEC cell application because of its high chemical stability. Herein, ZTO films were deposited using the commercial co-sputtering process at various substrate temperatures (T sub). At 200 °C of T sub , the ZTO films changed from amorphous to crystalline nature. The ZTO films had the band gap in the range of 3.40–3.70 eV and resistivity in the range of 0.69–0.10 Ω·cm. The high photocurrent of 0.22 mA/cm2 was achieved for the ZTO films sputtered at a T sub of 100 °C and thickness of 1000 nm due to the high surface roughness of 7.55 nm. The electrochemical impedance spectroscopy (EIS) result of ZTO film with 1000 nm thickness showed smallest semicircle, indicating lowest charge transfer resistance. Moreover, a detailed explanation of the effects of the T sub on the properties of films and the performance of photoanode has been presented. [ABSTRACT FROM AUTHOR]

• Microstructure and magnetic properties of films by co-sputtering were investigated. • Fe 3 O 4 was detected at 600 ℃ grown Fe film resulting low magnetic anisotropy. • Micro-height rods were fabricated on an uneven layer at a higher power for Fe. • Films grown at 600 ℃ with 10 and 20 W for fe showed perpendicular magnetic anisotropy. Nanocomposite thin films that exhibit magnetic anisotropy, in which the direction of the easy axis is perpendicular, are highly desirable for emerging spin-based devices. In this study, the growth behavior and magnetic properties of single-layer Fe thin films sputtered at different temperatures were investigated. The surface morphologies of Fe films dramatically changed when the deposition temperature was varied, and the iron oxide phase was detected in a high-temperature-sputtered film, resulting in the degradation of magnetization and magnetic anisotropy. Then, the microstructures and magnetic properties of the co-sputtered Fe-SrTiO 3 nanocomposite thin films were examined. The low-temperate-grown thin films exhibited a flat surface morphology with isotropic magnetic loops at a low power supplied to the Fe target, whereas spherical grains with a strong magnetic anisotropy with in-plane easy axis appeared in a film grown at high power. However, the nanocomposite thin films grown at a high temperature with a higher power for Fe showed perpendicular magnetic anisotropy owing to the vertically aligned Fe rod surrounded by SrTiO 3. The modulation of magnetic anisotropy by tuning the geometry and composition of metal–metal-oxide nanocomposites offers a promising approach for the design of future multifunctional devices. [ABSTRACT FROM AUTHOR]

Aluminum-doped zinc oxide (AZO) is considered as a promising candidate as transparent conductive oxide (TCO) for silicon heterojunction solar cells due to its high carrier density, nontoxic nature, and low cost. Herein, it is presented that the transparency of the AZO film can be optimized through co-sputtering of AZO and molybdenum oxide (MoO x ). Furthermore, aluminum and molybdenum co-doped zinc oxide (MAZO) can be used as both the TCO layer and electron-selective contact (ESC) for silicon heterojunction solar cells. The surface morphology, cation oxidation state, and optical and electrical properties of all MAZO films are characterized. It is found that the transmittance of all MAZO films is significantly increased at a wavelength of 450-800 nm due to MAZO with a stronger Zn-O bond and a wider band gap. The conductivity of MAZO films is approximate to AZO films at a low MoO x target deposit power (50 W), and the sheet resistance of MAZO films increases significantly by increasing the deposition power up to 100 W. Finally, the optimized MAZO films are used as TCO and ESC for silicon heterojunction solar cells, showing a power conversion efficiency of 19.58%. The results show an effective stage to improve the optical properties of AZO through co-doping and the possibility of applying MAZO as a dual-functional layer for silicon solar cells.

