Currently widely used machining methods such as cutting, grinding, polishing, etc., due to the existence of micro-cracks in the processed materials or the quality defects in the crystallization, no matter how to improve the machining accuracy and improve the machining equipment, there are always certain limitations. Professor Mori Yongzheng, Faculty of Engineering, Osaka University, Japan, proposed a new processing method using chemical gas, called plasma CVM method, which is a technology that uses atomic chemical reactions to obtain ultra-precise surfaces. Its processing principle Like plasma etching, in the plasma, the activated free radicals react with the surface of the workpiece, turning them into volatile molecules, and the processing is realized by gas evaporation, and the plasma is generated under high pressure. , able to generate very high densities
free radicals, so this processing method can achieve processing speeds comparable to mechanical processing methods.
At high pressures, the plasma is confined near the electrodes due to the extremely small mean free path of the gas molecules. So it can be processed by electrode scanning, O. Parts of any shape with a precision of 01μm can also process a single crystal silicon plane at a speed of 50μm/min, and the surface roughness of the processed workpiece can reach 0.1nm (Rrms).
In the next century, CVM technology will be applied in many fields such as silicon chip processing and aspheric lens processing for semiconductor exposure devices. Currently, some people are studying the combination of CVM and EEM to process atoms such as X-ray mirrors for synchrotrons. A flat arbitrary surface.