High-precision alignment assembly method, alignment mark and application based on micro-nano process

Abstract

The present invention provides a high-precision alignment assembly method, alignment mark and application based on micro-nano technology. After preparing an electron gun, a corresponding alignment mark is formed on the electron gun; a slow-wave structure prepares a corresponding alignment mark; the alignment mark of the slow-wave structure is aligned with the alignment mark of the electron gun to achieve alignment molding. The present invention converts the alignment of two waveguide structure ports into the alignment of planar alignment symbols by using alignment symbols commonly used in micro-nano technology, thereby achieving precise assembly of high-frequency, micro-sized structural devices and greatly improving the accuracy of alignment assembly. The assembly requirements of miniaturized and integrated traveling wave tubes can be achieved, and the utilization efficiency of signals can be effectively improved, signal loss can be reduced, and overall gain and output power can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of high-precision assembly, and in particular to a high-precision alignment assembly method, alignment mark and application based on micro-nano technology. Background Art

[0002] Since the birth of the first traveling wave tube in the middle of the last century, the performance of traveling wave tubes has been in constant development, pursuing characteristics such as high power, high frequency, wide bandwidth and small size. The requirements for its production and manufacturing process are becoming more and more stringent, but the technology in its production and assembly process is relatively backward. In the assembly process of traveling wave tube parts, the development cycle is long, the process is cumbersome, and the yield rate is low. Therefore, better means must be used to improve the production efficiency of traveling wave tubes and increase the yield rate.

[0003] In the design of traveling wave tubes in lower frequency bands, due to the large critical dimensions, the design and manufacture of traveling wave tubes are mainly completed by manual operation. The existing traveling wave tube assembly method often adopts digital mechanical processing methods. For example, the existing milling processing technology adopts the pin hole alignment method in the assembly process of the traveling wave tube. The pin connection method is as follows Figure 1 As shown in the figure, this method can effectively improve the manufacturing efficiency and quality of the traveling wave tube. However, when the operating frequency of the traveling wave tube rises to the terahertz frequency band, the size of the high-frequency terahertz device is greatly reduced, and the alignment error of the pin hole connection method can only be maintained at the order of tens of microns or several microns, which cannot meet the needs of traveling wave tube manufacturing. Therefore, limited by the accuracy of processing equipment and assembly equipment, there is a large error in the assembly accuracy of the traveling wave tube.

[0004] The existing processing schemes of the traveling wave tube slow-wave structure and the electron gun can be realized by using micro-nano processing technology. Therefore, in combination with the existing micro-nano processing technology, a high-precision alignment and assembly scheme based on micro-nano processing technology is proposed. By using photolithography and overlay alignment technology, the alignment of the electron gun structure and the slow-wave structure is realized on the same alignment layer substrate. Summary of the invention

[0005] The purpose of the present invention is to provide a high-precision alignment and assembly method, alignment mark and application based on micro-nano technology, which adopts the overlay alignment technology of micro-nano processing to greatly improve the assembly accuracy of micro-nano devices.

[0006] According to one object of the present invention, the present invention provides a high-precision alignment and assembly method based on micro-nano technology, comprising the following steps:

[0007] S1, after preparing the electron gun, forming a corresponding alignment mark on the electron gun;

[0008] S2, slow-wave structure preparation corresponding alignment marks;

[0009] S3, aligning the alignment mark of the slow-wave structure with the alignment mark of the electron gun to achieve alignment molding.

[0010] Furthermore, in S1 and S2, while preparing the corresponding electron gun and slow-wave structure, an alignment mark is prepared. At the same time, the alignment mark is positioned and prepared on the alignment layer substrate according to the designed size parameters, and its size positioning is the same as that of the micro-nano structure and the slow-wave structure.

[0011] Furthermore, the alignment of the alignment marks is achieved using micro-nano equipment such as photolithography equipment, bonding equipment, etc., which can achieve high-precision structural alignment.

[0012] Furthermore, when the structure is opaque, an alignment symbol is prepared on the back of the structure, an alignment mark is prepared on the alignment layer substrate, and the alignment of the metal structure is achieved through a microscope.

