CN106340498B - A kind of encapsulating structure and its manufacturing method with electromagnetic shielding grounding function - Google Patents

Abstract

The present invention relates to a kind of encapsulating structures and its manufacturing method with electromagnetic shielding grounding function, and the structure includes substrate（1）, the substrate（1）Front is pasted with plank（2）, the plank（2）Including sticky glue-line（2.1）, nonconductive dielectric layer（2.2）And copper foil layer（2.3）, the copper foil layer（2.3）With substrate（1）Ground path（1.1）It is connected, the plank（2）On be provided with trepanning（3）, the trepanning（3）Top is provided with chip（4）, the chip（4）The back side passes through multiple solder bumps（5）With substrate（1）It is connected, the chip（4）Periphery is encapsulated with plastic packaging material（6）, the substrate（1）Side, plank（2）Side and plastic packaging material（6）Outer surface is coated with shielding metal leve（7）.The present invention can solve the problems, such as that earthing effect is bad in the prior art, can improve production efficiency, simplify technique, play good effectiveness.

Description

A packaging structure with electromagnetic shielding and grounding function and its manufacturing method

technical field

The invention relates to a packaging structure with electromagnetic shielding and grounding functions and a manufacturing method thereof, belonging to the technical field of semiconductor packaging.

Background technique

Since the RF package structure is susceptible to external electromagnetic interference, when it is mounted on a circuit board, special attention should be paid to mutual interference to avoid abnormal operation. In order to achieve the shielding effect, a shielding component is arranged above the chip, and the shielding component is grounded, so that the chip can be shielded from external electromagnetic interference. There are many ways to ground the shielding component. As shown in FIG. 1, a plurality of grounding conductors 40 are arranged above the substrate, and the shielding layer 70 is in contact with the grounding conductor 40, and grounded to perform electromagnetic shielding. In this structure The grounding conductors are placed on the substrate one by one, and the working time is long, and the grounding conductors are made of solder paste or conductive adhesive, which are formed after reflow soldering or heating and curing. There may be differences in the height of the formation, which may result in no cutting when cutting. To the corresponding position, this will cause poor contact between the shielding layer and the grounding conductor, and the shielding layer cannot be grounded, which of course affects the shielding function.

Contents of the invention

The technical problem to be solved by the present invention is to provide a packaging structure with electromagnetic shielding and grounding function and its manufacturing method for the above-mentioned prior art, which can solve the problem of poor grounding effect in the prior art, improve production efficiency, simplify the process, Play a very good electromagnetic shielding effect.

The technical solution adopted by the present invention to solve the above problems is: a packaging structure with electromagnetic shielding and grounding functions, which includes a substrate, the substrate includes a grounding line, and a plate is mounted on the front of the substrate, and the plate includes a top-to-bottom A viscous adhesive layer, a non-conductive medium layer, and a copper foil layer are arranged in sequence, the copper foil layer is connected to the grounding line, an opening is provided on the board, a chip is erected above the opening, and the front side of the chip is Connected to the substrate through a plurality of solder bumps, the periphery of the chip is encapsulated with a plastic encapsulant, the side of the substrate, the side of the plate and the outer surface of the plastic encapsulant are covered with a shielding metal layer, the shielding metal layer and the copper foil layer connected sideways.

The opening is filled with plastic sealing compound.

A method for manufacturing a packaging structure with an electromagnetic shielding and grounding function, the method comprising the following steps:

Step 1. Take a board. The board has three layers. The first layer is viscous glue, the middle layer is non-conductive medium, and the bottom layer is copper foil;

Step 2. Opening the plate in step 1;

Step 3. Mount the chip upside down on the hole, the edge of the back of the chip is attached to the edge of the upper surface of the hole, and there are solder bumps on the back of the chip;

Step 4, attaching the entire plate to the substrate, and electrically connecting the solder bumps to the substrate through a reflow process, and electrically connecting the grounding circuit on the substrate to the copper foil of the plate to form a grounding structure;

Step 5, encapsulating the periphery of the chip with a plastic encapsulant;

Step 6. Cutting the encapsulated semi-finished product into single units;

Step 7. Cover the surface of the cut single unit with a shielding metal layer.

The four corners and edge areas of the board in step 1 have positioning mark points for identification.

The positioning mark points are square, cross or trapezoidal.

