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This dissertation explores epitaxial growth and modifications to the electronic band structure of topological semimetal materials through heteroepitaxy, biaxial strain, and reduced dimensionality. High-quality thin films are grown via molecular beam epitaxy (MBE) and studied using a combination of angle-resolved photoemission spectroscopy (ARPES), density functional theory (DFT), and low-temperature magnetotransport.Recent predictions of topological phases and observations of extremely large magnetoresistance in the class of rare-earth monopnictides, and specifically GdSb, have opened up a new research front aimed at studying the interplay between magnetoresistance, topology, and magnetic ordering. The first part of the dissertation focuses on magnetoresistance and band topology evolution in lattice-matched and biaxially strained GdSb (001) thin films. Lattice-matched GdSb films show a mobility and carrier concentration imbalance, deviating from the commonly assumed compensated charge carrier densities seen in bulk rare-earth monopnictides. Next, we established a clear connection between biaxial strain in GdSb films and the affected band dispersions based on their orbital composition. As biaxial strain is tuned from tensile to compressive strain, the gap between the hole and the electron bands dispersed along [001] decreases.The second part of this dissertation reports the first ARPES investigation conclusively assigning the topological character of bismuth as a trivial ℤ2 state by studying ultrathin Bi (111) films grown on InSb (111)B. Bismuth films hold promise for potential applications in spintronic devices and topological one-dimensional edge transport. Yet synthesizing high-quality, wafer-scale ultrathin bismuth films on non-metallic substrates remains challenging. We achieved large-area Bi (111) films with a single epitaxial domain orientation and mapped the dispersion of surface states and quantum well states. Strong film-substrate interactions were found to promote epitaxial stabilization of the (111) orientation and lead to inversion symmetry breaking. Our results demonstrate that interfacial bonds prevent the semimetal-to-semiconductor transition predicted for freestanding bismuth layers, highlighting the importance of controlled functionalization and surface passivation in two-dimensional materials.Finally, the growth parameters of biaxially strained LuPtBi films on InSb were explored. The half-Heusler compound LuPtBi belongs to a unique group of superconductors with a topologically nontrivial band structure, and very low carrier densities (

The performance of therapeutic ultrasonic (TUS) devices has a high degree of variability because of the fragility of the equipment (its transducer in particular) and its handling. These facts raise doubts about the effectiveness and safety of treatments employing such devices. Currently there is no simple way to adequately verify the performance of these devices. In our first experiments, we used a thermochromatic test body (typically a cylindrical plate 3.7 cm in diameter and 5.8 mm high) irradiated with therapeutic transducers driven by a standard radiofrequency (RF) generator. Results revealed a linear relationship between the thermal image areas, generated by the transducer's irradiation, and their respective effective radiation areas (ERAs), suggesting a good correlation. With five 3-MHz transducers, our group also observed the linear relationship using commercial TUS RF driving devices. In the present work, we used four 1-MHz transducers with their respective TUS RF driving devices and verified that there is a linear relationship between the thermal images and the ERAs at intensities of 1.0 ± 0.1 and 0.5 ± 0.05 W/cm2. The linear relationship obtained at both intensities confirms the suggestion that these thermochromatic test bodies can be used as the first evaluation of the ERAs and can monitor their changes with use. Moreover, if a previous assessment of the ERA and transducer intensities is performed, it is possible to follow the variation in ERA simply by monitoring the test body thermal stain.

Leakage is always a concern in the interface between the cylinder block and the head. Nowadays, sealing of this interface is almost exclusively achieved by multi-layer steel head gaskets. However, it is not only the gasket's quality that is responsible for perfect sealing. An equally important role is played by the surface topography of the mating surfaces. The top surface of the cylinder block and the bottom surface of the cylinder head are machined by face-milling and present periodic tool marks features. Based on the surface topography measured by high definition metrology, this paper presents a novel sealing analysis method to evaluate the sealing performance of the critical topography region around the combustion chambers. The method consists of three modules: tool paths or channels reconstruction, sealing region segmentation based on channels' directions, and sealing analysis on sealing regions with different channel directions. An engineering case demonstrates the sealing analysis procedures and verifies the effectiveness of the sealing analysis method. The analysis of 12 ring-shaped sealing regions found that channels' directions do have a significant impact on surfaces' sealing properties. Circumferential channels or paths are advantageous for surface sealing, while radial channels are prone to leakage.

Quantification of the composition of binary mixtures in secondary ion mass spectrometry (SIMS) is required in the analyses of technological materials from organic electronics to drug delivery systems. In some instances, it is found that there is a linear dependence between the composition, expressed as a ratio of component volumes, and the secondary ion intensities, expressed as a ratio of intensities of ions from each component. However, this ideal relationship fails in the presence of matrix effects and linearity is observed only over small compositional ranges, particularly in the dilute limits. In this paper, we assess an empirical method, which introduces a power law dependence between the intensity ratio and the volume fraction ratio. A previously published physical model of the organic matrix effect is employed to test the limits of the method and a mixed system of 3,3′-bis(9-carbazolyl) biphenyl and tris(2-phenylpyridinato)iridium (III) is used to demonstrate the method. This paper introduces a two-point calibration, which determines both the exponent in the power law and the sensitivity factor for the conversion of ion intensity ratio into volume fraction ratio. We demonstrate that this provides significantly improved accuracy, compared with a one-point calibration, over a wide compositional range in SIMS quantification and with a weak dependence on matrix effects. Because the method enables the use of clearly identifiable secondary ions for quantitative purposes and mitigates commonly observed matrix effects in organic materials, the two-point calibration method could be of significant benefit to SIMS analysts.

