Terahertz band all-metal micro-nano waveguide

Abstract

The present application relates to a kind of terahertz frequency band full metal micro-nano waveguide, structural system is integrated with full metal structure to realize the integration of structural shape, waveguide channel and positioning hole;Processing technology, flange and waveguide structure are processed respectively by machine tool processing, micro-nano processing;Assembly mode, waveguide and flange are aligned and assembled by pin positioning, at the same time, directly with the waveguide port of micro-nano processing as end face, connect with input / output signal, reduce signal transmission loss.Full metal micro-nano device of the present application has good device reliability and working life compared with metallized silicon-based micro-nano device;Machine tool processing and micro-nano processing are combined to effectively realize the integrated processing of flange and waveguide, improve the surface roughness, sidewall steepness and surface flatness of waveguide structure, reduce radio frequency loss;Alignment assembly and the waveguide port of micro-nano processing as end face, connect with input / output signal, reduce signal transmission loss.

Description

TECHNICAL FIELD

[0001] The present application relates to a full-metal micro-nano waveguide in the terahertz band, belonging to the technical field of micro-nano waveguide structure, which can be applied to micro-nano vacuum electronics, terahertz vacuum tube, terahertz high-power emission source, and slow wave structure manufacturing technology. BACKGROUND

[0002] Terahertz (THz) wave refers to an electromagnetic wave with a wavelength of 3mm-30μm and a frequency of 0.1-10THz, which is between the millimeter wave electrical frequency band and the infrared optical frequency band. Terahertz wave has the advantages of wide frequency band, moderate beam, strong penetration, and high security. In the 6th generation communication technology (6G), terahertz communication technology has become the focus of research in many countries. Due to the strong atmospheric attenuation characteristics of terahertz wave, in order to minimize the electromagnetic loss of terahertz wave in the propagation process, waveguide (WG, Waveguide) as a structure for directional guiding of electromagnetic wave can effectively transmit terahertz signal with low loss. Therefore, waveguide device is an important key core component in the application of terahertz wave.

[0003] With the increase of frequency, the key size of terahertz waveguide device is reduced to micron scale, and the machining and alignment precision of full-metal micro-nano waveguide in the terahertz band is greatly improved compared with that in the microwave band. At present, the machining of microwave band waveguide is realized by machine tool milling process, and the machining precision depends on the size of the tool bit (more than 70μm). The assembly of waveguide and flange is completed by solid glue adhesion, and the surface roughness of the waveguide structure machined by machine tool is usually in the order of tens of microns, while the alignment precision of the device is usually in the order of nearly millimeter, which is difficult to meet the demand of full-metal micro-nano waveguide in the terahertz band, especially for the full-metal micro-nano waveguide device in the terahertz band above 300GHz. There are many studies on the realization of full-metal micro-nano waveguide in the terahertz band by using micro-nano process, such as the silicon-based micro-machined terahertz waveguide studied by Imran Mehdi group in the United States and Joachim Oberhammer group in Sweden, which is an effective means for micro-nano manufacturing of terahertz waveguide. Although this kind of device based on micro-nano process to realize full-metal micro-nano waveguide in the terahertz band has great improvement in working frequency band and transmission performance, the metallization of the device adopts the method of metal plating on the surface of silicon, which is difficult to guarantee the efficiency, reliability and working life of the device. At the same time, the assembly and alignment scheme adopted is to assemble the device first and then connect it with the input / output signal through the flange adapter. Since the adapter is still machined by machine tool, the loss of terahertz wave in the transmission process is large.

