A High-Efficiency Searching Time Reduction Method for VCM Soft-Landing Operation During Chip Bonding

The chip precision bonding operation is a large-stroke high-speed and high-acceleration operation, which is usually realized by a voice-coil-motor (VCM). During the decelerating positioning to contact the chip, such high-dynamic movement could often be accompanied by inertial vibration which may impact the chip. To achieve a gentle contacting, the VCM soft-landing method is widely used in the bonding process, which designs a micro-searching-area to accommodate the inertial vibration, and starts up a low-speed uniform motion once the bonding system stabilizes. To minimize the time consumed in the searching area, this work proposed a high-efficiency searching time reduction (HSTR) method. Specifically, during the entire inertial vibration, a dynamic uniform motion actuation, which is conditionally planned for the VCM, starts the uniform motion as early as possible, and arrives at the target position precisely when the vibration attenuation is completed. The start-up moment planning is determined by the inertial vibration cycle, while the actuation velocity planning is dynamically decided by the real-time inertial vibration energy. The HSTR method can perform a proper actuation to speed up the VCM soft-landing without affecting the gentle contacting. Together with theoretical verification of its implementation and effectiveness simulation, the HSTR method is validated experimentally with different displacements, velocities, and accelerations.

Automated summary

The chip precision bonding operation is usually achieved by a voice-coil-motor (VCM) which provides large-stroke high-speed and high-acceleration movement. However, the inertial vibration during decelerating positioning may impact the chip. To achieve gentle contacting, the VCM soft-landing method is commonly used, which starts a low-speed uniform motion after the bonding system stabilizes. In this study, a high-efficiency searching time reduction (HSTR) method is proposed to minimize the time consumed in the searching area and speed up the VCM soft-landing without affecting the gentle contacting.