Signal isolation transmission packaging structure and isolator

Abstract

The invention provides a signal isolation transmission packaging structure and an isolator. The packaging structure comprises a first base island, a second base island, a first chip, a second chip, a first transceiving unit, a second transceiving unit and a first plastic package body, the first chip and the first transceiver unit are arranged on the first base island; the first chip, the first transceiver unit, the first base island and the second base island are plastically packaged in the first plastic package body; the second chip and the second transmit-receive unit are arranged on the first plastic package body, and the second transmit-receive unit corresponds to the first transmit-receive unit in the stacking direction of the package structure. According to the invention, vertical face-to-face isolation transmission is realized by adopting a vertical stacking mode, so that the size of the packaging structure can be reduced, and the isolation transmission performance can be optimized.

Description

Technical Field

[0001] The present invention relates to the field of packaging technology, and in particular to a signal isolation transmission packaging structure and an isolator. Background Art

[0002] The existing signal isolation transmission structure usually adopts the traditional frame packaging, and its structure is as follows Figure 1 As shown, the chip in the packaging structure is bonded to two independent frame base islands on the left and right in a flat manner, connected by wire bonding, and then plastic-sealed as a whole to form a finished packaged chip with the function of isolating and transmitting signals on both sides.

[0003] The isolation strength of the above-mentioned existing signal isolation transmission packaging structure depends on the base island spacing, and the overall size of the packaging structure is relatively large; furthermore, the direction of its isolation transmission path is single and is dependent on the frame; in addition, its wiring is relatively complex, so the wiring parasitic parameters are large, which can easily affect the coupling performance of the isolation transmission. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a signal isolation transmission packaging structure and an isolator, which can reduce the size of the packaging structure and optimize the isolation transmission performance.

[0005] In order to solve the above technical problems, the first technical solution adopted by the present invention is:

[0006] A signal isolation transmission packaging structure comprises: a first base island, a second base island, a first chip, a second chip, a first transceiver unit, a second transceiver unit and a first plastic package; the first base island and the second base island are separated by a preset distance;

[0007] The first chip and the first transceiver unit are arranged on the first base island; the first chip, the first transceiver unit, the first base island and the second base island are plastic-encapsulated in the first plastic encapsulation body;

[0008] The second chip and the second transceiver unit are disposed on the first plastic package body, and the second transceiver unit corresponds to the first transceiver unit in a stacking direction of the packaging structure.

[0009] Optionally, it further includes a soldering pad; the soldering pad is arranged on the first plastic package body and is connected to the second base island; the second chip is connected to the second base island through the soldering pad.

[0010] Optionally, in a stacking direction of the package structure, the second chip, the pad and the second base island correspond to each other.

[0011] Optionally, in the stacking direction of the package structure, the pad corresponds to the second base island, and the pad is staggered with the second chip; and the second chip is connected to the pad by wire bonding.

[0012] Optionally, part of the second base island is plastic-encapsulated in the first plastic encapsulation body; and the second chip is connected to the un-plastic-encapsulated part of the second base island through wire bonding.

[0013] Optionally, the first transceiver unit, the first chip and the first base island are connected in sequence through wire bonding; and the second transceiver unit is connected to the second chip through wire bonding.

[0014] Optionally, the first chip and the first transceiver unit are arranged on the first base island in a flat manner, and / or the second chip and the second transceiver unit are arranged on the first plastic package in a flat manner.

[0015] Optionally, it further includes a second plastic package; the first plastic package, the second chip and the second transceiver unit are plastic-sealed in the second plastic package.

[0016] Optionally, the first transceiver unit is an antenna or a coil; the second transceiver unit is an antenna or a coil.

[0017] Another technical solution provided by the present invention is:

[0018] An isolator comprises the above-mentioned signal isolation transmission packaging structure.

