Inductive coupling structure based on gold wire bonding
By adopting an inductive coupling structure with gold wire bonding in the inductive compensation structure, the transmission line vias and microstrip differential transmission lines are separated, and compensation is performed through the gold wire electrical connection, the problem of insufficient insertion loss and return loss during signal transmission in the prior art is solved, and better signal stability and accuracy are achieved.
Patent Information
- Application Number
- CN202421891508.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-05
- Publication Date
- 2025-05-16
- Estimated Expiration
- 2034-08-05
AI Technical Summary
The existing inductance compensation structure has small insertion loss and return loss during signal transmission, which cannot meet the requirements of stability and accuracy of the signal during high-speed transmission.
Using an inductive coupling structure based on gold wire bonding, by separating the transmission line via from the microstrip differential transmission line, the microstrip differential transmission line and the transmission line via are electrically connected to the microstrip differential transmission line and compensate for the parasitic capacitance generated by the transmission line via.
It effectively reduces the insertion loss caused by signal transmission and increases return loss, improves the anti-interference ability of the substrate and inductance compensation effect, and meets the stability and accuracy requirements of the signal during high-speed transmission.
Smart Images
Figure CN222883543U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of microelectronic packaging of chips, and in particular to an inductive coupling structure based on gold wire bonding. Background Art
[0002] At present, modern communications are developing towards multi-channel, high-bandwidth and high-density. In order to arrange transmission lines with more channels in a limited wiring space, most of the related arrangements use alternating microstrip lines and strip lines. However, since strip lines need to use vias to transmit signals, the parasitic capacitance generated by them will seriously affect the impedance matching of the RF link, resulting in impedance discontinuity, thereby causing signal reflection and transmission loss.
[0003] In the related technology, inductance compensation is generally used to reduce signal reflection and transmission loss and improve the signal integrity of the entire transmission line. Figure 1 As shown, in the inductance compensation structure, the microstrip differential transmission line is directly connected to the via, but this connection method reduces the insertion loss and increases the return loss during signal transmission, which cannot meet the requirements of signal stability and accuracy during high-speed transmission.
[0004] Therefore, it is necessary to design a new inductive coupling structure based on gold wire bonding to overcome the above problems. Utility Model Content
[0005] The present application provides an inductive coupling structure based on gold wire bonding, which can solve the technical problem in the related art that the reduced insertion loss and increased return loss of the inductive compensation structure during signal transmission are both small, and cannot meet the requirements of signal stability and accuracy during high-speed transmission.
[0006] In a first aspect, an embodiment of the present application provides an inductive coupling structure based on gold wire bonding, comprising: a substrate, a strip differential transmission line and a microstrip differential transmission line, wherein the substrate is provided with a transmission line via; the strip differential transmission line is fixed to the substrate and electrically connected to one end of the transmission line via; the microstrip differential transmission line is fixed to the substrate, the microstrip differential transmission line is spaced apart from the transmission line via, and the microstrip differential transmission line is electrically connected to the other end of the transmission line via through a gold wire.
[0007] In combination with the first aspect, in one implementation, the substrate includes a plurality of conductive layers and a plurality of dielectric plates, the conductive layers and the dielectric plates are alternately stacked, and the microstrip differential transmission line and the gold wire are located on the dielectric plate at the top layer.
[0008] In combination with the first aspect, in one embodiment, the plurality of conductive layers are arranged as four conductive layers, the plurality of dielectric plates are arranged as a first dielectric plate, a second dielectric plate and a third dielectric plate, the first dielectric plate is located at the bottom of the conductive layer of the top layer, the third dielectric plate is located at the top of the conductive layer of the bottom layer, and the strip differential transmission line is located at the third dielectric plate.
[0009] In combination with the first aspect, in one implementation, the thickness of the first dielectric plate and the third dielectric plate is set to 7.2-8.8 mil, and the thickness of the second dielectric plate is set to 1.8-2.2 mil.
[0010] In combination with the first aspect, in one implementation, the thickness of the conductive layer between the second dielectric plate and the third dielectric plate is set to 0.45-0.55 oz, and the thickness of the other conductive layers is set to 0.9-1.1 oz.
