WO2024027571A1

WO2024027571A1 - Package method for radio-frequency module, and radio-frequency module

Info

Publication number: WO2024027571A1
Application number: PCT/CN2023/109737
Authority: WO
Inventors: 胡锦钊; 陈云; 罗伟侠; 李帅; 杨睿智; 张磊; 郭嘉帅
Original assignee: 深圳飞骧科技股份有限公司
Priority date: 2022-08-05
Filing date: 2023-07-28
Publication date: 2024-02-08
Also published as: CN115000654A; CN115000654B

Abstract

Provided are a package method for a radio-frequency module, and a radio-frequency module, which are applicable to the field of die packaging. The method comprises: performing front-end manufacturing on a substrate; pre-assembling, on the surface of the substrate, a radio-frequency die device that includes a filter, and determining the fixed position of the radio-frequency die device; performing primary SMT treatment on the substrate; performing organic adhesive film coating treatment on the surface of the substrate; performing laser film melting according to the position of an organic adhesive film required by a passive element, so as to form an exposed contact; performing secondary SMT treatment on the surface of the organic adhesive film; and performing plastic packaging on the substrate and the radio-frequency die device, and performing cutting and packaging to obtain a radio-frequency module. Thus, on the basis of original BDMP, the packaging of passive capacitor and inductor components can be realized.

Description

A kind of packaging method of radio frequency module and radio frequency module

Technical field

The invention belongs to the field of chip packaging, and in particular relates to a packaging method of a radio frequency module and a radio frequency module.

Background technique

A radio frequency module is a radio frequency chip that contains one or several radio frequency components. These radio frequency components include filters, low noise amplifiers, radio frequency switches, amplifiers, etc. These radio frequency components are passed through the substrate and a certain radio frequency microprocessor. The RF module chip can be formed by connecting the strips and packaging them. Today's radio frequency modules are becoming more and more highly integrated and low-cost. Therefore, bare chip module packaging (Bare Die Module Package, referred to as BDMP), which does not require filters to be packaged in advance, has been developed and applied. In this packaging technology, the unpackaged bare filter chip is ball-mounted and directly mounted on the substrate together with switches and other devices. After that, a layer of organic adhesive film (such as Toray Semiconductor Adhesive, which is tens of microns thick) is placed on the substrate. (TSA for short) is sealed on the entire module as a substrate protective layer to protect the filter's finger structure to form a cavity. Finally, the entire chip is packaged through plastic sealing.

In the traditional BDMP packaging process, the process of reflow soldering and heating and curing of the organic adhesive film is prone to softening and short-circuiting of closely spaced solder balls; or some components are smaller, resulting in a reduction in the quality of the organic adhesive film. Both situations limit the selection of components in the BDMP package, that is, the passive capacitor and inductor components often used in traditional modules cannot appear, which greatly increases the difficulty and cost of debugging the BDMP module. At present, BDMP can generally only be used on receiving modules with relatively low matching difficulty, which limits the application scenarios of this low-cost packaging form.

Contents of the invention

Embodiments of the present invention provide a radio frequency module packaging method and radio frequency module, aiming to solve the problem that the existing BDMP packaging is not compatible with the packaging of passive capacitance and inductance components due to problems such as heating and curing of organic adhesive films.

In a first aspect, an embodiment of the present invention provides a packaging method for a radio frequency module. The method includes the following steps:

Front-end manufacturing of substrates;

Pre-assemble the radio frequency chip device including the filter on the surface of the substrate, and determine the fixed position of the radio frequency chip device;

Perform the first SMT patch processing on the substrate;

Carry out organic glue film coating treatment on the surface of the substrate;

Perform laser melting according to the position of the organic film required for passive components to form exposed contacts;

Perform a second SMT patch treatment on the surface of the organic adhesive film;

The substrate and the radio frequency chip device are plastic-sealed, and the radio frequency module is obtained by cutting and packaging.

Furthermore, in the step of pre-assembling the radio frequency chip device including the filter on the surface of the substrate and determining the fixed position of the radio frequency chip, the pre-assembly is used to align the substrate and the The radio frequency chip is used for ball implantation.

Furthermore, in the step of performing the first SMT patching process on the substrate, the first SMT patching process is used to place the radio frequency chip device and the substrate at the fixed position. welding.

Furthermore, in the step of performing a second SMT patch treatment on the surface of the organic adhesive film, the second SMT patch treatment is used to connect the passive component and the substrate at the exposed contact point. Weld on.

Furthermore, the step of plastic-sealing the substrate and the radio frequency chip device, and obtaining the radio frequency module through cutting and packaging includes the following sub-steps:

Perform laser printing on the substrate and use resin for plastic sealing;

Cut the substrate to obtain a radio frequency module;

Electromagnetic shielding is performed on the radio frequency module, and the packaging is completed.

