Adjustable stacking packaging structure and preparation method thereof

Abstract

The present invention relates to a PCB packaging structure, and in particular to an adjustable stacking packaging structure and a preparation method thereof; the structure comprises a bottom printed board, a first laminated sheet layer, a transfer printed board, a second laminated sheet layer, a top printed board, and a metal shielding shell; a bottom pad is provided on the lower surface of the bottom printed board; the first laminated sheet layer is located on the upper surface of the bottom printed board; a plurality of first through grooves are opened in the first laminated sheet layer, and a component is arranged in each first through groove; the transfer printed board is located on the upper surface of the first laminated sheet layer; the second laminated sheet layer is located on the upper surface of the transfer printed board; a plurality of second through grooves are opened in the first laminated sheet layer, and a component is arranged in each second through groove; the top printed board is located on the upper surface of the second laminated sheet layer; and the metal shielding shell is located on the upper surface of the top printed board.

Description

Technical Field

[0001] The invention relates to a PCB packaging structure, and in particular to an adjustable stacking packaging structure and a preparation method thereof. Background Art

[0002] With the continuous development of electronic packaging products towards high density, multi-function, low power consumption and miniaturization, the system-level packaging (System in Package, SiP) using three-dimensional integration technology has achieved rapid development. The existing mature three-dimensional integration technology is mainly stacked packaging (Package on Package, PoP). POP stacked packaging can stack multiple packages together to form an overall structure, achieving a more efficient and compact package. Before assembly, the POP stacked package will perform performance tests on each component part separately, which improves the yield of the overall package and reduces the total cost; POP stacked packaging is widely used in various electronic products, but the overall structure formed by the POP stacked package has a complex spatial structure, which makes heat dissipation a problem, and thermal life becomes an important factor restricting the reliability of POP stacked packaging. In addition, due to the discreteness of component parameters and the increasing complexity of electrical performance indicators, it is sometimes necessary to replace components of the package body after the package is completed to complete the debugging of electrical performance indicators. It is difficult to debug the traditional POP stacked packaging structure after completion. Summary of the invention

[0003] To solve the above problems, the present invention provides an adjustable stacking packaging structure and a preparation method thereof, which realizes the embedding of components and the stacking of circuit boards by adopting PCB manufacturing technology, and the obtained high-density thin embedded package can also adjust and match the components of the circuit assembly.

[0004] In the first aspect, the present invention provides an adjustable stacking packaging structure, which is provided with a lower structure, a transfer printed board 5 and an upper structure in sequence from bottom to top; the lower structure includes a bottom printed board 1, and a first pressing layer 3 located on the upper surface of the bottom printed board 1; a bottom pad 2 is provided on the lower surface of the bottom printed board 1; at least one first through groove 4 is opened in the first pressing layer 3, and a component is arranged in each first through groove 4; the upper structure includes a second pressing layer 6, and a top printed board 8 located on the upper surface of the second pressing layer 6; at least one second through groove 7 is opened in the first pressing layer 3, and a component is arranged in each second through groove 7; an adjusting component and a metal shielding shell 9 are provided on the upper surface of the top printed board 8.

[0005] Furthermore, if the component is located in the first through groove 4 , the bottom of the component faces the bottom printed board 1 ; if the component is located in the second through groove 7 , the bottom of the component faces the top printed board 8 .

[0006] Furthermore, a penetrating bottom signal hole 11 is provided inside the lower structure, the lower port of the bottom signal hole 11 is connected to the bottom pad 2, and the upper port of the bottom signal hole 11 is connected to the transfer board 5; a penetrating top signal hole 12 is provided inside the upper structure, the lower port of the top signal hole 12 is connected to the transfer printed board 5, and the upper port of the top signal hole 12 is connected to the top printed board 8.

[0007] Furthermore, the first laminated sheet layer 3 and the second laminated sheet layer 6 are both formed by alternately stacking adhesive sheets and glass fiber light-distributing sheets.

[0008] Furthermore, the metal shielding shell 9 is welded and fixed on the upper surface of the top printed board 8 , and the tuning element is arranged between the metal shielding shell 9 and the top printed board 8 .

