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In Asia, Culex mosquitoes are of particular interest because of their role in maintaining endemic mosquito-borne viral diseases, including the Japanese encephalitis virus (JEV). Nonetheless, host-feeding preferences, along with naturally infecting RNA viruses in certain Culex species, remain understudied. In this study, selected blood-fed mosquitoes were processed for avian and mammalian blood meal source identification. Concurrently, cell culture propagation and high-throughput sequencing (HTS) approaches were used to determine the RNA virome of Culex mosquitoes collected in Ishikawa Prefecture, Japan. The identification of blood meal sources from wild-caught Culex spp. revealed that Culex (Culex) tritaeniorhynchus Giles, 1901, has a robust preference toward wild boar (62%, 26/42), followed by heron (21%, 9/42). The other two species, Culex (Oculeomyia) bitaeniorhynchus Giles, 1901, and Culex (Culex) orientalis Edwards, 1921, showed a distinct preference for avian species, including migratory birds. From the HTS results, 34 virus sequences were detected, four of which were newly identified virus sequences of unclassified Aspiviridae, Qinviridae, Iflaviridae, and Picornaviridae. The absence of observable cytopathic effects in mammalian cells and phylogenetic analysis suggested that all identified virus sequences were insect-specific. Further investigations involving other mosquito populations collected in different areas are warranted to explore previously unknown vertebrate hosts that may be linked to JEV dispersal in nature.

1. Introduction Atomic layer depositions (ALD) of Al2O3 films are very essential technique to realize next generation electronic devices thanks to their high-k properties [1]. However, ALD-Al2O3 films usually suffer blistering during thermal treatments, which have caused serious problems for decades in the field of device fabrication [2]. Many groups have studied the cause of this phenomenon, and various models have been proposed. such as, stress at the interface between Al2O3 and Si [3], diffusion of Si atoms at the interface[4], residual H2O in the film after the ALD process [5], and aggregation of hydrogen atoms at the Al2O3/Si interface [6], and so on. However, the actual mechanism has hitherto remained unclear due to a lack of conclusive evidence. Here, in this study, we have tried to reveal the origin of this phenomenon using spectroscopic measurements [7]. As a result, we have succeeded in directly identifying the gas inside the blisters, which can be a concrete evidence to reveal the roots of a phenomenon that has long been obscured. 2. Experimental Procedure In the experiment, (100) oriented Si substrates with resistivity of 0.1-0.5 W∙cm were carried out. After cleaning the substrates by acetone, sulfuric-acid hydrogen-peroxide mixture solution, and hydrofluoric acid solution, all the substrates were loaded into ALD chamber which was heated up to 300oC. Then, Al2O3 layer with ~108 nm thickness was deposited on the substrates with conventional thermal ALD process using trimethylaluminum (TMA) and H2O as precursor gasses. After deposition, samples were annealed in rapid thermal annealing (RTA) furnace for 5 min with 400 – 1000 oC at N2 ambient. Finally the samples were characterized by laser microscopy, field emission scanning electron microscopy (FE-SEM), spectroscopic ellipsometry, and Raman spectroscopy. 3. Results and Discussions Figs. 1(a) and 1(b) show typical microscopic image of sample before, and after RTA (500oC, 5 min), respectively. We can clearly see that several blisters appear by annealing the samples, while there was no such sign before annealing. From the microscopic observations, we have summarized density of blisters as a function of RTA temperature in Fig. 2. Here, we can clearly see that by increasing RTA temperature, blister density increases, which is largely consistent with a previous result reported by O. Beldarrain et al, where 400-cycle Al2O3 layers were grown at 200 oC. To discuss the origin of the blister, we have conducted cross-sectional SEM observations of the formed blisters. Fig. 3 shows a typical SEM image of a blister after annealed at 500oC. The cross-sectional SEM observations clearly show that the blisters are completely hollow underneath. The surface of the flat Si substrate can also be seen under the blister, indicating that the upper Al2O3 film has completely delaminated from the interface between Si and Al2O3. From these results, we have speculated that blistering of Al2O3 after annealing is due to outgassing from the Al2O3/Si interface. Here, we came up with an idea that by identifying the gas inside the blisters, we can clarify the cause of this phenomenon. To identify the content inside blisters, Raman spectroscopy was carried out. The 532 nm wavelength laser used for Raman measurements can pass completely through Al2O3, making it possible to measure the gas inside without destroying the blisters. Fig. 4 shows a typical result of the Raman measurement of a blister of a sample after RTA (500oC). Here, as a result, characteristic spectra with peaks at positions ~4126, ~4144, ~4156, and ~4162 cm-1 were successfully observed. These four peaks can be assigned as peaks due to the difference in the rotational-quantum-number (J) of H2 as shown in Fig. 4, which is typical spectra of free H2 gas. These results provide evidence that blister formation is caused by the generation of hydrogen gas from the Al2O3/Si interface, a finding that is of great importance in clarifying the physics of blister formation mechanisms. In the presentation, we will also present details on the physics of hydrogen gas generation and methods to suppress blister formation. [References] [1] R. Zhang, et al., IEEE Trans. Electron Devices 59, 335-341, (2012). [2] G Dingemans, et al., J. Vac. Sci. Technol. A, 30, 040802, (2012). [3] J. Thurn., et al., J. Mater. Sci. 39, 4799, (2004) [4] M. Broas, et al., Appl. Phys. Lett. 111, 141606, (2017) [5] O. Beldarrain, et al., J. Vac. Sci. Technol. A, 31, 01A128 (2013) [6] D. G. Xie, et al., Nat. Mater., 14, 899, (2015). [7] R. Matsumura, et al., accepted to ACS Applied Materials & Interfaces, https://doi.org/10.1021/acsami.1c20660 Figure 1

