Study On The Preparation Process And Property Of Diamond-like Carbon Film

With development of science and technology, the property of optical componentsfor infrared optical system is increasing. The optical film is an important part of theinfrared optical element, especially diamond-like carbon (DLC) film for antireflectiveand protective films. The performance of diamond-like carbon film is not only able tomeet the optical property of infrared optical element, but also protect the infrared opticalelement. However, preparation excellent film for infrared optical element must havebeen mastered related preparation process.The purpose of this paper is to master the preparation process of DLC films byradio frequency plasma enhanced chemical vapor deposition and to know the effect ofprocess parameters on the properties of diamond-like carbon films, and then achieve thebest process parameters. The relationship of between process parameters and opticalconstant, the growth rate, structure and micro-hardness of DLC film have been studied，such as the RF power, the deposition pressure, gas flow rate ratio and the distance ofbetween cathode and anode. The main contents of this paper are as following：1. The theory of radio frequency plasma chemical vapor deposition and Coatingequipment are given a brief instruction. The reason of the selection of processparameters was given.2. A computer program for multi-parameter fitting calculations film opticalconstants is compiled. The optical constants of monolayer DLC films deposited underdifferent process parameters are calculated by the program. At the same time, the opticalconstants also obtain by the Ellipsometer. The results from the two measuring methodsare analyzed and compared.3. The relationship between process parameters and optical constant, structureand micro-hardness of DLC film have been studied，such as the RF power, thedeposition pressure, gas flow rate ratio and the distance of between cathode and anode.We obtain the best of process parameter to deposition film. The results show that DLCfilms have a good protection for Si substrate.4. The single-sided and double-sided antireflective and protective films in3~5μm wave band are designed and prepared under the research results. The results show thatdiamond-like carbon film can improve transmittance of substrate.