[0019] The beneficial effect of the present invention is that: the present invention plastic-seales the secondary structure on one side in the first plastic sealing body, and the secondary side structure is arranged above the first plastic sealing body in a vertical stacking manner, and the first transceiver unit in the primary side structure corresponds to the second transceiver unit in the secondary side structure in the stacking direction. Thus, not only can the effective isolation transmission between the primary side and the secondary side be guaranteed; but also the vertical stacking structure design can shorten the signal path, so that the transmission matching performance is guaranteed, and can meet the requirements of various isolation transmission path directions and isolation strength by adjusting the thickness of the first plastic sealing body without increasing the floor space, and further, the size of the packaging structure in the horizontal direction can be significantly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the signal isolation transmission packaging structure of the prior art;

[0021] Figure 2 A schematic diagram of a signal isolation transmission package structure provided in an embodiment of the present invention Figure 1 ;

[0022] Figure 3A schematic diagram of a signal isolation transmission package structure provided in an embodiment of the present invention Figure 2 ;

[0023] Figure 4 A schematic diagram of a signal isolation transmission package structure provided in an embodiment of the present invention Figure 3 ;

[0024] Figure 5 for Figure 2 A schematic diagram of the process flow of manufacturing the signal isolation transmission packaging structure shown;

[0025] Figure 6 for Figure 3 and Figure 4 Schematic diagram of the process manufacturing flow of the signal isolation transmission packaging structure shown.

[0026] Description of labels:

[0027] 10. first plastic sealing body; 20. second plastic sealing body;

[0028] 11. first base island; 12. first chip; 13. first transceiver unit; 14. pad;

[0029] 21. Second base island; 22. Second chip; 23. Second transceiver unit; 24. Unsealed part. DETAILED DESCRIPTION

[0030] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

[0031] Embodiment 1

[0032] Please refer to Figure 2 and Figure 3 , this embodiment provides a signal isolation transmission packaging structure, including: a first base island 11, a second base island 21, a first chip 12, a second chip 22, a first transceiver unit 13, a second transceiver unit 23 and a first plastic package 10; the first base island 11 and the second base island 21 are separated by a preset distance;

[0033] The first chip 12 and the first transceiver unit 13 are disposed on the first base island 11. Preferably, the first chip 12 and the first transceiver unit 13 are disposed on the first base island 11 in a tiled manner.

[0034] The first chip 12, the first transceiver unit 13, the first base island 11 and the second base island 21 are plastic-encapsulated in the first plastic encapsulation body 10;

[0035] The second chip 22 and the second transceiver unit 23 are arranged on the first plastic package 10, and the second transceiver unit 23 corresponds to the first transceiver unit 13 in the stacking direction of the package structure. Preferably, the second chip 22 and the second transceiver unit 23 are arranged on the first plastic package 10 in a flat manner.

[0036] In this embodiment, the stacking direction refers to the layer stacking direction of the packaging structure, that is, the Z-axis direction of the packaging structure. Assuming that the layer where the first base island and the second base island are located is the first layer, the layer where the first chip and the first transceiver unit laid flat on the first base island are located is the second layer stacked on the first layer, and so on, by stacking in the Z-axis direction of the overall structure to form a vertically stacked packaging structure.

[0037] In this embodiment, the second transceiver unit corresponds to the first transceiver unit in the stacking direction of the packaging structure, which means that the signal transmission and reception directions of the first transceiver unit and the second transceiver unit correspond in the Z-axis direction of the packaging structure. It can also be understood that the second transceiver unit needs to be arranged directly above the first transceiver unit. This layout design can ensure the best isolation transmission effect between the primary side and the secondary side.

[0038] In this embodiment, the primary side structure includes a first chip, a first transceiver unit and a first base island; the secondary side structure includes a second chip, a second transceiver unit and a second base island. The primary side structure performs wireless isolation transmission of signals through the first transceiver unit and the second transceiver unit of the secondary side structure; the first base island and the second base island serve as carriers for isolation transmission.

[0039] It can be understood that the signal isolation transmission packaging structure provided in this embodiment realizes effective isolation transmission between the primary side structure and the secondary side structure in the stacking direction in a vertical stacking manner, and can also shorten the signal path to ensure the transmission matching performance. It can also meet the requirements of various isolation transmission path directions and isolation strengths by adjusting the thickness of the first plastic package without increasing the footprint. Furthermore, the size of the packaging structure in the horizontal direction can be significantly reduced.

