Embedded antenna chip packaging structure and preparation method

Abstract

The present invention relates to the technical field of integrated circuit chips, and in particular to an embedded antenna chip packaging structure and a preparation method thereof. The present invention designs the antenna structure of the embedded antenna chip packaging structure into a laminated antenna structure, wherein the laminated antenna structure comprises a distance control layer, an antenna device located on the surface of the distance control layer, and a protective layer located on the surface of the antenna device, wherein the Young's modulus of the protective layer is higher than that of the distance control layer. Since the antenna structure occupies a large area in the entire embedded antenna chip packaging structure, the warping problem of the embedded antenna chip packaging structure can be greatly alleviated by setting the laminated antenna structure and making the Young's modulus of the protective layer higher than that of the distance control layer.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuit chips, and in particular to an embedded antenna chip packaging structure and a preparation method thereof. Background Art

[0002] With the increasing commercial application of high-frequency systems such as 4G / 5G communication systems, the Internet of Things, and millimeter-wave wireless communications, especially short-distance big data wireless transmission systems, passive imaging systems, automotive radar systems, etc., the requirements for high performance, miniaturization, high integration, and low cost are becoming increasingly higher.

[0003] Therefore, in order to reduce the influence of parasitic parameters of system interconnection, more and more passive systems are integrated into the package. Antennas are typical passive components in communication systems. The industry has been conducting research on antenna packaging (AiP), mainly focusing on the integration of substrates such as LTCC and LCP with active chips. With the application of fan-out packaging in high-frequency fields such as automotive radar, passive components represented by antennas have also begun to be integrated into fan-out packages.

[0004] In the prior art, the AiP structure based on fan-out packaging generally adopts a multi-layer re-distributed layer (RDL) antenna structure or an embedded prefabricated antenna structure. When the antenna is buried in the fan-out package using an embedded prefabricated antenna structure, due to the requirements of the antenna package thickness design, the existing AiP structure has high cost and low reliability, and is prone to warping problems. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides an embedded antenna chip packaging structure and a preparation method.

[0006] In order to achieve the above-mentioned objectives, an embodiment of the present invention provides an embedded antenna chip packaging structure, comprising: a redistribution layer, a chip structure and a laminated antenna structure located on the first surface of the redistribution layer, a plastic packaging structure located on the first surface of the redistribution layer and encapsulating the chip structure and the laminated antenna structure, the chip structure and the laminated antenna structure are electrically connected through the redistribution layer, the laminated antenna structure comprises a distance control layer located on the first surface of the redistribution layer, an antenna device located on the surface of the distance control layer, and a protective layer located on the surface of the antenna device, wherein the thickness of the distance control layer is adapted to the corresponding antenna device, and the Young's modulus of the protective layer is higher than that of the distance control layer.

[0007] Optionally, the size of the protection layer is greater than or equal to the size of the distance control layer.

[0008] Optionally, a stress buffer layer is formed between the distance control layer and the protective layer.

[0009] Optionally, the material of the distance control layer is different from that of the protective layer, and the dielectric loss of the distance control layer and the protective layer is less than or equal to that of the plastic packaging structure.

[0010] Optionally, a first distance between a surface of the antenna device close to the protective layer and the first surface of the redistribution layer is greater than a second distance between a back surface of the chip structure and the first surface of the redistribution layer.

[0011] Optionally, the distance control layer and / or the protective layer is a heterojunction cavity structure, the heterojunction cavity structure includes a heterojunction center part and a heterojunction edge part at its edge, the heterojunction center part faces the antenna device, and the dielectric loss of the heterojunction center part is lower than that of the heterojunction edge part.

[0012] Optionally, an annular metal transition layer is provided between the central portion of the heterojunction and the edge portion of the heterojunction.

[0013] Optionally, when the distance control layer and the protective layer are both heterojunction cavity structures, the heterojunction center part of the distance control layer and the heterojunction center part of the protective layer have different sizes, and the heterojunction interface of the distance control layer and the heterojunction interface of the protective layer form an inner horn or outer horn structure.

[0014] The embodiment of the present invention further provides a method for preparing an embedded antenna chip packaging structure, comprising:

[0015] Provided are a laminated antenna structure and a chip structure, wherein the laminated antenna structure comprises a distance control layer, an antenna device located on a surface of the distance control layer, and a protective layer located on a surface of the antenna device, wherein the thickness of the distance control layer is adapted to the corresponding antenna device, and the Young's modulus of the protective layer is higher than the Young's modulus of the distance control layer;

[0016] Providing a carrier board, laminating the chip structure and the laminated antenna structure at corresponding positions on the carrier board surface, wherein the front side of the chip structure faces the carrier board surface, the distance control layer of the laminated antenna structure faces the carrier board surface, and forming a plastic sealing structure on the carrier board surface, wherein the plastic sealing structure performs plastic sealing on the chip structure and the laminated antenna structure;

[0017] Peeling off the plastic packaging structure from the carrier board;

[0018] A redistribution layer is formed on the surface of the plastic package structure where the laminated antenna structure and the chip structure are exposed.

