Balun-based differential dual-mode transmission line on artificial surface plasmon chip

Abstract

The invention relates to an artificial surface plasmon on-chip differential dual-mode transmission line based on Balun. The on-chip differential dual-mode transmission line comprises a differential dual-mode transmission line located in the middle, symmetrical Balun structures located at the two ends of the differential dual-mode transmission line and bonding pad structures located on the outer sides of the Balun structures. The differential dual-mode transmission line has three different structures which are respectively four metal strip lines which are parallel to each other and branch knots which are arranged among the metal strip lines. The four metal strip lines are parallel to one another; the cross-layer branch knots are positioned below the metal strip lines; the two pairs of parallel metal strip lines are distributed on different metal layers; and the branches are arranged between the metal lines on the same layer. Transmission of two pairs of differential artificial surface plasmon signals can be supported at the same time, and the differential artificial surface plasmon antenna is suitable for technologies of gallium arsenide, silicon nitride and other III-V chips, other chips, circuit boards and the like, and supports design of a terahertz wave band, a microwave band and a millimeter wave band.

Description

Technical Field

[0001] The present invention is an artificial surface plasmon on-chip differential dual-mode transmission line based on a balun, belonging to the technical field of terahertz, microwave and millimeter wave transmission line design. Background Art

[0002] Surface plasmons are electromagnetic waves that propagate along the surfaces of metals and dielectrics under certain excitation conditions. They can confine electromagnetic field energy to a deep subwavelength range, unconstrained by the diffraction limit. They possess excellent properties such as strong field confinement, short operating wavelength, and high-frequency cutoff. They hold great promise for applications in integrated circuits, communications technology, and sensors. However, natural surface plasmons exist only in the optical wavelength range. To realize surface plasmons at lower frequencies (terahertz, microwave, and millimeter waves), artificial surface plasmons have been proposed.

[0003] A differential signal consists of a pair of signals with equal amplitude and opposite polarity. External interference, typically in the form of common-mode noise, acts simultaneously on both transmission lines. This effectively cancels out electromagnetic interference (EMI) and crosstalk during high-speed and long-distance transmission, reducing signal distortion and improving signal transmission reliability and integrity. Furthermore, the opposite polarity of the two signal lines on a differential transmission line cancels out the radiated electromagnetic fields. The tighter the coupling, the less electromagnetic energy is released to the outside world, helping to meet stringent electromagnetic compatibility (EMC) standards. Differential transmission lines are widely used in high-speed data communications, wireless communication systems, aerospace, and military applications. However, in practice, differential transmission lines require strict impedance matching. Impedance inhomogeneities or sudden changes in the transmission line's impedance can cause signal reflections, compromising signal integrity. Common-mode signals can also be generated, causing electromagnetic interference and reducing the differential transmission line's interference immunity and EMC capabilities. Summary of the Invention

[0004] Technical Problem: The purpose of this invention is to propose a balun-based on-chip differential dual-mode artificial surface plasmon transmission line that can simultaneously support the transmission of two pairs of differential artificial surface plasmon signals. This line is applicable to Group III-V chips such as gallium arsenide and silicon nitride, as well as other chip and circuit board technologies. It can support designs in the terahertz, microwave, and millimeter wave bands.

[0005] Technical solution: The present invention provides an artificial surface plasmon on-chip differential dual-mode transmission line based on a balun, comprising a differential dual-mode transmission line located in the middle, symmetrical balun structures located at both ends of the differential dual-mode transmission line, and a pad structure located outside the balun structure; wherein the differential dual-mode transmission line is composed of four mutually parallel metal strips and a plasmon unit located between the four mutually parallel metal strips, the balun structure includes a lower metal connecting line, a lower metal bending line, an upper metal bending line, and a feed line; the pad structure includes a signal pad, A ground pad, wherein the ground pad includes a ground probe pad, an intermediate layer flat plate, a lower layer flat plate, an upper layer metal through-hole array, a lower layer metal through-hole array, and a rectangular back-gold through-hole; the signal pad and the ground pad are arranged at intervals, that is, the ground pad, signal pad, ground pad, signal pad, and ground pad are arranged in sequence; the signal pad is connected to one end of the lower layer metal bending line through the lower layer metal connecting line, and the other end port of the lower layer metal bending line is suspended; the ground pad is connected to one end of the feeder line through the upper layer metal bending line, and the other end of the feeder line is connected to the metal strip line.

