Matching embedded capacitor dielectrics to applications

All capacitor dielectric materials, whether used for discrete or embedded applications, can be grouped into two general categories: paraelectric and ferroelectric. Ferroelectrics generally exhibit much higher dielectric constants, but are also less stable with regard to temperature, frequency, voltage, time and film thickness. There are dozens of each of these materials that have been used in discrete capacitors and about ten that are either available for use in embedded capacitors or will soon be marketed for that purpose. The commercialized materials can be broken down into four sub‐categories: thick‐film polymers, ferroelectric powder in polymer binders, thin‐film paraelectrics, and thick‐film ferroelectrics. These four classifications are evaluated with regard to their electrical performance, ease of fabrication, and suitability for specific applications.