RSOB Shorting Defect Resolution through Looping Optimization and Ball Placement at Wirebond Process
Norman S. Calma
Back-End Manufacturing & Technology, STMicroelectronics, Inc., Calamba City, Laguna, 4027, Philippines.
Jonathan C. Pulido *
Back-End Manufacturing & Technology, STMicroelectronics, Inc., Calamba City, Laguna, 4027, Philippines.
Frederick Ray I. Gomez
Back-End Manufacturing & Technology, STMicroelectronics, Inc., Calamba City, Laguna, 4027, Philippines.
*Author to whom correspondence should be addressed.
Abstract
Wirebonding process is one of the most challenging assembly manufacturing process in semiconductor packaging industry. This paper discussed the wirebonding challenge and the solution to resolve the wire to die shorting on reverse stitch on ball (RSOB) and prevent irregular looping height for the substrate land grid array (LGA) device. Comprehensive parameter optimization was done particularly on the wirebond looping to ensure that no wire depression and no capillary hitting would occur wirebonding setup. Ultimately, the optimized wirebonding parameter prevented the occurrence of looping issues during the lot process. For future works, the configuration and technique could be applied on packages with similar situation.
Keywords: Die reference, looping profile, pattern recognition, wirebonding process