TWI728318B - System in package structure - Google Patents

Abstract

The present invention relates to a system in package structure having at least one function chip and multiple electronic components mounted on a lead frame. The connecting pads of the electronic components are attached to the lead frame through the solder pastes. A barrier unit is formed on the lead frame and located beside the connecting pads of the electronic components. When the system-level package structure is packaged and subjected to temperature rise in the subsequent process and the internal solder pastes are melted, the melted solder pastes are blocked by the barrier unit to keep the melted solder pastes from leaking out of the package. Thereby the integrity of the system-in-package structure is maintained.

Description

System-in-package structure

The present invention relates to a packaging structure, in particular to a system-in-a-package structure.

The system-in-package is to integrate multiple chips and electronic components into a single package structure, so that the single package structure can provide a system function to meet the current demand for high-performance components. As shown in FIG. 6, in the prior art system-in-package structure 50, for electronic components 51 (such as inductors) with a relatively large internal volume, a relatively large amount of internal solder paste 54 is required between the connection pad 52 and the lead frame 53. Only by the reflow process can the relatively large electronic components 51 be fixed.

When the prior art system-in-package structure 50 is to be placed on the corresponding circuit structure, it is necessary to apply external solder paste on the exposed contact point 55 of the lead frame 53 and then perform the reflow process. During the reflow process, The external solder paste is melted by controlling the heating to achieve the bonding effect. However, during the reflow process, heating not only causes the external solder paste to melt, but also causes the internal solder paste 54 to melt. Due to the large amount of the internal solder paste 54, it is easy to overflow from between the packaging material 56 and the lead frame 53 after melting, resulting in the failure of the prior art system-in-package structure 50.

In view of this, the present invention improves the prior art system-in-package structure to prevent the internal solder paste from overflowing out of the packaging material during the subsequent reflow process.

In order to achieve the above-mentioned object of the invention, the present invention provides a system-in-package structure, which includes: at least one functional chip and a plurality of electronic components, each electronic component includes a body and a plurality of connection pads, the connection pads are arranged on the body Bottom side; a lead frame, the functional chip and electronic components are arranged on the first surface of the lead frame and form an electrical connection with the lead frame, and the connection pads of the electronic components are arranged on the first of the lead frame through solder paste The second surface of the lead frame is provided with a plurality of external contacts, the first surface of the lead frame is provided with at least one blocking unit, and each blocking unit includes at least one sub-blocking unit. The sub-blocking unit surrounds at least one of the connection pads of the corresponding electronic component, so as to surround the connection pad therein; and a packaging material which covers the functional chip, the electronic component, and the first part of the lead frame On the surface.

The advantage of the present invention is that when the packaged system-in-package structure encounters an increase in temperature during the subsequent reflow process, which causes the internal solder paste to melt, the arrangement of the barrier unit prevents the molten solder paste from overflowing the packaging material. In addition, in order to maintain the integrity of the system-in-package structure, thereby avoiding its failure.

10: System-in-package structure

20: Electronic components

21: body

22: Connection pad

23: Solder paste

30: Lead frame

31, 31A, 31B: barrier unit

311, 311A, 311B: Sub-blocking unit

32: External contact

40: Packaging material

50: System-in-package structure

51: electronic components

52: connection pad

53: Lead frame

54: Internal solder paste

55: Contact

56: Packaging material

FIG. 1 is a schematic side sectional view of a part of the structure of the first embodiment of the present invention.

Fig. 2 is a top view of a part of the structure of the lead frame of the first embodiment of the present invention.

3 is a top view of a part of the structure of the lead frame of the second embodiment of the present invention.

4 is a schematic side sectional view of part of the structure of the third embodiment of the present invention.

Fig. 5 is a top view of a part of the structure of the lead frame of the third embodiment of the present invention.

Fig. 6 is a schematic side sectional view of a part of the structure of the prior art.

The following figures and embodiments of the present invention are used to further explain the technical means adopted by the present invention to achieve the intended purpose of the invention. The figures are simplified for illustrative purposes only and describe the relationship between the elements and components of the present invention. To illustrate the structure or method of the present invention, therefore, the elements shown in the figure are not presented in actual numbers, actual shapes, actual sizes, and actual ratios. The sizes or size ratios have been enlarged or simplified to provide a better description. , The actual number, actual shape or actual size ratio has been selectively designed and configured, and the detailed component layout may be more complicated.

Please refer to FIG. 1, the system-in-package structure 10 of the present invention includes at least one functional chip (not shown in the figure), a plurality of electronic components 20, a lead frame 30, and a packaging material 40.

The aforementioned functional chip and electronic component 20 are arranged on the first surface of the lead frame 30 and are electrically connected to the lead frame 30. Each electronic component 20 includes a body 21 and a plurality of connection pads 22. The connection pads 22 are arranged on the body 21 The bottom side. The connection pad 22 of each electronic component 20 is disposed on the first surface of the lead frame 30 through the solder paste 23 and forms an electrical connection with the lead frame 30. Generally speaking, the functional chips and electronic components 20 can be configured according to the functions to be provided by the system-in-package structure 10, such as digital processing chips, memory chips, antennas, passive components, etc., but not limited thereto.

