This Utility Patent application claims priority to German Patent Application No. 10 2023 135 840.5 filed Dec. 19, 2023, which is incorporated herein by reference.
The present disclosure is related to a semiconductor device comprising a carrier, a semiconductor die disposed on the carrier and a clip connected between the semiconductor die and the carrier.
Power semiconductor packages include a power semiconductor die, in particular a power semiconductor transistor die, connected with a die carrier like a leadframe and embedded in a mold compound. A contact pad of the semiconductor transistor die like, for example, a source pad or a drain pad, is connected via a connector element with a die pad or a lead of the leadframe. Due to the high currents of up to 10A and higher flowing in the load path of the semiconductor transistor, the selection of a suitable connection element and its connection to the semiconductor die as well as to the leadframe is of very high importance.
A first aspect of the present disclosure is related to a semiconductor device comprising a carrier, a semiconductor die disposed on the carrier and comprising a first contact pad on a first main face remote from the carrier, and a clip, wherein the clip comprises a horizontal portion, a vertical portion, and a bent-back portion.
The accompanying drawings are included to provide a further understanding of embodiments and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and together with the description serve to explain principles of embodiments. Other embodiments and many of the intended advantages of embodiments will be readily appreciated as they become better understood by reference to the following detailed description.
The elements of the drawings are not necessarily to scale relative to each other. Like reference numerals designate corresponding similar parts.
A first aspect of the present disclosure is related to a semiconductor device comprising a carrier, a semiconductor die disposed on the carrier and comprising a first contact pad on a first main face remote from the carrier, and a clip, wherein the clip comprises a horizontal portion, a vertical portion, and a bent-back portion.
Due to its dimensions and its coupling with the carrier, the clip enables very high currents flowing through the load path of the transistor to be passed on. In particular, the clip may have a C-shape in which the bent-back portion is formed as a horizontal bar and thus rests on the die carrier with its entire lower surface. The carrier may further comprise a carrier connection portion for connecting with the bent-back portion of the clip and thus further increasing the coupling between the clip and the carrier. Another advantage of a clip shaped as described is that the clip is shorter when viewed from the side than a non-bent clip, providing additional space for larger semi-conductors.
According to an embodiment of the semiconductor device of the first aspect, the carrier comprises a leadframe comprising a die pad and one or more leads. The clip can be connected with the die pad and the further clip can be connected to a lead.
According to another embodiment the carrier can also be one of a direct copper bond (DCB), an active metal braze (AMB), or an isolated metal substrate (IMS).
According to an embodiment of the semiconductor device of the first aspect, the semiconductor device further comprises an encapsulant covering at least parts of the semiconductor die, the carrier, and the clip. According to an example thereof, the encapsulant covers an outer sidewall of the vertical portion of the clip. In case of the carrier being a leadframe with a die pad and one or more leads, the encapsulant can also be filled in between the die pad and the one or more leads and also between the leads.
According to an embodiment of the semiconductor device of the first aspect, a surface of the horizontal portion of the clip is exposed to the outside thus allowing top side cooling by attaching a suitable heatsink on the surface of the horizontal portion.
According to an embodiment of the semiconductor device of the first aspect, the semiconductor die comprises a semiconductor transistor die. According to further examples thereof, the semiconductor die comprises one or more of a horizontal semiconductor transistor die, a vertical semiconductor transistor die, a semiconductor power transistor die, an IGBT die, a MOSFET die, a CoolMOS die, a wide band gap semiconductor transistor die, in particular a SiC transistor die or a GaN transistor die.
According to an embodiment of the semiconductor device of the first aspect, the semiconductor die comprises only one contact pad on the first main face. This can in particular be the case if the semiconductor die is a vertical semiconductor transistor die comprising a source pad on the first upper main face and a drain pad on the second lower main face, or in a so-called source-down configuration a drain pad on the first upper main face and a source pad on the second lower main face.
According to an embodiment of the semiconductor device of the first aspect, the semiconductor die comprises a second contact pad on the first main face. This can in particular be the case if the semiconductor die is a horizontal MOSFET die comprising a source pad and a drain pad both being disposed on the first upper main face of the semiconductor die.
According to an embodiment of the semiconductor device of the first aspect, the semiconductor device further comprises a second clip connected between the second contact pad and the carrier. According to an example thereof, the second clip can be similar in shape to the first clip.
