Magneto-dielectric substrate, circuit material, and assembly having the same

Patent metadata

Field	Value
Publication number	US-2016113113-A1
Application number	US-201514882967-A
Country	US
Kind code	A1
Filing date	Oct 14, 2015
Priority date	Oct 15, 2014
Publication date	Apr 21, 2016
Grant date	—

Abstract

In an embodiment, a magneto-dielectric substrate comprises a dielectric polymer matrix; and a plurality of hexaferrite particles dispersed in the polymer matrix in an amount and of a type effective to provide a magneto-dielectric substrate having a magnetic constant of greater than or equal to 2.5 from 0 to 500 MHz, or 3 to 8 from 0 to 500 MHz; a magnetic loss of less than or equal to 0.1 from 0 to 500 MHz, or 0.001 to 0.05 over 0 to 500 MHz; and a dielectric constant of 1.5 to 8 or 2.5 to 8 from 0 to 500 MHz.

First claim

I/We claim:

1 . A magneto-dielectric substrate, comprising:
a thermoset polymer matrix; and a plurality of hexaferrite particles dispersed in the polymer matrix in an amount and of a type effective to provide the magneto-dielectric substrate having
a magnetic constant of greater than or equal to 2.5 from 0 to 500 MHz, or 3 to 8 from 0 to 500 MHz,
a magnetic loss of less than or equal to 0.1 from 0 to 500 MHz, or 0.001 to 0.05 over 0 to 500 MHz; and
a dielectric constant of 1.5 to 8 or 2.5 to 8 from 0 to 500 MHz.

2 . The magneto-dielectric substrate of claim 1 , wherein the magneto-dielectric substrate further has at least one of
a dielectric loss of less than 0.01 or less than 0.005 over 0 to 500 MHz; a UL94 V1 rating measured at a thickness of 1.6 mm; and a peel strength to copper of 3 to 7 pli measured in accordance with IPC test method 650, 2.4.9.

3 . The magneto-dielectric substrate of claim 1 , wherein the plurality of hexaferrite particles is present in the magneto-dielectric substrate in an amount of 5 to 60 vol %, or 10 to 50 vol %, or 15 to 45 vol %, based on the total volume of the magneto-dielectric substrate.

4 . The magneto-dielectric substrate of claim 1 , wherein the polymer matrix comprises 1,2-polybutadiene, polyisoprene, polybutadiene-polyisoprene copolymers, polyetherimide, polyimide, polyamidimide, or a combination comprising at least one of the foregoing.

5 . The magneto-dielectric substrate of claim 1 , wherein the polymer matrix comprises a polybutadiene and/or a polyisoprene;
optionally an ethylene-propylene liquid rubber having a weight average molecular weight of less than or equal to 50,000 g/mol as measured by gel permeation chromatography based on polycarbonate standards; optionally, a dielectric filler; and optionally, a flame retardant.

6 . The magneto-dielectric substrate of claim 1 , wherein the plurality of hexaferrite particles comprises Sr, Ba, Co, Ni, Zn, V, Mn, or a combination comprising one or more of the foregoing.

7 . The magneto-dielectric substrate of claim 1 , wherein the plurality of hexaferrite particles comprises Ba and Co.

8 . The magneto-dielectric substrate of claim 1 , wherein the plurality of hexaferrite particles comprises a silane coating.

9 . The magneto-dielectric substrate of claim 1 , further comprising a fibrous reinforcing layer comprising woven or non-woven fibers.

10 . The magneto-dielectric substrate of claim 9 , wherein the fibers comprise glass fibers, ferrite fibers, ferrite alloy fibers, cobalt fibers, cobalt alloy fibers, iron fibers, iron alloy fibers, nickel fibers, nickel alloy fibers, polymer fibers comprising particulate ferrite, a particulate ferrite alloy, particulate cobalt, a particulate cobalt alloy, particulate iron, a particulate iron alloy, particulate nickel, a particulate nickel alloy, or a combination comprising at least one of the foregoing.

11 . A method of making the magneto-dielectric substrate of claim 1 , the method comprising
dispersing the plurality of hexaferrite particles in a curable polymer matrix composition to form a dispersed composition; forming a layer from the dispersed composition; and curing the curable polymer matrix composition to form the magneto-dielectric substrate.

12 . The method of claim 11 , further comprising impregnating a fibrous reinforcing layer with the dispersed composition; and
partially curing the polymer matrix composition of the layer to provide a prepreg.

13 . A circuit material, comprising
a conductive layer; and the magneto-dielectric substrate of claim 1 disposed on the conductive layer.

14 . A method of making the circuit material of claim 13 , the method comprising
dispersing the plurality of hexaferrite particles in a curable polymer matrix composition to form a dispersed composition; forming a layer from the dispersed composition; disposing the layer on the conductive layer; and curing the curable polymer matrix composition.

15 . The method of claim 14 , wherein the curing is by laminating.

16 . The method of claim 14 , wherein the forming comprises impregnating a fibrous reinforcing layer with the dispersed composition; and partially curing the curable polymer matrix composition to provide a prepreg before disposing the prepreg on the conductive layer.

17 . A method of making the circuit of claim 14 , further comprising patterning the conductive layer.

18 . A circuit comprising the circuit material of claim 13 .

19 . An antenna comprising the circuit of claim 18 .

20 . An RF component comprising the magneto-dielectric substrate of claim 1 .

Assignees

• Rogers Corp

Inventors

• Sethumadhavan Murali
• Horn Iii Allen F
• Sprentall Karl Edward
• White Michael

Classifications

• H05K3/043

  by using a moving tool for milling or cutting the conductive material · CPC title

• H05K1/0353 Primary

  consisting of two or more materials, e.g. two or more polymers, polymer + filler, + reinforcement · CPC title

• H05K3/061

  Etching masks · CPC title

• H01F17/0006

  Printed inductances (printed coils for dynamo-electric machines H02K3/26; printed circuits H05K) · CPC title

• D06M11/83

  with metals; with metal-generating compounds, e.g. metal carbonyls; Reduction of metal compounds on textiles · CPC title