DFN / QFN packaging device with hidden cooling fins

Abstract

The utility model relates to a DFN / QFN packaging device with a hidden radiating fin. The DFN / QFN packaging device comprises a plastic packaging material layer, and a base island, a chip, a lead, a pin and an insulating spacer which are arranged in the plastic packaging material layer, the chip is located on the base island, and the chip and the base island are bonded through a first bonding material layer; the pins are located on the two sides of the base island, gaps are formed between the pins on the two sides and the base island, and the chip is electrically connected with the pins through leads; the insulating spacer is located below the base island, and the insulating spacer and the base island are bonded through a second bonding material layer. According to the DFN / QFN packaging device capable of hiding the cooling fin, the insulating spacer is bonded below the base island, and the spacer is made of an insulating material, so that a short circuit caused by direct contact or high-voltage breakdown of the cooling fin and a circuit below the base island when the DFN / QFN packaging device is assembled with a carrier plate can be avoided, and the problems of frame deformation and non-sticky bonding wires caused by suspension below the base island can be avoided; and the plastic package is not filled.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductors, in particular to a DFN / QFN packaging device with a hidden heat sink. Background Art

[0002] Conventional DFN / QFN product designs usually have the bottom of the pins and the bottom of the island exposed. Figure 1 As shown, it generally includes a molding material layer 1 and a base island 2, a chip 3, a lead 4 and a pin 5 inside the molding material layer 1. The chip 3 is located on the base island 2, and the chip 3 and the pin 5 are electrically connected through the lead 4. The chip 3 and the base island 2 are bonded by an adhesive material 6. The pin 5 is located on both sides of the base island 2, and there is a gap between the pins 5 on both sides and the base island 2. Because some carriers will be designed with circuits under the heat sink of DFN / QFN products, in order to avoid direct contact between the heat sink and the circuit below when the DFN / QFN product is assembled with the carrier or to prevent the circuit from short-circuiting due to high voltage breakdown, a DFN / QFN product without a heat sink will be required. Only the bottom of the pin is required to be exposed, and the base island and the chip are encapsulated in the molding material. The usual practice for this type of design is to half-etch the base island, that is, the material thickness of the base island is half the thickness of the entire lead frame, such as Figure 2 As shown in the figure, this design is in a suspended state below the base island that supports the chip. Therefore, during the processing, problems such as lead frame deformation, wire bonding failure, wire breakage, and unfilled plastic package (A) are very likely to occur. Utility Model Content

[0003] The following is a brief overview of embodiments of the present invention to provide a basic understanding of certain aspects of the invention. It should be understood that the following summary is not an exhaustive overview of the invention. It is not intended to identify key or important aspects of the invention, nor is it intended to limit the scope of the invention. Its purpose is simply to present certain concepts in a simplified form as a prelude to the more detailed description discussed later.

[0004] To address the above problems, the idea of ​​the present invention is to bond an insulating gasket under the base island. The gasket is made of insulating material, which can avoid circuit short circuits caused by direct contact between the heat sink and the circuit below or high voltage breakdown when assembled with the carrier board. It can also prevent frame deformation, solder wire failure, wire breakage, and plastic sealing failure caused by the overhanging below the base island.

[0005] Specifically, the utility model provides a DFN / QFN packaging device with a hidden heat sink, which includes a plastic packaging material layer and a base island, a chip, a lead, a pin and an insulating gasket inside the plastic packaging material layer; the chip is located on the base island, and the chip and the base island are bonded by a first adhesive material layer; the pins are located on both sides of the base island, and there is a gap between the pins on both sides and the base island, and the chip and the pins are electrically connected through the leads; the insulating gasket is located under the base island, and the insulating gasket and the base island are bonded by a second adhesive material layer; the lower surface of the insulating gasket and the lower surface of the pin are exposed outside the plastic packaging material layer.

[0006] As a feasible solution, the thickness of the base island is half the thickness of the pin (the thickness of the entire lead frame).

[0007] Furthermore, the upper surface of the base island is flush with the upper surface of the pin.

[0008] Furthermore, the lower surface of the insulating gasket is flush with the lower surface of the pin.

[0009] As another feasible solution, the thickness of the base island is the same as the thickness of the pin.

[0010] Furthermore, the upper surface of the base island is flush with the upper surface of the pin.

[0011] Furthermore, the upper surface of the insulating gasket is flush with the lower surface of the pin.

