Speedline Technologies completes study on lead-free process optimization
Aug 30, 2005
The Advanced Development Group of Speedline Technologies, Inc., in cooperation with Agilent Technologies, has concluded a three month Design of Experiment (DOE) to understand and quantify variables in a lead-free manufacturing process.
A report of findings will be presented at the SMTA International Conference in Chicago in September 2005.
Fundamental conclusions highlight that the positional accuracy of the paste deposit relative to the pad is the critical element in ensuring good fine pitch lead free assemblies, and is even more critical for some formulations than others. Solder volume can be readily managed across the supplier base with printer variables and stencil design. As with any solder pastes (lead-free and lead-bearing), the use of enclosed print heads such as the Rheometric pump will present advantages such as better aperture fill, however it is not the determining factor for a high quality process. The atmosphere and profile of the reflow oven contribute substantially to the overall quality of the Lead-free assembly.
The goal of this first DOE was to understand the impact of the positional accuracy of the printed solder paste to the component pad, the positional accuracy of the placed component to the component pad, and atmosphere and profile of the reflow process.
The experiment was enabled by the accuracy and flexibility of Agilent's Medalist SJ50 Series II Automated Optical Inspection (AOI) systems.
Dr. Gerald Pham-van-Diep, Director of Advanced Development for Speedline Technologies stated, "This study was undertaken to review the full potential for process needs as customers convert to lead free process technologies. It demonstrates that the process changes required in most situations to convert to lead free are not as daunting as some suppliers would have the industry believe. In essence, with appropriate process review, process development work and management of the variables available to the manufacturer, the switch to producing high-quality lead-free assemblies is achievable."