Funding for MEMS-related research has increased substantially worldwide over the past decade. Funding for MEMS in the United States has expanded significantly, and substantial programs are also known to be underway in Europe, particularly in Germany, Switzerland, and the Netherlands. The Japanese national effort under the Japanese Ministry of International Trade and Industry (MITI), begun in 1991 as a ten-year effort funded at about $250 million, has been the most visible effort globally, and better understanding this program was one important focus for the present study as discussed in Chapter 7. Only a relatively small portion of the MITI program (formally titled the Micromachine Technology Project) involves the development of lithography-based MEMS, which are the principal focus for efforts in the United States. A larger portion of the MITI effort is aimed at the development of micromachines, with the thought that many small machines may someday be able to accomplish tasks currently reserved for a much smaller number of their larger predecessors. The goals are both to develop important technologies for MEMS/micromachines and to identify applications to further guide their development. Table1.2 summarizes some of the important technologies targeted as part of this MITI effort. Many of these technologies, including dry etching and low-temperature wafer bonding, are also targets for development in the United States; however, others, such as microgrinding and electro-discharge machining, have no significant present representation here.
Some Generic Technologies Chosen as the Focus
of the MITI Program in Micromachines
The MITI program has chosen two target systems to guide its efforts during the first five years. The first is an inspection system for the maintenance of cooling tubes in power plants. This system, described in Chapter 7, is composed of four parts: a mother ship capable of traversing the 10 mm main cooling tubes; a wireless microcapsule (no more than 2 mm in diameter) capable of navigating through smaller cooling tubes; a wireless inspection module capable of making detailed analyses of cracks or occlusions in the smaller tubes; and a 2.5 mm OD operation module intended to repair any defects found. A second vehicle is a multilumen active biomedical catheter containing tools for imaging, position control, and microsurgery. The targeted size is in the range of a few millimeters OD. A third project under consideration deals with the development of micromachines to reduce energy consumption in manufacturing and focuses on reducing the size of conventional clean rooms for commercial VLSI wafer fabrication. All of these projects demonstrate the ability of the Japanese to set long-range goals and marshall resources from numerous companies to work cooperatively toward them. They also demonstrate an important approach to the development of a new field such as MEMS, where many of the eventual applications are not yet clear. The Japanese readily admit that none of the projects described above may actually be realized, at least not as currently envisioned. They are merely vehicles for focusing the research. But they involve most of the technologies that are thought to be needed for a broad range of the perceived applications, and it is felt that in the process of working on these systems many useful technologies and products will be spun off. They are an example of the old adage for successful research, "If you don't know exactly what to do, do something!", and are an effective way of focusing resources in an emerging area.
Japanese programs have been significant in the development of sensors, actuators, and MEMS in the past through programs at a number of universities and companies, and the leadership of Japanese industry in consumer products puts them in an excellent position to benefit from MEMS technology. Indeed, the industrial resources being focused on lithography-based sensor development and to some extent on MEMS in Japan are significantly greater than the MITI micromachine program. As in the United States and Europe, however, the total amount being spent on MEMS-related development in Japan is difficult to estimate and remains unknown.