A Theoretical Flow Model of Thrust bearing in Gas spindle for wafer grinder

摘要

The gas spindle is a key component in wafer thinning equipment. The performance of the gas spindle directly affects the wafer processing quality. By establishing the mathematical model of the gas spindle thrust bearing flow field, the gas flow process in the orifice and gas film is studied, and the bearing capacity distribution of the thrust bearing is obtained. The variation of the bearing characteristics of the thrust bearing with the thickness of the gas film is analyzed in detail. Between 1μm ~ 11μm, the bearing capacity declines gently, and the capacity changes by only 2%. Between 12μm and 30μm, the bearing capacity has a significant downward trend, from 6800N to 1800N, a decrease of 73%. After 31μm, the change in bearing capacity is attributed to a gradual change. Before 18μm, the stiffness value increases with the increase of the thickness of the gas film, and increases rapidly. The maximum stiffness value appears at 18μm, which is 376N/μm. In addition, compared with the increasing trend of stiffness value, the downward trend is relatively gentle. Through the above research, it provides a theoretical reference for the development of thinning equipment.