[0019] Optionally, the method for preparing the laminated antenna structure includes: providing a protective layer substrate, forming an antenna device on the surface of the protective layer substrate, forming a distance control material layer on the antenna device and the surface of the protective layer substrate, and cutting using a cutting process to form the laminated antenna structure.

[0020] Optionally, the method further includes: after forming a distance control material layer on the surface of the antenna device and the protective layer substrate, thinning the distance control material layer to achieve a set thickness.

[0021] Optionally, when cutting is performed using a cutting process, the protective layer and the distance control layer are cut separately, and the size of the protective layer is larger than the size of the distance control layer.

[0022] Optionally, the distance control layer and / or the protective layer is a heterojunction cavity structure, the heterojunction cavity structure includes a heterojunction center part and a heterojunction edge part at its edge, the heterojunction center part faces the antenna device, and the dielectric loss of the heterojunction center part is lower than that of the heterojunction edge part.

[0023] Optionally, when the distance control layer is a heterojunction cavity structure, the specific method for forming the distance control material layer includes: after the distance control material layer is formed on the surface of the antenna device and the protective layer substrate, the distance control material layer at the position directly opposite the antenna device is removed and refilled with a second material, and the filled second material serves as the heterojunction center part of the distance control layer formed subsequently.

[0024] Optionally, before refilling the second material, a metal transition layer is formed on the sidewall of the groove formed by removing the distance control material layer, and then the second material is refilled in the groove, so that an annular metal transition layer is provided between the central part of the heterojunction and the edge part of the heterojunction.

[0025] Optionally, when the protective layer is a heterojunction cavity structure, the specific method for forming the protective layer includes: providing a protective layer substrate, removing a portion of the thickness of the protective layer material at a position on the protective layer substrate corresponding to the antenna device to form a refilled third material, and the filled third material serves as the heterojunction center part of the protective layer formed subsequently.

[0026] Optionally, before refilling the third material, a metal transition layer is deposited on the sidewall of the groove formed by removing part of the thickness of the protective layer material, and then the third material is refilled in the groove, so that an annular metal transition layer is provided between the central part and the edge part of the heterojunction finally formed.

[0027] Optionally, when the distance control layer and the protective layer are both heterojunction cavity structures, the heterojunction center part of the distance control layer and the heterojunction center part of the protective layer have different sizes, and the heterojunction interface of the distance control layer and the heterojunction interface of the protective layer form an inner horn or outer horn structure.

[0028] In summary, the beneficial effects of the present invention are:

[0029] The present invention designs the antenna structure of the embedded antenna chip packaging structure into a laminated antenna structure, wherein the laminated antenna structure includes a distance control layer, an antenna device located on the surface of the distance control layer, and a protective layer located on the surface of the antenna device, wherein the Young's modulus of the protective layer is higher than that of the distance control layer. Since the antenna structure occupies a large area in the entire embedded antenna chip packaging structure, the warping problem of the embedded antenna chip packaging structure can be greatly alleviated by setting the laminated antenna structure and making the Young's modulus of the protective layer higher than that of the distance control layer.

[0030] In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic diagram of a top view of an embedded antenna chip packaging structure provided by an embodiment of the present invention;

[0032] Figure 2 For an embodiment of the present invention Figure 1 A schematic diagram of the cross-sectional structure of the embedded antenna chip package structure along line AA';

[0033] Figure 3 Another embodiment of the present invention Figure 1 A schematic diagram of the cross-sectional structure of the embedded antenna chip package structure along line AA';

[0034] Figure 4 Another embodiment of the present invention Figure 1 A schematic diagram of the cross-sectional structure of the embedded antenna chip package structure along line AA';

[0035] Figure 5 Another embodiment of the present invention Figure 1 A schematic diagram of the cross-sectional structure of the embedded antenna chip package structure along line AA';

[0036] Figure 6 Another embodiment of the present invention Figure 1 A schematic diagram of the cross-sectional structure of the embedded antenna chip package structure along line AA';

[0037] Figure 7A schematic flow chart of a method for preparing an embedded antenna chip packaging structure provided by an embodiment of the present invention;

[0038] Figure 8 A schematic diagram of a process for preparing a laminated antenna structure provided by an embodiment of the present invention;

[0039] Figures 9 to 16 A schematic cross-sectional structure diagram of a preparation process of an embedded antenna chip packaging structure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to facilitate understanding by those skilled in the art, the present invention will be further described in detail below in conjunction with specific embodiments.

