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Within the expanding domain of electrical power demand, the future of power module packaging is entwined with the progress of (ultra) wide bandgap (UWBG) materials. These materials, like silicon carbide (SiC), aluminum nitride (AlN), and diamond, offer advantages with higher power density, decreased weight, and expanded operational abilities regarding temperature, voltage, and frequency. However, the pursuit of pushing these limits confronts challenges within insulation systems, which may struggle to endure the demands of these parameters, potentially resulting in unfavorable conditions like high electric field, space charge accumulation, electrical treeing, and partial discharge (PD), leading to insulation failure. The emphasis of this paper is to review the insulation challenges within (U)WBG power modules and recent research in mitigating the electric field stress at triple points (TPs) and resolving the PD issues. The manuscript first discusses the high electric field stress issue at triple points. Then, ceramic substrate materials, encapsulation materials, and the influence of harsh weather conditions on them are reviewed. The space charge, electrical treeing, and PD issues within encapsulation materials are analyzed under practical operation conditions of (U)WBG power modules like high frequency, temperature, and square wave pulses. Finally, the various strategies to alleviate the associated insulation challenges are meticulously discussed. While the identified mitigation strategies are able to strengthen insulation systems for packaging, their validation under actual operational conditions of (U)WBG power modules remains relatively unexplored, representing a potential avenue for further investigation. This review offers a valuable framework by providing the constraints of the current studies and recommendations for the future that can be utilized as a reference point for future research endeavors.
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This content will become publicly available on March 1, 2026
Navigating Strategies to Mitigate Insulation Issues Within High Power Density (U)WBG Power Module Packages: A Comprehensive Review Emphasizing Alternative Encapsulation Materials
The future of packaging for power modules hinges on the advancement of (U)WBG) materials like SiC, AlN, and diamond. However, pushing these boundaries faces significant challenges in insulation systems, which must withstand the demanding parameters involved. The repercussions include high electric fields, space charge accumulation, electrical treeing, and partial discharge (PD), all of which can lead to power module failure. This paper delves into reviewing these challenges within insulation materials of (U)WBG power modules and recent research aimed at mitigating electric field stress at triple points (TPs) and addressing PD issues. Beginning with the issue of high electric fields at TPs, the paper explores space charge, electrical treeing, and PD problems within encapsulation materials under practical operating conditions, such as high frequency, and high temperatures. Various strategies to tackle these insulation challenges are thoroughly discussed. While three prevalent mitigation strategies can address electric field issues at TPs, their validation under high-temperature conditions of (U)WBG power modules remains relatively unexplored, suggesting a potential shift towards alternative encapsulation materials. It is observed that the high-temperature dielectric liquids emerge as a promising solution to address thermal stresses for temperatures up to 350 °C with their stable dielectric properties and breakdown strength under repeated tests. Overall, this review provides a valuable framework by outlining the limitations of current mitigation strategies and offering recommendations for future research endeavors, with a particular emphasis on alternative encapsulants.
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- Award ID(s):
- 2306093
- PAR ID:
- 10652860
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Industry Applications
- Volume:
- 61
- Issue:
- 2
- ISSN:
- 0093-9994
- Page Range / eLocation ID:
- 3337 to 3358
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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