[0040] In some specific implementations of this embodiment, the first transceiver unit is an antenna or a coil; the second transceiver unit is an antenna or a coil. In particular, the first transceiver unit and the second transceiver unit can also be directly implemented by electroplating on the first plastic package.

[0041] In some specific implementations of this embodiment, Figure 2 and Figure 3As shown, the packaging structure also includes a second plastic package 20; the first plastic package 10, the second chip 22 and the second transceiver unit 23 are plastic-encapsulated in the second plastic package 20. Here, the first plastic package 10 not only plays the role of fixing the first chip 12 and the first transceiver unit 13, but also plays the role of physically isolating the primary side structure from the secondary side structure. In particular, by adjusting the thickness of the second plastic package, the "isolation distance" between the primary side structure and the secondary side structure can be adjusted, and then the isolation strength can be adjusted. The second plastic package plays the role of fixing the secondary side structure and the overall packaging structure.

[0042] Embodiment 2

[0043] Please refer to Figures 2 to 4 This embodiment further expands the signal isolation transmission packaging structure provided in the first embodiment, and specifically describes the connection method of the secondary side structure.

[0044] It can be understood that in the signal isolation transmission packaging structure provided in Example 1, the first chip, the first transceiver unit and the first base island in the primary side structure need to be connected in sequence; the second chip, the second transceiver unit and the second base island in the secondary side structure need to be connected in sequence.

[0045] In some specific implementations of this embodiment, Figures 2 to 4 As shown, before the first chip 12, the first transceiver unit 13 and the first base island 11 in the primary side structure are plastic-sealed in the first plastic package 10, a connection relationship between the first chip 12 and the first transceiver unit 13, and a connection relationship between the first transceiver unit 13 and the first base island 11 can be established by wire bonding. Here, since the first chip 12 and the first transceiver unit 13 are at the same level, and the first chip 12 and the first base island 11 are in the same plastic package, it is easier to implement the connection relationship by wire bonding in terms of process and the operation is more convenient.

[0046] In some other specific implementations of this embodiment, other methods may be used to establish a connection relationship between the first chip and the first base island in the primary side structure. For example, a solder pad may be led out by punching and electroplating on the surface of the first base island to connect the first chip; or, the first chip directly uses a flip chip with built-in solder joints, and the solder joints of the flip chip are ground flat and then connected to the first base island as solder pads.

[0047] In some specific implementations of this embodiment, Figures 2 to 4 As shown, the second transceiver unit 23 in the secondary side structure can also be connected to the second chip 22 by wire bonding. Similarly, the second chip 22 and the second transceiver unit 23 are at the same level, so it is easier to implement the connection relationship by wire bonding in terms of process and more convenient to operate.

[0048] In particular, in this embodiment, the second chip and the second base island in the secondary side structure are at different levels and are located in different plastic packages. Therefore, for the connection method between the second chip and the second base island, this embodiment provides the following two feasible specific implementation methods:

[0049] (1) The second chip is connected to the second base island through wire bonding

[0050] like Figure 2 As shown, in this specific embodiment, the packaging structure does not need to be additionally provided with a solder pad 14, but only needs to reserve a wire bonding position in advance when the first plastic sealing is performed to form the first plastic sealing body 10. That is, when the first plastic sealing is performed, only a part of the second base island 21 is plastic sealed in the first plastic sealing body 10, and a part is reserved without plastic sealing, referred to as the un-plastic sealed part 24. Afterwards, the connection between the second chip 22 and the second base island 21 can be achieved by connecting the second chip 22 to the un-plastic sealed part 24 on the second base island 21 by wire bonding during the wire bonding stage. It is preferred that the part of the second base island 21 opposite to the first base island 11 is plastic sealed in the first plastic sealing body 10, and the part opposite to the first base island 11 is not plastic sealed, so as to make the layout of the connection line more reasonable.