[0041] The embodiment of the present invention first provides a buried antenna chip packaging structure, please refer to Figure 1 and Figure 2 , Figure 1 It is a top view structural diagram of the embedded antenna chip packaging structure. Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure along line AA'. In the present embodiment, a packaging structure including a chip structure and two stacked antenna structures is taken as an example for explanation. In other embodiments, a packaging structure may include one or more chip structures, and a packaging structure may include one or more stacked antenna structures, wherein the position and spacing of the chip structure and the stacked antenna structure may also be designed and determined as needed, and are not limited here.

[0042] In this embodiment, the embedded antenna chip packaging structure includes: a redistribution layer 100, a chip structure 200 and a stacked antenna structure 300 located on the first surface of the redistribution layer 100, a plastic packaging structure 400 located on the first surface of the redistribution layer 100 and encapsulating the chip structure 200 and the stacked antenna structure 300, the chip structure 200 and the stacked antenna structure 300 are electrically connected through the redistribution layer 100, and the stacked antenna structure 300 includes a distance control layer 310 located on the first surface of the redistribution layer 100, an antenna device 320 located on the surface of the distance control layer 310, and a protective layer 330 located on the surface of the antenna device 320.

[0043] In this embodiment, the redistribution layer 100 includes at least one redistribution metal layer 110 and a plurality of first solder pads 120 and second solder pads 130. The redistribution metal layer 110 is used to rewire the fan-out packaging structure. The first solder pads 120 located on the first surface of the redistribution layer 100 are used to electrically connect to the chip structure 200 and the stacked antenna structure 300. The second solder pads 130 located on the second surface of the redistribution layer 100 have solder balls formed on their surfaces, and the embedded antenna chip packaging structure is installed on a printed circuit board using the solder balls.

[0044] In this embodiment, the rewiring layer 100 also has an antenna signal receiving structure (not shown), which is connected to the rewiring metal layer 110 and corresponds to the packaging position of the antenna device. It is used to receive and send signals corresponding to the antenna device 320 and is electrically connected to the chip structure 200 through the rewiring metal layer 110, thereby realizing electrical connection between the chip structure 200 and the antenna device 320 of the stacked antenna structure.

[0045] In other embodiments, there is no antenna signal receiving structure in the redistribution layer, but a conductive through-hole structure is provided in the distance control layer, one end of the conductive through-hole structure is connected to the antenna device, and the other end is connected to the first solder pad on the first surface of the redistribution layer, so that the antenna device is electrically connected to the redistribution metal layer, thereby realizing electrical connection between the antenna device of the chip structure and the stacked antenna structure.

[0046] In this embodiment, the antenna reflection layer corresponding to the antenna device is not provided in the rewiring layer 100. In other embodiments, the antenna reflection layer may be formed in the rewiring layer directly opposite to the antenna device, or in the printed circuit board directly opposite to the embedded antenna chip packaging structure. In some specific chip design solutions, the antenna reflection layer may not be formed.

[0047] In this embodiment, the chip structure 200 is arranged on one side of the embedded antenna chip package structure. In other embodiments, the chip structure can also be arranged in the middle of the embedded antenna chip package structure. However, since the size of the antenna structure in the package structure is often larger than the size of the chip structure, the present invention adjusts the antenna structure to a laminated antenna structure and adjusts the Young's modulus of different layers in the laminated antenna structure to change the stress of the antenna structure, thereby improving the warping problem of the chip package structure as a whole.

[0048] The antenna device 320 of the stacked antenna structure 300 can use different frequencies and different types of antennas. For example, the frequency corresponding to the antenna device is 28 GHz, 39 GHz, 60 GHz or 79 GHz. In order to ensure the performance of the antenna structure, there needs to be a certain distance between the antenna devices of different frequencies and the redistribution layer and the printed circuit board. Therefore, the embodiment of the present invention sets distance control layers of different thicknesses between the antenna device and the redistribution layer, and the thickness of the distance control layers corresponding to antennas of different frequencies are different.

[0049] In this embodiment, the chip structure 200 selects a suitable chip type according to specific design requirements. In a package structure, there may be one chip structure, or multiple chip structures may be packaged at the same time.

[0050] In this embodiment, the laminated antenna structure 300 selects a suitable antenna type according to specific design requirements. In one packaging structure, there may be one laminated antenna structure, or multiple laminated antenna structures may be packaged at the same time. In the same packaging structure, multiple laminated antenna structures may be antennas of the same frequency or antennas of different frequencies.

