Underfill material including block copolymer to tune coefficient of thermal expansion and tensile modulus

Abstract

Embodiments of the present disclosure are directed toward underfill material including block copolymer. In one embodiment, an underfill material includes epoxy material and a copolymer including an epoxy-philic block and an epoxy-phobic block, wherein the epoxy-philic block is miscible in the epoxy material, the epoxy-phobic block is covalently bonded with the epoxy-philic block, the epoxy-phobic block is separated in a microphase domain within the epoxy material and the epoxy-philic block is configured to restrict thermal expansion or contraction of the epoxy material.

1 - 7 . (canceled) 
     
     
         8 . An integrated circuit (IC) assembly comprising:
 a package substrate;   a die coupled with the package substrate; and   an underfill material disposed between the die and the package substrate, the underfill material including:
 epoxy material, and 
 a copolymer including an epoxy-philic block and an epoxy-phobic block, wherein the epoxy-philic block is miscible in the epoxy material, the epoxy-phobic block is covalently bonded with the epoxy-philic block, the epoxy-phobic block is separated in a microphase domain within the epoxy material and the epoxy-philic block is configured to restrict thermal expansion or contraction of the epoxy material. 
   
     
     
         9 . The IC assembly of  claim 8 , wherein the package substrate is an epoxy-based laminate package substrate. 
     
     
         10 . The IC assembly of  claim 8 , wherein:
 the die is coupled with the substrate using one or more die-level interconnect structures; and   the underfill material is in direct contact with the one or more die-level interconnect structures.   
     
     
         11 . The IC assembly of  claim 8 , wherein the underfill material encapsulates the die. 
     
     
         12 . The IC assembly of  claim 8 , wherein the epoxy-phobic block includes a material selected from the group consisting of poly(ethylene-alt-propylene) (PEP), poly(nbutyl-acrylate) (PnBA), poly(styrene) (PS), polybutadiene (PBD), polypropylene oxide (PPO), polyethylene (PE), polyisoprene (PI), poly(butyleneoxide) (PBO), poly(hexylmethacrylate) (PHMA), and styrene-ethylene/butylene-styrene (SEBS). 
     
     
         13 . The IC assembly of  claim 8 , wherein the epoxy-philic block includes a material selected from the group consisting of poly(ethylene oxide) (PEO), poly(methyl methacrylate) (PMMA), poly(glycidyl methacrylate) (PGMA), poly (2-vinyl pyridine) (P2VP), poly(caprolactone) (PCL), and polyacrylic acid (PAA). 
     
     
         14 . The IC assembly of  claim 8 , wherein the copolymer is configured to reduce a tensile modulus of the underfill material. 
     
     
         15 . A method comprising:
 providing an underfill material comprising:
 epoxy material, and 
 a copolymer including an epoxy-philic block and an epoxy-phobic block, wherein the epoxy-philic block is miscible in the epoxy material and the epoxy-phobic block is covalently bonded with the epoxy-philic block; 
   depositing the underfill material between a package substrate and a die coupled with the package substrate; and   curing the underfill material, wherein the epoxy-phobic block is separated in a microphase domain within the epoxy material and the epoxy-philic block is configured to restrict thermal expansion or contraction of the epoxy material.   
     
     
         16 . The method of  claim 15 , wherein depositing the underfill material further comprises depositing the underfill material to substantially encapsulate the die. 
     
     
         17 . The method of  claim 15 , wherein providing the underfill material comprises:
 providing the epoxy-phobic block of the copolymer, the epoxy-phobic block including a material selected from the group consisting of poly(ethylene-alt-propylene) (PEP), poly(nbutyl-acrylate) (PnBA), poly(styrene) (PS), polybutadiene (PBD), polypropylene oxide (PPO), polyethylene (PE), polyisoprene (PI), poly(butyleneoxide) (PBO), poly(hexylmethacrylate) (PHMA), and styrene-ethylene/butylene-styrene (SEBS); and   providing the epoxy-philic block of the copolymer, the epoxy-philic block including a material selected from the group consisting of poly(ethylene oxide) (PEO), poly(methyl methacrylate) (PMMA), poly(glycidyl methacrylate) (PGMA), poly (2-vinyl pyridine) (P2VP), poly(caprolactone) (PCL), and polyacrylic acid (PAA).   
     
     
         18 . The method of  claim 17 , wherein providing the underfill material comprises providing the copolymer, the copolymer including a material selected from the group consisting of PEO-PEP, PEO-PEP-PEO, PEO-PS, PMMA-PS, P2VP-PS, PGMA-PHMA, and PS-PCL. 
     
     
         19 . The method of  claim 15 , further comprising:
 coupling the die with the package substrate.   
     
     
         20 . The method of  claim 19 , wherein:
 coupling the die with the package substrate is performed using one or more die-level interconnect structures; and   the underfill material is in direct contact with the one or more die-level interconnect structures subsequent to depositing the underfill material.