A5042202496- Semiconductor materials and devices
- Advancements in Semiconductor Devices and Circuit Design
- Low-power high-performance VLSI design
- Magnetic properties of thin films
- Genetic diversity and population structure
- Advanced Memory and Neural Computing
- Quantum and electron transport phenomena
- Plant and animal studies
- Parallel Computing and Optimization Techniques
- Ferroelectric and Negative Capacitance Devices
- Integrated Circuits and Semiconductor Failure Analysis
- Ecology and Vegetation Dynamics Studies
- Advanced Data Storage Technologies
- Physics of Superconductivity and Magnetism
- Wheat and Barley Genetics and Pathology
- Quantum Computing Algorithms and Architecture
- Analog and Mixed-Signal Circuit Design
- Cancer Treatment and Pharmacology
- Ecology and Conservation Studies
- VLSI and Analog Circuit Testing
- Plant Taxonomy and Phylogenetics
- Genetic Mapping and Diversity in Plants and Animals
- Natural product bioactivities and synthesis
- Sesquiterpenes and Asteraceae Studies
- Semiconductor materials and interfaces
Tokyo University of Science
2016-2025
Forestry and Forest Products Research Institute
2012-2025
Daido Steel (Japan)
2021
Tokushima University
2019-2021
Hokkaido Agricultural Research Center
2018
St. Marianna University School of Medicine
2018
Yale University
2018
Tokushima Bunri University
2015
Chubu University
2010-2014
Hitachi (Japan)
2004-2013
Barium-filled skutterudites BayCo4Sb12 with an anomalously large filling fraction of up to y=0.44 have been synthesized. The lattice parameters increase linearly Ba content. Magnetic susceptibility data show that Ba0.44Co4Sb12 is paramagnetic, which implies some the Co atoms in acquired a magnetic moment. presence two different valence states (Co3+ and Co2+) leads barium even without extra charge compensation. All samples n-type conduction. electrical conductivity increases increasing...
A 1.8 V 2 Mb SPin-transfer torque RAM (SPRAM) chip using a 0.2 mum logic process with an MgO tunneling barrier cell demonstrates the circuit technologies for potential low-power nonvolatile RAM, or universal memory. This features array scheme bit-by-bit bi-directional current writing to achieve proper spin-transfer of 100 ns, and parallelizing-direction reading low-voltage bit-line preventing read disturbances that lead 40 ns access time.
A 1.8V 2Mb spin-transfer torque RAM chip using a 0.2 μm logic process with an MgO tunneling barrier cell demonstrates the circuit technologies for potential low-power non-volatile RAM, or universal memory. This features array scheme bit-by-bit bidirectional current write to achieve proper writing in 100ns, and parallelizing-direction reading low-voltage bit-line that leads 40ns access time.
Although coevolution is acknowledged to occur in nature, coevolutionary patterns symbioses not involving species‐to‐species relationships are poorly understood. Mycorrhizal plants thought be too generalist coevolve with their symbiotic fungi; yet some plants, including orchids, exhibit strikingly narrow mycorrhizal specificity. Here, we assess the evolutionary history of specificity lady's slipper orchid genus, Cypripedium. We sampled 90 populations 15 taxa across three continents, using DNA...
A 32-Mb SPin-transfer torque RAM (SPRAM) chip was demonstrated with an access time of 32 ns and a cell write-time 40 at supply voltage 1.8 V. The fabricated 150-nm CMOS 100 × 200-nm tunnel magneto-resistive (TMR) device element. required thermal stability 67 the TMR estimated by taking into account disturbances during read operations data retention periods 10 years for nonvolatile operation. SPRAM features three circuit technologies suitable large-scale array: 1) two-transistor, one-resistor...
This paper describes low-voltage random-access memory (RAM) cells and peripheral circuits for standalone embedded RAMs, focusing on stable operation reduced subthreshold current in standby active modes. First, technology trends dynamic RAMs (DRAMs) static (SRAMs) are reviewed the challenges of terms cell signal charge clarified, including necessary threshold voltage, V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</inf> , its variations MOS...
We demonstrate a new MOSFET on ultra-thin BOX that allows wide-range back-bias control in low-power and high-performance applications. The back gate is effective not only to increase the drive current by about 20% active mode but also reduce off-current an order of magnitude stand-by mode. have demonstrated tunable-threshold-voltage technology for devices with metal gates ion implantation V/sub th/ control. target applications was achieved using propose 6-transistor SRAM memory cell which we...
