A VCM Active Actuation Method for Bonding Time Reduction in Chip Packaging Process

Abstract

The voice coil motor (VCM) is widely adopted in chip packaging to achieve high-speed, large-stroke, and high-precision bonding operations. However, the inertial vibration, induced by high-speed high-acceleration motions, may cause significant impact on the chip pad, and affect the packaging efficiency and quality. To achieve a soft-landing chip contacting, the current method usually adopts a microgap searching area to tolerate the inertial vibration, and a low-speed uniform motion is applied after the bonding head is settled down. In order to improve the operation efficiency and reduce the time used in the searching area, this article presents a VCM active actuation (VAA) method to enable switching to the uniform motion in advance and interfering the inertial vibration through the defined actuation conditions. The actuation moment condition is determined by the direction and energy of the inertial vibration, and the actuation amount condition is determined by the effect of the uniform-motion speed on the soft-landing performance. The VCM can be actuated at the right moment with a proper amount in the inertial vibration process to reduce the vibration and searching time, without affecting the rest low-speed soft-landing operation. Based on the simulations, the VAA method is tested experimentally and validated at different velocities, accelerations, and displacements.