CN111555006A - Ka-band grounded coplanar waveguide gold wire transition structure - Google Patents

Abstract

The utility model provides a Ka wave band ground connection coplanar waveguide gold wire transition structure, including ground connection coplanar waveguide, chip and gold wire, ground connection coplanar waveguide includes the base plate, the ground connection bottom, signal line and ground connection top layer, signal line and each ground connection top layer interval set up, the storage tank has openly been seted up to the base plate, the chip is installed in the storage tank, the signal line extends to the one end of storage tank, the gold wire links to each other with the chip, cascade is used for carrying out the impedance transformation stub that impedance matches with the gold wire between the one end of the adjacent chip of signal line and the gold wire, the front of base plate is located to the impedance transformation stub. The Ka-waveband grounding coplanar waveguide gold wire transition structure provided by the application has the advantages that the impedance transformation branch is added in the signal wire and the gold wire, so that impedance matching between the grounding coplanar waveguide and the gold wire can be well realized, the problems of return loss and standing-wave ratio performance deterioration caused by impedance mismatch are effectively solved, the manufacturing process requirements of a planar circuit are met, and the processing and manufacturing are easy.

Description

Ka-band grounded coplanar waveguide gold wire transition structure

technical field

The present application belongs to the technical field of microwave radio, and more particularly, relates to a Ka-band grounded coplanar waveguide gold wire transition structure.

Background technique

Ka-band refers to the radio wave band with frequencies between 26.5 and 40 GHz. Multi-Chip Module (Multi-Chip Module, MCM for short) assembles multiple integrated circuit chips and other chip components on a high-density multi-layer interconnect substrate, and is the mainstream implementation solution for microwave/millimeter wave components. Among them, the connection between the transmission line and the chip is a key link in the assembly process of microwave/millimeter wave components. Common transmission line structures include a microstrip line, a coplanar waveguide (CPW, Coplanar waveguide), a stripline, and the like. Among them, the large-area grounding of the coplanar waveguide is in the same plane as the signal line, which can effectively suppress radiation loss and high-frequency dispersion, and the structure design is flexible. Other components in the chip assembly can be better integrated. For lower frequency multi-chip assemblies, the transmission line and chip can be directly connected by gold wire bonding. However, due to the huge difference in impedance between the grounded coplanar waveguide and the gold wire, directly connecting the gold wire to the signal line in the grounded coplanar waveguide will cause a large electromagnetic wave reflection due to impedance mismatch, which will make the return loss and standing of the entire structure. The wave ratio performance deteriorates, and the higher the frequency, the more severe the deterioration.

SUMMARY OF THE INVENTION

The purpose of the embodiments of the present application is to provide a Ka-band grounded coplanar waveguide gold wire transition structure, so as to solve the problem that the connection between the Ka-band grounded coplanar waveguide and the gold wire existing in the related art will cause return loss and standing due to impedance mismatch. The problem of deteriorating Burpee performance.

In order to achieve the above purpose, the technical solution adopted in the embodiments of the present application is to provide a Ka-band grounded coplanar waveguide gold wire transition structure, including a grounded coplanar waveguide, a chip, and a gold wire connecting the chip and the grounded coplanar waveguide. The grounded coplanar waveguide includes a substrate, a grounding bottom layer arranged on the back of the substrate, a signal line arranged on the front of the substrate, and a grounding surface layer respectively located on both sides of the signal line, each of the grounding surface layers is arranged on On the front surface of the substrate, the signal lines are arranged at intervals from each of the grounding surfaces, an accommodating groove is opened on the front surface of the substrate, the chip is installed in the accommodating groove, and the signal line extends to the accommodating groove At one end of the slot, the gold wire is connected to the chip, an impedance transformation branch used for impedance matching with the gold wire is cascaded between one end of the signal line adjacent to the chip and the gold wire, and the The impedance transformation branch is arranged on the front surface of the substrate, and the impedance transformation branch is located between the two grounding surface layers.

