The present invention is generally directed to an electronic assembly and, more specifically, to an electronic assembly with integral thermal transient suppression.
In general, higher power integrated circuit (IC) components require heat removal from the components to prevent early failure of the components. In various applications, high-power components may have relatively short, e.g., a few seconds, high-power thermal transient events. In general, the amount of thermal energy dissipated in these high-power thermal transient events needs to be dissipated rapidly and expediently.
In various electronic assemblies, a high-power thermal transient event may repeatedly occur and, if the energy is not continuously dissipated, heat may build up in the electronic components of the assemblies, causing failure of the components. In general, assembly designers have addressed short-term high-power thermal transients by implementing high-performance steady-state thermal structures to absorb the short-term high-power thermal transients. Unfortunately, high-performance steady-state thermal structures, such as heat sinks, fans, etc., tend to be relatively expensive to implement. When implemented, heat sinks have typically been provided on a top side of an electronic component. Alternatively, some electronic assemblies have utilized relatively expensive via structures implemented in a substrate underneath an electronic component, e.g., an integrated circuit (IC) chip.
What is needed is a technique for providing thermal transient suppression for an electronic assembly that is relatively inexpensive and efficient.
The present invention is directed to an electronic assembly that includes integral thermal transient suppression. In one embodiment, an electronic assembly includes an integrated circuit (IC) device package that includes a cavity. In this embodiment, an IC chip is disposed within the cavity and a transient thermal suppression material (TTSM) is disposed in the cavity in thermal contact with the IC chip. According to another embodiment of the present invention, a heat sink is also provided in thermal contact with the chip. In this embodiment, the heat sink serves as a cover of the packaged IC chip. According to another embodiment, the heat sink includes fins extending from an upper surface of the heat sink. In still another embodiment, the heat sink includes fins extending from a lower surface of the heat sink with the fins being in thermal contact with the TTSM. In general, the TTSM may be thought of as a phase change material that absorbs energy dissipated by the IC chip in a phase change event.
According to another embodiment of the present invention, an electronic assembly with integral thermal suppression includes an integrated circuit (IC) chip and a thermal transient suppression material (TTSM) that is disposed in grooves that are formed in a non-active side of a body of the IC chip. According to this aspect of the present invention, a dam is located at opposite ends of the grooves to retain the TTSM. The dam may be made of an epoxy or may be integral to the body of the IC chip. According to still another aspect of the present invention, the assembly includes a substrate that has a plurality of conductive traces, which are coupled to the IC chip on an active side of the IC chip.
These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims and appended drawings.
The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
According to one embodiment of the present invention, a technique for removing heat from a modified device package is disclosed. As is discussed above, high-power electronic components require heat removal to prevent failure. As is also discussed above, many devices experience relatively short high-power thermal transient events. According to one aspect of the present invention, a phase change thermal transient suppression material (TTSM) is implemented within a dual in-line package (DIP) cavity, to absorb transient thermal energy. In certain situations, it may also be desirable to implement a heat sink that is placed in contact with a thermal transient suppression material (TTSM) to improve steady-state thermal performance.
In general, an electronic assembly configured according to this embodiment of the present invention provides a reduced cost product, as contrasted with assemblies that implement conventional cooling concepts, that allows for the utilization of a device package cover that may be made of a variety of materials, such as metals with large heat capacity, e.g., copper. According to one aspect of the present invention, heat is removed from a top side of a die, located in a cavity package, to air through a modified package cover.
With reference to
The assembly 100 may also include a heat sink 112 having lower fins 112B and/or upper fins 112A. As is shown, the fins 112B are in contact with the TTSM 110 and the heat sink 112 serves as a cover for the packaged IC chip 106. The clearance between the TTSM 110 and the cover may be about ten to fifteen mils. The TTSM 110 may be a variety of materials, such as those disclosed in U.S. Pat. No. 6,703,128, entitled “THERMALLY-CAPACITIVE PHASE CHANGE ENCAPSULANT FOR ELECTRONIC DEVICES,” to Bruce A. Myers et al., which is hereby incorporated herein by reference in its entirety.
With reference to
As is apparent from the graph 200, electronic assemblies that include a TTSM within a device cavity have substantially decreased temperature transients. The curves of
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From the curves of
Accordingly, electronic assemblies have been described herein, which include integral thermal transient suppression, which advantageously allow an electronic assembly to be produced more economically. Such an electronic assembly is particularly advantageous when implemented within the automotive environment, which increasingly utilize high-power devices that frequently experience thermal transients.
The above description is considered that of the preferred embodiments only. Modifications of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the doctrine of equivalents.