With the progress in nanotechnology, the importance of nanodimensional standards is increasing. Realizing nanodimensional standards requires multiple types of high-precision microscopy techniques. The National Metrology Institute of Japan (NMIJ), one of the research domains in the National Institute of Advanced Industrial Science and Technology (AIST), is developing nanodimensional standards using atomic force, transmission electron, and scanning electron microscopes. The current status of nanodimensional standards in NMIJ is introduced herein.

We propose a novel image analysis framework to automate analysis of X-ray microtomography images of sintering ceramics and glasses, using open-source toolkits and machine learning. Additive manufacturing (AM) of glasses and ceramics usually requires sintering of green bodies. Sintering causes shrinkage, which presents a challenge for controlling the metrology of the final architecture. Therefore, being able to monitor sintering in 3D over time (termed 4D) is important when developing new porous ceramics or glasses. Synchrotron X-ray tomographic imaging allows in situ, real-time capture of the sintering process at both micro and macro scales using a furnace rig, facilitating 4D quantitative analysis of the process. The proposed image analysis framework is capable of tracking and quantifying the densification of glass or ceramic particles within multiple volumes of interest (VOIs) along with structural changes over time using 4D image data. The framework is demonstrated by 4D quantitative analysis of bioactive glass ICIE16 within a 3D-printed scaffold. Here, densification of glass particles within 3 VOIs were tracked and quantified along with diameter change of struts and interstrut pore size over the 3D image series, delivering new insights on the sintering mechanism of ICIE16 bioactive glass particles in both micro and macro scales

We report the results of a bilateral comparison of radiation temperature measurements between SASO-NMCC (National Measurement and Calibration Center of Kingdom of Saudi Arabia) and TUBITAK-UME (National Metrology Institute of Turkey) over the range of the nominal target temperature from − 20 to 1600 °C. Two radiation thermometers, employed as the transfer standard instruments, were provided by the pilot laboratory TUBITAK–UME and traceable to the UME primary level radiation temperature scale approximation and realization. During the measurements each laboratory applied its own internal calibration procedures. The results of the comparison showed that all twelve pairs of temperature measurements performed by the participating laboratories are in a good agreement within declared combined standard uncertainty values. The comparison results obtained here support calibration and measurement capabilities both of UME and SASO.

Pulsed laser-based micro-texturing induces topographical and chemical modifications on surfaces that yield beneficial properties such as anti-microbial effect, micro-hydrodynamic bearing, and surface hardening. These properties find a multitude of applications in surface treatment and tribology. However, laser texturing of free form surfaces is a cost and effort-intensive process, specifically medical implants or ergonomically designed tools/devices. Such components often require numerically controlled 3 or 5 axes machines and sophisticated computer-aided manufacturing (CAM) software for precise tool movement. In this manuscript, the authors have designed, fabricated, and validated a jerk-free, cost-effective Stewart platform that works in tandem with an existing laser machining setup. A microcontroller and stepper motor based linear actuators were used to orient and translate the six degrees-of-freedom (DoF) platform. A customized computer program helped maneuver the workpieces (medical implants) for the micro texturing of the 3D surface profiles. As laser irradiation demands a time-invariant focal length for effective ablation, the platform maintains the focal length from the galvo-scanner of the laser machine to the workpiece while maneuvering the workpiece throughout the texture trajectory. To estimate the smoothness of the platform during motion, vibrational parameters were also measured and analyzed. Such cost-effective platforms may find applications in free form texturing in non-contact mode of machining as well as in metrology. Texturing was performed successfully on implants freeform surface with an average diameter of ~35–40 μm and depth of ~15–20 μm.

In this work, we report on the fabrication and characterization of a miniature GaN chip with a size of $1.1\times 1.1\times0.21$ mm3 for surface roughness measurement. Unlike conventional optical metrology that requires external components for the optical coupling between light source and detector, a monolithic GaN-on-sapphire chip fabricated through wafer-scale processes provides light emission and photodetection functions and is capable of sensing a range of average surface roughness from 0.025 to $1.6~\mu \text{m}$ . The sensing performances are compared with fiber-optic metrology, and the ability to real-time monitor the roughness of the moving surface is demonstrated. The novel chip offers the advantage of non-contact and non-destructive, compact structure, simple operation, and in situ measurement capability, which is highly valuable for various practical and industrial surface metrology applications.

The reliable operation of flexible display devices poses a significant engineering challenge regarding the metrology of high barriers against water vapor. No reliable results have been reported in the range of 10–6 g∙(m2∙d)−1, and there is no standard ultra-barrier for calibration. To detect trace amount of water vapor permeation through an ultra-barrier with extremely high sensitivity and a greatly reduced test period, a predictive instrument was developed by integrating permeation models into high-sensitivity mass spectrometry measurement based on dynamic accumulation, detection, and evacuation of the permeant. Detection reliability was ensured by means of calibration using a standard polymer sample. After calibration, the lower detection limit for water vapor permeation is in the range of 10–7 g∙(m2∙d)−1, which satisfies the ultra-barrier requirement. Predictive permeation models were developed and evaluated using experimental data so that the steady-state permeation rate can be forecasted from non-steady-state results, thus enabling effective measurement of ultra-barrier permeation within a significantly shorter test period.

