High-tolerance vertical interconnect structure for SiP package radio frequency array direct port

Abstract

The application relates to the field of radio frequency microwave technology, and particularly discloses a high-tolerance vertical interconnection structure for a SiP packaged radio frequency array direct connection port, which comprises a substrate, a BGA, a packaging structure, a thermal interface layer and a metal mounting base which are arranged in a stack from top to bottom; a TXV coaxial radio frequency transmission structure is arranged in the packaging structure; a radio frequency transmission line connected with the TXV coaxial radio frequency transmission structure; an elastic contact coaxial radio frequency transmission structure which is in contact with the TXV coaxial radio frequency transmission structure is arranged in the metal mounting base; the other end of the elastic contact coaxial radio frequency transmission structure penetrates through the metal mounting base and is connected with an antenna radio frequency port, a rear-end radio frequency transmitting excitation or a radio frequency receiver port. The application effectively reduces the radio frequency connection links, greatly reduces the insertion loss, increases the return loss, improves the signal transmission performance, and increases the heat dissipation capacity of multiple groups of packaging structures.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of radio frequency microwave technology, and more particularly to a high-tolerance vertical interconnection structure for a SiP packaged radio frequency array direct port. BACKGROUND

[0002] With the rapid development of electronic system technologies such as communication, radar, reconnaissance, and electronic countermeasures, the demand for integrating the radio frequencies of systems such as communication, navigation, reconnaissance, and electronic countermeasures into the same radio frequency aperture is becoming increasingly urgent. Digital multi-beam active phased array antennas, which have the advantages of fast beam scanning, strong anti-interference ability, strong multi-target capability, and large coverage of airspace, have become an important technical means for upgrading the electronic performance of various aircraft platforms. With the improvement of the wideband radio frequency application system capability of active phased array antennas, a large number of radio frequency functions need to be integrated into the active radio frequency channel array, the integrated scale of the circuit is greatly improved, and the heat dissipation of the radio frequency transceiver component array power amplifier and other heat generating devices is greatly increased, resulting in a significant increase in the volume and weight of the radio frequency phased array antenna, making it increasingly difficult to solve the problem of heat dissipation.

[0003] Silicon-based, glass-based MEMS, or ceramic radio frequency SiP (System in Package) technology integrates different functional bare chips into the package, has short radio frequency input and output connection paths, good radio frequency performance, high integration density, and low cost, and has unique advantages in the field of radio frequency circuit integration, becoming a hotspot for radio frequency microwave and millimeter wave circuit integration. However, with the increase of the transmission power of the radio frequency transceiver front end, heat dissipation becomes a key problem that needs to be solved for SiP packaging. On the other hand, the increase of the transmission power causes the increase of the power consumption of the power supply, and the importance of transmission efficiency is particularly prominent. The loss of the output port of the transceiver component will directly affect the transmission efficiency of the active array. For every 0.1 dB of loss in the connection of the power output port, the transmission efficiency is lost by about 1 percent. Therefore, the traditional method of attaching a radio frequency SiP to a multi-layer printed board and then realizing radio frequency connection from the radio frequency transceiver component array to the antenna radiation array through multi-layer printed board interconnection increases the length of the radio frequency signal connection path and the number of conversion links. At the same time, the multi-layer board increases the thermal resistance from the package to the antenna radiation surface or metal heat sink, which has a negative impact on the heat dissipation of the radio frequency transceiver front end, and it is difficult to meet the heat dissipation requirements of high-power radio frequency transceiver front ends.

[0004] Directly connecting the pads on the surface of the package to the radio frequency ports of the antenna eliminates the intermediate transition connection link through the multi-layer substrate, and realizes fast horizontal and vertical heat diffusion and heat conduction through the direct contact of the thermal interface layer to the metal mounting base, solving the problems of shortest path low loss connection and low thermal resistance contact.

[0005] The radio frequency transceiver component needs a multilayer printed board to provide radio frequency excitation, amplitude and phase control, transceiver control, power supply and other various electrical signals. The radio frequency transceiver component is first attached to the multilayer printed board, and then connected with an antenna radio frequency port. Due to the error of the printed board layout and the error of the metal mounting base interface position, the performance of the package and the radio frequency port of the antenna may be degraded or even short-circuited. Therefore, the tolerance of the position offset error of the package interface in the two-dimensional direction needs to be greatly improved. SUMMARY

[0006] The technical problem to be solved by the present application is to provide a high-tolerance vertical interconnection structure for a SiP package radio frequency array direct connection port. When the radio frequency signal input and output of one or more groups of radio frequency SiP packages in a super wide working frequency range are connected with multiple groups of radio frequency ports on an external two-dimensional plane, the radio frequency connection link is reduced, the insertion loss is greatly reduced, the return loss is increased, the signal transmission performance is improved, and the heat dissipation capacity of the multiple groups of packages is increased.

[0007] The solution adopted by the present application to solve the technical problem is:

[0008] A high-tolerance vertical interconnection structure for a SiP package radio frequency array direct connection port, comprising a substrate, a BGA, a package structure, a thermal interface layer and a metal mounting base which are stacked from top to bottom.