In recent years, germanium (Ge) has attracted a lot of attention for the development of next generation devices due to its higher carrier mobilities compared with silicon (Si) and its compatibility for complementary metal-oxide-semiconductor (CMOS) applications. It is widely known that Ge is an indirect-band semiconductor like Si. However, by introducing tensile strain, the 136 meV difference between direct and indirect gaps can be reduced. Furthermore, in the case of 0.2-0.3% tensile strained Ge, n-type doping in the order of 1019 cm-3 were expected to be resulted in quasi direct-band light emission around 1550 nm wavelength. [1] The realization of this tensile strained n-Ge is promising for the integration of light sources on next generation Ge-based devices. Here, we focused on n-type Ge deposition using molecular beam epitaxy (MBE) method and have succeeded in realizing highly Sb-doped epitaxial n-Ge films by modulating the deposition temperatures. [2] Moreover, we have recently reported the crystallization of amorphous Ge by high-speed continuous wave laser annealing (CWLA), which more importantly also resulted in the introduction of 0.55-0.62% tensile strain. [3] In this study, we applied the similar annealing technique for crystallization of Sb-doped Ge toward the realization of tensile strained n-type Ge films. Sb-doped poly-crystalline Ge films with high Sb concentration (approximately 1019 cm-3) and thickness of about 100 nm were deposited on quartz substrate by molecular beam deposition at 450ºC substrate temperature. Then, 300 nm of SiO2 capping layer was deposited by sputtering in room temperature, such that the sample structure become that shown in Fig.1(a). The samples then annealed in the CWLA system equipped with Nd:YVO4 solid state laser with wavelength of 532 nm as the light source, which scan laser light at the speed (vscan) of 800 m/min. Also, the laser is focused to 20 μm diameter and shifted at 5 μm to scan the samples. Here, the laser power (Elaser) was changed from 300 to 1000 mW. After laser annealing, the capping layer were removed then the samples were characterized by micro-Raman spectroscopy. The annealed sample surface shows brighter contrast compared to the as-deposited samples, as shown in Fig.1(b) and (c), which indicate the structural change of Ge layer. Raman spectra measured at surface of annealed Ge layers are summarized in Fig.2. Here, Ge-Ge peak around 300.2 cm-1 confirmed on the samples, indicating the crystallization of the Ge layers. This peak is not shifted in low Elaser but largely shifted in high Elaser at up to -2.4 cm-1 for undoped and -3.6 cm-1 for the Sb-doped Ge films. This difference could be explained by the liquid phase recrystallization after Ge layer melted in high Elaser (≥600 mW). During recrystallization process, tensile strain is accumulated upon cooling as the tensile strain amount (0.43-0.63%) is agree with the thermal expansion value of Ge between solidification temperature and room temperature (-0.60%). This mechanism is similar to the crystallization of amorphous Ge films on quartz substrates in our previous work. [3] These results show the successful crystallization of tensile strained n-Ge layer by the CWLA method. This finding will be useful for the growth of Ge-based films and a promising step toward the development of CMOS-integrated optoelectronics. Further investigation of the annealing conditions and its relations with the properties of Sb-doped Ge films will be discussed in the main presentation. References Liu, J., Kimerling, L. C. & Michel, J. Semicond. Sci. Technol. 27, (2012). Saputro, R.H., Matsumura, R. & Fukata, N. Cryst. Growth & Des. 21, 6523–6528 (2021). Matsumura, R. & Fukata, N. ECS J. Solid State Sci. Technol. 9, 063002 (2020). Figure 1

Heavily doped n-type Ge crystals are essential for Ge-based electronics and optical applications. In this report, we describe the mechanism of dopant redistribution via out-diffusion and re-evapora...