The double crystal diffraction structure based on Bragg diffraction is the core component of the monochromator that is widely used in synchrotron radiation beam lines and monochromatic X-ray radiation devices. The stability of monochromatic X-rays produced by using the T-structure double crystal monochromator at National Institute of Metrology was investigated experimentally. Due to its structural defects, the X-ray flux of the T-structured double crystal monochromator shows poor long-term stability. Inspired by the Channel-cut monochromator structure, we designed a new double crystal monochromator structure to improve the long-term stability of the X-ray flux. Experiments showed that the stability of the monochromatic X-ray flux for the new double crystal monochromator structure was better than 1.0%@1 h, and the energy region and flux rate of the monochromatic X-rays are significantly improved. This work provides a stable and reliable monochromatic X-ray source for the calibration of X/γ detectors such as satellite load detectors, which will contribute to the development of X/γ detection technology.

—The results of developments of materials and structures used for generation and detection of terahertz radiation having applied photoconductive antennas are presented. The developments were carried out in three directions: optimization of parameters of nanoplasmonic antennas, formation of superlattice heterostructures based on InGaAs, and use of layered and two-dimensional semiconductors. The necessity and ways for further improvement in characteristics of the terahertz antennas for expanding the field of application of this radiation in spectroscopy of materials, biomedical diagnostics, metrology, spintronics, wireless communications, etc., are shown.

Mechanical flexibility and deformability are at the core of the advantages offered by organic semiconductors. Therefore, an in-depth understanding of the mechanical properties of these materials is crucial to the design of robust organic electronic devices such as solar cells, sensors, and displays. Since these devices are typically fabricated as thin films, on the order of 200 nm, it can be difficult to measure the mechanical properties using traditional techniques, such as tensile testing, that require bulk samples. This thesis examines and compares various methods of testing the mechanical properties of thin films and correlates the molecular structure of organic semiconductors to such properties. Chapter 1 and Appendix A use mechanical buckling and crack-onset strain techniques to measure the elastic modulus and the strain at fracture in fullerene-based semiconductors. These methods were used to examine the effect of incompletely separated grades of electron acceptors on the mechanical deformability of organic solar cells in an effort to simultaneously improve the mechanical robustness of the organic solar cells and reduce the energy of production. Chapter 2 and Appendix B use mechanical buckling, crack-onset strain, and the onset of wrinkles (collectively known as film-on-elastomer techniques) to show a decrease in the stiffness and an increase in the ductility of small-molecule semiconductors that bear side-chains in the backbone structure and compare the results to fullerene-based semiconductors. Chapter 3 and Appendix C compare the results from two different methods of measuring thin-film mechanical properties; film-on-elastomer and film-on-water methods. The film-on-water method uses water to support thin films while conducting a tensile test. These methods were used to measure the mechanical properties of poly(3-hexylthiophene) in a range of molecular weight and the results were directly compared. In Chapter 4 and Appendix D a technique known as scratch testing was used, for the first time, to measure the cohesion and adhesion of semiconducting polymers. The cohesive and adhesive strength were measured as a function of the length of the side chain in poly(3-alkylthiophenes) and molecular weight in poly(3-hexylthiophene).

We report the development of a high-temperature Seebeck coefficient Standard Reference Material (SRM) for use in instrument validation and interlaboratory data comparison in the temperature range of 295–900 K to support the research, development, and production of materials and devices related to thermoelectric-based energy conversion applications. We describe the synthesis, anneal–quench procedure, and physical characterization of a p-type boron-doped polycrystalline silicon–germanium alloy with a nominal composition of Si80Ge20. For the certification measurements, we describe the measurement protocols, statistical analysis, the certified Seebeck coefficient values, comprehensive uncertainty budgets, and metrological traceability. Our extensive efforts to identify, reduce, and quantify measurement uncertainties will be emphasized. This new SRM complements SRM 3451 Low-Temperature Seebeck Coefficient Standard (10–390 K) to provide certified reference materials traceable to the International System of Units (SI) for Seebeck coefficient measurements within the temperature range 10–900 K.

We study the problem of insufficiently detailed description of the requirements imposed by the state system for guaranteeing the uniformity of measurements in the Russian Federation on the developed and certified measurement methods used for the mechanical testing of various materials. We emphasize the urgency of the problem of compatibility of the requirements imposed on the metrological support of the results of quantitative chemical analyses and indirect results of mechanical testing for the wear resistance of materials in the process of their friction against fixed abrasives. To guarantee the accuracy of measurements of the characteristics of wear resistance of studied materials, we propose to use the grain size of the abrasive material and the frequency of rotation of the abrasive disc as variable factors. In order to establish the requirements to the metrological characteristics of the procedures of mechanical testing, in particular, in finding the relative wear resistance of materials, we justified the conditions required for precision measurements. We also present the results of multistage experiments aimed at testing materials for wear resistance performed with the use of various investigated and consumable materials, measuring instruments, and testing equipment. We also propose and justify the conditions of planning experiments in the case of determination of the other relative mechanical characteristics of the studied materials with an aim to establish precision indicators in the development of methods of mechanical testing for abrasive wear. The application of the accumulated results would enable the developers of the methods for mechanical testing to establish the metrological characteristics of materials in agreement with all requirements of the State System for Ensuring the Uniformity of Measurements of the Russian Federation.