In a second aspect, embodiments of the present invention also provide a radio frequency module obtained by the packaging method of a radio frequency module as described in any one of the above embodiments, including:

A substrate, which is divided into a contact layer with contacts and a solder ball layer with multiple solder balls;

A radio frequency chip device, the radio frequency chip device includes an exposed filter and a plurality of chip solder balls on the same side as the filter, and the chip solder balls form an electrical connection with the contact;

a plurality of passive components, the passive components forming electrical connections with the contacts;

A substrate protective layer covering the substrate and the radio frequency chip device, and forming an opening where the passive component meets the contact;

A solid resin layer covering the substrate protective layer and the passive component;

The radio frequency module is made by the packaging method of the radio frequency module described in any one of the above embodiments.

Furthermore, the substrate protective layer is an organic glue film.

Furthermore, the radio frequency chip device is electrically connected to the contact point of the substrate through the chip solder ball, and a filter cavity is formed through the organic glue film.

Furthermore, the exposed surface of the filter on the radio frequency chip is on a side of the radio frequency chip device facing the filter cavity.

The beneficial effects achieved by the present invention are due to the use of a packaging process of adding laser coating and SMT surface patching after the organic film coating, making it possible to realize passive capacitance and inductance components based on the original BDMP packaging. packaging, and avoid the problems of solder ball softening, short circuit and low film quality caused by reflow soldering and heating and curing of organic adhesive films.

Description of drawings

Figure 1 is a block flow diagram of the steps of a radio frequency module packaging method provided by an embodiment of the present invention;

Figure 2 is a schematic diagram of laser film melting provided by an embodiment of the present invention;

Figure 3 is a schematic structural diagram of a radio frequency module provided by an embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention.

Please refer to Figure 1. Figure 1 is a block flow diagram of a packaging method for a radio frequency module provided by an embodiment of the present invention. The method specifically includes the following steps:

S1. Perform front-end manufacturing of the substrate.

Generally, the substrate is a high-purity silicon wafer. In the chip manufacturing process, front-end manufacturing mainly refers to the wafer processing process and the wafer probing process. These two processes are to process the wafer into a Each individual die is placed separately according to its characteristics to facilitate assembly of the die.

S2. Pre-assemble the radio frequency chip device including the filter on the surface of the substrate, and determine the fixed position of the radio frequency chip device.

Furthermore, in step S2, the pre-assembly is used to ball-mount the substrate and the radio frequency chip device. Ball mounting refers to the process of adding solder to the chip pad in the chip process. In the embodiment of the present invention, the ball mounting on the substrate is for its use as a module, and the ball mounting of the radio frequency chip device This is to allow it to have a structure that is welded to the contacts of the substrate. The substrate is a general circuit board with contacts on its bright side. However, when being assembled with other electronic components, one side of it retains its original appearance. The other side needs to be soldered at the corresponding position of the contact.

S3. Perform the first SMT patch processing on the substrate.

SMT (Surface Mounted Technology) is the abbreviation of a series of process processes that are processed on the basis of substrates. Specifically, leadless or short-lead surface mount components (SMC/SMD) are installed on printed circuits. On the surface of the board or the surface of other substrates, they are welded and assembled by reflow or dip soldering.

Furthermore, in step S3, the first SMT patch processing is used to weld the radio frequency chip device and the substrate at the fixed position.

S4. Perform an organic glue film coating process on the surface of the substrate.

As a substrate protective layer, the organic adhesive film mainly protects the surface of the substrate and the bare chip in a physical partition manner to prevent them from being damaged in other links and during use.

S5. Perform laser melting according to the position of the organic film required for the passive component to form exposed contacts.

For example, please refer to Figure 2. Figure 2 is a schematic diagram of laser film melting provided by an embodiment of the present invention. Passive components are a type of electronic components because they do not have any form of power supply inside and respond passively to electrical signals. , such as capacitors, resistors, inductors, etc. In the embodiment of the present invention, the passive components need to be installed in positions other than the radio frequency chip. However, because the entire surface of the substrate has been covered with an organic adhesive film in step S4, for The contacts for welding the passive components have been covered by the organic adhesive film, so in this step, a laser is used to melt the film at the locations where the passive components need to be welded, forming the exposed contacts, thereby leaving a location for welding the passive components.

Furthermore, in step S5, the second SMT chip processing is used to solder the passive component and the substrate on the exposed contacts.

S6. Perform a second SMT patch treatment on the surface of the organic adhesive film.

S7. Molding the substrate and the radio frequency chip device, and obtaining a radio frequency module through cutting and packaging.

Furthermore, step S7 includes the following sub-steps:

S71. Perform laser printing on the substrate, and use resin for plastic sealing.

Laser printing refers to printing textures on the surface of the substrate during chip processing. Generally, the content of laser printing is related to the model of the RF chip. Molding is the last layer of protective film covering in the chip process. For example, in embodiments of the present invention, resin is used as the material used in molding.

S72. Cut the substrate to obtain a radio frequency module.

S73. Perform electromagnetic shielding on the radio frequency module, and the packaging is completed.

It should be noted that in the actual packaging process, step S72 has actually completed packaging of the radio frequency module with passive components, and electromagnetic shielding is a measure to protect the radio frequency device and its module before leaving the factory. If the packaging environment permits, step S73 can also be omitted.

