Radio frequency module, manufacturing method and electronic equipment

Abstract

The present invention discloses a radio frequency module, a manufacturing method, and an electronic device, comprising: a substrate wafer; a micro-coaxial structure located on the substrate wafer; a radio frequency chip flip-chip mounted on the micro-coaxial structure; sidewalls located on the substrate wafer and arranged around the micro-coaxial structure; and a cover wafer bonded to the substrate wafer via the sidewalls. The cover wafer is provided with through-silicon vias (TSVs) and signal ports connected to the TSVs, and the TSVs are connected to the micro-coaxial structure via conductive posts. The radio frequency module not only meets high-frequency communication requirements but also has high airtightness, thereby improving radio frequency performance and effectively protecting internal components.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a radio frequency module, a manufacturing method and an electronic device. Background Art

[0002] Electronic communication modules are increasingly moving towards miniaturization and integration. The integration of RF functional modules faces challenges in reducing signal transmission loss, increasing signal isolation, suppressing signal phase distortion, and preventing mutual interference for higher-frequency electromagnetic waves, particularly in the millimeter-wave and terahertz bands.

[0003] Existing technologies employ methods such as fabricating micro-coaxial transmission lines on semiconductor wafers and connecting them to high-frequency devices to form integrated RF functional modules. These modules transmit high-frequency signals and expand in two dimensions to form electronic systems. While these technologies have initially achieved the integration of high-frequency signal transmission between RF devices, since the connection and integration are limited to two dimensions, interfaces with external systems (such as PCBs) still require traditional gold bonding wires and SMA connectors. This results in suboptimal RF performance (gold bonding wires have poor RF performance) and integration (SMA connectors cannot be integrated and manufactured). Summary of the Invention

[0004] The embodiments of the present application provide a radio frequency module, a manufacturing method, and an electronic device. The radio frequency module can not only meet high-frequency communication requirements but also have high airtightness, thereby not only improving the radio frequency performance but also effectively protecting internal components.

[0005] In a first aspect, the present invention provides the following technical solutions through an embodiment of the present invention:

[0006] A radio frequency module comprises: a substrate wafer; a micro-coaxial structure located on the substrate wafer, and a radio frequency chip flip-chip mounted on the micro-coaxial structure; sidewalls located on the substrate wafer and arranged around the micro-coaxial structure; a cover wafer bonded to the substrate wafer via the sidewalls, the cover wafer being provided with through-silicon vias and signal ports connected to the through-silicon vias, and the through-silicon vias being connected to the micro-coaxial structure via conductive columns.

[0007] Preferably, leads are also provided on the substrate wafer, the RF chip is flip-chip mounted on the micro-coaxial structure and the leads, the first port of the RF chip is connected to the port of the micro-coaxial structure, and the second port of the RF chip is connected to the leads, and the cover wafer is provided with a first through-silicon via, a second through-silicon via, a first signal port connected to the first through-silicon via, and a second signal port connected to the second through-silicon via; the port of the micro-coaxial structure is connected to the first through-silicon via through a first conductor post, and the lead is connected to the second through-silicon via through a second conductor post.

[0008] Preferably, the through silicon via includes: a through hole and an annular hole surrounding the through hole; the position of the through hole on the cover wafer corresponds to the position of the conductor column, and is used for signal transmission with the RF chip; the position of the annular hole on the cover wafer corresponds to the outer conductor part of the micro-coaxial structure, and is used for grounding the micro-coaxial structure.

[0009] Preferably, the silicon through hole includes: a first through hole and a third through hole; the position of the first through hole on the cover wafer corresponds to the position of the conductor column, and is used for signal transmission with the RF chip; the position of the third through hole on the cover wafer corresponds to the outer conductor of the micro-coaxial structure, and is used for grounding the micro-coaxial structure.

[0010] Preferably, the upper surface of the cover wafer includes a bonding pad structure and metal implant balls.

[0011] In a second aspect, the present invention provides the following technical solution through an embodiment of the present invention:

[0012] A method for manufacturing a radio frequency module, comprising:

[0013] A micro-coaxial structure and side walls surrounding the micro-coaxial structure are formed on a substrate wafer, and a conductor column perpendicular to the substrate wafer is made on the micro-coaxial structure; a radio frequency chip is flipped on the micro-coaxial structure and connected to the port of the micro-coaxial structure; a cover wafer is provided, wherein the cover wafer is provided with a silicon through-via and a signal port connected to the silicon through-via, and the signal port is used for signal transmission with the radio frequency chip; the cover wafer is bonded to the substrate wafer, wherein the silicon through-via is connected to the conductor column after bonding.