[0009] A TXV coaxial radio frequency transmission structure is arranged in the package structure, and a radio frequency transmission line connected with the TXV coaxial radio frequency transmission structure.

[0010] An elastic contact coaxial radio frequency transmission structure which is in contact with the TXV coaxial radio frequency transmission structure is arranged in the metal mounting base.

[0011] The other end of the elastic contact coaxial radio frequency transmission structure passes through the metal mounting base and is connected with an antenna radio frequency port, a rear-end radio frequency transmission excitation or a radio frequency receiver port.

[0012] The other end of the TXV coaxial radio frequency transmission structure is welded on the substrate through the BGA.

[0013] In some possible embodiments, the TXV coaxial radio frequency transmission structure is a TGV coaxial radio frequency transmission structure, a TCV coaxial radio frequency transmission structure or a TSV coaxial radio frequency transmission structure.

[0014] The TXV coaxial radio frequency transmission structure and the radio frequency transmission line are connected, and comprise a TXV inner conductor hole and a plurality of TXV outer conductor holes which are arranged outside the TXV inner conductor hole and form a gap between the TXV inner conductor hole.

[0015] In some possible implementation manners, the TXV coaxial-like radio frequency transmission structure further comprises an inner conductor hole pad one arranged at one end of the inner conductor hole of the TXV close to the substrate, an inner conductor hole pad two arranged at one end of the inner conductor hole of the TXV far from the substrate, a ground conductor one arranged at one end of the outer conductor hole of the TXV close to the substrate, and a ground conductor two arranged at one end of the outer conductor hole of the TXV far from the substrate; an inner-outer conductor hole gap one is formed between the ground conductor one and the inner conductor hole pad one, and an inner-outer conductor hole gap two is formed between the ground conductor two and the inner conductor hole pad two; the inner conductor hole of the TXV and the outer conductor hole of the TXV constitute a coaxial-like structure.

[0016] In some possible implementation manners, the elastic contact coaxial-like radio frequency transmission structure comprises an inner conductor column in contact with the inner conductor hole pad two, and a plurality of outer conductor columns surrounding the outer side of the inner conductor column and constituting a coaxial-like structure; the outer conductor columns are in contact with the ground conductor two.

[0017] In some possible implementation manners, the axes of the inner conductor hole of the TXV, the inner conductor column, and the inner conductor hole pad two are parallel to each other or on the same straight line.

[0018] In some possible implementation manners, a hollow region for mounting the inner conductor hole pad two, the inner-outer conductor hole gap two, and the ground conductor two is arranged on the thermal interface layer.

[0019] In some possible implementation manners, the diameter of the inner conductor hole pad two is d 04 , d 04 =d 05 -0.15mm-S 20 .

[0020] In some possible implementation manners, d 05 is the diameter of the circular ring in which the center of the outer conductor hole of the TXV is located, and S 20 is the size of the inner-outer conductor hole gap two, S 20 =0.3mm-0.5mm.

[0021] In some possible implementation manners, the span of the substrate is LK, and LK≤300mm.

[0022] The distance between the inner conductor column and the ground conductor two and the distance between the outer conductor column and the inner conductor hole pad two are both S 21 , S 21 =0.1mm-0.15mm.

[0023] In some possible implementation manners, when LK≤100mm, the distance S 21 between the inner conductor column and the ground conductor two and the distance between the outer conductor column and the inner conductor hole pad two are both 0.1mm.

[0024] When 100mm < LK≤ 300mm, the distance S between the inner conductor post and the ground conductor two, and the outer conductor post and the inner conductor hole pad two 21 are all 0.15mm.

[0025] In some possible embodiments, the packaging structure is a multi-layer structure; comprising a plurality of metal dielectric layers arranged in a stack, and a glass dielectric layer arranged between any two adjacent metal dielectric layers; the metal dielectric layer and the glass dielectric layer above it form a layer of packaging substrate; the TXV coaxial RF transmission structure at least passes through one layer of packaging substrate and is in contact with the elastic contact coaxial RF transmission structure.

[0026] Compared with the prior art, the present application has the following beneficial effects:

[0027] The present application enlarges the diameters of the inner and outer conductor posts of the TGV pad, provides elastic coaxial connection through elastic buttons, and simultaneously presses and sticks a flexible thermal interface layer on the packaging contact surface, thereby solving the problems of multi-group high-power packaging, multi-group or array RF interface connection with antenna radiation units or low-loss back-end connection in large-span size, connection reliability and high-power heat dissipation;

[0028] The present application provides RF connection through the elastic contact of the elastic contact coaxial RF transmission structure, uses the mounting metal mounting base of the RF interface as a low-thermal-resistance heat conduction path, realizes reliable connection of more than 240mm span size and more than 1000 RF ports by enlarging the diameter of the inner conductor hole pad two and the size of the inner and outer conductor hole gap, greatly reduces the loss of the connection of the RF transceiver assembly to the antenna radiation unit, greatly improves the power capacity of the RF transceiver assembly, and improves the tolerance of the RF connection of the SiP packaging of the RF transceiver assembly to the radiation unit to more than ±0.4mm;

