Heat transfer apparatus and method of manufacturing an integrated circuit and heat sink assembly
View Patent ↗A method for cooling integrated circuit assemblies uses a heat sink having a base and a displacement element having a size substantially similar to an area of heat concentration appropriately positioned on the integrated circuit. A compressive force placed upon the displacement element between the heat sink and the integrated circuit provides an optimum thermal resistance at an interface between the IC and the heat sink for efficient transfer of heat to the heat sink.
1. A method for mounting a heat sink to a heat source comprising the steps of:
providing a heat source and a heat sink, said heat source having an area of heat concentration,
determining an optimum size for a thermal interface material as a function of said area of heat concentration,
placing said optimally sized thermal interface material between said heat source and said heat sink, and
applying compression to said optimally sized thermal interface material between said heat source and said heat sink said step of determining further comprising the steps of establishing values that represent fixed characteristics for behavior of said thermal interface material in response to compression, establishing constraining equations for an initial size of said thermal interface material, a thickness of said thermal interface material as a function of said compression, and a thermal resistance of said thermal interface material, wherein said step of determining said optimum size for said thermal interface material comprises minimizing said thermal resistance of said thermal interface material.
2. A method for mounting a heat sink to a heat source as recited in claim 1 , said step of determining an optimum size further comprising providing an eta factor for defining a characteristic for a non-uniform heat source.
3. A method for mounting a heat sink to a heat source as recited in claim 2 wherein said eta factor defines a subset of a surface area of said heat source that represents an area of heat concentration.
4. A method of manufacturing an integrated circuit assembly comprising the steps of:
providing a heat sink having a base,
determining a size and position of an area of heat concentration on said integrated circuit,
determining an optimum size for a thermal interface material as a function of said area of heat concentration,
placing said optimally sized thermal interface material between said integrated circuit and said base, and
applying compression to said optimally sized thermal interface material between said integrated circuit and said base said step of determining an optimum size further comprising the steps of establishing values that represent fixed characteristics for behavior of said thermal interface material in response to compression, establishing constraining equations for an initial size of said thermal interface material, a thickness of said thermal interface material as a function of said compression, and a thermal resistance of said thermal interface material, wherein said step of determining said optimum size for said thermal interface material comprises minimizing said thermal resistance of said thermal interface material.
5. A method of manufacturing an integrated circuit as recited in claim 4 wherein said integrated circuit is a microprocessor encased in a lid.
6. A method of manufacturing a printed circuit board assembly comprising the steps of:
providing an integrated circuit mounted to a printed circuit board, said integrated circuit requiring cooling during operation and having an area of heat concentration,
providing a heat sink for said integrated circuit,
determining an optimum size for a thermal interface material as a function of said area of heat concentration,
placing said optimally sized thermal interface material between said integrated circuit and said heat sink, and
applying compression to said optimally sized thermal interface material between said integrated circuit and said heat sink said step of determining an optimum size further comprising the steps of establishing values that represent fixed characteristics for behavior of said thermal interface material in response to compression, establishing constraining equations for an initial size of said thermal interface material, a thickness of said thermal interface material as a function of said compression, and a thermal resistance of said thermal interface material, wherein said step of determining said optimum size for said thermal interface material comprises minimizing said thermal resistance of said thermal interface material.
7. A method of manufacturing a printed circuit board assembly as recited in claim 6 wherein said integrated circuit comprises a microprocessor encased in a lid.
8. A method of manufacturing an integrated circuit assembly as recited in claim 6 , said step of determining an optimum size further comprising providing an eta factor for defining a characteristic for a non-uniform heat source.
9. A method of manufacturing an integrated circuit assembly as recited in claim 8 wherein said eta factor defines a subset of a surface area of said heat source that represents an area of heat concentration.