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In response to the steadily worsening impact of global warming, greater efforts are being made to achieve carbon neutrality. Toyota Motor Corporation developed an in-vehicle solar charging system that utilizes generated solar energy to drive the vehicle. While the ignition is off, energy generated from a solar panel is used to charge the main battery. Then, while the ignition is on, this energy is supplied to the 12 V system to reduce consumption of the main battery energy, thereby helping to improve the electric driving range. This 1st-generation solar charging system adopted in the Prius PHV in 2017 was the first mass-produced in-vehicle solar charging system in the world. In 2022, the 2nd-generation solar charging system was developed and adopted in the bZ4X, including performance improvements such as a newly designed solar roof and lightweight charging system. However, further enhancements are necessary to facilitate the adoption of in-vehicle solar charging systems, as well as to help achieve carbon neutrality. Therefore, the 2nd-generation solar charging system has been adopted on the new Prius Prime and launched in the USA for the first time in 2023. Eight representative cities in the USA were selected under the Köppen climate classification, and the annual and monthly energy generated from its solar panels was calculated from solar radiation data. As a result, the performance of the 2nd-generation solar charging system was calculated in the USA and found to show high product value. This paper introduces the development of the 2nd-generation solar charging system and the performance generated from its solar panels in the USA.

Local distribution of orientation relationship between austenite and martensite is quantitatively examined using lath martensite in an ultra-low-carbon steel. Orientation relationship is systematically deviated between near Greninger–Troiano and Nishiyama–Wasserman orientation relationships around variant boundaries of the smallest misorientation pair, which is observed as the most frequent variant pair in the steel. Misorientation between this variant pair is decreased at some boundaries of the pair. Formation mechanism of the pair is discussed using the observed boundary characters.

The reverse transformation of austenite from pearlite was observed in-situ by using a sophisticated EBSD system. Quantitative information on the nucleation sites and orientation selection of the austenite was obtained. Initially, the nucleation sites were restricted to high-angle grain boundary (HAB) and all the austenite orientations were selected by Kurdjumov-Sachs (K-S) orientation relationship. Latterly, the constraints were relaxed as new nucleation sites were involved. The γ growth was preferentially into the pearlite grains without K-S relation. Nucleation and growth at HAB edge may contribute to γ coarse grains, whereas nucleation at pre-existing γ boundary is important to grain refinement of γ structure.

For any quantitative study on microstructure of a product phase, information on the parent orientation and orientation relationship is essential, yet it is often lost after phase transformation. Even a numerical approach to the problem was proposed elsewhere, a description of the method used for numerical fitting, its efficiency and accuracy has not been reported so far. Here, we address in details the use of Newton's method as one of the fastest convergence techniques for least squares fitting of parent orientation and orientation relationship from EBSD data of the product phase. A robust algorithm with high precision is proposed in a form convenient for programming. Calculation errors, which are evaluated by a novel approach based on simulation of the daughter orientations, are 0.02° for parent orientation and 0.06° for orientation relationship.

The lath martensite structure contains hierarchical substructures, such as blocks, packets and prior austenite grains. Generally, high-angle grain boundaries in the lath martensite structure, i.e. block boundaries, are correlated to mechanical properties. On the other hand, low-angle grain boundaries play an important role in morphological development. However, it is difficult to understand their nature because of the difficulty associated with the characterization of the complex morphologies by two-dimensional techniques. This study aims to identify the morphologies of low-angle boundaries in ultra-low carbon lath martensite. A serial-sectioning method and electron backscatter diffraction analysis are utilized to reconstruct three-dimensional objects and analyse their grain boundaries. A packet comprizes two low-angle grain boundaries - sub-block and fine packet boundaries. Sub-blocks exhibit porous morphology, with two large sub-blocks predominantly occupying a block. Several fine packets with different habit planes from the surrounding regions are observed. Fine packets are present in blocks, which frequently share a close-packed direction with the neighbouring fine packets. In addition, fine packets are in contact with the sub-block boundaries.

In the present study, the average γ/ α′ orientation relationship (OR) was quantified for three series of carbon and low alloy steels. The OR of given steel can be calculated from electron backscatter diffraction (EBSD) data of martensite inherited from one prior-austenite grain. This OR is virtually independent on both prior-austenite grain size and quenching rate. The OR is characterized by small deviation θ 1 between (111) γ & (011) α′ and θ 2 between . Dissolution of C as interstitial impurity causes decrease of θ 1 and non-uniform variation of θ 2 . Addition of Mn or Ni as substitutional impurities up to 3 mass% mainly causes increase of θ 1 . For the same amount of dissolution, Mn shows slightly stronger effect on θ 1 than Ni.