[0013] Furthermore, alignment marks are marked on the prepared electron gun and slow-wave structure at the same time, and alignment marks are prepared on the alignment layer substrate at the same time. After the three are aligned in the microelectronic equipment of the lithography machine, the structures are assembled by bonding to achieve the alignment and assembly of the high-precision traveling wave tube.

[0014] Furthermore, the assembly means also include bonding and high-precision pin hole micro-nano process assembly methods.

[0015] Furthermore, the alignment mark includes alignment mark alignment, off-axis alignment, on-axis alignment, laser scanning video image alignment or grating alignment, etc.

[0016] According to another object of the present invention, the present invention provides an alignment mark for high-precision alignment assembly based on micro-nano technology, including an alignment layer substrate and an electron gun alignment mark arranged on the alignment layer substrate and a slow-wave structure mark arranged on the alignment layer substrate, the electron gun alignment mark and the slow-wave structure mark being arranged correspondingly.

[0017] According to the third object of the present invention, the present invention provides an application of a high-precision alignment and assembly method based on micro-nano technology, which is applied to the alignment and assembly of microstructure devices with high frequency, micro size and high process precision requirements.

[0018] Furthermore, the invention is also applied to the alignment and assembly of slow-wave structures, magnetic focusing systems and collector components, or high-frequency waveguide devices and high-frequency passive devices.

[0019] The technical solution of the present invention converts the alignment of two waveguide structure ports into the alignment of plane alignment symbols by using alignment symbols commonly used in micro-nano technology, realizes the precise assembly of high-frequency, micro-sized structural devices, and greatly improves the accuracy of alignment and assembly. It can realize the assembly requirements of miniaturized and integrated traveling wave tubes, effectively improve the utilization efficiency of signals, reduce signal loss, and improve overall gain and output power. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a schematic diagram of a pin connection method in the prior art of the present invention;

[0022] Figure 2 It is a plan view schematic diagram of a terahertz traveling wave tube electron gun and a slow wave structure according to an embodiment of the present invention;

[0023] Figure 3 A schematic diagram of the structure of an alignment mark in an embodiment of the present invention;

[0024] Figure 4 A schematic diagram of a structure in which structural alignment is achieved by aligning marks using a one-step alignment method in an embodiment of the present invention;

[0025] Figure 5 A schematic diagram of a structure in which structural alignment is achieved by aligning marks using a two-step alignment method in an embodiment of the present invention;

[0026] Figure 6 A schematic diagram of a structure in which structural alignment is achieved by aligning marks using a critical dimension alignment method in an embodiment of the present invention;

[0027] Figure 7 It is a structural schematic diagram of a back side alignment structure for realizing structural alignment in an embodiment of the present invention.

[0028] Figure 8 It is a structural schematic diagram of an alignment assembly in an embodiment of the present invention.

[0029] Fig. 9 It is a schematic diagram of another structure of alignment assembly in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0032] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] Example 1

[0034] like Figure 1-Figure 9 As shown,

[0035] A high-precision alignment and assembly method based on micro-nano technology comprises the following steps:

[0036] One-step alignment method: When preparing a complete electron gun structure, the corresponding alignment symbol is marked on the electron gun. At this time, the alignment symbol of the slow-wave structure is aligned with the alignment symbol of the electron gun to achieve alignment and assembly of the micro-nano structure.

[0037] Two-step alignment method: While preparing the responsive electron gun and slow-wave structure, prepare the alignment mark. This step can be completed in the same process step. At the same time, according to the designed size parameters, the alignment mark is positioned on the alignment layer substrate. Its size positioning is the same as that of the micro-nano structure and the slow-wave structure.

[0038] Critical dimension alignment method: The method is the same as the one-step alignment method, and the alignment symbol is replaced with the critical dimension of the structure, such as trench, right angle, edge, sidewall, etc.

[0039] According to the designed size parameters, the alignment mark is positioned and prepared on the alignment layer substrate, and its size positioning is the same as that of the micro-nano structure and the slow-wave structure. The alignment of the alignment mark is achieved by using a photolithography device or a bonding device, which can achieve high-precision structural alignment.

