MODEL OF PROCESS CAPABILITY OF SOLDER PASTE PRINTING
Author: A. Paproth Company: Dresden U. of Technology Date Published: 9/12/1999
Abstract: The growing demand for product performance and the advances in semiconductor devices increase the complexity of the boards and packaging of electronic systems. This leads to faster, smaller and lighter electronic system. The key to miniaturisation of electronic products is the use of fine pitch surface mount packages. At the same time the need for control of manufacturing quality is becoming more evident. This is one of the reasons for intense study of quality of solder paste printing. Another reason is the high influence of quality of solder paste printing on the whole assembly quality. The knowledge of machine and process capability can be important tool for control of quality in manufacturing of electronic products. The capability of placement machines was investigated at the Dresden University of Technology in the last years and described 1,2. At this time the machine and process capability of solder paste printing are under investigation. The goal of this investigations is to create a mathematical model to describe the quality of solder paste printing using the machine and process capability. The paper will discuss the affect of stencil accuracy; alignment and printed circuit board layout on the placement of solder paste deposit. Further the paper will show the influence of printing parameters, stencil type and solder paste (type, viscosity, temperature) on the transferred volume of solder paste. The developed experimental and measurement methods will be presented and the process capability according to the named influences will be defined. In addition, the paper will discuss away of modelling the quality of solder paste printing.