[0051] When different frequency antennas have different thicknesses of distance control layers, and different antenna devices have different first spacings between the surface close to the protection layer and the first surface of the redistribution layer, the corresponding thicknesses of the protection layers may be the same or different. Researchers may adjust the thickness of the protection layer according to different chip antenna types, chip antenna positions, and edge distances.

[0052] In this embodiment, the first distance between the surface of the antenna device 320 close to the protective layer 330 and the first surface of the redistribution layer 100 is greater than the second distance between the back of the chip structure 200 and the first surface of the redistribution layer 100, and the distance between the surface of the antenna device 320 close to the protective layer 330 and the back of the chip structure 200 is greater than 1 μm. Since there is a certain distance between the surface of the antenna device close to the protective layer and the back of the chip structure, a protective layer with a high Young's modulus formed on the surface of the antenna device can better suppress the warping effect of the embedded antenna chip packaging structure. And for different packaging structures and chip structures, R&D personnel can adjust the anti-warping effect by adjusting different distance control layers, the thickness of the protective layer, and adjusting the distance between the surface of the antenna device close to the protective layer and the back of the chip structure.

[0053] In this embodiment, the distance control layer 310 and the protective layer 330 are made of different materials, and the Young's modulus of the protective layer is higher than that of the distance control layer. Since the Young's modulus of the protective layer is higher than that of the distance control layer, the protective layer can suppress the reverse warping of the antenna packaging structure, thereby effectively preventing the entire embedded antenna chip packaging structure from warping and reducing the reliability of the chip.

[0054] In this embodiment, a material with low dielectric loss Df is used as the distance control layer and the protective layer, so that the distance control layer and the protective layer located on both sides of the antenna device can both protect the antenna device to the maximum extent and reduce the transmission loss of the antenna signal, so that the antenna device can exert the maximum antenna performance.

[0055] Preferably, materials with high dielectric constant Dk and low dielectric loss Df can be used as distance control layers and protective layers, so that the distance control layers and protective layers located on both sides of the antenna device can not only protect the antenna device to the maximum extent, but also reduce the transmission loss of the antenna signal, so that the antenna device can exert the maximum antenna performance.

[0056] In this embodiment, the material of the distance control layer 310 is a packaging resin material, such as epoxy resin, polyimide, benzocyclobutene, polybenzoxazine, etc., and the packaging resin material of the distance control layer 310 can be the same as or different from the material of the plastic package structure 400. The protective layer 330 is a glass substrate with a dielectric loss Df less than 0.01 and a dielectric constant Dk greater than 5. In other embodiments, the protective layer can also be a semiconductor substrate such as a silicon substrate, a silicon carbide substrate, or a ceramic substrate.

[0057] In other embodiments, the distance control layer and the protective layer may also be made of other suitable materials.

[0058] In other embodiments, a stress buffer layer is further formed between the distance control layer and the protective layer, and the stress buffer layer at least wraps the side surface of the antenna device and / or the surface of the antenna device close to the distance control layer. The stress buffer layer disperses the thermal stress caused by the difference in thermal expansion coefficient between the protective layer and the distance control layer, thereby alleviating the stress between the protective layer and the distance control layer, and the stress buffer layer is beneficial to promoting the bonding between the protective layer and the distance control layer. The stress buffer layer can be made of non-metallic materials, such as organic materials and inorganic materials, organic materials such as polyimide (PI), epoxy resin, acrylic acid, molding compounds, etc., inorganic materials such as oxides (SiOx, SiNx, TaOx), glass, silicon, ceramics, etc.

[0059] In this embodiment, the distance control layer 310 and the protection layer 330 in the laminated antenna structure 300 have the same size and area, are aligned up and down, and are formed by the same packaging and cutting process.

[0060] For other embodiments, please refer to Figure 3 , the size and area of ​​the protective layer 330 may also be larger than the size and area of ​​the distance control layer 310. Since the Young's modulus of the protective layer 330 is higher, a larger protective layer can better suppress the warping of the embedded antenna chip packaging structure. Of course, since the Young's modulus of the protective layer 330 is higher, in other specific design schemes, the size and area of ​​the protective layer may also be smaller than the size and area of ​​the distance control layer. By appropriately adjusting the thickness of the protective layer, the effect of suppressing the warping of the embedded antenna chip packaging structure can also be achieved.

[0061] In other embodiments, in order to further reduce the transmission loss of the antenna signal and enable the antenna device to exert the maximum antenna performance, the distance control layer and / or the protective layer is a heterojunction cavity structure, and the heterojunction cavity structure includes a heterojunction center part and a heterojunction edge part at its edge, and the heterojunction center part is opposite to the antenna device, and the dielectric loss of the heterojunction center part is lower than that of the heterojunction edge part.