[0012] Furthermore, electroplated metal layers or tin balls are provided on both sides of the insulating gasket and below the pins. The shape of the tin balls is not limited and can also be replaced by other conductive materials.

[0013] The plastic packaging material layer may wrap both sides of the insulating gasket, or may not wrap both sides of the insulating gasket, so that both sides of the insulating gasket are exposed outside the plastic packaging material layer.

[0014] Preferably, protrusions extend horizontally outward from the upper portions of both sides of the base island, and the pins extend horizontally inward, so that the gaps between the pins and the base island are narrow at the top and wide at the bottom. This gap between the pins and the base island enhances the sealing of the molding compound layer, ensuring the stability and performance of the overall structure.

[0015] The utility model realizes a DFN / QFN packaging device with a hidden heat sink through the above solution. An insulating gasket is bonded under the base island. The gasket is made of insulating material. It can avoid short circuits caused by direct contact between the heat sink and the circuit below or high voltage breakdown when assembled with the carrier board. It can also prevent problems such as frame deformation, wire bonding failure, wire breakage, and unfilled plastic package caused by the overhanging under the base island. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention can be better understood by referring to the following description in conjunction with the accompanying drawings, wherein the same or similar reference numerals are used throughout the drawings to represent the same or similar components. The accompanying drawings, together with the following detailed description, are incorporated into and form a part of this specification and are used to further illustrate the preferred embodiments of the present invention and to explain the principles and advantages of the present invention. In the drawings:

[0017] Figure 1 A schematic diagram of the structure of a conventional DFN / QFN design in the prior art;

[0018] Figure 2 This is a schematic diagram showing the problem of unfilled plastic packaging during the processing of the prior art;

[0019] Figure 3 Schematic diagram showing that the material thickness of the base island in Example 1 is half the thickness of the entire lead frame;

[0020] Figure 4 This is a schematic diagram of the structure of the insulating gasket bonded to the lower surface of the base island in Example 1;

[0021] Figure 5 Schematic diagram of the chip being bonded above the base island in Example 1;

[0022] Figure 6 This is a schematic diagram of connecting a chip to a pin using a lead wire in the production method of Example 1;

[0023] Figure 7 This is a schematic diagram of using a plastic encapsulation compound to protect a chip, leads, and lead frame in the production method of Example 1;

[0024] Figure 8 Schematic diagram of bonding the insulating spacer to the base island in the production method of Example 2;

[0025] Figure 9 Schematic diagram of bonding the chip to the base island in the production method of Example 2;

[0026] Figure 10 This is a schematic diagram of connecting a chip to a pin using a lead wire in the production method of Example 2;

[0027] Figure 11 This is a schematic diagram of using a plastic encapsulation compound to protect a chip, leads, and lead frame in the production method of Example 2;

[0028] Figure 12 Schematic diagram of providing a metal electroplating layer on the lower surface of the pin in the production method of Example 2;

[0029] Figure 13Schematic diagram of placing solder balls on the lower surface of the pins in the production method of Example 2;

[0030] Figure 14 Schematic diagram of bonding the chip to the base island in the production method of Example 3;

[0031] Figure 15 This is a schematic diagram of connecting a chip to a pin using wires in the production method of Example 3;

[0032] Figure 16 This is a schematic diagram of using a plastic encapsulation compound to protect a chip, leads, and lead frame in the production method of Example 3;

[0033] Figure 17 Schematic diagram of bonding the insulating gasket to the base island in the production method of Example 3;

[0034] Figure 18 Schematic diagram of providing a metal electroplating layer on the lower surface of the pin in the production method of Example 3;

[0035] Figure 19 Schematic diagram of placing solder balls on the lower surface of the pins in the production method of Example 3;

[0036] The corresponding numbers of the components in the figure are as follows: base molding material layer 1, base island 2, chip 3, lead 4, pin 5, adhesive material layer 6, base island 101, first adhesive material layer 102, chip 103, lead 104, pin 105, molding material layer 106, insulating gasket 108, second adhesive material layer 109, electroplated metal layer 110, solder ball 111. DETAILED DESCRIPTION

[0037] The following describes embodiments of the present invention with reference to the accompanying drawings. Elements and features described in one drawing or one embodiment of the present invention may be combined with elements and features shown in one or more other drawings or embodiments. It should be noted that for the sake of clarity, the drawings and descriptions omit the representation and description of components and processes that are not relevant to the present invention and are known to those of ordinary skill in the art.