[0004] There are also domestic researches in this regard, but relatively insufficient, such as application number 2021109038822 a binocular near-eye display device is given: integrated optical waveguide structure, including: coupling-in component, turning component, coupling-out component, the coupling-in component includes first coupling-in area and second coupling-in area, the first coupling-in area is arranged in the light emitting direction of the first light machine and is used for coupling in the first image light emitted by the first light machine, the second coupling-in area is arranged in the light emitting direction of the second light machine and is used for coupling in the second image light emitted by the second light machine; The turning component includes a first turning region and a second turning region, the first turning region is used for receiving and turning the first image light, and the second turning region is used for receiving and turning the second image light, the coupling-out component includes a first coupling-out area and a second coupling-out area, the first coupling-out area is used for outputting the turned first image light to the left eye of the person, and the second coupling-out area is used for outputting the turned second image light to the right eye of the person, wherein the first turning region, the second turning region, the first coupling-out area and the second coupling-out area are array structures.

[0005] Application number 2021102123913 a real-time online manufacturing detection system of image compression optical chip, ultrafast laser is used for waveguide structure processing of optical chip material according to first control information, for online correction processing of optical chip material according to second control information.

[0006] It is found that the existing technology has the following problems:

[0007] The size of the flange does not match the size of the waveguide. In the terahertz frequency band, the key size of the waveguide is at most a few hundred microns, while the standard flange size of the test system is a few centimeters, that is, the size of the device under test is much smaller than the standard flange interface, which may cause size mismatch between the interface of the existing test equipment and the high-frequency terahertz device, and it is also difficult to realize the preparation of micron-nanometer level size devices, and currently most of them are metalized silicon-based micro-nano devices. The difference in size leads to different processing methods. The flange in the present application is suitable for milling with a precision machine tool, but the precision machine tool cannot meet the precision and roughness of the waveguide structure; micro-nano processing can prepare micro-nano precision structures such as waveguides with high precision, but it cannot make flanges such large-size, relatively mechanically strong and bulky metal structures, which makes it impossible to use the same processing method to process the flange and the waveguide on the same material at one time, thereby affecting the service life and reliability of the device.

[0008] Alignment and positioning error during assembly. High-frequency waveguide devices need to use distributed parameters to analyze signals in the terahertz frequency band with wavelengths in the millimeter or even micron scale, and the assembly accuracy of the connection of waveguide components in the waveguide transmission line is a key factor affecting the performance of the waveguide components and the transmission power loss of the transmission line. The connection of the waveguide components will directly affect the coincidence of the waveguide ports. In the existing scheme, the straight waveguide and the flange are bonded by adhesive, and the bonding of the adhesive is often accompanied by problems such as misalignment, overflow of adhesive, gaps caused by insufficient adhesive, and decreased firmness caused by aging of the adhesive over time. Therefore, positioning errors occur during the assembly process, which further affects the assembly accuracy of the connection of the waveguide components.

[0009] The waveguide port is machined by a machine tool. Due to the limitations of equipment technology, the existing traditional waveguide has deficiencies in process accuracy, surface roughness, and side wall steepness, which further causes transmission loss and an undesirable dispersion relationship, affecting the overall performance of the waveguide. SUMMARY

[0010] The present application provides a kind of terahertz frequency band full metal micro-nano waveguide, it is improved to traditional waveguide from three aspects of structure system, processing technology and assembly mode to be suitable for the processing accuracy and assembly alignment requirement of terahertz frequency band.

[0011] To achieve the above object, the present application provides the following technical scheme: a kind of terahertz frequency band full metal micro-nano waveguide, structure system is integrated with the positioning hole of waveguide channel and the structure shape of full metal structure;

[0012] Processing technology, flange and waveguide structure are machined by machine tool machining and micro-nano machining respectively;

[0013] Assembly mode, waveguide structure and flange are aligned and assembled by pin positioning, and the waveguide port machined by micro-nano machining is directly used as the end face connected with input / output signal, reducing signal transmission loss.

[0014] Further, the full metal refers to a metal material with good heat dissipation and electrical conductivity and high hardness.

[0015] Further, the metal material is one of copper, gold, silver and aluminum.