[0014] Preferably, bonding the cover wafer to the substrate wafer includes: making through-silicon vias on the cover wafer, and making a metal bonding layer on the lower surface of the cover wafer, the position of the metal bonding layer corresponding to the position of the side wall and the conductor column; and performing wafer-level bonding of the metal bonding layer on the cover wafer to the side wall and the metal conductor column formed on the substrate wafer.

[0015] Preferably, the production of a through silicon via on a cover wafer includes: forming a through hole and an annular hole surrounding the through hole on the cover wafer, wherein the position of the through hole on the cover wafer corresponds to the position of the conductor post; filling the through hole and the annular hole with conductor material respectively to form the through silicon via, wherein the through silicon via includes a through hole conductor and an annular hole conductor, wherein the through hole conductor is used for bonding to the conductor post, and the annular hole conductor is connected to the outer conductor of the micro-coaxial structure for grounding the micro-coaxial structure.

[0016] Preferably, the production of silicon through vias on the cover wafer includes: forming a first through hole and a third through hole on the cover wafer, the position of the first through hole on the cover wafer corresponding to the position of the conductor post, and the position of the third through hole on the cover wafer corresponding to the position of the outer conductor of the micro-coaxial structure; filling the first through hole and the third through hole with conductor material respectively to form the silicon through vias, the silicon through vias including the first silicon through hole and the third silicon through hole, the first silicon through hole being used for bonding to the conductor post, and the third silicon through hole being connected to the outer conductor of the micro-coaxial structure for grounding the micro-coaxial structure.

[0017] In a third aspect, the present invention provides the following technical solution through an embodiment of the present invention:

[0018] An electronic device comprises a radio frequency module as described in any one of the first aspects above.

[0019] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0020] The embodiment of the present invention provides a radio frequency module, a manufacturing method and an electronic device, comprising: a substrate wafer; a micro-coaxial structure located on the substrate wafer, a radio frequency chip flipped on the micro-coaxial structure; a side wall located on the substrate wafer and arranged around the micro-coaxial structure; a cover wafer bonded to the substrate wafer through the side wall, the cover wafer being provided with a through silicon via and a signal port connected to the through silicon via, the through silicon via being connected to the micro-coaxial structure through a conductor column. The present application prepares side walls and conductor columns on the substrate wafer, and bonds the prepared cover wafer to the substrate wafer including the side walls and conductor columns, thereby updating the original two-dimensional integration to a three-dimensional integration. By adopting the method of bonding the substrate wafer and the cover wafer together, a good airtight packaging structure is provided, which can effectively protect the internal devices, and the through silicon vias integrated on the cover wafer can lead the electrical signals of the radio frequency module to the outside of the cover wafer. In addition, the radio frequency chips are connected to the micro-coaxial structure, and the micro-coaxial technology brings good radio frequency transmission characteristics. Therefore, the three-dimensional integration technology of the RF module improves the integration of the RF chip, reduces the transmission loss of the RF signal, and extends the service life of the RF module, which has practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic structural diagram of a radio frequency module provided in an embodiment of the present invention;

[0023] Figure 2 A schematic diagram of a micro-coaxial structure provided by an embodiment of the present invention;

[0024] Figure 3 A schematic cross-sectional view of a micro-coaxial structure provided by an embodiment of the present invention;

[0025] Figure 4 A vertical section view of the micro-coaxial structure AA' provided in an embodiment of the present invention;

[0026] Figure 5 A cross-sectional top view of the micro-coaxial structure BB' provided in an embodiment of the present invention;

[0027] Figure 6 A side view of a three-dimensional RF module from a micro-coaxial vertical section (AA' direction) according to an embodiment of the present invention;

[0028] Figure 7 A top view of a through hole and an annular hole provided in an embodiment of the present invention;

[0029] Figure 8 Another side view of a three-dimensional radio frequency module from a micro-coaxial vertical section (AA' direction) according to an embodiment of the present invention;

[0030] Figure 9 A top view of the first through hole and the third through hole provided in an embodiment of the present invention;

[0031] Figure 10 A side view of a three-dimensional radio frequency module with a cavity including a through hole and an annular hole provided in an embodiment of the present invention;

[0032] Figure 11 A side view of a three-dimensional radio frequency module with a cavity including a first through hole and a third through hole provided in an embodiment of the present invention;

[0033] Figure 12 A schematic diagram of the structure of a radio frequency chip flip-mounted on CU2 according to an embodiment of the present invention;

[0034] Figure 13 A perspective view of the three-dimensional radio frequency module structure provided by an embodiment of the present invention;

[0035] Figure 14 This is a flow chart of a method for manufacturing a radio frequency module provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0036] The embodiments of the present application provide a radio frequency module, a manufacturing method, and an electronic device. The radio frequency module can not only meet high-frequency communication requirements but also have high airtightness, thereby not only improving the radio frequency performance but also effectively protecting internal components.

