Research on Dynamic Characteristics of Air Static Pressure Spindle for Silicon Wafer Grinding Machine

doi:10.3901/JME.2025.05.108

Abstract

Abstract: The air-bearing spindle is a critical component of the ultra-precision grinding machine for silicon wafers, and its stiffness significantly influences the formation of surface grinding marks on the wafer. First, based on the power spectral density analysis method, the frequency composition of the grinding marks on silicon wafers after grinding is analyzed. Subsequently, a rotor dynamics model of the spindle considering the stiffness of the contact surfaces and grinding forces is established to analyze the impact of axial and radial stiffness on the rotor frequencies. The relationship equation between the rotor frequency and the axial and radial stiffness is derived. Simulation results indicate that compared to axial stiffness, radial stiffness has a more sensitive effect on the grinding marks. Finally, to reduce the amplitude of the silicon wafer grinding marks, the optimal design criteria for the stiffness of the air-bearing spindle used in silicon wafer grinders are determined: an axial stiffness of 800 to 1 000 N/μm and a radial stiffness of 90 to 110 N/μm, resulting in rotor frequencies between 300 and 410 Hz. An improved spindle rotor structure is designed under which the amplitude of the grinding marks can be reduced by 20 nm. It provides a reference for the design of air-bearing spindles for silicon wafer grinders.

Key words: silicon wafer grinding machine, air static pressure spindle, axial stiffness, radial stiffness

CLC Number:

TH113

XU Jiahui, KANG Renke, ZHU Xianglong, DONG Zhigang, LI Meng. Research on Dynamic Characteristics of Air Static Pressure Spindle for Silicon Wafer Grinding Machine[J]. Journal of Mechanical Engineering, 2025, 61(5): 108-116.

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