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Biospecimen imaging is essential across various fields. In particular, a considerable amount of research has focused on developing pretreatment techniques, ranging from freeze-drying to the use of highly conductive polymers, and on advancements in instrumentation, such as cryogenic electron microscopy. These specialized techniques and equipment have facilitated nanoscale and microscale bioimaging. However, user access to these environments remains limited. This study introduced a novel technique to achieve high conductivity in bioimaging by employing a magnetically controlled sputtering cathode to facilitate low-temperature deposition and low-electron bombardment. This approach allows for the convenient high-magnification observation of highly structured three-dimensional specimens, such as pill bugs and butterfly wings, and fragile specimens, such as single-cell protozoan parasites, using metal deposition only. Furthermore, it is easily accessible in the field of bioimaging because it does not require any pretreatment and enables surface analysis of biospecimens with an electron microscope using only a single pretreatment process. Protozoa, which are microorganisms, were successfully observed at high magnification without structural changes due to thermal denaturation. Furthermore, metallic film deposition and electrochemical signal measurements using these metallic films were achieved in pill bugs. [ABSTRACT FROM AUTHOR]

Hafnium Nitride (HfN) is a promising and very robust alternative to gold for applications of nanoscale metals. Details of the nanomorphology related to variations in strain states and optical properties can be crucial for applications in nanophotonics and plasmon‐assisted chemistry. Ultrafast reciprocal space mapping (URSM) with hard X‐rays is used to unveil the nanomorphology of thin HfN films. Static high‐resolution X‐ray diffraction reveals a twofold composition of the thin films being separated into regions with identical lattice constant and similar out‐of‐plane but hugely different in‐plane coherence lengths. URSM upon femtosecond laser excitation reveals different transient strain dynamics for the two respective Bragg peak components. This unambiguously locates the longer in‐plane coherence length in the first 15 nm of the thin film adjacent to the substrate. The transient shift of the broad diffraction peak displays the strain dynamics of the entire film, implying that the near‐substrate region hosts nanocrystallites with small and large coherence length, whereas the upper part of the film grows in small columnar grains. The results illustrate that URSM is a suitable technique for non‐destructive and depth‐resolved investigations of the morphology of nanostructures. [ABSTRACT FROM AUTHOR]

A temperature measurement system with a reflected laser beam that does not require temperature modulation was developed for the thermal design of electronic devices. The system combines a balanced photodetector and lock-in amplifier to make reflectance change measurements possible with an extremely high signal-to-noise ratio. First, to evaluate the accuracy of the reflectance change measurement, the reflectance change of a Ni thin film temperature-controlled by a heater and thermocouples was measured as a function of temperature change. To evaluate the accuracy of the temperature change measurement, the reflectance change was measured by heating a Ni thin film that imitated the wiring pattern of an electronic circuit. The experimental results showed that the standard deviation of the ratio of reflectance change from the reference reflectance was <1.00 × 10−5 at a constant temperature. Moreover, the error margin of the calculated temperature change was ±1.0% for a change of 22 °C or more from the reference temperature, and the performance was sufficient for the estimation of local temperature. [ABSTRACT FROM AUTHOR]

There is a growing need for precise and rapid detection methods in fields such as biomedical diagnostics, environmental monitoring, and chemical analysis. Surface plasmon resonance (SPR) sensors have been used for the detection and quantification of a wide range of analytes, including biomolecules, chemicals, and gases, in real-time. Despite the promising capabilities of SPR sensors, there remains a gap in creating a balance between having a large enough area to capture a significant number of analytes for detection and being small enough to ensure high sensitivity. This research aims to explore the design of a D-shaped SPR-based optical fiber sensor, focusing on the use of copper, gold, and silver thin films at optimized width and thickness of 10 µm and 45 nm, respectively, to improve the sensor's performance. Employing a computational approach, this study examines the influence of the optimized width and refractive indices of metallic films on the sensor's characteristics. The 10 µm width of the metallic thin film has been found to produce an optimal balance between the sensitivity and the dynamic range of the sensor. Leveraging on the ratio of the real and imaginary parts of the dielectric constant of the thin film metal provides insight into the optical properties and sensitivity at certain wavelengths. Within an analyte refractive index range of 1.37–1.42 and a wavelength range of 650–1200 nm, results indicate that silver outperforms gold and copper at the optimized width with a wavelength sensitivity, and detection accuracy of 12,300 nmRIU−1, and 3.075, respectively. By optimizing the width of the metal thin film at 10 µm, a highly sensitive D-SPR is designed, allowing for enhanced sensor detection capabilities for a wide range of bioanalytes. [ABSTRACT FROM AUTHOR]