[0037] The technical solution of the embodiment of the present application is to solve the above technical problems, and the overall idea is as follows:

[0038] A radio frequency module comprises: a substrate wafer; a micro-coaxial structure located on the substrate wafer; a radio frequency chip flip-chip mounted on the micro-coaxial structure; sidewalls located on the substrate wafer and arranged around the micro-coaxial structure; a cover wafer bonded to the substrate wafer via the sidewalls; the cover wafer is provided with through-silicon vias and signal ports connected to the through-silicon vias; the through-silicon vias are connected to the micro-coaxial structure via conductive columns.

[0039] It should be noted that the RF chip mentioned in this application may be a RF power amplifier, a RF low-noise amplifier or a RF switch, etc.

[0040] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0041] In a first aspect, an embodiment of the present invention provides a radio frequency module, specifically, Figure 1 As shown, the RF module includes a substrate wafer 100; a micro-coaxial structure 101 / 102, located on the substrate wafer 100, and an RF chip 200, which is flip-chip mounted on the micro-coaxial structure 101 / 102; a side wall 104, located on the substrate wafer 200 and arranged around the micro-coaxial structure 101 / 102; a cover wafer 300, bonded to the substrate wafer 100 through the side wall 104, and provided with silicon through vias 301 / 302 and signal ports connected to the silicon through vias on the cover wafer 300, and the silicon through vias 301 / 302 are connected to the micro-coaxial structure 101 / 102 through conductor columns 105 / 106.

[0042] Specifically, the manufacturing process may include: forming a micro-coaxial structure 101 / 102 and a side wall 104 surrounding the micro-coaxial structure 101 / 102 on a substrate wafer 100, and manufacturing a conductor column 105 / 106 perpendicular to the substrate wafer 100 on the micro-coaxial structure 101 / 102; mounting the RF chip 200 on the micro-coaxial structure 101 / 102 through the existing flip-chip technology, and connecting it to the port of the micro-coaxial structure 101 / 102; providing a cover wafer 300, in which silicon through vias 301 / 302 and a signal port connected to the silicon through via are provided, and the signal port is used for signal transmission with the RF chip; bonding the cover wafer 300 to the substrate wafer 100, wherein the silicon through vias 301 / 302 are connected to the conductor column 105 / 106 after bonding.

[0043] As an optional embodiment, the substrate wafer 100 is further provided with leads 102 (ie Figure 1 101 is a micro-coaxial structure, 102 is a lead), the RF chip 200 is flipped on the micro-coaxial structure 101 and the lead 102, the first port of the RF chip 200 is connected to the port of the micro-coaxial structure 101, and the second port of the RF chip 200 is connected to the lead 102.

[0044] The cover wafer 300 is provided with a first through-silicon via (TSV) 301, a second through-silicon via (TSV) 302, a first signal port connected to the first TSV 101, and a second signal port connected to the second TSV 102. The port of the micro-coaxial structure 101 is connected to the first TSV 301 via a first conductive post 105, and the lead 102 is connected to the second TSV 302 via a second conductive post 106.

[0045] It should be noted that the first signal port connected to the micro-coaxial structure through the first silicon via can be used as the signal input and output port of the RF chip, and the second signal port connected to the lead through the second silicon via can be used as the DC signal port of the RF chip.

[0046] Specifically, the manufacturing process may include: forming a micro-coaxial structure 101, a lead 102, and a sidewall 104 surrounding the micro-coaxial structure 101 and the lead 102 on a substrate wafer 100. Conductor pillars 105 / 106 perpendicular to the substrate wafer are formed on the first ports of the micro-coaxial structure 101 and the lead 102, and the RF chip 200 is flipped onto the micro-coaxial structure 101 and the lead 102, and connected to the port of the micro-coaxial structure 101 and the lead 102. The metal conductor copper pillars 105 / 106 and the sidewall 104 are bonded to a cover wafer provided with through-silicon vias 301 / 302. After bonding, the through-silicon vias 301 / 302 are connected to the conductor pillars 105 / 106.

