Diamond microwave and millimeter wave power attenuator and manufacturing method thereof
By using laser engraving and magnetron sputtering technology to form TaN and Au films on diamond substrates, the existing microwave millimeter wave high-power attenuators are solved, and a miniaturized, high-power and widely used microwave millimeter wave power attenuators are realized.
Patent Information
- Application Number
- CN202510325049.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-19
- Publication Date
- 2025-06-06
AI Technical Summary
Existing microwave millimeter-wave high-power attenuators have high prices and huge sizes, which are difficult to meet the needs of high performance and low cost.
The diamond microwave millimeter wave power attenuator and its manufacturing method are used to form TaN and Au films on the diamond substrate through laser engraving and magnetron sputtering technology to achieve a miniaturized and high-power attenuator design.
It has achieved miniaturized, serialized, and high-power microwave millimeter wave power attenuators, with the power increased from 2W to 150W, the frequency range expanded to DC-40GHz, and the volume reduced to one-fifth of similar products. It is suitable for a variety of RF microwave products.
Smart Images
Figure CN120109472A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of power attenuators, in particular to a diamond microwave millimeter wave power attenuator and a manufacturing method thereof. Background Art
[0002] As a key microwave technology component, the core function of the power attenuator is to introduce a preset attenuation within a specific frequency range. This circuit element plays a vital role in microwave and millimeter wave communications, radar systems, test instruments and other fields. It is indicated by the decibel number of the introduced attenuation and the ohm number of its characteristic impedance. It effectively reduces the microwave energy by absorbing, reflecting or cutting off electromagnetic waves, thereby balancing the signal level in the signal chain, expanding the system dynamic range, achieving impedance matching, and implementing a variety of calibration techniques in terminal applications. Specifically, power attenuators are widely used in cable TV systems to meet the level requirements of multiple ports, such as the control of the input and output levels of the amplifier and the control of the branch attenuation. In microwave testing, attenuators are even more indispensable and are used to protect test instruments from damage caused by excessive power. In addition, in radar anti-interference systems, the jump attenuator, as a variable attenuator with a sudden change in attenuation, does not introduce attenuation at ordinary times, but suddenly increases attenuation when encountering external interference, thereby effectively resisting interference.
[0003] The microwave millimeter wave high-power attenuators on the current market generally face the problems of high price and large size, which seriously restricts their integration needs in some high-power and high-frequency application scenarios in China. With the rapid development of modern electronic technology, especially in the fields of 5G communication, satellite communication and high-precision radar systems, higher requirements are put forward for the performance of attenuators, including higher power capacity, wider frequency response range and more compact packaging volume. In response to this challenge, scholars and industrial circles at home and abroad have launched research and design of thin film attenuators. With its compact structure and easy integration, thin film attenuators are regarded as an effective way to solve the problem of large size of current high-power attenuators. However, although some progress has been made in the design of thin film attenuators at home and abroad, there is still a lack of a simple and effective method to quickly derive the design model of microwave millimeter wave high-power attenuation. This leads to a long design cycle and high cost of thin film attenuators, which makes it difficult to meet the urgent market demand for high-performance and low-cost attenuators. Summary of the invention
[0004] 1. Technical issues to be solved
[0005] In view of the deficiencies in the prior art, the present invention provides a diamond microwave millimeter wave power attenuator and a method for manufacturing the same, which has the advantages of small size and solves the problem of manufacturing difficulties.
[0006] (II) Technical solution
[0007] To achieve the above object, the present invention provides the following technical solution: comprising a substrate, the top surface of the substrate is provided with a groove formed by laser engraving technology, the outer surface of the substrate is provided with a base layer formed by sputtering technology, the top surface of the substrate is provided with a TaN film formed by sputtering technology, the outer surface of the TaN film is provided with an Au film formed by sputtering technology, and further comprising the following steps:
[0008] Step 1) Preparation of substrate 1: Cut the substrate 1 of standard thickness by a diamond cutting machine, and polish and grind the substrate 1 by a post-diamond polishing device.
[0009] Step 2) Laser grooving: According to the performance requirements of the attenuator, use CAD to design the appropriate circuit pattern, and use laser grooving or punching technology to form the required circuit structure on the substrate.
[0010] Step 3) Magnetron sputtering primer: Use magnetron sputtering equipment to sputter a uniform layer of primer metal on the substrate.
[0011] Step 4) Sputtering TaN film: sputtering a TaN film on the diamond substrate.