[0006] The lower metal connecting line is connected to the lower metal bending line, and the lower metal bending line is not contact-coupled with the upper metal bending line; the lower metal bending line is in the shape of "]", and the upper metal bending line is in the shape of "┐"; the feed line is two "┑" right-angle shapes connected head to tail.

[0007] The plasmon unit located between the four mutually parallel metal strips has a first structure that is a zigzag artificial surface plasmon unit; among the four mutually parallel metal strips, multiple zigzag structures are symmetrically arranged between the first parallel line and the second parallel line, one end of the upper zigzag structure is respectively connected to the first parallel line, and one end of the lower zigzag structure is respectively connected to the second parallel line; multiple zigzag structures are symmetrically arranged between the third parallel line and the fourth parallel line, one end of the upper zigzag structure is respectively connected to the third parallel line, and one end of the lower zigzag structure is respectively connected to the fourth parallel line.

[0008] The second structure of the plasmon unit located between the four mutually parallel metal strips is a cross-layer zigzag artificial surface plasmon unit; among the four mutually parallel metal strips, multiple zigzag structures are connected below each parallel line, and one end of the zigzag structure is connected to the parallel line above.

[0009] The third structure of the plasmon unit located between four mutually parallel metal strips is a double-layer artificial surface plasmon unit; in the upper metal strip, two rows of upper zigzag artificial surface plasmon units are symmetrically arranged between two parallel lines, wherein one end of the upper zigzag structure in one row is respectively connected to the first parallel line, and one end of the upper zigzag structure in the other row is respectively connected to the second parallel line; in the lower metal strip, two rows of L-shaped structures are symmetrically arranged between the two parallel lines, wherein one end of the L-shaped structure in one row is respectively connected to the first parallel line in the lower metal strip, and one end of the L-shaped structure in the other row is respectively connected to the second parallel line in the lower metal strip.

[0010] The upper-layer feeder and the upper-layer metal strip line are located on the same layer, one end of the upper-layer feeder is connected to the upper-layer metal bending line of the balun structure, and the other end is connected to the upper-layer metal strip line; the lower-layer feeder and the lower-layer metal strip line are located on the same layer, one end of the lower-layer feeder is connected to the upper-layer metal bending line of the balun structure through a metal through-hole, and the other end is connected to the lower-layer metal strip line.

[0011] The ground probe pad is connected to the middle plate through an upper metal through-hole array, connected to the lower plate through a lower metal through-hole array, and connected to the metal ground structure through a rectangular back-gold through-hole.

[0012] Beneficial effects: The balun-based artificial surface plasmon on-chip differential dual-mode transmission line of the present invention can simultaneously support the transmission of two pairs of differential artificial surface plasmon signals, and is applicable to III-V chips such as gallium arsenide and silicon nitride, as well as other chips and circuit boards and other technologies. It can support designs in the terahertz band, microwave band, and millimeter wave band. The design structure of the present invention is simple, and by proportionally reducing and enlarging the structure, it can support designs in the terahertz band, microwave band, and millimeter wave band, and has good development prospects in the fields of high throughput, low crosstalk, and multimode communications. It has the following specific advantages:

[0013] 1. The balun-based artificial surface plasmon on-chip differential dual-mode transmission line designed in the present invention can simultaneously support the transmission of two pairs of odd-mode artificial surface plasmon signals.

[0014] 2. The feeding structure designed in the present invention can well transmit differential mode signals with equal amplitudes and opposite phases, providing good signal input for differential dual-mode transmission lines.

[0015] 3. The artificial surface plasmon on-chip differential dual-mode transmission line based on the balun designed in the present invention has an extremely small electrical size of approximately 0.32λ*0.12λ*0.038λ.

[0016] 4. The balun structure designed in the present invention can well balance voltage and current, suppress common-mode current, and perform impedance conversion, which is beneficial to signal transmission.

[0017] 5. The present invention can adjust the scattering parameters of the differential dual-mode transmission line, including bandwidth, center frequency, insertion loss, return loss, amplitude, etc., by changing the structural size parameters of the balun structure.

[0018] 6. The present invention can adjust the dispersion properties of artificial surface plasmons by changing the structural size parameters of the artificial surface plasmon units.