[0047] thus, Figure 1 101 and 102 shown in the figure can both be micro-coaxial structures, or 101 can be a micro-coaxial structure and 102 can be a lead.

[0048] The micro-coaxial structure mentioned in this application is described in detail below:

[0049] like Figure 2 As shown, a schematic diagram of the micro-coaxial structure mentioned in this application, the structure consists of an outer conductor, a central conductor and a dielectric strip 117 supporting the central conductor. The high-frequency RF signal is transmitted by the central conductor and the outer conductor is grounded. The micro-coaxial structure has the advantages of low transmission loss of high-frequency signals and low signal distortion.

[0050] like Figure 3 , is a cross-sectional view of the basic structure of the micro-coaxial structure, wherein the peripheral conductor, the central conductor and the dielectric strip 117 are produced by a five-time copper electroplating process (also including processes such as photolithography and chemical mechanical polishing). Among them, the dielectric strip is produced between the second copper electroplating and the third copper electroplating to support the central conductor. The space between the central conductor and the peripheral conductor is hollow (it can also be filled with a material with a low dielectric constant). Figure 3 As shown, AA' is a vertical cut of the micro-coaxial centerline, and BB' is a transverse cut of the micro-coaxial centerline.

[0051] Figure 4 It is a vertical side view along the AA' centerline of the basic structure of the micro-coaxial structure. Between the lower layer Cu1 and the upper layer Cu5 of the outer conductor, the dielectric strip 117 supports the center conductor. Figure 5 It is a cross-sectional top view along the BB' centerline of the micro-coaxial basic structure. The center conductor is supported by the dielectric strip 117, which is made on Cu2.

[0052] In the specific implementation process, Figure 6As shown, before forming the micro-coaxial structure, metal conductor leads, and sidewalls surrounding the micro-coaxial structure and metal conductor leads on the substrate wafer, a dielectric passivation layer 108 is formed on the substrate wafer, and an adhesion layer, a barrier layer, and a seed layer are fabricated on the dielectric passivation layer. For example, these materials can be Ti / TiN / Cu or Ta / TaN / Cu. The adhesion layer, barrier layer, and seed layer are shown as 107. Subsequently, processes such as photolithography and electroplating are used to fabricate the outer conductor structure 109 / 114 of the micro-coaxial structure, the port support structure 110 for the inner conductor, the RF signal connection ports 111 / 113 and 115 on the micro-coaxial structure, and the RF signal ground port 103 on the micro-coaxial transmission line perpendicular to the substrate wafer surface.

[0053] like Figure 6 As shown, 112 is a metal copper conductor lead made horizontally on the substrate wafer. While preparing the micro-coaxial structure and the metal conductor lead, a copper sidewall 104 perpendicular to the direction of the substrate wafer is made around the RF chip, the micro-coaxial structure and the metal conductor lead. On the basis of preparing the micro-coaxial structure and the metal conductor lead, a metal conductor column 115 perpendicular to the substrate wafer is made on the first port of the micro-coaxial structure, and a metal conductor column 116 perpendicular to the substrate wafer is made on the first port of the metal conductor lead. After the RF chip 200 is flipped, it is mounted (soldered) on the horizontal lead-out end 111 of the micro-coaxial structure and the port of the metal copper conductor lead 112 through the solder ball 201.

[0054] It should be noted that a dielectric passivation layer 108 is formed between all conductors on the substrate wafer for electrical isolation. For example, the dielectric passivation layer can be made of silicon oxide / silicon nitride / polyimide / SU-8 / BCB and other materials.

[0055] In a specific embodiment, bonding the cover wafer 300 to the substrate wafer 100 may include forming through-silicon vias 301 / 303 / 302 / 304 on the cover wafer 300, and forming a metal bonding layer 308 on the lower surface of the cover wafer 300, wherein the position of the metal bonding layer 308 corresponds to the position of the spacers 104, the conductor posts 115, and the conductor posts 116. Wafer-level bonding is then performed on the metal bonding layer 308 on the cover wafer 300 to the spacers 104, the conductor posts 115, and the conductor posts 116 formed on the substrate wafer 100.

[0056] Specifically, the substrate wafer and the cover wafer are bonded, with the bonding position being the metal bonding layer structure and the vertical copper pillars and copper sidewalls. The metal bonding layer structure can be a solder material such as titanium, nickel, tin, silver, or copper, and the metal bonding layer can be produced using a process such as electroplating.

