Basic Research On Hybrid Technology Of Ultrasonic Vibration Assisted Chemical-Mechanical Grinding Silicon Wafer

With the rapid development of microelectronics technology industry, as major semiconductor materials for the production of microelectronic chips, precision and ultra-precision processing technology of silicon wafer is also increasingly being taken seriously. On the basis of analyzing the present situation of chemical mechanical grinding and ultrasonic machining at home and aboard, according to technical status and existing problems of traditional grinding, especially for the diameter of silicon wafer increasing, constantly, surface roughness, material removal rate and efficiency of silicon wafer grinding are becoming an urgent problem to be solved and improved. So the research subject of ultrasonic vibration chemical-mechanical hybrid grinding new technique is proposed. The compound grinding technique is novel processing technique that ultrasonic processing and chemical mechanical grinding are integrated, promote the grinding tool grinding silicon with different forms of vibration, such as ultrasonic longitudinal vibration, ultrasonic shear vibration and ultrasonic elliptic vibration, to achieve the purpose of improving the quality of wafer processing.Firstly, the material removal mechanism of the composite abrasive silicon technology is described and analyzed. Then, the structural design of the grinding tool of a key part of the technology is analyzed in detail and designed, and made Simulation analysis on vibration mode by ANSYS and experimental verification. Finally, according to the grinding mechanism and the existing experimental conditions, to carry out experimental research of ultrasonic vibration assisted chemical-mechanical grinding silicon wafer. From the theoretical analysis and the experimental results obtained that there were significant improvements in silicon processing effects when joining the ultrasonic vibration. Among these circumstances, ultrasonic elliptical vibration mode of grinding tool is the best for the quality of wafer processing, followed by the bending vibration mode, the third is the longitudinal vibration mode.In short, hybrid technology of ultrasonic vibration assisted chemical-mechanical grinding have a larger improvement for surface roughness, material removal rate and processing efficiency of silicon, which will have an important theoretical significance for the precision and ultra-precision machining.