There are many EMI shielding materials to choose from when determining how to effectively control EMI within an electronic device. In this post, we focus on die-cut foil tapes for EMI shielding. Foil tapes with conductive adhesive provide effective shielding properties as the thin foil layer ensures good electrical contact with the component surface. Let's take a look deeper at EMI and why foil tapes may be the best-suited material for your application.
What is EMI and Why is it Important?
Electromagnetic interference is unwanted “noise” or interference in an electrical path or circuit caused by an outside source. EMI can be caused by natural or man-made sources and can cause electronics to malfunction or to completely stop working. Therefore, EMI shielding and grounding components are important pieces in the design of electronic devices.
EMI Shielding Foil Tape Construction
EMI foil tapes are constructed of metal foil backings coated with conductive adhesive. Foil tapes establish secure electrical contact with the application surface by means of a conductive acrylic adhesive. The broadly distributed conductive particles provide many low-resistance paths between the backing of the substrate.
As you can see in the diagram below from 3M’s Insulating and Conductive Tapes Brochure, total tape thicknesses range from 2.6 mil to 6.0 mil. Foils include aluminum foil, copper foil, embossed foil, and tin-plated copper foil.
Die-Cutting EMI Shielding Foil Tapes
EMI shielding foil tapes are supplied on a kraft paper liner. Marian can provide the foil tapes die-cut to exact sizes and shapes for efficient implementation into electronic devices by providing the part with extended pull tabs, split liners, kiss-cut on continuous rolls, crease lines for bending, or any number of other presentations. They can be combined and laminated with other materials to solve multiple issues – insulators, magnetic materials, thermal materials, etc. We work closely with our customer's manufacturing process team to design for manufacturing at every stage of the process.
Solution Case Study: EMI SHIELDING PART FOR LCD DISPLAY
In this solution case study, Marian provided die-cut copper foil tape (3M 1126) to meet the EMI requirements of an LCD display. The die-cut copper foil tape was designed to cover the complete backing of the display to prevent electromagnetic emissions or interference. The final die-cut part has a complex geometry, scoring, and a pull-tab, all of which are highly technical die-cutting techniques. Read the full story by clicking the button below.
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