[0009] Furthermore, a completely through signal hole is provided inside the adjustable stacked packaging structure, the upper end of the completely through signal hole is connected to the top printed board 8 , and the lower end of the completely through signal hole is connected to the bottom pad 2 .

[0010] In a second aspect, based on the structure of the first aspect, the present invention further provides a method for preparing an adjustable stacked package structure, comprising the following steps:

[0011] S1. Make bottom printed boards, transfer printed boards and top printed boards;

[0012] S2. Solder components on the surface of the bottom printed circuit board and then clean the flux;

[0013] S3. A first press-fit enclosure is made according to the height of the surface components on the bottom printed board after welding, and the first press-fit enclosure is arranged around the component; the first press-fit enclosure is formed by alternately stacking bonding sheets and glass fiber cloth light boards;

[0014] S4. The upper surface of the first pressing frame is attached to the lower surface of the transfer printed circuit board and pressed;

[0015] S5. Solder components on the bottom surface of the top printed circuit board and then clean the flux;

[0016] S6. A second press-fit enclosure is made according to the height of the lower surface of the top printed circuit board after welding, and the second press-fit enclosure is arranged around the component; the second press-fit enclosure is formed by alternately stacking bonding sheets and glass fiber cloth light boards;

[0017] S7. The upper surface of the transfer printed board is attached to the lower surface of the second pressing frame and pressed;

[0018] S8. After the lamination is completed, a top signal hole, a bottom signal hole and a completely through signal hole are made on the overall structure;

[0019] S9. Install the debugging components on the top surface of the printed circuit board of the structure obtained in step S8, and then perform electrical signal testing;

[0020] S10. After the test is completed, a metal shielding cover is welded on the top surface of the top printed circuit board to complete the package, and the metal shielding cover covers all debugging components.

[0021] Beneficial effects of the present invention:

[0022] The PCB manufacturing technology is used to process the transfer printed circuit board and the pressed frame to achieve the stacking of multi-layer circuit boards and signal connectivity. After the high-density thin embedded package is realized, the circuit components can also be adjusted and replaced to ensure the best electrical performance. The thermal matching between the packaging material systems is good, the packaging structure is highly flexible, and the reliability is good, which is suitable for large-scale promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the adjustable stacking package structure of the present invention;

[0024] 1-bottom printed circuit board, 2-bottom pad, 3-first pressed sheet layer, 4-first through slot, 5-transfer printed circuit board, 6-second pressed sheet layer, 7-second through slot, 8-top printed circuit board, 9-metal shielding shell, 10a-chip component, 10b-BGA component, 10c-debugging component, 11-bottom signal hole, 12-top signal hole, 13-bottom filling glue. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] like Figure 1As shown, an adjustable stacking packaging structure of a preferred embodiment of the present invention comprises: a bottom printed board 1, a first laminated sheet 3, a transfer printed board 5, a second laminated sheet 6, a top printed board 8, and a metal shielding shell 9; a bottom pad 2 is provided on the lower surface of the bottom printed board 1; the first laminated sheet 3 is located on the upper surface of the bottom printed board 1; a plurality of first through grooves 4 are provided in the first laminated sheet 3, and a component is arranged in each first through groove 4; the transfer printed board 5 is located on the upper surface of the first laminated sheet 3; the second laminated sheet 6 is located on the upper surface of the transfer board 5; a plurality of second through grooves 7 are provided in the first laminated sheet 3, and a component is arranged in each second through groove 7; the top printed board is located on the upper surface of the second laminated sheet 6; the metal shielding shell 9 is located on the upper surface of the top printed board 8. A signal connection conductor is provided inside the transfer printed board 5.

[0027] Specifically, Figure 1 As shown, in a preferred embodiment of the present invention, two first through grooves 4 are opened in the first laminated sheet layer 3, and a chip component 10a is provided in the first through groove 4 located on the left, and the bottom of the chip component 10a faces the underlying printed circuit board 1; a BGA component 10b is provided in the first through groove 4 located on the right, and the bottom of the BGA component faces the printed circuit board 1, and a filling glue 13 is also provided at the bottom of the BGA component.