A second aspect of the present disclosure is related to a method for fabricating a semiconductor device, the method comprising providing a carrier, disposing a semiconductor die on the carrier, the semiconductor die comprising a first contact pad on a first main face remote from the carrier, providing a clip comprising a horizontal portion, a horizontal portion, an adjoining vertical portion, and an adjoining a bent-back portion connected with the carrier, and connecting the clip between the semiconductor die and the carrier by connecting the horizontal portion with the contact pad and the bent-back portion with the carrier.
According to an embodiment of the method of the second aspect, providing the carrier comprises forming a carrier connection portion into the carrier, the carrier connection portion being configured to connect with the bent-back portion of the clip. According to an example thereof, the carrier connection portion comprises a recess which may be formed by one of coining, milling or etching.
According to an embodiment of the method of the second aspect, the method further comprising covering at least parts of the semiconductor die, the carrier, and the clip with an encapsulant. According to an example thereof, the method further comprises covering an outer sidewall of the vertical portion of the clip with the encapsulant.
According to an embodiment of the method of the second aspect, in case of a second contact pad on a first upper main face of the semiconductor die, the method further comprises connecting a second clip between the second contact pad and the die pad or a lead. The second clip can have a similar shape like the first clip.
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the disclosure may be practiced. In this regard, directional terminology, such as “top”, “bottom”, “front”, “back”, etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims.
It is to be understood that the features of the varius exemplary embodiments described herein may be combined with each other, unless specifically noted otherwise.
As employed in this specification, the terms “bonded”, “attached”, “connected”, “coupled” and/or “electrically connected/electrically coupled” are not meant to mean that the elements or layers must directly be contacted together; intervening elements or layers may be provided between the “bonded”, “attached”, “connected”, “coupled” and/or “electrically connected/electrically coupled” elements, respectively. However, in accordance with the disclosure, the above-mentioned terms may, optionally, also have the specific meaning that the elements or layers are directly contacted together, i.e. that no intervening elements or layers are provided between the “bonded”, “attached”, “connected”, “coupled” and/or “electrically connected/electrically coupled” elements, respectively.
Further, the word “over” used with regard to a part, element or material layer formed or located “over” a surface may be used herein to mean that the part, element or material layer be located (e.g. placed, formed, deposited, etc.) “indirectly on” the implied surface with one or more additional parts, elements or layers being arranged between the implied surface and the part, element or material layer. However, the word “over” used with regard to a part, element or material layer formed or located “over” a surface may, optionally, also have the specific meaning that the part, element or material layer be located (e.g. placed, formed, deposited, etc.) “directly on”, e.g. in direct contact with, the implied surface.
The leadframe 11 as shown in
In the embodiment described above the bent-back portion 13C comprises a flat lower surface and rests completely in the recess 11A.1 or 11B.1, see also
In another embodiment the carrier connection portion comprises a strip-like elevation on an upper surface of the carrier and the bent-back portion comprises a recess with dimensions slightly bigger than the strip-like elevation of the carrier, wherein the strip-like elevation engages with the slot when connecting the bent-back portion with the carrier, see also
In particular,
The semiconductor die 12 is, for example, a lateral MOSFET die comprising source pad 12A and drain pad 12B on one and the same first upper main face of the semiconductor die 12.
The encapsulant 14 or 24 may be comprised of a conventional mold compound like, for example, a resin material, in particular an epoxy resin material. Moreover, the encapsulant 14 can be made of a thermally conductive material to allow efficient heat dissipation to external application heat sinks. The material of the encapsulant 14 can, in particular, comprise a resin like an epoxy resin material filled with particles like, for example, SiO or other ceramic particles, or thermally conductive particles like, for examples, Al2O3, BN, AlN, Si3N4, diamond, or any other thermally conductive particles.
Hence in both devices 30 and 40 the semiconductor die 32 or 42 is connected with its backside with the die pad 11A and there is only one clip 16 which is connected between the contact pad at the upper main face and a lead 11B of the carrier 11. The clip 16 comprises a C shape on the right hand side, and in particular a horizontal portion 16A, a first vertical portion 16B connected with the horizontal portion 16A on its right hand side, a horizontal bent-back portion 16C which is connected with the first vertical portion 16B and which is connected with the source pad of the semiconductor die 32 according to
In all the embodiments shown in
In the following specific examples of the present disclosure are described.
Example 1 is a semiconductor device comprising a semiconductor die disposed on the carrier and comprising a first contact pad on a first main face remote from the carrier, and a clip connected between the contact pad and the carrier, wherein the clip comprises a horizontal portion, a vertical portion, and a bent-back portion.
Example 2 is a semiconductor device according to Example 1, wherein the horizontal portion is connected with the contact pad, and the bent-back portion is connected with the carrier.