In recent years, Ge-based semiconductor materials has attracted a lot of attention for its possibility of higher mobility channel formation, toward next-generation complementary metal-oxide-semiconductor (CMOS) transistors. For this material to reach its potential, formation and optimization of p-n junction, which is the fundamental structure for a practical device, need to be investigated. In most cases, dopant ions are injected to form dopant-enriched films at the semiconductor interface, followed by annealing with various possible techniques1. However, crystal damages caused by high implantation energy makes it difficult to recrystallize and activate the dopant atoms. In this research, in-situ doping of Sb in epitaxial Ge layers grown on crystalline p-Ge substrates were studied, aiming a vertical p-n diode with higher Sb doping while maintaining good crystal quality. Formation of highly doped n-Ge is one of the most crucial challenges, as it was reported that uniform doping distribution across the layers are difficult to be achieved, which potentially deteriorate the crystallinity of the n-Ge layer2,3. Therefore, a study to overcome the doping problems in n-Ge, can lead to wider application of Ge-based devices. The p-Ge substrates were treated by ultrasonic cleaning in Acetone followed by a diluted-HF dip and de-ionized water rinse. The cleaned substrate then loaded into molecular beam epitaxy (MBE) chamber (base pressure of 10-8 Pa) and subjected to thermal cleaning at 450 ºC for 10min. Subsequently, Ge film were homo-epitaxially grown on the p-Ge substrate using the Knudsen cell (K-cell) that heated around 1100 ºC to maintain a fixed 0.2 Å/s deposition rate. At the same time Sb source was evaporated by heating the Sb K-cell (Tdop.: 325-400 ºC) for the in-situ doping deposition. Here, the depositions of Sb-doped Ge layer were performed on the p-Ge substrate at fixed temperature of 450 ºC. The Sb contents in the epitaxial layer were quantitatively evaluated by the secondary ion mass spectrometry (SIMS), and a reflection high-energy electron diffraction (RHEED) system equipped on the MBE chamber was used to monitor the epitaxial growth during depositions. Moreover, the crystal quality also characterized by the Raman spectroscopy method. After the deposition of 100 nm Sb-doped Ge layer, the samples then used to form vertical p-n diode structures using a conventional lithography method as shown in Fig. 1. The depth profiles obtained by SIMS measurements shows that high amount of Sb atoms (>1019 cm-3) was incorporated into the epitaxial Ge layer (Fig 2(a)). It also shows that Sb atomic concentrations vary with the Sb K-cell temperatures (Tdop.), in which higher temperature (Tdop.: 400 ºC) resulted in higher Sb concentration. The epitaxial growth of Sb-doped Ge layer was observed using the RHEED system, which resulted in a streaky pattern of the diffracted electron beam as seen in the inset of Fig. 2(b). The crystallinity of the epitaxial layer also matched with the results obtained by of Raman measurement shown in Fig.2(b). A strong Ge-Ge phonon peak at similar position to the reference crystalline Ge (at 300.2 cm-1) was obtained for both Tdop.: 325 ºC and 400 ºC samples. This result indicates the growth of Ge crystals with high crystallinity despite the high Sb content. Fig. 2(c) shows rectifying properties for vertical p-n junctions using these samples, where the current obtained at forward bias is much higher than that obtained at reverse bias (ION >> IOFF ). Interestingly, this p-n diode rectifying behavior was also improved (higher ION /IOFF ratio) with the increase of dopant concentrations. The relation between Sb concentration and electrical properties can be explained by the dopant activation rate in the Sb-doped Ge layer, because higher amount of Sb atoms increases the electron doping density. This result clearly shows that highly doped n-Ge layer was formed on the top of p-Ge. This can be expected a useful method for the formation of next-generation vertical transistors where n+-Ge is utilized in source/drain formation. Further investigation about the growth conditions and its relations with electrical properties of the vertical p-n diodes will be discussed in the main presentation. References Sgourou, E. N., Panayiotatos, Y., Vovk, R. V., Kuganathan, N. & Chroneos, A. Diffusion and dopant activation in germanium: Insights from recent experimental and theoretical results. Appl. Sci. 9, (2019). Yurasov, D. V. et al. Antimony segregation in Ge and formation of n-type selectively doped Ge films in molecular beam epitaxy. J. Appl. Phys. 118, (2015). Sawano, K. et al. Ultrashallow Ohmic contacts for n-type Ge by Sb δ -doping. Appl. Phys. Lett. 97, 2008–2011 (2010). Figure 1

This study aimed to clarify how the power-assist function of the hybrid assistive limb (HAL®), an exoskeleton-type gait-assist device, affected the gait characteristics of patients who wear it, specifically focusing on the “misalignment” of the robot joints and landmarks with the corresponding body parts. Five healthy adult men were video-recorded wearing the HAL® as they walked normally on a treadmill under seven conditions corresponding to the strengths and sites of robotic power assistance. For kinematic analysis, reflective markers were attached to the HAL® and the wearer at key locations, and participants were recorded walking past a set of four video cameras for each condition. A motion analysis system was used for analysis. The walking motion was segmented into eight-phase gait cycles. Knee misalignment, or the relative offset in position of the HAL®/wearer knee joints, was calculated from kinematic data and joint angles. These values were compared with respect to two factors: assist level and gait phase. Statistical analysis consisted of parametric and nonparametric tests for comparing the values of misalignment of each gait phase, followed by multiple comparisons to confirm significant differences. The results showed that the knee misalignment was greatest in the pre-swing phase and was significantly lower overall in conditions with high levels of power assistance. The result of greater knee misalignment in the pre-swing phase may be attributed to the structural properties of the HAL® lower-limb exoskeleton. This provides valuable insight regarding the walking stages that should be given special attention during the evaluation of synchrony between exoskeleton-type gait-assist robots and their wearers.

