CN216120271U

CN216120271U - Packaging structure of radio frequency module

Info

Publication number: CN216120271U
Application number: CN202120893099.8U
Authority: CN
Inventors: 黄定海; 陈松
Original assignee: RF360 Technology Wuxi Co Ltd
Current assignee: RF360 Technology Wuxi Co Ltd
Priority date: 2021-04-28
Filing date: 2021-04-28
Publication date: 2022-03-22
Anticipated expiration: 2031-04-28

Abstract

The utility model provides a packaging structure of a radio frequency module, which can improve the production efficiency, reduce the cost, reduce the product failure generated in the stripping process and improve the yield. It includes packaging substrate, and packaging substrate's front distributes and has the pad, more than one components and parts with the pad is automatically controlled to be connected its characterized in that: the packaging structure comprises a packaging substrate, a component and a plastic package layer, wherein a gap between the component and the packaging substrate is filled with a filling medium, the outer end face of the component and the front face of the packaging substrate are coated with the shielding layer, and the plastic package layer is arranged outside the shielding layer.

Description

Packaging structure of radio frequency module

Technical Field

The utility model relates to the technical field of electromagnetic shielding, in particular to a packaging structure of a radio frequency module.

Background

With the rapid development of communication technology and the accelerated commercialization of 5G technology, the number of frequency bands required for communication terminals is also increasing dramatically, which makes electromagnetic shielding of different communication signals or frequency bands in intelligent terminals particularly important. Taking a smart phone as an example, how to make interference and shielding of signals in different frequency bands in a limited mobile phone space is a great challenge for mobile phone manufacturers. From the development trend of electromagnetic shielding inside intelligent terminals, the requirement of electromagnetic shielding hardware is already based on the prior board-level electromagnetic shielding cover, namely, components and modules welded on a circuit board are required to have an electromagnetic shielding structure.

The electromagnetic shielding method of the components or modules on the current mainstream circuit board is that after the packaging process is finished, a metal layer with the thickness of several micrometers is generated on the surface of the plastic package body by a sputtering process, so that the shielding effect is achieved. As shown in fig. 1, the following problems exist in the conventional manufacturing process of the electromagnetic shielding structure and the electromagnetic shielding mechanism: firstly, the product can be prepared into a shielding layer wrapping product after being separated into single pieces in the cutting process, and in order to prevent the problems of oxidation, pollution and the like of the shielding layer which is exposed outside, an extra protective layer needs to be additionally designed outside the metal shielding layer. In the whole process of preparing the shielding layer and the protective layer, because the processed main body is a single device, the production efficiency is extremely low, and simultaneously, because the size of a single product is small, the requirement on the precision of equipment is high, different jigs are required to be used for different product sizes, and extra cost is increased; secondly, because the adoption be that metal shielding layer wraps up the plastic envelope layer, naked metal level can produce more outward appearance inefficacys and functional failure, if when the product is peeled off, can produce the metal burr around the product, these metal burrs have the probability to drop at the pad and cause the product bridging inefficacy when the customer end welds, cause the yield to reduce.

SUMMERY OF THE UTILITY MODEL

The utility model provides a packaging structure of a radio frequency module, which can improve the production efficiency and reduce the cost, and can reduce the product failure generated during stripping and improve the yield.

The technical scheme is as follows: the utility model provides a radio frequency module's packaging structure, its includes packaging substrate, and packaging substrate's front distributes and has the pad, more than one components and parts with the pad is automatically controlled to be connected which characterized in that: the packaging structure comprises a packaging substrate, a component and a plastic package layer, wherein a gap between the component and the packaging substrate is filled with a filling medium, the outer end face of the component and the front face of the packaging substrate are coated with the shielding layer, and the plastic package layer is arranged outside the shielding layer.