Spectral photometry is currently widely used for quantitative and qualitative analysis of biological molecules in medical biology. The method is based on the ability of molecules to absorb electromagnetic radiation. Modern clinical laboratory diagnostics extensively uses optical methods of analysis that rely on these physical properties of semitransparent objects, such as blood components. Knowing the absorption spectra of blood and its components, it is possible to quantify the concentration of all the components by solving the mathematical system of equations corresponding to these spectra. However, the existing methods of optical analysis of erythrocytes do not allow quantifying their geometric parameters, which may also indicate certain diagnostic signs and be used to analyze the clinical condition of the patient's body. The aim of this work is to evaluate the metrological characteristics of the newly developed method of determining the geometric parameters of erythrocytes, which combines spectral analysis and double annealing. The input data for the 3D imaging of erythrocytes were taken from the images of the sample both made in natural light and illuminated by a coherent light source with different wavelengths. The latter, after some additional image correlation, increases the reliability of the result. The calculation results on the errors and the measuring channel resolution of the digital interference microscope indicate an acceptable accuracy of the method. The accuracy of the three-dimensional image obtained by the proposed method is more than 20% higher than that of other known methods. This allows determining the informative geometric parameters of the structure of erythrocytes more accurately and using them to obtain additional clinical diagnostic characteristics of the patient's body.

The electrode drying process is a crucial step in the manufacturing of lithium-ion batteries and can significantly affect the performance of an electrode once stacked in a cell. High drying rates may induce binder migration, which is largely governed by the temperature. Additionally, elevated drying rates will result in a heterogeneous distribution of the soluble and dispersed binder throughout the electrode, potentially accumulating at the surface. The optimized drying rate during the electrode manufacturing process will promote balanced homogeneous binder distribution throughout the electrode film; however, there is a need to develop more informative in situ metrologies to better understand the dynamics of the drying process. Here, ultrasound acoustic-based techniques were developed as an in situ tool to study the electrode drying process using NMC622-based cathodes and graphite-based anodes. The drying dynamic evolution for cathodes dried at 40 and 60 °C and anodes dried at 60 °C were investigated, with the attenuation of the reflective acoustic signals used to indicate the evolution of the physical properties of the electrode-coating film. The drying-induced acoustic signal shifts were discussed critically and correlated to the reported three-stage drying mechanism, offering a new mode for investigating the dynamic drying process. Ultrasound acoustic-based measurements have been successfully shown to be a novel in situ metrology to acquire dynamic drying profiles of lithium-ion battery electrodes. The findings would potentially fulfil the research gaps between acquiring dynamic data continuously for a drying mechanism study and the existing research metrology, as most of the published drying mechanism research studies are based on simulated drying processes. It shows great potential for further development and understanding of the drying process to achieve a more controllable electrode manufacturing process.

In this paper, we propose an acoustic block for widening the bandwidth and modulating center frequency of airborne transducers to improve the ultrasound imaging or metrology system. When acoustic block is attached, the characteristics of the ultrasonic transducer are changed by the squeeze film effect. Extra elastic and damping force are generated by squeeze film damping and can be changed according to parameters of acoustic block. For impedance matching, a CMUT vibrating in bending mode was used. The CMUT’s FBW is 3.18 % and the center frequency is 103.5 kHz. We changed the area ratio of the acoustic block and attached it to the CMUT. The FBW was changed to 7.14 to 9.14 % and the center frequency to 108.7 to 112.1 kHz. With acoustic block, conventional transducers can be transformed into transducers with better performance in areas such as non-destructive testing and ultrasonic imaging.

The article presents the results of studies of the surfaces of parts processed by the contactless method of laser polishing. The results of technological surface treatment using a laser technological complex based on an ytterbium fibre laser with a power of 5 kW are presented. The results of studies of the surface roughness of the samples after laser treatment, including the non-uniform character due to the redistribution of the liquid metal melt over the surface, are shown. Requirements for metrological support of additive technology have been developed using the example of the process of laser remelting in order to improve quality and further automation.

A new type of graphene-based quantum Hall standards is tested for electrical quantum metrology applications at alternating current (ac) and direct current (dc). The devices are functionalized with Cr(CO)(3) to control the charge carrier density and have branched Hall contacts based on NbTiN superconducting material. The work is an in-depth study about the characteristic capacitances and related losses in the ac regime of the devices and about their performance during precision resistance measurements at dc and ac.

