Excerpt Chapter 5: 'The Printed Circuit Designer’s Guide to... Thermal Management with Insulated Metal Substrates, Vol. 2'
August 9, 2022 | Didier Mauve and Robert Art, VentecEstimated reading time: 2 minutes

Chapter 5: Boosting Thermal Performance with Multilayer IMS
In The Printed Circuit Designer’s Guide to... Thermal Management with Insulated Metal Substrates (Vol. 1), the authors briefly discussed the issues around combining multiple layers of copper foil, dielectric, and substrate materials and the design opportunities given by the latest generation of thermally conductive thin cores and prepregs.
The latest thermally conductive materials, prepregs, and cores allow designers to reconsider the thermal management approach. They can offer a simple and ready-to-use solution to address thermal issues on existing multilayer boards.
Through necessity, the industry has already come up with many solutions over the years, such as thermal vias, thermal coins, and inserts. All these existing solutions require either the use of thick copper foil and/or the use of heavy copper coins, thus leading to an inevitable inflation in cost and weight. We can now analyze alternative designs made possible by the arrival of multilayered IMS. The following application examples illustrate the concept and the main benefits of multilayered IMS.
Figure 5.1: Single-sided single layer.
The PCB design with insulated metal substrates is by no means limited to single-sided and single-layered circuits (Figure 5.1), although these are predominantly the types of circuits used in LED-lighting and power electronics applications.
There are several versatile ways to take advantage of IMS’s enhanced thermal properties in situations that demand various other attributes such as physical formability or compliance, an intricate shape or small dimensions, or a complex circuit layout that would be fulfilled with a multilayered PCB if it weren’t for the thermal issues.
If a formable grade of laminate (such as, for example, aluminum 5052 with a thin, non-reinforced dielectric) is specified, a single-sided circuit can be post-formed into three-dimensional shapes. This may help to design a circuit board that must fit inside a small or unusually shaped enclosure, or to cram more electronic circuitry within a limited space, or maybe ease assembly of a product if there is only minimal access to install electronic circuit boards. The aluminum layer is machined to reduce its thickness in the bend area.
Figure 5.2: Single-sided double layer.
Also, it is possible to build insulated metal substrates into multilayered IMS structures (Figure 5.2) with thermally conductive laminates and prepregs using plated-through holes for Z-axis interconnection.
In situations where the metal base is not an option, but the component temperature needs to be reduced, an alternative construction may be necessary; the thermal conductive cores and prepreg may be combined to create the entire board or may be used in a hybrid construction combining conventional FR-4 and thermal conductive cores or prepreg.
To continue reading this chapter, download your copy of this book from the I-007eBooks library today!
Testimonial
"Advertising in PCB007 Magazine has been a great way to showcase our bare board testers to the right audience. The I-Connect007 team makes the process smooth and professional. We’re proud to be featured in such a trusted publication."
Klaus Koziol - atgSuggested Items
Trouble in Your Tank: Minimizing Small-via Defects for High-reliability PCBs
08/27/2025 | Michael Carano -- Column: Trouble in Your TankTo quote the comedian Stephen Wright, “If at first you don’t succeed, then skydiving is not for you.” That can be the battle cry when you find that only small-diameter vias are exhibiting voids. Why are small holes more prone to voids than larger vias when processed through electroless copper? There are several reasons.
The Government Circuit: Navigating New Trade Headwinds and New Partnerships
08/25/2025 | Chris Mitchell -- Column: The Government CircuitAs global trade winds continue to howl, the electronics manufacturing industry finds itself at a critical juncture. After months of warnings, the U.S. Government has implemented a broad array of tariff increases, with fresh duties hitting copper-based products, semiconductors, and imports from many nations. On the positive side, tentative trade agreements with Europe, China, Japan, and other nations are providing at least some clarity and counterbalance.
How Good Design Enables Sustainable PCBs
08/21/2025 | Gerry Partida, Summit InterconnectSustainability has become a key focus for PCB companies seeking to reduce waste, conserve energy, and optimize resources. While many discussions on sustainability center around materials or energy-efficient processes, PCB design is an often overlooked factor that lies at the heart of manufacturing. Good design practices, especially those based on established IPC standards, play a central role in enabling sustainable PCB production. By ensuring designs are manufacturable and reliable, engineers can significantly reduce the environmental impact of their products.
50% Copper Tariffs, 100% Chip Uncertainty, and a Truce
08/19/2025 | Andy Shaughnessy, I-Connect007If you’re like me, tariffs were not on your radar screen until a few months ago, but now political rhetoric has turned to presidential action. Tariffs are front-page news with major developments coming directly from the Oval Office. These are not typical times. President Donald Trump campaigned on tariff reform, and he’s now busy revamping America’s tariff policy.
Global PCB Connections: Understanding the General Fabrication Process—A Designer’s Hidden Advantage
08/14/2025 | Markus Voeltz -- Column: Global PCB ConnectionsDesigners don’t need to become fabricators, but understanding the basics of PCB fabrication can save you time, money, and frustration. The more you understand what’s happening on the shop floor, the better you’ll be able to prevent downstream issues. As you move into more advanced designs like HDI, flex circuits, stacked vias, and embedded components, this foundational knowledge becomes even more critical. Remember: the fabricator is your partner.