Identification of martensite and bainite in the ferrous alloys is difficult because both morphologies contain similar complex microstructures. Recently, it was pointed out that the frequencies of block boundaries in the morphologies are different from each other. In the present study, a simple method for identifying martensite and bainite using the profile of block boundaries is suggested. This method was applied for upper and lower bainites and lath martensite in Fe–0.6mass%C alloy. The lower bainite can be separated by the ratio of 52 degrees / α’ boundaries. Furthermore lath martensite and upper bainite are identified using near twin block boundaries and block boundary density.

The present study aims to clarify the development of blocks and packets in lath martensite in Fe–18Ni maraging steel using three-dimensional observations. The specimens were step-quenched in order to clarify the sequential development of the three-dimensional morphology in a prior austenite grain. In a prior austenite grain, we found that five independent packets formed during the early stage of martensitic transformation. Four of the packets exist along the prior austenite grain boundaries and one packet grows from the boundary edge into the prior austenite grain. Each packet consists of a single block, although the fraction of martensitic transformation is 50.6%. The observed rules of the block-selection are as follows: (1) the blocks have near Kurdjumov–Sachs orientation relationship with adjacent austenite grains and elongated directions of the laths are parallel to adjacent grain boundaries and (2) transformation shear directions of the laths are parallel to adjacent grain boundaries.

Two Japanese swords produced by 70 years ago and 600 years ago were investigated. Four-point bending test has been performed to estimate the strength of sharp edge of Japanese sword for the first time. The strength of sharp edge with fine lath martensite microstructure was evaluated, taking the specimen geometry of bending test into consideration. The strength of modern sword is estimated as high as approximately 4500 MPa (by four point bend test) and is considered to be a great value along with high hardness, which is comparable with the value of high performance tool steels. The fracture surface showed that the crack propagation behavior is smooth around sharp edge and ductile like the zigzag morphology from wavy pattern region into the core region.

Japanese sword are understood that they contain martensite and could not be produced without tamahagane steel by tatara process. A newly produced sword (short sword) prepared from tamahagane steel using traditional forge-folding ( tatara ) method was examined by optical microscopy and SEM/EBSD method for observing the microstructural features in it. It was found that the microstructure of the sword was martensite with lath type morphology. The feature of lath martensite was characterized by observing the prior austenite grain, packet and block boundaries with respect to their linearity and curviness. Thus a new method of comparison between tatara steel and ordinary Fe–C steel was mentioned by measuring the curved line and the straight line contained in the boundaries corresponding to the prior austenite grains, packets and blocks.

In this study we have evaluated the energetic stability of boundaries between Kurdjumov–Sachs (K–S) variants to explain the morphology of sub-block and block in lath martensite. Interfacial energy of different variant pairs was calculated by using molecular dynamics simulation. Three dimensional models of tilt and twist boundary with a method evaluating interfacial energy were developed. The results showed energetic stability of twist boundary with small misorientation from 0 to 5.5°/[0 1 1] α′ in consistence with previous transmission electron microscope observation. For other boundary with larger misorientation, the twin-related variants had the smallest interfacial energy although this variant pair was not frequently observed in electron backscatter diffraction analysis.

Lath martensite is an important structure in steels; however, its quantitative volume fractions have not been measured to date. In this study, we seek to clarify the morphologies and volume fractions of the structural units of lath martensite-packets and blocks—by using three-dimensional observations with local crystallographical analyses. Lath martensite structures in ultra-low carbon and high-carbon steels contain both coarse and small packets, whose threshold of volume fraction in prior austenite grain is 10%. The volume fractions of the coarse packets in prior austenite grain in the specimens are greater than 70%, although the number of packets is fewer than five. In ultra-low carbon steel, the coarse packets have flat packet boundaries and contain three types of blocks with a plate-like morphology. On the other hand, in high carbon steel the morphology of the coarse packets is sponge-like and contains six types of blocks. There are more small packets than coarse packets in the observed specimens, and the volume fraction of the small packets is lower. The number of small packets in high carbon martensite is more than that in the ultra-low carbon martensite. Volume measurements show a distribution of volume fractions of Kurdjumov–Sachs (K–S) variants. In high carbon martensite, all the K–S variants appear continuously. The volume fractions of some K–S variants are relatively low in ultra-low carbon martensite.

