Embedded passives are a novel technology that enables the replacement of traditional surface mounted capacitors and resistors by embedding them inside the printed wiring boards (PWBs).

Embedded passives can take many different forms, from laminates to ceramics to polymers. DuPont core competencies in polymer science, laminate technology and ceramics allow DuPont to build an extensive embedded passive portfolio.

The DuPont™ Interra™ brand of embedded passives consists of both resistive and conductive products and is allowing customers to take advantage of the embedded passive value.

Why use Embedded Passives?

There are three principle reasons to use embedded passives:

1. Reduce costs
2. Improve performance
3. Reduce the product size

In many applications cost reduction advantages can be realized by using embedded passives. Typically the advantage is gained when an application has a sufficiently high passive density where the total cost of materials and processing are less than that of traditional surface mounted technology. For instance, RF modules used in cell phones benefit greatly from using embedded capacitors since they have a very high passive density and a majority of capacitors can be embedded.

When the capacitor is moved from a surface location a distance away from the active component to directly underneath the component, the performance is improved. Direct performance gains include reducing the current loop and improving speed of a circuit.

Because the surface mounted components are now being moved inside the printed wiring board, there is an increase of available real estate. This increase in free space can either be used to add more functionality to a product or to reduce the overall size of a product. Embedded passives have been used to reduce the size of modules anywhere from 25% to 75%.