# US 7,742,297 B2 · Ceramic foam electronic component cooling > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,742,297 B2 - Document ID: US7742297B2 - Status: Granted - Kind: B2 - Application number: 11/407,433 - Filed: 2006-04-20 - Published: 2007-10-25 - Granted: 2010-06-22 - Earliest claimed: 2006-04-20 - Assignees: The Boeing Company - Inventors: William W. Behrens; Andrew R. Tucker - Web page: https://patentgrep.com/patent/US7742297B2 ## CPC - H10W 40/43: by flowing gases, e.g. forced air cooling - F28F 13/003: {by using permeable mass, perforated or porous materials (F28F13/18 takes precedence)} - H10W 40/257: {having a heterogeneous or anisotropic structure, e.g. powder or fibres in a matrix, wire mesh or porous structures (H10W40/254, H10W40/251 take precedence)} - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 - F28F: DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION (water and air traps, air venting F16) ## Abstract In an exemplary apparatus for cooling an electronic component, a housing defines an inlet port and an exhaust port and a foam member is disposed within the housing. The foam member has a shape that conforms to a shape of at least one surface of an electronic component such that the foam member is receivable thereon in thermal communication. The foam member has a pore size of no more than around 50 micrometers and a porosity of at least around 80 percent. The foam member is arranged within the housing such that coolant is flowable through the foam member. Pore size may be around 35 micrometers and porosity may be around 90 percent. Foam may be a ceramic foam that includes silica, aluminum oxide, and aluminum borosilicate fibers. In an application, at least one exemplary apparatus may be received in thermal communication on an upper case of an electronic chip. ## Claims ### Claim 1 An apparatus for cooling an electronic component, the apparatus comprising: a foam member having a shape that conforms to a shape of at least a top surface of an electronic component such that the foam member is receivable thereon in thermal communication with at least the top surface of the electronic component, the foam member having a pore size of less than 50 micrometers and a porosity of at least around 80 percent, the foam member being arranged such that coolant is flowable through the foam member; and a housing partially covering the foam member, wherein the housing includes: an inlet port, approximately above a center of the top surface of the electronic component, wherein at least one side of the foam member is not covered by the housing, and wherein the coolant received at the inlet port exits the foam member through the at least one side of the foam member that is not covered by the housing. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the pore size is about 35 micrometers. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the porosity is about ninety percent. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the foam member includes ceramic foam. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the ceramic foam includes silica; aluminum oxide; and aluminum borosilicate fibers. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the housing is made from an impermeable sealant, and wherein the impermeable sealant further adheres the foam member to the top surface of the electronic component. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the at least one side of the foam member that is not covered by the housing is below the top surface of the electronic component so that the coolant received at the inlet port flows through the foam member over the top surface and over at least a portion of sides of the electronic component before exiting via the at least one side of the foam member that is not covered by the housing. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the foam member extends past a plurality of edges of the top surface of the electronic component, and wherein the at least one side of the foam member that is not covered by the housing includes each side of the foam member past the edges of the top surface. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein the at least one side of the foam member that is not covered by the housing includes a side of the foam member that is parallel to the top surface of the electronic component and that is below the top surface of the electronic component from the inlet port. ### Claim 10 A method of cooling an electronic component, the method comprising: flowing coolant into a housing at least partially covering a foam member at an entrance adjacent to a center of a top surface of an electronic component, wherein the foam member substantially uniformly distributes the coolant from the entrance through the foam member, and wherein the foam member has a pore size less than about 50 micrometers and a porosity of at least about 80 percent; and discharging the coolant from the housing and the foam member at one or more sides of the foam member that are not covered by the housing and that are beyond at least one side of the electronic component. ### Claim 11 (depends on 10) The method of claim 10, wherein the electronic component includes a chip having a case with a top and sides, and wherein the foam member is received in thermal communication on at least one of the top and the sides of the case. ### Claim 12 (depends on 10) The method of claim 10, wherein the coolant includes cooling air. ### Claim 13 A circuit board assembly comprising: a circuit board having at least one electronic component mounted on a side of the circuit board; and an apparatus for cooling the electronic component, the apparatus being attached in thermal communication to the electronic component, the apparatus including: a housing defining an inlet port adjacent to a center of a top surface of the electronic component; and a foam member partially covered by the housing, the foam member having a shape that conforms to a shape of the top surface of the electronic component, the foam member having a pore size of less than 50 micrometers and a porosity of at least around 80 percent, wherein coolant is flowable through the foam member along the top surface of the electronic component and exits the foam member and the housing through at least one side of the foam member that is not covered by the housing. ### Claim 14 (depends on 13) The circuit board assembly of claim 13, wherein an average pore size of the foam member is about 35 micrometers. ### Claim 15 (depends on 13) The circuit board assembly of claim 13, wherein the porosity is about ninety percent. ### Claim 16 (depends on 13) The circuit board assembly of claim 13, wherein the foam includes ceramic foam. ### Claim 17 (depends on 13) The circuit board assembly of claim 13, wherein the housing is made from an impermeable sealant. ### Claim 18 (depends on 17) The circuit board assembly of claim 17, wherein the impermeable sealant further bonds the foam member to the top surface of the electronic component. ### Claim 19 (depends on 13) The circuit board assembly of claim 13, wherein the electronic component includes a chip having a case including the top surface and a base removed from the top surface by a plurality of sides, and wherein the foam member is received in thermal communication with the top surface and at least one side of the plurality of sides of the case, and wherein the at least one side of the foam member that is not covered by the housing is adjacent to the at least one side of the plurality of sides of the case and open toward the base to allow the coolant to exit by flowing toward the base of the electronic component. ### Claim 20 (depends on 13) The circuit board assembly of claim 13, wherein the coolant includes cooling air. ### Claim 21 (depends on 13) The circuit board assembly of claim 13, wherein the coolant has a non-zero slip velocity at walls of pores of the foam member.