Micelles are self-assembled aggregates that are formed, in many different structures, from surfactants and have a wide range of applications. The critical micelle concentration (CMC) is the concentration of surfactant above which the micelle formation becomes appreciable. This paper reviews techniques that measure the CMC during the formation of micelles involving metal nanoparticles (NPs) with an emphasis on silver NPs. Specifically this review collects and compares such techniques in terms of their advantages and disadvantages. In doing that, this review identifies the useful experimental data on the CMC that each technique yields, but also points out the limitations of each technique. Furthermore, the authors propose an in situ method by using contact angle determination on a substrate/system to measure the CMC in real time. Thus, the goal of this review is to provide a comprehensive list of the most commonly used techniques for the CMC measurement so that future researchers may make informed decisions on what method(s) to use to best meet their needs.

The TIR100-2 emissometer (manufactured by Inglas GmbH & Co.KG) is an emissivity measurement device used by several producers of thermal insulation products for buildings and by some organizations certifying performance of insulation products. A comparison of emissivity measurements on low-emissivity foils involving different measurement techniques, including the TIR100-2 emissometer, gave widely dispersed results; the discrepancies were not explained. The metrological performance of the TIR100-2 emissometer and the uncertainties for measurement on reflective foils was not known, which could be detrimental to users. In order to quantify the performance of TIR100-2 devices for measurement of total near-normal emissivity of low-emissivity foils, the Laboratoire National de Métrologie et d'Essais (LNE) analyzed in detail the measuring principle and listed the associated assumptions and uncertainty sources. A TIR100-2 emissometer actually measures the reflectance and, for opaque materials, the emissivity is calculated from the measured reflectance. The parameters analyzed experimentally are the temperature stability and uniformity of the thermal radiation source, the emissivity of the radiation source, the response function linearity and the spectral sensitivity of the radiometric detection system measuring the reflected radiation, the size of the measurement area, and the measurement repeatability and reproducibility. A detailed uncertainty budget was established. The uncertainty sources taken into account are the uncertainties of the emissivities of the two calibrated standards used for calibration, the stability and uniformity of the radiation source temperature, the non-linearity and the spectral sensitivity of the radiometric detection system, the specific measurement condition related to the radiation source temperature, the uncertainties related to the temperatures of the standards and the sample, the noises on results, and the non-homogeneity in emissivity of the tested material. The combined measurement uncertainty was calculated for different types of reflective foils; the expanded uncertainty is around 0.03 for total near-normal emissivity measurements on smooth low-emissivity foils. A measurement campaign on five types of low-emissivity foils, involving four TIR100-2 emissometers, and a comparison to a primary reference setup at the Physikalisch-Technische Bundesanstalt (PTB) confirmed the uncertainties assessed.

The article presents methods for analyzing the natural gas composition and describes the advantages of Raman spectroscopy compared with gas chromatography. The metrological characteristics of a Raman gas analyzer developed at the Institute of Monitoring of Climatic and Ecological Systems have been studied. A series of measurements of the characteristics of three natural gas simulators with different concentrations of components of gas mixtures were performed. Raman gas analyzers provided high measurement accuracy, close to gas chromatographs when analyzing components with a low molar fraction (0.001–0.010%). Notably, when analyzing components with a molar fraction range of 0.01–100.00%, the accuracy of the proposed Raman gas analyzer surpassed the accuracy of gas chromatographs.

Differential Hall Effect Metrology (DHEM) technique was used to study dopant activation in n-Si and p-SiGe materials. n-type Si samples were prepared by P ion implantation followed by RTA at temperatures ranging from 750ºC to 950ºC. Junction depth and dopant activation through the layers were correlated with process parameters. Using DHEM mobility profiles, a correlation was also established between the EOR defect location and their elimination through high temperature annealing. DHEM resistivity depth profile displayed increased resistivity in the surface region of B-doped SiGe (50%) epi layer. This electrical behavior is in excellent agreement with expected reduction in B incorporation as strain-relaxation occurs towards the free surface. These results demonstrate prime importance of DHEM capabilities for engineering of advanced contacts.

This paper describes experiments concerned with pulse train generation from initially modulated cw light in an anomalous dispersion decreasing fibre. We have obtained stable contrast trains of subpicosecond pulses with a repetition rate in the range 100 – 300 GHz and demonstrated generation of an optical comb spectrum with a –20-dB width of up to 80 nm. A method has been proposed for reconstructing an unknown dispersion profile of a longitudinally nonuniform fibre by comparing experimental data and numerical simulation results.

Sensing via analyte passage through a constricted aperture is a powerful and robust technology which is being utilized broadly, from DNA sequencing to single virus and cell characterization. Micro- and nanoscale structures typically translocate a constricted aperture, or pore, using electrophoretic force. In the present work, we explore the advances in metrology which can be achieved through rapid directional switching of hydrodynamic forces. Interestingly, multipass measurements of microscale and nanoscale structures achieve cell discrimination. We explore this cell-discrimination phenomenon as well as other features of hydrodynamic focusing such as dynamic trapping and discrete interval sensing.

Accurate and precise measurement with authentic data dispersion can be considered as a prime tool to realize any technologies at large scale. In the context of thermoelectric technology, a combination of Seebeck coefficient (α), electrical conductivity (σ) and thermal conductivity (κ) are prominent physical parameters that dictate the performance of thermoelectric materials. In this review article, we have stressed the attention on accurate and precise measurement of Seebeck coefficient that includes various sources of errors from contact geometry, sensors, measurement techniques and thermocouple. In addition to this, the solution of minimizing the errors associated in Seebeck measurement has also been elaborated.

