Profile Analysis And Experimental Study Of Hard And Brittle Crystal Thin Substrate In Lapping Process

With the development of technology,higher and higher profile accuracy and surface quality for the thin substrate of hard and brittle crystal are required,such as laser crystal,engineering ceramics and quartz crystal.Taking the development of laser technology as an example,in the development course of laser technology,thin-layer laser is considered to be one of the most important milestones.Based on the design concept of solid-state laser,it puts forward an innovative structure.With the advantages of small size,high efficiency,good beam quality and high stability,thin-layer laser has attracted much attention and become the main research direction of high-power laser.As the core component of thin-layer laser,laser crystal thin substrate has a decisive influence on the output characteristics and the actual output power of the thin-layer laser.However,in the process of machining,it is difficult to meet the requirements of profile accuracy and surface quality because of the high hardness,thin thickness and large aspect ratio of the hard and brittle crystal thin substrate.For the difficulties of profile accuracy in the lapping process,this paper mainly studies on the two aspects,these respectively are the material removal uniformity of the hard and brittle crystal thin substrate and the holding methods in lapping process.The main research contents include:(1)Material removal uniformity of the hard and brittle crystal thin substrate in lapping process.The relationship between the substrate and the lapping disc was analyzed,and models of the relative velocity between the substrate and the lapping disc,the trajectories of the particle on the substrate were established.The influence of processing parameters on the velocity and the uniformity of the trajectories were analyzed.With the optimization target of consistent uniformity of the speed and the density of the particle trajectories on the substrate,this paper aims at providing a theoretical reference for the optimization of the processing parameters in the lapping process of hard and brittle crystal thin substrate.(2)Influence of holding methods on the profile of hard and brittle crystal thin substrate.A set of vacuum jig system and vacuum holding clamping force measurement device were designed and the performance of the vacuum jig was proved.The profiles of crystal thin substrates under different vacuum adsorption conditions were compared.The profiles of the crystal thin substrates were compared under different paraffin bonding conditions.(3)Experimental study on the profile of hard and brittle crystal thin substrate in lapping process.The influences of rotating speed on the profile of hard and brittle crystal thin substrate in lapping process were studied respectively with vacuum adsorption and paraffin bonding.The profile of crystal thin substrate were compared with vacuum adsorption and paraffin bonding.