Packaging structure and radio frequency module

Abstract

The utility model discloses a packaging structure and a radio frequency module, and relates to the technical field of radio frequency module packaging. A metal array composed of metal bodies is arranged around a to-be-shielded device, and a metal shielding layer is connected with one end, exposed out of a first plastic package layer, of each metal body and is connected with a substrate, so that cavity-divided shielding of the to-be-shielded device is realized, a complicated internal shielding structure is not needed, and a special process flow is not needed, and therefore, the shielding of the to-be-shielded device among all chips can be realized. Or the chip is shielded from the outside, a metal body can be freely arranged according to the position needing to be shielded, and the quality of the chip is not influenced; a metal array composed of vertical metal bodies is arranged around a to-be-shielded device, a shielding line arc is arranged on the metal bodies, and the shielding line arc spans the to-be-shielded device and forms a shielding cavity with the metal array, so that space waste caused by an arc line can be reduced; the number of layers of the metal arrays is increased, so that the metal bodies of the adjacent layers of metal arrays are distributed in a staggered mode, and / or the distribution density of shielding wire arcs is increased, and the electromagnetic shielding effect can be further enhanced.

Description

Technical Field

[0001] The utility model relates to the technical field of radio frequency module packaging, and in particular to a packaging structure and a radio frequency module. Background Art

[0002] A radio frequency (RF) module is a design that integrates two or more discrete devices including a filter, a duplexer / multiplexer (Diplexer / Duplexer / Multiplexer), a low noise amplifier (LNA), a power amplifier (PA) and a RF switch (Switch) into the same module, which can improve the integration of RF chips and make them further miniaturized.

[0003] In recent years, the distance between components in RF front-end modules has become smaller and smaller, resulting in increasingly serious mutual interference between components. In order to reduce the mutual interference between components / subsystems in the package module, partition shielding is usually used in the module manufacturing process to achieve electromagnetic shielding of sensitive components / subsystems.

[0004] In the current packaging structure, cavity shielding is generally achieved through metal shielding covers or ordinary shielding wires. When cavity shielding is performed on large-size chips through ordinary shielding wires, the wires are soldered to the pads on the substrate by ball welding so that the wires cross the chip. Since the amplitude across the chip is relatively large, the arc of the wire must be increased and the arc length must be increased, otherwise the wire will fall on the chip, which may cause electrical problems. When a metal cover is used for cavity shielding, the metal cover is large in size, resulting in a large volume for the entire package; the chip inside the metal cover cannot be protected by plastic sealing, which may cause moisture to penetrate into the metal cover, affecting the reliability of the product; at the same time, since the metal cover is relatively large in size, it may affect the flow of the plastic sealing material during the plastic sealing process, causing void problems. In addition, the cost of electromagnetic shielding with a metal cover will be relatively high.

[0005] Therefore, how to reduce the complexity of the packaging shielding structure is a key issue to be solved by this technical solution. Summary of the invention

[0006] In order to solve at least one of the technical problems mentioned in the background technology, the purpose of the present invention is to provide a packaging structure and a radio frequency module, which can reduce the complexity of the packaging shielding structure.

[0007] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0008] In a first aspect, an embodiment of the utility model provides a packaging structure, comprising

[0009] Substrates, RF devices, and metal shielding structures;

[0010] The substrate is provided with a soldering pad for soldering the radio frequency device to the first surface of the substrate;

[0011] The radio frequency device includes at least one device to be shielded;

[0012] The metal shielding structure includes a metal array arranged in a vertical direction and a metal shielding layer distributed in a horizontal direction; the metal array in the vertical direction and the metal shielding layer in the horizontal direction constitute a metal shielding cavity, and the metal shielding cavity accommodates the device to be shielded;

[0013] The metal array includes a plurality of metal bodies welded on the first surface of the substrate, and the metal array surrounds the device to be shielded.

[0014] Furthermore, there are at least two layers of the metal array surrounding the device to be shielded, and the metal bodies in each layer of the metal array are staggered with the metal bodies in the adjacent layer of the metal array.

[0015] Furthermore, the shape enclosed by the metal array is similar to the top view of the device to be shielded.

[0016] Furthermore, the metal body includes at least one of a metal column and a metal pier.