[0019] 7. The artificial surface plasmon on-chip differential dual-mode transmission line based on the balun designed in the present invention can concentrate most of the electric field energy near the metal surface of the transmission line, reflecting the strong field binding ability of the artificial surface plasmon.

[0020] 8. The present invention has a simple design structure. By proportionally reducing and enlarging the balun structure and the transmission line structure, it can support the design work of the terahertz band, microwave band and millimeter wave band, and has good development prospects in many fields.

[0021] 9. The differential dual-mode transmission line of the present invention has a variety of designs and can be selected and replaced, and has wide practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a top view of the first structure of the artificial surface plasmon on-chip differential dual-mode transmission line based on the balun, which includes: dielectric glue 1, metal strip line 4, signal pad 5, ground pad 6, lower metal connecting line 101, lower metal bending line 102, upper metal bending line 103, feed line 104, and zigzag artificial surface plasmon unit 410.

[0023] Figure 2 This is a top view of the second structure of the artificial surface plasmon on-chip differential dual-mode transmission line based on the balun, which includes: dielectric glue 1, metal strip line 4, signal pad 5, ground pad 6, lower metal connecting line 101, lower metal bending line 102, upper metal bending line 103, feed line 104, and cross-layer zigzag artificial surface plasmon unit 420.

[0024] Figure 3 This is a top view of the third structure of the artificial surface plasmon on-chip differential dual-mode transmission line based on the balun, which includes: dielectric glue 1, metal strip line 4, signal pad 5, ground pad 6, lower metal connecting line 101, lower metal bending line 102, upper metal bending line 103, upper feed line 1041, lower feed line 1042, and double-layer artificial surface plasmon unit 430.

[0025] Figure 4 It is a top view of the transmission line structure of the first structure, which includes: a metal strip line 4 and a broken-line artificial surface plasmon unit 410.

[0026] FIG5( a ) is a top view of a transmission line structure of the second structure, which includes: a metal strip line 4 and a cross-layer zigzag-line artificial surface plasmon unit 420 .

[0027] FIG5( b ) is a side view of a transmission line of the second structure, which includes: a metal strip line 4 and a cross-layer zigzag-line artificial surface plasmon unit 420 .

[0028] FIG6( a ) is a top view of a transmission line structure of the third structure, which includes: a metal strip line 4 and a double-layer artificial surface plasmon unit 430 .

[0029] FIG6( b ) is a top view of the upper structure of the transmission line of the third structure, which includes: an upper metal strip line 41 and an upper zigzag artificial surface plasmon unit 431 .

[0030] FIG6( c ) is a top view of the lower structure of the transmission line of the third structure, which includes: a lower metal strip line 42 and a lower L-shaped artificial surface plasmon unit 432 .

[0031] Figure 7(a) shows the transmission and reflection coefficients of the first structure of a balun-based on-chip differential dual-mode transmission line. Here, S21 and S43 are the transmission coefficients for ports 1 and 2, and ports 3 and 4, respectively, and they coincide with each other; S11 and S33 are the reflection coefficients for ports 1 and 3, respectively, and they coincide with each other.

[0032] Figure 7(b) shows the port crosstalk coefficients for the first structure of a balun-based on-chip differential dual-mode transmission line. Here, S13 and S31 are the crosstalk coefficients for ports 1 and 3, and they overlap; S23 and S41 are the crosstalk coefficients for ports 3 and 2, and ports 1 and 4, respectively, and they overlap.

[0033] Figure 8(a) shows the transmission and reflection coefficients of the second structure of a balun-based on-chip differential dual-mode transmission line. Here, S21 and S43 are the transmission coefficients for ports 1 and 2, and ports 3 and 4, respectively, and they coincide with each other; S11 and S33 are the reflection coefficients for ports 1 and 3, respectively, and they coincide with each other.

[0034] Figure 8(b) shows the port crosstalk coefficients for the second structure of a balun-based on-chip differential dual-mode transmission line. Here, S13 and S31 are the crosstalk coefficients for the first and third ports, and they overlap; S23 and S41 are the crosstalk coefficients for the third and second ports, and the fourth port, respectively, and they overlap.

[0035] Figure 9(a) shows the transmission and reflection coefficients of the third structure of a balun-based on-chip differential dual-mode transmission line. Here, S21 and S43 are the transmission coefficients for ports 1 and 2, and ports 3 and 4, respectively, and they coincide with each other; S11 and S33 are the reflection coefficients for ports 1 and 3, respectively, and they coincide with each other.