Example 3 is a semiconductor device according to Example 1, wherein the clip further comprises a further vertical portion which is connected with the horizontal portion and with a portion of the carrier, and wherein the bent-back portion is connected with the contact pad.
Example 4 is a semiconductor device according to any one of the preceding Examples, wherein the carrier comprises a leadframe comprising a die pad and one or more leads.
Example 5 is a semiconductor device according to any one of the preceding Examples, further comprising an encapsulant covering at least parts of the semiconductor die, the carrier, and the clip.
Example 6 is a semiconductor device according to Example 5, wherein the encapsulant covers an outer sidewall of the vertical portion of the clip.
Example 7 is a semiconductor device according to Example 3 or 4, wherein the bent-back portion is covered by the encapsulant.
Example 8 is a semiconductor device according to any one of the preceding Examples, wherein the carrier comprises a carrier connection portion for connecting with the bent-back portion of the clip.
Example 9 is a semiconductor device according to Example 8, wherein the carrier connection portion comprises a recess for receiving the bent-back portion of the clip.
Example 10 is a semiconductor device according to any one of the preceding Examples, wherein a surface of the horizontal portion of the clip is exposed to the outside.
Example 11 is a semiconductor device according to any one of the preceding Examples, wherein the bent-back portion of the clip comprises a horizontal shape.
Example 12 is a semiconductor device according to any one of the preceding Examples, wherein the semiconductor die comprises a semiconductor transistor die.
Example 13 is a semiconductor device according to Example 12, wherein the semiconductor die comprises one or more of a horizontal semiconductor transistor die, a vertical semiconductor transistor die, a semiconductor power transistor die, an IGBT die, a MOSFET die, a CoolMOS die, a wide band gap semiconductor transistor die, in particular a SiC transistor die or a GaN transistor die.
Example 14 is a semiconductor device according to any one of the preceding Examples, wherein the semiconductor die comprises a second contact pad on the first main face.
Example 15 is a semiconductor device according to Example 14, further comprising a further clip connected between the second contact pad and the carrier.
Example 16 is a semiconductor device according to Example 15, wherein the carrier comprises a leadframe comprising a die pad and one or more leads, and the clip is connected with the die pad and the further clip is connected to a lead.
Example 16 is a semiconductor device Example 15 or 16, wherein the further clip is similar in shape to the clip.
Example 17 is a method for fabricating a semiconductor device, the method comprising providing a carrier, disposing a semiconductor die on the carrier, the semiconductor die comprising a first contact pad on a first main face remote from the carrier, providing a clip comprising a horizontal portion, a horizontal portion, an adjoining vertical portion, and an adjoining a bent-back portion connected with the carrier, and connecting the clip between the semiconductor die and the carrier by connecting the horizontal portion with the contact pad and the bent-back portion with the carrier.
Example 19 is a method according to Example 18, wherein providing the carrier comprises forming a carrier connection portion into the carrier, the recess being configured to connect with the bent-back portion of the clip.
Example 20 is a method according to Example 19, wherein the carrier connection portion comprises a recess configured to receive the bent-back portion of the clip.
Example 21 is a method according to Example 20, wherein forming the recess comprises one of coining, milling or etching.
Example 22 is a method according to any one of Examples 17 to 21, further comprising covering at least parts of the semiconductor die, the carrier, and the clip with an encapsulant.
Example 23 is a method according to Example 20, further comprising covering an outer sidewall of the vertical portion of the clip with the encapsulant.
In addition, while a particular feature or aspect of an embodiment of the disclosure may have been disclosed with respect to only one of several implementations, such feature or aspect may be combined with one or more other features or aspects of the other implementations as may be desired and advantageous for any given or particular application. Furthermore, to the extent that the terms “include”, “have”, “with”, or other variants thereof are used in either the detailed description or the claims, such terms are intended to be inclusive in a manner similar to the term “comprise”. Furthermore, it should be understood that embodiments of the disclosure may be implemented in discrete circuits, partially integrated circuits or fully integrated circuits or programming means. Also, the term “exemplary” is merely meant as an example, rather than the best or optimal. It is also to be appreciated that features and/or elements depicted herein are illustrated with particular dimensions relative to one another for purposes of simplicity and ease of understanding, and that actual dimensions may differ substantially from that illustrated herein.
Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this disclosure be limited only by the claims and the equivalents thereof.
Number | Date | Country | Kind |
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10 2023 135 840.5 | Dec 2023 | DE | national |