Self-healing solid tantalum electrolytic capacitors with low ESR, high-frequency performance, and simple fabrication

This study aims to develop a novel self-healing polymer tantalum electrolytic capacitor with low equivalent series resistance (ESR), high-frequency performance, and a simple preparation method. The capacitor was designed based on a Metal/Insulator/Conductive Polymer/Metal structure, where a copper layer was electroplated onto the surface of PEDOT polymer tantalum electrolytic capacitors (P-PTECs). The effect of electroplating conditions on the electrical properties of the tantalum electrolytic capacitors (TECs) was comprehensively studied. The results demonstrated that incorporating a copper metal layer into the structure of the capacitors significantly reduced the ESR of TECs. By employing an electroplating voltage of 2 V, a current density of 2 A/dm 2 , and a plating time of 5 min, the ESR of the capacitor was minimized to 27 mΩ. Moreover, the Dissipation Factor (DF) of the capacitor was also enhanced. The utilization of a conductive polymer as the cathode layer provided the capacitors with self-healing characteristics that significantly decreased the leakage current (LC) in the capacitor. Furthermore, the Metal/Insulator/Conductive Polymer/Metal structure fabrication method provided an inventive solution for incorporating thin-film tantalum electrolytic capacitors onto active silicon substrates, opening up possibilities for future ultra-thin and high-density capacitor integration.