Influence of Temperature on Flexible Printed Circuit Board During Reflow Soldering

The increasing demand for flexible, lightweight, compact, and cost-effective electronic products has led to a growing preference for Flexible Printed Circuit Boards over Rigid Printed Circuit Boards. However, thermal challenges during the reflow soldering process can significantly impact FPCBs. When exposed to elevated temperatures, Flexible Printed Circuit Boards are highly susceptible to deflection and thermal stress. This study examines the impact of temperature profile on FPCBs during the reflow soldering. Deformation measurements for both FPCBs and Rigid Printed Circuit Boards were obtained using a KEYENCE ­LK-G152 laser sensor installed at a reflow oven’s entry and exit points. The experiment evaluated two temperature profiles, soaking and ramp profile, as variables. Findings revealed that FPCBs experienced greater deformation under the ramp profile, whereas RPCBs exhibited more deformation under the soaking profile. This research provides valuable insights for engineers and Printed Circuit Board designers, offering practical guidelines for optimizing mass production in the microelectronics industry.