[0017] Furthermore, it also includes a first plastic packaging layer filled on the first surface of the substrate and the surface of the radio frequency device;

[0018] The height of the metal body is greater than the height of the device to be shielded, and the metal body is exposed on the first surface of the first plastic packaging layer;

[0019] The metal shielding layer is a metal film disposed on the first surface of the first plastic packaging layer by a sputtering process. The metal shielding layer is connected to an exposed end of the metal body and is connected to the substrate.

[0020] Furthermore, the height of the metal body is equal to the height of the first plastic packaging layer.

[0021] Furthermore, the radio frequency device includes a first type of device and / or a second type of device, the first type of device is a device that cannot be underfilled, and the second type of device is a device that requires underfill.

[0022] Furthermore, it also includes a second plastic packaging layer filled on the first surface of the substrate and the surface of the radio frequency device;

[0023] The metal shielding layer comprises a plurality of first shielding wire arcs, one end of the first shielding wire arc is connected to a metal body located on a first side of the device to be shielded, and the other end of the first shielding wire arc crosses the device to be shielded and is connected to a metal body located on a second side of the device to be shielded, wherein the first side is opposite to the second side;

[0024] The height of the second plastic packaging layer is greater than the height of the metal shielding layer.

[0025] Furthermore, the metal shielding layer also includes a plurality of second shielding wire arcs, one end of the second shielding wire arc is connected to a metal body located on a third side of the device to be shielded, and the other end spans the device to be shielded and is connected to a metal body located on a fourth side of the device to be shielded, wherein the third side is opposite to the fourth side.

[0026] Furthermore, the metal shielding layer also includes multiple third shielding wire arcs, one end of the third shielding wire arc is connected to the metal body located on the first side / second side of the device to be shielded, and the other end is connected to the metal body located on the third side / fourth side of the device to be shielded.

[0027] Furthermore, there are at least two layers of the metal array surrounding the device to be shielded, and the metal bodies in each layer of the metal array are staggered with the metal bodies in the adjacent layer of the metal array;

[0028] For each layer of the metal array, the first shielding arc is set using the above wiring method.

[0029] In a second aspect, an embodiment of the utility model further provides a radio frequency module, comprising any one of the above-mentioned packaging structures.

[0030] Compared with the prior art, the beneficial effects of the utility model are:

[0031] A metal array composed of metal bodies is arranged around the device to be shielded, and the metal shielding layer is connected to one end of the metal body exposed from the first plastic sealing layer, and is also connected to the substrate, so that the cavity shielding of the device to be shielded is realized. There is no complicated internal shielding structure, and no special process flow is required to achieve shielding between all chips or between the chip and the outside. The metal body can be freely arranged according to the position to be shielded, and the chip quality will not be affected.

[0032] A metal array consisting of vertical metal bodies is arranged around the device to be shielded, and shielding arcs are arranged on the metal bodies. The shielding arcs span the device to be shielded and form a shielding cavity with the metal array, which can reduce the space waste caused by the arcs.

[0033] Increasing the number of layers of the metal array so that the metal bodies of adjacent layers of the metal array are staggered and / or increasing the distribution density of the shielding arcs can further enhance the electromagnetic shielding effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic cross-sectional view of a substrate provided with a solder pad provided by the utility model;

[0035] Figure 2 A cross-sectional schematic diagram of welding a radio frequency device on a substrate provided by the utility model;

[0036] Figure 3 A cross-sectional schematic diagram of welding a metal array on a substrate provided by the utility model;

[0037] Figure 4 A top view of welding a metal array on a substrate provided by the utility model;

[0038] Figure 5 This is a cross-sectional schematic diagram of a method provided by the utility model after the first plastic sealing layer is filled;

[0039] Figure 6 A schematic cross-sectional view of a metal shielding layer covering a first plastic sealing layer provided by the utility model;

[0040] Figure 7 A schematic cross-sectional view of a multi-layer metal array provided by the utility model;

[0041] Figure 8 A schematic cross-sectional view of a method of realizing shielding by using a shielding wire arc in one direction provided by the utility model;

[0042] Fig. 9 A top view of a method of realizing shielding by using a shielding wire arc in one direction provided by the utility model;

[0043] Fig.10 A cross-sectional schematic diagram of a filling second plastic sealing layer provided by the utility model;

[0044] Fig.11 A top view of a method of realizing shielding by using shielding arcs in two directions provided by the utility model;

[0045] Fig.12 A top view of a method of realizing shielding by using shielding arcs in three directions provided by the utility model;