[0016] Further, the structure system includes a flange, the flange is composed of an upper half flange and a lower half flange, flange assembly screw holes are arranged on the upper half flange and the lower half flange, and the flange is fixed by assembly screws, waveguide grooves are arranged on opposite surfaces of the upper half flange and the lower half flange, the waveguide is arranged in the waveguide groove, pin positioning holes and screw positioning holes are arranged on the waveguide, and pin positioning holes and screw positioning holes are correspondingly arranged on the flange for positioning connection.

[0017] Further, the waveguide is a flat waveguide, including an upper half waveguide and a lower half waveguide provided with a groove waveguide port, or other waveguide structures provided at different positions and numbers of openings, wherein the upper half waveguide and the lower half waveguide are both provided with symmetrically distributed pin positioning holes and screw positioning holes.

[0018] Further, the upper half waveguide and the lower half waveguide are each provided with four pin positioning holes, two in a group and symmetrically arranged, and one screw positioning hole on each side of each group of pin positioning holes.

[0019] Further, the upper half flange and the lower half flange are both in the shape of an I-shaped section, and the flange plates of the upper half flange and the lower half flange are both semicircular.

[0020] Further, the machine tool processing refers to milling a standard flange plate and a connecting pin hole on a complete metal block by a precision machine tool, including an upper half flange and a lower half flange, and a test screw interface, two test pin interfaces, and two flange assembly half screw holes at the edges on the upper half flange and the lower half flange, respectively.

[0021] Further, the micro-nano processing refers to processing a waveguide structure by photolithography and etching.

[0022] Further, a silicon-based substrate is used as a device sacrificial layer, a waveguide structure pattern is formed on the silicon-based substrate layer by a photolithography and etching patterning process, and a terahertz frequency full-metal waveguide structure is formed by a metal deposition, demolding and bonding process.

[0023] Compared with the prior art, the present application has the following advantages:

[0024] 1. In terms of structural system, the terahertz waveguide proposed in the present application is a full-metal micro-nano device, which has good device reliability and working life compared with a metalized silicon-based micro-nano device.

[0025] 2. In terms of processing technology, the terahertz waveguide process adopts a hybrid method of machine tool processing and micro-nano processing, which can effectively realize integrated processing and assembly of the flange and the waveguide, and the introduction of the micro-nano processing technology improves the surface roughness, sidewall steepness and surface flatness of the waveguide structure, and reduces the radio frequency loss.

[0026] 3. In terms of assembly method, the waveguide structure and the flange are aligned and assembled by pin positioning, and the waveguide port processed by micro-nano processing is directly used as an end face to connect with the input / output signal, thereby reducing the signal transmission loss. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The figure is a structural front view of the present application.

[0028] Figure 2 is a top view of the upper half flange structure of the present application;

[0029] Figure 3 is a top view of the lower half flange structure of the present application.

[0030] In the figure: 1, upper half flange, 2, lower half flange, 3, test screw interface, 4, test pin interface, 5, half screw hole, 6, waveguide, 7, pin positioning hole, 8, screw positioning hole. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0032] Embodiment 1

[0033] As shown in Fig. 1, a full-metal micro-nano waveguide in the terahertz band is provided, which is a full-metal structure and integrates the structure shape, waveguide channel and positioning hole. Figure 1 , 2 The full-metal refers to a metal material with good heat dissipation and conductivity and high hardness. The metal material can be one of copper, gold, silver and aluminum.

[0034] For the flange structure in this example, a precision machine tool is used to mill a standard flange and a connecting pin hole on a complete metal block, and the flange is divided into an upper half flange 1 and a lower half flange 2, and a test screw interface 3, two test pin interfaces 4 and two flange assembly half screw holes 5 at the edge are respectively processed on the upper half flange 1 and the lower half flange 2.

