“ALSET” Heat-Reducing & Low Inductance Laminated Busbar for Power Modules

<Overview>

Mitsubishi Chemical Corporation (MCC) introduces a resin sheet that combines high thermal conductivity and high electrical insulation, making it suitable for heat dissipation in power modules used in applications such as inverters. By bonding this sheet to cooling plates for transfer molded power semiconductor devices, it enables efficient heat dissipation, reduction of total system cost, low-profile inverter design, and simplification of inverter structures. In addition to the existing 15 W/mK sheet, an 18 W/mK sheet (under development) has now been added to the lineup.

Furthermore, MCC not only develops and manufactures the sheets and fillers themselves, but also conducts performance evaluations in module-bonded configurations that reflect actual customer usage conditions. Based on customers’ evaluation results, we offer recommendations for optimal usage methods and optimize sheet formulations tailored to specific applications.

<Features>

In case of IMS (Insulated Metal Substrates), resin-based insulating thermal interface sheets are widely used. In addition to conventional IMS applications, MCC’s thermal conductive sheets are now compatible with bonding to cooling plates for transfer molded power semiconductor devices. Functions that previously required a combination of multiple materials - electrical insulation, heat dissipation, and adhesion - can now be achieved with a single resin sheet. This contributes to improved module reliability, reduced total cost, and low-profile inverter design, enabling simpler inverter designs. Since the sheet itself provides the insulation function, it is applicable to a wide range of bonded applications that require both insulation and heat dissipation, including discrete devices, non insulated 2 in 1 modules expected to emerge in the future, and other similar use cases.

In addition to the previously proposed 15 W/mK sheet, development of an 18 W/mK sheet is underway, and samples are now available. Both products exhibit a dielectric withstand voltage of AC 7 kV (typical value at a thickness of 150 μm).

Achieving high thermal conductivity in resin sheets generally requires increasing the content of inorganic fillers, which often results in reduced flexibility. To address this issue, our sheets utilize a proprietary boron nitride (BN) filler design, significantly improving handling characteristics. Because the BN filler itself contributes substantially to thermal performance, high thermal conductivity can be achieved even at relatively high resin content. As a result, excellent flexibility - which is critical for ease of handling - is maintained while still achieving high thermal conductivity.

When selecting heat dissipation materials for applications requiring superior thermal performance - such as traction inverters for xEV - we encourage you to consider this product as one of your options.

Contact information: MCJP-MBX-MCC_BNPROJECT@mchcgr.com

https://www.m-chemical.co.jp/en/products/departments/mcc/nes/product/1215372_9004.html