[0040] When the structure is opaque, an alignment symbol is prepared on the back of the structure, an alignment mark is prepared on the alignment layer substrate, and the alignment of the metal structure is achieved through a back microscope. When preparing a light-transmitting structure, an alignment mark is marked on the prepared electron gun and slow-wave structure at the same time, and an alignment mark is prepared on the alignment layer substrate. After the three are aligned in the lithography machine microelectronic device, the structure is assembled by bonding to achieve high-precision traveling wave tube alignment and assembly. Assembly methods also include bonding and high-precision pin hole micro-nano process assembly methods.

[0041] Alignment marks include alignment mark alignment, off-axis alignment, on-axis alignment, laser scanning video image alignment or grating alignment.

[0042] An alignment mark for high-precision alignment assembly based on micro-nano technology comprises an alignment layer substrate, an electron gun alignment mark arranged on the alignment layer substrate, and a slow-wave structure mark arranged on the alignment layer substrate, wherein the electron gun alignment mark and the slow-wave structure mark are arranged correspondingly.

[0043] The invention discloses an application of a high-precision alignment and assembly method based on micro-nano technology, which is applied to the alignment and assembly of microstructure devices with high frequency, micro size and high process precision requirements. It is also applied to the alignment and assembly of devices using slow wave structures, magnetic focusing systems and collector components, or high-frequency waveguide devices.

[0044] In the design of traveling wave tubes in lower frequency bands, due to the large critical dimensions, the design and manufacture of traveling wave tubes are mainly completed by manual operation. The existing traveling wave tube assembly method often adopts the method of digital machining. The existing milling processing technology adopts the method of pin hole alignment in the assembly process of traveling wave tubes. The pin connection method is as follows Figure 1As shown, this method can effectively improve the production efficiency and quality of the traveling wave tube. However, when the operating frequency of the traveling wave tube rises to the terahertz frequency band, the size of the high-frequency terahertz device is greatly reduced, and the alignment error of the pin hole connection method can only be maintained at the order of tens of microns or several microns, which cannot meet the needs of traveling wave tube manufacturing. Therefore, limited by the precision of processing equipment and assembly equipment, there is a large error in the assembly accuracy of the traveling wave tube. For example, through the method adopted in patent CN202996763U, the concentricity of the electron beam channel between the electron gun and the slow-wave system is guaranteed, with an accuracy of more than 0.02mm. In the 220GHz traveling wave tube manufactured by nano CNC milling technology, the structural dimensions of the traveling wave tube slow-wave structure and the electron gun are at the millimeter level, and the assembly accuracy of the milling technology is maintained at tens of microns, with a certain error.

[0045] The existing processing schemes of the traveling wave tube slow-wave structure and the electron gun can be realized by using micro-nano processing technology. Therefore, in combination with the existing micro-nano processing technology, the present invention proposes a high-precision alignment and assembly scheme based on micro-nano processing technology. By utilizing photolithography and overlay alignment technology, the electron gun structure and the slow-wave structure are directly aligned or the alignment of the two is realized on the same alignment layer substrate. The two realize a high-precision alignment scheme through alignment symbols. If photolithography equipment is used for bonding, the error depends on the photolithography error. The present invention proposes a high-precision alignment and assembly scheme based on micro-nano technology, and adopts the overlay alignment technology of micro-nano processing to greatly improve the assembly accuracy of micro-nano devices. The optical system overlay technology is combined with the traveling wave tube manufacturing process to form a new assembly alignment technology scheme.

[0046] like Figure 2 As shown in the figure, a planar schematic diagram of the electron gun and the slow-wave structure of the terahertz traveling wave tube is given. In actual assembly, it is necessary to solve the problem of alignment between the electron injection port of the electron gun and the entrance of the slow-wave structure during assembly. The traditional processing scheme uses pin holes to achieve the alignment of the electron gun structure and the slow-wave structure, but in high-frequency devices, since the key dimensions are reduced to the micron level, the traditional scheme cannot meet the requirements of high-precision assembly. Therefore, after the corresponding components are prepared by the micro-nano processing technology, the various components are aligned and assembled through the overlay technology in the micro-nano process. This scheme can be applied to the design and assembly scheme of high-frequency, micro-scale, and highly integrated traveling wave tubes, solving the problem of large errors during the assembly of traditional traveling wave tubes.

