Terahertz transmission wave modulator based on multi-layer microstructure heterogeneous integration

Abstract

The invention relates to a terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration. The terahertz transmission wave modulator comprises a metal radiation layer, a substrate material, a metal ground layer, an insulating material, a direct current wiring layer, a resin material and a metal receiving layer which are sequentially arranged from top to bottom, the metal radiation layer comprises two diodes; when a terahertz incident wave of which the electric field direction is parallel to the transverse central axis of the metal receiving layer enters the metal receiving layer, a direct current bias voltage signal generated by the direct current wiring layer is transmitted to the two diodes of the metal radiation layer so as to control the conduction state switching of the two diodes; and the amplitude and phase of the terahertz transmission wave emitted by the metal radiation layer are subjected to 1-bit modulation. The terahertz modulator is diversified in regulation and control mode and excellent in performance, can play an important role in terahertz application fields such as tracking and pointing communication, radar perception and object imaging, and has a wide application prospect.

Description

Technical Field

[0001] This application relates to the field of terahertz, and more specifically, to a terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration. Background Technology

[0002] Terahertz waves refer to electromagnetic waves with a frequency range of 0.1 to 10 THz. Currently, the spectrum resources of the microwave and millimeter wave bands are being exhausted, and the world is stepping up the development of spectrum resources in the terahertz band. Terahertz communication has become one of the key technologies for 6G communication and is of great significance for building a 6G integrated air-space-ground communication network.

[0003] Intelligent metasurfaces or metamaterials, which etch artificial microstructures onto various substrate materials, essentially act as modulators for spatial electromagnetic waves. They transfer the modulation function from the waveguide region of the radio frequency channel to the spatial electromagnetic radiation region, effectively alleviating the amplitude and phase modulation pressure of active radio frequency channels. Especially in the terahertz band, when active channels face technical bottlenecks such as high power consumption and difficult integration, terahertz modulators based on intelligent metasurfaces greatly reduce the complexity of terahertz systems and are a core device for realizing terahertz communication, radar, and imaging systems.

[0004] The main types of terahertz modulators are amplitude modulators and terahertz reflected wave phase modulators. Amplitude modulators primarily use external lasers or DC power supplies to change the conductivity or Fermi level of the loaded material, such as vanadium dioxide, graphene, liquid crystal, germanium-antimony-tellurium, and indium gallium-zinc oxide, to control the amplitude of terahertz transmission or reflection. Terahertz phase modulators mainly achieve phase control through liquid crystals, graphene, vanadium dioxide, CMOS, and HEMT transistors. However, most existing terahertz modulators are based on etching metal microstructures on a single-layer dielectric and loading phase change materials to achieve amplitude or phase control. These modulators suffer from technical drawbacks such as high electromagnetic losses, reflection or transmission amplitudes below 0.7 dB, amplitude modulation depths of less than 10 dB, and phase control ranges of less than 180°. Summary of the Invention

[0005] To overcome at least one deficiency in the prior art, this application provides a terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration.

[0006] A terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration includes: a metal radiating layer, a substrate material, a metal ground layer, an insulating material, a DC trace layer, a resin material, and a metal receiving layer arranged sequentially from top to bottom; the metal radiating layer includes two diodes; When a terahertz incident wave with an electric field direction parallel to the transverse central axis of the metal receiving layer is incident on the metal receiving layer, the DC bias voltage signal generated by the DC trace layer is transmitted to the two diodes of the metal radiating layer to control the switching of the conduction state of the two diodes, so that the amplitude and phase of the terahertz transmitted wave emitted by the metal radiating layer are modulated by 1 bit.

[0007] In one embodiment, the metal radiating layer is deposited on the upper surface of the substrate material, and the material further includes a first metal radiating patch, a second metal radiating patch, and a metal square piece; the two diodes are the first diode and the second diode, respectively. The first metal radiating patch and the second metal radiating patch are symmetrically distributed about the center of the substrate material; the metal square plate is located at the center of the substrate material; the first diode is located between the first metal radiating patch and the metal square plate, and the second diode is located between the second metal radiating patch and the metal square plate. The cathode of the first diode is connected to the first metal radiating patch, and the anode of the first diode is connected to the metal square plate. The cathode of the second diode is connected to the metal square plate, and the anode of the second diode is connected to the second metal radiating patch.

[0008] In one embodiment, a DC trace layer is laid on the lower surface of the insulating material, including DC traces, matching microstrip lines, and fan-shaped stubs; The length of the DC trace is parallel to the longitudinal side length of the insulating material. The end of the DC trace is connected to the matching microstrip line. A fan-shaped stub with a right angle is connected to each side of the matching microstrip line. The matching microstrip line and the fan-shaped stub are used to isolate the DC bias voltage signal from the terahertz transmitted wave.

[0009] In one embodiment, a metal receiving layer is laid on the lower surface of the resin material, including a first rectangular metal receiving patch and a second rectangular metal receiving patch. The first rectangular metal receiving patch and the second rectangular metal receiving patch have equal longitudinal lengths but unequal transverse lengths. The first rectangular metal receiving patch and the second rectangular metal receiving patch are connected by a narrow metal patch to form an H-shaped microstructure.

