Package structure and method for fabricating the same

A method for fabricating a package structure, comprising:

• premixing a first one-dimensional (1D) nanomaterial and a first 2D material in a first solution, wherein the first 1D nanomaterial has a higher length-to-width ratio than the first 2D material, such that a first premixing weight ratio of a weight of the first 1D nanomaterial to a weight of the first 2D material is in a range from about 10% to about 90%;
• drying the first solution to form a first composite filler;
• melt-mixing a first prepolymeric material with the first composite filler to form a first composite material;
• encapsulating a die using the first composite material;
• attaching the die to a package substrate;
• premixing a second 1D nanomaterial and a second 2D material in a second solution, such that a second premixing weight ratio of a weight of the second 1D nanomaterial to a weight of the second 2D material is different than the first premixing weight ratio of the weight of the first 1D nanomaterial to the weight of the first 2D material;
• drying the second solution to form a second composite filler;
• melt-mixing a second prepolymeric material with the second composite filler to form a second composite material comprising the second prepolymeric material and the second composite filler;
• and
• dispensing the second composite material between the die and the package substrate.

A method for fabricating a package structure, comprising:

• premixing carbon nanotubes and a hexagonal boron nitride in a first solvent to form a first solution, wherein a weight of the carbon nanotubes to a weight of the hexagonal boron nitride define a first premixing weight ratio;
• removing the first solvent from the first solution to form a first composite filler;
• pulverizing the first composite filler;
• mixing a first prepolymeric material with the first pulverized composite filler to form a first composite material;
• encapsulating a die using the first composite material, the first composite material comprising the carbon nanotubes and the hexagonal boron nitride;
• attaching the die to a package substrate;
• premixing a 1D nanomaterial and graphene in a second solvent to form a second solution, wherein a weight of the 1D nanomaterial to a weight of the graphene define a second premixing weight ratio different than the first premixing weight ratio of the weight of the carbon nanotubes to the weight of the hexagonal boron nitride;
• removing the second solvent from the second solution to form a second composite filler;
• pulverizing the second composite filler;
• mixing a second prepolymeric material with the pulverized composite filler to form a second composite material;
• and
• depositing the second composite material comprising the 1D nanomaterial and the graphene over the package substrate and the die.