Double-sided radiation device of composite right / left-handed metamaterial waveguide with double-channel structure

Abstract

The invention discloses a double-sided radiation device of a composite right / left-handed metamaterial waveguide with a double-channel structure, which comprises a plurality of waveguide units, an input waveguide and a tunneling waveguide, and is characterized in that the plurality of periodically repeated waveguide units are arranged to form a metamaterial array; the input waveguide is connected to one end of the metamaterial array and is used for feeding in electromagnetic waves; the tunneling waveguide is arranged between the input waveguide and the metamaterial array; wherein the waveguide unit comprises a first resonant cavity, a second resonant cavity, an upper channel and a lower channel, the upper channel and the lower channel are arranged between the first resonant cavity and the second resonant cavity, and the upper channel and the lower channel are used for transmitting electromagnetic waves on the upper surface and the lower surface of the metamaterial array respectively. The method can be applied to the fields of double-sided plasma chemical vapor deposition and the like, the space utilization rate and the production efficiency of equipment can be multiplied, and the method has remarkable technical advantages and wide application prospects.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of plasma deposition, and relates to a double-face radiation device of a composite left-right hand metamaterial waveguide with a double-channel structure. BACKGROUND

[0002] Microwave plasma chemical vapor deposition (MPCVD) technology has become the mainstream technology for preparing high-purity and high-quality diamond films due to its characteristics of no electrode pollution and high-density plasma. However, the traditional MPCVD equipment still faces challenges in practical application. On the one hand, the energy distribution and spatial form of the plasma of the conventional resonant cavity type MPCVD system are strictly limited by the inherent resonant mode of the cavity, which leads to uneven energy distribution when growing large-size diamond, thereby introducing lattice defects in the edge region of the wafer and affecting product quality and yield.

[0003] In order to break through the limitation of the resonant mode, researchers have developed a plasma source based on surface waves. In particular, the use of composite right and left hand (CRLH) metamaterial waveguide to excite surface wave plasma shows great potential. CRLH metamaterial is an artificial electromagnetic structure, and its unique dispersion characteristics can realize precise control of electromagnetic wave phase. When working in the zero-order resonant state, the CRLH waveguide can form a phase-constant surface current on its surface, i.e. realize infinite wavelength propagation. By slotting at the position where the surface current is concentrated, electromagnetic waves of the same phase can be efficiently radiated outward, thereby exciting large-area, high-density and high-uniformity surface wave plasma on the dielectric plate, effectively solving the problems of low energy utilization rate and non-uniform plasma of traditional MPCVD equipment.

[0004] However, the existing CRLH metamaterial waveguide device still has obvious limitations in structural design. These devices are usually single-channel and single-face radiation structures, i.e. only one surface of the waveguide is used for slotting and energy radiation. For the entire waveguide structure, the space on the other side is not utilized, resulting in waste of space resources and limiting the further improvement of production efficiency. If double-face radiation can be achieved, it means that double production tasks (such as double-face film deposition) can be carried out simultaneously on the basis of a set of waveguide system, which will greatly improve the space utilization rate and production efficiency of the equipment.

[0005] However, it is a severe technical challenge to feed two output channels evenly and stably from a single input port in microwave engineering. Simple power distribution structures (such as T-junctions) often cannot guarantee that the power and phase of the two channels are completely consistent, and can easily cause unnecessary electromagnetic oscillation in one of the channels, leading to imbalance of the entire system and failure to form a stable in-phase surface current. Therefore, how to design a metamaterial waveguide structure that can be stably driven from a single input source and achieve uniform and in-phase radiation on both sides is a technical problem that needs to be solved in the field. SUMMARY

[0006] To solve the defects in the prior art, the present application provides a double-channel structure composite left-right hand metamaterial waveguide double-sided radiation device, and the technical scheme is as follows: The device comprises a plurality of waveguide units, an input waveguide and a tunneling waveguide, wherein, The waveguide units are arranged in a periodic array to form a metamaterial array; the input waveguide is connected to one end of the metamaterial array and used for feeding electromagnetic waves; and the tunneling waveguide is arranged between the input waveguide and the metamaterial array. The waveguide unit comprises a first resonant cavity, a second resonant cavity and an upper channel and a lower channel arranged between the first resonant cavity and the second resonant cavity, and the upper channel and the lower channel are used for transmitting electromagnetic waves on the upper surface and the lower surface of the metamaterial array, respectively.

[0007] Preferably, the width of the tunneling waveguide is set such that the fed electromagnetic waves are in a cutoff state at the width, so as to couple energy from the input waveguide to the upper channel and the lower channel of the metamaterial array through the waveguide tunneling effect, thereby generating double-sided in-phase surface current radiation on the upper and lower surfaces of the metamaterial array.

