A novel rapid micromotion compensator for high-precision chip bonding manufacturing

Large-stroke high-speed positioning stages play a significant role in microelectronic packaging manufacturing. Considering the problem of Z-axis bonding position error caused by inaccurate positioning, diverse chip pad sizes, and other interfering factors, this study proposes a rapid high-precision compensating method with a micromotion compensator to reduce the positioning error in the Z-axis direction. In the study, the micromotion compensator with a unique piezoelectric-spring structure is designed and implemented on the stage working end. Based on the static force analysis and energy storage/dissipation analysis, the exact extension and retraction amount of the compensator is determined in relation to the spring preload force. From the frequency response analysis, the micromotion compensator can achieve a high-frequency performance with appropriate spring stiffness. Thus, the compensator can loyally react to the positioning error and rapidly output the exact compensating amount for the Z-axis operation. Based on the working principle and characteristics of the compensator, the compensating system is implemented. The experimental results show that the compensator can achieve nanometer precision positioning for the motion stage. The proposed Z-axis working-end compensator is particularly useful in the real-time chip bonding manufacturing process for rapid and accurate positioning.