[0028] Specifically, Figure 1 As shown, in a preferred embodiment of the present invention, three second through grooves 7 are opened in the second lamination layer 6, and a chip component 10a is provided in each of the three second through grooves 7, and the bottom of the chip component 10a is facing the top printed circuit board 8, so that the upper and lower layer signals can be connected through the transfer printed circuit board.

[0029] During the manufacturing process, after the extruded and pressed sheet layers are pressed, the adhesive sheets in the pressed sheet layers will overflow and fill the through-slots, thereby achieving covering and protection of the components.

[0030] Specifically, in the preferred embodiment of the present invention, the signal interconnection between the lower structure and the upper structure is realized by setting the bottom signal hole, the top signal hole and the completely through signal hole; Figure 1As shown, a bottom layer signal hole 11 is provided in the bottom printed board 1 and the first laminated sheet 3, the bottom layer signal hole 11 has a lower port connected to the bottom pad 2, and the upper port of the bottom layer signal hole 11 is connected to the transfer printed board 5; a top layer signal hole 12 is provided in the second laminated sheet 6, the bottom port of the top layer signal hole 12 is connected to the transfer printed board 5, and the upper port of the top layer signal hole 12 is connected to the top printed board 8. A completely through signal hole is also provided inside the adjustable stacked packaging structure, the upper port of the completely through signal hole is connected to the top printed board 8, and the lower port of the completely through signal hole is connected to the bottom pad 2. In particular, the bottom layer signal hole, the top layer signal hole and the completely through signal hole need to be connected to the circuit in the printed board.

[0031] Specifically, the first laminated sheet layer 3 and the second laminated sheet layer 6 are both formed by alternately stacking adhesive sheets and glass fiber light-distributing sheets.

[0032] Specifically, a debugging component 10c is provided between the metal shielding shell 9 and the top printed board 8. The debugging component 10c is an SMD component, a chip component, a WLP component, etc. The debugging component in the present invention refers to a component mounted on the surface of the top printed board 8 that can be removed and replaced. The debugging component can be selectively replaced and adjusted according to product specifications.

[0033] The present invention also provides a method for preparing an adjustable stacked packaging structure, comprising the following steps:

[0034] S1. Making a bottom printed board, a transfer printed board and a top printed board; wherein wiring is performed in the bottom printed board, the transfer printed board and the top printed board according to the required circuit structure;

[0035] S2. Solder components on the surface of the bottom printed circuit board and then clean the flux;

[0036] S3. A first press-fit enclosure is made according to the height of the upper surface component after welding on the bottom printed board, and the first press-fit enclosure is arranged around the component; the first press-fit enclosure is formed by alternately stacking the bonding sheet and the glass fiber cloth light board; the thickness of the first press-fit enclosure is slightly higher than the height of the welded component on the bottom printed board;

[0037] S4. The upper surface of the first pressing frame is attached to the lower surface of the transfer plate and pressed together, so that the adhesive material in the first pressing frame penetrates and fills around the element;

[0038] S5. Solder components on the bottom surface of the top printed circuit board and then clean the flux;

[0039] S6. A second press-fit enclosure is made according to the height of the components on the lower surface of the top printed board after welding, and the second press-fit enclosure is arranged around the components; the second press-fit enclosure is formed by alternately stacking bonding sheets and glass fiber light cloth sheets, and the thickness of the second press-fit enclosure is slightly higher than the height of the welded components on the top printed board;

[0040] S7. The upper surface of the transfer printed board is attached to the lower surface of the second pressing frame and pressed together, so that the adhesive material in the second pressing frame penetrates and fills around the component;

[0041] S8. Make top-layer signal holes, bottom-layer signal holes and completely through-hole signal holes on the overall structure after lamination to ensure the connectivity of electrical signals between layers of circuit boards;

[0042] S9. Install the debugging components on the top surface of the printed circuit board of the structure obtained in step S8, then clean it with flux and test the electrical signal; at this time, tools can be used to adjust and replace the debugging components on the top layer to ensure that the electrical signal reaches the best;

[0043] S10. After the test is completed, a metal shield is welded to the upper surface pad of the top printed circuit board, and the metal shield covers all the debugging components to complete the package. The metal shield can be made of materials such as Kovar and has a protective function.

