Recent advances in computer-aided tool design have reduced the cost of expensive prototype tooling. CAD-based software has 'been promoted for the design of plastic IC encapsulation tooling, but until recently, no real-time data from the encapsulation process had been collected to verify its effectiveness. A novel approach was used to capture the plastic IC encapsulation process. A 24x24mm PBGA mold was equipped with a window and video camera to capture the encapsulation process. Computer simulations of the cavity were also performed, using a new reactive 3-D flow simulation software suite. Computer predicted results showed only partial agreement with the observed molding results due to simplifications of the model required for timely simulation runs. More detailed models would provide better predictions at the cost of lengthy computer CPU time. IntroductionMost integrated circuits (IC) are packaged using transfer molding of epoxy compounds. Design of the molds used in these processes is a costly and lengthy process. The prototypes are expensive, because each piece of tooling must be designed, machined, and tested in a very short amount of time. Prototypes often require numerous modifications and rework. To minimize the impact of these changes, new designs are typically created on CAD (Computer-Aided Design) systems, which allow rapid modification of drawings at any point in the design process. Although these systems have simplified the drawing process, they have not affected the fabrication process. Each iteration in the design process still requires rework of the existing mold or the fabrication of a new mold, often at a cost of tens of thousands of dollars. Large amounts of time and money are also spent testing each revision. Mold design and flow simulation have been proposed as a more efficient methodology for tool manufacturing [l].