This application claims the benefit under 35 U.S.C. § 119(a) of European Application No. 22193335.1 filed Aug. 31, 2022, the contents of which are incorporated by reference herein in their entirety.
Aspects of the present disclosure generally relate to an electronic package and a method for manufacturing such electronic packages. The method is particularly suitable for manufacturing a plurality of electronic packages substantially simultaneously using a single molding cavity.
Electronic packages typically comprise a semiconductor die on which a circuit is integrated, which semiconductor die is encapsulated by a package material, such as solidified molding compound, to protect said semiconductor die.
A known method of manufacturing an electronic package is illustrated using a simplified cross-sectional view in
Semiconductor die 3 includes a first electrical contact facing die pad 2, and a second electrical contact opposite the first electrical contact. Each package portion in this example further includes a clip lead 4 which is fixedly attached and electrically connected to the second electrical contact. Clip lead 4 may form a package terminal of the eventual electronic package, or may be fixedly and electrically connected to a package contact 5, for example also included in frame 10, which package contact 5 may form a package terminal of the eventual electronic package. Furthermore, in this example, die pad 2 may be conductive and may itself form a package terminal of the eventual package. In that sense, the eventual electronic package will be mountable to an external surface, such as a printed circuit board (PCB), with die pad 2 and package contact 5 facing the external surface.
A mold is provided to arrange the package material encapsulating semiconductor dies 3. For example, frame 10 is arranged on a first mold portion 6a, and a second mold portion 6b is provided contacting frame 10 to form a molding cavity 7 enclosing and surrounding the plurality of package portions. An injection molding step can then be applied to inject the package material (e.g., a molding compound) into molding cavity 7. The mold is arranged until the package material is arranged, for example until the molding compound is solidified, after which the mold can be removed.
While arranging the package material, part of the package material may leak or flow into areas such as at position P indicated in
US2020/0176412A1 discloses a package and method of making a package. The package includes an electronic chip having at least one pad, an encapsulant at least partially encapsulating the electronic chip, and an electrically conductive contact element extending from the at least one pad and through the encapsulant so as to be exposed with respect to the encapsulant. The electrically conductive contact element comprises a first contact structure made of a first electrically conductive material on the at least one pad and comprises a second contact structure made of a second electrically conductive material and being exposed with respect to the encapsulant. At least one of the at least one pad has at least a surface portion which comprises or is made of the first electrically conductive material.
US2022/0115301A1 discloses an electronic device comprising a first substrate comprising a base, an electronic component over the first substrate and comprising a top side and a bottom side, a first terminal and a second terminal on the top side, and a third terminal on the bottom side, wherein the third terminal is coupled with the first substrate. The electronic device further comprises a second substrate over the electronic component, and an encapsulant over the first substrate, contacting a lateral side of the electronic component and contacting the second substrate. A first lead is coupled with and extends over the base of the first substrate, a second lead of the second substrate is coupled to the first terminal of the electronic component, and the first lead and the second lead are exposed from a top side of the encapsulant.
Aspects of the present disclosure relate to an electronic package and manufacturing method therefor in which the abovementioned drawback(s) do not occur, or hardly so.
A summary of aspects of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects and/or a combination of aspects that may not be set forth.
According to an aspect of the present disclosure, as defined in appended claims 1-8, a method for manufacturing an electronic package is provided. According to another aspect of the present disclosure, an electronic package as defined in appended claim 9 is provided.
By providing a first conductive mechanical support in the form of a clip lead in accordance with the above, the second mold portion can have a contact point to mechanically press down the frame and thereby prevent thick flashes of molding compound from forming under the frame, in particular under the die pads.
Next, the present disclosure will be described in more detail with reference to the appended drawings, wherein:
The present disclosure is described in conjunction with the appended figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.
In the appended figures, similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.
Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise,” “comprising,” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to.” As used herein, the terms “connected,” “coupled,” or any variant thereof means any connection or coupling, either direct or indirect, between two or more elements; the coupling or connection between the elements can be physical, logical, electromagnetic, or a combination thereof. Additionally, the words “herein,” “above,” “below,” and words of similar import, when used in this application, refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the detailed description using the singular or plural number may also include the plural or singular number respectively. The word “or,” in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.
The teachings of the technology provided herein can be applied to other systems, not necessarily the system described below. The elements and acts of the various examples described below can be combined to provide further implementations of the technology. Some alternative implementations of the technology may include not only additional elements to those implementations noted below, but also may include fewer elements.
These and other changes can be made to the technology in light of the following detailed description. While the description describes certain examples of the technology, and describes the best mode contemplated, no matter how detailed the description appears, the technology can be practiced in many ways. Details of the system may vary considerably in its specific implementation, while still being encompassed by the technology disclosed herein. As noted above, particular terminology used when describing certain features or aspects of the technology should not be taken to imply that the terminology is being redefined herein to be restricted to any specific characteristics, features, or aspects of the technology with which that terminology is associated. In general, the terms used in the following claims should not be construed to limit the technology to the specific examples disclosed in the specification, unless the detailed description section explicitly defines such terms. Accordingly, the actual scope of the technology encompasses not only the disclosed examples, but also all equivalent ways of practicing or implementing the technology under the claims.
To reduce the number of claims, certain aspects of the technology are presented below in certain claim forms, but the applicant contemplates the various aspects of the technology in any number of claim forms.
In
On each die pad 2, a semiconductor die 3 is provided. Semiconductor die 3 includes a first electrical contact (not shown) facing die pad 2, and a second electrical contact (not shown) opposite the first electrical contact. Here, it will be appreciated by the skilled person that the first electrical contact and the second electrical contact may each be formed in at least one metal layer of respective metal layer stacks comprising one or more such metal layers. Said metal layer stacks may be arranged on semiconductor die 3, in this case on opposite sides, and may provide electrical access to respective terminals of semiconductor die 3.