In one embodiment, the impedance transformation branch includes a high-impedance branch and a low-impedance branch, one end of the high-impedance branch is connected to the signal line, and the other end of the high-impedance branch is connected to the low-impedance branch along the The middle part of the signal line in the width direction is connected, and the gold wire is connected to the low-impedance branch.

In one embodiment, the characteristic impedance of the grounded coplanar waveguide is 50Ω, and the impedance transformation branch is a gold layer; the length of the high-impedance branch along the length direction of the signal line is 0.25 mm, and the high-impedance branch is 0.25 mm. The width along the width direction of the signal line is 0.1 mm, the length of the low impedance branch along the length direction of the signal line is 0.25 mm, and the width of the low impedance branch along the width direction of the signal line is 0.75 mm.

In one embodiment, both the signal line and the ground surface layer are gold layers, the width of the signal line is 0.38 mm, and the gap between the signal line and each of the ground surface layers is 0.4 mm.

In one embodiment, the impedance transformation branch is connected to the chip through two gold wires, the two gold wires are arranged in a figure-eight shape along the length direction of the signal line, and the two gold wires are The distance close to one end of the chip is smaller than the distance of the two gold wires close to one end of the impedance transformation branch.

In one embodiment, the span of each of the gold wires is in the range of less than or equal to 300 μm, the range of the arch height of each of the gold wires is in the range of 100 μm to 200 μm, and the distance between the two gold wires is close to one end of the chip. The range is less than or equal to 50 μm, and the range of the distance between the two gold wires close to one end of the impedance transformation branch is 100 μm-250 μm.

In one embodiment, the impedance transformation branch is symmetrically arranged with respect to the center line in the length direction of the signal line, the grounded coplanar waveguide is symmetrically arranged with respect to the center line in the length direction of the signal line, and the two gold wires are arranged about the center line in the length direction of the signal line. The center line in the length direction of the signal line is symmetrically arranged.

In one embodiment, the signal line has two sections, the two sections of the signal line are respectively located at two ends of the accommodating slot, and one end of each of the signal lines adjacent to the chip is respectively connected with the impedance transformation branch The two impedance transformation branches are respectively connected to two ends of the chip through the gold wires.

In one embodiment, at least two rows of ground through holes are respectively provided on both sides of the signal line on the substrate, and each of the ground through holes connects the corresponding ground surface layer and the ground bottom layer; the signal line In the two rows of ground through holes adjacent to the signal line on each side: the distance between two adjacent ground through holes in each row of the ground through holes is in the range of 0.5-1.1 mm, and the ground through holes in the two rows are in the range of 0.5-1.1 mm. The distance between the through holes ranges from 0.5mm to 1.5mm, and the two rows of the ground through holes are arranged in a staggered position along the length direction of the signal line.

In one embodiment, the gap between the impedance transformation branch and each of the ground surface layers is greater than or equal to 0.225mm.

The beneficial effect of the Ka-band grounded coplanar waveguide gold wire transition structure provided by the embodiment of the present application is that compared with the prior art, the present application can well realize grounding coplanarity by adding impedance transformation branches to the signal line and the gold wire. The impedance matching between the waveguide and the gold wire can effectively solve the problems of return loss and VSWR performance deterioration caused by impedance mismatch.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present application more clearly, the following briefly introduces the accompanying drawings that are used in the description of the embodiments or exemplary technologies. Obviously, the drawings in the following description are only for the present application. In some embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without any creative effort.

1 is a schematic three-dimensional structural diagram of a Ka-band grounded coplanar waveguide gold wire transition structure provided by an embodiment of the present application;

FIG. 2 is a top-view structural schematic diagram of the Ka-band grounded coplanar waveguide gold wire transition structure of FIG. 1;

Fig. 3 is the enlarged view of A part in Fig. 1;

Fig. 4 is a partial structural schematic diagram taken along line B-B in Fig. 3;

Fig. 5 is an enlarged view of part of the structure in Fig. 1;

FIG. 6 is an equivalent circuit diagram when the signal line of the grounded coplanar waveguide is directly connected to the chip through a gold wire.

FIG. 7 is an equivalent circuit diagram formed by an impedance transformation branch and a corresponding gold wire in the Ka-band grounded coplanar waveguide gold wire transition structure provided by the embodiment of the present application.