The effect of titanium carbide (TiC) on morphology of low-carbon steel martensite was studied by means of electron backscatter diffraction (EBSD). The nucleation and growth of new morphology subunits such as packet, block and sub-block are observed in the area surrounding of micron-sized TiC particles. The misorientation from a fitted orientation relationship between martensite and austenite near TiC particle is larger than the average misorientation with a localized characteristic. The position of new morphology subunits has a well correspondence with the area in vicinity of TiC particle, which has large misorientation. The micron-sized TiC particle plays a role of stress concentrator in austenite during martensitic transformation which suppresses growth of one martensite variant while stimulates nucleation and growth of another one.

Japanese sword has finer grain size and lath martensite in the microstructure of sharp edge amazingly. Nowadays these structures are considered to be one of the ideal structure at which are greatly aimed to strengthen or improve toughness of steels. Though the carbon content of its sharp edge is 0.70 mass %, there are no lenticular martensite and no micocracking in that area. As a result of bending test by actual sword specimen, one sword was finally bent, the other sword was broken. However it is found the sharp edge in Japanese sword has such a large bending strength 2500, 4600MPa respectively as modern, high performance tool steels and the difference of crack propagation under bending depends on the microstructure distribution and the grain size in cross section of Japanese sword.

Microstructures of a nickel/austenitic-steel (AISI304) interface, which has been bonded through in-situ cold-rolling of clean surfaces (pre-sputtered by argon ion) within a vacuum apparatus (~10–3 Pa), then followed by an annealing at 500°C, are investigated by transmission electron microscopy. We frequently find significant traces of thin oxide layers of 5–10 nm in thickness, which commonly reveal complex microstructures composed of bi-layers of different types of oxides. Origin of such interface oxides is presumably due to a slight oxygen contamination of the sputtered-surface in the present moderate vacuum condition, and the oxide precipitation at the bonded-interface has been promoted during annealing. Concerning that the strength of the present Ni/steel cold-rolled interface remarkably increases during an early stage of the annealing at 500°C, it is concluded that their strong interface bonding is supported both by nanometeric oxide-layers as well as direct metal/metal contacts.

The microstructure evolution at interfaces of a layer-integrated steel sheet artificially constructed by ductile austenitic stainless (SUS304) and high-strength martensitic (SCM415) steel layers, which were bonded through a cold-rolling and a subsequent annealing at 1000°C, has been investigated using scanning transmission electron microscopy (STEM) combined with energy dispersive X-ray spectroscopy (EDS). We find that a significant microstructural reconstruction around the SUS304/SCM415 interface has been accomplished during a short-time annealing followed by water-quenching; the resultant microstructures are found to consist of recrystallized austenite and lath martensite grains for the SUS304 and SCM415 layers, respectively. Interestingly, the original SUS304/SCM415 interface appears to migrate and extend into the SUS304 side, an occurrence of which can be reasonably explained by the martensitic transformation across the composition-gradient interface during quenching. These microstructural evolutions fairly account for a microscopic mechanism on how hetero-interface bonding can be achieved via simple cold-rolling/annealing procedures.

There is increasing demand for oxide-dispersion-strengthened ferritic alloys that possess both high-temperature strength and irradiation resistance. Improvement of the high-temperature properties requires an understanding of the operative deformation mechanisms. In this study, the microstructures and creep properties of the oxide-dispersion-strengthened alloy 14YWT have been evaluated as a function of annealing at 1000 °C for 1 hour up to 32 days. The ultra-fine initial grain size (approx. 100 nm) is stable after the shortest annealing time, and even after subsequent creep at 800 °C. Longer annealing periods lead to anomalous grain growth that is further enhanced following creep. Remarkably, the minimum creep rate is relatively insensitive to this dramatic grain-coarsening. The creep strength is attributed to highly stable, Ti-rich nanoclusters that appear to pin the initial primary grains, and present strong obstacles to dislocation motion in the large, anomalously grown grains.

The development of porosity at 1000 °C in an oxide dispersion-strengthened ferritic alloy containing nanoscale (∼2–4 nm) oxide particles is investigated. A comparison with an alloy fabricated by internal oxidation instead of mechanical alloying demonstrates that the porosity formation is associated with mechanical alloying of the alloy powder with Y 2 O 3 in argon. The pores grow in spite of a submicron grain size suggesting that the grain boundaries are not effective paths for removing entrapped gas from the pores.

