Molding composition and method, and molded article
View Patent ↗A molding composition suitable for encapsulating solid state devices includes an epoxy resin, a hardener, a poly(arylene ether) resin comprising less than 5 weight percent of particles greater than 100 micrometers, and about 70 to about 95 weight percent of a silica filler, based on the total weight of the composition. After curing, the composition exhibits improved increased copper adhesion and reduced shrinkage compared to conventional molding compositions.
1. A curable composition, comprising:
an epoxy resin;
a hardener;
a poly(arylene ether) resin comprising less than 5 weight percent of particles greater than 100 micrometers; and
about 70 to about 95 weight percent of a silica filler, based on the total weight of the curable composition.
2. The curable composition of claim 1 , wherein the epoxy resin comprises an epoxy resin having a softening point of about 25° C. to about 150° C.
3. The curable composition of claim 1 , wherein the epoxy resin is selected from aliphatic epoxy resins, cycloaliphatic epoxy resins, bisphenol-A epoxy resins, bisphenol-F epoxy resins, phenol novolac epoxy resins, cresol-novolac epoxy resins, biphenyl epoxy resins, polyfunctional epoxy resins, naphthalene epoxy resins, divinylbenzene dioxide, 2-glycidylphenylglycidyl ether, dicyclopentadiene-type epoxy resins, multi aromatic resin type epoxy resins, and combinations thereof.
4. The curable composition of claim 1 , wherein the epoxy resin comprises a monomeric epoxy resin and an oligomeric epoxy resin.
5. The curable composition of claim 1 , wherein the epoxy resin comprises a biphenyl epoxy and an epoxidized cresol novolac.
6. The curable composition of claim 1 , comprising about 70 to about 98 parts by weight of the epoxy resin per 100 parts by weight total of the epoxy resin and the poly(arylene ether) resin.
7. The curable composition of claim 1 , wherein the hardener is selected from novolac type phenol resins, aralkyl type phenol resins, dicyclopentadiene type phenol resins, terpene modified phenol resins, biphenyl type phenol resins, bisphenols, triphenylmethane type phenol resins, and combinations thereof.
8. The curable composition of claim 1 , wherein the hardener comprises a novolac type phenol resin.
9. The curable composition of claim 1 , comprising about 10 to about 100 parts by weight of hardener per 100 parts by weight total of the epoxy resin and the poly(arylene ether) resin.
10. The curable composition of claim 1 , wherein the poly(arylene ether) resin comprises less than 1 weight percent of particles greater than 100 micrometers.
11. The curable composition of claim 1 , wherein the poly(arylene ether) resin comprises less than 1 weight percent of particles greater than 60 micrometers.
12. The curable composition of claim 1 , wherein the poly(arylene ether) resin comprises a plurality of repeating units having the structure
wherein each occurrence of Q 2 is independently selected from hydrogen, halogen, primary or secondary C 1 -C 12 alkyl, C 2 -C 12 alkenyl, C 3 -C 12 alkenylalkyl, C 2 -C 12 alkynyl, C 3 -C 12 alkynylalkyl, C 1 -C 12 aminoalkyl, C 1 -C 12 hydroxyalkyl, phenyl, C 1 -C 12 haloalkyl, C 1 -C 12 hydrocarbyloxy, and C 2 -C 12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms; and wherein each occurrence of Q 1 is independently selected from halogen, primary or secondary C 1 -C 12 alkyl, C 2 -C 12 alkenyl, C 3 -C 12 alkenylalkyl, C 2 -C 12 alkynyl, C 3 -C 12 alkynylalkyl, C 1 -C 12 aminoalkyl, C 1 -C 12 hydroxyalkyl, phenyl, C 1 -C 12 haloalkyl, C 1 -C 12 hydrocarbyloxy, and C 2 -C 12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms.
13. The curable composition of claim 1 , wherein the poly(arylene ether) resin has the structure
wherein each occurrence of Q 2 is independently selected from hydrogen, halogen, primary or secondary C 1 -C 12 alkyl, C 2 -C 12 alkenyl, C3-C 12 alkenylalkyl, C2-C 12 alkynyl, C 3 -C 12 alkynylalkyl, C 1 -C 12 aminoalkyl, C 1 -C 12 hydroxyalkyl, phenyl, C 1 -C 12 haloalkyl, C 1 -C 12 hydrocarbyloxy, and C 2 -C 12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms; and wherein each occurrence of Q 1 is independently selected from hydrogen, halogen, primary or secondary C 1 -C 12 alkyl, C 2 -C 12 alkenyl, C 3 -C 12 alkenylalkyl, C 2 -C 12 alkynyl, C 3 -C 12 alkynylalkyl, C 1 -C 12 aminoalkyl, C 1 -C 12 hydroxyalkyl, phenyl, C 1 -C 12 haloalkyl, C 1 -C 12 hydrocarbyloxy, and C 2 -C 12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms; each occurrence of x is independently 1 to about 100; z is 0 or 1; and Y has a structure selected from
wherein each occurrence of R 1 , R 2 , and R 3 is independently selected from hydrogen and C 1 -C 12 hydrocarbyl.