[0010] In one embodiment, a first grounding metal blind via is provided at the center of the first metal radiating patch, and a second grounding metal blind via is provided at the center of the second metal radiating patch. The first and second grounding metal blind vias penetrate through the substrate material and are connected downward to the metal ground layer. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration also has a central metal via, which penetrates the substrate material, the metal ground layer, the insulating material and the resin material, and is connected to the metal square sheet and the metal receiving layer above and below, respectively; a concentric isolation ring is set in the metal ground layer at the position through which the central metal via passes. A DC-powered blind via is provided on the metal receiving layer. The DC-powered blind via penetrates the resin material and is connected to the DC trace layer and the metal receiving layer above and below, respectively. The DC bias voltage signal generated by the DC trace layer is transmitted to the central metal via through the DC-powered blind via, and then reaches the two diodes through the central metal via.

[0011] In one embodiment, the DC power supply blind hole is located on the right side of the transverse central axis of the second rectangular metal receiving patch, or at the center of the first rectangular metal receiving patch.

[0012] In one embodiment, the central metal through-hole penetrates the second rectangular metal receiving patch, and the distance between the center of the central metal through-hole and the left side of the second rectangular metal receiving patch is... x Satisfy: 0 < x ≤265um.

[0013] In one embodiment, each diode operates in the terahertz band and is a Schottky switching diode, a Schottky varactor diode, a PIN diode, or a high electron mobility transistor.

[0014] In one embodiment, the terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration uses no fewer than three types of materials. The substrate material is a semiconductor material or a dielectric material. Semiconductor materials include gallium arsenide, gallium nitride, and silicon, while dielectric materials include quartz and ceramics. The insulating material is a dielectric material with insulating properties, including polycrystalline silicon dioxide; The resin material is a high-performance polymer dielectric material, which includes benzocyclobutene resin; The metal ground layer, metal radiation layer, DC trace layer, and metal receiving layer are all made of gold.

[0015] In one embodiment, the thickness h1 of the substrate material satisfies: 50um ≤ h1 ≤ 127um; The thickness h2 of the insulating material satisfies: 1µm ≤ h2 ≤ 10µm; The thickness h3 of the resin material satisfies: h3≤20um.

[0016] The thickness t of the metal ground layer, metal radiation layer, DC trace layer, and metal receiving layer satisfies: t≤1um.

[0017] In one embodiment, the side length of the terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration p Satisfies: 620um≤ p ≤720um, side length of the metal square sheet a Satisfy: 20um≤ a ≤200um; The width of each diode mounting area is [missing information]. b、 The lengths of the first and second metal radiating patches are: l 1, width is w 1. Constraints exist: p -(2 w 1+ a +2 b ≥20um, p - l 1≥20um.

[0018] Compared with the prior art, this application has the following beneficial effects: 1. This application achieves low transmission loss and a transmittance of over 80% by etching multilayer metal microstructures on the surface of various substrate materials with excellent performance in the terahertz frequency band and loading diode electrically tuned devices as electromagnetic path switches.

[0019] 2. This application can achieve two modulation effects. The first is phase modulation, where when the two diodes switch their conduction states, the phase difference of the transmitted wave within the effective bandwidth reaches 180 degrees, and the transmission amplitude remains above 80%, achieving 1-bit phase modulation with low transmission loss. The second is amplitude-phase joint modulation, where when the two diodes switch their conduction states, the amplitude of the terahertz transmitted wave within the effective bandwidth switches between below 10% and above 80%, with an amplitude modulation depth exceeding 11dB, while the phase difference of the transmitted wave exceeds 100 degrees. Therefore, this modulator has diverse modulation modes and significant technical advantages.

[0020] 3. This application is based on the existing domestic three-dimensional heterogeneous integration technology level, and all dimensions meet the production standards of the process line, making it easy to prepare, test and launch to the market. Attached Figure Description

[0021] This application can be better understood by referring to the description given below in conjunction with the accompanying drawings, which, together with the detailed description below, are incorporated in and form part of this specification. In the drawings: Figure 1 A three-dimensional structural schematic diagram of a terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration is shown. Figure 2 A detailed schematic diagram of a terahertz transmission wave modulator based on heterogeneous integration of multilayer microstructures is shown. Figure 3 A schematic diagram of the longitudinal cross-section of a terahertz transmission wave modulator based on heterogeneous integration of multilayer microstructures is shown. Figure 4The cross-sectional schematic diagrams of each metal microstructure layer and the annotation diagram of key dimensions of the terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration are shown. Among them, (a) is the cross-sectional schematic diagram of the metal radiating layer and the annotation diagram of key dimensions, (b) is the cross-sectional schematic diagram of the metal ground layer and the annotation diagram of key dimensions, (c) is the cross-sectional schematic diagram of the DC trace layer and the annotation diagram of key dimensions, and (d) is the cross-sectional schematic diagram of the metal receiving layer and the annotation diagram of key dimensions. Figure 5 The diagram shows the equivalent connection diagram of the diodes used in the terahertz transmission wave modulator structure based on multilayer microstructure heterogeneous integration and the equivalent model diagram in the on-off state. (a) is the equivalent connection diagram of the diodes, and (b) is the equivalent model diagram of the diodes in the on-off state.