Biospecimen imaging is essential across various fields. In particular, a considerable amount of research has focused on developing pretreatment techniques, ranging from freeze-drying to the use of highly conductive polymers, and on advancements in instrumentation, such as cryogenic electron microscopy. These specialized techniques and equipment have facilitated nanoscale and microscale bioimaging. However, user access to these environments remains limited. This study introduced a novel technique to achieve high conductivity in bioimaging by employing a magnetically controlled sputtering cathode to facilitate low-temperature deposition and low-electron bombardment. This approach allows for the convenient high-magnification observation of highly structured three-dimensional specimens, such as pill bugs and butterfly wings, and fragile specimens, such as single-cell protozoan parasites, using metal deposition only. Furthermore, it is easily accessible in the field of bioimaging because it does not require any pretreatment and enables surface analysis of biospecimens with an electron microscope using only a single pretreatment process. Protozoa, which are microorganisms, were successfully observed at high magnification without structural changes due to thermal denaturation. Furthermore, metallic film deposition and electrochemical signal measurements using these metallic films were achieved in pill bugs.

There is a growing need for precise and rapid detection methods in fields such as biomedical diagnostics, environmental monitoring, and chemical analysis. Surface plasmon resonance (SPR) sensors have been used for the detection and quantification of a wide range of analytes, including biomolecules, chemicals, and gases, in real-time. Despite the promising capabilities of SPR sensors, there remains a gap in creating a balance between having a large enough area to capture a significant number of analytes for detection and being small enough to ensure high sensitivity. This research aims to explore the design of a D-shaped SPR-based optical fiber sensor, focusing on the use of copper, gold, and silver thin films at optimized width and thickness of 10 µm and 45 nm, respectively, to improve the sensor’s performance. Employing a computational approach, this study examines the influence of the optimized width and refractive indices of metallic films on the sensor’s characteristics. The 10 µm width of the metallic thin film has been found to produce an optimal balance between the sensitivity and the dynamic range of the sensor. Leveraging on the ratio of the real and imaginary parts of the dielectric constant of the thin film metal provides insight into the optical properties and sensitivity at certain wavelengths. Within an analyte refractive index range of 1.37–1.42 and a wavelength range of 650–1200 nm, results indicate that silver outperforms gold and copper at the optimized width with a wavelength sensitivity, and detection accuracy of 12,300 nmRIU−1, and 3.075, respectively. By optimizing the width of the metal thin film at 10 µm, a highly sensitive D-SPR is designed, allowing for enhanced sensor detection capabilities for a wide range of bioanalytes.

The focused ion beam (FIB) technique using Ga ion beams is generally employed for transmission electron microscopy (TEM) sampling owing to its location-specific beam controllability on materials. However, Ga ion beam bombardment-induced damage hinders reliable structural analysis. Furthermore, Ga ions implanted in the damaged surface layer substantially lower the chemical stability of the samples, such as metal thin films. Here, aiming for atomic-level interface structural analysis, we propose a useful approach for the TEM sample preparation of heteroepitaxial Ag/Cu metal films without physical damage or chemical instabilities using the Xe plasma FIB (PFIB) system. Xe plasma-assisted sampling ensured that the interface structure of the Ag/Cu metal film remained intact; in contrast, the sample prepared using the focused Ga ion beam was damaged by elemental mixing. Furthermore, the sample prepared by Xe plasma milling exhibited robust structural stability over time after exposure to air in contrast to the sample prepared by Ga-ion milling, which induced structural decomposition owing to oxidation. In addition to the static structural analysis, the Cu thin film sample prepared by Xe PFIB exclusively exhibited pristine structural properties under in situ electrical biasing experiments, thus confirming the feasibility of conducting a fundamental study of Cu electromigration without artifacts. • Xe plasma FIB is useful for artifact-free metal film TEM sampling. • Xe plasma FIB preserves intact interface structure without elemental mixing in metal films. • Xe-milled TEM sample has higher oxidation resistance than Ga-milled TEM sample. • Xe-milled TEM sample of metal films is appropriate for in-situ basing experiments. [ABSTRACT FROM AUTHOR]

