Because the capacitance value of solid-state tantalum capacitors maintains stable capacitance characteristics with respect to temperature and bias voltage, selection criteria include only tolerance, step-down over the operating temperature range, and maximum ESR.
A major disadvantage of solid polymer electrolyte technology is that these tantalum capacitors are more susceptible to high temperatures in lead-free soldering processes. Typically, the manufacturer will specify that the capacitor must not be exposed to more than three solder cycles. Neglecting this requirement in the assembly process can lead to long-term reliability problems.