[0022] Figure 6 The transmission amplitude and transmission phase results of Embodiment 1 of the terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration are shown. (a) is the transmission rate of the terahertz wave as a function of frequency when the two diodes of Embodiment 1 are turned on in a time-division manner, corresponding to State 0 and State 1. (b) is the phase of the transmitted electromagnetic wave as a function of frequency in State 0 and State 1.

[0023] Figure 7 The transmission amplitude and transmission phase results of Embodiment 2 of the terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration are shown. Among them, (a) is the transmission rate of the terahertz wave as a function of frequency when the two diodes are turned on in a time-division manner in Embodiment 2, corresponding to State 0 and State 1. (b) is the phase of the transmitted electromagnetic wave as a function of frequency in State 0 and State 1 in Embodiment 2.

[0024] Figure label: 1—Substrate material, 2—Metal ground layer, 3—Insulating material, 4—Resin material, 5—First grounding metal blind via, 6—Second grounding metal blind via, 7—Central metal via, 8—DC power supply blind via, 9—First metal radiating patch, 10—Second metal radiating patch, 11—Metal square patch, 12—First diode, 13—Second diode, 14—DC trace, 15—Matching microstrip line, 16—Fan-shaped stub, 17—Second rectangular metal receiving patch, 18—First rectangular metal receiving patch, 19—Narrow metal patch, 20—Concentric isolation ring, 21—Metal radiating layer, 22—Metal receiving layer, 23—DC trace layer. Detailed Implementation

[0025] Exemplary embodiments of the present application will be described below with reference to the accompanying drawings. For clarity and brevity, not all features of the actual embodiments are described in the specification. However, it should be understood that many embodiment-specific decisions can be made in the development of any such actual embodiment to achieve the developer’s specific objectives, and these decisions may vary as the embodiments differ.

[0026] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the device structure closely related to the solution according to this application is shown in the accompanying drawings, while other details that are not closely related to this application are omitted.

[0027] It should be understood that this application is not limited to the described embodiments by virtue of the following description with reference to the accompanying drawings. In this document, embodiments may be combined with each other, features may be substituted or borrowed between different embodiments, and one or more features may be omitted in one embodiment, where feasible.

[0028] This application discloses a terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration, comprising a multilayer metal microstructure, various substrate materials with excellent performance in the terahertz frequency band, and a diode-tunable device. The modulator is fabricated using various heterogeneous integration processes, including optical etching, chemical vapor deposition, metallization sputtering and electroplating, epitaxial growth, and micro-assembly, achieving low-loss, stable, and electrically controlled flexible modulation of terahertz transmission waves based on multilayer microstructure heterogeneous integration. This application fully utilizes the low-loss characteristics of the selected heterogeneous materials in the terahertz frequency band and the advantages of fast diode-tunable response and low electromagnetic loss, performing three-dimensional heterogeneous integration of the etched metal microstructure and various substrate materials for the switching diode. By digitally encoding and controlling the diode's on / off state, it achieves 1-bit phase modulation and amplitude-phase joint 1-bit modulation with a terahertz wave transmittance exceeding 80%. This versatile and high-performance terahertz transmission wave modulator can play an important role in terahertz applications such as tracking communication, radar sensing, and object imaging, and has broad application prospects.

[0029] This application provides a terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration. Figure 1 A three-dimensional structural schematic diagram of a terahertz transmission wave modulator based on heterogeneous integration of multilayer microstructures is shown. (See attached diagram) Figure 1 The modulator is composed of a multilayer metal microstructure and various heterogeneous materials. The multilayer metal microstructure is dispersed and laid on the surface of different materials through optical etching process, including: a metal radiating layer 21, a substrate material 1, a metal ground layer 2, an insulating material 3, a DC trace layer 23, a resin material 4, and a metal receiving layer 22 arranged from top to bottom; the metal radiating layer 21 includes two diodes.

[0030] When a terahertz incident wave with an electric field direction parallel to the transverse central axis of the metal receiving layer 22 is incident on the metal receiving layer 22, the DC bias voltage signal generated by the DC trace layer 23 is transmitted to the two diodes of the metal radiating layer 21 to control the switching of the conduction state of the two diodes, so that the amplitude and phase of the terahertz transmitted wave emitted by the metal radiating layer 21 are modulated by 1 bit. Here, the transverse central axis refers to the line at the middle position in the transverse direction of the metal receiving layer 21 and parallel to the longitudinal direction of the metal receiving layer.