A MoSi2 coating was successfully formed on a Mo-9Si-18B alloy, consisting of Mo5SiB2 (T2) and Mo solid solution (Moss) phases, using pack cementation with Si. Isothermal and cyclic oxidation tests of pack-cemented Mo-9Si-18B alloys were performed at 1300 °C and 1500 °C. Steady-state oxidation rates at both temperatures are almost equal to those of pure MoSi2. The MoSi2 layer is completely transformed into Mo5Si3 (T1) containing B after oxidation at 1500 °C for 24 hours. Thermal expansion of the T1 phase is anisotropic, but a [001] texture in the growth direction for the columnar grains in the T1 layer reduces thermal stresses generated around the phases. Evolution of T1 layers during oxidation between 1300 °C and 1500 °C was investigated; their growth rate constants and the interdiffusion coefficient of Mo and Si in the Mo-Si-B system have been evaluated and compared with those in the binary Mo-Si system. Furthermore, we have studied phase transformations in a simpler system MoSi2vs T2 using MoSi2/T2 diffusion couples. Layers of T1 and MoB + T1 were formed in the diffusion zone during oxidation at temperatures between 1400 °C and 1600 °C. This behavior is different from that of the pack-cemented Mo-9Si-18B alloy. Pack-cemented T2 single crystals show a diffusion structure similar to that of MoSi2/T2 diffusion couples, but the ratio of layer thickness is different. Based on these diffusion results, a method for extending the lifetime of the MoSi2 layer is proposed.

Single crystals of (Mo0.8Nb0.2)5Si3, (Mo0.85W0.15)5Si3 and Mo5Si3 were grown and their thermal expansion along the a- and c-axes and single crystalline elastic property were investigated. An anisotropy ratio of coefficient of thermal expansion (ac/aa) is lower for (Mo0.8Nb0.2)5Si3, and higher for (Mo0.85W0.15)5Si3 at RT than that for Mo5Si3. However, the ac/aa for (Mo0.8Nb0.2)5Si3 increases with increasing temperature and the ac/aa of the three compounds is similar at 800°C. The values of isotropic average Young’s (E), bulk (K) and shear (G) moduli for (Mo0.8Nb0.2)5Si3 is the lowest and those for (Mo0.85W0.15)5Si3 is the highest in the three compounds. On the other hand, the difference of E between [100] and [001] increases when partial substitution of Mo by Nb occurs and it decreases when partial substitution of Mo by W occurs. Simply compared with the results of thermal expansion anisotropy, the result shows opposite tendency.

To establish quantitative basis for oxidation-protective coating of Mo–Si–B ternary alloys by MoSi2, phase transformations in MoSi2 vs. Mo5SiB2 diffusion couples have been studied. Two layers are formed on reaction diffusion at temperatures between 1400 and 1600 °C: a single-phase layer of Mo5Si3 and a two-phase layer consisting of Mo5Si3 and MoB. The growth obeys the parabolic low for both the layers, and the rate constants of the two layers are found to be approximately equal. The interdiffusion coefficient in the T1 layer has also been evaluated. The microstructural evolution in the diffusion zone is modeled in terms of mass conservation, as well as that of a Mo–9Si–18B two-phase alloy coated with MoSi2 reported previously [Intermetallics 12 (2004) 407].

The directional thermal expansion and elastic properties of Mo5Si3, (Mo0.8Nb0.2)5Si3, and (Mo0.85W0.15)5Si3 have been studied as a function of temperature through the use of single crystals. Thermal expansion anisotropy was reduced by Nb and W alloying. The decrease in thermal expansion anisotropy by Nb alloying was only found to occur at low temperatures, and thermal expansion anisotropy of (Mo0.8Nb0.2)5Si3 was similar to that for the other two compounds at 800 °C. Values for the polycrystalline Young’s, bulk, and shear moduli calculated from the measured single-crystal elastic constants are reduced by Nb alloying, and increased by W alloying at all temperatures studied. The elastic modulus E was calculated for the orientations between [100]-[001] and [100]-[010]. In contrast to the effects of Nb on thermal expansion anisotropy, Nb alloying increased the E[001]/E[100] elastic anisotropy.