[0029] The present application greatly improves the tolerance of the array RF interconnection to the layout, packaging surface, mounting base structure and other errors by enlarging the diameter of the inner conductor hole pad two and the size of the inner and outer conductor hole gap, at the cost of very small RF performance. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is a schematic diagram of the internal structure of the present application;

[0031] Figure 2 It is a top view schematic diagram of the TXV coaxial RF transmission structure and the elastic contact coaxial RF transmission structure of the present application;

[0032] Figure 3 It is a structural schematic diagram of the packaging structure and the TXV coaxial RF transmission structure of the present application;

[0033] Figure 4 It is Figure 2Partial enlarged schematic view;

[0034] Figure 5 Structure schematic diagram of the encapsulation structure, TXV coaxial radio frequency transmission structure in Example 1;

[0035] Figure 6 Structure schematic diagram of the radio frequency transmission line, the first ground conductor, the inner-outer conductor hole gap, the inner conductor hole pad;

[0036] Figure 7 Structure schematic diagram of the second ground conductor, the second inner-outer conductor hole gap, the second inner conductor hole pad;

[0037] Figure 8 Structure schematic diagram of the inner conductor post and the outer conductor post;

[0038] Figure 9 Insertion loss and return loss simulation results of the second inner conductor hole pad with a diameter of 0.3 mm under different second inner-outer conductor hole gaps;

[0039] Figure 10 Insertion loss and return loss simulation results of the second inner conductor hole pad with a diameter of 0.4 mm under different second inner-outer conductor hole gaps;

[0040] Figure 11 Insertion loss and return loss simulation results of the second inner conductor hole pad with a diameter of 0.5 mm under different second inner-outer conductor hole gaps;

[0041] Figure 12 Insertion loss and return loss simulation results of the second inner conductor hole pad with a diameter of 0.6 mm under different second inner-outer conductor hole gaps;

[0042] Figure 13 Insertion loss and return loss simulation results of the second inner conductor hole pad with a diameter of 0.7 mm under different second inner-outer conductor hole gaps;

[0043] Figure 14 Insertion loss and return loss simulation results of the second inner conductor hole pad with a diameter of 0.8 mm under different second inner-outer conductor hole gaps;

[0044] Figures 15-17 Insertion loss and return loss simulation results of the TXV coaxial radio frequency transmission structure and the elastic contact coaxial radio frequency transmission structure under different misalignment sizes;

[0045] Figure 18 Distance schematic diagram between the inner conductor post and the second ground conductor of the elastic contact coaxial radio frequency transmission structure and between the outer conductor post and the second inner conductor hole pad of the elastic contact coaxial radio frequency transmission structure in the application;

[0046] Figure 19A schematic view of a TXV coaxial RF transmission structure, an elastic contact coaxial RF transmission structure tolerating a single direction ±0.5mm and two-dimensional direction ±0.4mm misalignment;

[0047] Wherein: 1, substrate; 2, BGA; 3, packaging structure; 4, thermal interface layer; 5, metal mounting base; A1, TXV coaxial RF transmission structure; T01, TXV inner conductor hole; T02, TXV outer conductor hole; P01, inner conductor hole pad one; P02, inner and outer conductor hole gap one; P03, ground conductor one; P11, pad three; P12, inner and outer conductor hole gap three; P13, ground conductor three; P21, inner conductor hole pad two; P22, inner and outer conductor hole gap two; P23, ground conductor two; A2, elastic contact coaxial RF transmission structure; M01, inner conductor column; M02, outer conductor column; W01, RF transmission line. DETAILED DESCRIPTION

[0048] The application will be described in detail below.

[0049] As Figures 1-19 shown:

[0050] A high-tolerance vertical interconnection structure for SiP packaging RF array direct connection port, comprising a substrate 1, a BGA 2, a packaging structure 3, a thermal interface layer 4, and a metal mounting base 5 stacked from top to bottom;

[0051] A TXV coaxial RF transmission structure A1 is arranged in the packaging structure 3, and a RF transmission line W01 connected with the TXV coaxial RF transmission structure A1;

[0052] An elastic contact coaxial RF transmission structure A2 is arranged in the metal mounting base 5 and in contact with the TXV coaxial RF transmission structure A1;

[0053] The other end of the elastic contact coaxial RF transmission structure A2 passes through the metal mounting base 5 and is connected with an antenna RF port, a back-end RF transmission excitation or a RF receiver port;

[0054] The other end of the TXV coaxial RF transmission structure A1 is welded on the substrate 1 through the BGA 2; the substrate 1 can be a multilayer substrate.