FIG. 8 is an effect diagram of the simulation of the transmission performance of the Ka-band grounded coplanar waveguide gold wire transition structure provided by the embodiment of the present application.

Among them, the main symbols of each accompanying drawing in the figure are:

100-Ka band grounded coplanar waveguide gold wire transition structure;

10-ground coplanar waveguide; 11-substrate; 111-accommodating slot; 112-; 12-ground bottom layer; 13-ground surface layer; 14-signal line;

20-chip;

30 - gold wire;

40-impedance transform branch; 41-high impedance branch; 42-low impedance branch.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer, the present application will be described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application.

It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

In the description of the present application, "plurality" means two or more, unless otherwise expressly and specifically defined. "Several" means one or more than one, unless expressly specifically defined otherwise.

In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "length", "width", "thickness", "inner", "outer", etc. are based on those shown in the accompanying drawings The orientation or positional relationship is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present application.

In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; may be mechanical connection or electrical connection; may be direct connection or indirect connection through an intermediate medium, may be internal communication between two elements or an interaction relationship between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific situations.

Reference in this specification to "one embodiment," "some embodiments," or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the application . Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in other embodiments," etc. in various places in this specification are not necessarily All refer to the same embodiment, but mean "one or more but not all embodiments" unless specifically emphasized otherwise. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

Please refer to FIG. 1. For the convenience of description, three coordinate axes that are perpendicular to each other in space are defined as the X axis, the Y axis and the Z axis, wherein the X axis is the length direction along the signal line, and the Y axis is the width along the signal line. direction, the Z axis is along the thickness direction of the signal line.

Referring to FIG. 1 , FIG. 2 and FIG. 3 , the Ka-band grounded coplanar waveguide gold wire transition structure 100 provided by the present application will now be described. The Ka-band grounded coplanar waveguide gold wire transition structure 100 includes a grounded coplanar waveguide 10 , a chip 20 , a gold wire 30 and an impedance transformation branch 40 . The grounded coplanar waveguide 10 includes a substrate 11 , a grounding bottom layer 12 , a signal line 14 and two grounding surface layers 13 . The surface layers 13 are respectively located on both sides of the signal lines 14 , and the signal lines 14 are spaced apart from the ground surface layers 13 , thereby forming the grounded coplanar waveguide 10 . An accommodating groove 111 is formed on the front of the substrate 11 , the signal line 14 extends to one end of the accommodating groove 111 , that is, the accommodating groove 111 is set at the position corresponding to the signal line 14 , and the chip 20 is installed in the accommodating groove 111 to facilitate the installation of the chip 20, and meets the requirements of the plane circuit manufacturing process, and is easy to process and manufacture. The gold wire 30 is connected to the chip 20 , the impedance transformation branch is arranged on the front surface of the substrate 11 , the impedance transformation branch 40 is used for impedance matching with the gold wire 30 , and the impedance transformation branch 40 connects one end of the signal line 14 adjacent to the chip 20 with the gold wire 30, that is, the signal line 14 is connected to the gold wire 30 by impedance matching through the impedance transformation branch 40, so as to effectively solve the problems of return loss and VSWR performance deterioration caused by impedance mismatch.

Compared with the prior art, in the Ka-band grounded coplanar waveguide gold wire transition structure 100 provided by the present application, by adding impedance transformation branches 40 to the signal line 14 and the gold wire 30, the grounded coplanar waveguide 10 and the gold wire can be well realized. The impedance matching between the wires 30 effectively solves the problems of return loss and VSWR performance deterioration caused by impedance mismatch, and also meets the requirements of the plane circuit manufacturing process and is easy to manufacture.

In one embodiment, please refer to FIG. 3 and FIG. 5 , the impedance transformation branch 40 includes a high-impedance branch 41 and a low-impedance branch 42 , one end of the high-impedance branch 41 is connected to the signal line 14 , and the other end of the high-impedance branch 41 is connected to the low-impedance branch 41 . The impedance branch 42 is connected along the middle of the width direction of the signal line 14, and the gold wire 30 is connected with the low impedance branch 42, so as to realize the connection between the signal line 14 and the gold wire 30, and the impedance transformation branch 40 can form a T-shaped structure. In order to better realize the impedance matching between the gold wire 30 and the signal line 14 .