[0062] For details, please refer to Figure 4 The distance control layer 310 is a first heterojunction cavity structure, including a first heterojunction central part 311 and a first heterojunction edge part 312 at its edge, the first heterojunction central part 311 is opposite to the antenna device 320, the first heterojunction central part 311 and the first heterojunction edge part 312 are made of different materials, and the first heterojunction central part 311 has lower dielectric loss than the first heterojunction edge part 312.

[0063] In another embodiment, the distance control layer does not have a heterojunction cavity structure, but the protective layer has a second heterojunction cavity structure, including a second heterojunction central portion and a first heterojunction edge portion at its edge, the second heterojunction central portion is opposite to the antenna device, the materials of the second heterojunction central portion and the second heterojunction edge portion are different, and the second heterojunction central portion has lower dielectric loss than the second heterojunction edge portion.

[0064] Through the heterojunction cavity structure, on the one hand, low dielectric loss materials can be used as the central part of the heterojunction facing the antenna device, which can further reduce the transmission loss of the antenna. On the other hand, there is an annular heterojunction interface between the central part of the heterojunction and the edge part of the heterojunction at its edge. The heterojunction interface will constrain the antenna signal waveform and improve the directivity of the antenna device.

[0065] In another embodiment, please refer to Figure 5 The distance control layer 310 is a first heterojunction cavity structure, including a first heterojunction central part 311 and a first heterojunction edge part 312 at its edge, and a first heterojunction interface is provided between the first heterojunction central part and the first heterojunction edge part. The protective layer 330 has a second heterojunction cavity structure, including a second heterojunction central part 331 and a second heterojunction edge part 332 at its edge, and a second heterojunction interface is provided between the second heterojunction central part and the second heterojunction edge part. The size of the first heterojunction central part 311 is larger than that of the second heterojunction central part 331, so that the first heterojunction interface and the second heterojunction interface form an inner horn structure.

[0066] In another embodiment, when the size of the central portion of the first heterojunction is smaller than the size of the central portion of the second heterojunction, the first heterojunction interface and the second heterojunction interface form an external horn structure. Researchers can determine the size of the first heterojunction interface and the second heterojunction interface according to specific packaging requirements and antenna types to meet different requirements of different antennas for antenna signal transmission.

[0067] In another embodiment, please refer to Figure 6 When the distance control layer 310 is a first heterojunction cavity structure, an annular first metal transition layer 313 is provided between the first heterojunction center portion 311 and the first heterojunction edge portion 312. The first metal transition layer 313 can enhance the bonding strength between the first heterojunction center portion 311 and the first heterojunction edge portion 312, and as an annular signal guide layer, it can constrain the waveform of the antenna signal, ensure the maximum radiation in the direction perpendicular to the antenna device, and improve the directivity of the antenna device.

[0068] In other embodiments, when the protective layer has a second heterojunction cavity structure, a second annular metal transition layer may be provided between the central portion of the second heterojunction and the edge portion of the second heterojunction. The sizes of the first metal transition layer and the second metal transition layer may be the same or different. When the sizes of the first metal transition layer and the second metal transition layer are different, an inner horn or outer horn structure is formed, which can meet the different requirements of different antennas for antenna signal transmission.

[0069] Based on the above embedded antenna chip packaging structure, the embodiment of the present invention also provides a method for preparing the embedded antenna chip packaging structure, please refer to Figure 7 ,include:

[0070] Step S100, providing a laminated antenna structure and a chip structure, wherein the laminated antenna structure includes a distance control layer, an antenna device located on a surface of the distance control layer, and a protective layer located on a surface of the antenna device, wherein the thickness of the distance control layer is adapted to the corresponding antenna device, and the Young's modulus of the protective layer is higher than the Young's modulus of the distance control layer;

[0071] Step S200, providing a carrier board, attaching a chip structure and a laminated antenna structure to corresponding positions on the carrier board surface, wherein the front side of the chip structure faces the carrier board surface, and the distance control layer of the laminated antenna structure faces the carrier board surface, and forming a plastic packaging structure on the carrier board surface, wherein the plastic packaging structure performs plastic packaging on the chip structure and the laminated antenna structure;

[0072] Step S300, peeling off the plastic package structure and the carrier board;

[0073] Step S400, forming a redistribution layer on the surface of the plastic package structure that exposes the laminated antenna structure and the chip structure, so as to form an embedded antenna chip packaging structure.

[0074] The method for preparing the laminated antenna structure in step S100 can be found in Figure 8 ,include:

[0075] Step S110, providing a protective layer substrate, and forming an antenna device on a surface of the protective layer substrate;

[0076] Step S120, forming a distance control material layer on the surface of the antenna device and the protective layer substrate;

[0077] Step S130: cutting using a cutting process to form the laminated antenna structure.

