Monolithic multilayer ceramic capacitors (MLCC) are commonly used for decoupling purposes because they are polarity-free, have low impedance, and are compact in various capacitance and package sizes.
The capacity density of ceramic capacitors has been improved to provide the smallest packages with a sufficient level of decoupling capacitance. In recent years, manufacturers have developed dielectrics so that even 10 μF capacitors can be found in 0402 packages up to 6.3 V in rated voltage.
However, the increased density means complications in capacitor characteristics. There are several factors that can have a significant impact on the effective capacitance of a decoupling capacitor in an application, the most significant ones being DC bias, AC bias, and temperature.