Please refer to FIG. 6 . The circuit shown in FIG. 6 is an equivalent circuit of the gold wire 30 when the chip 20 and the signal line 14 are directly connected by the gold wire 30 . The equivalent circuit includes two inductors L1, two resistors R1, two capacitors C1 and one capacitor C2, wherein the inductor L1, resistor R1, resistor R1 and inductor L1 are connected in series in sequence, and one inductor L1 is far from one end of the two resistors R1 For connecting the chip end of the chip 20, the end of the other inductor L1 away from the two resistors R1 is the signal line end for connecting the signal line 14, that is, from the chip end to the signal line end, the inductor L1, the resistor R1, the resistor R1 and the inductor L1 in series; and the chip end is grounded through a capacitor C1, the signal line end is grounded through another capacitor C1, and the two resistors R1 are grounded through a capacitor C2.

Please refer to FIG. 7 , the above-mentioned T-shaped impedance transformation branch 40 is used to connect the gold wire 30 and the signal line 14 , and an equivalent circuit of the impedance transformation branch 40 and the gold wire 30 is used, and the equivalent circuit includes two inductors L1 and two resistors R1 , one inductor Lp, one capacitor Cp, two capacitors C1 and one capacitor C2, wherein the inductor L1, resistor R1, resistor R1, inductor L1 and inductor Lp are connected in series in sequence, and one end of the inductor L1 away from the inductor Lp is used to connect the chip At the chip end of 20, the end of the inductor Lp away from the two resistors R1 is the signal line end for connecting the signal line 14, that is, from the chip end to the signal line end, the inductor L1, the resistor R1, the resistor R1, the inductor L1 and the inductor Lp are in sequence. The chip end is grounded through a capacitor C1, the two resistors R1 are grounded through a capacitor C2, the other capacitor C1 is connected in parallel with the capacitor Cp, and the end of the inductor Lp away from the signal line is grounded through the capacitor Cp. Then the inductor Lp and the capacitor Cp can form an L-type impedance matching network, that is, the equivalent circuit using the impedance transformation branch 40 is equivalent to adding L-type impedance matching to the signal line end of the equivalent circuit using the gold wire 30 to connect the signal line 14 directly. network, so that the ultra-wideband impedance matching between the grounded coplanar waveguide 10 and the gold wire 30 can be better achieved. Of course, in some embodiments, other shapes of impedance transformation branches 40 may also be used to achieve impedance matching between the gold wire 30 and the signal line 14 .

In one embodiment, referring to FIGS. 3 to 5 , the characteristic impedance of the grounded coplanar waveguide 10 is 50Ω, and the impedance transformation branch 40 is a gold layer; the length of the high impedance branch 41 along the length direction of the signal line 14 is 0.25 mm, and the height The width of the impedance branch 41 along the width direction of the signal line 14 is 0.1 mm, the length of the low impedance branch 42 along the length direction of the signal line 14 is 0.25 mm, and the width of the low impedance branch 42 along the width direction of the signal line 14 is 0.75 mm. The impedance transformation branch 40 can well achieve impedance matching between the gold wire 30 and the grounded coplanar waveguide 10 with a characteristic impedance of 50Ω in the Ka-band, ensuring good link transmission performance.

In one embodiment, please refer to FIG. 1 to FIG. 3 , the signal line 14 and the ground surface layer 13 are both gold layers, the width of the signal line 14 is 0.38mm, and the gap between the signal line 14 and each ground surface layer 13 is 0.4mm , so that the grounded coplanar waveguide 10 has good transmission performance, and the grounded coplanar waveguide 10 has a characteristic impedance of 50Ω, which improves the applicable range of the grounded coplanar waveguide 10 .