[0047] The present invention solves the problem of high-frequency traveling wave tube assembly alignment through an overlay scheme, such as Figure 3As shown, there are alignment marks (1-2) between the alignment layer substrate and the electron gun, and alignment marks (1-3) between the alignment layer substrate and the slow-wave structure. The overlay alignment marks are formed during the micro-nano process preparation of each component. By aligning the alignment marks between the structure and the alignment layer, after the process preparation, the alignment marks left during the micro-nano process of each component are aligned with the alignment layer substrate, so that the high-frequency traveling wave tube electron gun and the slow-wave structure can be aligned within the range allowed by the error accuracy.

[0048] Here is a commonly used alignment scheme between the electron gun and the slow-wave structure, such as Figure 4 As shown, while preparing the responsive electron gun and the slow-wave structure, the alignment mark is prepared, and this step can be completed in the same process step. At the same time, according to the designed size parameters, the positioning preparation of the alignment mark is completed on the alignment layer substrate. Its size positioning is the same as that of the micro-nano structure and the slow-wave structure. This scheme is often used in devices prepared by micro-nano processing. Since the error of the device prepared by micro-nano processing itself is small, when realizing the alignment and assembly of the electron gun and the slow-wave structure alignment port, the alignment between the two is converted into the assembly of the two with the alignment layer substrate, which can be regarded as the alignment between the two layers of alignment marks. The alignment of the alignment marks is often achieved by photolithography equipment, so high-precision structural alignment can be achieved.

[0049] This alignment method can also be applied to components such as slow-wave structures, magnetic focusing systems, and collectors, and can also be extended to the alignment and assembly of high-frequency waveguide devices. It should be noted that this assembly scheme has high requirements for the design and preparation of structural devices. High-frequency micro-nano structure devices prepared based on micro-nano processing schemes (UV-LIGA\DRIE, etc.) can meet the assembly requirements. In addition, high-precision processed micro-nano devices can also meet the needs of this experiment. In this embodiment, the slow-wave structure based on micro-nano processing has gradually matured, but the scheme for preparing electron guns and other components based on micro-nano structures is still under development. By assembling the above scheme with the alignment scheme in micro-nano processing, the preparation and alignment problems of high-frequency traveling wave tubes can be solved, which has extremely high engineering application value.

[0050] In the assembly of actual devices, some micro-nano structures and waveguides are often metal structures. Therefore, the front alignment marks are often not transparent and cannot be aligned. Therefore, a solution for back alignment to achieve metal micro-nano structure alignment is given here. Since photolithography equipment or other microelectronic devices usually have the function of back-end microscopes and can achieve structure alignment on both the front and back sides, we can prepare alignment marks on the back of the structure when the structure is not transparent, such as Figure 5 As shown, alignment symbols are also prepared on the alignment layer substrate, so that the alignment of the metal structure can be achieved through a backside microscope.

[0051] like Figure 6As shown, an assembly process of an electron gun and a slow-wave structure of a micro-nano processing stroke adopts a back-alignment scheme, and alignment marks 2 and 3 are marked on the prepared electron gun and the slow-wave structure, and alignment marks 1 and 3 are prepared on the alignment layer substrate. After alignment is achieved in a microelectronic device such as a lithography machine, the structure is assembled by bonding to achieve alignment and assembly of a high-precision traveling wave tube. After alignment is completed, the corresponding assembly means are not limited to bonding, high-precision pin holes, etc., and common micro-nano process assembly methods can be used to assemble both of them and can be applied to the present invention.

