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Amorphous mixed-anion semiconductors (AMASs) such as amorphous zinc oxynitride and amorphous zinc oxysulfide (a-ZnOS) have attracted attention as rare-metal-free amorphous semiconductors that exhibit electron mobility comparable to or greater than the electron mobilities of typical amorphous oxide semiconductors (AOSs), including amorphous In–Ga–Zn–O (a-IGZO). A characteristic feature of AMASs is that their conduction-band minimum (CBM) mainly consists of s-orbitals of the single cation, in contrast to conventional AOSs, whose CBM is composed of s-orbitals of multiple cations. This unique band structure suggests that the potential of carrier electrons in AMASs exhibits less spatial fluctuation than that of carrier electrons in AOSs. In this study, we analyzed the temperature dependence of the electron transport properties of a-ZnOS thin films using the random barrier model to evaluate the potential barrier height and its spatial variation. The analyses revealed that the barrier height of a-ZnOS is comparable to that of a-IGZO. This result was attributed to the large covalent nature of Zn–S bonds strongly influencing the potential at the CBM through the antibonding interaction. [ABSTRACT FROM AUTHOR]

Background: Families raising children with disabilities assume risks to their health and lives. Therefore, it is necessary to support these families to improve family empowerment, which is the ability of these families to control their own lives and to promote the collaborative raising of children with disabilities. This is the first online intervention program focusing on the empowerment of families raising children with disabilities who live at home in Japan. Method: The program consists of four online peer-based group sessions. Moreover, the families engage in several activities in stages wherein they discover their own issues, find measures to resolve them, and take action, while visualizing interfamily relationships, including social resources, and the status of their family life, with facilitators and other peer members. This study is a non-randomized, waitlist-controlled trial. It compares the results of the intervention group (early group) and the waitlist-controlled group (delayed group). The participants are allocated to the early or delayed group in the order of their applications. The main outcome is family empowerment. Other outcomes are the caregiver burden, self-reported capability to use social resources, self-compassion, and the quality of life (QOL) of primary caregivers. The timeline of the online outcome evaluation is as follows: the initial evaluation (Time 1 [T1]) is conducted before the start of the first early group program, and post-intervention evaluation (Time 2 [T2]) is conducted immediately (within 1 week) after the early group completes all four sessions (4 weeks) of the program. Follow-up evaluation (Time 3 [T3]) is conducted 4 weeks after the post-intervention evaluation. This timing is the same in the delayed group, but the delayed group will attend the program after a 4-week waiting period, compared to the early group. Discussion: The intention is to evaluate whether the provision of the program developed in this study and the evaluation test design are feasible and to verify the efficacy of this program. Trial registration: The UMIN Clinical Trials Registry (UMIN000044172), registration date: May 19, 2021. [ABSTRACT FROM AUTHOR]

Micro-LEDs have been attracting attention as a potential candidate for the next generation of display technology. Here we demonstrate the feasibility of large-area monolithic integration of multi-color InGaN micro-LEDs via pulsed sputtering deposition (PSD) and a standard photolithographical technique. The PSD allows for sequential epitaxial growth of blue and green InGaN LED stacks connected with the GaN based tunneling junction. The tunneling junctions serve as protective layers on p-type GaN against the dry etching damage and hole injection layers in each blue and green emission InGaN active layer. The tunneling junction-connected multi-color InGaN LED stack contributes to the high-density and large-area monolithic integration of RGB micro-LEDs using standard photolithography and the ICP-dry etching method. [ABSTRACT FROM AUTHOR]

I EJIHPE i was able to uphold its high standards for published papers due to the outstanding efforts of our reviewers. Thanks to the efforts of our reviewers in 2022, the median time to first decision was 23 days and the median time to publication was 50 days. MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. [Extracted from the article]

Background: Bispectral index (BIS) monitoring is a widely used non-invasive method to monitor the depth of anesthesia. However, in the event of surgeries requiring a frontal approach, placement of the electrode may be impossible at the designated area to achieve a proper BIS measurement. Methods: We developed an investigational interface device to connect needle-electrodes to BIS sensors. The safety and clinical performance were investigated in patients who underwent surgery. Direct BIS values from a disposable BIS electrode and indirect values via the interface device were simultaneously recorded from the same areas of electrode placement in a single patient. The agreement between the direct and indirect BIS values was statistically analyzed. Results: The interface device with a silver electrode demonstrated sufficient electric conduction to transmit electroencephalogram signals. The overall BIS curves were similar to those of direct BIS monitoring. Direct and indirect BIS values from 18 patients were statistically analyzed using a linear mixed model and a significant concordance was confirmed (indirect BIS = 7.0405 + 0.8286 * direct BIS, p<0.0001). Most observed data (2582/2787 data points, 92.64%) had BIS unit differences of 10 or less. Conclusions: The interface device provides an opportunity for intraoperative BIS monitoring of patients, whose clinical situation does not permit the placement of conventional adhesive sensors at the standard location. [ABSTRACT FROM AUTHOR]