Some patients with schizophrenia have impaired hypothalamic-pituitary-adrenal axis function. However, there is a dearth of studies focusing on corticotropin-releasing hormone (CRH) levels in the brains of schizophrenia patients, which motivated us to examine whether cerebrospinal fluid (CSF) CRH concentrations are altered in these patients. We also examined the possible correlation of CSF CRH level with clinical variables such as schizophrenia symptoms and antipsychotic medication. The study population comprised 20 patients with a diagnosis of schizophrenia according to DSM-5 criteria and 25 healthy controls, who underwent lumbar puncture. Most of the patients were treated with antipsychotic drugs and their doses were converted to chlorpromazine (CP) equivalent values. CSF CRH concentrations were measured by an enzyme immunoassay. Symptom severity was assessed using the Positive and Negative Syndrome Scale (PANSS). There was a significantly lower CSF CRH concentration in the patients than in the controls (Mann-Whitney U test: p = 0.014). A significantly negative correlation of CSF CRH levels with PANSS negative scores was found in the patients (Spearman's: ρ = −0.58, p = 0.007). However, CSF CRH concentrations were not significantly correlated with the PANSS total (ρ = −0.035, p = 0.89), positive (ρ = 0.25, p = 0.30), or general psychopathology (ρ = 0.13, p = 0.59) scores. No significant correlation was found with CP equivalent values (ρ = 0.00, p = 1.00). In conclusion, we found that the patients with schizophrenia had lower CSF CRH concentrations compared to the controls and that the lower CSF CRH was associated with negative symptoms of the illness. Further studies in a larger sample and in drug-free patients are warranted.

Aim The ε4 allele of apolipoprotein E gene (APOE) is a well‐known risk factor of late‐onset Alzheimer's disease. However, little is known why this variant confers a risk for Alzheimer's disease. The aim of this study was to examine the influence of the APOE genotype on cerebrospinal fluid (CSF) protein levels. Methods The present study performed a secondary analysis on our previously generated database to compare the CSF levels of 1128 proteins between APOE‐ε4 carriers (28 subjects) and noncarriers (104 subjects). All subjects were physically healthy Japanese individuals without dementia. Results CSF levels of apoE2, apoE3, and apoE4 were significantly higher (all nominal P, The CSF levels of apoE2, apoE3, and apoE4 were higher in APOE‐ε4 carriers. The CSF levels of TNF‐α were significantly lower in APOE‐ε4 carriers. Our findings indicate the possible roles of apoE and TNF‐α in the pathogenesis of APOE‐ε4‐associated Alzheimer's disease.

To examine the role of neuroplasticity in the pathology of psychiatric disorders, we measured cerebrospinal fluid (CSF) neuroplasticity-associated protein levels. Participants were 94 patients with schizophrenia, 68 with bipolar disorder (BD), 104 with major depressive disorder (MDD), and 118 healthy controls, matched for age, sex, and ethnicity (Japanese). A multiplex immunoassay (22-plex assay) was performed to measure CSF neuroplasticity-associated protein levels. Among 22 proteins, 11 were successfully measured in the assay. CSF amyloid precursor protein (APP) and glial cell-derived neurotrophic factor (GDNF) levels were significantly lower in patients with schizophrenia, and CSF APP and neural cell adhesion molecule (NCAM)-1 levels were significantly lower in patients with BD, than in healthy controls (all p p p p p

Ge1-xSnx nanowires (NWs) have been a focus of research attention for their potential in realizing next-generation Si-compatible electronic and optoelectronic devices. To control the growth of NWs and increase their Sn content, the growth mechanism needs to be understood. The use of Au-Sn alloy catalysts instead of Au catalysts allows an easier understanding of Ge1-xSnx NW growth, and the effects of Sn at different concentrations in catalysts on growth direction, Sn incorporation, and crystallinity of Ge1-xSnx NWs can be clarified. High Sn content in Au-Sn alloy catalysts favors ⟨110⟩-oriented NW growth and high Sn incorporation in NWs. The higher Sn content in Au-Sn alloy catalysts also improves the crystallinity of NWs.

