The present invention is generally directed to an electronic module and, more specifically, to an electronic module that includes a conductive polymer that facilitates improved thermal dissipation and may provide backside electrical contact.
Electronic modules have been widely utilized in the automotive industry and have taken various forms, such as an all silicon ignition (ASI) module implemented in a TO247 package. Typically, such electronic modules have been encapsulated, e.g., with an epoxy mold compound, to seal the electronic components of the module from the environment. In a typical prior art electronic module, an electronic component, e.g., an integrated circuit (IC) die, has been electrically coupled to conductive traces formed on a surface of a substrate through a solder reflow process. In certain applications, backside electrical contact has been made between the die and the substrate through the use of wire bond interconnections. In other prior art electronic modules, backside electrical contact has been achieved with a conductive metal cap. While many electronic module designs generally function adequately in low power applications, these designs may experience problems adequately dissipating heat in higher power applications.
What is needed is a technique that provides an electronic module with improved thermal dissipation. It would also be desirable if the technique readily facilitated backside electrical contact of integrated circuit (IC) dies associated with the electronic module.
The present invention is directed to an electronic module that includes a substrate, at least one surface mounted integrated circuit (IC) component and a conductive polymer. The substrate includes a plurality of electrically conductive traces formed on at least a first surface of the substrate. The at least one surface mountable integrated circuit (IC) component includes a plurality of conductive pads, formed on at least a first surface of the component, that are electrically coupled to at least one of the conductive traces. The conductive polymer is in contact with at least a portion of a second surface, which is opposite the first surface, of the component and the substrate.
According to another aspect of the present invention, the electronic module includes an electrically non-conductive overmold material that encapsulates the component, the conductive polymer and at least a portion of the substrate. According to one embodiment, the overmold material is an epoxy molding compound. According to other aspects of the present invention, the conductive polymer may be a thermally conductive polymer and/or an electrically conductive polymer. When the conductive polymer is an electrically conductive polymer, the polymer may be a silver paste that may be readily printed over the component. It should be appreciated that the present invention is applicable to a wide variety of substrates, such as ceramic substrates and printed circuit boards (PCBs) and a wide variety of components, such as flip chips.
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:
While some electronic module designs have addressed heat dissipation, while simultaneously providing backside electrical connection for integrated circuit (IC) dies associated with the module, such designs have generally not maximized heat dissipation of the module in a relatively economical manner. According to various embodiments of the present invention, a conductive polymer is utilized to enhance thermal dissipation of an electronic module. According to other aspects of the present invention a conductive polymer may also be selected to provide thermal dissipation and backside electrical contact.
With reference to
With reference to
As is well known to those of ordinary skill in the art, underfilling an electrical component prior to overmolding prevents damage to electrical connections that join the component to a substrate. Next, in step 312, the underfill is cured. Then, in step 314, a conductive paste, i.e., the conductive polymer 122, is printed onto a portion of the substrate 108 and a portion of the IC 110. As previously mentioned, the conductive polymer 122 may increase heat transfer from the IC 110 and may also provide backside electrical connection between the IC 110 and the substrate 108. Next, in step 316, the polymer 122 is cured. Following the paste process, the module 100 is then ready for encapsulation.
As is shown in
With reference again to
Accordingly, an electronic module has been described herein that exhibits increased thermal performance through the use of conductive polymer. The conductive polymer can also be utilized to provide backside electrical contact when desired.
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.