• Atomic diffusion bonding of two flat wafers with thin metal films is a promising process to achieve wafer bonding at room temperature. High surface energies of metal films and a large atomic diffusion coefficient at the grain boundaries and film surfaces enable bonding at room temperature without unusually high loading pressure. This technique, which enables bonding of any mirror-polished wafer, is gaining wider use for fabricating optical and electrical devices. Moreover, bonding of mirror polished metals and polymer sheets can be achieved, which further extends the application of this bonding technique.

Optical, power and electrical devices, MEMS, bonding of polymer sheets, metals, and ceramics for precision mechanical equipments.

• 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.

• Our goal is "bio-inspired engineering" to create new functions that exhibit functions beyond the nature systems by learning from their superior functions and incorporating them into creating materials and devices. For example, the development of surface treatment and adhesives learned from mussels, the development of anti-biofouling substrates learned from pitcher plants, the design of non-platinum catalysts for highly active fuel cells (hydrogen, enzymes, microbes, etc.) learned from hemoglobin, and needle-type biosensors learned from biological needles.

Based on electrochemistry and polymer chemistry, I provide technologies and expertise in the energy, biotechnology, and electrical and electronic fields, including metal-air batteries, fuel cells, surface treatment, adhesion, biosensors, etc.

• 1. Development of Distributed Feedback (DFB) Laser Diodes (LD) widely used in optical communications systems realizing a highly information-based society. This LD increases the transmission capacity by 25,000 times per fiber which means the bit rate of 10Tb/s.
• 2. Nitride semiconductors famous for blue light emitting diodes.
• (a) Proposal of InGaAlN system considering device applications in 1989
• (b) Success in growth of single crystalline InGaN by metalorganic vapor phase epitaxy (MOVPE) in 1989
• (c) Prediction of band-gap energy (Eg) of InN much smaller than the values reported in 1980s and its 　 experimental confirmation in 2002
• (d) Observation of photoluminescence from InGaN in 1991
• (e) Prediction of phase separation in InGaAlN in 1997

DFB-LD: Fabrication of periodic structure with submicron scale, Epitaxial growth of semiconductor films on the substrate with fine structures, LD fabrication process, device evaluation, and device simulation

Nitride Semiconductors: MOVPE growth, N-polar growth, Evaluation of semiconductor materials, Fabrication of light-emitting devices, solar cells, and high-power transistors

• In our laboratory, miniature and highly-functional photonic devices based on new optical phenomena caused by the interaction of ultrafine microstructures with light have been studied. In addition, development of new production technology to overcome the problems that have been obvious from the practical application viewpoint of nanophotonic devices has been performed.
• • -Main research topics--
  MEMS tunable metamaterials for optical control.
• Structural color filters using subwavelength gratings for the applications of display and spectroscopic analyzers.
• Surface-smoothing technology using surface self-diffusion.
• Study of low loss silicon nanophotonic devices.

We aim to realize optical filters, optical resonators, and color filters, by using above technologies. Also, development of nano-photonic elements fabricated by a nanoimprint technology has been progressed.
We hope to conduct collaborative research with a willing company for a practical application of this technology in industry.

• 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.

• The aim of our research are to obtain the high accuracy sensor system for the signals from the human body or electric devices and to obtain the system for approaching action to the human body by using the nano-scale controlled magnetic materials and by the development of the devices under the functions of the magnetics.
• We studied the mechanism of obtaining the magnetic anisotropy of the magnetic thin films for the sensitive magnetic sensors. We obtained a non-metal probe for high frequency magnetic field, and confirmed the probe can measure the high frequency magnetic field with its phase information. In addition, 3D position detecting system using magnetic markers was studied to improve its position accuracy. The study about the magnetic actuator driven by the external magnetic field was carried out for biomimetic robots using the rotational magnetic field, and small wireless pumps were obtained and clarified for their application for an artificial heart-support pump.

<Medical Applications>
Motion system for capsule endoscope, Support system for endoscopic surgery, Position detecting system (motion capture), Wireless pump for artificial heart
<Sensors>
Magnetic field sensors, Strain sensors, Wireless sensors
<Materials>
Electrical steels of ultra low loss, Electrochemicaly produced materials (structure controlled in nano-scale)

• In our laboratory, miniature and highly-functional photonic devices based on new optical phenomena caused by the interaction of ultrafine microstructures with light have been studied. In addition, development of new production technology to overcome the problems that have been obvious from the practical application viewpoint of nanophotonic devices has been performed.
• • -Main research topics--
  MEMS tunable metamaterials for optical control.
• Structural color filters using subwavelength gratings for the applications of display and spectroscopic analyzers.
• Surface-smoothing technology using surface self-diffusion.
• Study of low loss silicon nanophotonic devices.

We aim to realize optical filters, optical resonators, and color filters, by using above technologies. Also, development of nano-photonic elements fabricated by a nanoimprint technology has been progressed.
We hope to conduct collaborative research with a willing company for a practical application of this technology in industry.

We offer shared facility for the development of semiconductor prototypes equipped with 4-inch, 6-inch and some 8-inch wafer fabrication tools available on an hourly basis. Know-how accumulated at Tohoku University is available, and staff provide maximum support for prototyping. The service is performed at the 1,200 m2 Super Clean Room on the second floor of the Junichi Nishizawa Memorial Research Centre at Tohoku University. For information on equipment and fees, see our website.

More than 10 experienced technical staff assist customer's usages. Standard process conditions for each process, such as etching and deposition, are provided. allowing customers to start prototyping immediately. Various materials other than silicon can also be supported.

• We support the development of devices and semiconductor materials such as MEMS, optical elements and RF components.
• Technical consultation on devices and processes before and during prototyping is also available.
• A
• 'Prototype lab' for device packaging is also available.
• The museums where you can learn about the history of semiconductors, measuring instruments and sensors are open.
• As part of Technology Co-creation for Semiconductor of Tohoku University, we promote R&D of semiconductors and the development of human resources.
• On-demand semiconductor human resource development programs for students and engineers are available.
• As a member of the MEXT's Advanced Research Infrastructure for Materials (ARIM) program, we are involved in sharing facility and data.

More than 330 companies have used our shared facility since its launch in 2010, not only from device manufacturers such as MEMS, but also from manufacturers of materials, mechanical components and equipment. To date, we have successfully supported the commercialization of about 10 devices.

• 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.

• 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.