It is further characterized in that: insulating layers are further arranged between the outer end faces of the components and the front faces of the packaging substrates and the shielding layers;

a connecting hole is formed in the insulating layer corresponding to the pad on the front surface of the packaging substrate, and the shielding layer is electrically connected with the packaging substrate by filling the connecting hole;

the insulating layer is a silicon oxide film, a silicon nitride film, a silicon oxynitride film or a polyimide insulating film, and the thickness of the insulating layer is 0.05-1 um;

the shielding layer adopts one metal layer or a plurality of composite metal layers of silver, copper, tin, aluminum and nickel;

the plastic packaging layer adopts an epoxy resin layer.

After the structure is adopted, the shielding layer is arranged on the outer end face of the component containing the filling medium and the front face of the packaging substrate, and the plastic packaging layer is arranged outside the shielding layer, so that the plastic packaging layer is integrally processed during preparation, the working efficiency can be improved, the cost for preparing various different jigs can be reduced, and the production cost can be reduced; meanwhile, as the shielding layer is arranged on the inner side and is not exposed, burrs are not easy to generate during stripping operation, and the failure problem is reduced.

Drawings

FIG. 1 is a process flow diagram of a prior art electromagnetic shielding layer;

FIG. 2 is a block diagram of a prior art electromagnetic shield;

FIG. 3 is a structural view of an electromagnetic shielding layer (first structure) of the present invention;

FIG. 4 is a structural view of an electromagnetic shielding layer (second structure) of the present invention;

fig. 5 is a structural view of an electromagnetic shielding layer (third structure) of the present invention;

fig. 6 to 8 are structural views of steps in the generation of a first structure of an electromagnetic shielding layer of the present invention;

fig. 9 is a process flow diagram of the electromagnetic shielding layer of the present invention;

in the figure: 10. a package substrate; 100. a pad; 20. a component; 30. welding materials; 40. a plastic packaging layer; 50. a shielding layer; 60. a protective layer; 70. filling a medium; 80. an insulating layer; 801. connecting holes; 90. and bonding wires.

Detailed Description

As shown in fig. 3, which is a schematic view of a first structure of the present invention, an encapsulation structure of a radio frequency module includes an encapsulation substrate 10, where the encapsulation substrate 10 may be made by a PCB (printed circuit board) technology, that is, a two-layer or multi-layer circuit board using a core board, a prepreg, and a copper layer as materials, or a derivative novel encapsulation substrate. The front surface of the package substrate 10 is distributed with pads 100, and more than one component 20 is soldered on the pads 100 through a soldering material 30, so as to realize the electric control connection of the component 20 and the package substrate 10, wherein the soldering material 30 can select a solder ball, a copper column or a tin-containing alloy with a certain height. The component 20 may alternatively be a semiconductor chip, a single function component or a multi-function integrated component suitable for Surface Mount Technology (SMT) and Flip Chip (FC). Specifically, the components 20 include, but are not limited to, filters, low noise amplifier chips, power amplifier chips, duplexers, radio frequency switches, integrated passive components (IPDs), and the like. The integrated passive element replaces the traditional capacitor, inductor and resistor, and the number of elements in the radio frequency module is reduced.

The gap between the component 20 and the package substrate 10 is filled with a filling medium 70, which serves to electrically insulate and support the component 20. The filling medium 70 may be selected from an underfill (underfill) or a chemical glue with epoxy as the main material.

The outer end face of the component 20 and the front face of the package substrate 10 are coated with a shielding layer 50, and the shielding function is realized by the shielding layer 50. This shielding layer 50 adopts a metal level or multiple composite metal level in silver, copper, tin, aluminium, nickel, wherein if chooseing for use copper as the shielding layer, 1um ~3um thickness can satisfy the application demand of 4G 5G radio frequency module. The exterior of the shielding layer 50 is further provided with a plastic package layer 40, and the plastic package layer 40 is made of an epoxy resin material.