Lipidomics provides an overview of lipid profiles in biological systems. Although blood is commonly used for lipid profiling, cerebrospinal fluid (CSF) is more suitable for exploring lipid homeostasis in brain diseases. However, whether an individual’s background affects the CSF lipid profile remains unclear, and the association between CSF and plasma lipid profiles in heathy individuals has not yet been defined. Herein, lipidomics approaches were employed to analyze CSF and plasma samples obtained from 114 healthy Japanese subjects. Results showed that the global lipid profiles differed significantly between CSF and plasma, with only 13 of 114 lipids found to be significantly correlated between the two matrices. Additionally, the CSF total protein content was the primary factor associated with CSF lipids. In the CSF, the levels of major lipids, namely, phosphatidylcholines, sphingomyelins, and cholesterolesters, correlated with CSF total protein levels. These findings indicate that CSF lipidomics can be applied to explore changes in lipid homeostasis in patients with brain diseases.

A tandem reaction combining direct H2O2 production from H2 and O2 and a subsequent oxidation reaction with H2O2 in a single reaction vessel offers an energy-saving and cost-effective oxidation route for the synthesis of targeted chemicals. Herein, we report the synthesis of hollow titanosilicate nanospheres encapsulating Pd and PdAu alloy nanoparticles (NPs) for the H2O2-mediated one-pot oxidation reaction. The yolk–shell nanostructured catalyst (Pd@Ti-HMSS), composed of a Pd NP core encapsulated within a hollow mesoporous titanosilicate shell having isolated Ti atoms, is fabricated by a facile etching and re-assembly process using SiO2 spheres as a template and two different kinds of Si alkoxides as precursors. The synthesized catalyst shows superior catalytic activity in the one-pot oxidation reaction of sulfide under a co-flow of H2 and O2, and far outperforms the prototype titanosilicate-supported Pd NP catalysts. Detailed structural characterization and kinetic analysis reveal that the increased catalytic efficiency is attributed to efficient mass transfer of reactants and the associated improved reactivity with in situ generated H2O2 over Ti sites. A further enhancement in activity is achievable by encapsulating PdAu alloy NPs, which provide a faster H2O2 production rate than monometallic Pd NPs. Owing to the presence of a protective silicate shell, the catalyst shows good stability and reusability over multiple catalytic cycles without significant loss of activity.

When a beam of light excites a single spot on a thin luminescent layer embedded in a planar waveguide, a concentric re-emission pattern is observed. An analytical expression is formulated by following the series of events in the waveguide: generation of angle-dependent photoluminescence spectra, reflection at the waveguide–air boundary, absorption by the luminescent layer, and generation of next-generation photoluminescence. The formula reproduces the peak radii observed in the experiments with some organic dyes. It provides insights for the re-emission events in a luminescent solar concentrator and the cross talk in an energy-harvesting display based on photoluminescence.

Polycrystalline Si thin films on insulating substrates have been widely used to fabricate thin film transistors. However, since randomly induced grain boundaries in the polycrystalline thin films have been degrading transistor performance, application of thin film transistors has been limited to low speed processing units such as display drivers. Here, in this letter, we have tried to realize single grain growth of Si thin film at controlled position. Aluminum induced layer exchange crystallization of Si thin film was performed at limited region to suppress spontaneous nucleation during the crystal growth, and thus, single grain Si thin films have been successfully realized on quartz glass substrates. This technique will open up a way to realize high speed processing thin film transistors.

To realize next generation electronics and energy harvesting, crystal growth of silicon-germanium thin film on insulating substrate was investigated by high-speed continuous wave laser annealing. As a result, growth of polycrystalline (poly-) SiGe thin films on insulating substrate became possible. Furthermore, by tuning the laser annealing conditions, we have succeeded in controlling the Si concentration profiles after growth in a wide range from uniform to laterally graded distributions. These results and discussions will facilitate the development of next-generation electronics, and energy harvesting devices.