[0078] Specifically, execute step S110, please refer to Fig. 9 In the present embodiment, the protective layer substrate 30 is a glass substrate, and the antenna device 320 is formed on the glass substrate. Since the structure and shape of the antenna device 320 vary according to different performance requirements, the process of forming the antenna device 320 is also different, which is not limited here.

[0079] In other embodiments, the protective layer substrate may also be a semiconductor substrate such as a silicon substrate, a silicon carbide substrate, or a ceramic substrate.

[0080] In other embodiments, when the protective layer has a second heterojunction cavity structure, the second heterojunction cavity structure includes a second heterojunction central portion and a second heterojunction edge portion at its edge, please refer to Fig.10Before forming the antenna device, a portion of the thickness of the protective layer material is removed at the position of the protective layer substrate 30 corresponding to the antenna device to form a groove, and the groove is refilled with the third material, and the third material and the protective layer substrate 30 are ground through a grinding process until the surface of the protective layer substrate 30 is exposed, and the groove is filled with the third material 31, and the dielectric loss Df of the third material is lower than the dielectric loss Df of the protective layer material, and the third material 31 in the groove serves as the heterojunction center part of the protective layer formed subsequently.

[0081] In other embodiments, before refilling the third material, a metal transition layer is deposited in the groove, and then the third material is refilled on the surface of the metal transition layer in the groove, and the third material and the protective layer substrate are ground through a grinding process until the surface of the protective layer substrate is exposed, and the groove is filled with the third material, and the third material in the groove serves as the heterojunction center part of the protective layer formed subsequently, so that there is an annular metal transition layer between the heterojunction center part and the heterojunction edge part formed in the end.

[0082] Execute step S120, please refer to Fig.11 In this embodiment, a distance control material layer 10 is formed on the surface of the antenna device 320 and the protective layer substrate 30 .

[0083] In this embodiment, a distance control material layer 10 is formed on the surface of the antenna device 320 and the protective layer substrate 30 by using a lamination or molding process. The material of the distance control material layer 10 is a packaging resin material, such as epoxy resin, polyimide, benzocyclobutene, polybenzophenone, etc., and the packaging resin material of the distance control material layer 10 can be the same as or different from the material of the subsequently formed molding structure. It is also possible to further form the distance control material layer and thin the distance control material layer so that the thickness of the distance control material layer can be controlled within a specific range, and the distance control material layer after thinning is smoother, which is conducive to forming a rewiring layer on the surface of the distance control material layer. Different antenna devices 320 correspond to distance control material layers 10 of different thicknesses.

[0084] In other embodiments, a stress buffer layer is first formed on the surface of the antenna device and the protective layer substrate, and then a distance control material layer is formed on the surface of the stress buffer layer. The stress buffer layer is used to relieve the stress difference between the protective layer and the distance control material layer, and is conducive to promoting the bonding between the protective layer and the control material layer. The stress buffer layer can be made of non-metallic materials, such as organic materials and inorganic materials. Organic materials such as polyimide (PI), epoxy resin, acrylic acid, molding compounds, etc., inorganic materials such as oxides (SiOx, SiNx, TaOx), glass, silicon, ceramics, etc.

[0085] In this embodiment, the distance control material layer is a packaging resin material layer, and does not have a conductive through hole inside for electrically connecting the antenna device and the chip structure. In other embodiments, a conductive through hole may also be formed in the distance control material layer, one end of the conductive through hole is connected to the antenna device, and the other end is exposed on the surface of the distance control material layer for subsequent electrical connection with the redistribution metal layer of the redistribution layer.

[0086] In other embodiments, when the distance control layer is a heterojunction cavity structure, please refer to Fig.12 The specific method for forming the distance control material layer includes: after the distance control material layer is formed on the surface of the antenna device and the protective layer substrate, the distance control material layer at the position directly opposite the antenna device is removed until the antenna device or the stress buffer layer is exposed to form a groove, and the groove is refilled with the second material, and the second material and the distance control material layer are ground by a grinding process until the surface of the distance control material layer is exposed, and the groove is filled with the second material 11, and the second material 11 in the groove serves as the middle part of the heterojunction of the distance control layer formed subsequently, and the dielectric loss Df of the second material is lower than the dielectric loss Df of the distance control material layer.

[0087] In other embodiments, before filling the second material, a metal transition layer is deposited in the groove formed by removing the distance control material layer, and the metal transition layer at the bottom of the groove is removed so that the metal transition layer forms a sidewall of the groove, and then the second material is refilled in the groove, and the second material and the distance control material layer are ground by a grinding process until the surface of the distance control material layer is exposed, and the groove is filled with the second material, and the second material in the groove serves as the heterojunction center part of the distance control layer formed subsequently, and a ring-shaped metal transition layer is formed between the heterojunction center part and the heterojunction edge part.