Hydrophilicity of the aluminium thin film's surface is one of the imperative surface characteristics needed for metal pad bonding process in microelectronic circuitries. In this paper, we present a study on the influence of argon plasma exposure on the surface properties of sputter-deposited aluminium thin film layer. The exposure of aluminium thin film layer in argon plasma at atmospheric pressure and low pressure are carried out and compared. The water contact angle and surface topology of the aluminium's surface are inspected. The aluminium–gold metal–metal ohmic contact resistance and the aluminium thin film sheet resistivity are measured. Argon plasma has modified the originally hydrophobic aluminium's surface into hydrophilic profile, which may be related to its increase of surface energy. Higher/smaller thin film surface roughness has been measured from the low-pressure/atmospheric-pressure argon plasma exposure that produces thin film with higher (9.64 Ω)/smaller (6.78 Ω) contact resistivity compared to the unexposed aluminium thin film layer (7.85 Ω). The argon plasma exposure treatment on the aluminium thin film has generally improved its surface properties, inducing hydrophilicity surface profile for the aluminium metal pad. The conducted treatment at the atmospheric pressure level specifically helps to reduce the surface roughness and increase the thin film layer conductivity. [ABSTRACT FROM AUTHOR]

CeCoIn 5 (Co115) thin films have been grown on Al 2 O 3 (000l) substrates through the pulsed laser deposition (PLD). The films are grown mainly along the c -axis, with CeIn 3 and In-related alloys. The rock-salt type grains are nucleated, where Co115 grains mixed with excess indium are evenly distributed over the substrate. The electrical resistivity of the films shows a Kondo coherence peak near 47 K and the zero-resistance superconducting state at 1.8 K, which is the first observation in the PLD grown thin films of Co115. The Rietveld refinement of the thin films shows that the c / a ratio (tetragonality) is suppressed to 1.6312 from 1.6374 of single crystals, which is consistent with the linear relationship between the superconducting transition temperature and tetragonality. The good agreement indicates that the PLD could provide an alternative route to tune the 2D character of the critical spin fluctuations to understand the superconducting pairing mechanism of Co115. • CeCoIn 5 thin films have been grown on an Al 2 O 3 (000l) substrate via pulsed laser deposition technique. • The films are mainly oriented along the c -axis, and the rock-salt type grains are nucleated and connected grain by grain. • The electrical resistivity shows a Kondo coherence peak near 46 K and the superconducting state at 1.8 K. • The temperature dependence of the upper critical field is in good agreement with that of high-quality single crystals. [ABSTRACT FROM AUTHOR]