Two package portions are shown in
A mold is provided to arrange the package material encapsulating semiconductor dies 3. For example, the frame including die pads 2 is arranged on a first mold portion 6a, and a second mold portion 6b is provided contacting the frame to form a molding cavity 7 enclosing and surrounding the plurality of package portions. In
In the method according to an embodiment of the present disclosure, a first conductive mechanical support 8 is provided. In this example, first conductive mechanical support may be a clip lead comprising a first portion 8a fixedly attached and electrically connected to the second electrical contact of a first package portion, and a support portion 8b extending closer to second mold portion 8b than a remainder of the package portions. During the step of applying the molding compound and allowing it to solidify, second mold portion 6b is brought into contact with support portion(s) 8b at position(s) F and can exert a force thereon. In doing so, the package portion(s) corresponding to first conductive mechanical support(s) 8 is pressed down against first mold portion 6a, thereby preventing or limiting a flash of molding compound forming below said package portion.
Optionally, first conductive mechanical support 8 may further include a second portion 8c which is integrally connected to support portion 8b, and is fixedly attached and electrically connected to die pad 2 of an adjacent package portion. This provides further support and down-force during molding, and enables first conductive mechanical support 8 to form a package terminal for two respective package portions, as will be discussed further below with reference to
Die pads 2 may be stamped die pads as roughly shown in
In
In
In some embodiments, for example when semiconductor die 3 includes more than two terminals, the polishing operation may additionally expose further terminals of semiconductor die 3. For example, semiconductor die 3 may have a transistor integrated thereon having three terminals. The first electrical contact may be provided for a first terminal thereof, such as the drain. The second electrical contact may be provided for a second terminal thereof, such as a gate or source. Semiconductor die 3 may then further comprise a third electrical contact for a third terminal thereof, such as a source or gate, respectively, which may be arranged at a same side of semiconductor die 3 as the second electrical contact. In that case, the removal of part of the body, e.g., the grinding or polishing operation, may additionally expose the third electrical contact. This concept can be further extended to devices or circuits having more than three terminals.
The plurality of package portions are separated in a singulation step to obtain an electronic package 1 as shown in
As described above, support portion 8b may have the second part and the third part at their respective second and third vertical positions. Part of the body may be removed thereby exposing a surface of the second part to an outside of the body. As a result of the singulation operation, first and second package terminals 13a, 13b have a second thickness near an edge or periphery of electronic package 1 that is less than a first thickness away from the edge or periphery of electronic package 1. For example, package terminals 13a, 13b have the first thickness closer to semiconductor die 3.
In the embodiment shown in
First conductive mechanical support 8 may for example comprise a conductive metal such as copper. Further processing steps may be applied, such as plating package terminals 13a, 13b, for example with tin, to enable better soldering conditions.
In
Similarly to first conductive mechanical support 8 of
In the embodiment shown in
Similarly to
In
A second conductive mechanical support 9 may be provided for multiple or each package portion of the plurality of package portions. To that end, second mold portion 6b may be brought into contact with each of said second conductive mechanical supports 9.
It is noted that both first conductive mechanical support(s) 8 of
In
In
It is noted that protruding mold portions 6c may be applied concurrently with first conductive mechanical support 8 of
In
Conductive clip 15 may be provided in a further lead frame (not shown) during the manufacturing process, and may be fixedly attached to at least one metal layer of the metal layer stack and electrically connected to a corresponding terminal of semiconductor die 3. Conductive clip 15 (or a stack of multiple conductive clips 15) may aid in the cooling of semiconductor die 3 during operation, that is, it may at least partially function as part of a heatsink.
Although conductive clip 15 is shown to form part of the second electrical contact, its concept may similarly be applied to the first electrical contact or further terminals of semiconductor die 3. For example, conductive clip 15 may instead be provided to form at least part of the first electrical contact, or a respective conductive clip may be provided to form at least part of each of the first electrical contact, the second electrical contact, and optionally any further electrical contacts of semiconductor die 3.
Here, it is noted that the embodiments in
In the above description, electronic packages are described that have at least two terminals. For example, semiconductor die 3 may have a circuit integrated thereon that has two terminals, such as various types of diodes or other combinations of circuits. However, the present disclosure is not limited thereto. Electronic packages according to the present disclosure, and manufacturing methods thereof, could instead have three terminals or even more than three terminals. For example, semiconductor die 3 may have a transistor integrated thereon, such as a metal-oxide-semiconductor field effect transistor (MOSFET), a bipolar junction transistor (BJT), an insulated-gate bipolar transistor (IGBT), or the like. Semiconductor die 3 may have a thyristor or silicon-controlled rectifier (SCR) integrated thereon. To that end, the electronic packages according to the present disclosure may have further package terminals and its semiconductor die may have further electrical contacts. Such electrical contacts may be electrically connected to corresponding further package terminals via further first conductive mechanical supports, or via further clips or further bondwires as appreciated by the skilled person.
Semiconductor die 3 may be based on any of silicon, silicon carbide, gallium arsenide or gallium nitride technology, or the like, as will be understood by the skilled person.
The ensuing description above provides preferred exemplary embodiment(s) only, and is not intended to limit the scope, applicability, or configuration of the disclosure. Rather, the ensuing description of the preferred exemplary embodiment(s) will provide those skilled in the art with an enabling description for implementing a preferred exemplary embodiment of the disclosure, it being understood that various changes may be made in the function and arrangement of elements, including various modifications and/or combinations of features from different embodiments, without departing from the scope of the present disclosure as defined by the appended claims.
Number | Date | Country | Kind |
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22193335.1 | Aug 2022 | EP | regional |