[0036] Figure 9(b) shows the port crosstalk coefficients for the third configuration of a balun-based on-chip differential dual-mode transmission line. Here, S13 and S31 are the crosstalk coefficients for ports 1 and 3, and they overlap; S23 and S41 are the crosstalk coefficients for ports 3 and 2, and ports 1 and 4, respectively, and they overlap.

[0037] Figure 10(a) is a top view of the balun's upper structure, where the black portion is the upper structure and the gray portion is the lower structure, which are not in contact with each other.

[0038] Figure 10(b) shows a top view of the balun's lower structure, where the black portion is the lower structure and the gray portion is the upper structure, with no contact or coupling between them.

[0039] FIG11( a ) is a side view of a multi-pad structure.

[0040] FIG11( b ) is a cross-sectional view of the ground pad. DETAILED DESCRIPTION

[0041] The on-chip differential dual-mode transmission line includes a differential dual-mode transmission line located in the middle, a balun structure symmetrically located at both ends of the differential dual-mode transmission line, and a pad structure located outside the balun structure; wherein the differential dual-mode transmission line is composed of four mutually parallel metal strip lines 4 and a plasmon unit located between the four mutually parallel metal strip lines 4, the balun structure includes a lower metal connecting line 101, a lower metal bending line 102, an upper metal bending line 103, and a feed line 104; the pad structure includes The signal pad 5 and the ground pad 6 are arranged at intervals, that is, the ground pad 6, the signal pad 5, the ground pad 6, the signal pad 5, the ground pad 6, the signal pad 5, and the ground pad 6 are arranged in sequence; the signal pad 5 is connected to one end of the lower metal bending line 102 through the lower metal connecting line 101, and the other end of the lower metal bending line 102 is suspended; the ground pad 6 is connected to one end of the feed line 104 through the upper metal bending line 103, and the other end of the feed line 104 is connected to the metal strip line 4.

[0042] The lower metal connecting line 101 of the balun structure is connected to the lower metal bending line 102, and the lower metal bending line 102 is non-contact coupled with the upper metal bending line 103; the lower metal bending line 102 is in the shape of "]", and the upper metal bending line 103 is in the shape of "┐"; the feed line 104 is two "┑" right-angle shapes connected head to tail; the width of the lower metal connecting line 101, the lower metal bending line 102, the upper metal bending line 103, and the feed line 104 are all 8um, and the thickness is 1.5um, and the coupling spacing between the lower metal bending line 102 and the upper metal bending line 103 is 1um.

[0043] The first structure of the plasmon unit located between the four mutually parallel metal strip lines 4 is a zigzag artificial surface plasmon unit 410; in the four mutually parallel metal strip lines 4, a plurality of zigzag structures are symmetrically arranged between the first parallel line and the second parallel line, one end of the upper zigzag structure is respectively connected to the first parallel line, and one end of the lower zigzag structure is respectively connected to the second parallel line; a plurality of zigzag structures are symmetrically arranged between the third parallel line and the fourth parallel line, one end of the upper zigzag structure is respectively connected to the third parallel line, and one end of the lower zigzag structure is respectively connected to the fourth parallel line; differential The dual-mode transmission line includes 13 zigzag-shaped artificial surface plasmon units 410, each zigzag-shaped artificial surface plasmon unit 410 is 86 μm wide and 64 μm long, and includes four metal strip lines 4 with a line width of 4 μm and four connected zigzag-shaped structures. Each zigzag-shaped structure has a metal line width of 4 μm and includes five "gate"-shaped square wave structures on the same layer. Increasing the width of the metal strip line 4, increasing the number of "gate"-shaped square wave structures, and increasing the number of zigzag-shaped structures will reduce the cutoff frequency of the differential dual-mode transmission line and enhance the field binding ability of the metal surface of the zigzag-shaped artificial surface plasmon unit 410.

