HIGH-FREQUENCY SUPPLY CABLE AND ELECTRONIC COMPONENT WITH HIGH-FREQUENCY SUPPLY CABLE

Description

Field of the invention

[0001] The invention relates generally to high-frequency leads. More particularly, the invention relates to high-frequency leads with changes in the direction of their path. Furthermore, the invention relates to electronic components having such high-frequency leads. Background of the invention

[0002] High-frequency supply lines are generally known. Such supply lines are particularly required to supply electronic components with data. This is described, for example, in the applicant's application DE 10 2020 105 772.5.

[0003] In such cases, high-frequency leads arranged on a submount are used, which include a signal conductor and a ground conductor.

[0004] Such conductor tracks and their properties are described, for example, in Agilent Technologies, Advanced Design System 1.5, Circuit Components, Distributed Components, Chapter 2 (available at http: / / literature.cdn.keysight.com / litweb / pdf / ads15 / ccdist / ccdist026.html).

[0005] WO 2007 / 000934 A1 and DE 10 2005 038456 A1 disclose conductor track arrangements for high-frequency signals, comprising a layered, flat signal conductor arranged on the carrier, wherein the outer edge and the inner edge in the deflection region of the signal conductor are curved at least in sections. WO 2014 / 089823 A1 discloses another variant of the design of the deflection region.

[0006] Depending on the arrangement and wiring of the components to be supplied, a change in the direction of the lines may be necessary for geometric reasons. The problem here is that the deflection can lead to capacitance changes along the line. These capacitance changes can lead to undesirable increased return loss. An abrupt 90° change even results in significant reflection. If the direction is to change by 90°, the state of the art provides for the outer side of the conductor to be at a deflection angle of 45° to both the previous and the new propagation directions, creating a deflection section, or chamfer, that is inclined to both propagation directions. Another option is to provide a rounded line section. However, this option has the disadvantage of requiring more space.

[0007] A disadvantage of a 45° bevel design is that the deflection section acts as an antenna, resulting in reflection losses in the deflection area of ​​the conductor. This type of deflection design also limits the bandwidth of the high-frequency signals that can be transmitted along the conductor.

[0008] In addition to reflection losses, higher-order waves can also occur at very high frequencies, or can propagate above a certain cutoff frequency, so that not only the fundamental wave but also higher-order waves propagate on the line. The fundamental wave and all higher-order waves are referred to as the line's eigenwaves. On an undisturbed line, the eigenwaves are independent and do not interfere with each other. However, in the event of a disturbance, the eigenwaves are coupled, so that the properties of the fundamental wave also change as soon as a higher-order wave propagates. If a line is no longer uniform or inhomogeneous in the direction of propagation, higher-order waves are excited. A change in direction represents such an inhomogeneity. A line angle is therefore also referred to as a discontinuity.With the aforementioned 45° chamfer, capacitance compensation is achieved through the bevel, i.e., through an abrupt change in the conductor cross-section. Therefore, higher-order waves are excited at correspondingly high frequencies at this conduction angle.

[0009] Therefore, the object of the invention is to provide a high-frequency feed line which, compared to the prior art, has lower reflection losses in deflection regions and preferably also a higher cut-off frequency for higher-order waves and allows the use of a higher bandwidth compared to the prior art.

[0010] This object is achieved by the subject matter of the independent claims. Further embodiments and advantageous developments of the invention are the subject matter of the dependent claims.

[0011] Accordingly, a conductor track arrangement for high-frequency signals is provided, comprising a carrier and a layered signal conductor arranged on the carrier, delimited by at least one inner edge and at least one outer edge, which extends from one end to another of the signal conductor, wherein the signal conductor of the conductor track arrangement changes its direction in a deflection region between the ends and has a minimum width, wherein the minimum width in the deflection region of the signal conductor is smaller than the widths at the ends of the signal conductor, wherein the outer edge and the inner edge are curved at least in sections in the deflection region, and wherein the curvature of the inner edge and the curvature of the outer edge each have a center, wherein the center of the curvature of the inner edge and the center of the curvature of the outer edge are arranged offset from one another,so that the curvature of the inner edge and the curvature of the outer edge are eccentric to each other, in particular the centers differ from each other. Due to the curvature, less metal can be used for the signal conductor in the deflection area, which can compensate for the typically increased capacitance in the deflection area. Advantageously, the outer edge and the inner edge in the deflection area are curved at least in sections.

[0012] This allows the increased capacity in the deflection area to be compensated more effectively.

[0013] In an example which is not part of the invention, it is provided that the minimum width is reduced by a factor in the range of 0.5 to 0.95, preferably in the range of 0.6 to 0.8, compared to the width at one of the ends of the signal conductor.

[0014] To make the capacity compensation individually adaptable, at least one of the following features is provided: the radius of the curvature of the outer edge is greater than the radius of the curvature of the inner edge, the curvature of the outer edge and / or the inner edge is continuous, in particular uninterrupted, the curvature of the outer edge and / or the inner edge is continuous, the curvature of the outer edge and / or the inner edge is discontinuous the width of the signal conductor changes continuously in the deflection region, wherein the course of the width is preferably continuously differentiable at least twice, the minimum width of the signal conductor lies within the middle third of the deflection region, preferably in the middle of the deflection region. The width of the signal conductor in the deflection region, or between at least one curved edge and the other edge, preferably between two curved edges, is defined within the meaning of the invention by the distance between a tangent of the inner curvature of the inner edge and the tangent of the inner curvature of the outer edge, in particular defined by a common perpendicular to the tangent of the inner curvature of the outer edge and the tangent of the inner curvature of the inner edge. Preferably, one perpendicular in this case is perpendicular, i.e., at a 90° angle to the two tangents of the inner curvatures, with the length of the perpendicular corresponding to the width of the signal conductor, or the distance between the inner edges and the outer edge.