We report deposition of pure AlN and Sc x Al 1-x N thin films with different Sc concentration on DLC/Si substrate by RF and DC reactive magnetron co-sputtering method by using Al and Sc as targets. The X-ray diffraction (XRD) results showed that the films have high c-axis-orientation. Electron probe microanalyzer (EPMA) analysis reveals the presence of scandium atoms reduce the space occupied by aluminum atoms, leading to lattice distortion during the phase transition. The SEM cross-section results showed that the Sc x Al 1-x N films are highly aligned along c-axis and have columnar like morphology. The top view of SEM results indicated that the new phase formation above Sc 30.33%, however no new peak appeared in the XRD pattern. The piezoelectric coefficient (d 33 ) of Sc x Al 1-x N thin films are measured and the highest value (11.54 pC/N) is achieved at x = 30.33% increasing 14 times, as that with AlN/DLC/Si, 0.73 pC/N. Sc x Al 1-x N films on DLC/Si substrate have a great potential to be applied on high frequency SAW devices in the future. [ABSTRACT FROM AUTHOR]

In the present work, coatings in the material systems B-C-W and B-C-Ti have been synthesized by pulse magnetron sputtering, to exploit their potential as coatings for hard, wear resistant applications. These layers offer interesting properties, because of the possible amounts of carbides and borides that can form in the non-equilibrium deposition processes. Especially the amount of tungsten in the layers promises high wear resistance and corrosion protection at elevated temperatures. The B-C-W and B-C-Ti thin films have been deposited by pulsed magnetron co-sputtering in bipolar mode, using a boron carbide (B 4 C) target and a metal target (W or Ti) with a maximum total power input of 12.9 W/cm 2 . The amount of metal in the layers has been varied by adjusting the sputtering pulse length of the respective target material. The influence of bias voltage on the properties of B-C-W coatings has been investigated and it was found out that bias voltages of − 60 V … − 100 V lower the hardness of the coatings. The hardness and the Young's modulus of the layers have been determined by nanoindentation. Whereas the majority of coatings exhibits hardness around 20 GPa or lower, maximum hardness of 28 GPa and Young's modulus of 420 GPa are observed in a certain compositional range, in which coatings also distinguish by good thermal stability. Their composition has been analysed by using optical glow discharge emission spectroscopy (GD-OES) and Rutherford backscattering spectrometry (RBS). [ABSTRACT FROM AUTHOR]

Hafnium-aluminum zinc oxide (HAZO) films as an active layer of oxide-transistors with different hafnium (Hf) contents were deposited via co-sputtering of separate targets. The effects of the sputtering power during co-sputtering on the structural, optical, electrical, and chemical properties of the HAZO films were examined. As the sputtering power increased, the structure of the HAZO films changed from polycrystalline to amorphous, and the Hf O bonds in the HAZO films increased, but the Zn O bonds decreased. Also, a bottom-gate-type thin-film transistor (TFT) using the HAZO film as its channel layer was fabricated and characterized. The TFTs using HAZO layer at room temperature as channel layer exhibited the device characteristics, such as a field effect mobility of 0.45 cm 2 /V·s, a threshold voltage of 17.18 V, a subthreshold swing of 0.85 V/decade, an on/off current ratio of 3.68 × 10 7 , and a visible transmittance of 82.7%. It was discovered that the changes of the electrical characteristics of the HAZO TFTs were closely related to the changes of the Zn O/Hf O bonding ratio. [ABSTRACT FROM AUTHOR]

In the present paper, aluminum chromium nitride (Al-Cr-N) films were deposited onto AISI H13 steel substrates by a reactive d.c magnetron co-sputtering system in an atmosphere of Ar/N2 (90/10) gas mixture from a binary target composed of chromium (99.95%) and aluminum (99.99%). Different powers (40, 50, 60, and 70 W) were applied to the target, in order to study the effect of this parameter and the sputtering yield of binary target, on the microstructure and the electrochemical properties of the Al-Cr-N coatings. The corrosion behavior in 3.5 wt. (%) NaCl solution was investigated by electrochemical corrosion tests (Tafel polarization curves and Electrochemical Impedance Spectroscopy (EIS)), and the chemical composition, microstructure and the absorption bands by means of Energy Dispersive X-ray Spectroscopy (EDX), X-ray diffractometry (XRD) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. EIS results showed that the Al-Cr-N coating deposited at 40 W, exhibited the lower porosity and the highest polarization resistance, and subsequently, when the power applied to the binary target increased, the corrosion rate and the porosity increase.