Embodiments of the present invention also provide a radio frequency module obtained by the radio frequency module packaging method described in any of the above embodiments. Please refer to Figure 3. Figure 3 is a schematic structural diagram of a radio frequency module provided by an embodiment of the present invention. The radio frequency module 100 includes:

Substrate 1, which is divided into a contact layer with contacts 11 and a solder ball layer with a plurality of solder balls 12;

Radio frequency chip device 2. The radio frequency chip device 2 includes an exposed filter 21 and a plurality of chip solder balls 22 on the same side as the filter 21. The chip solder balls 22 and the contacts 11 form an electrical connection. connect;

A plurality of passive components 3, the passive components 3 forming electrical connections with the contacts 11;

Substrate protective layer 4, which covers the substrate 1 and the radio frequency chip device 2, and forms an opening 41 where the passive component and the contact point are connected;

Solid resin layer 5 covers the substrate protective layer 4 and the passive component 3 .

Furthermore, the substrate protective layer 4 is an organic glue film.

Furthermore, the radio frequency chip device 2 is electrically connected to the contact 11 of the substrate through the chip solder balls 22, and a filter cavity 6 is formed through the organic glue film.

Furthermore, the exposed surface of the filter 21 on the radio frequency chip is on the side of the radio frequency chip device 2 facing the filter cavity 6 .

The radio frequency module 100 is packaged through the BDMP process and can use passive components.

Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be implemented by instructing relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. The program can be stored in a computer-readable storage medium. During execution, the process may include the processes of the embodiments of each of the above methods. Wherein, the storage medium may be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM) or a random access memory (Random Access Memory, referred to as RAM), etc.

It should be noted that, in this document, the terms "comprising", "comprises" or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article or device that includes a series of elements not only includes those elements, It also includes other elements not expressly listed or inherent in the process, method, article or apparatus. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article or apparatus that includes that element.

Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus the necessary general hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is better. implementation. Based on this understanding, the technical solution of the present invention can be embodied in the form of a software product in essence or the part that contributes to the existing technology. The computer software product is stored in a storage medium (such as ROM/RAM, disk, CD), including several instructions to cause a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in various embodiments of the present invention.

The embodiments of the present invention are described above in conjunction with the accompanying drawings. What is disclosed is only the preferred embodiment of the present invention. However, the present invention is not limited to the above-mentioned specific implementations. The above-mentioned specific implementations are only illustrative. It is not intended to be limiting. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms and equivalent changes without departing from the spirit of the present invention and the scope protected by the claims, which all belong to the present invention. Within protection.

Claims

A packaging method for radio frequency modules, characterized in that the packaging method includes the following steps:

Front-end manufacturing of substrates;

Pre-assemble the radio frequency chip device including the filter on the surface of the substrate, and determine the fixed position of the radio frequency chip device;

Perform the first SMT patch processing on the substrate;

Carry out organic glue film coating treatment on the surface of the substrate;

Perform laser melting according to the position of the organic film required for passive components to form exposed contacts;

Perform a second SMT patch treatment on the surface of the organic adhesive film;

The substrate and the radio frequency chip device are plastic-sealed, and the radio frequency module is obtained by cutting and packaging.
The packaging method of a radio frequency module according to claim 1, characterized in that the step of pre-assembling the radio frequency chip device including the filter on the surface of the substrate and determining the fixed position of the radio frequency chip , the pre-assembly is used to ball-mount the substrate and the radio frequency chip.
The packaging method of a radio frequency module according to claim 1, wherein in the step of performing the first SMT patching process on the substrate, the first SMT patching process is used to The radio frequency chip device and the substrate are welded at the fixed position.
The packaging method of a radio frequency module according to claim 1, wherein in the step of performing a second SMT patch treatment on the surface of the organic adhesive film, the second SMT patch treatment is Welding the passive component and the substrate on the exposed contact.
The packaging method of a radio frequency module according to claim 1, wherein the step of plastic-sealing the substrate and the radio frequency chip device, and obtaining the radio frequency module through cutting and packaging includes the following sub-steps:

Perform laser printing on the substrate and use resin for plastic sealing;

Cut the substrate to obtain a radio frequency module;

Electromagnetic shielding is performed on the radio frequency module, and the packaging is completed.
A radio frequency module is characterized by including:

A substrate, which is divided into a contact layer with contacts and a solder ball layer with multiple solder balls;

A radio frequency chip device, the radio frequency chip device includes an exposed filter and a plurality of chip solder balls on the same side as the filter, and the chip solder balls form an electrical connection with the contact;

Passive component, the passive component forms an electrical connection with the contact;

A substrate protective layer covering the substrate and the radio frequency chip device, and forming an opening where the passive component meets the contact;

A solid resin layer covering the substrate protective layer and the passive component;

The radio frequency module is made by the packaging method of the radio frequency module described in any one of claims 1-5.
The radio frequency module of claim 6, wherein the substrate protective layer is an organic adhesive film.
The radio frequency module according to claim 7, wherein the radio frequency chip device is electrically connected to the contact point of the substrate through the chip solder ball, and a filter is formed through the organic adhesive film. Cavity.
The radio frequency module according to claim 8, wherein the exposed surface of the filter on the radio frequency chip is on a side of the radio frequency chip device facing the filter cavity.