[0031] Specifically, Figure 2 A detailed schematic diagram of a terahertz transmission wave modulator based on heterogeneous integration of multilayer microstructures is shown. Figure 3 A schematic diagram of a longitudinal cross-section of a terahertz transmission wave modulator based on heterogeneous integration of multilayer microstructures is shown. (See Figure 1) Figure 2 and Figure 3 The metal radiating layer 21 is laid on the upper surface of the substrate material 1, and also includes a first metal radiating patch 9, a second metal radiating patch 10, and a metal square piece 11; the two diodes are a first diode 12 and a second diode 13, respectively. The first metal radiating patch 9 and the second metal radiating patch 10 are symmetrically distributed about the center of the substrate material 1; the metal square piece 11 is located at the center of the substrate material 1; the first diode 12 is located between the first metal radiating patch 9 and the metal square piece 11, and the second diode 13 is located between the second metal radiating patch 10 and the metal square piece 11. The cathode of the first diode 12 is connected to the first metal radiating patch 9, the anode of the first diode 12 is connected to the metal square plate 11, the cathode of the second diode 13 is connected to the metal square plate 11, and the anode of the second diode 13 is connected to the second metal radiating patch 10.

[0032] Specifically, see Figure 2 and Figure 3 The DC trace layer 23 is laid on the lower surface of the insulating material 3, including DC trace 14, matching microstrip line 15 and fan-shaped stub 16; The length of the DC trace 14 is parallel to the longitudinal side length of the insulating material 3. The end of the DC trace 14 is connected to the matching microstrip line 15. A fan-shaped stub 16 with a right angle is connected to each side of the matching microstrip line 15. The matching microstrip line 15 and the fan-shaped stub 16 are used to isolate the DC bias voltage signal from the terahertz transmitted wave.

[0033] Specifically, see Figure 2 and Figure 3 The metal receiving layer 22 is laid on the lower surface of the resin material 4, including a first rectangular metal receiving patch 18 and a second rectangular metal receiving patch 17. The longitudinal lengths of the first rectangular metal receiving patch 18 and the second rectangular metal receiving patch 17 are equal, but the transverse lengths are not equal. The first rectangular metal receiving patch 18 and the second rectangular metal receiving patch 17 are connected by a narrow metal patch 19 to form an H-shaped microstructure.

[0034] Specifically, see Figure 2 and Figure 3 The first metal radiating patch 9 has a first grounding metal blind hole 5 at its center, and the second metal radiating patch 10 has a second grounding metal blind hole 6 at its center. The first grounding metal blind hole 5 and the second grounding metal blind hole 6 penetrate the substrate material 1 and are connected downward to the metal ground layer 2. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration is also provided with a central metal through hole 7, which penetrates the substrate material 1, the metal ground layer 2, the insulating material 3 and the resin material 4, and is connected to the metal square sheet 11 and the metal receiving layer 22 above and below, respectively; a concentric isolation ring 20 is provided in the metal ground layer 2 at the position through which the central metal through hole 7 passes. A DC power supply blind hole 8 is provided on the metal receiving layer 22. The DC power supply blind hole 8 penetrates through the resin material 4 and is connected to the DC trace layer 23 and the metal receiving layer 22 at the top and bottom, respectively. The DC bias voltage signal generated by the DC trace layer 23 is transmitted to the central metal via 7 through the DC power supply blind hole 8, and then reaches the two diodes through the central metal via 7.

[0035] Specifically, see Figure 2 and Figure 3 The DC power supply blind hole 8 is located on the right side of the transverse central axis of the second rectangular metal receiving patch 17, or at the center of the first rectangular metal receiving patch 18.

[0036] Specifically, the central metal through-hole 7 penetrates the second rectangular metal receiving patch 17, and the distance between the center of the central metal through-hole 7 and the left side of the second rectangular metal receiving patch 17 is... x Satisfy: 0 < x ≤265um. Figure 4 The diagram shows the cross-sectional schematics of each metal microstructure layer of a terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration, as well as the annotation of key dimensional parameters. (a) is the cross-sectional schematic of the metal radiating layer and the annotation of key dimensional parameters, (b) is the cross-sectional schematic of the metal ground layer and the annotation of key dimensional parameters, (c) is the cross-sectional schematic of the DC trace layer and the annotation of key dimensional parameters, and (d) is the cross-sectional schematic of the metal receiving layer and the annotation of key dimensional parameters.

[0037] Specifically, the terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration uses no fewer than three types of materials; The substrate material 1 is a semiconductor material or a dielectric material. Semiconductor materials include gallium arsenide, gallium nitride, and silicon, while dielectric materials include quartz and ceramics. Insulating material 3 is a dielectric material with insulating properties, including polycrystalline silicon dioxide; it can adhere well to a variety of substrates (such as quartz, gallium arsenide, and metals).

[0038] Resin material 4 is a high-performance polymer dielectric material, including benzocyclobutene resin, which has good adhesion to various substrates (such as silicon dioxide, quartz, gallium arsenide, and metals).

[0039] The metal ground layer 2, the metal radiation layer 21, the DC trace layer 23, and the metal receiving layer 22 are all made of gold.

