Thin film capacitor performance and design calculation

What is a thin film capacitor?

The thin-film capacitors are thin — on the order of 0.1 μm to < 10 μm. The edge dimensions are dependent on the desired capacitance value and on the capacitance density, whose BOCA value is given by the dielectric constant and breakdown voltage, as defined in Chapter 2.

What determines film capacitor performance?

Film capacitor performance is governed by the dielectric film and metallization end connections. Advances in both are required to increase the energy density that ultimately determines the size and weight. This paper is about biaxially oriented isotactic polypropylene film (BOPP) that forms the main insulation in these capacitors.

What factors affect the design and fabrication of thin-film capacitors?

The design and fabrication of thin-film capacitors for a particular application depend upon a number of variables, such as required capacitance density, breakdown voltage, leakage current density, frequency of operation, Q-factor, and environmental conditions.

What is a thin film decoupling capacitor?

Thin-film, high-Dk, embedded capacitor material (1300 nF/inch2 or 200 nF/cm2) enables the embedding of decoupling capacitors for power supply to high-speed circuits. Measured data shows loss tangent <0.02 and breakdown voltage 40V.

How do you calculate the life of a film capacitor?

For the life of a film capacitor, the Mean Time To Failure(MTTF), which is calculated by the inverse of the failure rate, is used as the basis for the life calculation. If a capacitor is used at high temperatures, its service life will be shortened due to thermal deterioration.

Why is thin-film dielectric a good choice for decoupling capacitors?

The low inductance of thin-film dielectrics is well-suited for decoupling capacitors for low-impedance power supplied to high-speed digital circuits. It enables fast switching of required large currents at low supply voltages, and with reduced EMI.