IP Library Granted Patent US 12,250,767
Granted Patent B2
US 12,250,767 · App. 18/471,816 · Granted Mar 11, 2025

Dielectric substrate and method of forming the same

Inventors: Jennifer Adamchuk (Marlborough, MA); Gerard T. Buss (Bedford, NH); Theresa M. Besozzi (Milford, MA)
Assignee: VERSIV COMPOSITES LIMITED
H05K1/0373H05K1/05H05K1/09H05K2201/0358
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Quick Facts
Patent No.
US 12,250,767
App. No.
18/471,816
Granted
Mar 11, 2025
Kind
B2
Abstract

The present disclosure relates to a dielectric substrate that may include a polyimide layer and a first filled polymer layer overlying the polyimide layer. The first filled polymer layer may include a resin matrix component, and a first ceramic filler component. The first ceramic filler component may include a first filler material. The first filler material may further have a mean particle size of at not greater than about 10 microns.

Claims (36)

1. A dielectric substrate comprising:

a polyimide layer and

a first filled polymer layer overlying the polyimide layer, wherein the first filled polymer layer comprises a first resin matrix component; and

a first ceramic filler component, wherein the first ceramic filler component comprises a first filler material, wherein the first filler material further comprises a mean particle size of at not greater than about 10 microns, and

wherein the first filler material further comprises an average surface area of not greater than about 10 m 2 /g.

2. The dielectric substrate of claim 1 , wherein the first filler material comprises a silica-based compound.

3. The dielectric substrate of claim 1 , wherein the first resin matrix component comprises a perfluoropolymer.

4. The dielectric substrate of claim 1 , wherein the content of the first resin matrix component is at least about 45 vol. % and not greater than about 63 vol. % for a total volume of the first filled polymer layer.

5. The dielectric substrate of claim 1 , wherein the content of the first ceramic filler component is at least about 30 vol. % and not greater than about 57 vol. % for a total volume of the first filled polymer layer.

6. The dielectric substrate of claim 1 , wherein the content of the first filler material is at least about 80 vol. % and not greater than about 100 vol. % for a total volume of the first ceramic filler component.

7. The dielectric substrate of claim 1 , wherein the first ceramic filler component further comprises a second filler material.

8. The dielectric substrate of claim 7 , wherein the second filler material of the first ceramic filler component comprises a high dielectric constant ceramic material.

9. The dielectric substrate of claim 7 , wherein a particle size distribution of the silica filler material of the second ceramic filler component comprises a D 10 of at least about 0.2 microns and not greater than about 1.6.

10. The dielectric substrate of claim 7 , wherein the second filler material comprises a silica-based compound.

11. The dielectric substrate of claim 1 , wherein the dielectric substrate further comprises a second filled polymer layer underlying the polyimide layer, wherein the second filled polymer layer comprises a second resin matrix component; and a second ceramic filler component, wherein the second ceramic filler component comprises a silica filler material, wherein the first filler material further comprises a mean particle size of at not greater than about 10 microns, and wherein the first filler material further comprises an average surface area of not greater than about 10 m 2 /g.

12. The dielectric substrate of claim 1 , wherein the dielectric substrate comprises a dissipation factor (5 GHZ, 20% RH) of not greater than about 0.005.

13. The dielectric substrate of claim 1 , wherein the dielectric substrate comprises a porosity of not greater than about 10 vol. %.

14. A copper-clad laminate comprising a copper foil layer, and a dielectric substrate overlying the copper foil layer, wherein the dielectric substrate comprises:

a polyimide layer and a first filled polymer layer overlying the polyimide layer,

wherein the first filled polymer layer comprises a first resin matrix component; and a first ceramic filler component,

wherein the first ceramic filler component comprises a first filler material, and

wherein the first filler material further comprises a mean particle size of at not greater than about 10 microns, and

wherein the first filler material further comprises an average surface area of not greater than about 10 m 2 /g.

15. The copper-clad laminate of claim 14 , wherein the copper-clad laminate comprises a peel strength between the copper foil layer and the dielectric substrate of at least about 6 lb/in.

16. The copper-clad laminate of claim 14 , wherein the copper-clad laminate comprises a porosity of not greater than about 10 vol. %.

17. A printed circuit board comprising a copper-clad laminate, wherein the copper-clad laminate comprises:

a copper foil layer, and a dielectric substrate overlying the copper foil layer, wherein the dielectric substrate comprises:

a polyimide layer and a first filled polymer layer overlying the polyimide layer,

wherein the first filled polymer layer comprises a first resin matrix component; and a first ceramic filler component,

wherein the first ceramic filler component comprises a first filler material, and

wherein the first filler material further comprises a mean particle size of at not greater than about 10 microns, and

wherein the first filler material further comprises an average surface area of not greater than about 10 m 2 /g.

18. The printed circuit board of claim 17 , wherein the printed circuit board comprises a peel strength between the copper foil layer and the dielectric substrate of at least about 5 lb/in.

19. The printed circuit board of claim 17 , wherein the printed circuit board comprises a porosity of not greater than about 10 vol. %.

20. The printed circuit board of claim 17 , wherein the silica filler material of the first ceramic filler component comprises a particle size distribution span (PSDS) of not greater than about 8, where PSDS is equal to (D 90 −D 10 )/D 50 , where D 90 is equal to a D 90 particle size distribution measurement of the silica filler material, D 10 is equal to a D 10 particle size distribution measurement of the first filler material, and D 50 is equal to a D 50 particle size distribution measurement of the first filler material.

21. The printed circuit board of claim 17 , wherein the dielectric substrate comprises a dissipation factor (5 GHz, 20% RH) of not greater than about 0.005.

Assignments (3)
CHANGE OF NAME Recorded Jul 31, 2024
From: SAINT-GOBAIN PERFORMANCE PLASTICS IRELAND LIMITED
To: VERSIV COMPOSITES LIMITED
Reel/Frame 068217/0484 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 25, 2024
From: SAINT-GOBAIN PERFORMANCE PLASTICS CORPORATION
To: SAINT-GOBAIN PERFORMANCE PLASTICS IRELAND LIMITED
Reel/Frame 068676/0703 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 19, 2024
From: ADAMCHUK, JENNIFER; BUSS, GERARD T.; BESOZZI, THERESA M.
To: SAINT-GOBAIN PERFORMANCE PLASTICS CORPORATION
Reel/Frame 067165/0174 →
Continuity (4)
Continuation 18157918 · Jan 23, 2023
Continuation 17443390 · Jul 26, 2021
Provisional Application 63057670 · Jul 28, 2020
Related Publication 20240023242A1 · Jan 18, 2024
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