Industrial X-ray computed tomography (XCT) is a tool for non-destructive testing and a volumetric analysis method with the ability to measure dimensions and geometry inside a component without destroying it. However, XCT is a relatively young technology in the field of dimensional metrology and thus faces several challenges. The achievement of a high measurement resolution, which is re-quired to detect small geometrical features, depends on a variety of influencing factors. In this arti-cle, the interface structural resolution (ISR) as one of the key challenges will be investigated. The two-sphere standard called the hourglass standard allows the determination of the structural resolu-tion by evaluation of the surrounding area of an ideal point contact of two spheres after the CT re-construction in form of a neck-shaped transition. Close to the contact point of the two spheres two opposing surfaces exist. Their distances from each other increase as the distance from the contact point of the two spheres increase. The determination of the distances between the spheres’ surface allows a statement about the ISR. A new developed specimen or standard with a variable gap size consisting of calibrated parallel gauge blocks allows statements about the ISR, too. Because of the higher number of probing points of the gauge block standard the results of the determined ISR are more stable compared to the hourglass standard. This paper compares the results of the computed tomography measurements for the designed interface structural resolution standard with those of the hourglass standard.

The increase in applications of the atomic force microscope (AFM) in industrial metrology has contributed to its increased automation. However, automatic replacement of the AFM tip without constraining the instrument's capabilities is still an important challenge. Here, in this article, we propose a system for automated replacement of the AFM tip that is compatible with all imaging modalities and requires minimal modification of a conventional AFM. The proposed strategy employs a wax microsphere as an adhesive for attaching a tip to a tip-less AFM probe and to subsequently detach it. A laser-based heating system and a visual servo control system, which includes an in-house developed out-of-plane motion measurement strategy, are employed for fast and accurate tip-replacement. The system is fabricated, calibrated, and automated tip-replacement is demonstrated with a tip positioning accuracy better than 0.3 μm and an average tip-replacement time of 10 s. Automated replacement of a deteriorated tip has been demonstrated in two specific cases, one in the context of repeated imaging, and another in the context of nanoindentation.

Magnetoelectric multiferroics are solid-state materials which exhibit a coupling between ferroelectric and magnetic orders. This phenomenon is known as the magnetoelectric (ME) effect. Multiferroic materials possess a wide range of potential applications in such fields as metrology, electronics, energy harvesting & conversion, and medicine. Multiferroic research is facing two main challenges. Firstly, scientists are continuously trying to obtain a material with sufficiently strong, room-temperature ME coupling that would enable its commercial application. Secondly, the measurement techniques used in multiferroic research are often problematic to implement in a laboratory setting and fail to yield reproducible results. The aim of the present work is to discuss three most commonly used methods in multiferroic studies; the lock-in technique, the Sawyer-Tower (S-T) circuit and dielectric constant measurements. The paper opens with a general description of multiferroics which is followed by mathematical representation of the ME effect. The main body deals with the description of the aforementioned measurement techniques. The article closes with a conclusion and outlook for future research.

To simplify complex optical systems, a next-generation optical component which combines a refractive element and a diffractive element is desirable. To fabricate these next-generation optical components, it is desirable to keep the focal point of the lithographic lens focused on the curved surface. Keeping the focus constant is challenging for a laser process, as well as for measuring and metrology systems. In this study, a coaxial confocal microscopic type commercialized displacement sensor was used to make it easier to fabricate the pattern required for diffractive optical elements (DOEs) on a curved surface, using direct laser lithography. The test results confirmed that a constant line width of 5 μm could be fabricated on a curved surface such as a cylinder and convex lens using the proposed auto-surface tracking system, with a position error of 1 μm. The diffraction pattern fabricated on the curved surface was analyzed for optical performance and compared with mathematical modeling.

Inverse problem of Mueller polarimetry is defined as a determination of geometrical features of the metrological structures (i.e. 1D diffraction gratings) from its experimental Mueller polarimetric signature. This nonlinear problem was considered as an optimization problem in a multi-parametric space using the least square criterion and the Levenberg–Marquardt algorithm. We demonstrated that solving optimization problem with the experimental Mueller matrix spectra taken in conical diffraction configuration helps finding a global minimum and results in smaller variance values of reconstructed dimensions of the grating profile.

Three-dimensional (3D) complementary metal–oxide–semiconductor (CMOS) integration could enable device scaling beyond the limits of conventional 2D CMOS technology. Such integration requires vertical electrical connections that pass through silicon substrates and interconnect stacked chips. The fabrication of these through-silicon vias (TSVs) creates new challenges in metrology, including the characterization of the thin isolation film deposited on the sidewalls of the TSVs and thickness characterization for wafer thinning. Here, we show that laser-induced terahertz emission microscopy can be used to characterize TSVs. Terahertz emission is observed through the excitation of a transient electric dipole in the depletion field of the TSV using femtosecond laser pulses. The detected terahertz waveform provides information about the local depletion field and thus structural information about the isolation film. By performing a time-of-flight measurement of the terahertz pulse, we can also extract the silicon wafer thickness. Laser-induced terahertz emission, and time-of-flight measurements of the terahertz pulse, can be used to non-invasively characterize through-silicon vias, which are required for three-dimensional CMOS integration.

