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Creation of Perfect Surface


To establish an excellent technology of ultra-smooth surface machining as a foundation of frontier technology and basic science

1. Project Outline


Perfect surfaces with the structure controlled at the atomic level are inevitably required not only in the development of frontier technology for industry that supports the future of Japan, but also in the basic research which challenge the root of natural sciences. For instance, it is supposed in the field of frontier technology that even atomic size roughness on the silicon wafer can not be allowed for next-generation semiconductor devices, because even slight surface roughness will affect the performance of devices. In order to achieve the precision machining for this type of semiconductor, it is necessary to use the light sources with very short wave length such as excimer laser and synchrotron radiation. The development of optical components requires suitable lenses and mirrors for these types of light sources. The laser in the ultraviolet region is inspiring efforts to develop lenses with an extremely smooth aspheric surface. The radiation in the soft X-ray region necessitates attempts to develop a toroidal mirror with ultra precision shape that is smooth at the atomic level. In addition, the necessity of ultra precision machining to produce the perfect surfaces is growing in the field of basic natural sciences, in order to make mirrors of astronomical telescopes to search for the origins of the universe and those of cavity resonator to detect gravity wave which lately has been stirring so much attention in the field of gravity wave astronomy.
The goal of our research project is to establish technology of ultra precision machining capable of creating ultra-smooth surfaces at the atomic level with extremely high precision in any shape. At the same time, we aim to develop technology capable of evaluating these created surfaces at the atomic and electronic levels. Depending on the conventional mechanical machining , we might fail to realize such high precision, and so it is indispensable to develop an epoch-making technology for ultra precision machining based on a new concept. Our research group has been developing technology for the creation of ultra-smooth surface by means of atomic processes of chemical reaction under the guidance of the group leader, such as EEM (Elastic Emission Machining) and plasma CVM (Chemical Vaporization Machining). EEM is a chemical machining with utilizing activities of surface of powder particles, which has a great potentiality to create perfect surfaces. Plasma CVM is also a chemical machining with utilizing reactive radicals in plasma gases under the atmospheric pressure, which is very effective to produce smooth surfaces at high removal rate. We succeeded in making mirrors of laser gyroscope for adjusting the position of H2-type rocket by EEM technology, and also in making mirrors used for reforming a beam shape of laser for the uranium isotope separation by plasma CVM. It is intended, therefore, to push on with these research themes and to establish systematized technology of ultra precision machining as a new paradigm of natural science.
In order to fulfill these objectives, we shall found the research center that combines systematically the following four schemes through invention of ultra precision machining equipment and we shall promote the research in each area of these four schemes.
In the area of new machining process, we are investigating the possibility of electrochemical machining by means ofultra-pure water besides EEM and plasma CVM. As to theoretical approach to the machining mechanism, we have been carrying out very large-scale simulations using programs of first-principles molecular-dynamics method developed by ourselves. For measurement and control of machining process, we are analyzing a structure of high-pressure plasma to control the machining process. For evaluation of machined surfaces, we are now not only performing conventional STM/STS and optical measurements but also developing new methods, such as the hybrid STM to which a function of Auger electron spectroscopy and/or X-ray spectroscopy is added, the scanning near-field optical microscope which has received so much attention recently, and so on.
In order to achieve the goal, we shall found the Ultra Precision Machining Research Center at Osaka University as illustrated in the following schema and take the initiative in the world as COE towards the development of machining processes and the scientific systematization of ultra precision machining.
www-admin @prec.eng.osaka-u.ac.jp
Last revised on Jul. 8, 2001 by M. Nakano