The T 2 phase in the Mo–Si–B system has great potential for ultra-high temperature structural applications. We examined creep of the single crystalline and polycrystalline T 2 phase. The steady-state creep rate of the [021] oriented specimens is as low as 3.1×10 −8 s −1 at 1500 °C and 432 MPa. The minimum creep rates at 1500 °C of the [001] oriented and polycrystalline specimens are 6.9×10 −8 s −1 at 600 MPa and 3.0×10 −8 s −1 at 300 MPa, respectively. The activation energy for creep was found to be ∼740 and ∼400 kJ mol −1 for [021] and [001] oriented specimens, respectively. Stress exponent for creep was found to be 6.8, 4.3 and 4.6 for [021] and [001] oriented and polycrystalline specimens, respectively. Creep resistance of the single crystalline and polycrystalline T 2 specimens is much better than that of MoSi 2 and Si 3 N 4 base structural ceramics.

Following an investigation of the oxidation behavior of a two-phase Mo-9Si-18B alloy coated with MoSi2, which was prepared by pack-cementation with Si (Intermetallics 2003, 11:763), we have studied the kinetics of the evolution of the MoSi2 layer during cementation and the formation of Mo5Si3 layer during high-temperature oxidation, in order to provide quantitative basis for the surface-coating procedure and the protection performance. The microstructures of the surface layers have also been examined. The growth of MoSi2 on Mo-9Si-18B during pack-cementation at 900 °C obeys the parabolic time law and the rate constant is close to the estimate from the literature data of Mo/Si reaction diffusion. The growth must occur by inward lattice diffusion of Si into MoSi2. The as-prepared MoSi2 coating layer consists of fine grains of the order of about 500 nm, with a [001] texture in the growth direction. The growth constant of Mo5Si3 developed between MoSi2 and the matrix during annealing in air at temperatures between 1300 and 1500 °C is significantly lower than those reported for the binary Mo-Si system, but the integrated interdiffusion coefficient is approximately equal. The activation energy for the growth (about 220 kJ/mol) is lower than in the binary system, while the activation energy of interdiffusion (240 kJ/mol) is not very different. The layer of Mo5Si3 consists of columnar grains with a [001] texture in the growth direction, which might have formed to reduce the thermal stresses arising from its anisotripic thermal expansion during cyclic oxidation.

High purity single crystals of Mo5SiB2(D8l), Mo5Si3(D8m), Mo5Si3C(D88) and Ti5Si3(D88) and polycrystals of Nb5SiB2(D8l) and V5SiB2(D8l) have been grown and their electrical and thermal properties have been measured. The resistivity of all transition metal 5-3 silicides exhibit a negative curvature with a tendency towards saturation when it is plotted as a function of temperature. The resistivity of Mo5SiB2, Mo5Si3 and Mo5Si3C is saturated at a lower value than that of Ti5Si3, Nb5SiB2 and V5SiB2. In Mo5Si3C where room temperature resistivity is large because of large residual resistivity, resistivity saturation is pronounced and results in almost temperature independent resistivity. Thermal conductivities for Mo5SiB2, Mo5Si3, Mo5Si3C and Ti5Si3 are about 27, 19, 8.5 and 11 W/mK, respectively. Mo5Si3C exhibits almost temperature independent thermoelectric power along [11 2 0]. On the other hand, thermoelectric power of Mo5Si3C along [0001] and Mo5SiB2 decreases monotonically with increasing temperature.

Multiphase Mo–Si–B alloys are potential candidates for ultra-high temperature application. The T2/Moss and (Mo,Nb)ss/T1/T2 eutectic alloys have been grown using an optical floating zone method. In this paper, their microstructure, fracture toughness at room temperature and strength at high temperatures are investigated.

High purity single crystals of the Mo5Si3C phase with the D88 type structure have been grown and their physical and mechanical properties have been measured. The composition of single crystals is Mo4.66Si3.00C0.402. Lattice constants of the compound are a=0.7286 nm and c=0.5046 nm. Vickers micro-hardness and fracture toughness are 13.4 MPa and 1.3 MPa m1/2, respectively. The anisotropy ratio of thermal expansion coefficient (αc/αa) of the compound is approximately 2 at 773 K. In contrast, the elastic properties for the compound are nearly isotropic. The deformation behavior of the compound has been studied in compression using [0001], [13 4 0], [22 4 9] oriented single crystals. These single crystals can be deformed plastically at temperatures higher than 1573 K. Slip occurs on {0001} 2 0> and an unidentified non-basal system.

