Study On Ion Beam Deposition Correction Polishing Of Super Smooth Pptical Element

Super smooth optical element is demanded to have low scattering rate and roughness of the surface and ensure the integrity of the surface lattice, in order to achieve the purpose of high reflection. Because of the limitation of the existing processing method, it is difficult to meet the requirements of processing ultra smooth surface. As a new surface machining method, ion beam deposition correction polishing technology can obtain a lower surface roughness. Otherwise, the workpiece surface and subsurface can not be damaged after processing. This paper introduced the design and machining process of the ion beam deposition correction polishing system. The problems existing in the polishing process were discussed and the ion beam deposition correction polishing technology was studied preliminarily.The ion beam deposition correction polishing system was introduced in this paper in order to study the experiment of related technology of ion beam deposition correction polishing. The system included planarization reflow process and ion beam etching polishing process. The paper studied planarization reflow process mainly, and the planarization reflow device was designed, which included bubble generator, fluid flow control system, mixing chamber and sealed sample room. The collection of planarization reflow material of ion beam etching polishing process and the planarization preparation technology were discussed. Besides, the best process parameters of organic thin film surface polishing was obtained by the experiment of planarization reflow on ZnS crystal surface to reduce the roughness of ZnS crystal surface. Finally, the ZnS crystals cut by single point diamond were polished by ion beam deposition correction polishing technology.The experimental results show that:(1) In the ion beam deposition correction polishing technology photoresist EPG533was collected as the planarization reflow material;(2)In planarization reflow process.gas flow of the planarization reflow device got command of (0.4ml/min,0.4ml/min) while the ventilation time was8min.Heat treatment methods adopted combination of before and after, and this way can effectively reduce the roughness of EPG533photoresist film surface.(3) In ion beam etching process adopted a high vacuum pressure of5×10-4Pa, working pressure of5.0×10-2Pa, Ar gas flow rate for11Sccm, Ion beam energy for400v,Ion beam30mA,processing Angle of40°.Under the process parameters synchronous etching EPG533photoresist film and ZnS crystals obtained approximately to achieve the effect of polishing.