[0055] Specifically, the packaging structure 3 is multiple groups and is installed on the substrate 1 side by side, and the TXV coaxial radio frequency transmission structure A1 is arranged in each group of packaging structure 3; the surface mount of the packaging structure 3 adopts a reflow soldering process, which can be a BGA 2 or other forms of leadless packaging such as QFN packaging; at the same time, the length and width size of the surface mount packaging structure 3 is not limited, and in general, each group of packaging structure 3 should have the same height; if the height difference of the mounted packaging structure 3 is large, the heat dissipation sink of different thickness or the metal mounting base 5 with matching packaging height size of concave-convex shape should be designed according to the height size of the packaging structure 3 and the heat dissipation needs; accordingly, the length of the elastic connection on the metal mounting base 5 should be designed according to the packaging height matching;

[0056] The radio frequency input or output port of the packaging structure 3 adopts the TXV coaxial radio frequency transmission structure A1 and the elastic contact coaxial radio frequency transmission structure A2 in the metal mounting base 5 to rely on elastic contact, and the other end of the elastic contact coaxial radio frequency transmission structure A2 is connected with the antenna radio frequency port, the back-end radio frequency transmission excitation or the radio frequency receiver port; the use of this setting will reduce the radio frequency connection link, greatly reduce the insertion loss, increase the return loss, improve the signal transmission performance, and increase the heat dissipation capacity of the multiple group packaging;

[0057] In some possible embodiments, the TXV coaxial radio frequency transmission structure A1 is a TGV coaxial radio frequency transmission structure, a TCV coaxial radio frequency transmission structure or a TSV coaxial radio frequency transmission structure;

[0058] The TXV coaxial radio frequency transmission structure A1 is connected with the radio frequency transmission line W01, which includes a TXV inner conductor hole T01, a plurality of TXV outer conductor holes T02 surrounding the outside of the TXV inner conductor hole T01 and forming a gap between the TXV inner conductor hole T01, an inner conductor hole pad one P01 arranged at one end of the TXV inner conductor hole T01 close to the substrate 1, an inner conductor hole pad two P21 arranged at one end of the TXV inner conductor hole T01 away from the substrate 1, a ground conductor one P03 arranged at one end of the TXV outer conductor hole T02 close to the substrate 1, and a ground conductor two P23 arranged at one end of the TXV outer conductor hole T02 away from the substrate 1; the gap between the inner and outer conductor holes P02 is formed between the ground conductor one P03 and the inner conductor hole pad one P01, and the gap between the inner and outer conductor holes P22 is formed between the ground conductor two P23 and the inner conductor hole pad two P21; the TXV inner conductor hole T01 and the TXV outer conductor hole T02 constitute a coaxial structure;

[0059] The elastic contact coaxial RF transmission structure A2 includes the inner conductor column M01 in contact with the inner conductor hole pad two P21, and a plurality of groups of outer conductor columns M02 surrounding the outer side of the inner conductor column M01 and constituting a coaxial structure; the outer conductor column M02 is in contact with the ground conductor two P23; specifically, the inner conductor column M01 and the outer conductor column M02 of the elastic contact coaxial RF transmission structure A2 are both elastic elements with a diameter of 0.3mm-0.7mm such as a hair button, a micro spring, and a spring needle.

[0060] The plurality of RF ports on the side surface of the packaging structure 3 close to the metal mounting base 5 are connected to the inner conductor column M01 and the outer conductor column M02 of the elastic contact coaxial RF transmission structure A2 integrated on the metal mounting base 5 through the inner conductor hole pad two P21 and the ground conductor two P23 in a pressure contact manner.

[0061] Further, the inner conductor column M01 is 1 group, and the outer conductor column M02 is 3-9 groups; the inner conductor column M01 and the outer conductor column M02 are isolated and structurally supported by an insulating medium such as polyethylene; the inner conductor column M01 and the outer conductor column M02 are fixed in the insulating medium, and the diameter of the circular ring formed by the plurality of outer conductor columns M02 is determined according to the dielectric constant of the insulating medium, the size and number of the elastic elements, and the simulation results.

[0062] The TXV inner conductor hole T01 is connected to the RF transmission line W01 in the packaging structure 3; the circular ring with the centers of the plurality of TXV outer conductor holes T02 is sleeved outside the TXV inner conductor hole T01 and constitutes a coaxial structure with the TXV inner conductor hole T01, which can realize RF shielding; the TXV outer conductor hole T02 is connected to the ground conductor two P23 and provides insulation isolation between the inner conductor hole pad two P21 and the ground conductor two P23 through the inner and outer conductor hole gap two P22 formed by etching the surface metal; the TXV inner conductor hole T01 and the TXV outer conductor hole T02 can be ceramic vias, silicon vias, or glass vias; the inner conductor hole pad two P21, the inner and outer conductor hole gap two P22, and the ground conductor two P23 form a concentric ring structure;

[0063] In some possible embodiments, the axes of the TXV inner conductor hole T01, the inner conductor column M01, and the inner conductor hole pad two P21 are parallel to each other or on the same straight line;

[0064] The TXV inner conductor hole T01 is not necessarily preset at the center position of the inner conductor hole pad two P21, while the inner conductor column M01 is determined to be preset at the center position of the inner conductor hole pad two P21, only because of the positional deviation caused by the welding position of the packaging structure 3 welded on the substrate 1, the positioning of the substrate 1, and the structural error of the elastic contact coaxial RF transmission structure A2 on the metal mounting base 5.

[0065] In some possible implementations, the thermal interface layer 4 is a flexible thermally conductive pad with a thickness of 0.3 mm to 1 mm in its natural state. A cutout area is provided on the thermal interface layer 4 for mounting the inner conductor hole pad 2P21, the inner and outer conductor hole gap 2P22, and the ground conductor 2P23. That is, except for the inner conductor hole pad 2P21 and the ground conductor 2P23 adjacent to the inner area, the lower surface of the package structure 3 contacts the metal mounting base 5 through the thermal interface layer 4. This arrangement provides a low thermal resistance heat dissipation channel and also buffers the pressure between the package structure 3 and the substrate 1, which is caused by the structural connection between the substrate 1 and the metal mounting base 5.