This paper presents a low-power and compact passive supply-resonance (SR) suppression filter. By using an on-chip waveform monitor, a power-delivery network (PDN) impedance including package, and board PDNs is in-situ analyzed to identify the SR frequency f SR . A notch filter which consists of coupled bonding-wire coils and an on-chip MOS capacitor bank is auto-tuned for the SR suppression. This passive filtering approach reduces the power loss to 1/5∼1/10 and the static power to effectively zero as compared to an active SR suppression circuit [1]. The coupled bonding-wire coil enhances its self-inductance and hence shrinks the on-chip capacitor size for the layout-area saving. A 0.18μm CMOS test chip demonstrates SR suppression by >43% with only

Tolerance to morphine analgesia was determined daily by exposing rats either to the same box or to different boxes by a repeated administration of morphine (5 mg/kg). In the Acquisition Phase, the rats received either morphine or saline in the same or different boxes for four consecutive days, and the process of tolerance development was assessed by a hot-plate test. Marked tolerance developed in the group exposed to the same contextual cue, whereas tolerance was attenuated in the group exposed to different cues. In the Extinction Phase, all rats received saline injections in the box exposed on Day 1 for four days. On the first day, hyperalgesia was observed only in the rats injected with morphine in the same contextual cue. In the Retest Phase, the rats underwent a second morphine injection and to some extent showed recovery from tolerance. In the Acquisition Phase, the number of animals showing abnormal activity with morphine injection increased monotonically in the group that was administered morphine in the same box (Group M-S) before injection, but in the group administered the drug in different boxes (Group M-D), no systematic development of the activity occurred. These results indicate that the hindering of a rat's ability to associate with environmental cues under the effect of morphine slows the development of tolerance, and the withdrawal and anticipatory symptoms, and the tolerance of morphine involves psychological and pharmacological factors.

Mo5X3+α (X=Si, B, C) intermetallic compounds such as Mo5SiB2 (D8l), Mo5Si3 (D8m) and Mo5Si3C (D88) have a great potential for ultra-high temperature applications. The present study was undertaken putting greater emphasis on clarifying how their physical and mechanical properties are similar or different in terms of a structure type. Some interesting features are summarized in this paper.The resistivity of Mo5SiB2, Mo5Si3 and Mo5Si3C single crystals exhibited a negative curvature (d2ρ(T)/dT25Si3C with large ρ0 due to impurity carbon atoms, resistivity saturation is pronounced. In contrast, a much higher temperature is required to reach saturation in the Mo5SiB2. The anisotropy ratio of CTE (αc/αa) for the Mo5SiB2 is about 1.2–1.6 and is significantly reduced from about 2 of the Mo5Si3 and Mo5Si3C. On the other hand, the Young's modulus of the Mo5SiB2 is more anisotropic than those of the Mo5Si3 and Mo5Si3C. Plastic anisotropy was observed in the Mo5SiB2, because only slip on [001] {100} is operative at 1500°C. On the contrary, plastic deformation was observed at temperatures above 1300°C for the Mo5Si3C and Mo5Si3. Anisotropy of their plastic deformation was much less than that of the Mo5SiB2, presumably because more than two slip systems can be activated. Creep resistance of the Mo5SiB2 is much better than that of the Mo5Si3 as well as the most advanced materials such as MoSi2 and Si3N4 based structural ceramics.

We have investigated zeta potential measurements in order to estimate the polarization of zinc oxide (ZnO) and found that the sign and time dependence of zeta potential for ZnO{0001} wafers depend on their polarity, which is caused by an accumulation and a chemisorption of H+ or OH− counterions. The −c polarity of ZnO films on both Al2O3 and (0001) substrates was confirmed by zeta potential measurements. X-ray diffraction (XRD) and reflection high energy electron diffraction (RHEED) showed that the zeta measurements do not significantly degrade the film structure and surface morphology. These results should allow for the non-destructive determination of polarity at a lower cost and with a more understandable profile than that determined by conventional physical methods.

A dielectric constant of over 100 000, with dielectric loss of less than 0.1, was found in 1.0 mol. % Ni-doped KTaO3 (KT:1%Ni) single crystals, showing temperature and frequency stabilities favorable for capacitor applications. The dielectric constant was found to depend on the electrode material, and Ag electrodes markedly enhanced the dielectric properties. This result indicates that the giant effective dielectric constant is due to a non-Ohmic electrode contact with a semiconducting KT:1%Ni.