• Ag/NiCoSe 2 electrode was constructed successfully by magnetron sputtering. • Ag/NiCoSe 2 –10 shows great improvement over NiCoSe 2 in performance and stability. • The enhancement mainly owes to the Ag layer on the surface of NiCoSe 2 grains. • Excessive Ag deposition would prevent the inner NiCoSe 2 grains from functioning. • This work provides new idea for developing supercapacitor with high reliability. In this work, a binder-free energy-storage electrode material of Ag nanoparticles coated nickel cobalt selenide (NiCoSe 2) on Ni foam (NF) was first proposed. Wherein, NiCoSe 2 was synthesized by one-step hydrothermal method using ascorbic acid as reductant, and the coating of Ag nanoparticles on NiCoSe 2 were performed by magnetron sputtering method. The specific surface area was greatly increased due to the deposited Ag nanoparticles, and in this way the impedance of the electrode decreased, and the electrochemical properties were enhanced. When the magnetron sputtering time is 10 s, Ag/NiCoSe 2 electrode exhibits the most excellent performances. However, further increase of sputtering time may result in the over cover on NiCoSe 2 , with great deterioration in electrochemical behavior. Single NiCoSe 2 electrode possesses an area capacitance of 1600.7 mF cm−2 at a current density of 2 mA cm−2, while Ag/NiCoSe 2 electrode could reach up to 2280 mF cm−2. The asymmetric supercapacitor (ASC) assembled by Ag/NiCoSe 2 and activated carbon (AC) electrodes shows a high energy density of 0.171 mWh cm−2 as well as a power density of 17.340 mW cm−2, and the cyclic stability remains at 90.1% after 4000 cycles, which is superior to 83.7% of the NiCoSe 2 single electrode. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract In parallel with soaring efficiency, interest in multi-functional semitransparent perovskite solar cells (PeSCs) has emerged for special applications such as windows and tandem cells. To demonstrate air-stable as well as efficient ITO-free semitransparent PeSCs, ultra thin Cu and Ni, which are well-known non-precious metals having sufficient electrical conductivity, are investigated as bottom transparent electrode and optimization of devices is systematically carried out. Semitransparent Ni/NiO X based PeSC exhibits the average visible transmittance (AVT) of 22% and power conversion efficiency (PCE) of 8.20%. Considering required AVT for the application of power-generating window of ∼25% and recent reports, this result is one of the best performances reported to date. Highlights • p-i-n structured perovskite solar cells (PeSCs) with thin Cu or Ni transparent electrode are investigated. • To demonstrate air-stable & efficient ITO-free semitransparent PeSCs, optimization of devices is carried out. • Semitransparent PeSCs fabricated on Ni/NiO X exhibits the average visible transmittance (AVT) of 22% and PCE of 8.20%. • Ni/NiO X based device also shows superior stability to Cu based systems. [ABSTRACT FROM AUTHOR]

Highlights • The texture of deposited Al films was found to be changed by amorphous Ge substrates. • The high mobility of Ge atoms during the Al film growth was studied. • EBSD, XPS and AES depth profiling analyses were performed. • The concept of interaction-induced island-growth model was put forward. Abstract The difference in the microstructural and texture evolution of Al films grown on amorphous SiO 2 (a-SiO 2) and amorphous Ge (a-Ge) substrates have been investigated. Surprisingly, the a-Ge substrate was found to change the preferred orientation of Al grains from the conventional (1 1 1) to the unconventional (1 1 0). The effect of the high mobility of Ge atoms at the metal-semiconductor interface on the microstructural and texture evolution of the metal thin film was studied. The diffusion of the Al adatoms on the a-Ge substrate was suppressed owing to the segregation of Ge atoms at the film surface. The mobility of Al grain boundaries was also suppressed because of grain-boundary wetting by the Ge atoms. It is concluded that the a-Ge substrate could tailor the Al grain orientation from (1 1 1) to (1 1 0) owing to the change in the film-growth mode from three-dimensional to two-dimensional nucleation. The concept of interaction-induced island-growth model, which is based on the Volmer–Weber growth model, is also discussed here. This work thus demonstrates how the atomic mobility at the interface of the metal thin film and the semiconductor substrate controls the film microstructure and texture during deposition. [ABSTRACT FROM AUTHOR]

[Display omitted] • Epitaxial growth of NbN thin films using atomic layer deposition. • An in-plane compressive strain in the NbN film grown on MgO substrates. • 50% reduced resistivity owing to an enhanced carrier mobility. • Plausible mechanism in the growth of epitaxial NbN films. The epitaxial growth of NbN thin film was accomplished via atomic layer deposition (ALD) for the first time using NbCl 5 and NH 3 as the Nb precursor and nitrogen source at a deposition temperature of 450 ℃. The cubic NbN thin film was grown epitaxially on a cubic MgO crystal through the coherent lattice matching between NbN and MgO with a small lattice mismatch (∼2.8%). A high concentration of Cl impurity of 4–5% remained in NbN thin films grown on a SiO 2 substrate using ALD. However, the Cl impurity concentration decreased to ∼ 2% in the epitaxially grown NbN thin films, which facilitated the epitaxial growth of NbN thin films on the MgO substrate. The origin was attributed to a residual strain at the NbN/MgO interface, which induced a bond length change in Nb-N-Cl. The bond length change may promote Cl desorption during NbN ALD because an in-plane compressive strain in the NbN film and an in-plane tensile strain in the MgO surface were observed. Finally, the epitaxially grown NbN thin film exhibited a 50% lower resistivity than that grown with a polycrystalline phase based on the enhanced carrier mobility owing to the improved crystallinity of epitaxial NbN thin films. [ABSTRACT FROM AUTHOR]