[0040] Specifically, the thickness h1 of substrate material 1 satisfies: 50um≤h1≤127um; The thickness h2 of insulating material 3 satisfies: 1um ≤ h2 ≤ 10um; The thickness h3 of resin material 4 satisfies: h3≤20um.

[0041] The thickness t of the metal ground layer 2, the metal radiation layer 21, the DC trace layer 23, and the metal receiving layer 22 satisfies: t≤1um.

[0042] Specifically, see Figure 4 In (a), the side length of the terahertz transmission modulator based on multilayer microstructure heterogeneous integration. p Satisfies: 620um≤ p ≤720um, side length of metal square sheet 11 a Satisfy: 20um≤ a ≤200um; The width of each diode mounting area is [missing information]. b、 The lengths of the first metal radiation patch 9 and the second metal radiation patch 10 are: l 1, width is w 1. Constraints exist: p -(2 w 1+ a +2 b ≥20um, p - l 1≥20um.

[0043] See Figure 4 In (b), the metal ground layer covers the entire substrate material, with a size of p. The diameters of the two grounding metal blind vias and the central metal through-hole are both p. d At the location where the central metal through-hole passes, there exists a concentric isolation ring with a radius of g, where g > 0. d .

[0044] See Figure 4 In (c), the diameter is dThe distance between the power supply blind via (8) and the center metal through-hole (7) is 1. x 1. The DC trace is parallel to the longitudinal side length of the insulating material, and its length is equal to the side length of the insulating material. p Half of the DC trace, the end of the DC trace and the width are s The matching microstrip lines are connected and extend to the pads of the DC-fed blind via. The matching microstrip lines are also connected at a distance from the DC-fed blind via. x Two fan-shaped branches are connected symmetrically at right angles.

[0045] See Figure 4 (d) The metal receiving layer includes layers of equal length. l 2, width is w 2 and w Two rectangular metal patches of size 3 are connected by a space with a width of 3. w Four narrow metal patches are connected to form an "H"-shaped microstructure.

[0046] Specifically, Figure 5 The diagram shows the equivalent connection diagram and the equivalent model schematic diagram of the diodes used in the terahertz transmission wave modulator structure based on multilayer microstructure heterogeneous integration. (a) shows the equivalent connection diagram of the diodes, and (b) shows the equivalent model schematic diagram of the diodes in the on / off state. The two diodes used in the metal radiating layer are of the same type and can operate in the terahertz frequency band (above 100 GHz). Their on / off state is controlled by a DC voltage, and includes, but is not limited to, Schottky switching diodes, Schottky varactor diodes, PIN diodes, or high electron mobility transistors. The two Schottky diodes achieve time-division conduction through the positive or negative voltage provided by the intermediate metal via. Their connection method is as follows: Figure 5 As shown in (a), when a positive voltage Vbias is applied, the right diode is turned on and the left diode is turned off, which is considered State 0; when a negative voltage -Vbias is applied, the left diode is turned on and the right diode is turned off, which is considered State 1. The equivalent lumped circuit model of a single diode is shown in [reference needed]. Figure 5 (b) When the diode is on, it is equivalent to a resistance Ron, and when it is off, it is equivalent to a turn-off capacitance Coff, where Ron does not exceed 5Ω and Coff does not exceed 10fF. For a terahertz incident wave with an electric field direction parallel to the transverse central axis of the metal receiving layer, the positive and negative states of the DC bias voltage can be controlled by digital "01" encoding, which switches the conduction state of the two diodes, thereby changing the equivalent impedance of the modulator's multilayer heterogeneous microstructure, thus changing the amplitude or phase of the incident terahertz wave and allowing it to continue to radiate, achieving amplitude and phase modulation of spatial terahertz.

[0047] The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration disclosed in this application can achieve two modulation effects. The first is phase modulation, where when the two diodes switch their conduction states, the phase difference of the transmitted wave within the effective bandwidth reaches 180 degrees, and the transmission amplitude remains above 80%, achieving 1-bit phase modulation with low transmission loss. The second is amplitude-phase joint modulation, where when the two diodes switch their conduction states, the amplitude of the terahertz transmitted wave within the effective bandwidth switches between below 10% and above 80%, with an amplitude modulation depth exceeding 11 dB, while the phase difference of the transmitted wave exceeds 100 degrees. Therefore, this modulator offers diverse modulation modes and significant technical advantages.

[0048] Example 1 Modulator structure as follows Figure 1 , 2 As shown in Figure 3, the side length of the modulator p =720um, the selected substrate material 1 is quartz (dielectric constant 3.75, loss tangent 0.0004), thickness h 1 = 127 μm; all metallic materials, including metallic layer 2, are gold, with a thickness t = 1 μm; the selected insulating material 3 is silicon dioxide (dielectric constant 3.75, loss tangent 0.0004), with a thickness of t = 1 μm. h 2 = 1µm; the selected resin material 4 is benzocyclobutene resin (dielectric constant 3.75, loss tangent 0.0004), thickness h 3 = 20um.