[0011] In combination with the first aspect, in one implementation, the conductive plate is configured as copper foil.
[0012] In combination with the first aspect, in one implementation, the dielectric loss of the dielectric plate is set to 0.00135 to 0.00165.
[0013] In combination with the first aspect, in one implementation, the strip differential transmission line includes two sections of strip single-ended transmission line, and the spacing between the two sections of the strip single-ended transmission line is set to 0.135-0.165 mm.
[0014] In combination with the first aspect, in one implementation, the spacing between the two sections of the microstrip differential transmission line is set to 0.0675-0.0825 mm.
[0015] In combination with the first aspect, in one implementation, the gold wire is arched along the axial direction of the transmission line via, the diameter of the gold wire is set to 22.5-27.5um, and the arch height of the gold wire is set to 22.5-27.5um.
[0016] The beneficial effects brought by the technical solution provided in the embodiments of the present application include:
[0017] In this embodiment, the transmission line vias are separated from the microstrip differential transmission lines, and gold wires are used to electrically connect the microstrip differential transmission lines and the transmission line vias. The parasitic inductance generated by the gold wires in the package can compensate for the parasitic capacitance generated by the transmission line vias, so that the substrate has better anti-interference ability and better compensation effect than the single-ended transmission line, effectively reducing the insertion loss caused by signal transmission and increasing the return loss, thereby solving the technical problem in the related art that the insertion loss reduced and the return loss increased by the inductance compensation structure during the signal transmission process are both small, and the requirements for stability and accuracy of the signal during high-speed transmission cannot be met. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0019] Figure 1 is a structural schematic diagram of an inductive coupling structure in the related art;
[0020] Figure 2 A schematic diagram of a structure of an inductive coupling structure based on gold wire bonding provided in an embodiment of the present application;
[0021] Figure 3 A perspective view of a strip differential transmission line and a transmission line via provided in an embodiment of the present application;
[0022] Figure 4 A side view of a strip differential transmission line and a transmission line via provided in an embodiment of the present application;
[0023] Figure 5 A comparison diagram of insertion loss performance curves of an inductive coupling structure based on gold wire bonding provided in an embodiment of the present application and an inductive coupling structure in related art;
[0024] Figure 6 A comparison chart of return loss performance curves of an inductive coupling structure based on gold wire bonding provided in an embodiment of the present application and an inductive coupling structure in related technologies.
[0025] In the figure: 1. substrate; 11. conductive layer; 12. dielectric plate; 121. first dielectric plate; 122. second dielectric plate; 123. third dielectric plate; 2. transmission line via; 3. strip differential transmission line; 31. strip single-ended transmission line; 4. microstrip differential transmission line; 5. gold wire. DETAILED DESCRIPTION
[0026] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0027] The embodiment of the present application provides an inductive coupling structure based on gold wire bonding, which can solve the technical problem that the reduced insertion loss and increased return loss of the inductive compensation structure during signal transmission are both small, and cannot meet the requirements of signal stability and accuracy during high-speed transmission.
[0028] See also Figure 2 and Figure 3 As shown, an embodiment of the present application provides an inductive coupling structure based on gold wire bonding, which includes: a substrate 1, a strip differential transmission line 3 and a microstrip differential transmission line 4, wherein the substrate 1 is provided with a transmission line via 2; the strip differential transmission line 3 is fixed to the substrate 1 and electrically connected to one end of the transmission line via 2; the microstrip differential transmission line 4 is fixed to the substrate 1, the microstrip differential transmission line 4 is spaced apart from the transmission line via 2, and the microstrip differential transmission line 4 is electrically connected to the other end of the transmission line via 2 through a gold wire 5.
[0029] In this embodiment, the transmission line via 2 is provided in the substrate 1, one end of the transmission line via 2 is electrically connected to the strip differential transmission line 3, and one end of the transmission line via 2 is electrically connected to the microstrip differential transmission line 4 through the gold wire 5. The strip differential transmission line 3 limits the electric field of the strip differential transmission line 3 to the substrate 1, and does not radiate energy and is not interfered by external radiation during the transmission of the differential signal, so that the substrate 1 has anti-interference ability. The parasitic inductance generated by the gold wire 5 in the package can compensate for the parasitic capacitance generated by the transmission line via 2, so that the substrate 1 has an inductance compensation effect. Compared with the single-ended transmission line, the substrate 1 has better anti-interference ability and better compensation effect.