Te-doped CoSb3 bulk polycrystalline materials Co4Sb12−xTex have been prepared by melting, annealing, and spark plasma sintering characterized x-ray diffraction. From the lattice constants of samples, a Te substituting fraction limit for Sb is estimated to be x=0.55. The Hall effect, Seebeck coefficient, electrical-conductivity, thermal-conductivity measurements were performed between room temperature 900K. show an n-type conduction. As increases, electron concentration electrical...
We first report a multi-level-cell (MLC) spin-transfer torque memory (SPRAM) with series-connected magnetotunnel junctions (MTJs). The series MTJs (with different areas) show multi-level resistances by combination of their magnetization directions. A four-level operation spin-transfer-torque writing was experimentally demonstrated. scheme for the write/read MLC SPRAM also presented.
Nonvolatile embedded memories may open the door to new computing paradigms based on "normally-off and instant-on" operation. This article covers recent trends of spin-transfer-torque RAM technology, an emerging class nonvolatile memory, discusses its impact different layers computer system hierarchy.
Although species with large area requirements are sometimes used as umbrella species, their general utility conservation tools is uncertain. We surveyed the diversity of birds, butterflies, carabids, and forest-floor plants in forest sites across an (1,600 km2) which we delineated breeding home ranges Northern Goshawk (Accipiter gentilis). tested whether protection could serve effective to protect sympatric four taxa. also empirical habitat model occupancy range examine mechanisms by acts...
One rhesus macaque displayed severe encephalomyelitis and another enterocolitis following infection with molecularly cloned simian immunodeficiency virus (SIV) strain SIVmac239. Little or no free anti-SIV antibody developed in these two macaques, they died relatively quickly (4 to 6 months) after infection. Manifestation of the tissue-specific disease macaques was associated emergence variants high replicative capacity for macrophages primary tissue macrophages. The nature sequence variation...
The power consumption of a low-power system-on-a-chip (SoC) has large impact on the battery life mobile appliances. General SoCs have on-chip SRAMs, which consume proportion whole LSI power. To achieve SoC, we developed embedded SRAM modules, use some techniques. One technique involves expanding write margin; another is power-line-floating technique, enables low-voltage operation. makes it possible to lower minimum operating supply voltage by 100 mV. other techniques involve using...
Abstract Range‐wide genetic variation of the widespread cold‐temperate spruce Picea jezoensis was studied throughout northeast Asia using maternally inherited mitochondrial DNA and paternally chloroplast markers. This study assessed 33 natural populations including three varieties species in Japan, Russia, China, South Korea. We depicted sharp suture zones straits around Japan geographical distribution pattern haplotypes ( G ST = 0.901; N 0.934). In contrast, we detected possible extensive...
We have developed the new "Yin-Yang" feedback technology for SRAM cells. This is applied to six-transistor cells and four-transistor cells, which are composed of transistors with D2G-SOI structure. At 65-nm process node, these can operate at 0.7 V in mass-produced LSIs under real usage conditions. Max operating speeds 300 MHz 200 cell. Leakage current cell about 1/1000 that a conventional These provide menu allows us optimally balance requirements various types low-power LSIs.
We investigated the effect of using a synthetic ferrimagnetic (SyF) free layer in MgO-based magnetic tunnel junctions (MTJs) on current-induced magnetization switching (CIMS), particularly for application to spin-transfer torque random access memory (SPRAM). The employed SyF had Co <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">40</sub> Fe B xmlns:xlink="http://www.w3.org/1999/xlink">20</sub> /Ru/Co and...
This paper describes an investigation of cosmic-ray-induced multicell error behavior in SRAMs. A combination device- and circuit-level simulation was used to show that a parasitic bipolar effect is responsible for such errors, the underlying mechanism what we call battery effect. We have also demonstrated, first time, maximum number cell errors per cosmic-ray strike depends on cells between well taps (Nc). The results are as basis checking correction (ECC) design guideline handling errors....
Although enhancing reserve shape has been suggested as an alternative to enlarging nature reserves, the importance of relative area remains unclear. Here we examined and forest patches species richness, composition, abundance (abundance each species) for 3 taxa (33 birds, 41 butterflies, 91 forest-floor plants) in a fragmented landscape central Hokkaido, northern Japan. We grouped according their potential edge responses (interior-, neutral-, edge-species groups birds plants, woodland-...
Little is known about levels and patterns of genetic diversity for the entire range endangered orchids native to China, Korea, Japan. In this study, we focus on Cypripedium japonicum suggest three hypotheses: 1) that drift has been a primary evolutionary force; 2) populations in central western China harbor higher variation relative those from eastern China; 3) C. maintains highest among countries. Using ISSR SCoT markers, investigated 17 test hypotheses. As anticipated, found low at species...