[0046] Fig.13 A top view of a shielding arc arranged on a multi-layer metal array provided by the utility model;

[0047] Fig.14 A schematic diagram of a radio frequency module provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the utility model are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0049] With the development of communication technology, the trend of RF modularization of user equipment (UE) such as mobile phones is very obvious. Different from the early 3G and 4G era, in the multi-frequency and multi-mode era, especially after the gradual commercialization and popularization of 5G, mobile phones need a lot of devices to meet the support requirements of global frequency bands, and the RF front-end (RF front-end) becomes more complex. Due to the limited design space of mobile phone motherboards, the trend of modularization, integration and miniaturization begins to emerge naturally. The increasingly tense contradiction between the increasing number of RF front-end devices and the available area of ​​​​Printed Circuit Board (PCB) has prompted the gradual development of highly integrated RF front-end module products. Based on the use of high-performance filters as core components, according to the specific components used, module products also include FEMiD (integrated switch, filter and duplexer), PAMiD (integrated multi-mode multi-band PA and FEMiD), LPAMiD (PAMiD plus LNA), DiFEM (RF switch and filter), LFEM (Switch, LNA and Filter), etc.

[0050] However, during operation, RF chips are susceptible to electrostatic breakdown, mechanical vibration, humidity, etc. The physical barrier provided by the package can increase the stability and reliability of the chip; at the same time, electromagnetic shielding and isolation can also absorb external electromagnetic interference, reduce internal electromagnetic coupling and interference, and provide heat dissipation pathways and protection against physical vibration and impact for the chip. Among them, electromagnetic interference (EMI) refers to the interference phenomenon caused by the interaction of electromagnetic waves with electronic components. There are two types of interference: conducted interference and radiated interference. Conducted interference refers to the coupling (interference) of a signal on an electrical network to another electrical network through a conductive medium. Radiated interference refers to the coupling (interference) of an interference source's signal to another electrical network through space. In high-speed PCB and system design, high-frequency signal lines, integrated circuit pins, various connectors, etc. may become radiated interference sources with antenna characteristics, which can emit electromagnetic waves and affect the normal operation of other systems or other subsystems within the system.

[0051] In recent years, the distance between components in RF front-end modules has become smaller and smaller, resulting in increasingly serious mutual interference between components. In order to reduce the mutual interference between components / subsystems in the package module, partition shielding is usually used in the module manufacturing process to achieve electromagnetic shielding of sensitive components / subsystems.

[0052] When using ordinary shielding wires to perform cavity shielding on large-size chips, the wires are soldered to the pads on the substrate by ball bonding so that the wires cross the chip. Since the cross-chip amplitude is relatively large, the arc of the wire must be increased, otherwise the wire will fall on the chip, which may cause electrical problems.

[0053] When a metal cover is used for cavity shielding, the metal cover is large, which makes the entire package large; the chip inside the metal cover cannot be protected by plastic sealing, which may cause moisture to penetrate into the metal cover and affect the reliability of the product; at the same time, due to the large volume of the metal cover, it may affect the flow of the plastic sealing material during the plastic sealing process, causing void problems. In addition, the cost of electromagnetic shielding with a metal cover is relatively high.

[0054] In order to solve the above problems existing in the prior art, the embodiments of the present invention provide a packaging structure and a radio frequency module, which are described in detail below.

[0055] In a first aspect, an embodiment of the utility model provides a packaging structure.

[0056] Embodiment 1:

[0057] A packaging structure includes a substrate, a radio frequency device, and a metal shielding structure;

[0058] like Figure 1 As shown, Figure 1 A schematic diagram of a substrate provided with solder pads provided by the utility model. A plurality of solder pads 102 are provided on the substrate 101 for subsequently soldering radio frequency devices on the first surface of the substrate 101 .

[0059] like Figure 2 As shown, Figure 2 The cross-sectional view of welding a radio frequency device on a substrate provided by the present invention is as follows. The radio frequency device 103 includes at least one device 1031 to be shielded.

[0060] The RF device 103 is welded on the first surface of the substrate 101. The welded RF device 103 is usually a device that cannot be bottom-filled, such as a filter, or a device that requires bottom-filling, such as an RF switch. When the welded RF device 103 includes a device that requires bottom-filling, the device that requires bottom-filling also needs to be bottom-filled. The process can refer to the prior art and will not be expanded here.