[0044] The second structure of the plasmon unit located between the four mutually parallel metal strip lines 4 is a cross-layer zigzag artificial surface plasmon unit 420; in the four mutually parallel metal strip lines 4, a plurality of zigzag structures are connected below each parallel line, and one end of the zigzag structure is respectively connected to the parallel line above; the differential dual-mode transmission line includes 15 cross-layer zigzag artificial surface plasmon units 420, each cross-layer zigzag artificial surface plasmon unit 420 is 40.5um wide and 48um long, including four line widths The metal strip line 4 is 4.5um and is connected to four zigzag structures. The metal line width of each zigzag structure is 4.5um, and it contains three cross-layer "gate"-shaped square wave structures. The cross-layer structures are connected by rectangular metal through-holes with a side length of 1.5um. Increasing the width of the metal strip line 4, increasing the number of "gate"-shaped square wave structures, increasing the number of zigzag structures, and increasing the number of cross-layer layers of the zigzag structure will reduce the cutoff frequency of the differential dual-mode transmission line, and enhance the field binding ability of the metal surface of the cross-layer zigzag artificial surface plasmon unit 420.

[0045] The third structure of the plasmon unit located between the four mutually parallel metal strip lines 4 is a double-layer artificial surface plasmon unit 430; in the upper metal strip line 41, two rows of upper zigzag artificial surface plasmon units 431 are symmetrically arranged between the two parallel lines, wherein one end of the upper zigzag structure of one row is respectively connected to the first parallel line, and one end of the upper zigzag structure of the other row is respectively connected to the second parallel line; in the lower metal strip line 42, two rows of L-shaped structures 432 are symmetrically arranged between the two parallel lines, wherein one end of the L-shaped structure of one row is respectively connected to the first parallel line in the lower metal strip line, and one end of the L-shaped structure of the other row is respectively connected to the second parallel line in the lower metal strip line; the differential dual-mode transmission line includes 29 double-layer artificial surface plasmon units. Unit 430, each double-layer artificial surface plasmon unit 430 is 24um wide and 24um long, and includes four metal strip lines 4 with a width of 2um and a connected upper zigzag structure and a lower L-shaped structure. The metal line width of the upper zigzag structure and the lower L-shaped structure is 2um. Each upper zigzag structure contains three "gate"-shaped square wave structures of the same layer, and the long arm of the lower L-shaped structure is parallel to the connected metal strip line; increasing the width of the upper metal strip line 41, increasing the number of "gate"-shaped square wave structures, increasing the number of upper zigzag structures, increasing the width of the lower metal strip line 42, increasing the length of the long arm of the L-shaped structure, and increasing the number of L-shaped structures will reduce the cutoff frequency of the differential dual-mode transmission line and enhance the field binding ability of the metal surface of the differential dual-mode transmission line.

[0046] The upper-layer feed line 1041 and the upper-layer metal strip line 41 are located on the same layer, one end of the upper-layer feed line 1041 is connected to the upper-layer metal bending line 103 of the balun structure, and the other end is connected to the upper-layer metal strip line 41; the lower-layer feed line (1042) and the lower-layer metal strip line 42 are located on the same layer, one end of the lower-layer feed line 1042 is connected to the upper-layer metal bending line 103 of the balun structure through a metal through-hole, and the other end is connected to the lower-layer metal strip line 42.

[0047] The ground probe pad 61 is connected to the middle plate 62 through the upper metal through-hole array 64, connected to the lower plate 63 through the lower metal through-hole array 65, and connected to the metal ground structure 3 through the rectangular back-gold through-hole 66; the ground probe pad 61 and the middle plate 62 are rectangular parallelepipeds with a side length of 60um and a height of 1.5um, the lower plate 63 is a rectangular parallelepiped with a side length of 60um and a height of 1um, the upper metal through-hole array 64 includes 14×14 rectangular parallelepipeds with a side length of 2um and a height of 1um, the lower metal through-hole array 65 includes 15×15 rectangular parallelepipeds with a side length of 2um and a height of 1um, and the rectangular back-gold through-hole 66 is a rectangular parallelepiped with a side length of 20um and a height of 80um; the pad meets the physical processing test standards.