[0008] Preferably, the second resonant cavity of a previous waveguide unit and the first resonant cavity of a subsequent waveguide unit in the periodically repeated waveguide units in the metamaterial array are shared.

[0009] Preferably, the frequency of the electromagnetic waves fed by the input waveguide is 2.45 GHz.

[0010] Preferably, the width of the tunneling waveguide is consistent with the width of the upper channel.

[0011] Preferably, the width of the tunneling waveguide is 59±4 mm, and the length is 28-36 mm.

[0012] Preferably, the waveguide unit has a composite left-right hand characteristic, and the phase difference between the input and the output is zero at a preset working frequency.

[0013] Compared with the prior art, the present application at least has the following beneficial effects: 1. Compared with the common composite left and right hand metamaterial waveguide structure, the metamaterial waveguide radiates electromagnetic waves by adopting a double-channel double-surface structure, and the space utilization of the entire metamaterial waveguide device is doubled.

[0014] 2. The device is composed of multiple repeated units, a tunnel waveguide and a rectangular input waveguide, the unit structure adopts two channels for transmission and radiation of microwaves, one unit is taken as a period, two channels share one resonant cavity to generate in-phase surface current, and the surfaces of the two channels can radiate electromagnetic waves in two directions to deposit diamond film.

[0015] 3. The device can effectively improve the production efficiency of diamond film deposition, and through less space occupation and higher waveguide utilization, the device realizes the maximization of production benefit and deposition efficiency by depositing diamond on two surfaces. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a structure schematic diagram of a double-channel structure composite left and right hand metamaterial waveguide double-surface radiation device of an embodiment of the present application; Figure 2 It is a three-dimensional structure schematic diagram of a waveguide unit of a double-channel structure composite left and right hand metamaterial waveguide double-surface radiation device of an embodiment of the present application; Figure 3 It is a three-layer split structure schematic diagram of a waveguide unit of a double-channel structure composite left and right hand metamaterial waveguide double-surface radiation device of an embodiment of the present application; Figure 4 It is a three-view structure diagram of a waveguide unit of a double-channel structure composite left and right hand metamaterial waveguide double-surface radiation device of an embodiment of the present application; Figure 5 It is a physical structure diagram of a waveguide unit of a double-channel structure composite left and right hand metamaterial waveguide double-surface radiation device of an embodiment of the present application; Figure 6 It is a dispersion curve of a waveguide unit of a double-channel structure composite left and right hand metamaterial waveguide double-surface radiation device of an embodiment of the present application; Figure 7 It is a surface current intensity diagram of an upper channel and a lower channel of a metamaterial array of a double-channel structure composite left and right hand metamaterial waveguide double-surface radiation device of an embodiment of the present application; Figure 8 It is a surface current vector diagram of an upper channel and a lower channel of a metamaterial array of a double-channel structure composite left and right hand metamaterial waveguide double-surface radiation device of an embodiment of the present application; Figure 9 It is a surface current intensity diagram of all surfaces of a metamaterial array of a double-channel structure composite left and right hand metamaterial waveguide double-surface radiation device of an embodiment of the present application; Figure 10Surface current intensity map of the tunneling waveguide of the metamaterial array of the double-sided radiation device of the dual-channel structure composite left-right hand metamaterial waveguide of the embodiment of the present application; Figure 11 Surface current intensity map of the metamaterial array of the double-sided radiation device of the dual-channel structure composite left-right hand metamaterial waveguide of the embodiment of the present application in unbalanced state. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0018] On the contrary, the present application covers any substitution, modification, equivalent method and scheme made by the claims within the essence and scope of the present application. Further, in order to make the public have a better understanding of the present application, some specific details are described in detail in the following detailed description of the present application. The present application can also be completely understood without the description of these details by those skilled in the art.

[0019] Referring to Figure 1 , a double-sided radiation device of a dual-channel structure composite left-right hand metamaterial waveguide of an embodiment of the present application is shown, comprising a plurality of waveguide units 10, an input waveguide 20 and a tunneling waveguide 30, wherein, The plurality of periodically repeated waveguide units 10 are arranged to form a metamaterial array; the input waveguide 20 is connected to one end of the metamaterial array for feeding electromagnetic waves; the tunneling waveguide 30 is arranged between the input waveguide 20 and the metamaterial array. The waveguide unit 10 comprises a first resonant cavity 11, a second resonant cavity 12 and an upper channel 13 and a lower channel 14 arranged between the first resonant cavity 11 and the second resonant cavity 12, the upper channel 13 and the lower channel 14 being used for transmitting electromagnetic waves on the upper surface and the lower surface of the metamaterial array, respectively.