[0061] The metal shielding structure includes a metal array arranged in a vertical direction and a metal shielding layer distributed in a horizontal direction; the metal array in the vertical direction and the metal shielding layer in the horizontal direction constitute a metal shielding cavity, and the metal shielding cavity accommodates the device to be shielded.

[0062] like Figure 3 As shown, Figure 3 A cross-sectional schematic diagram of welding a metal array on a substrate provided by the utility model.

[0063] Metal array (due to Figure 3 This is a cross-sectional view. The metal array is not Figure 3 ) includes a plurality of metal bodies 1041 welded on the first surface of the substrate 101 , the metal array surrounds the device to be shielded 1031 , and the height of the metal bodies 1041 is higher than the height of the device to be shielded 1031 .

[0064] The metal body 1041 can be a metal column or a metal pier. The metal pier is wider or called a platform. The metal column is a columnar object with a more slender shape. The processing methods of the two may also be different. The metal pier is mostly cast, and the metal column is mostly forged.

[0065] The metal body 1041 is welded on the substrate 101 through the welding pad 102 , so that a metal array is arranged around the device to be shielded 1031 , wherein the height of the metal body 1041 is higher than the height of the device to be shielded 1031 .

[0066] like Figure 4 As shown, Figure 4 A top view of welding a metal array on a substrate provided by the utility model.

[0067] The metal array 104 is preferably a pattern similar to the top view of the device to be shielded 1031, which can save the area of ​​the substrate 101, for example Figure 4 In the figure, the RF devices 103 are all rectangular, including the device to be shielded 1031 which is also rectangular, and the metal array 104 is also arranged in a rectangular shape, surrounding the device to be shielded 1031. Of course, the metal array 104 can also be other shapes, such as circular, elliptical, square or even some irregular shapes, etc., which is not limited in the present invention.

[0068] In the first embodiment, the metal shielding layer is a metal film disposed on the first surface of the first plastic packaging layer by a sputtering process.

[0069] like Figure 5 As shown, Figure 5 This is a cross-sectional schematic diagram after the first plastic sealing layer is filled provided by the utility model.

[0070] The first plastic packaging layer 105 is filled on the first surface of the substrate 101 and the surface of the RF device 103 , and the metal body 1041 is exposed on the first surface of the first plastic packaging layer 105 ;

[0071] The first plastic packaging layer 105 may be made of epoxy plastic packaging material or other commonly used materials, which is not limited in the present application.

[0072] Due to the process or other reasons, the height of the metal body 1041 may be greater than or less than the thickness of the first plastic layer 105 composed of the plastic material. In this case, the structure needs to be polished to expose the metal body 1041, and polishing the upper surface of the first plastic layer 105 to make it flat is also conducive to the subsequent process. Preferably, the thickness of the first plastic layer 105 is equal to the height of the metal body 1041, such as Figure 5 As shown, one end of the metal body 1041 is just exposed on the upper surface of the first plastic packaging layer 105 .

[0073] like Figure 6 As shown, Figure 6 A cross-sectional schematic diagram of a metal shielding layer covered on a first plastic packaging layer provided by the utility model.

[0074] The metal shielding layer 106 is a metal film disposed on the first surface of the first plastic packaging layer 105 by a sputtering process. The metal shielding layer 106 is connected to an exposed end of the metal body 1041 and is also connected to the substrate 101 .

[0075] Metal shielding layer 106 (ie Figure 6 The metal body 1041 is directly in contact with (i.e. connected to) the metal body 1041 and covers the entire first plastic packaging layer 105 and is connected to the substrate 101. In this way, the sputtered metal shielding layer 106 and the metal array form a shielding cavity to complete electromagnetic shielding for the shielding device 1031.

[0076] Sputter is a method of vacuum coating. Its working principle is to inject argon gas into a high vacuum state, and cause the gas to glow discharge under the action of a strong electric field, generate argon positive ions, and accelerate to form a high-energy ion flow to bombard the surface of the target material, so that the target atoms are separated from the surface and sputtered (deposited) onto the surface of the silicon wafer to form a thin film.

[0077] The metal film formed by sputtering has a bright mirror-like surface, no oxidation, high purity, good particles, uniform film layer, and thickness that meets certain requirements. The film thickness is well controllable and repeatable; it is suitable for large-scale automated production.

