SUMMARY AND CONCLUSIONS

MEMS-based sensor technology capabilities in Japanese and U.S. industrial laboratories appear largely comparable in quality and state of the art, and in technology and applications focus. There are major efforts on both bulk and surface micromachined devices, on the use of wafer bonding for integrated sensor packaging, and on integration of electronic circuitry with sensors. Both emphasize high-volume applications, such as automotive, and important sensors, such as pressure and accelerometers. High performance devices such as precision pressure sensors are under development in both countries. MEMS-based development of a variety of more complex sensors driven by military applications is relatively strong in the United States, but there is no equivalent effort in Japan.

The United States generally appears to have a lead in demonstration of innovative new materials and process technologies for MEMS-based sensors, and in the first demonstration and commercialization of new device concepts. Much of this lead derives from innovative research at U.S. universities, and from entrepreneurial start-up companies.

MEMS sensor R&D at U.S. universities is a major area of strength compared to Japan. The top U.S. universities in sensor research -- including Berkeley, Michigan, MIT, Wisconsin, and others -- are superior to those in Japan, with the exception of Tohoku University. This superiority exists in the quality of the facilities, the breadth of capabilities in both microfabrication and testing, and the critical mass of students and faculty. There is a vast array of technology under development in U.S. universities, where students are receiving excellent training. If this technology is appropriately focused on high-payoff applications and transferred in a timely and cost-effective manner, it can provide major technological advantages for U.S. industry.

MEMS-based sensors are being commercialized in the U.S. by companies in the sensor component, electronic component, and systems businesses. U.S. industry appears to be producing more innovative sensor technologies and commercial sensor products somewhat earlier than Japan. The presence of many innovative, entrepreneurial sensor start-ups has driven the commercialization of solid-state sensor technology in the United States, and is a major difference between the United States and Japan. Examples of these smaller, high-technology sensor companies include NovaSensor and IC Sensors. They have produced basic technology innovations such as silicon fusion bonding, have driven the costs down for high volume products such as medical pressure sensors, and have been responsible for the first commercial introductions of a variety of new MEMS-based sensors. Their presence creates a competitive and innovative environment, and probably also forces larger companies in the United States to commercialize more rapidly. No equivalent entrepreneurial start-ups exist in Japan, and this may be partly responsible for an apparently slower pace of innovation and commercialization there.

In summary, the U.S. MEMS sensor technology base is, in general, comparable to that of Japan and somewhat ahead in development of new processes and new device concepts. This technology base does not appear to be a limiting factor in U.S. competitiveness now or in the foreseeable future. U.S. advantages include superior university research, and competition and innovation in the marketplace. However, Japanese MEMS sensor technology capability is strong, and certainly not far behind that of the United States. Japanese development efforts are focused on the most important commercial applications. Japanese companies now have and will continue to have products to market in time to meet the most important application opportunities. Success in business based on MEMS sensor technology will be greatly dependent on the vision, strategic planning, and investment decisions of industry, and on the ability to appropriately and cost-effectively commercialize this technology into innovative products in a timely fashion.

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Published: September 1994; WTEC Hyper-Librarian