Non-reciprocal circuit element and communication device
AssigneeMurata Manufacturing Co., Ltd.
InventorJunpei Isoda
Life of this patent
Estimating the term…
Abstract
A non-reciprocal circuit element has matching capacitors, each disposed between an I/O port and ground. Each matching capacitor has a dielectric substrate and first buffer layers, second buffer layers, and main lead layers formed on both surfaces of the dielectric substrate by dry thin-film deposition, in that order. For example, a Ni—Cr alloy, a Ni—Cu alloy, and Ag are used for the first buffer layers, the second buffer layers, and the main lead layers, respectively. The matching capacitors can solve the problems arising from the electrodes of known capacitors, and thus the non-reciprocal circuit element and communication devices using the capacitors can have excellent electrical characteristics.
Claims13
A non-reciprocal circuit element comprising:
- a ferrite body;
- a magnet providing a magnetic field to said ferrite body;
- a plurality of center electrodes disposed on said ferrite body, each of said center electrodes having an I/O port at one end and another end connected to a around electrode;
- matching capacitors, each disposed between one of said P0 ports and said around electrode, each matching capacitor comprising a dielectric substrate with two opposed main surfaces, and first buffer layers, second buffer layers, and main lead layers, in that order, formed on both of said main surfaces of the dielectric substrate, said avers being thin-film layers;
- wherein
- the first buffer layers are formed of a material which adheres to the dielectric substrate, the second buffer avers are formed of a material capable of preventing solder from diffusing into the dielectric substrate, and the main lead layers are formed of a solderable conductive material;
- and
- the second buffer layers are formed of a material selected from the group consisting of Ni—Cu, Ni—Ag, Ni—Au, Ni—Ti, alloys thereof, and alloys of the materials of the first buffer layers and the main lead layers.
A matching capacitor for a non-reciprocal circuit element, comprising:
- a dielectric substrate with two opposed main surfaces, and first buffer layers, second buffer layers, and main lead layers, in that order, formed on both of said main surfaces of the dielectric substrate, said avers being thin-film layers;
- wherein
- the first buffer layers are formed of a material which adheres to the dielectric substrate, the second buffer layers are formed of a material capable of preventing solder from diffusing into the dielectric substrate, and the main lead layers are formed of a solderable conductive material;
- and
- the second buffer layers are formed of a material selected from the group consisting of Ni—Cu, Ni—Ag, Ni—Au, Ni—Ti, alloys thereof, and alloys of the materials of the first buffer layers and the main lead layers.
A method of manufacturing a matching capacitor for a non-reciprocal circuit element, comprising the steps of:
- providing a dielectric substrate having two opposed main surfaces, and
- forming first buffer layers, second buffer layers, and main lead layers, in that order, on both surfaces of the dielectric substrate, by dry thin-film deposition;
- wherein p1 the first buffer layers are formed of a material which adheres to the dielectric substrate, the second buffer layers are formed of a material capable of preventing solder from diffusing into the dielectric substrate, and the main lead layers are formed of a solderable conductive material;
- and
- the second buffer layers are formed of a material selected from the group consisting of Ni—Cu, Ni—Ag, Ni—Au, Ni—Ti, alloys thereof, and alloys of the materials of the first buffer layers and the main lead layers.
Dependencies are inferred from the claim text.