PROCESS PLANNING FOR AREA ARRAY COMPONENT ASSEMBLY

Surface mount technology is continually evolving to meet the technical challenges posed by market driven needs. This has resulted in an increase in the circuit density and functionality per unit area of the board. At the same time, the complexity of the component has also increased. Packages that provide a higher density of inputs/outputs are replacing less efficient components. This trend has resulted in the increased use of area array devices, especially ball grid arrays, in the surface mount assembly of printed circuit boards. Area array devices also present many processing advantages over the fragile perimeter leaded devices.
Through this research, a DSS has been developed to assist a process engineer in planning for the assembly of area array (ball grid array) devices on printed circuit boards. The factors that affect the yields are addressed. These include materials, equipment, environment, and the process steps themselves. Materials related considerations include the board, solder paste, components, and tooling. Process recommendations are provided for solder paste deposition through stencil printing, component placement, solder reflow, and inspection. Information on how these factors affect the assembly process has been determined (through related research) and is contained within the knowledge base used by this DSS. The system is user friendly, menu driven and is interactive in nature.