[0015] The curvature of the inner edge and the curvature of the outer edge are eccentric to one another, in particular not concentric, and preferably such that the width of the signal conductor in the deflection region is smaller than at one end, preferably both ends of the signal conductor. This leads to an increase in the cutoff frequency of the higher-order waves, so that the higher-order waves only arise at a higher frequency and the fundamental wave is no longer disturbed, or only slightly disturbed. If the width of the signal conductor changes continuously and / or the outer edge and the inner edge are continuous, a capacitance jump can be avoided, and therefore capacitance compensation can also take place without an abrupt jump in the conductor cross-section.

[0016] Advantageously, the shape of the signal conductor can also be adapted to the geometric configuration of the submount without having to forego the aforementioned advantages. For this purpose, the signal conductor in the deflection region, or the deflection region, is shaped asymmetrically, or symmetrically, in particular such that the deflection region has a mirror axis along the angle bisector of the deflection angle. The deflection region can also extend from one end to the other end of the signal conductor. In this way, the signal conductor can, for example, be curved over its entire length so that the signal line is not disrupted by a kink.

[0017] According to a further example, which is not part of the invention, a conductor track arrangement for high-frequency signals is provided, comprising a carrier and a layered signal conductor arranged on the carrier and delimited by two edges, as well as a ground conductor arranged on the carrier. The signal conductor of the conductor track arrangement changes its direction in a deflection region between two limbs, wherein in the deflection region at least one of the edges of the signal conductor has at least two deflection sections that are at an angle to one another. Accordingly, an at least two-stage deflection of the edge in the new direction is provided.

[0018] Surprisingly, this approach not only reduces return loss, but also allows for fine adjustment of the deflection sections, allowing the impedance to be adapted to the intended signal frequency.

[0019] In order to combine the aforementioned advantages of reducing the return loss and the reduced capacitance, it can also be provided that one edge, for example the inner or outer edge, is curved at least in sections and the other edge, preferably the outer edge or inner edge, has at least two or more deflection sections.

[0020] In a particularly preferred embodiment, the signal conductor is deflected by 90°, or by an angle close to 90°. Specifically, it is provided that the deflection in the deflection region occurs at an angle in the range of 75° to 105°, preferably, as mentioned, 90°. Advantageously, the conductor track arrangement is designed as a microstrip line, a coplanar waveguide, or a CBCPW arrangement. A conductor track arrangement designed as a microstrip line is preferred. This enables a particularly compact design and, in particular, simple production with comparatively few manufacturing steps. For this purpose, the conductor track arrangement preferably comprises a ground conductor, in particular a layered one, which is arranged opposite the layered signal conductor, wherein at least one of the following features applies to the distance between the ground conductor and the signal conductor: the distance is in the range between 0.025 mm and 0.5 mm, preferably in the range between 0.05 mm and 0.4 mm, the width at one end of the signal conductor is greater than the distance between the ground conductor and the signal conductor by a factor in the range between 0.5 and 7.5, preferably in a range between 0.6 and 5, The ratio of the distance between the signal conductor and the ground conductor to the difference between the width of the signal conductor at one of its ends (35, 36) and the minimum width of the signal conductor has a value in the range between 0.5 and 2.

[0021] These ranges are particularly favorable for intended impedances between 15 ohms and 65 ohms, in particular between 20 ohms and 60 ohms, or even at exactly 20 ohms or 60 ohms. Such value ranges are preferred when the signal conductor is arranged on a submount made of glass or ceramic, in particular Al 2 O 3 , wherein the submount can have a thickness between 0.025 mm and 0.5 mm.

[0022] Since the width of the signal conductor and the distance between the signal conductor and the ground conductor have a significant influence on the capacitance, the capacitance can be optimally adjusted to a desired application using the aforementioned values ​​of these parameters, but in particular to achieve particularly good signal transmission at very high frequencies, for example above 80 GHz. The conductor track arrangement is therefore designed such that a cutoff frequency, in particular for the generation of higher-order waves, is above 60 GHz, preferably above 70 GHz. This particularly applies to the design of the line curvature of the signal conductor and / or a reduced width W min in the deflection region, in particular in conjunction with curved edges 2, 3. The invention is explained in more detail below with reference to the attached figures. Short description of the characters:

[0023] Fig. 1shows the geometry of a conductor track arrangement with a 45° deflection according to the state of the art. In the Fig. 2 to 4 different configurations of conductor track arrangements are shown. Fig. 5 shows a diagram with the return loss summed over a wide frequency range as a function of the deflection angle. Fig. 6 shows an electronic component. Fig. 7 shows a conductor arrangement with two curved edges in which the signal conductor has a constant width. Fig. 8 shows in two partial images conductor track arrangements with two curved edges, in which the signal conductor is narrower in the deflection area than at the ends of the signal conductor. Fig. 9 shows a construction for determining a desired width of the signal conductor in the deflection area. Fig. 10 shows the insertion loss as a function of signal frequency for a signal conductor with a 45° bevel when used in a transistor outline package (TO package). Fig. 11 shows the return loss as a function of signal frequency for a signal conductor with a 45° bevel when used in a TO package. Fig. 12 shows the insertion loss as a function of signal frequency for a signal conductor with constant line width and curved edges when used in a TO package. Fig. 13 shows the return loss as a function of signal frequency for a signal conductor with constant line width and curved edges when used in a TO package. Fig. 14 shows the insertion loss as a function of signal frequency for a signal conductor with variable line width and curved edges when used in a TO package. Fig. 15 shows the return loss as a function of signal frequency for a signal conductor with variable line width and curved edges when used in a TO package. Fig. 16shows the insertion loss and the signal frequency as a function of different signal conductor geometries on a thick submount. Fig. 17 shows the return loss as a function of signal frequency for different signal conductor geometries on a thick submount. Fig. 18 shows the insertion loss as a function of signal frequency for different signal conductor geometries on a thin submount. Fig. 19 shows the return loss as a function of signal frequency for different signal conductor geometries on a thin submount. Fig. 20 shows a schematic diagram of a signal conductor for use in a TO package. Fig. 21 shows in three partial images a submount in cross-section with different electric fields. Detailed description of the invention

[0024] Fig. 1shows the signal conductor 10 of a conductor track arrangement 1 with a deflection of 90° with respect to the previous and the new propagation direction in a deflection region 4, or a deflection region with a beveled outer edge. The conductor-track-shaped or layer-shaped signal conductor 10 has an outer edge 2 and an inner edge 3. In the deflection region 4, the outer edge 2 bends at a deflection angle of 45° relative to the previous propagation direction, so that the contour of the conductor has a bevel 8.

[0025] If the signal conductor 10, as in Fig. 1 shown, has a width W, a square connection has a width D of the signal conductor along the mirror axis, which is created by the bevel by a value X and due to the described design of the deflection, a miter X. According to the mentioned source from Agilent Technologies, the optimal miter applies: X D = 0 , 52 + 0 , 65 × e − 1 , 35 × W H

[0026] H denotes the thickness of the conductor track. For D, obviously, D = 2 × W .

[0027] For typical dimensions of W = 500 µm and H = 150 µm, the miter X is: X = 372 , 8 μm

[0028] This will continue to be used as a reference model.

[0029] In the Fig. 2 to 4 Preferred configurations of conductor track arrangements 1 are shown. An example of a particularly preferred configuration is shown Fig. 2 The signal conductor 10 and the ground conductor 11 are arranged on opposite sides of the carrier 16. Such a configuration is known to those skilled in the art as a so-called microstrip line. Generally, the carrier 16 can be a submount 17. Such a submount can be arranged on a base of a housing for an electronic component. In particular, a base for a TO (transistor outline) housing is intended here.

[0030] Submount 17 can be made of aluminum nitride ceramic, for example, or more generally, a ceramic containing aluminum nitride. Other materials with good thermal conductivity can also be used, such as glass, or glass and ceramic. A glass submount can also be used for the high-frequency supply line. Due to its low thickness, thin glass can be particularly suitable. For submount thicknesses of less than 0.2 mm, for example, the significantly poorer thermal conductivity can be partially compensated. The decisive factor is the so-called thermal resistance. The thinner a substrate, the lower its thermal resistance.

[0031] The configuration of the Fig. 3is based on the fact that the signal conductor 10 and the ground conductor 11 are arranged on the same side of the carrier 16. The signal conductor 10 runs in a gap 18 in the ground conductor 11. The example thus represents a coplanar conductor path arrangement (CPW = coplanar waveguide).

[0032] A variant of a coplanar conductor track arrangement 1 shows Fig. 4 . In addition to the conductor tracks of the ground conductor 11 arranged coplanar with the signal conductor 10, there is also a conductor track of the ground conductor 11 arranged on the opposite side of the carrier 16. Such an arrangement is referred to as CBCPW (" c inductor b acked c O p lanar w aveguide"). All embodiments have in common that the deflection takes place in at least two stages.

[0033] The following model parameters were used for the conductor track arrangements: The substrate on which the microstrip-shaped conductor track arrangement is applied is made of aluminum nitride ceramic with a permittivity of 8.8. The dielectric loss factor tan(δ) is 0.001. The conductor tracks, particularly the signal conductor 10, are made of gold. The conductivity of the gold conductor track is 41,000,000 Siemens / m.

[0034] As can be seen from the curves, the simple 45° bevel exhibits the highest losses. At high signal frequencies between 30 GHz and 45 GHz, the arrangement with a 30° deflection angle exhibits particularly low attenuation. To evaluate the angle dependence of the return loss across the entire high-frequency range, the attenuations mag(S11(f)) were summed for frequencies fn in the range from 1 GHz to 50 GHz: S = ∑ f n = 1 GHz 50 GHz mag S 11 f n

[0035] The result of this summation is in Fig. 5 shown. Fig. 5 shows a diagram with the amplitudes, or absolute values ​​mag(S 11 ), of the return loss S 11 summed in steps of 220 MHz in the frequency range from 1 GHz to 50 GHz for the various deflection angles from 28° to 32°. The course of the curve shown shows a clear minimum for a deflection angle of 30°. The summed return loss at the deflection section according to equation (3) is less than 1000 for deflection angles in the range from 28° to 30°. Such values ​​can also be achieved with other geometries of deflection regions with multiple deflection sections along an edge. Therefore, in general, one embodiment provides that the deflection region 4 is shaped such that the sum S of the values ​​of the scattering parameter S11 for frequencies spaced 1 GHz according to equation (3) in a frequency range from 1 GHz to 50 GHz is less than 1000.