[0088] Step S130 is executed to form the laminated antenna structure by cutting using a cutting process.

[0089] Please refer to Fig.13 In this embodiment, the distance control material layer and the protective layer substrate are cut according to different sizes of the antenna structure to form a laminated antenna structure, in which the distance control layer and the protective layer have the same size and shape.

[0090] In other embodiments, the distance control material layer and the protective layer substrate may be cut twice, and the size and shape of the distance control layer and the protective layer formed are inconsistent. When the size of the protective layer is larger than the distance control layer, the embedded antenna chip packaging structure can be more effectively suppressed from warping.

[0091] After forming the laminated antenna structure, step S200 is performed. Fig.14 , providing a carrier board 50, laminating the chip structure 200 and the laminated antenna structure 300 at corresponding positions on the surface of the carrier board 50, wherein the front side of the chip structure 200 is opposite to the surface of the carrier board 50, and the distance control layer 310 of the laminated antenna structure 300 is opposite to the surface of the carrier board 50, and forming a plastic packaging structure 400 on the surface of the carrier board 50, and the plastic packaging structure 400 performs plastic packaging on the chip structure 200 and the laminated antenna structure 300.

[0092] In this embodiment, the carrier board 50 is a metal board or a rigid-flex board.

[0093] Step S300 is executed to debond and separate the plastic package structure from the carrier.

[0094] In this embodiment, please refer to Fig.15 , the plastic package structure 400, the chip structure 200, and the laminated antenna structure 300 are peeled off from the carrier 50 by a debonding method. The debonding method may be UV debonding, thermal debonding, or laser debonding. In other embodiments, other processes may also be used to peel off the plastic package structure from the carrier.

[0095] Step S400 is executed to form a redistribution layer 100 on the surface of the plastic package structure 400 that exposes the laminated antenna structure 300 and the chip structure 200, and thin the surface to form an embedded antenna chip packaging structure.

[0096] In this embodiment, please refer to Fig.16 The structure of the redistribution layer includes at least one redistribution metal layer 110 and a plurality of first pads 120 and second pads 130. Since the structure and material of the redistribution layer need to be specifically designed according to the specific parameters of the chip packaging structure, no limitation is made here.

[0097] In this embodiment, after the redistribution layer 100 is formed, the surface of the plastic package structure 400 is thinned until the protective layer 330 of the laminated antenna structure 300 is exposed. When an embedded antenna chip packaging structure includes multiple laminated antenna structures 300, and different laminated antenna structures 300 have different frequencies and corresponding distance control layers 310 with different thicknesses, the total thickness of different laminated antenna structures can be the same by adjusting the thickness of different protective layers, or the protective layer of at least one laminated antenna structure can be exposed, and the surface of the protective layer of the laminated antenna structure with a smaller thickness is still covered with a plastic package structure of a certain thickness.

[0098] In other embodiments, after the chip structure and the laminated antenna structure are packaged with a plastic packaging structure, before the plastic packaging structure is peeled off from the carrier, the surface of the plastic packaging structure may be thinned until the protective layer of the laminated antenna structure is exposed.

[0099] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. An embedded antenna chip packaging structure, characterized in that: include: A redistribution layer, a chip structure and a laminated antenna structure located on the first surface of the redistribution layer, a plastic packaging structure located on the first surface of the redistribution layer and encapsulating the chip structure and the laminated antenna structure, the chip structure and the laminated antenna structure are electrically connected through the redistribution layer, the laminated antenna structure comprises a distance control layer located on the first surface of the redistribution layer, an antenna device located on the surface of the distance control layer, and a protective layer located on the surface of the antenna device, wherein the thickness of the distance control layer is adapted to the corresponding antenna device, and the Young's modulus of the protective layer is higher than that of the distance control layer; the distance control layer and / or the protective layer are heterojunction cavity structures, the heterojunction cavity structure comprises a heterojunction center portion and a heterojunction edge portion at its edge, the heterojunction center portion is directly opposite to the antenna device, the dielectric loss of the heterojunction center portion is lower than that of the heterojunction edge portion, and an annular metal transition layer is provided between the heterojunction center portion and the heterojunction edge portion.

2. The embedded antenna chip packaging structure according to claim 1, characterized in that: The length of the protection layer is greater than or equal to the length of the distance control layer, and the width of the protection layer is greater than or equal to the width of the distance control layer.

3. The embedded antenna chip packaging structure according to claim 1, characterized in that: A stress buffer layer is formed between the distance control layer and the protection layer.