Herein, we report the growth method of ultrathin indium nitride (InN) films on aluminum nitride (AlN) templates by sputtering and its application to field-effect transistors (FETs). Although island-like InN surfaces were formed at the initial film growth stage, the height of the islands on the surface could be controlled by changing the growth temperature. The height of the InN islands grown at 500 °C was lower than those grown at 440 °C and 480 °C. To demonstrate an application of the InN/AlN heterostructure to FETs, we fabricated FETs using a 2-nm-thick InN film grown on an AlN template. The FET with the InN channel grown at 500 °C exhibited a drain current density of 0.19 mA/mm and an on/off ratio of approximately 102 although the drain current of the FET with the InN grown at 450 °C was not adequately controlled by the gate bias. These results indicate that the growth condition of InN films is responsible for the characteristics of InN/AlN FETs. [ABSTRACT FROM AUTHOR]

We have characterized highly conductive Si-doped GaN films with a high electron mobility of 112 cm2V−1s−1 at an electron concentration of 2.9 × 1020 cm−3, prepared using pulsed sputtering deposition (PSD). With an increase in the doping concentration, the absorption edge was found to shift toward a higher energy level, owing to the Burstein-Moss effect, thus making this material suitable for the transparent conductive tunneling electrodes of visible and ultraviolet-A light-emitting diodes. The full width at half maximum value of the near-band-edge (NBE) emissions in a photoluminescence spectrum measured at 77 K was as small as 185 meV, even for the sample with the highest electron concentration of 2.9 × 1020 cm−3. Such sharp NBE emissions from PSD-grown heavily Si-doped GaN films can be explained by an analytical model with a low compensation ratio θ of around 0.1, which is consistent with the exceptionally high observed electron mobility. These results indicate the strong potential of the low-temperature PSD growth technique for the formation of high-quality, heavily Si-doped GaN. [ABSTRACT FROM AUTHOR]

We have grown structurally high-quality GaN with a low residual shallow donor concentration (<5 × 1015 cm−3) through pulsed sputtering. Light Si doping to this film with a Si concentration of 2 × 1016 cm−3 leads to the formation of an n-type film with room temperature electron mobility of 1240 cm2V−1s−1, which is comparable to that of the best values for n-type GaN as obtained via conventional growth techniques. At lower temperatures, electron mobility increased, and it reached to 3470 cm2V−1s−1 at 119 K primarily owing to the reduction in the phonon scattering rate. A conventional scattering theory revealed that such high electron mobility in GaN grown via pulsed sputtering can be attributed to the precise control of low-level intentional donors and the reduction in compensating centers. These results are expected to provide significant benefits for future GaN technology by offering high-quality GaN at cost effectively and at low temperatures. [ABSTRACT FROM AUTHOR]

The Si-doped AlN films were grown on sapphire (0001) by pulsed sputtering deposition (PSD), and their structural and electrical properties were investigated. A combination of PSD and high-temperature annealing process enabled the growth of high-quality AlN (0001) epitaxial films on sapphire (0001) substrates with atomically flat stepped and terraced surfaces. The transmission electron microscopy observations revealed that the majority of the threading dislocations in AlN belonged to the mixed- or edge-type, with densities of 2.8 × 108 and 4.4 × 109 cm−2, respectively. The Si-doping of AlN by PSD yielded a clear n-type conductivity with a maximum electron mobility of 44 cm2 V−1 s−1, which was the highest value reported for AlN that was grown on sapphire. These results clearly demonstrated the strong potential of the PSD technique for growing high-quality conductive n-type AlN on sapphire. [ABSTRACT FROM AUTHOR]