[0036] This choice of deflection angle and unequal length of the deflection sections achieves the following advantages: Compared to a simple 45° deflection according to the prior art, better control of the capacitance of the corner of the conductor track in the deflection area is achieved. This increases the bandwidth of the signal used for data transmission. Due to the minimum deflection angle of 30°, one embodiment generally provides for the deflection angle of an edge 2, 3, preferably the outer edge 3, at the transition from a leg 13, 14 of the signal conductor 10 to the adjacent deflection section 5 to be between 29° and 31°.

[0037] This disclosure also generally relates to electronic components which are installed in a housing and are connected to the conductor track arrangement described here for the transmission of high-frequency electrical signals. One component of the housing is typically a base on which the electronic component is fastened and via which the signal is supplied. In general, a base 20 for an electronic component with an electronic component 28 and a conductor track arrangement 1 according to this disclosure is provided for this purpose, wherein the base has an electrical feedthrough 22, and wherein the electronic component 28 and the electrical feedthrough 22 are both connected to the signal conductor 10 of the conductor track arrangement 1, such that electrical signals are conducted from the feedthrough 22 via the signal conductor 10 to the component 28.In particular, the feedthrough 22 and the electronic component are connected to one of the legs 13, 14, so that the electrical signals flow successively through one leg, the deflection area 4 and then the other leg.

[0038] Furthermore, this disclosure also relates to an electronic component with a socket. The electronic component 30 is a component with a housing in which the electronic component 28 and the conductor track arrangement 1 are enclosed. In particular, the housing can comprise a socket 20 and a cap 31.

[0039] An electronic component 30 with such a socket 20 is shown schematically Fig. 6An optoelectronic converter is preferably used as the electronic component 28 in the electronic component 30. Thus, the electronic component 28 can be a laser diode to convert high-frequency electrical signals for optical signal transmission. Conversely, the electronic component 28 can also be a photodiode to convert optically transmitted data back into electrical signals.

[0040] The housing of the electronic component 30 can, for example, be a TO housing (TO = "Transistor Outline"). For an optoelectronic converter as the electronic component 28, the cap 31 connected to the base 20 can have a window 32. For example, the window 32 can be connected to the sheet metal of the cap 31 by means of a glass solder.

[0041] Depending on the direction in which the signals are converted, a signal conduction direction is defined. In an electro-optical converter such as a laser diode, the signal conduction direction is along the signal conductor 10 from the feedthrough 22 to the laser diode. In order to achieve good reflection attenuation, it is generally particularly preferred, without limitation to the example shown, if the deflection section 5 adjacent to the leg 13 through which the electrical signals flow first has a deflection angle of less than 45°, preferably less than 40°, to the edge, preferably to the outer edge 3 of the leg 13. Which leg 13, 14 the electrical signals flow through first is determined by the signal conduction direction.

[0042] A deflection of the signal conductor 10, as described in this disclosure, can be advantageous, for example, when the electronic component 28 is to be thermally decoupled from the base 20. For this purpose, according to one embodiment, it can be provided that the electronic component 28 is arranged on a pedestal 24, which is cooled by a thermoelectric cooler 26, wherein the carrier 16 with the signal conductor 10 is arranged next to the pedestal 24 and separated from the pedestal 24 by a gap 27. The gap 27 prevents thermal contact with the carrier 16 of the conductor track arrangement 1. However, due to this arrangement, the signal conductor then runs next to the thermoelectric cooling element 26 and the pedestal. The deflection then serves to guide the signal conductor 10 in the direction of the electronic component 28, as shown in the example of the Fig. 6 is evident.

[0043] The gap 27 can then be bridged with a bonding wire 29 attached to one end of the signal conductor 10, in particular to the end of the leg 14. The electrical connection to the electronic component 28 is made, as shown in the example, from the feedthrough 22 to a first leg 13 of the signal conductor 10, via the deflection region 4 to the second leg 14 to the end of the signal conductor 14, which is typically also the end of the second leg 14, and from the end of the signal conductor 14 via the bonding wire 29. The bonding wire 29 can contact the electronic component 29 directly or establish the connection to another conductor track on the pedestal 24. In the Fig. 6 In the example shown, the electronic component 28 is directly connected to the bonding wire 29.

[0044] It will be apparent to those skilled in the art that the conductor track arrangement 1, as well as the base 20 with the conductor track arrangement and the electronic component formed with the base 20 are not limited to the specific examples shown. For example, an additional leg can be connected to one or both legs 13, 14 via a further deflection region. In this way, the signal conductor can be U-shaped, for example, or the additional leg can run laterally offset parallel to the first leg. Furthermore, it is also conceivable to provide two or more signal conductors 10 on the carrier 16. For example, according to one embodiment, these signal conductors 10 can run coplanar on one of the sides of the carrier 16, with a common ground conductor being present on the opposite side.

