|
|
|
|
|
|
|
|
Collaborative Cleaning Innovations
Production Floor |
|
Authored By:Mike Bixenman, DBA, Dirk Ellis Kyzen Corporation, Nashville, TN John Neiderman Speedline Technologies, Camdenton, MO TranscriptMoore's Law infers that the number of transistors on a chip doubles approximately every two years. Consistent with Moore's Law, high reliability electronic devices build faster processing speed and memory capacity using increasing smaller platforms. The trend toward highly dense assemblies reduces the spacing between conductors while yielding a larger electronic field. As the industry moves to higher functionality, miniaturization, and lead-free soldering, studies show that cleanliness of the assembly becomes more important. Residues under low standoff components, with gaps less than 2 mils, represent an increasingly difficult cleaning challenge. Collaboration from cleaning equipment and cleaning material companies has led to innovations for improving throughput and complete residue removal under low standoff components. The purpose of this paper is to report both mechanical and chemical innovations that open the process window. SummaryMoore's Law infers that the number of transistors on a chip doubles approximately every two years. Consistent with Moore's Law, high reliability electronic devices build faster processing speed and memory capacity using increasing smaller platforms. The trend toward highly dense assemblies reduces the spacing between conductors while yielding a larger electronic field. As the industry moves to higher functionality, miniaturization, and lead-free soldering, studies show that cleanliness of the assembly becomes more important. Residues under low standoff components, with gaps less than 2 mils, represent an increasingly difficult cleaning challenge. Collaboration from cleaning equipment and cleaning material companies has led to innovations for improving throughput and complete residue removal under low standoff components. The purpose of this paper is to report both mechanical and chemical innovations that open the process window. ConclusionsThe pace of technology development and innovation has changed the way customers and suppliers communicate and interact on a global scale. To understand the jobs that customers need done, suppliers identify customer needs that cannot be done satisfactorily with current solutions. Working from the outside-in, companies who supply pieces of the process collaborate by looking at the world from the customer's perspective to understand what the customer is trying to do and identify product or process characteristics for solving the customer's job. Star ting with a deep insight into the job the customer is trying to accomplish shifts the focus from solutions that customers use to the fundamental issues the customer is trying to solve. Cleaning process optimization requires a balance of chemical and mechanical effects. The job of the cleaning material is to remove flux residue and ionic contaminants. Aqueous cleaning material designs contain reactive materials at various concentration levels. Aqueous Low Reactivity cleaning material designs provide improved cleaning under low standoff components. The driving forces that improve performance come from the mixture of solvating materials that rapidly dissolve resin and rosin structures; low reactivity improves the cleaning rate but does not cause compatibility concerns; wetting lowers surface tension effects; and minor ingredients control foaming and protect solder joint finishes. Innovative designs run at lower wash bath concentrations ranging from 10-13%. The cleaning machine design is equally important. Fluid management is critical to containing and keeping the wash chemistry within the wash section. Fluid delivery is critical for penetrating and rapidly breaking the flux dam under low standoff components. To improve cleaning under low standoff components, research data indicates that fluid flow, pressure at the board surface, directional forces, and time in the wash improve the process cleaning rate. The wash section of the cleaning machine is highly important. Research data findings indicate that flux not adequately removed in the wash will not be removed in the rinse sections. The pace of innovation in the electronics field is staggering. This research paper highlights collaborative innovation in action. In today's rapidly growing global economy, customers kaisen (continuously improve) their processes. Listening and working closely with customer and supply partners who make up the ecosystem is how innovations that meet customer needs take place. Over the past several years, cleaning chemistries and cleaning machines have continuously improved to meet the challenges of cleaning highly dense and miniaturized circuit assemblies. Initially Published in the IPC Proceedings |
|
Comments
|
|
|
|
|
|
|
|
|