[0044] Specifically, steps S1-S3 and S5-S6 may be performed first, and then the top printed board, the second pressing enclosure, the transfer printed board, the first pressing enclosure and the bottom printed board are pressed together, and then S8 and subsequent steps are performed. In the present invention, unless otherwise clearly specified and limited, the terms "install", "set", "connect", "fix", "rotate" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, for ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an adjustable stacked package structure, characterized in that: The following steps are involved: S1. Manufacturing a bottom printed board, a transfer printed board and a top printed board; the transfer printed board is provided with a signal connection guide tape inside; S2. Solder components on the surface of the bottom printed circuit board and then clean the flux; S3. A first laminated sheet is made according to the height of the upper surface component after welding on the bottom printed board, and the first laminated sheet is arranged around the component; the first laminated sheet is formed by alternately stacking the bonding sheet and the glass fiber cloth light sheet; S4. The upper surface of the first laminated sheet is attached to the lower surface of the transfer printed board and laminated; S5. Solder components on the lower surface of the top printed circuit board and then clean the flux; S6. According to the height of the components on the lower surface of the top printed circuit board after welding, a second laminated sheet is made, and the second laminated sheet is arranged around the components; the second laminated sheet is formed by alternately stacking bonding sheets and glass fiber light cloth sheets; S7. The upper surface of the transfer printed board is attached to the lower surface of the second laminating sheet and pressed; S8. Making a top signal hole, a bottom signal hole and a completely through signal hole on the overall structure after the lamination is completed; The overall structure after lamination is composed of a lower structure, a transfer printed board and an upper structure from bottom to top; the lower structure includes a bottom printed board and a first lamination layer located on the upper surface of the bottom printed board; the upper structure includes a second lamination layer and a top printed board located on the upper surface of the second lamination layer; a bottom signal hole is provided inside the lower structure, the lower port of the bottom signal hole is connected to the bottom pad on the lower surface of the bottom printed board, and the upper port of the bottom signal hole is connected to the transfer printed board; a top signal hole is provided inside the upper structure, the lower port of the top signal hole is connected to the transfer printed board, and the upper port of the top signal hole is connected to the top printed board; S9. Install the debugging components on the top surface of the printed circuit board of the structure obtained in step S8, and then perform electrical signal testing; S10. After the test is completed, the metal shield is welded to the top surface of the printed circuit board to complete the package, and the metal shield covers all the debugging components; During the manufacturing process, the sheet layers are squeezed and pressed, and the adhesive sheets in the pressed sheet layers overflow and fill the through-slots, thereby achieving covering and protection of the components.

2. An adjustable stacked package structure prepared by the method for preparing an adjustable stacked package structure according to claim 1, characterized in that: The adjustable stacking packaging structure is provided with a lower structure, a transfer printed circuit board (5) and an upper structure in order from bottom to top; the lower structure includes a bottom printed circuit board (1) and a first laminated sheet (3) located on the upper surface of the bottom printed circuit board (1); a bottom solder pad (2) is provided on the lower surface of the bottom printed circuit board (1); at least one first through groove (4) is provided in the first laminated sheet (3), and a component is provided in each first through groove (4); the upper structure includes a second laminated sheet (6) and a top printed circuit board (8) located on the upper surface of the second laminated sheet (6); at least one second through groove (7) is provided in the second laminated sheet (6), and a component is provided in each second through groove (7); a metal shielding shell (9) is welded and fixed on the upper surface of the top printed circuit board (8); During the manufacturing process, after the lower structure, the transfer printed board (5) and the upper structure are pressed together, debugging components are installed on the upper surface of the top printed board (8) according to electrical performance indicators to ensure that the electrical signal reaches the best.

3. The adjustable stacked package structure according to claim 2, characterized in that: If the component is located in the first through groove (4), the bottom of the component faces the bottom printed board (1); if the component is located in the second through groove (7), the bottom of the component faces the top printed board (8).

4. The adjustable stacked package structure according to claim 2, characterized in that: A completely through signal hole is also provided inside the adjustable stacked packaging structure; the upper end of the completely through signal hole is connected to the top printed board (8), and the lower end of the completely through signal hole is connected to the bottom pad (2).

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