Low power consumption is one of the most important requirements for present and future integrated systems. Here, reduction in supply voltage is most effective in power reduction. Low supply voltage operation of charge-based logic switch devices can be achieved by steep slope devices with lower sub-threshold swing (S.S.) than CMOS. For this purpose, tunnel FETs (TFETs) have recently stirred a strong interest [1, 2], because of the high compatibility with CMOS platform. Here, materials with small and/or direct band gap such as III-V and Ge are preferred to enhance Ion of TFETs. In addition, type-II hetero-structures are known to be effective in boosting the TFET performance [1-3]. One of the critical technological challenges of pn-junction-based TFETs is the source junction engineering allowing us to form the source junctions with steep impurity profiles and low defect density for optimal Ge/III-V and/or hetero-interface materials. In addition, another key factor is low defect densities in the channel/junction regions and at the MOS interfaces. The MOS interface defects can include fast interface states, slow states and tail states near the band edges, while the reduction in the defect densities is not easy for other materials than Si. Thus, the channel and gate stack engineering for realizing defect-less structures are also quite important. From the above viewpoints, we are currently working for the following material systems and source doping technologies [2-4], (1) InGaAs TFET with Zn diffusion source (2) GaAsSb (source)/InGaAs (channel) TFETs with Be in-situ doping (3) Ge (source)/strained Si (channel) TFETs with B in-situ doping. Here, Zn diffusion into InGaAs can automatically form pn junctions with steep Zn profile, because of the diffusion constant of Zn strongly dependent on Zn concentration [5, 6]. We experimentally confirmed the steep Zn profile and lower leakage current of InGaAs p-n junctions by solid phase diffusion from SOG films, attributed to the defect-less junction formation. Quantum-well InGaAs/InAs(3nm)/InGaAs n-TFETs with the Zn-diffused source regions and W/HfO2/Al2O3 gate stacks have exhibited the minimum S.S. value of 55 mV/dec and I60 (maximum source/drain current with S.S. less than 60 mV) of 0.7 nA/um at room temperature [3, 6]. In comparison with InGaAs homo-junction TFETs, III-V TFETs composed of type-II hetero-structures, GaSb/InAs and GaAsSb/ InGaAs, are expected to provide superior electrical characteristics, because of the smaller effective bandgap. We fabricated vertical n-TFETs using in-situ Be-doped p+-GaAs0.51Sb0.49/ In0.53Ga0.47As grown on InP by MOMBE [3, 7]. The steep Be profile of 11 nm/dec. is obtained, thanks to the in-situ doping of Be during the GaAsSb growth. We confirmed the operation of GaAsSb/InGaAs TFETs through observation of the negative differential resistance under forward bias condition. However, high leakage current attributable to defects in the source junction significantly degrades the performance at 297 K. The characteristics at 20 K with S.S. of 82 mV/dec. are regarded as the TFET performance dominated only by tunneling. Another type of type-II hetero-interface n-TFETs has been realized by p+Ge/strained SOI structures [3, 4, 8, 9]. Here, higher valence band edge of the source due to Ge and lower conduction band edge of the channel due to bi-axial tensile strain are combined to form the type-II band line-up. p+Ge/SOI with tensile strain of 0.8 and 1.1 % were fabricated by using bi-axial strained SOI substrates and in-situ B doping during Ge MBE growth. The higher Ion and lower S.S.min were obtained by applying tensile strain. The unstrained, 0.8 and 1.1 % strained SOI TFETs after 400 oC PMA [9] yield S.S.min of 69, 48 and 29 mV/dec. and Ion/Ioff of 4.4, 2.2 and 3.7x107, respectively, at room temperature. This work has partly been supported by JST-CREST. The authors would like to thank Drs. M. Yokoyama, O. Ichikawa, H. Yamada and T. Yamamoto in Sumitomo Chemical Corporation, Drs. M. Mitsuhara, H. Sugiyama, Hoshi and H. Yokoyama in NTT for their collaborations. References [1] A. C. Seabaugh et al., IEEE Proc. 98, 2095 (2010) [2] S. Takagi et al., Symp. VLSI Tech., T22 (2015) [3] S. Takagi et al., IEDM, 516 (2016) [4] S. Takagi et al, Solid State Electron. 125, 82 (2016) [6] S. Takagi et al, IEDM, 516 (2016) [5] M. Noguchi et al., J. Appl. Phys. 118, 045712 (2015) [6] D. H. Ahn et al., Symp. VLSI Tech., 224 (2016) [7] T. Gotow et al., SSDM, 21 (2016) [8] M. Kim et al., Thin Solid Films 557, 298 (2014) [9] M. Kim et al., IEDM, 331(2014)

Neural cell adhesion molecule (NCAM) plays an important role in neural plasticity, and its altered function has been implicated in psychiatric disorders. However, previous studies have yielded inconsistent results on cerebrospinal fluid (CSF) NCAM levels in psychiatric disorders. The aim of our study was to examine CSF NCAM levels in patients with schizophrenia, bipolar disorder (BD), and major depressive disorder (MDD), and their possible relationship with clinical variables.The participants comprised 85 patients with schizophrenia, 57 patients with BD, 83 patients with MDD and 111 healthy controls, all matched for age, sex, and Japanese ethnicity. The CSF samples were drawn using a lumbar puncture and NCAM levels were quantified by an enzyme-linked immunosorbent assay.Analysis of covariance controlling for age and sex revealed that CSF NCAM levels were lower in all patients (p=0.033), and in those with BD (p=0.039), than in the controls. NCAM levels positively correlated with age in patients with BD (p0.01), MDD (p0.01), and the controls (p0.01). NCAM levels negatively correlated with depressive symptom scores in patients with BD (p=0.040). In patients with schizophrenia, NCAM levels correlated negatively with negative symptom scores (p=0.029), and correlated positively with scores for cognitive functions such as category fluency (p=0.011) and letter fluency (p=0.023) scores.We showed that CSF NCAM levels were lower in psychiatric patients, particularly bipolar patients than in the controls. Furthermore, we found correlations of NCAM levels with clinical symptoms in patients with BD and in those with schizophrenia, suggesting the involvement of central NCAM in the symptom formation of severe psychiatric disorders.

