Development and its commercialization of the lithium-ion battery

Akira Yoshino
Fellow of Asahi Kasei Corp.

Reason for award

In the development process of mobile devices such as mobile phones and notebook personal computers which have been explosively widespread throughout the world, development of a compact, lightweight, high-capacity rechargeable battery (secondary battery) has been eagerly expected at all times. In 1985, Akira Yoshino solved the problem of the conventional secondary battery and established the fundamental concept of the lithium-ion battery that are widely diffused nowadays.
The conventional secondary battery using an aqueous electrolyte had lower electromotive force, leading to a limitation in large capacity. Although a secondary battery using metallic lithium for electrodes with a non-aqueous electrolyte was expected for large capacity, its practical use was not achieved because of problems of safety and degradation.
Yoshino established the fundamental concept of the current lithium-ion battery by using lithium cobaltite (LiCoO₂) whose possibility as an effective electrode material had been already found at the beginning of the 1980s for the positive electrode, and a carbon material instead of conventional metallic lithium for the negative electrode.
In addition, Yoshino developed all kinds of component technologies such as a charge collector and a separator constituting a battery, which realized practical use of the lithium-ion battery at the beginning of the 1990s.
The current market share exceeding one trillion yen could not be explained without the fundamental concept Yoshino developed and its impact on the society is immeasurable.
For the above reason, Akira Yoshino shall be awarded the 11th Yamazaki-Teiichi Prize in Material.

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Invention and development of "fin" structure MOSFETs

Digh Hisamoto
Chief Researcher of Electronics Research Center, Central Research Laboratory, Hitachi, Ltd.

Reason for award

Digh Hisamoto invented the world's first three dimensional fin structure MOSFET (originally named DELTA) to solve the problems related to size reduction of MOSFETs which were being revealed in the second half of the 1980s, demonstrated its effect by fabricating devices with gate length of about 300 nm for trial, and presented it at IEDM (International Electron Devices Meeting) in 1989. Since this structure can suppress the variation in the threshold voltage and the leak current due to the short channel effect of the MOSFET, and furthermore is possible to increase the driving current by increasing the height of the fin, it is suitable for size and voltage reduction. Subsequently, he developed MOSFETs with gate length of 17 nm through the joint research with University of California, Berkeley (UCB), demonstrating possibility of size reduction, and he presented it at IEDM in 1998. Today, the structure is broadly called FinFET representing its shape well.
While the mood for utilization of fin structure MOSFET including LSI (DRAM) for memory has been growing in these years, a logic LSI (MPU) manufacturer has announced that they would commercialize the technology (in the second half of 2011) very recently. These movements indicate that the plane structure MOSFET used over the past 40 years is at a turning point changing into a three-dimensional structure. With the fin structure MOSFET invented and developed by Hisamoto, the size of MOSFET will be reduced continuously henceforth, thus, its contribution to the development of the semiconductor industry is very significant. The research result is very excellent in originality and foresight as well as impact on the industry.
For the above reason, Digh Hisamoto shall be awarded the 11th Yamazaki-Teiichi Prize in Semiconductor & Semiconductor Devices.

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Development and application of spin-polarized low energy electron microscope
for dynamic observation of magnetic domains

Tutomu Nakanishi
Professor Emeritus at Department of Physics,
Graduate School of Science, Nagoya University

Yoshikazu Takeda
Professor at Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University

Takanori Koshikawa
Director and Professor at Fundamental Electronics Research Institute, Osaka Electro-Communication University

Reason for award

In 2007, A. Fert and P. Grunberg were awarded the Nobel Prize in Physics for the discovery of the giant magnetoresistance (GMR) effect since they exploited a very new "spintronics" field. However, the measurement science and technology necessary for engineering development in this field was not sufficiently prepared.
Three researchers, Nakanishi, Takeda and Koshikawa succeeded in developing a spin-polarized low energy electron microscope enabling real time observation for understanding details of development of magnetic domain that is important for the development of a thin film magnetic material.
With different specialties, they cooperated closely and developed a high-performance spin-polarized electron gun first in the world. The performance was significantly improved in comparison with that of the conventional one, i.e., increased brightness by 10,000 times or more, increased spin polarization from 20% to 90%, and the elongated lifetime of the cathode from current mere 3 or 4 hours to about 2 months. As a result, the acquisition time of the magnetic domain image on a solid surface was reduced to 20 ms / frame equivalent to 1/200 of the current value.
They performed dynamic observation of the magnetizing property of a [CoNi₂]_y multi-layer film in a growth process using the device and found that the stable magnetic property was achieved with only 4 layers. In addition, they obtained a good international reputation with new findings such as that a [CoNi₂] / W (110) film showing an in-plane magnetization property would change to a vertical magnetization status only by vapor-depositing Au of only one-atom layer.
As above, Nakanishi, Takeda and Koshikawa have developed and applied the high-performance spin-polarized low energy electron microscope which enables real time observation necessary for development of new magnetic device, magnetic film materials and the like, thus they shall be awarded the 11th Yamazaki-Teiichi Prize in Measurement Science & Technology.

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Development of a crystallization method utilizing phospholipids and elucidation of the mechanism of calcium pump

Chikashi Toyoshima
Professor of Institute of Molecular and Cellular Biosciences, the University of Tokyo

Reason for award

Chikashi Toyoshima has conducted structural analyses of a protein called calcium pump, which is essential to biological activity, almost all by himself. The protein transports calcium ions across biological membrane. He elucidated the atomic structures of the protein in all 4 principal states that constitute the reaction cycle, and determined 8 crystal structures in total including its intermediate (transition) states. This is the first in the world that the path of the structural change of a protein, including water soluble and membrane proteins, has been shown in such details.
The key to success was to stabilize the intermediates by controlling the state of the membrane protein precisely during crystallization. His success in determining even the intermediate structures, with various ideas free from the established methodology, for example, addition of phospholipid contrary to common practice, delicate control of conditions and sample compositions throughout the crystallization process, encourages and provides driving force for following researchers, and contributes to the development of calcium pump research based on his results.
Many important physiological functions are conducted by membrane proteins, which are important targets of drug discovery as well. As analyses of their functions and structures progressed only very slowly, the achievement by Toyoshima who solved the most difficult problem has been recognized internationally. With Toyoshima's research results and research methods, we can expect further great and rapid development in this field in near future. The elucidation of the atomic structures of all 4 principal states and the determination of the 8 crystal structures in total including their intermediate (transition) states may lead to future drug development for each intermediate, posing major impact on the whole drug development research.
For the above reason, Chikashi Toyoshima shall be awarded the 11th Yamazaki-Teiichi Prize in Biological Science & Technology.

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