Abstract:
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.
Abstract:
A method for maintaining quality of monomer during a coating process for intrinsically conductive polymer which suppresses unwanted by-products. A neutralization process using a base or anion exchange resin is used batch-wise or continuous.
Abstract:
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 ration 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 of pure water. The process produces low ESR and low leakage valve metal capacitors with conductive polymer cathodes.
Abstract:
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 b y weight. The solvent content in the polymer precursor solution is from 0 to 99 % by weight.
Abstract:
An improved capacitor with an anode (11) with an anode wire and an oxide layer (12) on the surface of the anode (11). A cathode layer is exterior to the oxide layer. A carbon conductive layer (14) is exterior to the cathode layer wherein the cathode layer comprises 5-75 wt% resin and 25-95 wt% conductor. The conductor has carbon nanotubes. An anode lead is in electrical contact with the anode wire and a cathode lead is in electrical contact with the carbon conductive layer (14).
Abstract:
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 polymer layer (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.
Abstract:
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 ration 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 of pure water. The process produces low ESR and low leakage valve metal capacitors with conductive polymer cathodes.
Abstract:
A process for preparing a solid electrolytic capacitor comprising application of a non-ionic polyol prior to application of a conducting polymer layer.
Abstract:
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.
Abstract:
A capacitor has first planer internal electrodes in electrical contact with a first external termination. Second planer internal electrodes are interleaved with the first planer internal electrodes wherein the second planer internal electrodes are in electrical contact with a second external termination. A dielectric is between the first planer internal electrodes and the second planer internal electrodes and at least one of the external terminations comprises a material selected from a polymer solder and a transient liquid phase sintering adhesive.