Solid electrolytic capacitor and method for manufacturing the same.

摘要

A solid electrolytic capacitor comprises a valve metal member (12) having a dielectric oxide film (13) and a conductive underlying layer (14) formed on the member in this order, and a conductive polymer film (16) formed on the conductive underlying layer (14). The conductive polymer film (16) is formed by electrolytic polymerization of a polymerizable monomer contained in an aqueous solution containing a support electrolyte and a phosphate. By the presence of the phosphate in the aqueous solution, phosphate ions dissociated from the phosphate are adsorbed on the dielectric film (13) during the course of the electrolytic polymerization. Thus, the humidity resistance of the dielectric oxide film is improved, resulting in improvements in the capacitance and loss of the capacitor under high temperature and high humidity conditions. A fabrication method of the capacitor is also described.