[0045] Although signal conductors are known from the state of the art in which both edges are curved, their cross-sectional widths of the conductor track do not change during the curvature, as is the case, for example, in Fig. 7 is shown. Due to the constant cross-sectional width, the bend exhibits increased capacitance, which changes the line impedance. This results in a mismatch of the line, which leads to higher signal reflection attenuation in the bend. This is avoided by changing the width of the signal conductor in the deflection region 4, which adapts the capacitance to the required impedance, in particular by reducing it.

[0046] Fig. 8a and 8btherefore show a conductor track arrangement 1 with two curved edges, in which the signal conductor is narrower in the deflection region 4 than at the ends of the signal conductor 10. At the beginning, or at one end and at the other end of the line bend, or of the deflection region 4, in particular of the signal conductor 10, the signal conductor 10 has the width W. The line is thus adapted to the required line impedance at the beginning and at the end. The width W preferably changes continuously over the bend angles of preferably 0° to 90°. The signal conductor preferably has its minimum width W min in the range of half the bend angle between 35° and 60°. In the case of an asymmetrical design of the deflection region, the minimum width W min can, however, also be above 60° or below 35°. As the path continues, the width increases again to reach the width W again at the end at 90°.In this way, a compared to prior art conductor tracks, which are used, for example, in . Fig. 7 As shown, a better transmission behavior at high frequencies is achieved.

[0047] The signal conductor 1, with two curved edges and a narrower width in the deflection area compared to the ends, can be designed in different ways. Preferably, the curvature of the inner edge 3 and the curvature of the outer edge 2 have an elliptical or circular contour. It is therefore conceivable that the center of the circle formed by the inner edge 3 is located closer to the signal conductor than the center of the circle formed by the outer edge 2.

[0048] As in Fig. 8ashown, the circular section formed by the outer edge 2 can be smaller than 90°, or preferably also greater than 90°. Likewise, the angle between the inner side of the outer edge 2 and a line defined by the width of the signal conductor 10 at the beginning of the curvature of the outer edge 2 can have a value of 90° or less. The angle between the inner side of the inner edge 3 and a line defined by the width of the signal conductor 10 at the beginning of the curvature of the inner edge 3 can have a value of 90° or less. It is possible for the beginning of the curvature of the outer edge 2 to be offset in the direction of the length of the signal conductor 10 relative to the beginning of the curvature of the inner edge 3, preferably in such a way that at least the outer edge and / or the inner edge 3 has at least one straight, in particular non-curved, section in the deflection region 4.

[0049] Fig. 8bshows a different geometry of the signal conductor 10, wherein the angle between the inner side of the outer edge 2 and the line defined by the width of the signal conductor 10 at the beginning of the curvature of the outer edge 2 has a value of 90° or more. The circular section formed by the outer edge 2 is then less than 90° or preferably exactly 90°. The angle between the inner side of the inner edge 3 and the line defined by the width of the signal conductor 10 at the beginning of the curvature of the inner edge 3 can have a value of 90° or more. In this case, the circular section formed by the inner edge 3 is greater than 90°, preferably greater than 130°, preferably greater than 180°. It may be conceivable that the beginning of the curvature of the outer edge 2 is offset from the beginning of the curvature of the inner edge 3, preferably in such a way that at least the outer edge and / or the inner edge 3 has a straight, in particular non-curved, section in the deflection region 4.

[0050] In Fig. 9 It is shown how a preferred width W min can be determined in the deflection area 4. The figure shows a construction with a conductor track as shown in Fig. 7is presented, with a constant line width W in the line bend in the deflection area 4. Furthermore, an auxiliary circle 34 is shown. The center point of the auxiliary circle 34 is defined by the fact that the distance of the circle center to the outer contour or edge points 33 of the line bend at the beginning, or one end 35, and at the other end 36 of the bend, or of the deflection area 4, is the same. The two contour points 33 are circled by dashed lines. If the radius R h of the auxiliary circle 34 is greater than the radius of the outer edge 2 of the signal conductor 10, the auxiliary circle 34 cuts off a crescent-shaped area 40 from the line bend. A preferred line bend is now created by subtracting the crescent area 40 from the line bend. The crescent area 40 consists of two circle segments of different radii. The distance between these two circular segments is zero at the angles of curvature 0° and 90° and maximum at the angle of curvature of 45°.This means that at 0° and 90°, the cable bend is not clipped. At the beginning 35° and the end 35° of the deflection area 4, the width W of the signal conductor remains the same or unchanged. However, at a bend angle of 45°, the cable bend is clipped the most. At this angle, the width W min of the signal conductor 10 is preferably minimal.

[0051] Depending on the carrier material, the desired line impedance, and the curve radius of the line bend, a suitable radius R h of the auxiliary circle 34 can be determined through simulations. This typically represents a compromise between the shift in the cutoff frequency of the higher-order waves and the required reflection attenuation. However, it is also conceivable to use an ellipse or a parabola instead of the auxiliary circle 34. However, it is important that the auxiliary surface is formed by a continuous function to avoid abrupt changes and that the outer edge of the signal conductor 10 intersects the auxiliary surface at at least two points. Based on such simulations and their results, the advantage of the reduced width W min of the signal conductor 10 in the deflection region 4 will be demonstrated below.