In this research, we tackle the challenge of picking only one object from a randomly stacked pile where the objects can potentially be tangled. No solution has been proposed to solve this challenge due to the complexity of picking one and only one object from the bin of tangled objects. Therefore, we propose a method for avoiding the situation where a robot picks multiple objects. In our proposed method, first, grasping pose candidates are computed by using the graspability index. Then, a Convolutional Neural Network (CNN) is trained to predict whether or not the robot can pick one and only one object from the bin. Additionally, since a physics simulator is used to collect data to train the CNN, an automatic picking system can be built. The effectiveness of the proposed method is confirmed through experiments on robot Nextage and compare with previous bin-picking methods.

Aim Ethanolamine-containing phospholipids are synthesized in endoplasmic reticulum (ER) and mitochondria. ER stress and mitochondrial dysfunction have been implicated in bipolar disorder (BP). In this study, we aimed to examine the relationship of ethanolamine plasmalogen (PLE) and phosphatidylethanolamine (PTE) levels in blood plasma with BP. Methods Plasma PLE and PTE levels were compared between 34 patients with BP (DSM-IV) and 38 healthy control participants matched for age, sex, and ethnicity (Japanese). Furthermore, the relationships of plasma PLE and PTE levels with clinical variables were explored. Results Plasma PLE levels were significantly lower in patients with BP than in healthy controls (P = 0.0033). In subgroup analyses, plasma PLE levels were significantly lower in patients with BP type I (BP I) than in healthy controls (P = 0.0047); furthermore, plasma PTE levels were significantly lower in patients with BP I than in controls (P = 0.016) and patients with BP type II (BP II) (P = 0.010). Receiver-operating characteristic curve analysis revealed that the discriminatory power of plasma PTE levels for distinguishing between BP I and II was fair (area under the curve = 0.78; P = 0.0095). There were no significant correlations of plasma PLE or PTE levels with depression or manic symptoms in patients. Conclusions Plasma PLE and PTE levels were associated with BP I, but not with BP II. Moreover, plasma PTE levels differed between patients with BP I and II. Our findings highlight the importance of ethanolamine phospholipids in the pathophysiology of BP, especially BP I.

Ge

1. Introduction Thanks to their high carrier mobility, germanium based group IV semiconductors are promising materials to realize next generation electronics [1]. Especially, germanium tin alloys (GeSn) having high Sn concentration (> 6 at. %) are attracting much attention due to their direct band structure [2]. To apply such significant advantage to thin-film devices such as thin-film transistors (TFTs) or three dimensional large-scale integrated circuits (3D-LSIs), various groups are working on to crystallize these materials on insulating substrates by various approaches such as germanium condensation [3], solid phase crystallization [4], and so on. Recently, we have established a technique to grow highly strained germanium based materials on insulating substrates by microsecond annealing using novel high speed continuous wave laser annealing (CWLA) system [5]. Here, in this presentation, we will introduce our recent achievements in GeSn crystal growth by the microsecond annealing technique. 2. Experimental Procedure In the experiment, amorphous GeSn films with Sn concentration of 15% (thickness: 100 nm) were firstly deposited on quartz substrates by molecular beam deposition. Then the samples were annealed by the high speed CWLA system, which can scan laser light (focused to 20 μm diameter) on samples with very high speed up to 15 m/s. The laser irradiation time (tirr) can be varied from 1.5 to 6.0 μs by controlling the scanning speed. Here, Nd:YVO4 solid state laser with wavelength of 532 nm was used as a light source, and laser power was controlled from 350 to 1000 mW. After the laser annealing, the samples were characterized by microscopic Raman spectroscopy and electron back scattered diffraction (EBSD) method. 3. Results and Discussions Fig. 1(a) shows Nomarski microscopic image after laser annealing (500 mW, tirr: 1.5 μs), which shows bright contrast at annealed region. Raman signals measured at surface of GeSn thin film before and after LA (tirr: 1.5 μs) are shown in Fig. 1(b). We can see clear peak around 300 cm-1 due to Ge-Ge atomic bond at the annealed region, which supports that GeSn film has been successfully crystallized by the annealing. To discuss about the growth feature of GeSn films, EBSD measurements were carried out. Mapping images of Ge and Sn phase signals at surfaces of samples are summarized in Fig. 2 as a function of tirr. Here, we can clearly see that the area of Sn phase signal is expanding by increasing tirr. These results (Raman and EBSD) suggest that by increasing tirr, Sn precipitation toward surface of GeSn occurs after crystallization of GeSn films, due to excess annealing. As a result, by increasing tirr, substitutional Sn concentration in the films decreases after LA [Fig. 3], showing that short time annealing is essential to prevent the precipitations. Fig. 4 summarizes substitutional Sn concentration in GeSn films grown with shortest irradiation time (1.5 μs) as a function of laser power. By minimizing the irradiation time and tuning laser power to minimum value for crystallization, we could realize GeSn thin films with a high substitutional Sn concentration (13 %) on insulating substrates. These are very attracting results to realize next generation electronics. Detailed physics and further tin concentration improvement methods will be discussed in the presentation. [References] [1] J.R. Haynes, W. Shockley, Phys. Rev. 81 835–843 (1951). [2] S. Gupta, K. C. Saraswat, et.al., J. Appl. Phys. 113 073707 (2013). [3] S. Nakaharai, S. Takagi, et. al., J. Appl. Phys. 105 024515 (2009). [4] K. Toko, et. al., Sci. Rep., 7, 16981 (2017) [5] R. Matsumura, N. Fukata, ECS J. Solid State Sci. Technol, 9 063002 (2020). Figure 1