[0048] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A balun-based artificial surface plasmon on-chip differential dual-mode transmission line, characterized in that: The on-chip differential dual-mode transmission line comprises a differential dual-mode transmission line located in the middle, symmetrical balun structures located at both ends of the differential dual-mode transmission line, and a pad structure located outside the balun structure; wherein the differential dual-mode transmission line is composed of four mutually parallel metal strip lines (4) and a plasmon unit located between the four mutually parallel metal strip lines (4); the balun structure comprises a lower metal connecting line (101), a lower metal bending line (102), an upper metal bending line (103), and a feed line (104); the pad structure comprises a signal pad (5) and a ground pad (6); wherein the ground pad (6) comprises a ground probe pad (61), an intermediate layer flat plate (62), and a lower layer flat plate. (63), an upper metal through-hole array (64), a lower metal through-hole array (65), and a rectangular back-gold through-hole (66); the signal pad (5) and the ground pad (6) are arranged at intervals, that is, the ground pad (6), the signal pad (5), the ground pad (6), the signal pad (5), and the ground pad (6) are arranged in sequence; the signal pad (5) is connected to one end of the lower metal bending line (102) through the lower metal connecting line (101), and the other end of the lower metal bending line (102) is suspended; the ground pad (6) is connected to one end of the feed line (104) through the upper metal bending line (103), and the other end of the feed line (104) is connected to the metal strip line (4).

2. The balun-based artificial surface plasmon on-chip differential dual-mode transmission line according to claim 1, characterized in that: The lower metal connection line (101) is connected to the lower metal bending line (102), and the lower metal bending line (102) is non-contact coupled with the upper metal bending line (103); the lower metal bending line (102) is in the shape of "]", and the upper metal bending line (103) is in the shape of "┐"; the feed line (104) is in the shape of two "┑" right angles connected head to tail.

3. The balun-based artificial surface plasmon on-chip differential dual-mode transmission line according to claim 1, characterized in that: The first structure of the plasmon unit located between the four mutually parallel metal strip lines (4) is a zigzag-line artificial surface plasmon unit (410); in the four mutually parallel metal strip lines (4), a plurality of zigzag-line structures are symmetrically arranged between the first parallel line and the second parallel line, one end of the upper zigzag-line structure is respectively connected to the first parallel line, and one end of the lower zigzag-line structure is respectively connected to the second parallel line; and a plurality of zigzag-line structures are symmetrically arranged between the third parallel line and the fourth parallel line, one end of the upper zigzag-line structure is respectively connected to the third parallel line, and one end of the lower zigzag-line structure is respectively connected to the fourth parallel line.

4. The balun-based artificial surface plasmon on-chip differential dual-mode transmission line according to claim 1, characterized in that: The second structure of the plasmon unit located between the four mutually parallel metal strip lines (4) is a cross-layer folded-line artificial surface plasmon unit (420); in the four mutually parallel metal strip lines (4), a plurality of folded-line structures are connected below each parallel line, and one end of the folded-line structure is respectively connected to the parallel line above.

5. The balun-based artificial surface plasmon on-chip differential dual-mode transmission line according to claim 1, characterized in that: The third structure of the plasmon unit located between four mutually parallel metal strip lines (4) is a double-layer artificial surface plasmon unit (430); in the upper metal strip line (41), two rows of upper layer folded line artificial surface plasmon units (431) are symmetrically arranged between two parallel lines, wherein one end of the upper layer folded line structure of one row is respectively connected to the first parallel line, and one end of the upper layer folded line structure of the other row is respectively connected to the second parallel line; in the lower metal strip line (42), two rows of L-shaped structures (432) are symmetrically arranged between the two parallel lines, wherein one end of the L-shaped structure of one row is respectively connected to the first parallel line of the lower metal strip line, and one end of the L-shaped structure of the other row is respectively connected to the second parallel line of the lower metal strip line.

6. The balun-based artificial surface plasmon on-chip differential dual-mode transmission line according to claim 5, characterized in that: The upper layer feed line (1041) and the upper layer metal strip line (41) are located in the same layer, one end of the upper layer feed line (1041) is connected to the upper layer metal bending line (103) of the balun structure, and the other end is connected to the upper layer metal strip line (41); the lower layer feed line (1042) and the lower layer metal strip line (42) are located in the same layer, one end of the lower layer feed line (1042) is connected to the upper layer metal bending line (103) of the balun structure through a metal through hole, and the other end is connected to the lower layer metal strip line (42).

7. The balun-based artificial surface plasmon on-chip differential dual-mode transmission line according to claim 1, characterized in that: The ground probe pad (61) is connected to the middle plate (62) via an upper metal through-hole array (64), connected to the lower plate (63) via a lower metal through-hole array (65), and connected to the metal ground structure (3) via a rectangular back-gold through-hole (66).

Images