Nanoparticle dispersions with low aggregation levels
View Patent ↗An apparatus comprising a substrate having a surface and a dielectric layer comprising a distribution of particles. The layer is located over the surface and has a dielectric constant of seven or more. Each particle has a particle core and a polymer shell that is chemically bonded thereto and located around the associated particle core. Each particle core includes a material having a dielectric constant of about fifteen or more. Aggregates of the particle cores having diameters of about 0.5 microns or more are substantially absent from the layer.
1. An apparatus, comprising:
a substrate having a surface; and
a dielectric layer comprising a polymer medium and a distribution of particle cores within the medium, the dielectric layer being located over said surface and having a dielectric constant of seven or more,
wherein each one of the particle cores comprises TiO 2 and has a polymer shell comprising a polymer chain chemically bonded thereto via a phosphonate moiety
wherein said polymer medium is formed from the polymer shells, and said polymer chain is selected from the group consisting of
styrene;
vinyl pyridine;
methyl methacrylate; and
butyl methacrylate.
2. The apparatus as recited in claim 1 , wherein aggregates of said particle cores, the aggregates having diameters of about 0.5 μm or more, are substantially absent from said distribution of particle cores.
3. The apparatus as recited in claim 1 , wherein said dielectric layer is a gate dielectric of a FET.
4. The apparatus of claim 1 , wherein said polymer chain is bonded to said phosphonate moiety via a linear methylene chain having between 6 and 20 carbon atoms.
5. The apparatus of claim 1 , wherein said polymer chain is further bonded to said particle core via a linear methylene chain having between 6 and 20 carbon atoms.
6. An apparatus, comprising:
a substrate having a surface; and
a dielectric layer comprising a polymer medium and a distribution of particle cores within the polymer medium, the dielectric layer being located over said surface and having a dielectric constant of seven or more,
wherein each one of the particle cores has a polymer shell chemically bonded thereto and located around the one of the particle cores, each particle core comprising a material having a dielectric constant of about fifteen or more, and
wherein said polymer medium is formed from the polymer shells and the polymer shells comprise a linear methylene chain having between 6 and 20 carbon atoms and a polymer chain connected to the methylene chain.
7. The apparatus as recited in claim 6 , wherein said particle cores comprise a material having a dielectric constant of about thirty or more.
8. The apparatus as recited in claim 6 , wherein said particle cores comprise titania or a perovskite.
9. The apparatus of claim 6 , wherein the polymer chain and an aryl moiety are bonded to a same carbon atom of said methylene chain.
10. The apparatus of claim 6 , wherein said polymer chain is formed from a monomer selected from the group consisting of:
styrene;
vinyl pyridine;
methyl methacrylate; and
butyl methacrylate.
11. The apparatus of claim 6 , wherein said polymer shell is bonded to the associated particle core by a phosphonate moiety.
12. The apparatus of claim 5 , wherein said methylene chain is bonded to said particle core by said phosphonate moiety.
13. The apparatus of claim 5 , wherein said poly(methyl methacrylate) chain and an aryl moiety are bonded to a same carbon atom of said methylene chain.
14. The apparatus as recited in claim 6 , wherein said particle cores comprise titania or a perovskite.
15. The apparatus as recited in claim 6 , wherein said dielectric layer is a gate dielectric of a FET.
16. The apparatus of claim 5 , wherein the polymer chain and an aryl moiety are bonded to a same carbon atom of said methylene chain.