Contents lists available at ScienceDirect Applied Thermal Engineering journal homepage: www.elsevier.com/locate/apthermeng Liquid cooling module incorporating a metal foam and fin hybrid structure for high power insulated gate bipolar transistors (IGBTs) Jooyoung Lee a , Seokkan Ki a , Donghyun Seo a , Jaechoon Kim b, ⁎ , Youngsuk Nam a, ⁎ a Kyung Hee University, Department of Mechanical Engineering, Yongin, South Korea b Samsung Electronics CO., LTD., Semiconductor R&D Center, Hwasung, South Korea HIGHLIGHTS • The IGBT liquid cooling system incorporating a porous medium was investigated. • The optimal porosity exists due to the conflict between the convective and conductive flux. • The porous medium incorporating a metal foam and pin-fin array was investigated. • The pin-fin/metal foam hybrid porous medium provided a high cooling performance. ARTICLE INFO Keywords: IGBT Metal foam Pin-fin structure Liquid cooling Thermal management Electric vehicle ABSTRACT We propose a liquid cooling system incorporating a porous medium combined to the multiscale flow manifold. Specifically, this work compares two types of porous media by varying the porosity: the first type only includes a metal foam layer, and the second incorporates an additional circular pin-fin array within the metal foam. The thermohydraulic performances of each type such as the average junction temperature, temperature deviation, flow were investigated using both numerical and experimental approaches. Due to the influence of the additional thermal conductivity matrix by fin structure integration, the second configuration (metal-foam and pin-fin hy- brid type) provides a higher thermal performance compared to the first one. The suggested cooling solution with the second configuration could provide a very low thermal resistance (~0.185 K/W) with the pressure drop range between 5 and 15 kPa, which surpasses the performances of the previous-reported direct liquid cooling solutions such as the jet impingement, turbulator, and microchannel. This work will help develop high per- formance and compact cooling solutions for high power semiconductor applications such as an insulated gate bipolar transistor (IGBT) or a microprocessor. 1. Introduction The insulated gate bipolar transistor (IGBT) has been used in a broad range of applications, including renewable energy, Uninterruptable Power Supply (UPS) system, motor drive, rain traction, Electric Vehicle (EV)/Hybrid Electric Vehicle (HEV), consumer elec- tronics, and others [1,2]. Recently, the demand for miniaturization and high power density of IGBTs is increasing, which raises the possibility of thermal failures of IGBTs, such as heel cracks [3], solder joint cracks [4], delamination of bonded surfaces [5], and lift-off of wire bonds [6]. Since these types of thermal problems can lead to the total failure of the system by overheating, the development of the advanced cooling technologies for IGBTs is urgent. Direct liquid cooling technologies [7–25], including jet impinge- ment [24,25], turbulator [7,8], and microchannel [14–22], are one of the most available solutions for high power multiple IGBT modules due to their high heat transfer coefficients and low thermal resistances. Compared to the thermal resistance R th (> 0.8 K/W) of the conven- tional cold plates based on the indirect liquid cooling system, jet im- pingement, turbulator, and microchannel lowered R th up to 0.44–0.48, 0.2–0.55, and 0.13–0.24 K/W, respectively. Such improvement in the heat transfer can reduce the maximum temperature of IGBT-diode pairs and provide uniform temperature distribution, which can prevent a local failure within IGBT modules. However, these promising methods typically require a high pressure drop for such low thermal resistance. The small diameter of jet nozzles [24], the complex flow path for the https://doi.org/10.1016/j.applthermaleng.2020.115230 Received 24 October 2019; Received in revised form 17 March 2020; Accepted 20 March 2020 ⁎ Corresponding authors at: Package Development Team, Semiconductor R&D Center, Samsung Electronics CO., LTD, South Korea. (Jaechoon Kim). Department of Mechanical Engineering, Kyung Hee University, 1732 Deokyoungdaero, Giheung, Yongin 446-701, South Korea, (Youngsuk Nam). E-mail addresses: jaechoon.kim@samsung.com (J. Kim), ysnam1@khu.ac.kr (Y. Nam). Applied Thermal Engineering 173 (2020) 115230 Available online 21 March 2020 1359-4311/ © 2020 Elsevier Ltd. All rights reserved. T