A tantalum polymer capacitor is a higher performing capacitor. It is a parallel plate capacitor with two conductive surfaces separated by a distance, with a dielectric in between the two plates. Tantalum polymer capacitors are desirable because of their high reliability and longer life spans of service. They have become the preferred capacitor of choice for current surface mount technology (SMT) capacitors.

The tantalum pentoxide, which is the dielectric used in between the two conducting surfaces, is applied to the conducting surfaces or plates of the capacitor through an advanced electrolytic process. The electrolytic process allows for small distances between the two conducting surfaces, thus increasing the effective capacitance. This process technology has advanced the effectiveness and efficiency of capacitors such that tantalum capacitors exhibit three times more capacitance per volume than general aluminum capacitors. This improvement has become desirable for modern electronic systems that require better capacitors with smaller and smaller form factors.

A key metric for capacitors is the equivalent series resistance (ESR), which summarizes all the ohmic or resistive losses of the capacitor.  Although tantalum capacitors provided low or good ESR performance, a new technology - conductive polymers were developed to provide a lower ESR value that exhibited conductivity characteristics close to that of metals. This low ESR value is a desirable trait in the capacitor. The robust dielectric behavior of the tantalum together with the low ESR of the conducting polymers make the tantalum polymer capacitor an effective choice for the demands required in today’s technology.  Tantalum polymer capacitors are often used on a variety of printed circuit boards found in multiple electronic systems for maintaining robust, low impedance power delivery networks.