摘要:
The present invention relates to a method for making a solid electrolytic capacitor having a low equivalent series resistance by impregnating a porous capacitor pellet with conductive polymer. An oxidized pellet is dipped in a high concentration conductive polymer solution to deposit the polymer in doped (conductive) form. The solution also contains a crosslinking agent to prevent redissolution of the polymer when the pellet is re-dipped. After dipping, the solvent in the polymer solution is evaporated and a conductive film formed. In order to evaporate the solvent quickly, the solvent should have a boiling point of 80-220° C. and preferably a boiling point of 100-150° C. The conductive polymer film has a low resistivity (less than 1 ohm-cm, preferably less than 0.2 ohm-cm).
摘要:
Conductive polymers are formed with a self-regenerating oxidant system made with a reversibly reducible metal salt at amounts sufficient to polymerize a cyclic monomer through oxidation and leave a reduced metal ion, and an oxidant in an amount sufficiently small and under conditions sufficient to oxidize the reduced metal ion but avoid oxidation or degradation of the polymer. The most preferred combination of agents includes ferric nitrate and a small amount of ammonium nitrate at a pH within the range of 2 to 7.
摘要:
An improved capacitor is provided wherein the improved capacitor has improved ESR. The capacitor has a fluted anode and an anode wire extending from the fluted anode. A dielectric is on the fluted anode. A conformal cathode is on the dielectric and a plated metal layer is on the carbon layer.
摘要:
A solid electrolytic capacitor with an anode and a dielectric on the anode. A cathode is on the dielectric and a conductive coating on said dielectric. A cathode lead is electrically connected to the conductive coating by an adhesive selected from the group consisting of a transient liquid phase sinterable material and polymer solder.
摘要:
A process for forming a capacitor. The process includes providing an anode; providing a dielectric on the anode; exposing the anode to a polymer precursor solution comprising monomer, conjugated oligomer and optionally solvent and polymerizing the polymer precursor. The ratio between monomer and conjugated oligomer ranges from 99.9/0.1 to 75/25 by weight. The solvent content in the polymer precursor solution is from 0 to 99% by weight.
摘要:
A capacitor is described with an NbO anode. The capacitor has an NbO anode and an NbO anode lead extending from the NbO anode. A dielectric is on the NbO anode and a conductor is on the dielectric.
摘要:
Embedded capacitors comprise a bimetal foil (500) that includes a first copper layer (205) and an aluminum layer (210) on the first copper layer. The aluminum layer has a smooth side adjacent the first copper layer and a high surface area textured side (215) opposite the first copper layer. The bimetal foil further includes an aluminum oxide layer (305) on the high surface area textured side of the aluminum layer, a conductive polymerlayer (420) on the aluminum oxide layer, and a second copper layer (535) overlying the aluminum oxide layer. The bimetal foil may be embedded in a circuit board (700) to form high value embedded capacitors.
摘要:
An intrinsically conductive polymer is prepared with a chemical oxidative process. The polymer is prepared by first dipping or coating a substrate with an Fe(III)-containing oxidizer solution and drying. The substrate is then dipped or coated with a monomer, such as 3,4-ethylenedioxythiophene solution, and reacted to form the conductive polymer. The monomer is dissolved in a solvent in which it has a high solubility but in which the Fe(III)-containing oxidizer has low solubility. This minimizes cross-contamination of the monomer and oxidizer dipping solutions thereby making this process suitable for high volume production. Dissolving the monomer in a solvent allows control over the stoichiometric ratio of monomer to oxidizer and prevents an excess of monomer thereby facilitating the removal of any unreacted monomer by water. The substrate is then dipped in an aqueous solution of para-toluenesulfonic acid to facilitate the removal of Fe(II) byproducts by enhancing their solubility in water and then the substrate may be washed with an aqueous solution or pure water. The process produces low ESR and low leakage valve metal capacitors with conductive polymer cathodes.
摘要:
An electrolytic solution comprising glycerine and dibasic potassium phosphate. The electrolytic solution has a water content of less than 1000 ppm and is prepared by mixing the glycerine and the dibasic potassium phosphate and then heating to about 150 to 180.degree. C. for about 1 to 12 hours. A method of anodizing a metal comprising forming a film on the metal with an electrolytic solution comprising glycerine and dibasic potassium phosphate. The metal is preferably a valve metal, such as tantalum, and the film is formed at a temperature of 150.degree. C. or higher.
摘要:
Acid-doped, polyaniline-based polymers are formed into fibers, films, and coatings with a solvent of at least one bicyclic terpene. Such a solvent system is characterized by a drying temperature of less than 150.degree. C. and a relatively low toxicity.