Robust Design of PCB Asembly Process for XSON Package
Authors: ChinFei Ng, Shirley Ng and Patrick Aun Company: Sanmina (M) Sdn Bhd Date Published: 4/12/2016
Abstract: The miniaturization trend has driven to the introduction of extremely miniaturized components such as extra small outline no lead (XSON) package. When developing a miniaturized component, it is critical that the new developed component must be as compared to or perform better than standard component in the open market. In an attempt to implement an XSON package, unfortunately, this miniaturized part has created soldering issue in during the Printed Circuit Board (PCB) assembly process that has resulted in electrical failure. The present paper provides a real business case of yield drop due to soldering issue of XSON package attributing to camera failure on both front and rear cameras. Systematic DMAIC approach is being utilized efficiently to find out the root cause of the soldering issues. It was found out that the termination of the component is very tiny (0.1mm only) and having no heel extension to allow for any process or component tolerances. Test board design has been developed by using different padstack designs evolving from adding the heel extension with different pad shapes targeting to minimize the possibility of solder short potentials while keeping the heel extension to allow for any process or component tolerance. A robust assembly process recipe is being established to ensure the soldering process is insensitive to the noise of different production environment. No soldering issues were observed on the optimized padstack design for XSON package throughout the experiment.