In one embodiment, please refer to FIG. 3 and FIG. 4 , the thickness of the gold layer is in the range of 10-20 μm, that is, the impedance transformation branch 40 is made of gold material, the thickness of the impedance transformation branch 40 is in the range of 10-20 μm, and the signal line 14 The ground surface layer 13 is made of gold material, and the thickness of the signal line 14 and the ground surface layer 13 is in the range of 10-20 μm, so as to ensure that the grounded coplanar waveguide 10 has good transmission performance, and the impedance transformation branch 40 can well realize the gold wire 30 It is matched with the impedance between the signal lines 14 . In some embodiments, the thickness of each gold layer is 15 μm to ensure good transmission performance and impedance matching characteristics of the grounded coplanar waveguide 10 and the impedance transformation branch 40 .

In one embodiment, the thicknesses of the impedance transformation branch 40 , the signal line 14 and the ground surface layer 13 are equal, so as to facilitate processing and fabrication, for example, they can be fabricated on the substrate 11 by printing.

In one embodiment, please refer to FIG. 3 and FIG. 5 , the impedance transformation branch is connected to the chip 20 through two gold wires 30 , and the two gold wires 30 are arranged in a figure-eight shape along the length direction of the signal line 14 . The distance between one end of the 30 near the chip 20 is smaller than the distance between the two gold wires 30 near one end of the impedance transforming branch. Two gold wires 30 are used to connect the impedance transformation branch and the chip 20, so that the two gold wires 30 can better form a symmetrical structure, reduce impedance and improve transmission performance.

In one embodiment, please refer to FIG. 3 to FIG. 5 , the span of each gold wire 30 is in the range of less than or equal to 300 μm, the arch height of each gold wire 30 is in the range of 100 μm-200 μm, and the two gold wires 30 are close to the chip The range of the distance between one end of the 20 is less than or equal to 50 μm, and the distance between the two gold wires 30 close to one end of the impedance transformation branch is in the range of 100 μm-250 μm, so that the gold wire 30 has smaller resistance and inductance characteristics, that is, the gold wire 30 has smaller resistance and inductance characteristics. The impedance of the wire 30 improves the transmission performance of the gold wire 30, and is well matched with the impedance transformation branch 40, and is also convenient for processing.

In some embodiments, the span of each gold wire 30 is 260 μm, the arch height of each gold wire 30 is 150 μm, the distance between the two gold wires 30 close to one end of the chip 20 is 25 μm, and the two gold wires 30 are close to the impedance transformation branch The distance between one end is 175μm, so that the gold wire 30 has smaller resistance and inductance characteristics, that is, the impedance of the gold wire 30 is reduced, the transmission performance of the gold wire 30 is improved, and the connection impedance transformation branch of the wire 30 is better guaranteed. 40 is matched with the chip 20 and the stub 40 for better impedance transformation of the gold wire 30.

In one embodiment, please refer to FIG. 1 , FIG. 3 and FIG. 5 , the impedance transformation branches are arranged symmetrically with respect to the center line in the length direction of the signal line 14 , and the grounded coplanar waveguide 10 is symmetrically arranged with respect to the center line in the length direction of the signal line 14 . The gold wire 30 is symmetrically arranged with respect to the center line in the length direction of the signal line 14, so that the grounded coplanar waveguide 10, the gold wire 30 and the impedance transformation branch form a symmetrical structure, which is convenient for processing and manufacture, and ensures the transition of the gold wire of the Ka-band grounded coplanar waveguide The structure 100 has good transmission performance and low return loss. Of course, in some embodiments, if the substrate 11 or the chip 20 itself has an asymmetric structure, it is only necessary to adjust the positions of the signal wire 14 , the impedance transformation branch and the gold wire 30 accordingly, and the gold wire 30 and the signal wire 14 can also be realized. Good impedance matching between them ensures good transmission.

In one embodiment, please refer to FIG. 1 , FIG. 3 and FIG. 5 , the signal line 14 is divided into two sections, the two sections of the signal line 14 are respectively located at two ends of the accommodating groove 111 , and each signal line 14 is connected to one end adjacent to the chip 20 respectively. There are impedance transformation branches, and the two impedance transformation branches are respectively connected to both ends of the chip 20 through gold wires 30 , which not only facilitates the installation of the chip 20 , but also realizes the matching connection between the two ends of the chip 20 and the two signal lines 14 . In other embodiments, when only one end of the chip 20 needs to be connected to the signal line 14 , the accommodating groove 111 can be provided at one end of the substrate 11 , so that the chip 20 is mounted on the edge of the substrate 11 .