[0035] The connecting surfaces of the upper half flange 1 and the lower half flange 2 are both I-shaped, and the flange plates of the upper half flange 1 and the lower half flange 2 are both semicircular. Flange assembly screw holes are arranged on the upper half flange 1 and the lower half flange 2, and are fixed into a flange through assembly screws. Waveguide grooves are arranged on the opposite surfaces of the upper half flange 1 and the lower half flange 2, and a waveguide 6 is arranged in the waveguide grooves. Pin positioning holes 7 and screw positioning holes 8 are arranged on the waveguide 6, and corresponding pin positioning holes 7 and screw positioning holes 8 are arranged on the flange for positioning connection.

[0036] For the waveguide 6 in the example, the upper half waveguide and the lower half waveguide each have four pin positioning holes in the middle, two in a group symmetrically arranged, and one screw positioning hole on each side of each group of pin positioning holes. By using micro-nano processing technology, based on silicon-based materials, using photolithography for structure patterning, etching the silicon substrate to form a mold, metal deposition to fill the silicon mold, wet etching to release the silicon structure, metal bonding to form a complete waveguide cavity, and other micro-nano manufacturing technologies, a high-precision, high-performance, and miniaturized terahertz high-frequency high-power all-metal waveguide structure is realized.

[0037] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A terahertz band all-metallic micro-nano waveguide, characterized in that: The structure system is integrated by a full metal structure to realize the integration of the structure shape, the waveguide channel and the positioning hole; the flange and the waveguide structure are machined by machine tool machining and micro-nano machining respectively; the waveguide and the flange are aligned and assembled by pin positioning, and the micro-nano processed waveguide port is directly used as an end face to connect with the input / output signal, thereby reducing the signal transmission loss; the structure system comprises a flange, the flange is composed of an upper half flange and a lower half flange, flange assembly screw holes are arranged on the upper half flange and the lower half flange, the flange is fixed by assembly screws, waveguide grooves are arranged on the opposite surfaces of the upper half flange and the lower half flange, the waveguide is arranged in the waveguide groove, pin positioning holes and screw positioning holes are arranged on the waveguide, and corresponding pin positioning holes and screw positioning holes are arranged on the flange for positioning connection.

2. The THz-band all-metallic micro-nano waveguide according to claim 1, wherein: The full metal refers to a metal material with good heat dissipation and conductivity and high hardness.

3. The THz-band all-metallic micro-nano waveguide according to claim 2, wherein: The metal material is one of copper, gold, silver and aluminum.

4. The THz-band all-metallic micro-nano waveguide according to claim 1, wherein: The waveguide is a flat waveguide, comprising an upper half waveguide and a lower half waveguide, a recess waveguide port is arranged on the upper half waveguide and / or the lower half waveguide, and pin positioning holes and screw positioning holes are arranged on the upper half waveguide and the lower half waveguide.

5. The all-metallic micro-nano waveguide operating in THz regime according to claim 4, wherein: An even number of pin positioning holes are arranged in the middle of the upper half waveguide and the lower half waveguide, and two pin positioning holes are symmetrically arranged in a group, and one screw positioning hole is arranged on each side of the pin positioning hole group. 6.The THz-band all-metallic micro-nano waveguide according to claim 1, wherein: The connecting surfaces of the upper half flange and the lower half flange are both I-shaped, and the flange plates of the upper half flange and the lower half flange are both semicircular. 7.The THz-band all-metallic micro-nano waveguide according to claim 1, wherein: The machine tool machining refers to milling a standard flange plate and a connecting pin hole on a complete metal block by a precision machine tool, comprising an upper half flange and a lower half flange, and a test screw interface, two test pin interfaces and two flange assembly half screw holes at the edge on the upper half flange and the lower half flange respectively. 8.The THz-band all-metallic micro-nano waveguide according to claim 1, wherein: The micro-nano machining refers to machining a waveguide structure by at least a photoetching and etching process. 9.The THz-band all-metallic micro-nano waveguide according to claim 8, wherein: A silicon substrate is used as a device sacrificial layer, a waveguide structure pattern is formed on the silicon substrate layer by a photoetching and etching patterning process, a terahertz frequency full metal waveguide structure is formed by a metal deposition, demolding and bonding process.

Images