[0066] In some possible implementations, the diameter of the inner conductor hole pad 2P21 is d. 04 d 04 =d 05 -0.15mm-S 20 ;

[0067] Where, d 05 S is the diameter of the annulus containing the center of the TXV outer conductor hole T02; 20 S represents the dimension of the gap between the inner and outer conductor holes, P22. 20 =0.3mm~0.5mm;

[0068] By adopting the above configuration, the diameter of the inner conductor hole pad P21 and the size of the gap between the inner and outer conductor holes will be effectively increased compared with the prior art, thereby improving the tolerance of the RF port connection of the package structure 3 to manufacturing and installation tolerances.

[0069] In some possible implementations, to achieve higher yield and reliability for direct-connect ports of multiple SiP packaged RF arrays, sufficient distance should be maintained between the inner conductor post M01 and the ground conductor P23, and between the outer conductor post M02 and the inner conductor hole pad P21, in actual use to prevent short circuits. This short-circuit prevention distance needs to be determined based on the total span of the RF port arrays to be interconnected on the multilayer substrate 1. The larger the span, the greater the short-circuit prevention distance should be. Specifically, the span of the substrate 1 is LK, where LK ≤ 300 mm.

[0070] like Figure 18 As shown, the distances between the inner conductor post M01 and the grounding conductor P23, and between the outer conductor post M02 and the inner conductor hole pad P21, are all S. 21 S 21 =0.1mm-0.15mm.

[0071] Furthermore, when LK≤100mm, the distance S between the inner conductor post M01 and the grounding conductor P23, and between the outer conductor post M02 and the inner conductor hole pad P21. 21Both are 0.1mm;

[0072] When 100mm < LK≤ 300mm, the distance S between the inner conductor column M01 and the ground conductor two P23, the outer conductor column M02 and the inner conductor hole pad two P21 21 Both are 0.15mm.

[0073] In some possible embodiments, the packaging structure 3 is a multi-layer structure; comprising a plurality of metal dielectric layers arranged in a stack, and a glass dielectric layer arranged between any two adjacent metal dielectric layers; the metal dielectric layer and the glass dielectric layer above it form a layer of packaging substrate; the TXV coaxial radio frequency transmission structure A1 at least passes through a layer of packaging substrate and is in contact with the elastic contact coaxial radio frequency transmission structure A2.

[0074] In the present application, a plurality of packaging structures 3 are assembled onto the substrate 1 in a BGA2 surface mounting manner, and the plurality of packaging structures 3 and the substrate 1 form an integral whole, and the substrate 1 is screwed to the metal mounting base 5 to realize the structural connection of the radio frequency and the antenna radiation unit;

[0075] The pressure of the screwing structure connection makes the TXV coaxial radio frequency transmission structure A1 in the packaging structure 3 be in close and reliable contact with the radio frequency port (M01-M02) array of the elastic contact coaxial radio frequency transmission structure A2 on the metal mounting base 5 through the radio frequency port (P21-P22-P23) array on the side surface of the packaging structure 3 close to the metal mounting base 5, realizing the direct connection of the plurality of packaging structures 3 to the antenna radiation surface radio frequency port, replacing the connection form of multiple adapters on the adapter substrate 1 in the prior art, shortening the connection path and reducing the connection loss.

[0076] Secondly, the plurality of packaging structures 3 assembled onto the substrate 1 are expanded in diameter of the inner conductor hole pad two P21 and the size of the inner and outer conductor hole gap two P22, based on the low sensitivity of the radio frequency port impedance of the inner conductor hole pad two P21, the inner and outer conductor hole gap two P22, and the ground conductor two P23, the end of the inner conductor column M01 and the end of the outer conductor column M02 have a larger misalignment tolerance size in the two-dimensional plane with the inner conductor hole pad two P21 and the ground conductor two P23 on the side surface of the packaging structure 3 close to the metal mounting base 5, so as not to short circuit, thereby realizing high-reliable radio frequency interconnection of the radio frequency port of the packaging structure 3 with large span size in the two-dimensional plane.

[0077] Thirdly, also by the pressure of the screwing structure connection, the thermal interface layer 4 made of a flexible heat-conducting gasket is in contact with the metal mounting base 5, realizing high-efficiency heat dissipation of the plurality of packaging structures 3.

[0078] The application utilizes the characteristics that the inner conductor hole pad two P21 and the inner-outer conductor hole gap two P22 are low in port impedance sensitivity, expands the diameter of the inner conductor hole pad two P21 and the size of the inner-outer conductor hole gap two P22, and even if the radio frequency port of the elastic contact coaxial radio frequency transmission structure A2 deviates from the center of the inner conductor hole pad two P21 on the radio frequency port contact surface, the radio frequency performance can be guaranteed to be good, thereby guaranteeing the reliability of the radio frequency vertical interconnection of the radio frequency ports (P21-P22-P23) of the multiple groups of packaging structures 3 under a large span size and the radio frequency ports of the elastic contact coaxial radio frequency transmission structure A2 on the metal mounting base 5.