[0052] Based on the Figs. 8a, 8b and 9It can be seen that a favorable shape of the signal conductor 10 can be obtained without limitation to the specific examples shown if the outer edge and the inner edge represent segments of non-concentric curves, in particular non-concentric circles or ellipses. Accordingly, the curvature, or the curve profile of the inner edge 3 and the curvature of the outer edge each have a center, wherein the center of the curvature of the inner edge 3 and the center of the curvature of the outer edge are arranged offset from one another, in particular so that the curvature of the inner edge 3 and the curvature of the outer edge 2 are formed eccentrically. In particular, the center of the curve of the inner edge 3 can be arranged closer to the signal conductor 10 than the center of the curve of the outer edge 2. This is also the case with both configurations of the Fig. 8This is the case. In the examples, this offset of the centers lies along the angle bisector of the deflection, which, with circular segment-shaped outer and inner edges, leads to a mirror-symmetrical shape of the deflection area, preferably also of the entire signal conductor, with respect to the angle bisector.

[0053] In the Figures 10 , 12 , 14 , 16 and 18 Therefore, the insertion loss and the Figures 11 , 13 , 15 , 17 and 19 the reflection loss of the 90° cable angle known from the state of the art with a 45° bevel 8, as shown in Fig. 1 is shown, as well as the line curvature with constant line width W from Fig. 7The insertion loss and the reflection loss that can be achieved with the inventive design of the curvature of the signal conductor 10 in the deflection region 4, wherein both edges 2, 3 are curved and the width W min of the signal conductor in the deflection region 4 is smaller than the width W at the ends 35, 36 of the deflection region 4, is also shown. For better illustration and comparability of the diagrams, appropriate pictograms have been inserted, showing each of the three aforementioned designs of the signal conductor with which the presented results were achieved. The pictograms correspond to the Figures 1 , 7 and 8 , partial images a, b shown embodiments of the signal conductor 10.

[0054] The Fig. 10 to 15show the variation of the scattering parameters S 21 and S 11 describing the signal attenuation on a transistor outline header (TO header) with a signal line connected to a feedthrough. The inventive line curvature in the Figures 14 and 15 shows significantly better properties at high frequencies than the conduction angle known from the state of the art ( Figs. 10 and 11 ), or curvature with constant line width ( Figs. 12 and 13). In the insertion loss, singular points mark the cutoff frequency for higher-order waves. For the two known deflections of a signal cable, the lower cutoff frequency is approximately 65-70 GHz. For the cable bend with reduced width W min and curved edges 2, 3, the cutoff frequency is advantageously above 80 GHz, or no longer within the measurement range. The cutoff frequency is therefore shifted to significantly higher values ​​by the reduced width W min in the deflection area 4 and the curvature of edges 2, 3, so that the fundamental wave is no longer affected by higher-order waves at higher frequencies, as is possible with state-of-the-art signal cables.

[0055] Since the line bend with a constant trace width W cannot compensate for the increased capacitance of the corner, the overall return loss is greater than that of the 90° line bend with a 45° bevel. However, the line bend with a reduced width W min and curved edges 2, 3 can compensate for the increased capacitance very well and therefore also shows improved return loss compared to the 45° bevel 8 or the constant width. The diagrams show that the line angle with a 45° bevel 8 and the line bends with a constant width can no longer be used for undisturbed signal transmission above the cutoff frequency.

[0056] In order to demonstrate the application range of a signal conductor 10 with improved line curvature with reduced width W min and curved edges 2, 3, the simulation was carried out with two different carrier boards.

[0057] In the Fig. 10 to 15and also the diagrams of the Fig. 16 to 19 The frequency responses of the scattering parameters for the various signal conductor shapes are indicated by lines. The frequency responses for the known arrangement with a 45° bevel are shown with dotted lines, the responses for a curved signal conductor with a constant width are shown with dashed lines, and the responses for a curved signal conductor with a variable width are shown with solid lines. Additionally, the respective curves are marked with pictograms representing the various conductor shapes. Fig. 16 The insertion losses of the simulation results are shown, where the simulation was carried out with a carrier board or a submount with a thickness or height of 0.2 mm. Fig. 17 shows the corresponding results of the reflection loss for the Fig. 16 mentioned properties.

[0058] Fig. 18 shows the insertion loss with a submount with a height of 0.15mm. Fig. 19 shows the corresponding results of the reflection loss for the Fig. 18 mentioned properties.

[0059] The Figs. 16, 17 and 18, 19 The simulations presented differ in the values ​​of the height and thickness of the submount and the width of the signal conductor that are typical for TO applications. Fig. 16 to 19It can be clearly seen that the cutoff frequency for the excitation of higher-order waves with a 45° bevel and a constant conductor track width is already around 70 GHz, whereas the cutoff frequency is between 80 and 100 GHz when using a thinner submount. The cutoff frequency for a signal conductor 10 with a reduced width W min and curved edges 2, 3, however, is significantly higher in all cases. Here, the cutoff frequency is increased by approximately 20 GHz or more. In the case of the thin submount, a very slight kink in the insertion loss can be seen at around 90 GHz, which indicates a cutoff frequency, but which can be minimized to insignificance by appropriately selecting the width W min. Improved values ​​for the return loss are also clearly evident compared to a 45° bevel and a constant conductor track width.

