Study on the Electromagnetic and Thermal Characteristics of Aerostatic Spindle for Wafer Grinding

With the development of advanced IC packaging technology, wafers are required to become thinner and thinner. The 12-inch memory wafer has reached within 25um, which requires a higher-performance aerostatic spindle of the wafer grinder. The spindle motor power of the wafer grinder is large, which generates a lot of heat. The heat causes the temperature rise of the aerostatic spindle, which adversely affects the wafer grinding accuracy and the reliability of the spindle motor operation. In this paper, the field-circuit coupling model of the spindle motor in the aerostatic spindle is established. The transient two-dimensional electromagnetic field is analyzed, and the no-load and load characteristics of the motor are obtained, which provides theoretical support for the design of the spindle motor. Using motor loss as the heat source, through the one-way coupling of electromagnetic field and temperature field, establish an aerostatic spindle thermal analysis model, and the steady-state temperature field of the aerostatic spindle and the rotating shaft is simulated and analyzed, and the temperature distribution of the aerostatic spindle and the rotating shaft is obtained, and the thermal deformation is analyzed. This paper has certain reference value for the optimization design of aerostatic spindle.