[0049] like Figure 4 As shown in (a) and (b), the lengths of the first metal radiating patch 9 and the second metal radiating patch 10 of the metal radiating layer 21 are... l 1 = 600um, width is w 1 = 180um, the side length of the metal square sheet 11 a =200um, width of diode mounting area b =50um; the first grounding metal blind hole 5 and the second grounding metal blind hole 6 are located at the exact center of the first metal radiating patch 9 and the second metal radiating patch 10, respectively; the central metal through hole 7 is located at the exact center of the metal square patch 11; the diameter of the three holes is... d =80um, the diameter g of the concentric isolation ring between the central metal through-hole 7 and the metal formation 2 is 100um; like Figure 4 As shown in (c) and (d), the central metal via 7 and the DC power supply blind via 8 are located on the transverse central axis of the second rectangular metal receiving patch 17 of the metal receiving layer 22, and the DC power supply blind via 8 is located to the right of the central metal via 7. x At 1=170um, diameter d1 = 80um. The width of DC trace 14 is 3um, the width of matching microstrip line 15 is 50um, and the distance between the fan-shaped stub 16 and the DC feed blind via 8 is... x 2 = 10µm; the lengths of the second rectangular metal receiving patch 17 and the first rectangular metal receiving patch 18 of the metal receiving layer 22. l 2=650um, the width of the second rectangular metal receiving patch 17 is w2=430um, the width of the first rectangular metal receiving patch 18 is w3=110um, the width of the narrow metal patch 19 is w4=80um, and the distance between the center of the central metal through hole 7 and the left side of the second rectangular metal receiving patch 17 is... x =95um.

[0050] like Figure 5 As shown, the two diodes 12 and 13 are Schottky switching diodes with equivalent circuit parameters Ron=5Ω and Coff=3fF.

[0051] Example 2 Structurally, it's important to note that in this embodiment, the DC feed blind aperture 8 is located at the exact center of the first rectangular metal receiving patch 18 of the metal receiving layer 22, rather than to the right of the second rectangular metal receiving patch 17. Consequently, the metal microstructure of the corresponding DC trace layer 23 is horizontally symmetrical following the position of the DC feed blind aperture 8. The rest of the modulator structure remains as described above. Figure 1 , 2 As shown in Figure 3.

[0052] modulator side length p =620um, the selected substrate material 1 is gallium arsenide (dielectric constant 12.75, loss tangent 0.006), thickness h 1 = 50 μm; all metallic materials, including metallic layer 2, are gold, with a thickness t = 1 μm; the selected insulating material 3 is silicon dioxide (dielectric constant 3.75, loss tangent 0.0004), with a thickness of t = 1 μm. h 2=5um; the selected resin material 4 is benzocyclobutene resin (dielectric constant 3.75, loss tangent 0.0004), thickness h 3 = 20um.

[0053] like Figure 4 As shown in (a) and (b), the lengths of the first metal radiating patch 9 and the second metal radiating patch 10 of the metal radiating layer 21 are... l 1 = 262um, width is w 1 = 140um, the side length of the metal square sheet 11 a =95um, width of diode mounting area b=40um; the first grounding metal blind hole 5 and the second grounding metal blind hole 6 are located at the exact center of the first metal radiating patch 9 and the second metal radiating patch 10, respectively; the central metal through hole 7 is located at the exact center of the metal square piece 11; the diameter of the three holes is... d =70um, the diameter g=140um of the concentric isolation ring between the central metal through hole 7 and the metal formation 2; The relative connection relationships between the central metal through-hole 7 and the second rectangular metal receiving patch 17, the first rectangular metal receiving patch 18, and the narrow metal patch 19 of the metal receiving layer 22 are as follows: Figure 4 As shown in (c) and (d), it should be noted that the DC power supply blind aperture 8 is located at the exact center of the first rectangular metal receiving patch 18 of the metal receiving layer 22, and the aperture diameter is... d = 70um, the corresponding metal microstructure of the DC trace layer 23 is horizontally symmetrical following the position of the DC feed blind via 8, wherein the width of the DC trace 14 is 3um, the width of the matching microstrip line 15 is 35um, and the distance between the fan-shaped stub 16 and the DC feed blind via 8 is... x 2 = 12µm; the lengths of the second rectangular metal receiving patch 17 and the first rectangular metal receiving patch 18 of the metal receiving layer 22. l 2=500um, the width of the second rectangular metal receiving patch 17 is w2=430um, the width of the first rectangular metal receiving patch 18 is w3=80um, the width of the narrow metal patch 19 is w4=50um, and the distance between the center of the central metal through hole 7 and the left side of the second rectangular metal receiving patch 17 is... x =265um.

[0054] like Figure 5 As shown, the two diodes 12 and 13 are Schottky diodes with equivalent circuit parameters Ron=5Ω and Coff=5fF.

