Ceramic is the dielectric material used in the manufacture of ceramic capacitor.  Dielectrics are the insulating material between the plates of capacitors.  This material is chosen for its ability to permit electrostatic attraction and repulsion to take place across it.  Ceramic is an excellent dielectric material because it is a poor conductor of electricity while being an effective supporter of electrostatic fields.

ceramic capacitors are manufactured using a tape casting process wherein thin layers of conductive electrodes are separated by a dielectric layer, and a kind of multi-layer “sandwich” is formed to create a ceramic capacitor with a very large surface area in a very compact size.  Recently, the combination of nickel electrodes and the ability to cast very thin layers has allowed the capacitance range of ceramic capacitors to exceed more than 100μF in an 1812 package, using X5R dielectric material.  With the ability to stack hundreds of layers to form a single high-density, high-capacitance multilayer ceramic capacitor, new application opportunities, that were previously the sole domain of tantalum capacitors, are now available for ceramic capacitors.  One of the driving forces for the increased capacitance values in ceramic capacitors was the tantalum shortage of 2000.

Prior to the use of nickel electrode systems, Palladium (Pd) and Silver (Ag) were the most common electrode materials.  This precious metal became cost prohibitive when making very high-capacitance, high-layer count ceramic capacitors.  Palladium and silver are still widely used for ceramic capacitors with lower capacitance values.

There are now a number of ceramic materials and compositions that are used in ceramic capacitors.  These include ceramic COG (NPO), ceramic X5R, and ceramic Y5V.

Disc ceramic capacitors combine a solid body of high-temperature, ceramic-resistive material with bonded metal contacts.  Tecate offers disc type ceramic capacitors in a number of dielectrics and various lead configurations.

Multilayer ceramic capacitors are constructed using an alternating stack of conductors and insulators, connected on both sides by a common termination.  The standard termination material for ceramic capacitors is nickel barrier with a 100% tin coating to comply with the latest RoHS standards.  These ceramic capacitors are available in radial leaded conformal coated packages or the more popular surface mount configuration that is well suited for high-speed pick and place mounting.  Surface mount ceramic capacitors are available in sizes ranging from 0201 to 2225.  Tecate also offers larger-sized ceramic capacitors on a custom basis.

ceramic capacitor: COG (NPO) is a high-Q, low-K, temperature-compensating type of dielectric with stable electrical properties under varying voltage, temperature, frequency, and time.  It is suitable for circuits that require low loss, as well as timing and tuning applications.  NPO ceramic capacitors offer the best capacitance precision and are available in 1%, 5%, and 10% tolerances.

ceramic capacitor: X5R dielectric has moderate, “mid” K values and is temperature stable.  It shows moderate change in electrical properties under changing temperature, voltage, and frequency.  It is suitable for bypassing, coupling, and frequency discrimination circuit applications.  X5R ceramic capacitors show no more than a 15% capacitance deviation over the temperature range -55°C to +85°C.

ceramic capacitor: Y5V dielectric is a Class III dielectric that exhibits a maximum capacitance change of +22%, -82% over an operating temperature range of +30°C to +85°C in ceramic capacitors.

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