[0057] As an optional embodiment, the fabrication of a through-silicon via on the cover wafer 300 may include: forming a through-hole 301 and an annular hole 303 surrounding the through-hole on the cover wafer, wherein the position of the through-hole 301 on the cover wafer corresponds to the position of the conductor post 115. Conductive material is filled into the through-hole 301 and the annular hole 303, respectively, to form a through-silicon via. The through-silicon via includes a through-hole conductor (first through-silicon via) 301 and an annular hole conductor (annular hole) 303. The through-hole conductor 301 is used for bonding to the conductor post 115, and the annular hole conductor 303 is connected to the outer conductor 109 / 103 of the micro-coaxial structure to ground the micro-coaxial structure.

[0058] Specifically, the electrical signal generated by the RF chip 200 will be transmitted to the through-hole conductor 301 through the horizontal lead-out port 111 of the micro-coaxial structure, the center conductor, and the conductor column 115, and then transmitted to the outside of the cover wafer. The ground end of the micro-coaxial structure is transmitted to the annular hole conductor 303 through the outer conductor 109 / 103 for grounding. Figure 7 , which is a top view of the through hole 301 and the annular hole 303 .

[0059] Furthermore, the fabrication of TSVs on the cover wafer 300 further includes forming a second through-hole 302 and a fourth through-hole 304 on the cover wafer, wherein the position of the second through-hole 302 on the cover wafer corresponds to the position of the conductor post 116. The second through-hole 302 and the fourth through-hole 304 are filled with a conductive material to form TSVs. The TSVs include the second TSV 302 and the fourth TSV 304. The second TSV 302 is used for bonding to the conductor post 116, serving as a DC signal port for the RF chip.

[0060] In addition, after the substrate wafer and the cover wafer are bonded, the sidewalls 104 on both sides can be connected to the annular hole 303 and the fourth silicon through-via 304 respectively, so that the sidewalls and the micro coaxial are at the same level. Figure 8 The left sidewall spacer 104 shown will be connected to the annular hole 303 , and the right sidewall spacer 104 will be connected to the fourth through-silicon via 304 .

[0061] In particular, after making the aforementioned through silicon vias, the process of making the cover wafer also includes: forming a dielectric passivation layer 306 on the lower surface of the cover wafer 300, then making a patterned adhesion layer, a barrier layer and a seed layer 305, and continuing to use photolithography / electroplating and other process methods to prepare a conductor extension structure 307 and the aforementioned metal bonding layer structure 308.

[0062] Furthermore, in order to facilitate further integration of the three-dimensional RF module, or to cut it into independent modules and integrate it into a larger electronic system, pads or balls can be made on the upper surface of the cover wafer. Figure 7As shown, the pad structure 310 on the upper surface of the cover wafer is a bonding pad structure, and the metal implant ball 311 is a bonding ball. In addition, a dielectric passivation layer 309 is formed below the bonding pad structure to play an electrical isolation role.

[0063] As another optional embodiment, Figure 8 As shown, fabricating TSVs on a cover wafer 300 may further include forming a first through-hole 301 and a third through-hole 303 on the cover wafer. The position of the first through-hole 301 on the cover wafer corresponds to the position of the conductor post, and the position of the third through-hole 303 on the cover wafer corresponds to the position of the outer conductor 103 of the micro-coaxial structure. Conductive material is filled into the first through-hole and the third through-hole to form TSVs. The TSVs include the first TSV 301 and the third TSV 303. The first TSV 301 is used for bonding to the conductor post, and the third TSV 303 is connected to the outer conductor of the micro-coaxial structure for grounding the micro-coaxial structure.

[0064] Specifically, if Figure 9 30 is a top view of the first through-silicon via and the third through-silicon via, wherein the first through-silicon via 301 is connected to the central conductor of the micro-coaxial structure for transmitting radio frequency signals, and the third through-silicon via 303 is connected to the outer conductor structure 103 / 109 of the micro-coaxial structure for grounding.

[0065] It should be noted that the structure of only cylindrical metal copper conductor TSV (ie, including the first TSV and the third TSV) is relatively simple to implement and is more suitable for lower frequency RF signal applications.

[0066] Furthermore, in order to facilitate the setting of RF chips of various structures and thicknesses, a cavity can be present between the cover wafer and the RF signal of the substrate wafer. Specifically, the cover wafer is deformed, that is, the thickness of the cover wafer relative to the RF signal is set to be narrower, so that after the substrate wafer and the cover wafer are bonded, a certain cavity is formed between the cover wafer and the RF chip. Figure 10 As shown in FIG, it is a deformation of the cover wafer including the first silicon through via and the annular hole. Figure 11 As shown, a variation of the cover wafer including the first through silicon via and the third through silicon via is shown. A cavity structure with a dielectric passivation layer is fabricated under the cover wafer 300 .