[0055] The following simulation experiments, using the three-dimensional full-wave simulation software CST Microwave Studio, are used to simulate the performance of the terahertz transmission wave modulators in Examples 1 and 2 above, to further illustrate the technical effects of this application: Figure 6The diagram shows the transmission amplitude and phase results of Example 1 of a terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration, i.e., a verification diagram of the 1-bit phase modulation effect. (a) represents the transmittance curves of the terahertz wave as a function of frequency in State 0 and State 1 when the two diodes in Example 1 are time-divisionally conducting. It can be seen that Example 1 operates in the 220 GHz band, and the transmittance curves of the two states are basically overlapping, indicating that changing the state does not affect the transmission level. The incident electromagnetic wave has a transmittance exceeding 80% in the 215 GHz-223 GHz band shown in the shaded area of ​​the diagram, indicating that this modulator has good transmission performance within the 8 GHz bandwidth of the 215 GHz-223 GHz terahertz band. Meanwhile, (b) represents the phase curves of the transmitted electromagnetic wave as a function of frequency in State 0 and State 1. It can be seen that the phase curves of the two states are approximately parallel, and the phase difference between the two states is stable at 180 degrees within the effective operating bandwidth shown in the shaded area of ​​the diagram.

[0056] Combination Figure 6 Based on the amplitude (transmittance) and phase results of the terahertz transmitted waves in (a) and (b), at least 80% of the incident terahertz waves are successfully transmitted within the 8 GHz bandwidth of 215 GHz-223 GHz. Furthermore, by switching the conduction states of the two Schottky diodes in a time-division manner using a DC bias voltage, the incident electromagnetic waves can be superimposed with a phase of 0 degrees or 180 degrees before being radiated out again. Compared to existing terahertz modulators with transmittance below 70%, this application, relying on a multilayer microstructure combined with diode dynamic tuning, achieves low transmission loss, fast response speed, and 1-bit phase modulation effect under extremely low-loss transmission of terahertz waves.

[0057] Figure 7The diagram shows the transmission amplitude and phase results of Example 2 of a terahertz transmission wave modulator based on heterogeneous integration of multilayer microstructures, i.e., the verification diagram of the 1-bit amplitude-phase joint modulation effect. (a) represents the terahertz wave transmittance versus frequency curves in State 0 and State 1 when the two diodes in Example 2 are time-divisionally turned on. It can be seen that, compared to State 0, the transmittance curve of the modulator in Example 2 shifts to higher frequencies in State 1. In the 237 GHz band, the transmittance in State 1 is higher than 80%, reaching 84.5% at 237 GHz, indicating successful terahertz wave transmission; while in State 1, the transmittance is lower than 10%, reaching 0.83%, indicating almost no terahertz wave transmission. The transmittance difference between the two states is 76%, meaning the modulation depth reaches 12 dB. Furthermore, within the 234.6 GHz-238.9 GHz band shown in the shaded area of ​​(a), the transmittance difference between the two states exceeds 72%, meaning the modulation depth is greater than 11 dB. This demonstrates that the modulator possesses excellent 1-bit amplitude modulation capability for both transmission and non-transmission of incident electromagnetic waves within the 234.6 GHz-238.9 GHz frequency band. Meanwhile, (b) represents the phase-frequency variation curves of the transmitted electromagnetic wave in State 0 and State 1 of Example 2. It can be seen that within the shaded 234.6 GHz-238.9 GHz frequency band, the phase difference between the two states is 101-133 degrees, greater than 100 degrees. This indicates that it also possesses 1-bit phase modulation capability in both states, and the phase modulation range exceeds 100 degrees.

[0058] Combination Figure 7 Based on the amplitude (transmittance) and phase results of the terahertz transmitted waves in (a) and (b), Example 2 fully verifies that the modulator has the ability to simultaneously control the amplitude and phase of 1 bit in the terahertz band. The amplitude of the terahertz transmitted wave within the effective bandwidth switches between less than 10% and more than 80%, the amplitude modulation depth reaches more than 11dB, and the phase difference of the transmitted wave exceeds 100 degrees.

[0059] In summary, Examples 1 and 2 fully demonstrate that the terahertz transmission wave modulator of this application has diverse control modes and significant technical advantages.

[0060] The above descriptions are merely various embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration, characterized in that, include: The following layers are arranged sequentially from top to bottom: a metal radiating layer (21), a substrate material (1), a metal ground layer (2), an insulating material (3), a DC trace layer (23), a resin material (4), and a metal receiving layer (22); the metal radiating layer (21) includes two diodes. When a terahertz incident wave with an electric field direction parallel to the transverse central axis of the metal receiving layer (22) is incident on the metal receiving layer (22), the DC bias voltage signal generated by the DC trace layer (23) is transmitted to the two diodes of the metal radiating layer (21) to control the switching of the conduction state of the two diodes, so that the amplitude and phase of the terahertz transmitted wave emitted by the metal radiating layer (21) are modulated by 1 bit.

2. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 1, characterized in that, The metal radiation layer (21) is laid on the upper surface of the substrate material (1), and also includes a first metal radiation patch (9), a second metal radiation patch (10), and a metal square piece (11); the two diodes are a first diode (12) and a second diode (13), respectively. The first metal radiating patch (9) and the second metal radiating patch (10) are symmetrically distributed about the center of the substrate material (1); the metal square piece (11) is located at the center of the substrate material (1); the first diode (12) is located between the first metal radiating patch (9) and the metal square piece (11), and the second diode (13) is located between the second metal radiating patch (10) and the metal square piece (11); The cathode of the first diode (12) is connected to the first metal radiating patch (9), the anode of the first diode (12) is connected to the metal square plate (11), the cathode of the second diode (13) is connected to the metal square plate (11), and the anode of the second diode (13) is connected to the second metal radiating patch (10).

3. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 1, characterized in that, The DC trace layer (23) is laid on the lower surface of the insulating material (3) and includes DC traces (14), matching microstrip lines (15) and fan-shaped branches (16). The length direction of the DC trace (14) is parallel to the longitudinal side length of the insulating material (3). The end of the DC trace (14) is connected to the matching microstrip line (15). A fan-shaped stub (16) with a right angle is connected to each side of the matching microstrip line (15). The matching microstrip line (15) and the fan-shaped stub (16) are used to isolate the DC bias voltage signal from the terahertz transmitted wave.

4. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 1, characterized in that, The metal receiving layer (22) is laid on the lower surface of the resin material (4) and includes a first rectangular metal receiving patch (18) and a second rectangular metal receiving patch (17). The first rectangular metal receiving patch (18) and the second rectangular metal receiving patch (17) have the same longitudinal length but different transverse lengths. The first rectangular metal receiving patch (18) and the second rectangular metal receiving patch (17) are connected by a narrow metal patch (19) to form an H-shaped microstructure.

5. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 2, characterized in that, The first metal radiating patch (9) has a first grounding metal blind hole (5) at its center, and the second metal radiating patch (10) has a second grounding metal blind hole (6) at its center. The first grounding metal blind hole (5) and the second grounding metal blind hole (6) penetrate the substrate material (1) and are connected downward to the metal ground layer (2). The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration is further provided with a central metal through hole (7), which penetrates the substrate material (1), the metal ground layer (2), the insulating material (3) and the resin material (4), and is connected to the metal square sheet (11) and the metal receiving layer (22) above and below, respectively; the metal ground layer (2) is provided with a concentric isolation ring (20) at the position through which the central metal through hole (7) passes. A DC-powered blind via (8) is provided on the metal receiving layer (22). The DC-powered blind via (8) penetrates the resin material (4) and is connected to the DC trace layer (23) and the metal receiving layer (22) above and below, respectively. The DC bias voltage signal generated by the DC trace layer (23) is transmitted to the central metal via (7) through the DC-powered blind via (8) and reaches the two diodes through the central metal via (7).

6. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 5, characterized in that, The DC power supply blind hole (8) is located on the right side of the transverse central axis of the second rectangular metal receiving patch (17), or at the center of the first rectangular metal receiving patch (18).

7. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 5, characterized in that, The central metal through-hole (7) penetrates the second rectangular metal receiving patch (17), and the distance between the center of the central metal through-hole (7) and the left side of the second rectangular metal receiving patch (17) is... x Satisfy: 0 < x ≤265um.

8. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 1, characterized in that, Each diode operates in the terahertz frequency band and is a Schottky switching diode, a Schottky varactor diode, a PIN diode, or a high electron mobility transistor.

9. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 1, characterized in that, The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration uses no fewer than three types of materials. The substrate material (1) is a semiconductor material or a dielectric material, wherein the semiconductor material includes gallium arsenide, gallium nitride, and silicon, and the dielectric material includes quartz and ceramic. The insulating material (3) is a dielectric material with insulating properties, and the dielectric material includes polycrystalline silicon dioxide; The resin material (4) is a high-performance polymer medium material, which includes benzocyclobutene resin; The metal ground layer (2), the metal radiation layer (21), the DC wiring layer (23), and the metal receiving layer (22) are all made of gold.

10. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 1, characterized in that, The thickness h1 of the substrate material (1) satisfies: 50um≤h1≤127um; The thickness h2 of the insulating material (3) satisfies: 1um ≤ h2 ≤ 10um; The thickness h3 of the resin material (4) satisfies: h3≤20um. The thickness t of the metal ground layer (2), the metal radiation layer (21), the DC trace layer (23), and the metal receiving layer (22) satisfies: t≤1um.

11. The terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration as described in claim 2, characterized in that, The side length of the terahertz transmission wave modulator based on multilayer microstructure heterogeneous integration p Satisfies: 620um≤ p The side length of the metal square sheet (11) is ≤720um. a Satisfy: 20um≤ a ≤200um; The width of each diode mounting area is [missing information]. b、 The lengths of the first metal radiating patch (9) and the second metal radiating patch (10) are: l 1, width is w 1. Constraints exist: p -(2 w 1+ a +2 b ≥20um, p - l 1≥20um.

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