Matsushita Electric Industrial Co., Ltd.

Yasunobu Tsuji

Emiko Igaki

Chiharu Hayashi

Masakazu Tanahashi

Takahiro Hamada

Keiji Onishi

Kazuo Eda

Yutaka Taguchi

Kazuo Kawahito

Hisataka Kato

Hiroshi Shimada

Yoshiki Hashimoto

Mitsuo Terada

Katsuyuki Miyauchi

Yoshihiko Tsujikawa

A solid electrolytic capacitor includes an anode element made of a valve action metal, a dielectric oxide film formed on a surface of the anode element, a solid electrolytic layer formed on a surface of the dielectric oxide film, and a cathode layer formed on a surface of the solid electrolytic layer. The solid electrolytic layer has an iron concentration not greater than 100 ppm. Alternatively or in combination therewith, a weight fraction of residues in the solid electrolytic layer is smaller than 5 wt %. The polymerization residue is an oxidizing agent and a monomer that is produced when such solid electrolytic layer is formed.

Solid electrolytic capacitor

The present invention provides a method of producing an electrolytic capacitor including a porous anode and a solid electrolyte made of a conductive polymer, which can improve coating properties of the conductive polymer on an external surface of the porous anode and productivity. By controlling a polymerization rate, it is possible to sufficiently coat the external surface of the porous anode and fill inner spaces of a lot of pores of the porous anode with the conductive polymer with less numbers of polymerization in comparison with a method of the prior art, thereby obtaining an electrolytic capacitor with small leak current and high reliability.

Method of producing electrolytic capacitor

The present invention provides a method for producing an electrolytic capacitor including a porous body of a valve metal, an oxide film on a surface of the valve metal, and a conductive polymer layer on a surface of the oxide film. The step of forming the conductive polymer layer on the surface of the oxide film includes the steps of dipping the porous body in a monomer solution; lifting the porous body from the monomer solution and dipping the porous body in an oxidizing solution; and lifting the porous body from the oxidizing solution and allowing the porous body to stand. In the step of dipping the porous body in the oxidizing solution, a period for which the porous body is dipped in the oxidizing solution is equal to or shorter than a period in which 30% of the monomer contained in pores of the porous body diffuses and flows into the oxidizing solution. Alternatively, the volume of the oxidizing solution can be less than three times that of the porous body. The above method can be performed by replacing the monomer solution and the oxidizing solution with each other. Furthermore, a temperature of the porous body is maintained at a low temperature (e.g., 10.degree. C. or less) in the step of dipping the porous body in the oxidizing solution.

Electrolytic capacitor and method for producing the same

A surface acoustic wave device including a dielectric substrate having an input electrode and an output electrode and a grounding electrode on a first surface of the dielectric substrate, and an outer electrode on a second surface of the dielectric substrate; and a surface acoustic wave element having an electrode pad and a comb-shaped electrode disposed on a first surface of the surface acoustic wave element. The surface acoustic wave element is bonded to the dielectric substrate via a metal bump and a conductive resin formed on the electrode pad. The surface acoustic wave device further includes an insulating resin deposited on the periphery of the metal bump, and a guard layer shorter in height than the surface acoustic wave element formed adjacent the surface acoustic wave element on the first surface of the dielectric substrate.

Surface acoustic wave devices having a guard layer

Growing community of inventors

Katano, Japan

Yasunobu Tsuji