[0079] The center position of the inner conductor column M01 and the inner conductor hole pad two P21 deviates, the diameter of the inner conductor hole pad two P21 and the size of the inner-outer conductor hole gap two P22 are expanded, the distance between the inner conductor column M01 and the outer conductor column M02 can be increased, that is, the diameter of the circular ring formed by the multiple groups of outer conductor columns M02, the tolerance of the packaging structure 3 to the tolerance of the antenna radiation array radio frequency direct connection to the mounting, mechanical installation, processing, etc. can be increased; under the condition that the impedance of the TXV coaxial radio frequency transmission structure A1 and the elastic contact coaxial radio frequency transmission structure A2 is guaranteed to be within the range of ±5% of 50Ω, the radio frequency loss and the transmission standing wave should not change significantly.

[0080] The capacitance of the TXV coaxial radio frequency transmission structure A1 located in the inner-outer conductor hole gap two P22 region of the surface of the packaging structure 3 close to the metal mounting base 5 is determined by the gap width and the air medium, when the diameter of the inner conductor hole pad two P21 and the size of the inner-outer conductor hole gap two P22 are increased, due to the unchanged thickness of the conductor film, the capacitance is slightly increased, and therefore the port impedance changes little, the parameters of the packaging structure 3 radio frequency feedthrough TXV coaxial radio frequency transmission structure A1 and the elastic contact coaxial radio frequency transmission structure A2 on the metal mounting base 5 do not change; therefore, the parasitic capacitance of the TXV coaxial radio frequency transmission structure A1 on the inner conductor hole pad two P21 to the ground conductor two P23 and the outer conductor column M02 on the surface of the packaging structure 3 close to the metal mounting base 5 changes weakly; that is, it is proved that the diameter d 04 of the inner conductor hole pad two P21 and the size of the inner-outer conductor hole gap two P22 have little effect on the radio frequency performance.

[0081] Embodiment 1:

[0082] As shown in Figure 1 , Figure 5 , a high-tolerance vertical interconnection structure for a SiP packaging radio frequency array direct connection port is provided, wherein the TXV coaxial radio frequency transmission structure A1 adopts a TGV coaxial radio frequency transmission structure, the elastic contact coaxial radio frequency transmission structure A2 adopts a hair button coaxial radio frequency transmission structure, and the two form a transition structure in cooperation.

[0083] Specifically, such as Figure 5 As shown, the packaging structure 3 is a four-layer stacked glass-based MEMS packaging structure. The glass-based MEMS packaging structure includes multiple metal dielectric layers and multiple glass dielectric layers. The glass dielectric layers are located between two adjacent metal dielectric layers. The multiple metal dielectric layers are J30, J31, J32, J33, and J34 from top to bottom. J30 and J34 are located on the upper and lower surfaces of the packaging structure 3, respectively. J32 is the signal layer inside the packaging structure 3, which is provided with radio frequency transmission line WO1. The multiple glass dielectric layers are L30, L31, L32, and L33 from top to bottom. In this embodiment, the TXV-type coaxial radio frequency transmission structure A1 will pass through two packaging substrates. To this end, pads three P11, ground conductors three P13, and inner and outer conductor hole gaps three P12 will be added.

[0084] The TXV inner conductor hole T01 and the TXV outer conductor hole T02 pass through the glass dielectric layer L32 and the glass dielectric layer L33 in sequence. The inner conductor hole pad 2 P21 and the ground conductor 2 P23 are located on the lower surface of the package structure 3. The tops of the inner conductor post M01 and the outer conductor post M02 are in contact with the inner conductor hole pad 2 P21 and the ground conductor 2 P23, respectively.

[0085] The glass dielectric layer is alkali-free glass dielectric AF32 with a relative permittivity of 5.1 and a loss factor of 0.0035. Each glass substrate layer is 300 μm thick. The gap s between the RF transmission line W01 and the metal dielectric layer J32 is... 01 The width of the RF transmission line W01 is 80μm, and the RF transmission line W01 is 50μm. The RF transmission line W01 is connected to the TXV inner conductor hole T01. The TXV inner conductor hole T01 passes through the glass dielectric layer L32 and is connected to the pad three P11 on the metal layer J33. The TXV inner conductor hole T01 then passes through the glass dielectric layer L33 and is connected to the inner conductor hole pad two P21 on the lower surface of the package structure 3. The other end of the TXV inner conductor hole T01 is connected to the inner conductor hole pad one P01 on the metal dielectric layer J32.

[0086] Seven TXV external conductor holes T02 penetrating the glass dielectric layer L32 and eight TXV external conductor holes T02 penetrating the glass dielectric layer L33 are designed on the glass dielectric layer L32 to serve as the external conductor structure of the TGV-type coaxial radio frequency transmission structure; one group of the eight TXV external conductor holes T02 penetrating the glass dielectric layer L33 is blocked by the radio frequency transmission line W01 and cannot pass through, so there are only seven TXV external conductor holes T02 penetrating the glass dielectric layer L32.