In one embodiment, please refer to FIG. 1 and FIG. 2 , when the signal line 14 has two sections, the lengths of the two sections of the signal line 14 are equal, and the accommodating slot 111 is located in the middle of the substrate 11 , so that the grounded coplanar waveguide is 10 is symmetrically arranged with respect to the center line in the longitudinal direction of the substrate 11 to facilitate design and manufacture, and to ensure good transmission performance of the grounded coplanar waveguide 10 .

In one embodiment, please refer to FIG. 1 and FIG. 2 , at least two rows of ground vias are respectively provided on both sides of the signal line 14 on the substrate 11 , and each ground via is connected to the corresponding ground surface layer 13 and the ground bottom layer 12 to enhance the The transmission of the grounded coplanar waveguide 10 improves transmission efficiency and reduces loss.

In one embodiment, please refer to FIG. 1 and FIG. 2 , in the two rows of ground vias adjacent to the signal line 14 on each side of the signal line 14 : the distance range between two adjacent ground vias in each row of ground vias is 0.5-1.1mm; the distance between the two rows of ground through holes is 0.5mm-1.5mm, and the two adjacent rows of ground through holes are arranged at a dislocation along the length of the signal line 14 to better enhance the grounded coplanar waveguide 10 transmission efficiency, reduce loss.

In one embodiment, the diameter of each ground through hole is in the range of 0.1-0.3 mm, so as to facilitate processing and fabrication. In one embodiment, the diameter of each grounding via is 0.2 mm, which is convenient for fabrication, and can improve the transmission efficiency of the grounded coplanar waveguide 10 , so that the transmission efficiency of the grounded coplanar waveguide 10 can be improved and the manufacturing process is simple to achieve. balance.

In one embodiment, in the two rows of ground through holes adjacent to the signal line 14 on each side of the signal line 14: the connection between the axes of any three adjacent ground through holes is an isosceles triangle, so as to better prevent electromagnetic leakage, so as to improve the transmission efficiency of the grounded coplanar waveguide 10 .

In one embodiment, in the two rows of ground through holes adjacent to the signal line 14 on each side of the signal line 14: the connection between the axes of any three adjacent ground through holes is an equilateral triangle, which is convenient for design and manufacture, and also The transmission efficiency of the grounded coplanar waveguide 10 can be improved.

In one embodiment, each side of the signal line 14 is adjacent to the two rows of ground through holes of the signal line 14 : the distance between two adjacent ground through holes in each row of ground through holes is 1 mm to facilitate fabrication.

In one embodiment, please refer to FIG. 3 , the gap between the impedance transformation branch and each ground surface layer 13 is greater than or equal to 0.225mm, which meets the requirements of most planar circuit processing technologies, facilitates fabrication and reduces costs.

In one embodiment, please refer to FIG. 1 and FIG. 4 , the dielectric constant of the substrate 11 ranges from 5.0 to 10.0, and the dielectric loss factor tanα of the substrate 11 is less than or equal to 0.004 to ensure good transmission performance of the grounded coplanar waveguide 10 . In some embodiments, the substrate 11 can be made of a ceramic material, so that the grounded coplanar waveguide 10 can be fabricated by a low temperature co-fired ceramic process. Of course, in some embodiments, the substrate 11 can also be made of other materials.

In one embodiment, the substrate 11 is rectangular, the signal lines 14 are arranged along the length direction of the substrate 11 , the length direction of the substrate 11 is the length direction of the signal lines 14 , that is, the X-axis direction; the width direction of the substrate 11 is the signal line The width direction of the substrate 14 is the Y-axis direction; the thickness direction of the substrate 11 is the thickness direction of the signal line 14 , that is, the Z-axis direction. With this structure, the grounded coplanar waveguide 10 can be better made into a symmetrical structure, so as to improve the transmission performance and reduce the transmission loss.

