FEM Analysis And Experimental Research On The Technique Of Ultrasonic Flexural Vibration Assisted Lapping/Polishing Of Hard And Brittle Materials

Nowadays, integrated circuits have been on the way to the development of a verylarge scale integration, ultra-high frequency and higher performance with the rapiddevelopment of science and technology, especially the improving of the information andcommunication level. Semiconductor materials are the key core of integrated circuit. Theyplayed a key role in the electronics industry and they are also a key link in the developmentof the electronic information. At the same time, a number of semiconductor materials arealso important optical materials and used in the manufacture of optical element whichplays a very important role in the areas such as military, aerospace and space exploration.However, most of semiconductor materials belong to hard and brittle materials, and thiskind of materials puts forward higher request to process. For example, the manufacturingprocess is not stable, finished materials’ surface quality is not high, machining efficiency isvery low and it is hard to realize the mass production on a large scale, etc. To solve thesedifficulties to manufacture the hard brittle material with high quality in production, thetechnology of lapping and polishing has been developed.The technology of lapping and polishing is the last two manufacturing processes ofsingle-crystal silicon. Lapping is aimed to cut off the micro bulge on the surface of thesingle-crystal silicon quickly, and then keep its surface flat. Polishing is aimed to makesingle-crystal silicon’s surface roughness down, and make the surface smooth. At the sametime, polishing also reduces surface and subsurface damage caused by manufacturingprocess. To make the most use of electronic products, the technology of lapping andpolishing which is important to single-crystal silicon is developing very fast. However, theprocessing mechanism of lapping and polishing is complex. So the material removalmechanism and process parameters optimization also need to be researched. In this paper,FEM analysis and experimental research on the technique of ultrasonic flexural vibrationassisted lapping and polishing are used to understand the influence on the effect of lappingand polishing under different process parameters. And then the material removalmechanism has been analyzed under the condition of ultrasonic vibration.Firstly, the research background and significance of the technology of lapping andpolishing are introduced. And the present research status of the technology of lapping and polishing is introduced systematically based on theoretical model research and processimprovement at home and abroad. As the value of research on the ultrasonic vibrationassisted lapping and polishing process is proved to be significant by comparing withconventional machine tools, it turns out the research point on the ultrasonic vibrationassisted lapping and polishing process.In this paper, the lapping and polishing machine tool under ultrasonic vibration istransformed from conventional machine. The research equipment and test device areintroduced systematically. The test process and matters needing attention during lappingand polishing process are made due to practical operational steps. The detailed testing planis made based on the influence of lapping and polishing process parameters. And then testmaterials and reagents are introduced based on testing plan.The experimental research on the technique of ultrasonic flexural vibration assistedlapping and polishing is carried out by lapping and polishing single-crystal silicon.Lapping and polishing tests are carried out under different manufacturing processparameters. The influence of different lapping and polishing process parameters onmaterial removal rate (MRR) and surface roughness is discussed due to the test data afterlapping and polishing. Compared with conventional and ultrasonic flexural vibrationassisted manufacturing, the material removal mechanisms of lapping and polishing processare discussed and the material removal mechanisms of ultrasonic flexural vibration areanalyzed.On the basis of the above work, A simplified three dimensional finite element modelof lapping and polishing process is developed by using the explicit software ABAQUS toresearch the manufacturing process. And material removal mechanism and deformationdamage are researched by use of the finite element model. According to the result ofsimulation, the influence of different lapping and polishing process parameters on themorphology of processed material, residual stress and material removal rate is discussed.Based on the finite element simulation and experimental research, the influence ofprocess parameters during lapping and polishing process is researched. The manufacturingmethods are improved assisted by the technique of Ultrasonic Flexural Vibration. At thesame time, material removal mechanism has been analyzed. The deep research foundationof ultra-precise manufacturing technology of hard and brittle materials is established.