14. The curable composition of claim 1 , wherein the poly(arylene ether) resin comprises at least one terminal functional group selected from carboxylic acid, glycidyl ether, and anhydride.
15. The curable composition of claim 1 , wherein the poly(arylene ether) resin has an intrinsic viscosity of about 0.03 to 1.0 deciliters per gram measured at 25° C. in chloroform.
16. The curable composition of claim 1 , wherein the poly(arylene ether) resin has an intrinsic viscosity of about 0.03 to 0.15 deciliters per gram measured at 25° C. in chloroform.
17. The curable composition of claim 1 , wherein the poly(arylene ether) resin has an intrinsic viscosity of about 0.12 to about 0.30 deciliters per gram measured at 25° C. in chloroform.
18. The curable composition of claim 1 , comprising about 2 to about 30 parts by weight of the poly(arylene ether) resin per 100 parts by weight total of the epoxy resin and the poly(arylene ether) resin.
19. The curable composition of claim 1 , wherein the silica filler comprises a fused silica.
20. The curable composition of claim 1 , wherein the silica filler comprises, based on the total weight of silica filler, about 75 to about 98 weight percent of a first fused silica having an average particle size of 1 micrometer to about 30 micrometers, and about 2 to about 25 weight percent of a second fused silica having an average particle size of about 0.03 micrometer to less than 1 micrometer.
21. The curable composition of claim 1 , further comprising a cure accelerator selected from imidazole compounds, tertiary amines, phosphines, phosphine oxides, diphosphines, phosphonium salts, phenol complexes of the foregoing, and combinations thereof.
22. The curable composition of claim 21 , wherein the cure accelerator comprises triphenylphosphine.
23. The curable composition of claim 1 , further comprising a flame retardant selected from ammonium polyphosphate, melamine phosphate, melamine polyphosphate, melamine cyanurate, resorcinol bis(diphenyl phosphate), piperazine-N,N′-bis(di-(2,6-dimethylphenyl)phosphoramidate), and combinations thereof.
24. The curable composition of claim 1 , further comprising an additive selected from silane coupling agents, mold release agents, colorants, thermal stabilizers, adhesion promoters, ion scavengers, low stress additives, and combinations thereof.
25. The curable composition of claim 1 , exhibiting a copper adhesion at 23° C. of about 5.7 to about 6.3 megapascals, measured according to SEMI G69-0996.
26. A curable composition, comprising:
about 70 to about 98 parts by weight of an epoxy resin comprising a monomeric epoxy resin and an oligomeric epoxy resin;
an effective amount of a phenolic novolac hardener;
about 2 to about 30 parts by weight of a poly(arylene ether) resin having an intrinsic viscosity of about 0.05 to about 0.30 deciliters per gram and comprising less than 5 weight percent of particles greater than 100 micrometers; and
about 70 to about 95 weight percent of a fused silica filler, based on the total weight of the curable composition; wherein the fused silica filler comprises, based on the total weight of fused silica filler, about 75 to about 98 weight percent of a first fused silica having an average particle size of 1 micrometer to about 30 micrometers, and about 2 to about 25 weight percent of a second fused silica having an average particle size of about 0.03 micrometer to less than 1 micrometer;
wherein all parts by weight are based on 100 parts by weight total of the epoxy resin and the poly(arylene ether) resin.
27. A curable composition, comprising:
about 70 to about 98 parts by weight of an epoxy resin comprising a biphenyl epoxy resin and an epoxy cresol novolac resin;
about 10 to about 100 parts by weight of a phenolic novolac hardener;
about 0.2 to about 10 parts by weight of triphenylphosphine;
about 2 to about 30 parts by weight of a poly(arylene ether) resin having an intrinsic viscosity of about 0.05 to about 0.15 deciliters per gram measured at 25° C. in chloroform and comprising less than 1 weight percent of particles greater than 60 micrometers; and
about 70 to about 95 weight percent of a fused silica filler, based on the total weight of the curable composition; wherein the fused silica filler comprises, based on the total weight of fused silica filler, about 75 to about 98 weight percent of a first fused silica having an average particle size of 1 micrometer to about 30 micrometers, and about 2 to about 25 weight percent of a second fused silica having an average particle size of about 0.03 micrometer to less than 1 micrometer;
wherein all parts by weight are based on 100 parts by weight total of the epoxy resin and the poly(arylene ether) resin.
28. A method of encapsulating a solid state device, comprising:
encapsulating a solid state device with a curable composition comprising
an epoxy resin,
a hardener,
a poly(arylene ether) resin comprising less than 5 weight percent of particles greater than 100 micrometers, and
about 70 to about 95 weight percent of a silica filler, based on the total weight of the curable composition, and
curing the curable composition.
29. An encapsulated solid state device, comprising:
a solid state device; and
a cured composition encapsulating the solid state device; wherein the cured composition comprises the products obtained on curing a curable composition comprising
an epoxy resin,
a hardener,
a poly(arylene ether) resin comprising less than 5 weight percent of particles greater than 100 micrometers, and
about 70 to about 95 weight percent of a silica filler, based on the total weight of the curable composition.