[0038] In the description of the present invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating positions or relationships, are based on the positions or relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0040] Example 1

[0041] In this embodiment, a DFN / QFN packaging device with a hidden heat sink of the utility model includes a plastic packaging material layer 106 and a base island 101, a chip 103, a lead 104, a pin 105 and an insulating gasket 108 inside the plastic packaging material layer 106; the chip 103 is located on the base island 101, and the chip 103 and the base island 101 are bonded by a first adhesive material layer 102; the pins 105 are located on both sides of the base island 101, and there is a gap between the pins 105 on both sides and the base island 101, and the chip 103 and the pins 105 are electrically connected through the leads 104; the insulating gasket 108 is located under the base island 101, and the insulating gasket 108 and the base island 101 are bonded by a second adhesive material layer 109; the lower surface of the insulating gasket 108 and the lower surface of the pin 105 are exposed outside the plastic packaging material layer 106.

[0042] In this embodiment, the thickness of the base island 101 is half the thickness of the pin 105 (the thickness of the entire lead 104 frame). The upper surface of the base island 101 is flush with the upper surface of the pin 105. The lower surface of the insulating spacer 108 is flush with the lower surface of the pin 105.

[0043] Furthermore, protrusions extend horizontally outward from the upper portions of both sides of island 101, while pins 105 extend horizontally inward, creating a narrower gap at the top and wider at the bottom between pins 105 and island 101. This gap between pins 105 and island 101 enhances the sealing properties of molding compound layer 106, ensuring the stability and performance of the overall structure.

[0044] In actual production, an insulating gasket 108 is bonded under the base island 101. The gasket is made of insulating material and can prevent the heat sink from directly contacting the circuit below or causing a short circuit due to high voltage breakdown when assembled with the carrier board. It can also prevent problems such as frame deformation, wire failure, wire breakage, and plastic sealing failure caused by the base island 101 being suspended. The processing method is as follows:

[0045] 1. Half-etch the bottom of the base island 101 of the DFN / QFN frame, that is, the material thickness of the base island 101 is half the thickness of the entire lead 104 frame, such as Figure 3 As shown, the upper surface of the base island 101 is flush with the upper surface of the pin 105;

[0046] 2. Adhere the insulating gasket 108 to the lower surface of the base island 101 by means of adhesive material, such as Figure 4 As shown, the lower surface of the insulating spacer 108 is flush with the lower surface of the pin 105, thus avoiding the base island 101 being in a suspended state during subsequent processing;

[0047] 3. The chip 103 is bonded to the base island 101 by bonding material, such as Figure 5 As shown;

[0048] 4. Connect the chip 103 to the lead 104 frame pin 105 with the lead 104, and lead out the electrical connection through the lead 104, such as Figure 6 As shown;

[0049] 5. Use plastic packaging material to plasticize the chip 103, lead 104, lead 104 frame, and insulating gasket 108 for protection, and expose the lower surface of the insulating gasket 108 and the frame pin 105. Figure 7 shown.

[0050] Example 2

[0051] Different from the embodiment 1, the thickness of the base island 101 in this embodiment is the same as the thickness of the lead 105 .

[0052] The upper surface of the base island 101 is flush with the upper surface of the lead 105 .

[0053] The upper surface of the insulating spacer 108 is flush with the lower surface of the pin 105 .

[0054] In addition, electroplated metal layers or solder balls are provided on both sides of the insulating spacer 108 and below the pins 105 . The shape of the solder balls is not limited and can also be replaced by other conductive materials.

[0055] In actual production, the production and processing methods are as follows:

[0056] 1. Using conventional DFN / QFN design, the insulating spacer 108 is bonded to the bottom of the lead 104 frame base island 101 by adhesive material, as shown in FIG. Figure 8 As shown;

[0057] 2. The chip 103 is bonded to the base island 101 by bonding material, such as Figure 9 As shown;

[0058] 3. Connect the chip 103 to the lead 104 frame pin 105 with the lead 104, and lead out the electrical connection through the lead 104, such as Figure 10 As shown;

[0059] 4. Use plastic packaging material to plasticize the chip 103, lead 104, lead 104 frame, and insulating gasket 108 for protection, and expose the lower surface of the insulating gasket 108 and the frame pin 105. Figure 11 As shown;

[0060] 5. Electroplate a metal plating layer of a certain thickness on the exposed position of the lower surface of the pin 105 so that it is parallel to or higher than the surface of the insulating gasket 108, such as Figure 12 As shown, or a suitable solder ball is implanted at the exposed position on the lower surface of the pin 105, such as Figure 13 As shown, the solder balls can be replaced with other conductive materials and have any shape.