[0078] From the characteristics introduced above, it can be seen that the application of sputtering in the packaging of RF modules is worth studying. It has good packaging effect (the surface of the metal film formed by sputtering is as bright as a mirror, without oxidation, high purity, good particles, uniform film layer, and thickness meets certain requirements), good operability (good controllability and repeatability of film thickness), and is suitable for automated production, which can save labor costs.

[0079] After laser film breaking exposes multiple pads on the substrate, there may be impurities on the surface of the structure, which need to be removed. At the same time, a clean surface is also an important factor affecting whether sputtering can proceed smoothly. Therefore, the degree of cleaning before sputtering is an important indicator of the success of sputtering. The wafer spin rinse dryer (SRD) can be used for cleaning.

[0080] SRD is a common semiconductor cleaning and drying equipment. Specifically, the wafer needs to be cleaned and dried after the wet chemical process, and SRD can automatically process the entire wafer. The job of SRD is to rinse and dry batches of wafers in the wafer boat. The wafers are usually loaded into a stainless steel drum or chamber, and then deionized water is injected while rotating to rinse off any particles left over from the previous process steps. Wafers are usually dried by rotating the wafer at a speed of about 3000-10000rpm while heated nitrogen is injected into the chamber. Of course, static electricity will accumulate during drying, which may cause particles to adhere to the surface and even damage some precision equipment. The occurrence of such phenomena can be reduced by using static elimination components.

[0081] The SRD equipment is equipped with a resistivity probe that monitors the chemical concentration in the chamber to ensure complete removal of the chemicals. Resistivity is a measure of the degree to which a substance hinders the flow of electricity. In the SRD equipment, if the resistivity of the rinse water decreases, this may mean that the concentration of chemicals in the water has increased, that is, there is still chemical solution remaining on the surface of the wafer. By monitoring the resistivity, the equipment can ensure the thoroughness of the rinse process, thereby improving the quality of cleaning.

[0082] Equipped with a nitrogen heater, spot-free drying is possible. Nitrogen is an inert gas that does not chemically react with the material on the wafer surface, thus preventing any chemical damage to the wafer during the drying process. When the nitrogen is heated, it can more effectively absorb moisture from the wafer surface, thereby improving the efficiency of drying. In addition, since the heated nitrogen flow can form a uniform heat flow on the wafer surface, this helps to ensure the uniformity of wafer drying and prevent the formation of water spots on the wafer surface. Therefore, the nitrogen heater is an important configuration in SRD equipment, which can help improve the drying effect and quality after semiconductor cleaning.

[0083] Some common factors affecting pre-cleaning:

[0084] 1) Rinse time: The length of the rinse time will affect the removal effect of the chemical solution. If the rinse time is too short, some chemical solution may remain on the wafer surface; if the rinse time is too long, it may cause a waste of resources.

[0085] 2) Drying time: The length of drying time will affect the degree of drying of the wafer. If the drying time is too short, moisture may remain on the surface of the wafer; if the drying time is too long, thermal damage may be caused to the wafer.

[0086] 3) Rotation speed: The rotation speed affects the centrifugal force, thus affecting the rinsing and drying effects. If the rotation speed is too slow, the chemical solution and water may not be effectively removed; if the rotation speed is too fast, it may cause mechanical damage to the wafer.

[0087] 4) Nitrogen flow rate and temperature: The flow rate and temperature of nitrogen will affect the efficiency and quality of drying. If the flow rate of nitrogen is too slow or the temperature is too low, it may not be able to effectively remove moisture; if the flow rate of nitrogen is too fast or the temperature is too high, it may cause thermal damage to the wafer.

[0088] Optionally, after cleaning and drying, the structure to be sputtered may be baked to heat the device to a preset temperature, thereby facilitating sputtering.

[0089] The specific process of sputtering:

[0090] In the Sputter chamber filled with a small amount of Ar. The target is the cathode and the wafer is the anode. When the inter-electrode voltage is very small, there are only a small number of ions and electrons. When the voltage between the cathode (target) and the anode increases, the charged particles accelerate under the action of the electric field, the energy increases, and they collide with the electrode or neutral gas atoms to produce more charged particles. When the voltage increases further, a negative resistance effect, namely the "avalanche" phenomenon, will occur. At this time, the ions bombard the cathode, knocking out cathode atoms and secondary electrons. The secondary electrons collide with neutral atoms to produce more ions, which bombard the cathode again to produce secondary electrons, and so on. When the current density reaches about 0.01A / era, the current will increase with the increase of voltage, forming an abnormal glow discharge of high-density plasma, and high-energy ions bombard the cathode (target) to produce sputtering. The sputtered high-energy target particles are deposited on the anode (wafer), thereby achieving the purpose of sputtering.