Fig. 4 is a schematic structural diagram of a second structure of the present invention, which is different from the first structure in that an insulation layer 80 is additionally disposed between the outer end face of the component 20 and the front face of the package substrate 10 and the shielding layer 50, and the insulation layer 80 is used for electrically insulating the shielding layer 50 from the component 20 and the package substrate 10. The insulating layer 80 is made of a silicon oxide film, a silicon nitride film, a silicon oxynitride film or a polyimide insulating film, and has a thickness of 0.05-1 um. In order to realize the electrical connection between the shielding layer 50 and the package substrate 10, a connection hole 801 is further formed in the insulating layer 80, the shielding layer 50 is electrically connected to the package substrate 10 by filling the connection hole 801, and the package substrate 10 can be grounded.

Fig. 5 is a schematic structural diagram of a third structure of the present invention, which is different from the first structure in that the component 20 is electrically connected to the package substrate 10 by wire bonding. The back surface of the component 20 is fixed on the package substrate 10 by a die attach adhesive or a die attach film, and the bonding wire 90 connects the pad of the component 20 and the pad 100 of the package substrate 10 by a wire bonding technique. The component 20 and the bond wires are encapsulated by an underfill medium 70 for isolation.

A method for manufacturing a package structure of a radio frequency module, as shown in FIG. 6, a component 20 is soldered on a pad 100 of a package substrate 10 by SMT (surface mount technology) or FC flip chip assembly,

step one, as shown in fig. 7, a glue filling or coating method is adopted to place a glue filling point of a filling medium 70 at a gap between the component 20 and the package substrate 10, the filling medium 70 fills the gap through capillary action, and the curing and forming are performed;

step two, as shown in fig. 8, preparing a shielding layer 50 on the outer end face of the component 10 and the front face of the package substrate 10 by physical vapor deposition, sputtering or electroplating;

and step three, preparing the plastic packaging layer 40 outside the shielding layer 50 by using an injection molding mode, forming a structural diagram shown in fig. 3, and then cutting, testing and packaging.

Further, in order to ensure that the shielding layer 50 is electrically insulated from the component 20 and the package substrate 10 before the second step. An insulating layer 80 is first prepared on the outer end surface of the component 20 and the front surface of the package substrate 10 by chemical vapor deposition.

According to the utility model, the shielding layer 50 is arranged inside, namely the outer end face of the component 10 and the front face of the packaging substrate 10, and the plastic packaging layer 40 is arranged outside the shielding layer 50, so that the shielding layer 40 is arranged inside and not exposed, burrs are not easy to generate during stripping operation, and the failure problem can be effectively reduced.

Meanwhile, according to the manufacturing method, the cutting process is arranged after the plastic packaging process, and the processes before cutting are all directed at the combination of the plurality of components 20 and the packaging substrate 10, so that the operation is convenient, the working efficiency can be effectively improved, the cost for preparing various jigs can be reduced, and the production cost can be reduced.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a radio frequency module's packaging structure, its includes packaging substrate, and packaging substrate's front distributes and has the pad, more than one components and parts with the pad is automatically controlled to be connected which characterized in that: the packaging structure comprises a packaging substrate, a component and a plastic package layer, wherein a gap between the component and the packaging substrate is filled with a filling medium, the outer end face of the component and the front face of the packaging substrate are coated with the shielding layer, and the plastic package layer is arranged outside the shielding layer.

2. The packaging structure of claim 1, wherein: and insulating layers are further arranged between the outer end faces of the components and the front faces of the packaging substrates and the shielding layers.

3. The packaging structure of claim 2, wherein: and the insulating layer is also provided with a connecting hole corresponding to the pad on the front surface of the packaging substrate, and the shielding layer is electrically connected with the packaging substrate by filling the connecting hole.

4. The packaging structure of claim 3, wherein: the insulating layer adopts silicon oxide film, silicon nitride film, silicon oxynitride film or polyimide insulating film, and thickness is between 0.05~1 um.

5. The packaging structure of claim 4, wherein: the plastic packaging layer adopts an epoxy resin layer.