[0060] Fig. 20shows schematically a signal conductor 10 with reduced width W min and curved edges 2, 3 in use with a further electronic component with a socket 20 and its base 21. As electronic component 28, an electronic component, preferably an optoelectronic converter, in particular a laser diode or a light sensor, can be provided, as is also the case in Fig. 6described. The electronic component 28 can be connected, without limitation to the example shown here, to two signal conductors 10, each of which can be electrically connected to a pin for further signal transmission. To achieve good reflection attenuation, it is generally advantageous if one end 35 of the deflection region, or of the signal conductor 10, is electrically coupled to a pin and another end 36 is electrically coupled to the component 28. The deflection typically serves to guide the signal conductor(s) 10 from the pin towards the component 28.

[0061] Preferably, the signal conductors 10 are electrically separated from one another, for example by a gap 27, or decoupled. At least one signal conductor can preferably be electronically connected to the component 28 by at least one bonding wire. Typically, it is provided that the other signal conductor is coupled directly, in particular without a bonding wire, to a terminal of the component. A deflection of the signal conductor 10, as described in this disclosure, can be advantageous, for example, when the electronic component 28 is to be thermally decoupled from the base 20, as is the case in Fig. 6 For this purpose, it can be provided that the component 28 is arranged on a pedestal 24, which is cooled by a thermoelectric cooler 26. However, unlike in Fig. 6It is shown that the electronic component 28 is cooled without a thermoelectric cooler 26 and, in particular, is thermally coupled to the pedestal 24. Furthermore, a submount or a carrier 16 is preferably arranged on the pedestal 24, on the upper side of which the signal conductor(s) 10 are arranged. A ground conductor is arranged on the underside of the carrier 16, in particular with electrical contact to the pedestal 24, for grounding purposes, so that the conductor track arrangement 1 can be designed as a microstrip line or as a CBCPW arrangement.

[0062] The conductor track arrangement 1, or the signal conductor(s) 10, have a deflection region 4, wherein the width W min in the deflection region 4 is at least partially smaller than the width W at at least one of the ends 35, 36 of the deflection region 4. Preferably, the edges 2, 3, in particular the outer 2 and inner edge 3 of at least one signal conductor 10, preferably of both signal conductors 10, are curved at least partially, in particular continuously. The curvature of the inner edge 3 and the curvature of the outer edge 3 are preferably eccentric, so that the radius of the curvature of the outer edge 2 is greater than the radius of the curvature of the inner edge 3. The deflection region 4 can extend from one end to the other end of the signal conductor(s).

[0063] In order to understand the mode of operation and in particular the effect of the conductor track arrangement described above, the formation of higher order waves on a microstrip line, as they occur for example in Fig. 2 and 20 described, briefly explained. Fig. 21shows in three partial images a microstrip line in cross section and the field lines 42 that form between the signal conductor 11 and the ground conductor 11 arranged opposite on the submount 17. The submount 17 has a height h that is small compared to ¼ of the wavelength. For this reason, no higher waves exist in the vertical direction. In the horizontal direction, however, higher order waves can propagate if the width W is on the order of a multiple of half the wavelength (n λ / 2). In this case, further standing waves can form in the transverse direction. Therefore, there is a cut-off frequency above which higher order waves propagate or can exist. Higher order waves can also be excited by disturbances in the signal conductor.

[0064] The microstrip line has an inhomogeneous material filling and therefore does not carry a pure transverse electromagnetic wave (TEM wave). However, the fundamental waves behave almost like a TEM wave over wide frequency ranges and are therefore also referred to as quasi-TEM waves. These can be used effectively for signal transmission. In these fundamental waves, or quasi-TEM waves, the field lines of the electric field (E-field) are directed in the same direction across the cross-section of the signal conductor 10, or across the width of the signal conductor 10, as shown in sub-image (a). The field lines of the higher-order waves, on the other hand, change direction across the width of the signal conductor 10, so that the E-field disappears between such changes of direction. Sub-images (b) and (c) show the field lines of the first two harmonics, or higher-order waves.

[0065] The fundamental wave and all higher-order waves are referred to as eigenwaves of the signal conductor 10. On an undisturbed line, the eigenwaves move independently of one another and do not interfere with each other. In the event of a disturbance, such as a change in direction or a kink in the signal conductor, a coupling of the eigenwaves, i.e., the fundamental waves and the higher-order waves, occurs. This changes the properties of the fundamental wave as soon as a higher-order wave propagates.

[0066] The microstrip line described above has the advantage of being simple in design compared to more complex conductor systems such as CBCPW arrangements, and the properties of the natural waves are significantly influenced by the geometry of the signal conductor 10, in particular by the curvature and width, or cross-section, of the signal conductor 10, as well as by the thickness of the submount, or carrier board, of the signal conductor 10. Without being limited to the examples discussed here, this relationship will be explained using a few example values. The cutoff frequency of the higher-order waves is lower, the greater the width of the signal conductor. If the line impedance is approximately half the usual 50 Ω, i.e. only 25 Ω, with the same carrier board, the 25 Ω line is three times wider than a 50 Ω line.The cutoff frequency for higher order waves is therefore one third lower for a 25 Ω line than for a conventional 50 Ω line.

[0067] As in the Figures 10 to 19 As shown, the cutoff frequency of the higher order waves could be determined by the, particularly in the Figures 8a, b, 9 and 20 presented embodiments are shifted to high frequency values, for example above 80 GHz, so that the fundamental waves, i.e. the signal line, are only slightly disturbed or even not disturbed at all up to frequency values ​​up to 80 GHz, preferably up to 90 GHz, preferably even at values ​​above 100 GHz.