[0091] Factors affecting sputtering:

[0092] 1) Energy of the incident particle

[0093] Sputtering only occurs when the energy of the incident particles exceeds a certain threshold (about 101eV). Within a certain threshold range (about keV), the sputtering rate increases with increasing energy, while excessive energy will cause the incident particles to be injected into the target material, reducing the sputtering rate.

[0094] 2) Angle of incident particles

[0095] Oblique incidence at a certain angle is beneficial to improving the sputtering rate.

[0096] 3) Type of incident particles

[0097] The sputtering rate of heavy particles is higher than that of light particles.

[0098] 4) Target temperature

[0099] As the temperature increases, the bonding force between target atoms decreases, and sputtering occurs with a smaller energy of the incident particles.

[0100] 5) Working pressure and argon concentration

[0101] When the gas pressure is very low, there is little argon that can be ionized, and there is little Ar+ bombarding the target material, so the sputtering rate is very low, and it may even be impossible to ignite. As the gas pressure increases, the concentration of argon increases, and the probability of the sputtered target atoms colliding with these gases in the process of flying to the substrate increases, and the distribution of the target atoms becomes uniform, thereby improving the uniformity of the film layer. At the same time, the Ar+ density increases with the increase of the argon concentration, and the number of sputtered target atoms will also increase, thereby increasing the sputtering rate. However, excessive gas pressure will reduce the sputtering rate and film quality, because excessive gas pressure will increase the number of collisions between target atoms and gas, and the target atoms will lose a lot of energy, making the energy of the atoms deposited on the substrate too low, thereby affecting the adhesion and density of the film layer. At the same time, excessive gas pressure will cause the mean free path of ions to decrease, and too many collisions with gas molecules will also lead to a decrease in deposition rate.

[0102] Embodiment 2:

[0103] like Figure 7 As shown, Figure 7 A cross-sectional schematic diagram of a multi-layer metal array provided by the utility model.

[0104] The difference from the first embodiment is that at least two layers of metal arrays 104 surround the device to be shielded 1031 , and the metal bodies 1041 in each layer of the metal array 104 are staggered with the metal bodies 1041 in the adjacent layer of the metal array 104 .

[0105] Since the density process limitation of setting the metal array may affect the shielding effect, the shielding effect can be enhanced by setting a multi-layer metal array in the second embodiment.

[0106] The staggered distribution of metal bodies in adjacent layers can increase the distribution density of the metal bodies, thereby further enhancing the electromagnetic shielding effect.

[0107] Embodiment three:

[0108] like Figure 8 As shown, Figure 8 A cross-sectional schematic diagram of a shielding device provided by the utility model using a shielding wire arc in one direction to achieve shielding.

[0109] The difference from Example 1 is that the metal shielding layer includes multiple first shielding wire arcs 107, one end of the first shielding wire arc 107 is connected to the metal body 1041 located on the first side of the device to be shielded 1031, and the other end crosses the device to be shielded 1031 and is connected to the metal body 1041 located on the second side of the device to be shielded 1031, wherein the first side is opposite to the second side.

[0110] The first shielding line arc 107 spans across the device to be shielded 1031 and forms a shielding cavity with the metal array.

[0111] like Fig. 9 As shown, Fig. 9 A top view of a shielding arc in one direction for realizing shielding provided by the utility model.

[0112] Fig. 9 In the figure, the first side is the left side of the device to be shielded 1031, and the second side is the right side of the device to be shielded 1031; it should be noted that the first side can be any side of the device to be shielded 1031, and it is only necessary to ensure that the first side is opposite to the second side so that the shielding line arc presents one direction.

[0113] It should be understood that this figure is only a simple example. A metal arc is welded on a metal body 1041 in the metal array 104. In actual applications, more or fewer metal arcs can be welded on a metal body 1041, and this application does not limit it.

[0114] Specifically, the first shielding wire arc 107 is welded to the metal bodies 1041 on both sides of the device to be shielded 1031 by ball welding, and the arc is raised and the arc length is increased to form a shape that spans the device to be shielded 1031. Finally, multiple first shielding wire arcs 107 and the metal array 104 form a metal shielding structure.