[0030] In this embodiment, the transmission line via 2 is separated from the microstrip differential transmission line 4, and the gold wire 5 is used to electrically connect the microstrip differential transmission line 4 and the transmission line via 2. The parasitic inductance generated by the gold wire 5 in the package can compensate for the parasitic capacitance generated by the transmission line via 2, so that the substrate 1 has better anti-interference ability and better compensation effect than the single-ended transmission line, effectively reduces the insertion loss generated by signal transmission, and increases the return loss. The insertion loss of the substrate 1 is reduced by 0.41dB and the return loss is increased by 4.8dB in the frequency range of 0 to 30GHz through simulation. Figure 5 and Figure 6 As shown, A represents the substrate, B represents Figure 1 The inductive coupling structure in the related art generally reduces the insertion loss by 0.1 to 0.2 dB and increases the return loss by 2 to 3 dB in the frequency range of 0 to 30 GHz, thereby solving the technical problem that the reduced insertion loss and increased return loss of the inductive compensation structure in the related art during signal transmission are both small, and cannot meet the requirements of signal stability and accuracy during high-speed transmission.
[0031] Further, see Figure 2 As shown, in some embodiments, the substrate 1 includes multiple conductive layers 11 and multiple dielectric plates 12, the conductive layers 11 and the dielectric plates 12 are alternately stacked, and the microstrip differential transmission line 4 and the gold wire 5 are located on the topmost dielectric plate 12.
[0032] In this embodiment, the plate model of the dielectric plate 12 can be Rogers1200, and the conductive layer 11 and the dielectric plate 12 are alternately stacked to form the substrate 1, so that the impedance of the substrate 1 can be set at 100Ω while the overall thickness of the substrate 1 is minimized. The thickness of the substrate 1 can be set to 0.587mm, and the topmost conductive layer 11 etches away the material at the location of the microstrip differential transmission line 4 and the transmission line via 2, and the etched periphery of the conductive layer 11 forms a ground wire, and the tops of the microstrip differential transmission line 4, the gold wire 5 and the transmission line via 2 are exposed.
[0033] Further, see Figure 2-4 As shown, in some embodiments, the plurality of conductive layers 11 are set to four conductive layers 11, the plurality of dielectric plates 12 are set to a first dielectric plate 121, a second dielectric plate 122 and a third dielectric plate 123, the first dielectric plate 121 is located at the bottom of the conductive layer 11 of the top layer, the third dielectric plate 123 is located at the top of the conductive layer 11 of the bottom layer, and the strip differential transmission line 3 is located on the third dielectric plate 123.
[0034] In this embodiment, the plurality of conductive layers 11 are set to four conductive layers 11, the plurality of dielectric plates 12 are set to three dielectric plates 12, and the four conductive layers 11 and the three dielectric plates 12 are alternately stacked to form the substrate 1, wherein the strip differential transmission line 3 is located on the third dielectric plate 123, ensuring that the impedance of the substrate 1 is set at 100Ω while the overall thickness of the substrate 1 is minimized, and the second dielectric plate 122 can be set as a reference ground layer of the microstrip differential transmission line 4.
[0035] Further, see Figure 2 As shown, in some embodiments, the thickness of the first dielectric plate 121 and the third dielectric plate 123 is set to 7.2-8.8 mil, and the thickness of the second dielectric plate 122 is set to 1.8-2.2 mil.
[0036] In this embodiment, the thickness of the first dielectric plate 121 and the third dielectric plate 123 can be set to 7.2-8.8 mil, preferably, the thickness of the first dielectric plate 121 and the third dielectric plate 123 is set to 8 mil, and the thickness of the second dielectric plate 122 can be set to 1.8-2.2 mil, preferably, the thickness of the second dielectric plate 122 is set to 2 mil, so that the medium formed by the first dielectric plate 121, the second dielectric plate 122 and the third dielectric plate 123 ensures that the signal line spacing between the strip differential transmission line 3 and the microstrip differential transmission line 4 is closest under the premise that the impedance of the substrate 1 is 100Ω, and can be directly connected through the transmission line via 2.