[0067] Furthermore, in order to meet various needs in production, the height of the RF chip 200 flip-chip mounted on the micro-coaxial port is adjustable. Specifically, by adjusting the height of the micro-coaxial port and the lead port, the height of the relative position of the RF chip on the substrate wafer can be adjusted. Specifically, the RF chip can be flip-chip mounted at the position height of CU1, CU2 or CU3. For example, Figure 11 As shown, the RF chip is flip-chip mounted at the height of CU1.

[0068] Furthermore, in order to prevent the metal bonding layer structure (for example, tin material) at the bonding site from producing uncontrolled microscopic liquid overflow when melting at high temperature during the bonding process between the substrate wafer and the cover wafer, thereby causing a short circuit between the metal conductor structures. Therefore, at the location of the metal bonding layer structure, an existing overflow limiting structure for collecting trace amounts of tin liquid can be used. This structure can prevent the overflow of molten tin liquid during the bonding process between the substrate wafer and the cover wafer, and can effectively solve the short circuit problem caused by tin liquid overflow. Of course, this solder current limiting structure can also be used for the solder bonding of the RF chip flip-chip to the end of the transmission line, such as Figure 11 The solder balls are shown as connecting portions to ports 111 and 112 .

[0069] It should be noted that, in addition to the conventional overflow limiting structure, the dielectric strip 117 can also be used as the overflow limiting structure. Specifically, when flip-mounted at the CU2 position, the RF chip can be flip-mounted on the CU2 through the dielectric strip above the CU2, that is, Figure 12 As shown, the RF chip's port is soldered between two dielectric strips, so that any overflow during soldering is blocked by the dielectric strips, thereby limiting the overflow of tin liquid. For example, the dielectric strips are located at both ends of the solder ball 201 connected to the RF chip to block the overflow, or the dielectric strips surround the solder ball 201, so that the solder ball 201 is within the range of the dielectric strips to block the overflow.

[0070] like Figure 13 As shown, a perspective view of the three-dimensional RF module structure provided by an embodiment of the present application is provided. According to a specific circuit design, micro-coaxial transmission lines and copper conductor lines parallel to the wafer surface are made on the substrate wafer, and the RF chip is flip-chip mounted (welded) on the ports of these micro-coaxials and the ports of the copper conductor lines. At the other end of these micro-coaxial transmission lines and copper conductor lines, metal conductor copper columns are made perpendicular to the direction of the substrate wafer. Copper side walls surrounding other structures such as the micro-coaxial structure and its ports, the metal copper conductor line structure and its ports, and the RF chip are made on the substrate wafer, and the copper side walls are perpendicular to the surface of the substrate wafer.

[0071] A metal bonding layer structure is produced at a specific position on the lower surface of the cover wafer, i.e., a position corresponding to the vertically erected metal conductor copper pillars and copper side walls on the substrate wafer. The substrate wafer containing the RF chip, metal copper conductor wires and copper side walls is then bonded to the cover wafer containing the through-silicon via structure, wire bonding pads and metal bonding layer structure to achieve hermetic packaging and fusion of the substrate wafer and the cover wafer.

[0072] Specifically, if Figure 13As shown, the RF signal input and output port (RF I / O) including the signal port (S) and the ground port (G) provided on the cover wafer is used to excite the RF module (chip); the RF chip is biased and controlled through the DC signal port (DC / Bias) provided on the cover wafer.

[0073] Among them, the silicon via structure of the RF signal port on the cover wafer has two forms. The first is that the middle metal copper through-hole conductor transmits the RF signal (S), and the metal copper ring hole conductor surrounding the metal copper through-hole conductor is grounded (G), marked as RF I / O. The second is that the RF signal port (S) and the ground (G) are both silicon vias with metal copper through-hole conductors, marked as RF I / O*. It should be noted that the DC (DC / Bias) signals on the cover wafer all use the second form of silicon via, that is, there is no peripheral metal copper through-hole conductor, only the metal copper through-hole conductor.

[0074] The present application provides a radio frequency module, which is formed by manufacturing a horizontal micro-coaxial structure and its port, as well as a vertical metal conductor copper column (for vertical structural support or vertical electrical signal lead-out) on the substrate wafer plane, flip-chip welding the radio frequency chip on the micro-coaxial port, and flip-chip welding the non-radio frequency function chip (for operation / control / bias and other functions) on the metal conductor copper lead manufactured horizontally on the substrate wafer plane, thereby forming a radio frequency function unit module. Copper side walls of a certain height are manufactured to completely surround the micro-coaxial structure, radio frequency chip, metal conductor copper column and metal conductor copper lead, and other non-radio frequency function chips. The copper side walls surround the space formed by these chips and metal conductor structure and provide protection for the above structure.