The opening processing method is a laser method, a mechanical punching method or an etching method.

The size of the hole is smaller than the size of the target chip.

The holes are arranged in a matrix.

The bonding method of the plate and the substrate is a conductive adhesive bonding method, a solder connection method or a mechanical clip connection method.

The method of covering the shielding metal layer is chemical vapor deposition, chemical electroplating, electrolytic electroplating, spraying, printing or sputtering.

Compared with the prior art, the present invention has the advantages of:

1. The copper foil used for grounding is bonded by the viscous material between the plastic sealant and the substrate, which avoids the possibility of peeling off the grounding copper block due to cutting stress during cutting, and reduces the problem of poor shielding effect caused by poor grounding;

2. Adopt the method of mounting the chip first, then mounting the whole piece of copper foil, and then reflowing the whole to improve efficiency and reduce production costs;

3. The present invention is also easy to implement the cavity at the bottom of the chip and the filling method at the bottom of the chip, wherein the cavity at the bottom of the chip can be used for the packaging of a surface acoustic wave sensor;

4. The whole sheet and the whole substrate are laminated, which can simplify the process and save materials and time;

5. The grounding conductor does not need to be set up individually, but can be formed as a whole to improve efficiency and increase product reliability.

Description of drawings

FIG. 1 is a schematic diagram of a conventional grounding method of a shielding component.

FIG. 2 is a schematic diagram of a packaging structure with electromagnetic shielding and grounding functions according to the present invention.

FIG. 3 is a schematic diagram of another embodiment of a packaging structure with an electromagnetic shielding and grounding function according to the present invention.

4 to 10 are process flow charts of a manufacturing method of a packaging structure with an electromagnetic shielding and grounding function according to the present invention.

Fig. 11 and Fig. 12 are schematic diagrams of the design of the grounding circuit of each unit on the substrate of a package structure with electromagnetic shielding and grounding function according to the present invention.

in:

Substrate 1

Ground Line 1.1

Plate 2

Adhesive adhesive layer 2.1

Non-conductive dielectric layer 2.2

Copper foil layer 2.3

Hole 3

chip 4

Solder bump 5

Plastic compound 6

shielding metal layer 7

Ground line 8.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 2, a packaging structure with electromagnetic shielding and grounding functions in this embodiment includes a substrate 1, the substrate 1 includes a grounding circuit 1.1, and a plate 2 is mounted on the front of the substrate 1, and the plate 2 includes a viscous adhesive layer 2.1, a non-conductive medium layer 2.2 and a copper foil layer 2.3 arranged in sequence from top to bottom, the copper foil layer 2.3 is connected to the grounding line 1.1, and the board 2 is provided with an opening 3, so A chip 4 is erected above the opening 3, the back of the chip 4 is connected to the substrate 1 through a plurality of solder bumps 5, the periphery of the chip 4 is encapsulated with a plastic encapsulant 6, the sides of the substrate 1 and the plate 2 and the plastic seal The outer surface of the material 6 is coated with a shielding metal layer 7, and the shielding metal layer 7 is connected to the side of the copper foil layer 2.3.

As shown in FIG. 3 , the opening 3 in this embodiment is filled with a molding compound 6 .

Its production method is as follows:

Step 1, see Figure 4, take a special plate, which has three layers, the first layer is viscous glue, the middle layer is non-conductive medium (with certain elasticity), and the bottom layer is copper foil; The four corners and the edge area have positioning mark points for identification, which can be in the shape of square, cross or trapezoid;

Step 2. Referring to Figure 5, the plate in step 1 is processed by opening holes. The processing method can be laser method, mechanical punching method or etching method, and the size of the hole is smaller than the chip size;

The holes are arranged in a matrix;

Step 3, see Figure 6, mount the chip upside down on the opening, the edge of the back of the chip is attached to the edge of the hole, and there are solder bumps on the back of the chip;

Step 4. Referring to FIG. 7 , attach the entire sheet to the substrate, electrically connect the solder bumps to the substrate through a reflow process, and electrically connect the grounding line on the substrate to the copper foil of the sheet to form a grounding structure;

The design of the grounding line on the substrate can be a continuous ring structure around a single product line, see Figure 11; or a scattered shape around a single product line, which can be rectangular, circular, elliptical or irregular, and the quantity Can be single or multiple, see Figure 12;