[0087] The ground plane of the radio frequency transmission line W01 is connected with the ground conductor P03 of the TGV coaxial radio frequency transmission structure, the 7 TXV outer conductor holes T02 pass through the glass medium layer L32 and are connected to the ground conductor three P13 of the metal medium layer J33, and the 8 TXV outer conductor holes T02 pass through the glass medium layer L33 and are connected to the ground conductor two P23 of the packaging surface; all the TXV outer conductor holes T02 are symmetrical relative to the inner conductor hole pad one P01 and are distributed at an isometric angle relative to the center line of the inner conductor hole pad one P01.

[0088] As shown in Figures 6-8 , in the simulation model, the elastic contact coaxial radio frequency transmission structure A2 adopts a 1 hairpin with a diameter d 06 of 0.5 mm as the inner conductor column M01, and 6 hairpins as the outer conductor column M02 to realize the function of the ground shielding column, the outer conductor column M02 is symmetrically distributed relative to the inner conductor column M01, and the center line of the outer conductor column M02 forms a circular ring with a diameter d 07 of 2.05 mm.

[0089] In the simulation modeling, first, the inner conductor column M01 is fixed concentrically with the inner conductor hole pad two P21, and through simulation, the transmission effect of expanding the diameter of the inner conductor hole pad two P21 and the inner-outer conductor hole gap two P22 is verified.

[0090] The simulation model and parameters are shown in Figures 9-14 , the diameter d 04 of the inner conductor hole pad two P21 is set to 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm and 0.8 mm respectively, and different parameters s 20 of the inner-outer conductor hole gap two P22 are set; the results show that the diameter d 04 of the inner conductor hole pad two P21 is less than 0.8 mm, the size s 20 of the inner-outer conductor hole gap two P22 changes from 0.1 mm to 0.5 mm (when the diameter of the inner conductor hole pad two P21 exceeds 0.6 mm, the inner-outer conductor hole gap two P22 cannot reach 0.5 mm due to the limitation of the ground TGV through hole process), the maximum value of the port dB is less than -15 dB; then, the case where the inner-outer conductor hole gap two P22 is 0.1 mm is removed, and the maximum value of the port reflection is less than -20 dB; it can be known that the diameter of the inner conductor hole pad two P21 and the size of the inner-outer conductor hole gap two P22 change in a large range, and will not significantly affect the radio frequency transmission performance of the TGV coaxial-hairpin coaxial transition structure.

[0091] The transmission effects of expanding the diameter of the inner conductor hole pad two P21, the size of the inner and outer conductor hole gap two P22, and the misalignment (or offset) of the center of the inner conductor post M01 and the center of the inner conductor hole pad two P21 are verified through simulation, and the S parameters of the transition structure model are used to characterize the radio frequency transmission performance. Figures 15-17 The simulation results show that expanding the diameter of the inner conductor hole pad two P21 and the size of the inner and outer conductor hole gap two P22 have little effect on the transmission performance; the simulation results show that the misalignment (or offset) of the center of the hairpin coaxial radio frequency transmission structure and the center of the inner conductor hole pad two P21 within ±0.2mm has little effect on the transmission performance, and the position of the inner conductor hole pad two P21 in the present application has a large offset (maximum ±0.2mm), which has little effect on the radio frequency transmission results. At the high end frequency point (13GHz) of the simulated bandwidth, the loss increases from 0.33dB to 0.52dB, and the maximum reflection is close to -28dB.

[0092] The present application can be used for DC-30GHz multi-group non-uniform arrangement SiP packaging or packaging array radio frequency input or output port and simultaneous low loss, high reliability radio frequency interconnection application with multi-group non-uniform arrangement or array radio frequency port; the concentricity deviation of the TXV coaxial radio frequency transmission structure A1 and the elastic contact coaxial radio frequency transmission structure A2 reaches ±0.2mm or more, and under the usual processing and assembly precision (overall position accuracy is less than 0.3%), the radio frequency port of the packaging structure with a transverse span of 90mm can be directly connected from the packaging to the antenna radiation unit or to the back-end local oscillator, radio frequency signal.

[0093] The present application increases the diameter of the inner conductor hole pad two P21 and the size of the inner and outer conductor hole gap two P22, and uses the elastic contact coaxial radio frequency transmission structure A2 which has the longitudinal strain pressure expansion amount, to realize the high reliability radio frequency direct interconnection of the large-scale radio frequency array port based on the packaging surface pad, reduce the connection loss of the radio frequency T / R component, and improve the connection scale and reliability of the active phased array antenna "tile type" radio frequency T / R component. From the simulation results, it can be seen that the insertion loss of a complete TGV coaxial-hairpin coaxial transition structure is less than -0.052dB at 0.8GHz to 13GHz full frequency band, and the reflection is less than -28dB.