In one embodiment, the length of the substrate 11 is 25.4 mm, the width of the substrate 11 is 12.7 mm, and the thickness of the substrate 11 is 0.31 mm, so that the Ka-band grounded coplanar waveguide gold wire transition structure 100 is small in size and convenient use.

In one embodiment, the distance between the inner wall of the accommodating groove 111 and the side surface of the chip 20 is in the range of 60-100 μm, so as to facilitate the installation of the chip 20 in the accommodating groove 111 . In one embodiment, the distance between the inner wall of the accommodating groove 111 and the side surface of the chip 20 is 80 μm, which is convenient not only for installing the chip 20 in the accommodating groove 111 but also for fixing the chip 20 .

In one embodiment, the front surface of the chip 20 is flush with the front surface of the grounded coplanar waveguide 10, which can better meet the requirements of the planar circuit processing technology and improve the manufacturing accuracy.

In some embodiments, the bottom surface of the chip 20 can be grounded to the ground plane 12 through a metal pad to reduce transmission loss.

Please refer to FIG. 8 , which is an effect diagram of the transmission performance simulation of the Ka-band grounded coplanar waveguide gold wire transition structure 100 provided by the embodiment of the present application, wherein a 50Ω characteristic impedance metal-backed coplanar waveguide is used instead of the chip 20 for electromagnetic simulation. The abscissa axis Freq in the figure is the frequency, the unit is GHz; the left ordinate axis Insertion/Return Loss is the insertion/return loss, the unit is dB; VSWR (Voltage Standing Wave Ratio, standing wave ratio, the full name is Voltage Standing Wave). ratio, abbreviated as VSWR), and the ordinate axis VSWR on the right is the standing wave ratio. Curve Info curve information, Y Axis Y axis (ie the ordinate axis). Among them, the line S(1,1) is the curve corresponding to the return loss of each frequency, the frequency at the high point m2 on the line S(1,1) is 32.98GHz, and the return loss is -23.0291dB; the line S(2, 1) is the curve corresponding to the insertion loss of each frequency, the frequency at the low point m1 on the line S(2,1) is 40GHz, and the insertion loss is -1.0347dB; the line V(1) is the curve corresponding to the standing wave ratio of each frequency, The frequency at the high point m3 on line V(1) is -23.0291 GHz and the VSWR is 1.1518. As can be seen from the figure, the Ka-band grounded coplanar waveguide gold wire transition structure 100 of the embodiment of the present application has excellent transmission performance in the Ka-band, with insertion loss less than 1.1dB, return loss greater than 23.0dB, and standing wave ratio less than 1.2.

The Ka-band grounded coplanar waveguide gold wire transition structure 100 in the embodiment of the present application can be fabricated by using the LTCC (LowTemperature Co-fired Ceramic, LTCC for short) process, or other planar printing processes, for example, it can be fabricated on green ceramic The cavity is pulled out from the corresponding position of the chip, stacked from bottom to top, and each layer of metal patterns and holes are printed; then sintered and formed, of course, the substrate 11 can also be electroplated and cleaned, and then the chip 20 can be installed in sequence by the patch process. , Gold wire 30 bonding.

The Ka-band grounded coplanar waveguide gold wire transition structure 100 in the embodiment of the present application can be applied to Ka-band transceiver components, and can also be applied to devices such as microwave communication, radar systems, and electronic countermeasures.

The above descriptions are only optional embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection of the present application. within the range.