[0068] The invention is defined by the claims. List of reference symbols 1 Conductor track arrangement 2 Outer edge of the signal conductor 10 3 Inner edge of the signal conductor 10 4 Deflection area 5 Deflection section of 2 6 Deflection section of 3 7 Submount 8 Bevel 10 Signal conductor 11 Ground conductor 12 Corner 13, 14 leg 16 carrier 17 Submount 18 gap in 4 20 base 21 Base of 20 22 Implementation 24 podium 26 Thermoelectric cooler 27 gap 28 Electronic component 29 Bonding wire 30 Electronic component 31 cap 32 Window 33 Outer contour points 34 Support group 35 One end of the deflection area 36 Other end of the deflection area 40 Crescent-shaped surface 42 field line α Deflection angle H Thickness of 1 W Width of 10 W min Minimum width of 10 at one end of 1 D 2 × W R h Radius of the auxiliary circle X miter

Claims

1. A conductor track arrangement (1) for high-frequency signals, comprising a substrate (16) and a layer-shaped, flat signal conductor (10) arranged on said substrate (16) and delimited by at least one inner edge (3) and at least one outer edge (2) and extending from one end to another end of the signal conductor (10), with the signal conductor (10) of the conductor track arrangement (1) changing its orientation within a deflection area (4) between said ends and having a minimum width (Wmin), said minimum width (Wmin) in the deflection area (4) of the signal conductor (10) being smaller than the widths (W) at the ends of the signal conductor (10), and the outer edge (2) and inner edge (3) being curved in the deflection area (4), at least in sections thereof, the curvature of the inner edge (3) and the curvature of the outer edge (2) each having a centre; characterized in that the centre of the curvature of the inner edge (3) and the centre of the curvature of the outer edge (2) are offset from one another, so that the curvature of the inner edge (3) and the curvature of the outer edge (2) are shaped eccentrically, and wherein the contour of the outer edge (2) is overall convex and the contour of the inner edge (3) is overall concave in the deflection area.

2. The conductor track arrangement (1) according to any one of the preceding claims, characterized by at least one of the following features: - the curvature of the outer edge (2) and / or of the inner edge (3) is continual, in particular uninterrupted; - the curvature of the outer edge (2) and / or of the inner edge (3) is continuous; - the width of the signal conductor (10) changes continuously within the deflection area (4); - the minimum width (Wmin) of the signal conductor (10) is within the middle third of the deflection area (4), preferably in the middle of the deflection area (4).

3. The conductor track arrangement (1) according to any one of the preceding claims, characterized in that the deflection area (4) extends from one end to the other end of the signal conductor.

4. The conductor track arrangement (1) according to any one of the preceding claims, characterized by any of the following features: - the deflection area (4) is shaped asymmetrically; - the deflection area (4) has a mirror axis along the angle bisector of the deflection area.

5. The conductor track arrangement (1) according to any one of the preceding claims, characterized in that the signal conductor (10) is deflected within the deflection area (4) by an angle ranging from 75° to 105°, preferably by an angle of 90°.

6. The conductor track arrangement (1) according to any one of the preceding claims, characterized in that the conductor track arrangement (1) is in the form of a microstrip line or a coplanar waveguide or a CBCPW arrangement.

7. The conductor track arrangement according to any one of the preceding claims, characterized in that the conductor track arrangement (1) comprises a layer-shaped ground conductor (11) which is arranged opposite the layer-shaped flat signal conductor (10), with at least one of the following features applying to the spacing between the ground conductor (11) and the signal conductor (10): - the spacing is in the range from 0.025 mm to 0.5 mm, preferably in the range from 0.05 mm to 0.4 mm; - the width (W) at one end (35, 36) of the signal conductor (10) is greater than the spacing between the ground conductor (11) and the signal conductor (10) by a factor in the range from 0.5 to 7.5, preferably in the range from 0.6 to 5; - the ratio of the spacing between the signal conductor (10) and the ground conductor (11) to the difference between the width (W) of the signal conductor (10) at one of its ends (35, 36) and the minimum width (Wmin) of the signal conductor (1) has a value in the range from 0.5 to 2; - the conductor track arrangement (1) is designed such that a cut-off frequency, in particular a cut-off frequency for the occurrence of higher order wave modes lies above 60 GHz, preferably above 70 GHz.

8. The conductor track arrangement (1) according to any one of the preceding claims, characterized by at least one of the following features: - the conductor track arrangement (1) is arranged on a submount (17); - the substrate (16) comprises an aluminium nitride ceramic, a ceramic containing aluminium nitride, glass, or glass and ceramic.

9. A header (20) for an electronic module, comprising an electronic component (28) and a conductor track arrangement (1) according to any one of the preceding claims, wherein the header has an electrical feedthrough (22), and wherein both the electronic component (28) and the electrical feedthrough (22) are connected to the signal conductor (10) of the conductor track arrangement (1), so that electrical signals are conducted from the feedthrough (22) via the signal conductor (10) to the component (28).

10. An electronic module (30) in the form of a component comprising a package which encloses an electronic component (28) and the conductor track arrangement (1) according to any one of the preceding claims.