[0012] Step 5) Photolithography: Use a mask and photolithography technology to form the desired circuit pattern on the TaN film.
[0013] Step 6) Sputtering Au film: Sputter a layer of Au film on the TaN film, and use a mask plate and photolithography technology to form a desired circuit pattern on the Au film.
[0014] Step 7) Sputtering to thicken the Au layer: sputtering a thickened Au layer on the Au film, and using etching technology to finely etch and adjust the Au layer to form a desired circuit structure.
[0015] Step 8) Testing: The manufactured chip diamond power attenuator is tested by using testing equipment such as a network analyzer and a power meter.
[0016] Preferably, in step 1), it is necessary to ensure that the thickness, size and flatness of the diamond substrate meet the design requirements to avoid defects such as cracks and inclusions on the substrate. In step 1), the grinding pressure and grinding time should be controlled during the polishing and grinding process to avoid scratches or excessive wear on the surface of the diamond substrate. At the same time, it is necessary to ensure that the surface finish of the polished diamond substrate meets the requirements.
[0017] Preferably, the steps 1), 2), 3) and 7) all require cleaning of the processed parts, and an ultrasonic cleaning machine is required for the cleaning.
[0018] Preferably, the mask plate processing design is required before the processing operations in step 4), step 5), step 6) and step 7) to ensure that the size, accuracy and position of the mask plate are consistent with the subsequent process requirements.
[0019] Preferably, during the laser grooving in step 2), it is necessary to ensure that the depth, width and position of the grooving or drilling meet the design requirements to avoid damage to the diamond substrate.
[0020] Preferably, after the sputtering operation in step 7 is completed, etching adjustment is performed to ensure that the depth, width and position of the etching meet the design requirements to avoid excessive damage to the Au layer.
[0021] Preferably, during the test in step 8), the stability and accuracy of the test environment should be ensured to obtain reliable test results. At the same time, necessary adjustments and optimizations should be made to the attenuator according to the test results.
[0022] (III) Beneficial effects
[0023] Compared with the prior art, the present invention provides a diamond microwave millimeter wave power attenuator and a manufacturing method thereof, which has the following beneficial effects:
[0024] 1. The diamond microwave millimeter wave power attenuator and its manufacturing method combine high-quality diamond semiconductor materials with microwave thin film technology, apply them to the field of microwave millimeter wave power attenuators, make them into patch type and chip type, achieve the effect of miniaturization, serialization, high power and wide application, and the chip type diamond microwave millimeter wave power attenuator is designed to adopt Π (PI) type in order to ensure its good performance and grounding characteristics. Through fine design, strict simulation and improved process realization, a miniaturized diamond microwave millimeter wave power attenuator is formed. According to the structural size of the optimized device, and according to the characteristics of the product and the characteristics of diamond, the laser processing technology is first used to pre-process grooves and holes on the diamond wafer, and then the magnetron sputtering technology is used to first make the bottom metal, back electrode and matching electrode on the double-sided polished diamond sheet, and then the radio frequency magnetron sputtering and mask patterning technology are used to prepare TaN film to form attenuators with various attenuation values, 0-10dB, 12dB, 15dB, 20dB, 30dB, and laser photolithography resistance adjustment technology is performed according to actual needs. After coating is completed, the matching load will be vacuum annealed at a temperature of 500 degrees Celsius to eliminate defects in the film and improve the stability of the device.
[0025] 2. Compared with similar BeO and ceramic sheet products, the diamond microwave millimeter wave power attenuator and its manufacturing method have increased its power from 2W to 150W and its frequency from DC-6GHz to DC-40GHz. Moreover, this invention has excellent heat dissipation, which reduces the size to one-fifth of similar products, or even smaller, making it very convenient to integrate into various radio frequency microwave products, as well as military, aerospace and other products; and due to the improvement of its volume and heat dissipation characteristics, the requirements for heat dissipation and power supply are reduced in system design and application, so that system performance is improved and energy consumption is reduced. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 A schematic diagram of the first perspective structure of the power attenuator proposed by the present invention;
[0027] Figure 2 A second perspective structural schematic diagram of the power attenuator proposed by the present invention;
[0028] Figure 3 The present invention provides a schematic structural diagram of a substrate.