The first surface of the aforementioned lead frame 30 is provided with at least one blocking unit 31, each blocking unit 31 is disposed on the side of the connection pad 22 of one of the electronic components 20, and the second surface of the lead frame 30 is provided with a number of external contacts 32, Used to form an electrical connection with an external circuit. The aforementioned packaging material 40 covers the first surface of the functional chip, the electronic component 20, and the lead frame 30 to protect the first surface of the functional chip, the electronic component 20 and the lead frame 30 from external attack. damage.

Therefore, when the system-in-package structure 10 of the present invention is disposed on the corresponding circuit structure, when the external solder paste is applied to the external contact 32 of the lead frame 30 and then the reflow process is performed, if the temperature is increased, the system-in-package The solder paste 23 in the structure 10 melts, and the overflowing solder paste 23 is blocked by the barrier unit 31 Prevent from overflowing between the lead frame 30 and the packaging material 40, so as to maintain the integrity of the system-in-package structure 10 and prevent its failure.

In one embodiment (as shown in FIG. 2), each blocking unit 31 includes a plurality of sub-blocking units 311, and each sub-blocking unit 311 is arranged at intervals around one of the connection pads 22 of the corresponding electronic component 20 to The connection pad 22 is surrounded therein, and when the solder paste 23 corresponding to the connection pad 22 melts and overflows, it will be blocked by the sub-blocking unit 311 to prevent further overflowing out of the packaging material 40. In another embodiment (as shown in FIG. 3), each blocking unit 31A includes a sub-blocking unit 311A, and the sub-blocking unit 311A is continuously enclosed around one of the connection pads 22 of the corresponding electronic component 20, In order to surround the connection pad 22 therein, when the solder paste 23 corresponding to the connection pad 22 melts and overflows, it will be blocked by the sub-blocking unit 311A to prevent further overflow of the packaging material 40. The arrangement of the barrier units is not limited to the foregoing embodiments. Each barrier unit can also be arranged around the corresponding electronic component at intervals or in a continuous closed shape to surround the connection pads of the electronic component. It can also achieve the effect of preventing the molten solder paste from overflowing outside the packaging material 40.

Furthermore, in one embodiment (as shown in FIGS. 1 and 2), each sub-blocking unit 311 of each blocking unit 31 is recessed on the surface of the lead frame 30, and when the solder paste 23 melts and overflows, It will flow into the concave sub-blocking unit 311 first and be collected therein to prevent further overflowing out of the packaging material 40. In another embodiment (as shown in FIGS. 4 and 5), each sub-blocking unit 311B of each blocking unit 31B is protrudingly arranged on the surface of the lead frame 30B, and when the solder paste 23 melts and overflows, it will be sub-blocked. The resistance of the unit 311B prevents further overflow of the packaging material 40.

The above are only the embodiments of the present invention, and do not limit the present invention in any form. Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the relevant technical field, Without departing from the scope of the technical solution of the present invention, when the technical content disclosed above can be used to make slight changes or modification into equivalent embodiments with equivalent changes, but generally Without departing from the content of the technical solution of the present invention, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

10: System-in-package structure

20: Electronic components

21: body

22: Connection pad

23: Solder paste

30: Lead frame

31: Barrier unit

311: Sub-blocking unit

32: External contact

40: Packaging material

Claims (9)

A system-in-package structure includes: at least one functional chip and a plurality of electronic components, each electronic component includes a body and a plurality of connection pads, the connection pads are arranged on the bottom side of the body; a lead frame, the functional chip And the electronic component is arranged on the first surface of the lead frame and forms an electrical connection with the lead frame, the connection pad of the electronic component is arranged on the first surface of the lead frame through the solder paste to form an electrical connection with the lead frame, the lead frame The second surface is provided with a plurality of external contacts, the first surface of the lead frame is provided with at least one barrier unit, and each barrier unit includes at least one sub-barrier unit, and the sub-barrier unit surrounds at least one of the corresponding electronic components. Around one of the connection pads to surround the connection pad; and a packaging material covering the first surface of the functional chip, the electronic component, and the lead frame. The system-in-package structure according to claim 1, wherein the blocking unit is recessed on the first surface of the lead frame. The system-in-package structure according to claim 1, wherein the blocking unit is protrudingly arranged on the first surface of the lead frame. The system-in-package structure according to claim 1, wherein each barrier unit includes a plurality of sub-barrier units, and each sub-barrier unit is arranged at intervals around one of the connection pads of the corresponding electronic component to surround the connection pad. . The system-in-package structure according to claim 1, wherein each barrier unit includes a sub-barrier unit that surrounds the corresponding electronic component in a continuous closed shape to surround each connection pad of the electronic component In it. The system-in-package structure according to claim 1, wherein each barrier unit includes a sub-barrier unit that surrounds one of the connection pads of the corresponding electronic component in a continuous closed shape, so that the connection pad Surrounded by it. The system-in-package structure according to claim 1, wherein each barrier unit includes a plurality of sub-barrier units, and each sub-barrier unit is arranged at intervals around the corresponding electronic component to surround each connection pad of the electronic component. The system-in-package structure according to any one of claims 3 to 7, wherein the sub-blocking unit is recessedly arranged on the first surface of the lead frame. The system-in-package structure according to any one of claims 3 to 7, wherein the sub-blocking unit is protrudingly arranged on the first surface of the lead frame.

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