[0051] It can be understood that the above layout design that only requires wire bonding does not require the support of special processes. It only requires changing the size of the first plastic package to ensure that the first plastic package can provide a carrier for the second chip and the second transceiver unit on the secondary side while reserving space for the second chip to bond wires. Therefore, compared with the layout design that requires additional pad connection, it can save the step of making pads in the process flow, and does not need to add additional new steps to achieve the connection between the second chip and the second base island, thus having the advantage of simplifying the implementation process.

[0052] (2) The second chip is connected to the second base island via a pad

[0053] like Figure 3 and Figure 4 As shown, in this specific embodiment, the packaging structure further includes a pad 14; the pad 14 is provided on the first plastic package body 10 and is connected to the second base island 21. It can be understood that one end of the pad 14 is connected to the surface of the first plastic package body 10 where the second chip 22 is located, and the other end is connected to the second base island 21. Preferably, the pad is a vertical pad, that is, perpendicular to each level of the packaging structure, and can also be understood as being consistent with the stacking direction.

[0054] Based on the above pad settings, such as Figure 3As shown, for the layout design in which the second chip 22 and the second base island 21 are staggered in the stacking direction of the package structure, the pad 14 can be set to correspond to the second base island 21. That is, in the stacking direction of the package structure, the second chip 22 and the pad 14 are staggered, and the pad 14 is set corresponding to the second base island 21. In this case, in the wire bonding stage, the second chip 22 on the first plastic package 10 can first be connected to one end of the pad 14 located on the first plastic package 10 by wire bonding, and then connected to the second base island 21 via the other end of the pad 14, so that the connection is more reasonable.

[0055] Based on the above pad settings, such as Figure 4 As shown, for the layout design in which the second chip 22 and the second base island 21 are arranged correspondingly in the stacking direction of the package structure, the pad 14 can be directly arranged between the second chip 22 and the second base island 21. That is, the second chip 22, the pad 14 and the second base island 21 are arranged correspondingly in the stacking direction. In this case, the second chip 22 on the first plastic package 10 can be directly connected to the second base island 21 via the pad 14, which can reduce one connection line in the wire bonding process.

[0056] It is understandable that the above Figure 4 In the stacking direction of the packaging structure shown, the second chip 22, the solder pad 14 and the second base island 21 are arranged correspondingly. The second chip 22 can be directly connected to the second base island 21 through the solder pad 14. The connection design can reduce the connection lines, which will help to further reduce the size of the packaging structure in the horizontal direction, making the packaging structure more compact as a whole and more conducive to the miniaturization design of the packaging structure.

[0057] Embodiment 3

[0058] This embodiment is further expanded on the basis of the second embodiment and provides its process flow.

[0059] See also Figure 5 , corresponding to Figure 2 The process flow of the signal isolation transmission packaging structure shown includes:

[0060] S1: Make the framework;

[0061] S2: First chip placement: placing a first chip and a first transceiver unit on the first base island by bonding or other methods;

[0062] S3: First bonding: For the primary side structure, bonding is performed to connect the first chip with the first transceiver unit, and the first transceiver unit with the first base island;

[0063] S4: First plastic encapsulation: The first plastic encapsulation body is formed by plastic encapsulation methods such as injection molding. Here, it should be noted that this plastic encapsulation only encapsulates the front part of the second base island, and the part encapsulated into the first plastic encapsulation body needs to ensure that it can provide a carrier for the second chip and the second transceiver unit on the secondary side; the rear part of the second base island is not plastic encapsulated, and the reserved un-plasticized part only needs to meet the space for the second chip to be wired.

[0064] S5: Second core loading: The second chip and the second transceiver unit are arranged on the first plastic package by bonding or other methods; here, the second transceiver unit needs to correspond to the first transceiver unit in the first plastic package in the stacking direction, that is, it is located directly above the first transceiver unit to ensure the best isolation transmission effect.

[0065] S6: Second wire bonding: For the secondary side structure, wire bonding is performed to connect the second chip with the second transceiver unit, and the second chip with the un-plasticized portion on the second base island.

