| 摘要 |
New heat spreaders are proposed to connect high power, high heat generating electronic devices to their downstream heat dissipating cooling components. First, the spreaders distribute the high heat flux over a wider surface area, thus reducing the flux to levels more easily handled by the downstream cooling system. Second, the spreaders incorporate flexible columns or elements to join the electronic devices to the main body of the spreader, so as to negate the undesirable effects of CTE mismatch. Columns with a higher standoff distance between the components are more flexible than a direct flat interface attachment between the heat source and the heat sink, and will have less chance of delaminating. Several embodiments are proposed and can be used in appropriate situations. The heat spreaders can be helpful in harsh environments and in high heat generating applications, such as spacecraft, satellites, as well as land locked high power computer systems. |
| 主权项 |
1. A multi-level heat spreader, for transferring heat from a primary heat source, generating a certain amount of heat, exiting from a primary heat source heat exit area, with a certain heat source heat flux, to a final heat dissipating device, wherein
a) said heat source heat flux is larger that the heat flux that can be tolerated by said final heat dissipating device, b) said multi-level heat spreader comprising: c) a first level heat spreader unit and second level heat spreader unit, wherein d) said first level heat spreader unit comprises a number of first heat conducting elongated elements and a first heat conducting platform; e) said second level heat spreader unit comprising a number of second heat conducting elongated elements and a second heat conducting platform; f) each one of said first heat conducting elongated elements having a foot, attached to and thermally engaging said primary heat source at the primary heat source heat exit area, and a head, at the opposite end of the elongated element, attached to and thermally engaging said first heat conducting platform; g) each one of said second heat conducting elongated elements having a foot attached to and thermally engaging said first heat conducting platform, and a head, at the opposite end of the elongated element, attached to and thermally engaging said second heat conducting platform; wherein h) the heat is transmitted from the primary heat source heat exit area through the first heat conducting elongated elements of the first level heat spreader unit to the first heat conducting platform, and subsequently the heat is transferred from said first heat conducting platform through the second heat conducting elongated elements of said second level heat spreader unit to the second level heat conducting platform, thus i) said first heat conducting platform is acting as the heat source for the second level heat spreader unit, and wherein j) a heat exit surface area of said first heat conducting platform is larger than the surface area of the primary heat source heat exit area, resulting in that the heat flux at the surface of the first heat conducting platform is smaller than the heat flux at the primary heat source heat exit area, and wherein k) a heat exit surface area of said second heat conducting platform is larger yet than the surface area of the first heat conducting platform, resulting in that the heat flux at the surface of the second heat conduction platform is smaller yet than the heat flux at the surface area of the first heat conducting platform, thus l) said multi-level heat spreader providing a greater reduction of the heat flux at the surface area of the second heat conducting platform compared to the heat flux at the primary heat source heat exit area, wherein m) said heat flux at the surface area of the second heat conducting platform is considerably smaller than the heat flux at the primary heat source heat exit area, and is better adapted to engage said final heat dissipating device, compared to the heat flux at the primary heat source heat exit area. |