[0037] Further, see Figure 2 As shown, in some embodiments, the thickness of the conductive layer 11 between the second dielectric plate 122 and the third dielectric plate 123 is set to 0.45-0.55 oz, and the thickness of the other conductive layers 11 is set to 0.9-1.1 oz.
[0038] In this embodiment, the thickness of the conductive layer 11 located between the second dielectric plate 122 and the third dielectric plate 123 can be set to 0.45-0.55 oz. Preferably, the conductive layer 11 located between the second dielectric plate 122 and the third dielectric plate 123 is set to 0.5 oz. The thickness of the other conductive layers 11 can be set to 0.9-1.1 oz. Preferably, the thickness of the other conductive layers 11 is set to 1 oz, so that the impedance of the substrate 1 is maintained at 100 Ω and the overall link impedance matching effect of the substrate 1 is better. Increasing the thickness of the conductive layer 11 will cause the impedance of the substrate 1 to be too small.
[0039] Further, see Figure 2As shown, in some embodiments, the conductive layer 11 is set as copper foil. In this embodiment, the copper foil is the most common PCB conductor material, and the conductive layer 11 is made of copper foil, which ensures that the conductive layer 11 has high conductivity and low cost.
[0040] Further, see Figure 2 As shown, in some embodiments, the dielectric loss of the dielectric plate 12 is set to 0.00135-0.00165. In this embodiment, the dielectric plate 12 is set to a common PCB dielectric material, the dielectric constant of the dielectric plate 12 is 3.05, and the dielectric loss of the dielectric plate 12 can be set to 0.00135-0.00165. Preferably, the dielectric loss of the dielectric plate 12 is set to 0.0015. If the dielectric loss of the dielectric plate 12 is too large, the loss of the RF link will be too large. Reducing the dielectric loss of the dielectric plate 12 will greatly increase the processing cost of the substrate 1.
[0041] Further, see Figure 3 As shown, in some embodiments, the strip differential transmission line 3 includes two sections of strip single-ended transmission lines 31, and the spacing between the two sections of the strip single-ended transmission lines 31 is set to 0.135-0.165mm. In this embodiment, the width of the strip single-ended transmission line 31 can be set to 0.8mm, the spacing between the strip single-ended transmission line 31 and the ground line can be set to 0.09mm, and the spacing between the two sections of the strip single-ended transmission line 31 is set to 0.135-0.165mm. Preferably, the spacing between the two sections of the strip single-ended transmission line 31 is set to 0.15mm, so that the impedance of the substrate 1 is maintained at 100Ω, and the overall link impedance matching effect of the substrate 1 is better. If the spacing between the two sections of the strip single-ended transmission line 31 is too large, the impedance of the substrate 1 will be too large.
[0042] Further, see Figure 2 As shown, in some embodiments, the spacing between the two sections of the microstrip differential transmission line 4 is set to 0.0675-0.0825mm. In this embodiment, the microstrip differential transmission line 4 can be set to a rectangular parallelepiped, the length of the microstrip differential transmission line 4 can be set to 0.4mm, the width of the microstrip differential transmission line 4 can be set to 0.14mm, the spacing between the microstrip differential transmission line 4 and the ground line can be set to 0.15mm, and the spacing between the two sections of the microstrip differential transmission line 4 can be set to 0.0675-0.0825mm. Preferably, the spacing between the two sections of the microstrip differential transmission line 4 is set to 0.075mm, so that the impedance of the substrate 1 is maintained at 100Ω, and the overall link impedance matching effect of the substrate 1 is better. If the spacing between the two sections of the microstrip differential transmission line 4 is too large, the impedance of the substrate 1 will be too large.
[0043] Further, see Figure 3 and Figure 4 As shown, in some embodiments, the gold wire 5 is arched along the axial direction of the transmission line via 2, the diameter of the gold wire 5 is set to 22.5-27.5um, and the arch height of the gold wire 5 is set to 22.5-27.5um.