[0061] Example 3

[0062] The molding material layer 106 may or may not wrap both sides of the insulating gasket 108 . In this embodiment, unlike the second embodiment, both sides of the insulating gasket 108 are exposed outside the molding material layer 106 .

[0063] The specific processing methods are as follows:

[0064] 1. Using conventional DFN / QFN design, the chip 103 is bonded to the base island 101 by bonding material, such as Figure 14 As shown;

[0065] 2. Connect the chip 103 to the lead 104 frame pin 105 with the lead 104, and lead out the electrical connection through the lead 104, such as Figure 15 As shown;

[0066] 3. Use plastic packaging material to protect the chip 103, lead 104, and lead 104 frame, and expose the frame pin 105 and the bottom surface of the base island 101. Figure 16 As shown;

[0067] 4. Adhere the insulating gasket 108 to the exposed position on the lower surface of the lead 104 frame base island 101 by means of adhesive material, as shown in FIG. Figure 17 As shown;

[0068] 5. Electroplate a metal plating layer of a certain thickness on the exposed position of the lower surface of the pin 105 so that it is parallel to or higher than the surface of the insulating gasket 108, such as Figure 18 As shown, or a suitable solder ball is implanted at the exposed position on the lower surface of the pin 105, such as Figure 19 As shown, the solder balls can be replaced with other conductive materials and have any shape.

[0069] In the above description of specific embodiments of the present invention, the features described and / or shown for one embodiment can be used in the same or similar manner in one or more other embodiments, combined with the features in other embodiments, or replace the features in other embodiments.

[0070] It should be emphasized that the term "include / comprises" when used herein refers to the existence of features, elements, steps or components, but does not exclude the existence or addition of one or more other features, elements, steps or components.

[0071] Although the present invention has been disclosed above through the description of specific embodiments of the present invention, it should be understood that all the above embodiments and examples are illustrative rather than restrictive. Those skilled in the art may design various modifications, improvements, or equivalents of the present invention within the spirit and scope of the appended claims. Such modifications, improvements, or equivalents should also be considered to be included within the scope of protection of the present invention.

Claims

1. A DFN / QFN package device with a hidden heat sink, characterized by: It includes a plastic packaging material layer and a base island, a chip, leads, pins and an insulating gasket inside the plastic packaging material layer; the chip is located on the base island, and the chip and the base island are bonded by a first adhesive material layer; the pins are located on both sides of the base island, and there is a gap between the pins on both sides and the base island, and the chip and the pins are electrically connected through the leads; the insulating gasket is located under the base island, and the insulating gasket and the base island are bonded by a second adhesive material layer; the lower surface of the insulating gasket and the lower surface of the pins are exposed outside the plastic packaging material layer.

2. The DFN / QFN packaging device according to claim 1, wherein: The thickness of the base island is half the thickness of the pin.

3. The DFN / QFN packaging device according to claim 2, wherein: The upper surface of the base island is flush with the upper surface of the lead.

4. The DFN / QFN packaging device according to claim 3, wherein: The lower surface of the insulating gasket is flush with the lower surface of the pin.

5. The DFN / QFN packaging device according to claim 1, wherein: The thickness of the base island is the same as the thickness of the pins.

6. The DFN / QFN packaging device according to claim 5, wherein: The upper surface of the base island is flush with the upper surface of the lead.

7. The DFN / QFN packaging device according to claim 6, wherein: The upper surface of the insulating gasket is flush with the lower surface of the pin.

8. The DFN / QFN packaging device according to claim 7, wherein: Electroplated metal layers or solder balls are provided at positions on both sides of the insulating spacer and below the pins.

9. The DFN / QFN packaging device according to claim 1, wherein: Both sides of the insulating gasket are exposed outside the plastic packaging material layer.

10. The DFN / QFN packaging device according to claim 1, wherein: The upper parts of both sides of the base island extend outwardly to form protrusions, and the pins extend inwardly to form protrusions, so that the gaps between the pins on both sides and the base island are narrow at the top and wide at the bottom.

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