Thermal management of high heat flux multicomponent assembly
An electronic package includes a thermal interface for dissipating heat from an electronic component array including a plurality of electronic components secured to a substrate. The thermal interface includes a thin heat spreading layer for transferring heat input from the electronic components along directions transverse to heat flux. The heat spreading layer is part of a laminate structure that is efficiently utilized by spreading thermal energy across an input plane.
1. An electronic package, comprising:
a substrate;
an electronic component array including a plurality of discrete spaced-apart electronic components secured to said substrate;
a heat dissipater; and
a thermal interface positioned in a thermal pathway between said electronic component array and said heat dissipater, said thermal interface including a heat spreading layer and a compliant layer, and a thickness defined along a thickness axis through said heat spreading layer and said compliant layer, wherein said heat spreading layer is less than 20% of the thickness and exhibits a first thermal conductivity, and said compliant layer exhibits a second thermal conductivity that is substantially less than the first thermal conductivity and a compressive modulus of between 10 4 Pa-10 6 Pa.
2. The electronic package of claim 1 wherein said first thermal conductivity is at least 100 W/m*K, and said second thermal conductivity is between 1-15 W/m*K.
3. The electronic package of claim 2 wherein said thermal interface exhibits an electrical resistivity of at least 10 8 Ω*cm through the thickness along the thickness axis.
4. The electronic package of claim 1 wherein said thermal interface is secured to at least one of said heat dissipater and said electronic component array.
5. The electronic package of claim 4 , including an adhesion material for securing said heat spreading layer to a plurality of the electronic components of said electronic component array.
6. The electronic package of claim 5 wherein said adhesion material includes a pressure-sensitive adhesive.
7. The electronic package of claim 1 wherein said substrate is a circuit board.
8. The electronic package of claim 1 wherein said electronic components include one or more of an integrated circuit, a resistor, a transistor, a capacitor, an inductor, and a diode.
9. The electronic package of claim 1 wherein said heat spreading layer is selected from the group consisting of copper, aluminum, graphite, and boron nitride.
10. The electronic package of claim 1 wherein said heat spreading layer is between 25-125 μm along the thickness axis.
11. The electronic package of claim 1 wherein said compliant layer includes particulate filler dispersed in a silicone polymer matrix.
12. The electronic package of claim 1 wherein the thickness axis is parallel to said thermal pathway.
13. A method for preparing an electronic package, said method comprising:
a. providing a thermal interface having a heat spreading layer and a compliant layer, and a thickness defined along a thickness axis through said heat spreading layer and said compliant layer, wherein said thermal interface exhibits an initial thermal conductivity, and wherein said heat spreading layer is less than 20% of the thickness and exhibits a thermal conductivity of at least 100 W/m*K, and said compliant layer exhibits a compressive modulus of between 10 4 Pa-10 6 Pa;
b. affixing said thermal interface in a thermal pathway between a heat dissipater and an electronic component array of a plurality of electronic components secured to a substrate; and
c. compressing said thermal interface along the thickness axis to reduce said thickness, wherein the thermal interface, having a thickness reduction of up to 50%, exhibits a compressed thermal conductivity that is at least 80% of the initial thermal conductivity.
14. The method of claim 13 wherein said compliant layer of said thermal interface exhibits a thermal conductivity of between 1-15 W/m*K.
15. The method of claim 13 wherein said thickness axis is parallel to the thermal pathway.
16. The method of claim 13 wherein said thermal interface exhibits an electrical resistivity of at least 10 8 Ω*cm through the thickness along the thickness axis.
17. The method of claim 13 wherein compressing includes moving at least one of said substrate and said heat dissipater toward the other of said substrate and said heat dissipater.
18. An electronic package, comprising:
a substrate;
an electronic component array including a plurality of discrete spaced-apart electronic components secured to said substrate;
a thermal interface including a heat spreading layer and a compliant layer, and a thickness defined along a thickness axis through said heat spreading layer and said compliant layer, wherein said heat spreading layer is less than 20% of the thickness and exhibits a first thermal conductivity, and said complaint layer exhibits a second thermal conductivity that is substantially less than the first thermal conductivity and a compressive modulus of between 10 4 Pa-10 6 Pa, wherein said heat spreading layer is thermally connected to said electronic component array; and
a heat dissipater being thermally connected to said compliant layer of said thermal interface.
19. The electronic package of claim 18 wherein said first thermal conductivity is at least 100 W/m*k, and said second thermal conductivity is between 1-15 W/m*K.
20. The electronic package of claim 19 wherein said thermal interface exhibits an electrical resistivity of at least 10 8 Ω*cm through the thickness along the thickness axis.