Key processes of silicon microball bearing

The key processes of silicon microball bearing were investigated. First, the structure of raceway, the number of rolling elements and the nozzle of the bearing chamber of the microball bearing were designed. Then, the Halo Etch technology was employed to fabricate the blade with various characteristic dimensions and to improve the uniformity of etch rate and the pattern precision, thus, reducing the imbalance of rotor and increasing the stability of the microball bearing at high speed. Moreover, the intermediate-layer bonds and shadow mask technologies were used to encapsulate the bearing chamber and reduce the thermal deformation caused by the extremely high temperature and to avoid the clogging of the bearing chamber and the ball raceway adhesion caused by the deposited intermediate materials. A strategy for the design and fabrication of microball bearings in Micro-electromechanical System (MEMS) is provided.