Nonotechnology - Its Seeds and Initiative
Kenichi Iga
Japan Society for the Promotion of Science (JSPS)
Background
Leading technology that was an antecedent to current nanotechnology progress may have been two vertical devices invented in 1977, i. e., the vertical cavity surface emitting laser (VCSEL) [1][2], and perpendicular magnetic storage disk[3]. In the National Nanotechnology Initiative (NNI) of the US government, the VCSEL was featured together with a high electron mobility transistor (HEMT) as examples of early nanotechnology[4]. When we trace the headwaters of nanotechnology concept, it is said we find Feynman's lecture in 1959[5]. Subsequently, K. Drexler wrote a book in 1986 entitled "Engines of Creation: The coming Era of Nanotechnology," in which he promoted nanosystems[6]. On the other hand, R. E. Smalley stands rather against the straight forward pursuit of this path[7].
The NNI was started in around 1998 as an action plan for reinforcing US industries. In 2001, the Japanese Science and Policy Council implemented a plan for promoting of science and technology by identifying 4 important areas including nanotechnology, IT, lifescience, and environmental technologies. Nanotechnology is the linchpin tying the other 3 areas together.
Nano Science and Technology - Seeds
The attached table, prepared by the author independent of national projects, may be used to locate nanotechnology seeds. Some of them are already being considered at industrial levels, but most still require basic research. It is expected that the market for nonotechnology in Japan may reach 2.4 trillion yen by 2005.
Nanotechnology in Photonics
The author invented the VCSEL mentioned above[1] and has continued to conduct basic research toward its realization. Its concept is based upon a fully monolithic fabrication of semiconductor laser devices utilizing a kind of nanotechnology. It took more than ten years before room temperature continuous operation was achieved in 1988. This was primarily due to a need to advance the research in parallel with advances in process technology. However the work gave form to a concept of "micro-laser," ultimately allowing low current operation, i. e., of about 100 microamperes, which is two orders of magnitude smaller than conventional stripe lasers. Since 1999, the VCSEL has been mass-produced as light sources for Gigabit Ethernet and highspeed networks. More recently, long wavelength VCSELs are being considered as lasers for highend lightwave systems by incorporating sophisticated nano and MEMS technologies into device sub-systems.
Photonics and electron devices, such as semiconductor lasers and HEMTs, are equipped with nano-scale components to exhibit various quantum effects, as nano-scale is the size of electron wave packets in semiconductors. Quantum wells, wires, and dots have been introduced into semiconductor lasers to produce excellent lasing performances. Super-lattices can be used for electronic wave interference in resonant tunneling diodes.
Prospects
Nanotechnology is not necessarily a problem of scaling, but is rather an issue of concept. The nano order is positioned at a rather intermediate region of dimension, i. e., larger than the atomic scale and smaller than the real world. It can provide some very important physics for the macroscopic world through quantum effect, for instance. Material and structure used to be considered as independent, but now nanotechnology plays an important role in bridging the material and device.
References
[1] K. Iga, Lab. Note, March 22, 1977.
[2] H. Soda, Y. Suematsu, C. Kitahara, and K. Iga, Jpn J. Applied Phys., 18 p.2329 1979.
[3] S. Iwasaki, Invention in 1977.
[4] M. Roukes, http://physicsweb.org/article/world/14/2/8.
[5] HP of NNI, Appendix B10, p.77 2000.
[6] K. E. Drexler, "Engines of Creation: The coming Era of Nanotechnology", John Brockman Associates Inc. New York, 1986.
[7] R. E. Smalley, Scientfic American, 2001.(cf: http://cnst.rice.edu/reshome.html).