Abstract Metal thin films are used widely to solve the vibration problem. However, damping mechanism is still not clear, which limits the further improvement of the damping properties for film and the development of multi-functional damping coating. In this paper, Damping microscopic mechanism of porous metal films was investigated at both macroscopically and microscopically mixed levels. Molecular dynamics simulation method was used to model and simulate the loading-unloading numerical experiment on the micro-pore and vacancy model to get the stress-strain curve and the microstructure diagram of different defects. And damping factor was calculated by the stress-strain curve. The results show that dislocations and new vacancies appear in the micro-pores when metal film is stretched. The energetic consumption from the motion of dislocation is the main reason for the damping properties of materials. Micro-mechanism of damping properties is discussed with the results of in-situ experiment. Graphical abstract Image 1 Highlights • Generation of new defects and dislocation friction cause the damping properties. • Increasing temperature has disadvantage of enhancing damping properties. • The motion of dislocation as the main reason for damping properties. • Designing the dislocation structure of the film can improve the damping properties of film. [ABSTRACT FROM AUTHOR]

Transition metal nitride thin films such as TiN are necessary as conducting electrodes in memory and transistor devices. Due to their high work function (> 4.7 eV), NbN thin films have recently attracted attention to replace TiN thin films as capacitor electrodes using atomic layer deposition (ALD) process in dynamic random access memories (DRAMs) to reduce leakage currents in the capacitors. Unfortunately, the NbN ALD process using NbCl 5 and NH 3 as the Nb precursor and nitrogen source resulted in a high resistivity (> 500 μΩ·cm) despite its low bulk resistivity (∼10 μΩ·cm at 300 K) because of the residual Cl impurity (> 5%) within the NbN film. In this study, an alternative ALD surface reaction pathway is proposed by introducing H 2 S gas pulses between the NbCl 5 and NH 3 pulse steps to lower the Cl impurity concentration. Using the alternative ALD reaction, the residual Cl concentration was reduced below 1.5% (decrease by > 50%) at the specific ALD deposition temperature of 673 K. Finally, this reaction produced a greater decrease in the resistivity (> 30%) of NbN thin films than the conventional NbN ALD at 673 K. • Alternative reaction in atomic layer deposition (ALD) for NbN thin film growth. • Introduction of H 2 S in the NbN ALD process using NbCl 5 and NH 3. • Reduction of Cl impurity concentration by using the alternative ALD reaction. • Decrease in the resistivity of the NbN thin films owing to the Cl impurity decrease. [ABSTRACT FROM AUTHOR]

[Display omitted] • Generation of different 2D-LIPSS with circularly polarized light from various metal thin films on silicon. • Influence of thin film thickness, metal, and laser irradiation parameters on surface morphology. • Influence of metals oxidation affinity on pattern formation. • Simultaneous nano-patterning and chemical conversion of Cu. • Simultaneous nano-patterning and alloy formation from stacked thin films. One- and two-dimensional laser-induced periodic surface structure (LIPSS) formation of various metal (Ag, Cu, Fe, Zn, Ti) thin films on silicon wafers is achieved by irradiation with circularly polarized 532 nm nanosecond laser pulses. The occurrence and the evolution of pseudo-1D linear periodic, 2D honeycomb-like structures, and 2D periodic nanoparticle arrays were mapped for each element in dependence on the energy applied, i.e. the effective pulse number, and the metal thin film thickness. Samples series with increasing pulse counts monitor, like snapshots, the progressive pattern evolution. Because the metal thin films are of nanometer thickness only, the co-structuring of the silicon substrate must be taken into account in all cases. Even more complex are LIPSS formations on samples carrying two stacked thin films. The LIPSS formation process of thin films becomes rather complex as soon as co-structuring of the substrate, oxidation of the material, and alloy formation with substrate material or a potential second thin film layer are considered. All these effects affect the morphology of the formed LIPSS patterns. [ABSTRACT FROM AUTHOR]