4. The embedded antenna chip packaging structure according to claim 1, characterized in that: The material of the distance control layer is different from that of the protective layer, and the dielectric loss of the distance control layer and the protective layer is less than or equal to that of the plastic packaging structure.

5. The embedded antenna chip packaging structure according to claim 1, characterized in that: A first distance between a surface of the antenna device close to the protection layer and the first surface of the redistribution layer is greater than a second distance between a back surface of the chip structure and the first surface of the redistribution layer.

6. The embedded antenna chip packaging structure according to claim 1, characterized in that: When the distance control layer and the protective layer are both heterojunction cavity structures, the sizes of the heterojunction center part of the distance control layer and the heterojunction center part of the protective layer are different, and the heterojunction interface of the distance control layer and the heterojunction interface of the protective layer form an inner horn or outer horn structure.

7. A method for preparing an embedded antenna chip packaging structure, characterized in that: include: Provided are a laminated antenna structure and a chip structure, wherein the laminated antenna structure comprises a distance control layer, an antenna device located on a surface of the distance control layer, and a protective layer located on a surface of the antenna device, wherein the thickness of the distance control layer is adapted to the corresponding antenna device, and the Young's modulus of the protective layer is higher than the Young's modulus of the distance control layer; Providing a carrier board, laminating the chip structure and the laminated antenna structure at corresponding positions on the carrier board surface, wherein the front side of the chip structure faces the carrier board surface, the distance control layer of the laminated antenna structure faces the carrier board surface, and forming a plastic sealing structure on the carrier board surface, wherein the plastic sealing structure performs plastic sealing on the chip structure and the laminated antenna structure; Peeling off the plastic packaging structure from the carrier board; A redistribution layer is formed on the surface of the plastic packaging structure where the laminated antenna structure and the chip structure are exposed; the distance control layer and / or the protective layer is a heterojunction cavity structure, the heterojunction cavity structure includes a heterojunction center part and a heterojunction edge part at its edge, the heterojunction center part faces the antenna device, the dielectric loss of the heterojunction center part is lower than that of the heterojunction edge part, and an annular metal transition layer is provided between the heterojunction center part and the heterojunction edge part.

8. The method for preparing the embedded antenna chip packaging structure according to claim 7, characterized in that: The method for preparing the laminated antenna structure includes: providing a protective layer substrate, forming an antenna device on the surface of the protective layer substrate, forming a distance control material layer on the antenna device and the surface of the protective layer substrate, and cutting using a cutting process to form the laminated antenna structure.

9. The method for preparing the embedded antenna chip packaging structure according to claim 8, characterized in that: Also includes: After the distance control material layer is formed on the surface of the antenna device and the protective layer substrate, the distance control material layer is thinned to reach a set thickness.

10. The method for preparing the embedded antenna chip packaging structure according to claim 8, characterized in that: When cutting is performed using a cutting process, the protective layer and the distance control layer are cut separately, and the size of the protective layer is larger than the size of the distance control layer.

11. The method for preparing the embedded antenna chip packaging structure according to claim 7, characterized in that: When the distance control layer is a heterojunction cavity structure, the specific method for forming the distance control material layer includes: after the distance control material layer is formed on the surface of the antenna device and the protective layer substrate, the distance control material layer at the position directly opposite the antenna device is removed and refilled with a second material, and the filled second material serves as the heterojunction center part of the distance control layer formed subsequently.

12. The method for preparing the embedded antenna chip packaging structure according to claim 11, characterized in that: Before refilling the second material, a metal transition layer is formed on the sidewall of the groove formed by removing the distance control material layer, and then the second material is refilled in the groove, so that an annular metal transition layer is provided between the central part and the edge part of the heterojunction finally formed.

13. The method for preparing the embedded antenna chip packaging structure according to claim 7, characterized in that: When the protective layer is a heterojunction cavity structure, a specific method for forming the protective layer includes: providing a protective layer substrate, removing a portion of the thickness of the protective layer material at a position of the protective layer substrate corresponding to the antenna device to form a refilled third material, and the filled third material serves as the heterojunction center part of the protective layer formed subsequently.

14. The method for preparing the embedded antenna chip packaging structure according to claim 13, characterized in that: Before refilling the third material, a metal transition layer is deposited on the sidewall of the groove formed by removing part of the thickness of the protective layer material, and then the third material is refilled in the groove, so that a ring-shaped metal transition layer is provided between the central part and the edge part of the heterojunction finally formed.

15. The method for preparing the embedded antenna chip packaging structure according to claim 7, characterized in that: When the distance control layer and the protective layer are both heterojunction cavity structures, the sizes of the heterojunction center part of the distance control layer and the heterojunction center part of the protective layer are different, and the heterojunction interface of the distance control layer and the heterojunction interface of the protective layer form an inner horn or outer horn structure.

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