RF components are an integral part of the 5G revolution. The amount of RF front end components required has doubled during the transition from 4G to 5G. This, obviously, goes in the opposite direction of the industry’s miniaturisation trend where everything needs to be smaller and denser.
That’s why RF antennae trends require thinner and more efficient packages. Integrated Antenna in Package 5G components are rapidly moving from asymmetric and stacked antennae to ultra thin hybrid and fan out with multi band and higher frequencies. This allows, at least, keeping devices on a similar size as with previous generations.
But higher frequency signal transmission, increasing component count and adding more processing and functionality in the same space come at a cost and with elevated design and reliability requirements.
That’s where Package level EMI shielding comes in.
What is EMI Shielding?
ElectroMagnetic Interference Shielding is the reflection or absorption of Electromagnetic radiation through the use of a shielding material. It protects signals from being externally disrupted while also preventing them from interfering with surrounding components.
In the electronics industry and in simple terms it is the practice of isolating the signal of components so that they don’t interfere with each other.
Board level shielding
Traditionally this separation is being done on a Board level. You would solder a lid or conductive enclosure on the board, covering the component and separating it from whatever you wanted to be separated. As you can imagine enclosures are heavy and require a lot of board space, limiting the design flexibility.
Remember when we said RF components doubled in 5G applications? Well, with traditional board level shielding you would have to double enclosures, weight and space. If this doesn’t sound great it’s because it isn’t.
Package level EMI Shielding
Enter Package level EMI shielding. In a stroke of genius engineers decided that we don’t need enclosures anymore. We can fend those signals within the package itself.
How? We dig walls in the molded package, we fill them with EMI shielding pastes and then we finally cover them with a conformal coating. This way we can have multiple conductive partitions within the package and isolate multiple components within the same package, leading to high density designs and miniaturisation.
Package level EMI shielding enables Faraday cages directly applied at the package level. This reduces the dimensions and weight of the overall design and provides a compact and effective shielding method.
We, as Caplinq, can aid you with most of these steps. From Die attach materials to Encapsulants and Molding compounds, we have solutions for every step of the semiconductor packaging process. Now we are happy to announce that we also provide Henkel’s newest and greatest EMI shielding materials.
After cutting the wall and in order to jet dispense EMI shielding there are electrically conductive, void free pastes such as EMI 3620FA that can be used to fill trenches and gaps and exhibit no cracks or delamination after reliability testing.
The next step is to coat and cure the package. The conformal shielding needs to have a uniform coating thickness within 3–10um, be applied by atomizing spray and shield in a range between 10MHz and 10GHz. These are all properties of EMI 8880S, a sprayable, effective material with extremely low resistivity and good laser marking visibility. All in all, if you are interested in transitioning to package level shielding, we got you covered.
Printed Silver interconnects
EMI shielding is not the only solution for the miniaturisation of packages. Printed silver interconnects with SinterINKS (Sintering Inks) are also a great solution to replace wire bond interconnects, print highly conductive circuits and at the same time have improved RF performance at frequencies up to 110GHz.
These materials can help drastically reduce the package footprint in height and width and and also operate in higher frequencies. But we are slowly starting to drift away from the scope of this blog.
EMI Shielding and Sinterinks will be thoroughly discussed and presented by Henkel’s Business Developer, Ruud de Wit during the upcoming Microtech 2021.
Smart Electronics’ market trends like 5G are driving advanced semiconductor packaging innovations towards higher functionality, enhanced connectivity at higher frequencies, smaller form factors (miniaturisation) and reduced power consumption. Especially for next generation RF devices including antennas, package level EMI shielding, and shorter interconnects are key to enable next generation mmWave developments running at increasing frequencies above 100 GHz.Ruud De Wit, Henkel Electronic Materials
This is part of Ruud’s abstract for the upcoming MicroTech 2021 Online Conference on Heterogeneous Integration. This online event takes place on the 25th of March and is organised by iMAPS UK. MicroTech 2021 is the Annual IMAPS-UK Conference which focuses on key emerging markets and their associated technological challenges.
Even though we are not IMAPS members yet, we can confidently suggest attending. We joined multiple online webinars and workshops over the last year and have thoroughly enjoyed them. They have successfully adapted to the current remote circumstances and there’s always something new and exciting to learn. That’s why we are happy to support and promote them for their great work on sharing and supporting industry knowledge and developments.
Want to learn (even) more about EMI shielding and all things semiconductor? Follow our blog or contact us for additional information.