[0020] The width of the tunneling waveguide 30 is arranged to be such that the fed electromagnetic waves are in a cutoff state at the width, so as to couple energy from the input waveguide 20 to the upper channel 13 and the lower channel 14 of the metamaterial array through the waveguide tunneling effect, thereby generating double-sided in-phase surface current radiation on the upper and lower surfaces of the metamaterial array.

[0021] In the periodically repeated waveguide units 10 in the metamaterial array, the second resonant cavity 12 of a previous waveguide unit 10 is shared with the first resonant cavity 11 of a subsequent waveguide unit 10. The electromagnetic wave frequency fed by the input waveguide 20 is 2.45 GHz. The width of the tunneling waveguide 30 is consistent with the width of the upper channel 13.

[0022] In a specific embodiment, the tunneling waveguide 30 has a width of 59±4 mm and a length of 28-36 mm. The waveguide unit 10 has composite left- and right-handed characteristics, and its dispersion curve has zero phase difference between the input and output at a preset operating frequency.

[0023] The overall design process of the device is as follows: First, a single 10-element metamaterial waveguide structure was designed. Existing composite left- and right-handed metamaterial waveguides used for diamond thin film deposition are single-channel structures, with each unit consisting of a channel and a resonant cavity. Based on this structure, a dual-channel structure was designed (see [reference needed]). Figure 2 In a waveguide unit 10 structure, there are three layers. The first and third layers are rectangular resonant cavities of the same size. The first resonant cavity 11 is used to receive the electromagnetic waves transmitted from the previous waveguide unit 10 and adjust the phase. The middle layer connects the first resonant cavity 11 and the second resonant cavity 12 of the third layer. Energy transmission between the upper channel 13 and the lower channel 14 is achieved through rectangular blocks of the same size. The second resonant cavity 12 of the third layer completes secondary phase adjustment and transmits energy to the subsequent waveguide unit 10. Dimensional parameters (X0=6±0.3mm, Y0=86.36±0.2mm, Z0=73±5mm, X1=12±0.5mm, Y1=59±4mm, Z1=28±5mm). Figure 3 This corresponds to the three-layer split diagram of the waveguide unit 10 structure. Figure 4 The corresponding view is the three-view diagram of the waveguide unit 10 structure. In this waveguide unit 10 structure, the modeled area represents the morphology of the internal air cavity of the metamaterial waveguide; that is, the modeled part is not a solid metal structure. In actual production, the solid structure of the dual-channel metamaterial waveguide unit 10 is... Figure 5 .

[0024] Secondly, dispersion curve analysis was performed on the dual-channel unit structure, see [link to relevant documentation]. Figure 6 The dispersion curve proves that the unit cell structure possesses composite left- and right-handed characteristics. Above 2.45 GHz, the image conforms to a right-handed propagation curve; below 2.45 GHz, the image conforms to a left-handed propagation curve. At 2.45 GHz, the input-output phase difference of the unit cell structure is zero, meaning that the input and output currents are in phase in this unit cell structure, at which point the electromagnetic wave propagates with an infinite wavelength. According to... Figure 6 The simulation results show that the measured 3MHz bandgap is better than the industrial 10MHz tolerance standard, ensuring equipment stability. Regarding this dispersion curve, Figure 2 The dimensional parameters of the unit structure for propagation at an infinite wavelength of 2.45 GHz are provided. Under these dimensional parameters, the unit structure can achieve in-phase current propagation with extremely low error.

[0025] Next, these composite left- and right-handed units are repeatedly arranged into a metamaterial array, see [link to previous section]. Figure 1 The resonant cavities of the front and rear waveguide units 10 are connected in pairs, and then an input waveguide 20 and a tunneling waveguide 30 are connected to form a composite left- and right-handed metamaterial waveguide array. The rectangular waveguide serves as the input waveguide 20, and the tunneling waveguide 30 connects the input to the repeating unit array to maintain the electromagnetic stability of the structure. Each repeating unit has two channels, one above and one below, so the array also has two channels. Figure 1 101 is the lower channel of the array. There are a large number of surface currents on the surface of the channel. The propagation image of the surface currents in phase will be shown later.

[0026] Finally, a 2.45 GHz electromagnetic wave is input to the rectangular waveguide input terminal. The electromagnetic wave passes through the tunneling waveguide 30, simultaneously generating in-phase surface currents in the upper channel 13 and lower channel 14 of the array. (See [reference]). Figure 7 The array forms a surface current with a significant central intensity on the surfaces of the upper channel 13 and the lower channel 14, and the surface current intensity does not change with the propagation distance along the current propagation direction. Figure 8 In the image, we can see the vector propagation image of the surface current of the entire array structure. We can find that the vector direction of the surface current is exactly the same along the current propagation direction, which indicates that the surface current is in phase. Figure 9 It is a surface current intensity diagram of all surfaces of the entire array structure.

