Examination of Evaluation Method for In-Plane Effective Thermal Conductivity of Printed Circuit Board

In recent years, the heat generation density of electronics has increased due to the miniaturization of electronic devices. Therefore, heat dissipation through PCB (Printed Circuit Board) is becoming important. Accurate effective thermal conductivity value is important for the thermal design of PCB. Generally, the effective thermal conductivity of PCB differs in the thickness direction and the in-plane direction. However, the measurement of the effective thermal conductivity of PCB in the in-plane direction is difficult. Our previous study proposed the concept of the measurement method of the in-plane effective thermal conductivity of PCB. [1] However, in the previous study, we did not detect the value of the effective thermal conductivity. In this study, the evaluation method to detect the value of the in-plane effective thermal conductivity is discussed. The results show that the effective thermal conductivity can be accurately calculated using the amount of heat through the PCB in the in-plane direction calculated from the thermal conductivity ratio.