[0075] A cover wafer containing a through-silicon via (TSV) structure is also fabricated, and a metal bonding layer structure is formed at specific locations on the lower surface of the cover wafer. The copper sidewalls and metal conductor copper pillars on the substrate wafer are bonded to the cover wafer with the TSV structure at the wafer level via the metal bonding layer. This achieves electrical connection and structural integration of the two wafers, completing the integration of the 3D RF module. Furthermore, solder pads or implant balls are fabricated on the upper surface of the cover wafer to facilitate further integration of the 3D RF module.

[0076] In summary, the present invention provides a radio frequency module that utilizes three-dimensional radio frequency integration technology, integrating the radio frequency chip, substrate wafer, micro-coaxial structure, sidewalls, cover wafer, and through-silicon vias. This technology addresses the issues of poor radio frequency performance and insufficient manufacturing integration associated with conventional two-dimensional planar expansion. While meeting high-frequency communication requirements, this module also improves its airtightness, effectively protecting internal components and extending its service life.

[0077] In the second aspect, based on the same inventive concept, an embodiment of the present invention provides a method for manufacturing a radio frequency module, specifically, as follows Figure 14 As shown, the manufacturing method includes the following steps S101 to S104.

[0078] Step S101, forming a micro-coaxial structure and a sidewall surrounding the micro-coaxial structure on a substrate wafer, and fabricating a conductor column perpendicular to the substrate wafer on the micro-coaxial structure;

[0079] Step S102, flip-chipping the radio frequency chip onto the micro-coaxial structure and connecting it to the port of the micro-coaxial structure;

[0080] Step S103, providing a cover wafer, wherein the cover wafer is provided with through-silicon vias and signal ports connected to the through-silicon vias, wherein the signal ports are used for signal transmission with the radio frequency chip;

[0081] Step S104 , bonding the cover wafer to the substrate wafer, wherein after bonding, the through silicon vias are connected to the conductor posts.

[0082] It should be noted that the specific implementation process of the above steps S101 to S104 can refer to the corresponding description in the RF module embodiment provided in the above first aspect, and will not be repeated here.

[0083] In an optional embodiment, the cover wafer is bonded to the substrate wafer, including: making through-silicon vias on the cover wafer, and making a metal bonding layer on the lower surface of the cover wafer, the position of the metal bonding layer corresponding to the position of the side walls and the conductor columns; and performing wafer-level bonding of the metal bonding layer on the cover wafer to the side walls and metal conductor columns formed on the substrate wafer.

[0084] In an optional embodiment, a through-silicon via is made on a cover wafer, including: forming a through hole and an annular hole surrounding the through hole on the cover wafer, wherein the position of the through hole on the cover wafer corresponds to the position of the conductor post; filling the through hole and the annular hole with conductor material respectively to form a through-silicon via, wherein the through-silicon via includes a through-hole conductor and an annular hole conductor, wherein the through-hole conductor is used for bonding to the conductor post, and the annular hole conductor is connected to the outer conductor of the micro-coaxial structure for grounding the micro-coaxial structure.

[0085] In an optional embodiment, a through-silicon via is made on a cover wafer, including: forming a first through-hole and a third through-hole on the cover wafer, wherein the position of the first through-hole on the cover wafer corresponds to the position of the conductor post, and the position of the third through-hole on the cover wafer corresponds to the position of the outer conductor of the micro-coaxial structure; filling the first through-hole and the third through-hole with conductor material respectively to form a through-silicon via, wherein the through-silicon via includes a first through-silicon via and a third through-silicon via, wherein the first through-silicon via is used for bonding to the conductor post, and the third through-silicon via is connected to the outer conductor of the micro-coaxial structure for grounding the micro-coaxial structure.

[0086] An embodiment of the present invention provides a method for manufacturing a radio frequency module, the implementation principle and technical effects of which are the same as those of the embodiment of the radio frequency module described in the first aspect above. For the sake of brief description, for matters not mentioned in the method embodiment, reference may be made to the corresponding content in the aforementioned radio frequency module embodiment.

[0087] In a third aspect, based on the same inventive concept, this embodiment provides an electronic device comprising the radio frequency module described in the first aspect. It should be noted that the electronic device may be a mobile phone, watch, etc. equipped with the radio frequency module.