Claims (10)

1. The Ka-band grounding coplanar waveguide gold wire transition structure comprises a grounding coplanar waveguide, a chip and a gold wire, wherein the gold wire is connected with the chip and the grounding coplanar waveguide, the grounding coplanar waveguide comprises a substrate, a grounding bottom layer arranged on the back surface of the substrate, a signal wire arranged on the front surface of the substrate and grounding surface layers respectively arranged on two sides of the signal wire, the grounding surface layers are arranged on the front surface of the substrate, the signal wire and the grounding surface layers are arranged at intervals, a containing groove is formed in the front surface of the substrate, the chip is arranged in the containing groove, the signal wire extends to one end of the containing groove, and the gold wire is connected with the chip, and the Ka-band grounding coplanar waveguide gold wire transition structure is characterized: and an impedance transformation branch which is used for carrying out impedance matching with the gold wire is cascaded between one end of the signal wire, which is adjacent to the chip, and the gold wire, the impedance transformation branch is arranged on the front surface of the substrate, and the impedance transformation branch is positioned between the two grounding surface layers.
2. 2. The Ka band ground coplanar waveguide gold wire transition structure of claim 1, wherein: the impedance transformation branch comprises a high-impedance branch and a low-impedance branch, one end of the high-impedance branch is connected with the signal wire, the other end of the high-impedance branch is connected with the middle of the low-impedance branch along the width direction of the signal wire, and the gold wire is connected with the low-impedance branch.
3. 3. The Ka band ground coplanar waveguide gold wire transition structure of claim 2, wherein: the characteristic impedance of the grounding coplanar waveguide is 50 omega, and the impedance transformation branch is a gold layer; the high impedance stub is followed the length of signal line length direction is 0.25mm, the high impedance stub is followed the width of signal line width direction is 0.1mm, the low impedance stub is followed the length of signal line length direction is 0.25mm, the low impedance stub is followed the width of signal line width direction is 0.75 mm.
4. 4. The Ka-band grounded coplanar waveguide gold wire transition structure of claim 3, wherein: the signal lines and the grounding surface layers are all made of gold layers, the width of each signal line is 0.38mm, and gaps between the signal lines and the grounding surface layers are 0.4 mm.
5. 5. The Ka-band grounded coplanar waveguide gold wire transition structure of any one of claims 1 to 4, wherein: the impedance transformation branch is connected with the chip through the two gold wires, the two gold wires are arranged in a splayed shape along the length direction of the signal wire, and the distance between the two gold wires and the end, close to the chip, of the two gold wires is smaller than the distance between the two gold wires and the end, close to the impedance transformation branch, of the two gold wires.
6. 6. The Ka-band grounded coplanar waveguide gold wire transition structure of claim 5, wherein: the span range of each gold wire is less than or equal to 300 mu m, the arch height range of each gold wire is 100 mu m-200 mu m, the distance range of one end, close to the chip, of each gold wire is less than or equal to 50 mu m, and the distance range of one end, close to the impedance transformation branch, of each gold wire is 100 mu m-250 mu m.
7. 7. The Ka-band grounded coplanar waveguide gold wire transition structure of claim 5, wherein: the impedance transformation branch sections are symmetrically arranged relative to the central line of the length direction of the signal wire, the grounding coplanar waveguide is symmetrically arranged relative to the central line of the length direction of the signal wire, and the two gold wires are symmetrically arranged relative to the central line of the length direction of the signal wire.
8. 8. The Ka-band grounded coplanar waveguide gold wire transition structure of any one of claims 1 to 4, wherein: the signal lines are two sections, the two sections of signal lines are respectively located at two ends of the accommodating groove, one end, adjacent to the chip, of each signal line is respectively connected with the impedance transformation branch sections, and the two impedance transformation branch sections are respectively connected with two ends of the chip through the gold wires.
9. 9. The Ka-band grounded coplanar waveguide gold wire transition structure of any one of claims 1 to 4, wherein: at least two rows of grounding through holes are respectively arranged on the two sides of the signal line on the substrate, and each grounding through hole is connected with the corresponding grounding surface layer and the corresponding grounding bottom layer; in two rows of the ground vias, each side of the signal line is adjacent to the signal line: the distance range between two adjacent ground through holes in each row of ground through holes is 0.5-1.1mm, the distance range between the two rows of ground through holes is 0.5-1.5 mm, and the two rows of ground through holes are arranged along the length direction of the signal wire in a staggered mode.
10. 10. The Ka-band grounded coplanar waveguide gold transition structure of any one of claims 1 to 4, wherein the gap between the impedance transformation stub and each of the grounding surfaces is greater than or equal to 0.225 mm.

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