A simple sintered anode model of four particles, four necks, and one pore can be used to convey design considerations for selecting a powder. For a given rated voltage, a formation voltage is applied to the anode to form the dielectric. The necks will become smaller due to the inward growth of the dielectric. A smaller neck may equate to higher resistance. As current flows, heat will be generated. Too much heat can convert amorphous dielectric to crystalline dielectric and, thus, increase leakage. The pore will become smaller due to the outward growth of the dielectric. Designers optimize the electrical performance selecting a Tantalum powder size depending on capacitor rated voltage. The higher the rated voltage, the bigger the particles are designed to allow a stable Tantalum Pentoxide growth.