[0044] In this embodiment, the diameter of the gold wire 5 can be set to 22.5~27.5um. Preferably, the diameter of the gold wire 5 is set to 25um. The diameter of the gold wire 5 is set to the most common diameter in the existing process. If the diameter of the gold wire 5 is too large, the processing cost of the substrate 1 will increase. If the diameter of the gold wire 5 is too small, the overall link loss of the substrate 1 will increase. The length of the gold wire 5 can be set to 200um, the bonding width between the gold wire 5 and the microstrip differential transmission line 4 can be set to 115um, and the arch height of the gold wire 5 can be set to 22.5~27.5um. Preferably, the arch height of the gold wire 5 is set to 25um. If the arch height of the gold wire 5 is too large, the parasitic inductance generated by the differential transmission line structure will be too large. If the arch height of the gold wire 5 is too small, the inductance compensation generated by the differential transmission line structure will be insufficient.
[0045] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.
[0046] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.
[0047] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.
Claims
1. An inductive coupling structure based on gold wire bonding, characterized in that: It includes: A substrate (1), wherein the substrate (1) is provided with a transmission line via (2); A strip differential transmission line (3) is fixedly arranged on the substrate (1) and electrically connected to one end of the transmission line via (2); a microstrip differential transmission line (4) is fixedly arranged on the substrate (1), the microstrip differential transmission line (4) and the transmission line via (2) are arranged at intervals, and the microstrip differential transmission line (4) is electrically connected to the other end of the transmission line via (2) through a gold wire (5).
2. The inductive coupling structure based on gold wire bonding according to claim 1, characterized in that: The substrate (1) comprises a plurality of conductive layers (11) and a plurality of dielectric plates (12), the conductive layers (11) and the dielectric plates (12) being alternately stacked, and the microstrip differential transmission line (4) and the gold wire (5) are located on the dielectric plate (12) at the top layer.
3. The inductive coupling structure based on gold wire bonding according to claim 2, characterized in that: The plurality of conductive layers (11) are arranged as four conductive layers (11); the plurality of dielectric plates (12) are arranged as a first dielectric plate (121), a second dielectric plate (122) and a third dielectric plate (123); the first dielectric plate (121) is located at the bottom of the conductive layer (11) at the top layer; the third dielectric plate (123) is located at the top of the conductive layer (11) at the bottom layer; and the strip differential transmission line (3) is located at the third dielectric plate (123).
4. The inductive coupling structure based on gold wire bonding according to claim 3, characterized in that: The thickness of the first dielectric plate (121) and the third dielectric plate (123) is set to 7.2-8.8 mil, and the thickness of the second dielectric plate (122) is set to 1.8-2.2 mil.
5. The inductive coupling structure based on gold wire bonding according to claim 3, characterized in that: The thickness of the conductive layer (11) between the second dielectric plate (122) and the third dielectric plate (123) is set to 0.45-0.55 oz, and the thickness of the other conductive layers (11) is set to 0.9-1.1 oz.
6. The inductive coupling structure based on gold wire bonding according to claim 2, characterized in that: The conductive layer (11) is provided as copper foil.
7. The inductive coupling structure based on gold wire bonding according to claim 2, characterized in that: The dielectric loss of the dielectric plate (12) is set to 0.00135-0.00165.
8. The inductive coupling structure based on gold wire bonding according to claim 1, characterized in that: The strip-shaped differential transmission line (3) comprises two sections of strip-shaped single-ended transmission lines (31), and the spacing between the two sections of the strip-shaped single-ended transmission lines (31) is set to 0.135-0.165 mm.
9. The inductive coupling structure based on gold wire bonding according to claim 1, characterized in that: The spacing between the two sections of the microstrip differential transmission line (4) is set to 0.0675-0.0825 mm.
10. The inductive coupling structure based on gold wire bonding according to claim 1, characterized in that: The gold wire (5) is arched along the axial direction of the transmission line via (2), the diameter of the gold wire (5) is set to 22.5-27.5um, and the arch height of the gold wire (5) is set to 22.5-27.5um.