Site: Tohoku Gakuin University
Department of Electrical Engineering
13-1 Chuo-1, Tagajo
Miyagi-ken 985, Japan

Date Visited:

Report Author: S. Jacobsen



H. Guckel
S. Jacobsen
L. Salmon
K. Wise


Dr. Mitsutera Kimura Tohoku Gakuin University
Dr. Masayoshi Esashi Tohoku - Sendai
Mrs. Cleopatra Cabuz Tohoku - Sendai
Dr. Seung-Ki Lee Tohoku - Sendai


Dr. Mitsutera Kimura has no permanent staff and uses student workers in the laboratory. He has stated that funds and lack of staff are a handicap to his progress. Despite these limitations, Dr. Kimura's laboratory is well laid out and very clean given that it is still in development. Most of the equipment has been donated, but seems to serve his needs for the present.

Dr. Kimura's laboratory mostly focuses on the development of microcircuits, which include some micromachining. The goals of the laboratory include education, technology development, and development of products intended to be spun off to commercial ventures. Eleven projects were discussed.

Dr. Kimura's Projects

1. Silicon etched wave guide (1980)

This work focussed on the generation of optical wave guides on both sides of a groove etched in silicon. This method was also mentioned in relation to generating microair bridges.

2. Miniature optoelectric transformer

The miniature optoelectric transformer concept included a solar cell, an electrical transformer, and a laser diode emitter integrated onto a single silicon chip.

The photocell was configured for direct interaction with a core of optical fiber. The geometry included a toroidal depression with a raised center appropriate for docking with the fiber core.

The transformer included a two-turn primary and a two-turn secondary (a later design will include a many-turn secondary). Dr. Kimura claimed an interesting method for deep etching to form the coils.

The laser diode emitter was designed, but a real system has not been fabricated or tested. Specific applications were not identified nor has a complete system been fabricated.

3. Schottky tunneling transistor

Dr. Kimura claimed to have achieved very low threshold devices (i.e., no power drop), which could be very good for solid state relays and other devices.

4. Field emission vacuum magnetic field sensor

A system was discussed that measures the local magnetic field by detecting the magnetically induced deflection of an electron stream. The concept was very interesting; however, with deeper examination, the JTEC team had serious questions regarding its practicality. The system required very large electric field gradients (20 kV per cm), and the use of Dr. Kimura's special zero threshold transistor.

5. Microheater made of heavily boron-doped single crystal silicon beam (1981)

6. Schottky barrier thermistor

7. Infrared sensor with microair bridges of a-Si(h) film

8. Anemometer-based flow sensor

9. Vacuum sensor

10. Humidity sensor

11. Accurate compensation method for the ambient-temperature-dependent deviation of thermistors

Dr. Kimura has focused on developments that have commercial markets. He patents his work and collaborates with industrial groups to commercialize results. Dr. Kimura indicated that in Japan, professors are free to execute patents independently of the university and to arrange for industrial contracts that commercialize products and pay royalties directly to the professors.

Published: September 1994; WTEC Hyper-Librarian