Printed circuit board process based thermopile-type heat flux sensor used for monitoring chips

Abstract

• Proposed PCB process based thermopile-type HFS can sense heat flux accurately. • Established sensing equation of HFS can accurately predict the performance. • Manufacturing process was proposed and used to manufacture HFS. • Manufactured HFSs were applied to monitoring heat flux of chip successfully. • Developed HFS can be embedded in system without affecting temperature field . At present, most of existing heat flux sensors (HFSs) have the disadvantages of large volume, complex manufacturing process, poor embedding property and affecting existing thermal field distribution, which seriously hinders the development and practicality of chip thermal management technology. To address the above issues, this paper presents a principle and structure of a novel thermopile-type HFS based on printed circuit board process (PCB) for monitoring heat flux of chips. According to the proposed principle, PCB process based thermopile-type HFS was designed and manufactured and its corresponding sensor equation was established. Experimental setups were built and manufactured HFSs were experimentally tested and also applied to monitoring the heat flux of chip on PCB, which is mimicked by a small electronic heating system. Theoretical and experimental results show that HFS designed and manufactured according to the proposed principle can sense heat flux accurately with the sensitivity, nonlinear error, repeatability error, time response and measurement range of 0.2670 μV/(W/m 2 ), 1.59%, 1.30%, 5 s and 0–20 kW/m 2 , respectively, and has the potential to be conveniently and flexibly embedded in electronic system to measure heat flux of chips with affecting existing temperature field as little as possible.