[0115] The shielded wire arc is made of metal. The advantages of welding metal wire arcs include reducing complex processes (no etching or electroplating processes are required to achieve interconnection, improving production efficiency), achieving low cost and high efficiency (fewer process requirements, fewer machines), and realizing flexible application of multiple wire arcs and multiple arc heights.

[0116] like Fig.10 As shown, Fig.10 This is a cross-sectional schematic diagram of a filling second plastic sealing layer provided by the utility model.

[0117] The second plastic encapsulation layer 108 is filled on the first surface of the substrate 101 and the surface of the RF device 103 and covers the first shielding arc 107 , that is, the height of the second covering layer 108 is greater than the height of the metal shielding layer;

[0118] The second plastic packaging layer 108 also uses epoxy plastic packaging material, and may also use other commonly used materials, which is not limited in the present application.

[0119] Embodiment 4:

[0120] like Fig.11 As shown, Fig.11 A top view of the utility model for realizing shielding by using shielding wire arcs in two directions.

[0121] On the basis of the third embodiment, the metal shielding layer further includes a plurality of second shielding wire arcs 109, one end of the second shielding wire arc 109 is connected to the metal body 1041 located on the third side of the device to be shielded 1031, and the other end crosses the device to be shielded 1031 and is connected to the metal body 1041 located on the fourth side of the device to be shielded 1031, wherein the third side is opposite to the fourth side;

[0122] Fig.11 In the figure, the third side is above the device to be shielded 1031, and the fourth side is below the device to be shielded 1031. It should be understood that the metal array 104 can be divided here according to actual conditions. For example, when the metal array 104 is circular, it can be divided into four equal parts.

[0123] By welding shielding arcs in two directions on the metal array 104 , the distribution density of the shielding arcs can be increased, thereby enhancing the shielding effect.

[0124] Embodiment five:

[0125] like Fig.12 As shown, Fig.12 A top view of the utility model for realizing shielding by using shielding wire arcs in three directions.

[0126] Based on the fourth embodiment, the metal shielding layer also includes multiple third shielding wire arcs 110, one end of the third shielding wire arc 110 is connected to the metal body 1041 located on the first side / second side of the device to be shielded 1031, and the other end is connected to the metal body 1041 located on the third side / fourth side of the device to be shielded 1031.

[0127] By welding shielding arcs in three directions on the metal array 104 , the distribution density of the shielding arcs can be increased, thereby enhancing the shielding effect.

[0128] by Fig.12 For example, the three directions include horizontal, vertical and oblique directions. It should be noted that the oblique direction can be an inclination from the lower left to the upper right, or an inclination from the lower right to the upper left. This application does not limit this.

[0129] Similarly, in order to further improve the distribution density of the shielding wire arcs, the shielding wire arcs in four directions can be welded. The principle is the same as above and will not be repeated here.

[0130] Embodiment six:

[0131] like Fig.13 As shown, Fig.13 A top view of a shielding wire arc arranged on a multi-layer metal array provided by the utility model.

[0132] On the basis of the third embodiment, at least two layers of metal arrays 104 surround the device to be shielded 1031, and the metal bodies 1041 in each layer of the metal array 104 are staggered with the metal bodies 1041 in the adjacent layer of the metal array 104;

[0133] For each layer of the metal array 104 , the first shielding arc 107 is arranged by using the wiring method in the third embodiment, which will not be described in detail here.

[0134] That is, the second embodiment is combined with the third embodiment, and shielding arcs are arranged on a multi-layer metal array. Compared with a single-layer metal array, the wiring density is obviously higher and the shielding effect is stronger.

[0135] Similarly, the second embodiment may be combined with the fourth embodiment, or the second embodiment may be combined with the fifth embodiment, so as to further enhance the electromagnetic shielding effect, and the principle is the same as above.

[0136] In a second aspect, an embodiment of the utility model also provides a radio frequency module.

[0137] Embodiment seven:

[0138] like Fig.14 As shown, Fig.14 A schematic diagram of a radio frequency module provided in an embodiment of the utility model.

[0139] Depending on the specific devices used, actual module products include FEMiD (integrated switch, filter and duplexer), PAMiD (integrated multi-mode multi-band PA and FEMiD), LPAMiD (PAMiD plus LNA), DiFEM (RF switch and filter), LFEM (Switch, LNA and Filter), etc.

