iNEMI SOLDER PASTE DEPOSITION PROJECT – FIRST STAGE REVIEW OPTIMIZING SOLDER PASTE PRINTING FOR LARGE AND SMALL COMPONENTS

摘要

The widely recognized industry standard IPC-7525 hasrnbeen used as the starting point for an experimentalrnprogram that explores the effect of varying the keep outrndistance for 0201 and 0402 chip components, CSP andrnSOP with pitches down to 0.4mm, and larger componentsrnrepresented by CCGA. Other variables that werernincluded in the experimental program to determine ifrnthey had an effect on the sensitivity of paste transfer tornkeep-out distance included stencil type, step height andrnsolder type.rnIn the first stage of the project the printing to each padrnwas measured with automated 3D SPI systems andrnoptimum combinations of parameters identified byrnstatistical analysis. In this paper the authors willrnexplain the methodology chosen to achieve the projectrnobjectives and indicate the direction of likely future work.rnEarly results indicate that a key objective of the project,rnto provide evidence to support the case for a reduction inrnthe keep out distances below the current industryrnstandard, might be achievable.