Methods and means of measurement of the characteristics of the porosity and permeability of solid substances and fabricated materials that are incorporated into GET 210-2019, the State Primary Standard of the units of specific adsorption of gases, specific surface area, specific volume, and dimension of pores, open porosity, and coefficient of gas permeability of solid substances and fabricated materials, are described. A comparison between the metrological characteristics of GET 210-2014 and GET 210-2019 is carried out. The basic means of transmission of the units of quantities that characterize the porosity and permeability of solid substances, such as calibration specimens of approved types based on the micro, meso-, and macroporosity of solid substances, are considered. The results of international comparisons are presented, measurement and calibration capacities are confirmed, and a comparison of the metrological characteristics of GET 210-2019 with the standards of other countries is performed.

A 50 N dead-weight type force standard machine (DWM) was developed by the National Metrology Institute of Japan to expand the lower end of calibration force from 10 N to 1 N. The weights of the DWM consisted of a loading frame and a linkage-weight stack. The loading frame applied a gravitational force of 1 N to a force transducer under calibration. The calibration and measurement capability of the 50 N DWM was verified to be 2 × 10−5 relative using a tuning-fork type force transducer in accordance with ISO 376. The equivalence between the 50 N and 500 N DWMs was confirmed by performing an intralaboratory comparison using the tuning-fork type force transducer. Moreover, the competence of the transducer for the evaluation of DWMs was demonstrated.

Lattice structures can be highly complex imitating natural cellular materials. By the wide adoption of additive manufacturing technologies, lattice structures are a popular design element with many advantages for lightweight and highly functional parts. A detailed examination and an intense inspection of this type of new design element and this new production method is necessary to enable a broad industrialization. In this study we demonstrate how to use x-ray based industrial CT to measure lattice structures in additive manufacturing. This paper shows certain challenges and approaches for metrology on lattice structures. The results show significant deviations between designed and built parts, highlighting the need for quantification and non-destructive inspection.

The analysis of methods and means of experimental determination of the ratio of free and bound moisture in materials is carried out, and it is shown that most of the available measuring instruments do not allow investigating the ratio of free and bound moisture on representative samples of heterogeneous materials, therefore there is a need to create a specialized device for these purposes. Thus, the concerned work is aimed to the development of the differential scanning calorimetry method for studying the state of liquids in inhomogeneous materials and the creation of a cryogenic calorimetric system for the implementation of this method. On the basis of the performed analysis, recommendations were formulated for the development of a measuring system that is capable of examining representative samples of heterogeneous materials of various structures without the need for their preliminary grinding. The method of differential scanning calorimetry has been improved for studying the state of water and organic liquids in inhomogeneous materials in a wide temperature range, which is based on the use of a three-cell differential measurement scheme, as well as the use of cells, the configuration of which allows taking into account the peculiarities of inhomogeneous raw materials. A prototype of a cryogenic calorimetric system has been created, and a method for studying the metrological characteristics of such a system has been developed. On the basis of experimental studies, it has been established that the limits of the permissible relative measurement error of using the developed cryogenic calorimetric system are ± 5%, which corresponds to world analogues.

Fuel cell polarisation performance is typically reported under controlled/constant temperature conditions, as a sign of robust metrology. However, in practice, fuel cells self-heat as they generate current; which varies the temperature across the polarisation curve and affects performance. More detail regarding the internal cell operation can be gleaned by current and temperature distribution mapping. For the case of an unheated cell, ‘self-heating’ increases the cell temperature and improves performance, resulting in a ‘voltage recovery’ and a more homogeneous current and water distribution. For actively heated cells, a reduced current is observed in regions of high temperature and low humidity. The positioning of the gas manifolds also has a decisive impact on performance by affecting the reactant concentration, humidity and water distribution. Counter- and cross-flow orientations in a self-heating cell were studied, with a counter-flow orientation with air flowing with gravity producing the most uniform temperature distribution.

An integrated hardware–software approach was proposed to record the analytical response of sensor matrices exposed for a long time to liquid hydrocarbons and their vapors. A cell was designed and 3D-printed to detect hydrocarbons by photonic-crystal sensor matrices with computer recording and accumulation of the diffuse reflectance spectra with subsequent metrological signal processing. The low content of volatile organic compounds in the air of the working area was determined, and the obtained data agree well with the stages of the working cycle in paint and varnish production. The statistical significance of the changes in the analytical signal of the photonic-crystal sensor that were caused by the time variation of the concentration of hydrocarbons was confirmed.

This article describes a method for comparing the metrological properties of air-cored and solid-cored coils designed as eddy current probes. The approach suggested in this article assumes that a pair of equivalent parameters of an ideal filamentary coil can be assigned to any contact coil so that the impedance variations in both coils are identical. These two parameters include the coil radius and its distance from the surface of a test piece. The experiments performed demonstrate that for equivalent parameters defined in such a way, impedance variations in a real and filamentary coil are the same for a broad frequency range of excitation current and conductivity of the material being tested. Therefore, comparisons between parameters of eddy current probes such as sensitivity, depth of penetration, or inspection coverage can be made with the use of a simple model of an ideal filamentary coil defined by only two parameters. The solution proposed in this article substantially simplifies the calibration process of the measuring instrument, the adjustment and optimization of parameters for newly designed probes, and the development of efficient and reliable mechanisms to eliminate undesired effects (e.g., lift-off).

