Numerical Investigation on the Effect of Squeegee Angle during Stencil Printing Process

The high requirement of smaller size, lighter weight, and high performance Printed Circuit Board (PCB) in electronic packaging has contributed to the wide application of stencil printing for soldering process. However, during stencil printing stage contributes major concern compared to other stages in Surface Mount Technology (SMT). Unsuitable process parameters can cause the soldering defects that can lead to product failure in further processes in the production line. An investigation has been conducted to predict the real-time observation of solder paste Sn96.5Ag3.0Cu0.5 (SAC305) filling process into stencil apertures as well as print quality in stencil printing by using Computational Fluid Dynamics (CFD) approach. A 3-Dimensional stencil printing model was developed and simulated in ANSYS Fluent 17 of different angles. It is found that squeegee angle 60° to 80° has potential to obtain the good print quality of solder paste.