• Micro and nano electro-mechanical systems (MEMS/NEMS) have completely changed human society in the past decades. Many devices that are taken for granted these days like smart phone, future car and drone would be unthinkable without them.
• The integration of various new kinds of materials, such as metallic glass and nanostructures into micro technologies allows us to create devices with novel performance and characteristics; examples include acoustic sensors and actuators, thermoelectric generators and wafer level packages.
• In collaboration with partners inside and outside Tohoku University, technologies are being developed that can be transferred to industry ranging from material integration and processes to packaging and reliability.

Wide collaboration in Microsystem technology is possible. We develop, implement and optimize processes, devices and systems until they are ready for use, keeping in mind reliability, yield and other important features for commercialization. We work with also with partners, such as Fraunhofer. Flexible interlinking of expertise and capacities with other research groups enables us to meet broad project requirements and create complex system solutions.

• We are studying MEMS (Micro Electro Mechanical Systems) and related technologies, which are typically used for the input/output of information/communication devices, the safety of automobiles etc. Our representative topics include integrated sensors, piezoelectric devices, RF MEMS, micro energy devices and wafer-level packages. Our facilities are open-accessible and well equipped with a lot of tools for lithography, dry/wet etching, thin film deposition, wafer bonding, device mounting and evaluations, which can be operated by each researcher. Using these tools, a variety of MEMS are being prototyped. Also, new microfabrication tools are being developed by ourselves.

We are collaborating with many companies, from which visiting researchers are dispatched to our laboratory. We also accept companies which want to just use specific tools in our facilities. Consultation is always welcome.

• Scanning tunneling microscope (STM) and atomic force microscope (AFM) are among a few microscopes which enable a direct observation of atomic scale structures of materials. If compared with other electron microscope like transmission electron microscope (TEM), the energy of the electron used for STM is very low that has a big advantage of low damage for sample. Thus STM and AFM are regarded as the most important tools to characterize materials in nanotechnology. The research is now developing from a mere observation of the shape of material to the characterization specific properties of materials with an atomic scale resolution. These properties include spin and molecule vibration; well established techniques like ESR/NMR and infrared-spectroscopy requires more than billions of molecules to obtain data, while STM can obtain these data for a single molecule.
• We are interested following issues and like to have a collaboration with industrial companies.
• 1. Molecule-scale morphological characterization of soft-material, polymers and bio material.
• 2. Site specific vibration spectroscopy of molecules with an atomic resolution.
• 3. Single spin detection with ESR-STM method
• 4. Developing atom-scale characterization tool

• It is well known that nano-scale impurity/solute clusters, defects, defect clusters and their complexes affect the mechanical and electrical properties in materials. However, it is very difficult to observe these objects even by state-of-the-art electron microscopes. We overcome the difficulty by employing noble two techniques: laser three-dimensional atom probe (3D-AP) technique and positron annihilation spectroscopy (PAS). Laser 3D-AP can map out each atom in various materials (metals, semiconductors, insulators) in three-dimensional real space with nearly atomic scale resolution. PAS can detect vacancy-type defects and defect-impurity complexes very sensitively.

By combining these methods, we are going to reveal the functions of the fine impurity clusters and defects to the materials: developments of new nano-structured materials, the mechanism of degradation of aged structural materials, the fall in the yield of semiconductor device production, and developments of quantum devices etc.

• Microstructure represents various kinds of heterogeneities in the metallic materials, i.e., grains, component phase, lattice defects and chemical inhomogeneity such as impurity/alloying elements. It can be modified through control of phase transformation/precipitation and deformation/recrystallization by adjusting compositions of materials and/or through processing routes (heat treatment, deformation). Such expertise in micro/nanostructure control is very important in production of current materials from viewpoints of energy saving and recycling in structural materials such as steels and titanium alloys.
• We attempt to apply more advanced control of micro/nanostructures, such as atomic structures of crystalline interfaces, chemistory in an atomic scale (e.g., segregation) and so on. Fundamentals of microstructure formation (thermodynamics, kinetics, crystallography) are examined both theoretically and experimentally to clarify key factors for microstructure control. Another important aspect in our research is the improvement of mechanical property by microstructure manipulation.

Possibilities to establish new functions (e.g., superplasticity, shape memory/superelasticity) as well as superior mechanical properties (e.g., ultrahigh strength with high toughness/ductility) is also explored.

• Microwave processing is one of the attractive fields in recent materials processing. We perform various materials processing using non-equilibrium reaction field induced by microwave and/or ultrasonic irradiation. The topic contains powder metallurgy, nitride coatings, synthesis of new functional materials, fabrication of nanoparticles, etc. Recently we have developed a new TiN coating method using our microwave irradiation equipment operated at a frequency of 2.45 GHz. The method is simple but applicable to various substrates with complex shape. This method can be applied to various nitride coatings and will open a new coating technology in many fields of applications.

The major targets of TiN coatings are for cutting tools, ball bearings, dental implants, die and mold for stamping, and ornaments. The newly developed method makes it possible to perform nitride coatings within a short time using a standard microwave heating equipment. We hope to conduct collaborative research with a willing company for a practical application of these technology.

• We are developing a non-destructive testing method for the long range rapid inspection of metallic pipe using microwaves. The method propagates a microwave inside a pipe, and evaluates flaws appearing at the inner surface of the pipe on the basis of the reflection and transmission of the microwave. The method does not require scanning probes unlike conventional non-destructive methods, which enables one to inspect a pipe quite quickly. Our experimental validations have demonstrated the effectiveness of the method using a pipe as long as 30 m.

The NDT method proposed here is applicable when many pipes are inspected or conventional methods are not available due to pipe length and its configuration.

• The objectives of my researches are the development of high performance magnets and improvement of their magnetic properties. I have already developed following high performance magnets, such as Nd-Fe-B magnets using didymium, Sm-Fe-N high coercive powders prepared by HDDR and Fe-Cr-Co magnets. Recently, I have studied about the reduction of Dy content in Nd-Fe-B magnets for the use of HEV and have succeeded to develop high coercive Dy-free Nd-Fe-B sintered magnets by decreasing the grain size. I have also developed new kinds of microwave absorbers for the use in the frequencies of GHz range using permanent magnetic materials or nanoparticles.

High performance magnetic materials can be used in many applications in automobile, home electronics, IT and medical industries. We hope to conduct collaborative researches with companies producing magnetic materials for the use in these applications, which aims to improve magnetic properties or to develop new magnetic materials.

• We successfully realized millisecond-order X-ray phase tomography using a fringe-scanning method in grating-based X-ray interferometry. We obtained phase tomograms with a measurement time of 4.43 ms using a white synchrotron X-ray beam. The use of a fringe-scanning method enables us to achieve not only a higher spatial resolution but also a higher signal-to-noise ratio than that attained by the Fourier transform method. In addition, our approach can be applied to realize four-dimensional or high-throughput X-ray tomography for samples that can be rotated at a high speed.