[0140] Fig.14 The RF module shown may be an LPAMiD product, and its operating frequency band includes but is not limited to B8 and B20. Fig.14 The packaging structure shown includes a shell, a substrate arranged inside the shell, a radio frequency switch arranged on the substrate, a filter arranged on the substrate, a power amplifier (PA) arranged on the substrate, a low noise amplifier (LNA) arranged on the substrate, and various necessary input and output ports (AUX1, OUT1, power port, antenna interface, radio frequency signal input interface, output port, TRX1 and TRX2, etc.) extending from the internal device to the outside of the shell.

[0141] Among them, a metal array is arranged between at least one of Switch, Filter1, Filter2, PA and LNA and other devices, and a metal arc crossing the device to be shielded is arranged on the metal array. The metal arc and the metal array form a metal shielding layer, which can isolate the device to be shielded from other devices and realize electromagnetic shielding between the device to be shielded and other devices.

[0142] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0143] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0144] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection 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 this application can be understood according to the specific circumstances.

[0145] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0146] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If present, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0147] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

Claims

1. A packaging structure, characterized in that: Including substrate, radio frequency device, and metal shielding structure; The substrate is provided with a soldering pad for soldering the radio frequency device to the first surface of the substrate; The radio frequency device includes at least one device to be shielded; The metal shielding structure includes a metal array arranged in a vertical direction and a metal shielding layer distributed in a horizontal direction; the metal array in the vertical direction and the metal shielding layer in the horizontal direction constitute a metal shielding cavity, and the metal shielding cavity accommodates the device to be shielded; The metal array includes a plurality of metal bodies welded on the first surface of the substrate, and the metal array surrounds the device to be shielded.

2. The packaging structure according to claim 1, characterized in that: There are at least two layers of the metal array surrounding the device to be shielded, and the metal bodies in each layer of the metal array are staggered with the metal bodies in the adjacent layer of the metal array.

3. The packaging structure according to claim 1, characterized in that: The figure enclosed by the metal array is similar to the top view of the device to be shielded.

4. The packaging structure according to claim 1, characterized in that: The metal body includes at least one of a metal column and a metal pier.

5. The packaging structure according to claim 1 or 3, characterized in that: It also includes a first plastic packaging layer filled on the first surface of the substrate and the surface of the radio frequency device; The height of the metal body is greater than the height of the device to be shielded, and the metal body is exposed on the first surface of the first plastic packaging layer; The metal shielding layer is a metal film disposed on the first surface of the first plastic packaging layer by a sputtering process. The metal shielding layer is connected to an exposed end of the metal body and is connected to the substrate.

6. The packaging structure according to claim 5, characterized in that: The height of the metal body is equal to the height of the first plastic packaging layer.

7. The packaging structure according to claim 1, characterized in that: The radio frequency devices include first-category devices and / or second-category devices. The first-category devices are devices that cannot be underfilled, and the second-category devices are devices that require underfill.

8. The packaging structure according to claim 1, characterized in that: It also includes a second plastic packaging layer filled on the first surface of the substrate and the surface of the radio frequency device; The metal shielding layer comprises a plurality of first shielding wire arcs, one end of the first shielding wire arc is connected to a metal body located on a first side of the device to be shielded, and the other end of the first shielding wire arc crosses the device to be shielded and is connected to a metal body located on a second side of the device to be shielded, wherein the first side is opposite to the second side; The height of the second plastic packaging layer is greater than the height of the metal shielding layer.

9. The packaging structure according to claim 8, characterized in that: The metal shielding layer also includes a plurality of second shielding wire arcs, one end of which is connected to a metal body located on a third side of the device to be shielded, and the other end of which spans the device to be shielded and is connected to a metal body located on a fourth side of the device to be shielded, wherein the third side is opposite to the fourth side.

10. The packaging structure according to claim 9, characterized in that: The metal shielding layer also includes a plurality of third shielding wire arcs, one end of each third shielding wire arc is connected to a metal body located on the first side / second side of the device to be shielded, and the other end is connected to a metal body located on the third side / fourth side of the device to be shielded.

11. The packaging structure according to claim 8, characterized in that: There are at least two layers of the metal array surrounding the device to be shielded, and the metal bodies in each layer of the metal array are staggered with the metal bodies in the adjacent layer of the metal array; For each layer of the metal array, the first shielding arc is set using the wiring method in claim 8.

12. A radio frequency module, characterized in that: The radio frequency module includes a packaging structure as described in any one of claims 1-11.

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