Self-aligned coaxial via capacitors

Abstract

The various embodiments of coaxial capacitors are self-aligned and formed in a via, including blind vias, buried vias and plated through holes. The coaxial capacitors are adapted to utilize the plating of a plated via as a first electrode. The dielectric layer is formed to overlie the first electrode while leaving a portion of the via unfilled. A second electrode is formed in the portion of the via left unfilled by the dielectric layer. Such coaxial capacitors are suited for use in decoupling and power dampening applications to reduce signal and power noise and/or reduce power overshoot and droop in electronic devices. For such applications, it is generally expected that a plurality of coaxial capacitors, often numbering in the thousands, will be coupled in parallel in order to achieve the desired level of capacitance.