[0052] The core point of the present invention is to use micro-nano technology for high-precision assembly alignment scheme, which is mainly used in the alignment and assembly field of microstructure devices with high frequency, micro size and high process precision requirements. By using the alignment symbols commonly used in micro-nano technology, the alignment of the two waveguide structure ports is converted into the alignment of the plane alignment symbol, and the precise assembly of high-frequency small-size structural devices is realized. The error depends on the error of high-precision equipment (such as lithography equipment, bonding equipment, etc.), and the accuracy is much higher than the traditional alignment assembly scheme. The assembly can be assembled by micro-nano technology such as bonding, or it can be assembled by pin hole fine assembly after achieving high-precision alignment. The present invention can greatly improve the alignment and assembly accuracy, effectively improve the utilization efficiency of the signal, reduce the loss of the signal, and improve the overall gain and output power. It overcomes the problem of alignment and assembly difficulties of high-frequency band high-power micro-size. This scheme can be applied to the alignment and assembly fields of waveguide structures, traveling wave tube devices, antennas and other devices, and can be applied to high-frequency band high-output power application scenarios such as satellite communications, 6G base stations, and intersatellite alignment.

[0053] The alignment technology in the present invention not only includes the alignment of the traveling wave tube electron gun and the slow wave structure using the overlay mark technology, but also can be used for alignment and assembly that requires microscale and high precision. Such as vacuum electronic devices, waveguides, antennas, etc. The alignment scheme is not limited to alignment symbols. The current wide range of micro-nano processing alignment methods can be applied to this patent, including off-axis alignment, coaxial alignment, laser scanning video image alignment, grating alignment, etc. The present invention is not limited to the terahertz frequency band, and the alignment of the high-frequency micro-nano structure electron gun and the traveling wave tube slow wave structure can adopt this scheme. The present invention uses the electron gun structure and the slow wave structure as examples to illustrate the structural alignment. In fact, other components of the traveling wave tube (magnetic focusing system, collector, etc.) can be components prepared by micro-nano processing, and the alignment scheme can also be used during alignment. The assembly scheme of the present invention after alignment is not limited to the bonding method, and high-precision pin holes and assembly methods in micro-nano processing can also be applied to the present invention.

[0054] The advantages of the present invention are that by utilizing the alignment symbols commonly used in micro-nano technology, the alignment of the two waveguide structure ports is converted into the alignment of the plane alignment symbols, so as to realize the precise assembly of high-frequency and micro-sized structural devices, and greatly improve the accuracy of alignment and assembly. It can realize the assembly requirements of miniaturized and integrated traveling wave tubes, effectively improve the utilization efficiency of signals, reduce signal loss, and improve the overall gain and output power.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-precision alignment and assembly method based on micro-nano technology, characterized in that: The steps include: S1, after preparing the electron gun, forming a corresponding alignment mark on the electron gun; S2, slow-wave structure preparation corresponding alignment marks; S3, aligning the alignment mark of the slow-wave structure with the alignment mark of the electron gun to achieve alignment molding; In S1 and S2, while preparing the corresponding electron gun and slow-wave structure, an alignment mark is prepared. At the same time, the alignment mark is positioned and prepared on the alignment layer substrate according to the designed size parameters, and its size positioning is the same as that of the micro-nano structure and the slow-wave structure; Alignment marks are marked on the prepared electron gun and slow-wave structure at the same time, and alignment marks are prepared on the alignment layer substrate at the same time. After the three are aligned in the microelectronic device of the lithography machine, the structures are assembled by bonding to achieve the alignment and assembly of the high-precision traveling wave tube; When the structure is opaque, an alignment symbol is prepared on the back of the structure, an alignment mark is prepared on the alignment layer substrate, and the alignment of the metal structure is achieved through a microscope; the alignment mark includes alignment symbol alignment, off-axis alignment, on-axis alignment, laser scanning video image alignment or grating alignment.

2. The high-precision alignment and assembly method based on micro-nano technology according to claim 1, characterized in that: The alignment of the alignment marks is achieved using micro-nano devices to achieve high-precision structural alignment.

3. The high-precision alignment and assembly method based on micro-nano technology according to claim 1, characterized in that: Assembly methods also include bonding and high-precision pin hole micro-nano process assembly.

4. Application of the high-precision alignment and assembly method based on micro-nano technology according to any one of claims 1 to 3, characterized in that: Applied to the alignment and assembly of high-frequency, micro-sized micro-structure devices.

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