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report a method to suppress streaming potential using an Ag-coated microfluidic channel on a p-type silicon nanowire (SiNW) array measured by a multiplexed electrical readout. The metal layer sets a constant electrical potential along the microfluidic channel for a given reference electrode voltage regardless of the flow velocity. Without the Ag layer, the magnitude and sign of the surface potential change on the SiNW depends on the flow velocity, width of the microfluidic channel and the device's location inside the microfluidic channel with respect to the reference electrode. Noise analysis of the SiNW array with and without the Ag coating in the fluidic channel shows that noise frequency peaks, resulting from the operation of a piezoelectric micropump, are eliminated using the Ag layer with two reference electrodes located at inlet and outlet. This strategy presents a simple platform to eliminate the streaming potential and can become a powerful tool for nanoscale potentiometric biosensors. [ABSTRACT FROM AUTHOR]

Widespread interest in optical and electrical properties of nanostructured systems began more than 20 years ago. Here, optical and electrical properties of Co/Ni bilayer nanofilms are explored. These optical and electrical properties were described in terms of a common confined wavefunction spanning both Co and Ni layers. The effective relative electron mass parameter f estimated for this bilayer film was about 0.1489. Temperature dependence of the current–voltage characteristics of the Co/Ni bilayer nanofilms was described as that of a Schottky diode with the Schottky barrier height of U S = 24 cm−1, very small compared to other semiconducting materials. Therefore, Co/Ni bilayer nanofilms apparently had semiconducting properties, which may approximately be described using Schottky diode theory. Such semiconducting properties of bilayer metal nanofilms could be used in special low-temperature low-consumption electronic devices. [Display omitted] • UV–Vis absorption spectra of Co/Ni bilayer nanofilms were recorded and analyzed. • Current–voltage (I–V) characteristics of Co/Ni bilayer nanofilm recorded at different temperatures. • I–V characteristics analyzed in terms of 1D quantum confinement for transverse electron motion in a bilayer metal nanofilm. [ABSTRACT FROM AUTHOR]

• • Fatigue crack development of Cu thin film was predicted by deep convolutional neural network. • • Electrical resistance ratio, which is an important indicator of damage, was also predicted. • • The predictions only required easy measurements of microscope observation and electrical resistance. • • More than half of the predicted cracks corresponded with actual microscopic image cracks. • • Electrical resistance ratio was predicted with small average error (6.5%). Metal thin films are used in a wide range of devices. To ensure long-term reliability, damage prediction of the films should be considered. In particular, it is important to perform damage prediction of Cu thin films on flexible circuit boards because of severe fatigue conditions under repetitive, large strains. In this study, the development of multiple, complicated fatigue cracks in Cu thin films was predicted using a deep convolutional neural network (CNN). The CNN was trained to output a microscopic image of the fatigue crack development after 2000 cycles upon receiving a microscopic image of the area prior to crack development as an input. The microscopic images used for training were obtained via an actual fatigue test. In addition, the electrical resistance ratio, which is an important indicator of damage, was predicted by another CNN. The CNN output the electrical resistance ratio upon receiving a microscopic image of fatigue crack development as an input. More than half of the predicted cracks corresponded with actual cracks. Furthermore, the average error of the evaluated electrical resistance ratio was small (6.5%). [ABSTRACT FROM AUTHOR]

Infrared and ultraviolet femtosecond lasers were used for interfering laser processing of thin gold film on silica glass substrate for the fabrication of MHA (metallic hole array) metamaterial devices. Through single shot processing and step scanning, devices with an area of 10 × 10 mm were successfully fabricated. The lattice constant of the device processed at infrared wavelength was 1930 nm, and it was shortened to 760 nm by means of ultraviolet wavelength. The transmission spectrum was observed, and the anomalous transmission peak wavelength was approximately 59% shorter in the case of a 760 nm lattice constant compared with a 1930 nm lattice constant. [ABSTRACT FROM AUTHOR]