[0066] S7: Second plastic packaging: Wrap the first plastic packaging body, the second chip, the second transceiver unit and the un-plasticized part on the second base island by injection molding or other plastic packaging methods to form a second plastic packaging body. Here, the un-plasticized part during the first plastic packaging is plastic-sealed by the second plastic packaging body, so as to ensure that the overall packaging structure has the greatest degree of stability.

[0067] S8: cutting and forming.

[0068] The above process flow realizes effective isolation and transmission of the primary side structure and the secondary side structure in the vertical direction by adopting a vertically stacked layout design method for the first plastic package body with the primary side structure and the second plastic package body with the secondary side structure; at the same time, by reserving space on the second base island during the first plastic package to connect the second chip and the second base island located in different plastic packages with wires. The signal isolation transmission packaging structure made by the above process can not only ensure effective isolation and transmission between the primary side and the secondary side, but also shorten the signal path to ensure the transmission matching performance; and can meet the requirements of various isolation transmission path directions and isolation strength by adjusting the thickness of the first plastic package body without increasing the floor space; and can significantly reduce the size of the packaging structure in the horizontal direction; and can also ensure the effective and stable connection between the second chip and the second base island located in different plastic packages, and simplify the manufacturing process, thereby realizing the secondary side function of isolation transmission.

[0069] See also Figure 6 ,correspond Figure 3 and Figure 4 The process flow of the signal isolation transmission packaging structure shown includes:

[0070] S1: Make the framework;

[0071] S2: First chip placement: placing a first chip and a first transceiver unit on the first base island by bonding or other methods;

[0072] S3: First bonding: For the primary side structure, bonding is performed to connect the first chip with the first transceiver unit, and the first transceiver unit with the first base island;

[0073] S4: First plastic packaging: forming a first plastic packaging body by plastic packaging methods such as injection molding, wherein the first plastic packaging body can completely wrap the second base island to ensure that the packaging structure obtains maximum stability.

[0074] S5: Laser + electroplating + surface treatment: A solder joint connected to the second base island is formed by punching holes and electroplating on the upper surface of the first plastic package; then a solder pad is formed by surface treatment. The purpose of this step is to lead the signal of the second chip out from the pin of the second base island through the solder pad.

[0075] S6: Second core loading: The second chip and the second transceiver unit are arranged on the first plastic package by bonding or other methods; here, the second transceiver unit needs to correspond to the first transceiver unit in the first plastic package on the stacking line, that is, it is located directly above the first transceiver unit to ensure the isolation transmission effect; in addition, according to different layout design requirements, the second chip can be staggered with the pad (and the second base island) (such as Figure 6 As shown), it can also be set corresponding to the pad (and the second base island) ( Figure 6 (not shown). These correspond to the two configuration methods of the pads in the second embodiment.

[0076] S7: Second wire bonding: For the secondary side structure, wire bonding is performed to connect the second chip with the second transceiver unit, and the second chip with the pads on the first plastic package.

[0077] S8: Second plastic packaging: Wrap the first plastic packaging body, the second chip and the second transceiver unit by injection molding or other plastic packaging methods to form a second plastic packaging body;

[0078] S9: cutting and forming.

[0079] The above process flow realizes effective isolation and transmission of the primary side structure and the secondary side structure in the vertical direction by adopting a vertically stacked layout design method for the first plastic package body with the primary side structure and the second plastic package body with the secondary side structure; at the same time, the second chip and the second base island located in different plastic packages are connected by adding a pad on the first plastic package body. The signal isolation transmission packaging structure made by the above process can not only ensure effective isolation and transmission between the primary side and the secondary side, but also shorten the signal path to ensure the transmission matching performance; and can meet the requirements of various isolation transmission path directions and isolation strengths by adjusting the thickness of the first plastic package body without increasing the floor space; and can significantly reduce the size of the packaging structure in the horizontal direction; and can also ensure the effective and stable connection between the second chip and the second base island located in different plastic packages, thereby realizing the secondary side function of isolation transmission.