[0094] In order to obtain greater port alignment offset tolerance, the diameter d 06The size is 0.63 mm, the outer conductor column M02 diameter is 0.5 mm; the diameter of the circular ring where the center of the plurality of outer conductor columns M02 is located is 2.6 mm; the number of TXV inner hole T01 through holes is increased to 2, the inner conductor hole pad two P21 diameter is increased to 0.8 mm, and the inner and outer conductor hole gap two P22 size is expanded to 1.8 mm; the elastic contact coaxial radio frequency transmission structure A2 and the TXV coaxial radio frequency transmission structure A1 are not short-circuited when the position offset is ±0.5 mm or simultaneously offset in two directions of the two-dimensional plane ±0.4 mm; combined with the simulation results as Figures 9-14 The diameter of the inner conductor hole pad two P21 and the size of the inner and outer conductor hole gap two P22 are increased synchronously, which is more conducive to reducing reflection and obtaining better port performance; therefore, the trend of the diameter of the inner conductor hole pad two P21 and the size of the inner and outer conductor hole gap two P22 changing with the change of the diameter of the inner conductor hole pad two P21 and the size of the inner and outer conductor hole gap two P22 is conducive to obtaining greater tolerance.

[0095] The present application is not limited to the foregoing specific embodiments. The present application extends to any new feature or any new combination disclosed in the specification, and any new method or process steps or any new combination disclosed.

Claims

1. A high-tolerance vertical interconnect structure for direct-connect ports of SiP packaged radio frequency arrays, characterized in that, It includes, from top to bottom, a substrate, a BGA, a package structure, a thermal interface layer, and a metal mounting base; The package structure includes a TXV coaxial radio frequency transmission structure and a radio frequency transmission line connected to the TXV coaxial radio frequency transmission structure. An elastic contact coaxial radio frequency transmission structure that contacts and engages with the TXV type coaxial radio frequency transmission structure is provided in the metal mounting base. The other end of the elastic contact coaxial radio frequency transmission structure passes through the metal mounting base and is connected to the antenna radio frequency port, the rear radio frequency transmission excitation or radio frequency receiver port. The other end of the TXV-type coaxial radio frequency transmission structure is soldered to the substrate via BGA. The TXV type coaxial radio frequency transmission structure is a TGV type coaxial radio frequency transmission structure, a TCV type coaxial radio frequency transmission structure or a TSV type coaxial radio frequency transmission structure. The TXV-like coaxial RF transmission structure is connected to the RF transmission line and includes an inner TXV conductor hole, multiple sets of outer TXV conductor holes surrounding the outer side of the inner TXV conductor hole and forming gaps with the inner TXV conductor hole, an inner conductor hole pad one located at the end of the inner TXV conductor hole near the substrate, an inner conductor hole pad two located at the end of the inner TXV conductor hole away from the substrate, a ground conductor one located at the end of the outer TXV conductor hole near the substrate, and a ground conductor two located at the end of the outer TXV conductor hole away from the substrate; a gap one is formed between the ground conductor one and the inner conductor hole pad one, and a gap two is formed between the ground conductor two and the inner conductor hole pad two; the inner TXV conductor hole and the outer TXV conductor hole constitute a coaxial structure; The elastic contact coaxial radio frequency transmission structure includes an inner conductor post that contacts and engages with the inner conductor hole pad two, and multiple sets of outer conductor posts that surround the outer side of the inner conductor post and form a coaxial structure; the outer conductor post contacts and engages with the ground conductor two. The diameter of the inner conductor hole pad 2 is d. 04 d 04 =d 05 -0.15mm-S 20 ; Where, d 05 S is the diameter of the annulus containing the center of the TXV outer conductor hole; 20 S is the dimension of the gap between the inner and outer conductor holes. 20 =0.3mm~0.5mm.

2. The high-tolerance vertical interconnect structure for direct-connect ports of SiP packaged RF arrays according to claim 1, characterized in that, The axes of the TXV inner conductor hole, inner conductor post, and inner conductor hole pad are parallel to each other or on the same straight line.

3. A high-tolerance vertical interconnect structure for direct-connect ports of SiP packaged RF arrays according to claim 2, characterized in that, A cutout area is provided on the thermal interface layer for mounting the inner conductor hole pad 2, the inner and outer conductor hole gap 2, and the ground conductor 2.

4. The high-tolerance vertical interconnect structure for direct-connect ports of SiP packaged RF arrays according to claim 1, characterized in that, The span of the substrate is LK, where LK ≤ 300 mm; The distances between the inner conductor post and the grounding conductor two, and between the outer conductor post and the inner conductor hole pad two, are all S. 21 S 21 =0.1mm-0.15mm.

5. A high-tolerance vertical interconnect structure for direct-connect ports of SiP packaged RF arrays according to claim 4, characterized in that, When LK≤100mm, the distance S between the inner conductor post and the grounding conductor II, and between the outer conductor post and the inner conductor hole pad II. 21 All are 0.1mm; When 100mm < LK ≤ 300mm, the distance S between the inner conductor post and the grounding conductor II, and between the outer conductor post and the inner conductor hole pad II. 21 All are 0.15mm.

6. A high-tolerance vertical interconnect structure for a direct-connect port of a SiP packaged RF array according to any one of claims 1-5, characterized in that, The packaging structure is a multilayer structure, including multiple stacked metal dielectric layers and a glass dielectric layer disposed between two adjacent metal dielectric layers; the metal dielectric layers and the glass dielectric layer above them form a packaging substrate; the TXV-like coaxial radio frequency transmission structure passes through at least one packaging substrate and is in contact with the elastic contact-like coaxial radio frequency transmission structure.

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