A rotary laser optoelectronic measurement system is used as part of a multistation network for large-scale metrology. The line-structured laser surface of the transmitter is regarded as an ideal plane for the intersecting measurement. This article presents how the rotary laser surface model can be optimized for large-scale optoelectronic measurement systems. Initially, the deformation of the laser surface caused by the assembly error in a cylindrical lens is analyzed by Zemax simulation and studied by a visual evaluation method based on a high-precision triaxis rotary table. Based on the analysis result, the folded linear surface model and the quadric surface model are applied to reestablish the laser surface model, respectively, to reduce the shape error. A high-precision 3-D coordinate field is designed to acquire an accurate surface parametric model and validate the fitness of the new models. The experimental results based on workshop measurement positioning system (wMPS) show that both optimization models are conducive to improving the fitting accuracy of laser surfaces, and the quadric surface model fits better when the surface shape is closer to the commonest two-folded linear model. Finally, optimizing the laser surface model plays an important role in improving the system measurement accuracy.

The quantification of the sulphur mass fraction in pure copper and copper alloys by GDMS and LA-ICP-MS revealed a lack of traceability mainly due to a lack of suitable certified reference materials for calibrating the instruments. Within this study GDMS and LA-ICP-MS were applied as routine analytical tools to quantify sulphur in copper samples by applying reference materials as calibrators, which were characterized for their sulphur mass fraction by IDMS beforehand. Different external calibration strategies were applied including a matrix cross type calibration. Both techniques with all calibration strategies were validated by using certified reference materials (others than those used for calibration) and good agreement with the reference values was achieved except for the matrix cross type calibration, for which the agreement was slightly worse. All measurement results were accompanied by an uncertainty statement. For GDMS, the relative expanded (k = 2) measurement uncertainty ranged from 3% to 7%, while for LA-ICP-MS it ranged from 11% to 33% when applying matrix-matched calibration in the sulphur mass fraction range between 25 mg kg−1 and 1300 mg kg−1. For cross-type calibration the relative expanded (k = 2) measurement uncertainty need to be increased to at least 12% for GDMS and to at least 54% for LA-ICP-MS to yield metrological compatibility with the reference values. The so obtained measurement results are traceable to the international system of units (SI) via IDMS reference values, which is clearly illustrated by the unbroken chain of calibrations in the metrological traceability scheme.

This research is about the boiler grade samples FWTPET process with SA 213, SA 387 grades in life of a backrest using metrological fits. A recent implementation of hole drilled on the tube's neck and mounted onto the tube plate in this research work. The set of nine experimental runs was tabled as per experimental investigation design. Whereas the study was expanded by using non-traditional genetic methodology to assess the welding joint's feasibility. Furthermore, the stiffness has been calculated and described by graph plots using different input parameters.

Pressure wave therapy is widespread for multiple purposes, from cell metabolism stimulation to tendons, ligaments, muscles, and bones pathologies treatment. However, in the literature, there are no quantitative metrological data related to pressure wave devices. On the contrary, it would be extremely important to have more information on the provided therapeutic signal, which could also be exploited as input for a finite-element model able to foresee the pressure wave propagation inside the tissues. The authors investigated three different versions of the same device in terms of force applied to the tissue. The results show high variability of the pulses intensities (up to 25%), highlighting a nonuniformity of the treatment (in particular at low frequencies and high compressed air pressure). Moreover, the dependence from different parameters (i.e., pulse frequency, pressure, opening time of the solenoid valve for the compressed air pushing the bullet) was investigated. It was found that the lower the frequency and the higher the opening time of the valve, the higher the force applied to the tissue. An estimation of energy density was done; sometimes the limit values provided by pressure wave therapy guidelines (i.e., DIGEST and ISMST) are exceeded, in particular for soft tissues.

To establish the RF power traceability up to 50 GHz in Mexico by means of a primary standard for microwave power and millimeter-wave power, a new coaxial microcalorimeter system in 2.4-mm line size along with thermoelectric-type transfer standards (TSs) were developed and their metrological characterization was performed. Coaxial microcalorimeters allow both broadband operation and power substitution through its feeding line; however, characterization and fabrication of millimeter-wave coaxial lines are technologically difficult. Thus, the design of the microcalorimeter is described, as well as the RF performance of its adiabatic lines. To overcome the lack of coaxial TSs up to 50 GHz, commercially available 2.4-mm thermoelectric power sensors are investigated to use them as low-frequency (LF) power substitution detectors. The effective efficiency is measured in the microcalorimeter by means of calorimetric measurements and the substitution of LF power; the developed measurement procedure is presented as well as the measurement results and the uncertainty analysis. The theoretical basis for the procedure employed to determine the microcalorimeter correction factor, based on the use of specially constructed open and short standards, is described with the measurement results and uncertainties are shown as well. To avoid the drift of the millimeter-wave power during the calorimetric measurements, a novel software leveling loop method for thermoelectric power sensors was devised. This method allows to keep the RF power level variations less than 100 ppm and being a straightforward solution to recent complex hardware realizations.