Step 5, see Figure 8, encapsulate the periphery of the chip with plastic encapsulant;

If the bottom of the chip needs to be filled, grooves need to be made on the board to facilitate the flow of the molding compound; if the bottom of the chip needs to maintain a cavity structure, there is no need to make grooves on the board;

Step 6, see Figure 9, cut the encapsulated semi-finished product into a single unit, with the plate exposed on the side;

Step 7. Referring to Figure 10, cover the surface of the single unit after cutting with a shielding metal layer. The shielding metal layer can be gold, silver, copper, nickel, chromium, tin, aluminum, etc. or a combination of multiple metal materials. The grounding is realized through the grounding line on the side of the plate and the substrate, and the covering method can be chemical vapor deposition, chemical electroplating, electrolytic plating, spraying, printing or sputtering.

In addition to the above-mentioned embodiments, the present invention also includes other implementations, and any technical solution formed by equivalent transformation or equivalent replacement shall fall within the protection scope of the claims of the present invention.

Claims (10)

1. a kind of encapsulating structure with electromagnetic shielding grounding function, it is characterised in that：It includes substrate（1）, the substrate（1） Including ground path（1.1）, the substrate（1）Front is pasted with plank（2）, the plank（2）Including cloth successively from top to bottom The sticky glue-line set（2.1）, nonconductive dielectric layer（2.2）And copper foil layer（2.3）, the copper foil layer（2.3）With ground path （1.1）It is connected, the plank（2）On be provided with trepanning（3）, the trepanning（3）Top is provided with chip（4）, the chip （4）The back side passes through multiple solder bumps（5）With substrate（1）It is connected, the chip（4）Periphery is encapsulated with plastic packaging material（6）, described Substrate（1）Side, plank（2）Side and plastic packaging material（6）Outer surface is coated with shielding metal leve（7）, the shielding metal Layer（7）With copper foil layer（2.3）Side is connected.

2. a kind of encapsulating structure with electromagnetic shielding grounding function according to claim 1, it is characterised in that：It is described to open Hole（3）It is interior to be filled with plastic packaging material（6）.

3. a kind of manufacturing method with the encapsulating structure for being electromagnetically shielded grounding function, it is characterised in that the method includes following Step：

Step 1: taking a plank, the plank shares three layers, and first layer is sticky glue, and intermediate one layer is non-conductive medium, most lower One layer of face is copper foil；

Step 2: the plank in step 1 is done trepanning processing；

Step 3: chip upside down is mounted on tapping, chip back edge is bonded with bore edges, and chip back, which has, to be made Solder bump；

Step 4: full wafer plank is bonded with substrate, and solder bump is set to be connect with electrical property of substrate by reflow soldering process, and base The copper foil of ground path and plank on plate is electrically connected, and ground structure is formed；

Step 5: chip periphery carries out plastic packaging material encapsulating；

Step 6: the semi-finished product after encapsulating are cut into single unit；

Step 7: single cell surface after cutting is covered shielding metal leve.

4. a kind of manufacturing method with the encapsulating structure for being electromagnetically shielded grounding function according to claim 3, feature It is：Four angles of the plank in step 1 and fringe region are useful for the telltale mark point of identification.

5. a kind of manufacturing method with the encapsulating structure for being electromagnetically shielded grounding function according to claim 4, feature It is：The telltale mark point is rectangular, cross or trapezoidal.

6. a kind of manufacturing method with the encapsulating structure for being electromagnetically shielded grounding function according to claim 3, feature It is：The trepanning processing mode is radium-shine mode, mechanical punching mode or etching mode.

7. a kind of manufacturing method with the encapsulating structure for being electromagnetically shielded grounding function according to claim 3, feature It is：The size in the hole need to be less than objective chip size.

8. a kind of manufacturing method with the encapsulating structure for being electromagnetically shielded grounding function according to claim 3, feature It is：The hole is arranged in matrix-style.

9. a kind of manufacturing method with the encapsulating structure for being electromagnetically shielded grounding function according to claim 3, feature It is：The mode that the plank is bonded with substrate is that conducting resinl binds mode, solder connection mode or mechanical snap connection type.

10. a kind of manufacturing method with the encapsulating structure for being electromagnetically shielded grounding function according to claim 3, feature It is：The coverage mode is the process of chemical vapor deposition, electroless plating, electrolysis plating, spraying, printing or sputter.