Ball Misplace Mitigation through Process Optimization of Advanced Leadframe Package
Bryan Christian S. Bacquian *
New Product Development and Introduction, STMicroelectronics, Inc., Calamba City, Laguna, 4027, Philippines.
Frederick Ray I. Gomez
New Product Development and Introduction, STMicroelectronics, Inc., Calamba City, Laguna, 4027, Philippines.
Edwin M. Graycochea Jr.
New Product Development and Introduction, STMicroelectronics, Inc., Calamba City, Laguna, 4027, Philippines.
*Author to whom correspondence should be addressed.
Abstract
One of the challenging assembly processes in semiconductor manufacturing industry is stencil printing using solder paste as direct material. With this technology, some issues were encountered during the development phase of an advanced leadframe device and one of which is the solder ball misplace or off-centered ball. This paper, hence, focused on addressing the ball misplace issue at stencil printing process. Comprehensive parameter optimization particularly on the print speed and print force was employed to eliminate or significantly reduce the ball misplace defect at stencil printing process. With this process optimization and improvement, a reduction of around 96 percent ball misplace occurrence was achieved.
Keywords: Solder bumping, stencil printing process, off-centered ball, leadframe, assembly.