Multimode Ti4+-diffused LiNbO3 planar waveguide doped with Sc3+ ions was fabricated by codiffusion of stacked Sc2O3 and Ti-metal thin film coated onto Z-cut congruent LiNbO3 substrate at 1060 °C in wet O2. The Ti4+-concentration was profiled by secondary ion mass spectrometry. The refractive index profile is constructed from measured mode index, and correlated with the Ti4+ profile. Other two related issues including the contribution of Sc3+-doping to substrate refractive index and Li2O out-diffusion were also studied. The results show that the Sc3+-doping has little contribution to the substrate index and the Li2O out-diffusion was effectively suppressed. The index change and Ti 4+-concentration follow an exponential relationship with a power index 0.54/0.79 for the ordinary/extraordinary ray. The relationship is similar to that of conventional Ti:LiNbO3 waveguide because of little contribution of Sc3+-doping to the substrate index and effective suppression for Li2O out-diffusion. Some considerations for fabricating an optical-damage-resistant Ti:Sc:LiNbO3 waveguide are given. [ABSTRACT FROM PUBLISHER]

We report the growth of CeIrIn 5 thin films with different crystal orientations on a MgF 2 (001) substrate using pulsed laser deposition technique. X-ray diffraction analysis showed that the thin films were either mainly a- axis-oriented (TF1) or a combination of a - and c -axis-oriented (TF2). The characteristic features of heavy-fermion superconductors, i.e. Kondo coherence and superconductivity, were clearly observed, where the superconducting transition temperature ( T c ) and Kondo coherence temperature ( T coh ) are 0.58 K and 41 K for TF1 and 0.52 K and 37 K for TF2, respectively. The temperature dependencies of the upper critical field ( H c 2 ) of both thin films and the CeIrIn 5 single crystal revealed a scaling behavior, indicating that the nature of unconventional superconductivity has not been changed in the thin film. The successful synthesis of CeIrIn 5 thin films is expected to open a new avenue for novel quantum phases that may have been difficult to explore in the bulk crystalline samples., (© 2022 IOP Publishing Ltd.)

Abstract: In this paper, we discuss how ion-beam techniques can be used to accurately direct the self-assembly of metallic nanostructures. Fabrication of micrometer-scale three-dimensional cubes (boxes) is demonstrated. The milling by ion-beam locally modifies the thickness of the film and its structures such as grains boundaries, film surface, and film/vacuum interface. The local manipulation can be done according to a design, either at once (parallel), or in a sequence within an electron/ion (SEM/FIB) dual-beam microscope. [Copyright &y& Elsevier]

Abstract: The thermomechanical behavior of gold films caused by ultrashort pulse lasers is investigated using a combined continuum-atomistic approach with the inclusion of the hot electron blast force. During the very early laser-metal interaction, a nonequilibrium thermal state and a significant hot electron blast wave are generated in the films. The laser heating leads to an initial compressive stress with the peak occurring near the irradiated side of the films. For a 100-nm film, a conversion from compression to tension starts in the mid-portion, the resulting tensile stress converts back to compression, and then the above stress conversions repeat. For the thicker films of 500nm and 1μm, the tensile stress starts from the irradiated side due to the free surface stress reflection, and the resulting two-fold shock wave comprising tension and compression propagates towards the rear surface and then reflects back to the front-side. The effect that the thermal stress decreases with increase of the pulse duration is more pronounced in thinner films. Based on the simulated dynamic stress responses, nonthermal damage to the 100-nm film could occur in its mid-depth region while the material could be nonthermally removed from either the front or rear-side of the 500-nm and 1-μm films. [Copyright &y& Elsevier]

Abstract: Metal thin-film patterning is of technological significance because modern electronic devices commonly require an electrode or metallization pattern. There are many cases where this pattern consists of two different metallic layers in order to improve the mechanical and electrical contact. We here show that double-layered metal thin films evaporated on glass can be directly patterned by a spatially-modulated pulsed Nd–YAG laser beam incident from the backside of the substrate. This method utilizes a pulsed laser-induced thermo-elastic force exerting on the film which plays a role to detach it from the substrate. Since the film is polycrystalline with nano-sized grains, a spatially-modulated thermo-elastic force may enable selective removal of the material by shearing along the weakly-bonded grain boundary regions. Many different combinations of Al, Ag, and Au layers have been investigated and their pattern fidelity and morphology are discussed, along with the simulation results for double-layered nanocystalline films. [Copyright &y& Elsevier]