[0088] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0089] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A radio frequency module, characterized in that: include: substrate wafer; A micro-coaxial structure is located on the substrate wafer. A radio frequency chip is flip-chip mounted on the micro-coaxial structure; A sidewall is located on the substrate wafer and is arranged around the micro-coaxial structure; a cover wafer bonded to the substrate wafer via the sidewalls, the cover wafer being provided with through-silicon vias and signal ports connected to the through-silicon vias, the through-silicon vias being connected to the micro-coaxial structure via conductive posts; The substrate wafer is further provided with a lead, the RF chip is flip-mounted on the micro-coaxial structure and the lead, a first port of the RF chip is connected to a port of the micro-coaxial structure, and a second port of the RF chip is connected to the lead, and the cover wafer is provided with a first through-silicon via, a second through-silicon via, a first signal port connected to the first through-silicon via, and a second signal port connected to the second through-silicon via; the port of the micro-coaxial structure is connected to the first through-silicon via via a first conductor post, and the lead is connected to the second through-silicon via via a second conductor post; Among them, the first signal port connected to the first silicon via and the micro coaxial structure serves as the signal input and output port of the RF chip, and the second signal port connected to the second silicon via and the lead serves as the DC signal port of the RF chip.

2. The radio frequency module according to claim 1, wherein: The through silicon via comprises: a through hole and an annular hole surrounding the through hole; The position of the through hole on the cover wafer corresponds to the position of the conductor column, and is used for signal transmission with the RF chip. The position of the annular hole on the cover wafer corresponds to the outer conductor part of the micro-coaxial structure, and is used for grounding the micro-coaxial structure.

3. The radio frequency module according to claim 1, wherein: The through silicon via comprises: a first through hole and a third through hole; The position of the first through hole on the cover wafer corresponds to the position of the conductor column, and is used for signal transmission with the RF chip. The position of the third through hole on the cover wafer corresponds to the outer conductor of the micro-coaxial structure, and is used for grounding the micro-coaxial structure.

4. The module according to claim 1, wherein The upper surface of the cover wafer includes a bonding pad structure and metal planting balls.

5. A method for manufacturing a radio frequency module according to any one of claims 1 to 4, characterized in that: include: forming a micro-coaxial structure and a sidewall surrounding the micro-coaxial structure on a substrate wafer, and fabricating a conductor column perpendicular to the substrate wafer on the micro-coaxial structure; Flip-mounting a radio frequency chip on the micro-coaxial structure and connecting it to a port of the micro-coaxial structure; Providing a cover wafer, wherein the cover wafer is provided with a through-silicon via and a signal port connected to the through-silicon via, wherein the signal port is used for signal transmission with the radio frequency chip; The cover wafer is bonded to the substrate wafer, wherein after bonding, the through silicon via is connected to the conductor post.

6. The method according to claim 5, wherein The step of bonding the cover wafer to the substrate wafer includes: Fabricating through silicon vias on the cover wafer and forming a metal bonding layer on the lower surface of the cover wafer, wherein the position of the metal bonding layer corresponds to the positions of the sidewalls and the conductor posts; The metal bonding layer on the cover wafer is bonded to the sidewalls and metal conductor posts formed on the substrate wafer at the wafer level.

7. The method according to claim 6, wherein The method of forming a through silicon via on a cover wafer includes: forming a through hole and a ring-shaped hole surrounding the through hole on the cover wafer, wherein the position of the through hole on the cover wafer corresponds to the position of the conductor post; Conductor materials are filled in the through hole and the annular hole respectively to form the through silicon via. The through silicon via includes a through hole conductor and an annular hole conductor. The through hole conductor is used to be bonded to the conductor column. The annular hole conductor is connected to the outer conductor of the micro coaxial structure to ground the micro coaxial structure.

8. The method according to claim 6, wherein The method of forming a through silicon via on a cover wafer includes: forming a first through hole and a third through hole on the cover wafer, wherein the position of the first through hole on the cover wafer corresponds to the position of the conductor post, and the position of the third through hole on the cover wafer corresponds to the position of the outer conductor of the micro-coaxial structure; Conductor materials are filled in the first through-hole and the third through-hole respectively to form the through-silicon vias. The through-silicon vias include a first through-silicon via and a third through-silicon via. The first through-silicon via is used for bonding to the conductor post. The third through-silicon via is connected to the outer conductor of the micro-coaxial structure for grounding the micro-coaxial structure.

9. An electronic device, characterized in that: The method comprises the radio frequency module according to any one of claims 1 to 4.

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