[0027] It is worth noting the surface current propagation image of tunnel waveguide 30, see [link / reference]. Figure 10 The tunneling waveguide 30 has a width of 59±4 mm. At this width, 2.45 GHz electromagnetic waves are cut off and cannot propagate normally. However, by connecting one end to the input waveguide 20 and the other end to the metamaterial waveguide unit 10, waveguide tunneling is formed. The energy of the input waveguide 20 is transmitted to the metamaterial waveguide stably with very low energy loss through the waveguide tunneling. This stable transmission will suppress electromagnetic oscillations and instabilities in the dual-channel structure. The length of the tunneling waveguide 30 is conditionally limited along the electromagnetic wave propagation direction. Tests have shown that, under the specified dimensional parameters of this design, the length can be selected in the range of 28 mm to 36 mm (when the structural dimensions change, this range needs to be scanned to determine the optimal value). Among them, the in-phase surface current generated through the 31 mm tunneling waveguide 30 is the most ideal, achieving the best state in terms of stability, uniformity, and strength. If the length of the tunneling waveguide 30 is chosen to be too long or too short, outside the aforementioned range, the electromagnetic wave will generate unstable electromagnetic oscillations on both the upper and lower surfaces of the array. The output will no longer be a surface current in phase, but rather an unbalanced surface current. See [link to relevant documentation]. Figure 11 The width of the tunnel waveguide 30 must be equal to the width of the channel (Y1=59±4mm).

[0028] The technical effects achieved by the present invention through the above settings include: 1. Doubled Space Utilization and Production Efficiency: The innovative dual-channel unit structure design enables bi-lateral radiation on the same device, directly doubling space utilization. In applications such as MPCVD, simultaneous deposition on both sides can be achieved, resulting in a significant improvement in production efficiency.

[0029] 2. Stable and uniform energy distribution: The innovative introduction of a tunneling waveguide as a coupling structure cleverly solves the problem of stable and uniform energy distribution from single input to dual output, effectively suppressing electromagnetic oscillations and ensuring the reliability and consistency of double-sided radiation.

[0030] 3. High energy utilization: Inheriting the advantages of CRLH metamaterial zero-order resonance, it can generate high-intensity in-phase surface currents on both the upper and lower surfaces and radiate energy outwards efficiently, resulting in high energy utilization.

[0031] 4. Broad application prospects: The double-sided radiation device of the present invention opens up new possibilities for microwave plasma applications, such as building a dual-cavity MPCVD system, or being applied in other fields that require a double-sided, large-area, uniform energy field.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A bifacial radiating device based on a dual-channel composite left- and right-handed metamaterial waveguide, characterized in that, It includes several waveguide units, an input waveguide, and a tunneling waveguide, among which, A metamaterial array is formed by arranging multiple periodically repeating waveguide units; an input waveguide is connected to one end of the metamaterial array for feeding electromagnetic waves; a tunneling waveguide is disposed between the input waveguide and the metamaterial array. The waveguide unit includes a first resonant cavity, a second resonant cavity, and an upper channel and a lower channel disposed between the first resonant cavity and the second resonant cavity. The upper channel and the lower channel are used to transmit electromagnetic waves on the upper and lower surfaces of the metamaterial array, respectively.

2. The bifacial radiation device of the dual-channel composite left- and right-handed metamaterial waveguide according to claim 1, characterized in that, The width of the tunneling waveguide is set such that the fed electromagnetic wave is cut off at this width, so that energy is coupled from the input waveguide to the upper and lower channels of the metamaterial array through the waveguide tunneling effect, thereby generating bifacial in-phase surface current radiation on the upper and lower surfaces of the metamaterial array.

3. The bifacial radiating device of the dual-channel composite left- and right-handed metamaterial waveguide according to claim 1, characterized in that, In the periodically repeating waveguide units of the metamaterial array, the second resonant cavity of the previous waveguide unit is shared with the first resonant cavity of the next waveguide unit.

4. The bifacial radiating device of the dual-channel composite left- and right-handed metamaterial waveguide according to claim 1, characterized in that, The electromagnetic wave fed into the input waveguide has a frequency of 2.45 GHz.

5. The bifacial radiating device of the dual-channel composite left- and right-handed metamaterial waveguide according to claim 1, characterized in that, The width of the tunneling waveguide is the same as the width of the upper channel.

6. The bifacial radiating device of the dual-channel composite left- and right-handed metamaterial waveguide according to claim 1, characterized in that, The tunneling waveguide has a width of 59±4 mm and a length of 28-36 mm.

7. The bifacial radiating device of the dual-channel composite left- and right-handed metamaterial waveguide according to claim 1, characterized in that, The waveguide unit has composite left-handed and right-handed characteristics, and its dispersion curve has zero phase difference between input and output at the preset operating frequency.

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