[0080] Embodiment 4

[0081] This embodiment is further extended based on any of the above embodiments to provide an isolator that can achieve face-to-face isolated communication transmission in a vertical direction.

[0082] The isolator provided in this embodiment includes the signal isolation transmission packaging structure described in any one of the above embodiments. The specific structure of the signal isolation transmission packaging structure and its corresponding process flow are not described here in detail. For details, please refer to the description of the above embodiments.

[0083] The isolator provided in this embodiment is formed by plastic-sealing one side of the secondary structure in the first plastic sealing body, and the secondary side structure is arranged above the first plastic sealing body in a vertical stacking manner, and the first transceiver unit in the primary side structure corresponds to the second transceiver unit in the secondary side structure in the stacking direction. Thus, not only can the effective isolation transmission between the primary side and the secondary side be guaranteed, but also the vertical stacking structure design can shorten the signal path to ensure the transmission matching performance, and can meet the requirements of various isolation transmission path directions and isolation strength by adjusting the thickness of the first plastic sealing body without increasing the floor space, and further, the size of the packaging structure in the horizontal direction can be significantly reduced.

[0084] The isolator of this embodiment can be well applied to scenarios requiring wireless isolation transmission, such as high and low voltage wireless isolation in power systems.

[0085] In summary, the signal isolation transmission packaging structure and isolator provided by the present invention adopt a vertical stacking method to realize vertical face-to-face isolation transmission, which can not only ensure effective isolation transmission between the primary side and the secondary side; but also shorten the signal path, so that the transmission matching performance is guaranteed, and can meet the requirements of various isolation transmission path directions and isolation strengths. Furthermore, the size of the packaging structure in the horizontal direction can be significantly reduced.

[0086] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A signal isolation transmission packaging structure, characterized in that: include: A first base island, a second base island, a first chip, a second chip, a first transceiver unit, a second transceiver unit and a first plastic package; The first base island and the second base island are separated by a preset distance; The first chip and the first transceiver unit are arranged on the first base island; the first chip, the first transceiver unit, the first base island and the second base island are plastic-encapsulated in the first plastic encapsulation body; The second chip and the second transceiver unit are disposed on the first plastic package body, and the second transceiver unit corresponds to the first transceiver unit in a stacking direction of the packaging structure.

2. The signal isolation transmission packaging structure according to claim 1, characterized in that: It also includes a soldering pad; the soldering pad is arranged on the first plastic package body and is connected to the second base island; the second chip is connected to the second base island through the soldering pad.

3. The signal isolation transmission packaging structure according to claim 2, characterized in that: In the stacking direction of the package structure, the second chip, the pad and the second base island correspond to each other.

4. The signal isolation transmission packaging structure according to claim 2, characterized in that: In the stacking direction of the package structure, the pad corresponds to the second base island, and the pad is staggered with the second chip; the second chip is connected to the pad by wire bonding.

5. The signal isolation transmission packaging structure according to claim 1, characterized in that: Part of the second base island is plastic-encapsulated in the first plastic encapsulation body; the second chip is connected to the un-plastic-encapsulated part of the second base island through wire bonding.

6. The signal isolation transmission packaging structure according to claim 1, characterized in that: The first transceiver unit, the first chip and the first base island are connected in sequence through wire bonding; the second transceiver unit is connected to the second chip through wire bonding.

7. The signal isolation transmission packaging structure according to claim 1, characterized in that: The first chip and the first transceiver unit are arranged on the first base island in a flat manner, and / or the second chip and the second transceiver unit are arranged on the first plastic package in a flat manner.

8. The signal isolation transmission packaging structure according to claim 1, characterized in that: It also includes a second plastic package; the first plastic package, the second chip and the second transceiver unit are plastic-sealed in the second plastic package.

9. The signal isolation transmission packaging structure according to claim 1, characterized in that: The first transceiver unit is an antenna or a coil; the second transceiver unit is an antenna or a coil.

10. An isolator, characterized in that: It comprises the signal isolation transmission packaging structure as described in any one of claims 1 to 9 above.

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