We demonstrate the crystallization of thermally deposited amorphous germanium (Ge) microstrips on single layer graphene (SLG) by rapid melting growth. Lateral growth of large grain crystalline Ge was successfully obtained over entire microstrip structure. SLG has shown its capability to suppress the spontaneous nucleation in the melting Ge, where no or less intermixing of C and Ge atoms has been detected. The interaction of C atoms from the graphene and Ge atoms at the interface is the possible reason for the observation of large compressive strain generated in the Ge strip grown on SLG. This technique provides an innovative breakthrough towards the realization of single-crystalline Ge-on-insulator (GOI) structure on SLG to facilitate the next-generation ultra-large-scale integrated circuits (ULSIs) with multifunctionalities.

Low-temperature formation of Sn-doped Ge on insulator is desired to realize next generation flexible electronics. To achieve this, metal-induced crystallization (MIC) of a-GeSn is investigated. By MIC of a-GeSn with initial Sn concentration of 5%, Sn-doped Ge is obtained at low temperatures ( Introduction A technique for low-temperature (≤250°C) formation of high-quality crystalline Ge films on insulator is expected to realize advanced high performance thin film transistors (TFT) on flexible plastic substrates (softening temperature: ~300oC). To improve quality of Ge crystals, Sn-doping (2layers [2]. However, the growth temperature (425°C) reported to date is higher than the softening temperatures of plastic substrates. To decrease the growth temperature of Sn-doped Ge, in the present study, we investigate metal-induced crystallization (MIC) of a-GeSn. This successfully decreases the growth temperature below 250°C. Experimental Procedure Fig.1 schematically shows the procedure of sample preparation. Amorphous Ge1-xSnx layers (x: 0-0.2, thickness: 100 nm) were deposited on quartz substrates at room temperature. Then, Au layer patterns were formed on the amorphous GeSn layers. The samples were annealed at 150-250oC for 10-60 min to induce lateral growth in a N2ambient. The growth characteristics were analyzed by Nomarski optical microscopy and microprobe Raman spectroscopy. Results and Discussion Figs. 2(a) and 2(b) show Nomarski optical micrographs of Ge1-xSnx (x: 0.05 and 0.2, respectively) samples after annealing at 250oC for 10 min. Au pattern regions are located in the left side areas of the micrographs. In the case of the low Sn concentration (5%), different contrast regions are observed around the Au patterns, as indicated by the broken lines. On the other hand, the sample with the high Sn concentration (20%) shows no change around the Au pattern after annealing. The Raman spectra obtained from these samples are summarized in Fig. 2(c). In Raman spectra #1 for the low Sn concentration (5%), a sharp peak due to Ge-Ge bonding in c-Ge is clearly observed. On the other hand, no peaks are detected in spectra #3 for the sample with the high Sn concentration (20%). These results indicate that lateral growth is generated from the Au patterns for samples with the low Sn concentration (5%), while it is not generated for the high Sn concentration (20%).The lateral growth lengths at 150 and 250oC for samples with various Sn concentrations were estimated using theNomarski optical microscopy combined with line-scanning of microprobe Raman measurements. The results are summarized as a function of the annealing time in Fig. 3. In the case of low Sn concentrations ( References [1] O. Nakatsuka, et al., Jpn. J. Appl. Phys. Lett. 49, 04DA10 (2010). [2] W. Takeuchi, et al., Appl. Phys. Lett. 107, 022103 (2015). Figure 1

We demonstrate the crystallization of the microstrips of electrodeposited amorphous germanium (Ge) on graphene on insulator by rapid melting growth for the first time. Growth of single-crystalline Ge microstrips with (111) orientation was confirmed. The high level of compressive strain was found to be resulted from the intermixing of C atoms from multilayer graphene (MLG) and Ge. Probably the introduction of local C atom into Ge film enhances nucleation of Ge on MLG, which results in (111)-oriented Ge nuclei. Subsequent lateral growth enables crystallization of Ge with (111) orientation on the entire microstrip. The results also indicate that graphene is very useful to suppress the spontaneous nucleation in the melting Ge films and the lattice rotation or misorientation. This novel and innovative technique provides a breakthrough towards the realization of high quality Ge-on-insulator structures to facilitate the next-generation ultra-large-scale integrated circuits (ULSIs) with multifunctionalities.