Low Temperature grown GaAs (LT-GaAs) was incorporated as a buffer layer for GaAs on Si (GaAs/Si) and striking advantages of this structure were confirmed. The LT-GaAs layer showed high resistivity of 1.7 × 10 ω-cm even on a highly defective GaAs/Si. GaAs/Si with the LT-GaAs buffer layers had smoother surfaces and showed much higher photoluminescence intensities than those without LT-GaAs. Schottky diodes fabricated on GaAs/Si with LT-GaAs showed a drastically reduced leakage current and an improved ideality factor. These results indicate that the LT-GaAs buffer layer is promising for future integrated circuits which utilize GaAs/Si substrates. [ABSTRACT FROM AUTHOR]

Rudists are a group of bizarrely shaped marine bivalves that lived in the Tethys Ocean from the Late Jurassic to the latest Cretaceous. They are morphologically variable, including snail-like, cup-like, and horn-like shapes. In the Middle East, Cretaceous carbonates with rudists and rudist fragments are well exposed in many outcrops as well as oil and gas fields. For rudist-bearing carbonates in the subsurface, knowledge of rudist morphology and mode of occurrence must be derived from observation of drillcores; however, understanding the three-dimensional (3D) geometry of rudists from observation of core surfaces is difficult. In paleontological studies of rudists, X-ray computerized tomography (CT) scans have been carried out to reconstruct the inside texture of rudist shells for the purpose of taxonomic research. In contrast, in the oil and gas industry, application of X-ray CT scanning technology is generally focused on direct measurement of reservoir properties. Studies of rudist fossils within drillcores by means of X-ray CT have not yet been conducted. We have developed a new protocol to observe core interiors using X-ray CT. We obtained high-resolution 3D images of rudists in a drillcore by means of surface rendering, volume rendering, and 3D printing. X-ray CT and 3D modeling is a novel method for non-destructive analyses of the morphology and mode of occurrence of fossils within drillcores. [ABSTRACT FROM AUTHOR]

Stable carbon (δ13C) and oxygen isotope (δ18O) compositions of fossil brachiopod shells can be used to interpret paleoclimatic and paleoceanographic conditions. However, the initial isotopic composition of the living shells might be modified by diagenetic alteration. To assess the degree of this modification, we analyzed δ13C and δ18O and three common indicators of alteration in shells: minor element (manganese (Mn), iron (Fe), and strontium (Sr)) concentrations; cathodoluminescence (CL)/non-luminescence; and the shell microstructure of fossil Terebratalia coreanica and Laqueus rubellus (rhynchonellate brachiopod) shells from an exposure of conglomerates of the Tentokuji Formation (Pliocene, 3.85–2.75 Ma) in northeastern Japan. Two indices were used to quantify the preservation state of shell microstructure: the altered fiber ratio (AFR) and the altered fiber and puncta-filling cement ratio (AF-PCR). We qualified the degree of luminescence by measuring the mean cathodoluminescence index (MCLI), defined as the mean R values in a particular area of a CL image with RGB colors. The δ13C and δ18O values were negatively correlated with AFR or AF-PCR and MCLI. The sampling spots with high Mn and Fe concentrations also exhibited relatively low δ13C and δ18O. The δ13C and δ18O were more strongly correlated with Mn concentration than with Fe concentration. Therefore, of the three minor elements examined in this study, Mn concentration is the most reliable indicator of meteoric diagenesis in the studied shells. Unlike Mn and Fe concentrations, Sr concentrations in the modern and fossil brachiopod shells were similar, with overlapping ranges. This indicates that Sr concentration is not likely to be a good indicator of diagenetic alteration in the studied shells. Our study provides further evidence that multiple criteria should be applied and cross-checked when assessing diagenetic alteration of brachiopod shells. [ABSTRACT FROM AUTHOR]

In this study, InAlN was grown on glass substrates using pulsed sputtering deposition (PSD) at room temperature (RT) and was applied to thin-film transistors (TFTs). The surface flatness of the InAIN films was improved by reducing the growth temperature from 350 °C to RT. Further, the electron mobility and concentration of the InAlN film that was grown at RT were observed to be strongly dependent on the In composition. It was also observed that the electron concentration could be reduced during the introduction of Al atoms into InN, which could most likely be attributed to the reduction in the position of the Fermi level stabilization energy with respect to the conduction band edge. Further, InAlN-TFT was fabricated, and successful operation with a field-effect mobility of 8 cm2 V−1 s−1 was confirmed. This was the first demonstration of the operation of TFTs based on the growth of InAlN on an amorphous substrate at RT. [ABSTRACT FROM AUTHOR]