[0029] In the figure: 1-substrate, 2-groove, 3-base layer, 4-TaN film, 5-Au film. DETAILED DESCRIPTION
[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not 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] See also Figure 1-3 , comprising a substrate 1, a groove 2 formed by laser engraving technology is formed on the top surface of the substrate 1, a base layer 3 formed by sputtering technology is provided on the outer surface of the substrate 1, a TaN film 4 formed by sputtering technology is provided on the top surface of the substrate 1, and an Au film 5 formed by sputtering technology is provided on the outer surface of the TaN film 4, and further comprising the following steps:
[0032] Step 1) Preparation of substrate 1: Cut a substrate of standard thickness using a diamond cutting machine, and polish and grind the substrate using a post-diamond polishing device.
[0033] Step 2) Laser grooving: According to the performance requirements of the attenuator, use CAD to design the appropriate circuit pattern, and use laser grooving or punching technology to form the required circuit structure on the substrate.
[0034] Step 3) Magnetron sputtering primer: Use magnetron sputtering equipment to sputter a uniform layer of primer metal on the substrate.
[0035] Step 4) Sputtering TaN film: sputtering a TaN film on the diamond substrate.
[0036] Step 5) Photolithography: Use a mask and photolithography technology to form the desired circuit pattern on the TaN film.
[0037] Step 6) Sputtering Au film: Sputter a layer of Au film on the TaN film, and use a mask plate and photolithography technology to form a desired circuit pattern on the Au film.
[0038] Step 7) Sputtering to thicken the Au layer: sputtering a thickened Au layer on the Au film, and using etching technology to finely etch and adjust the Au layer to form a desired circuit structure.
[0039] Step 8) Testing: The manufactured chip diamond power attenuator is tested by using testing equipment such as a network analyzer and a power meter.
[0040] The electrical components mentioned in this article are all connected to an external main controller and 220V mains electricity, and the main controller can be a conventional known device for controlling a computer or the like.
[0041] In a preferred embodiment: in step 1), it is necessary to ensure that the thickness, size and flatness of the diamond substrate meet the design requirements, and to avoid defects such as cracks and inclusions on the substrate. In step 1), the grinding pressure and grinding time must be controlled during the polishing and grinding process to avoid scratches or excessive wear on the surface of the diamond substrate. At the same time, it is necessary to ensure that the surface finish of the diamond substrate after polishing meets the requirements. Ensuring that the thickness, size and flatness of the diamond substrate meet the design requirements is the basis for manufacturing high-quality attenuators. By strictly controlling the grinding pressure and grinding time during the polishing and grinding process, scratches or excessive wear on the surface of the diamond substrate can be avoided, thereby ensuring that the surface finish of the diamond substrate after polishing meets the requirements. This helps to improve the performance and stability of the attenuator.
[0042] In a preferred embodiment: Step 1), Step 2), Step 3) and Step 7) all require cleaning of the processed parts, and an ultrasonic cleaner is required for cleaning. During the manufacturing process, cleaning is a key step to ensure that the parts are clean and free of impurities. The use of an ultrasonic cleaner can effectively remove dirt, grease and other impurities on the surface of the parts, providing a clean processing environment for subsequent processes. This helps to improve the manufacturing quality and performance of the attenuator.
[0043] In a preferred embodiment: the mask plate processing design is required before the processing operations in step 4), step 5), step 6) and step 7), and the size, accuracy and position of the mask plate must be ensured to be consistent with the subsequent process requirements. The mask plate processing design is the key to ensuring the accuracy of the subsequent processing operations and the accuracy of the position. By ensuring that the size, accuracy and position of the mask plate are consistent with the subsequent process requirements, errors and deviations in the processing process can be avoided, thereby improving the manufacturing accuracy and performance of the attenuator.
[0044] In a preferred embodiment: Step 2) during laser grooving, it is necessary to ensure that the depth, width and position of the grooving or drilling meet the design requirements to avoid damage to the diamond substrate. Laser grooving is one of the important steps in manufacturing the attenuator. By ensuring that the depth, width and position of the grooving or drilling meet the design requirements, damage to the diamond substrate can be avoided while ensuring that the performance of the attenuator meets expectations. This helps to improve the reliability and stability of the attenuator.
[0045] In a preferred embodiment: after step 7) the sputtering operation is completed, etching adjustment is performed to ensure that the depth, width and position of the etching meet the design requirements and avoid excessive damage to the Au layer. By ensuring that the etching adjustment is performed after the sputtering operation is completed, the depth, width and position of the etching can be controlled to avoid excessive damage to the Au layer. This helps to maintain the performance of the attenuator stable and increase its service life.
[0046] In a preferred embodiment: Step 8) during the test, the stability and accuracy of the test environment must be ensured to obtain reliable test results. At the same time, the attenuator must be adjusted and optimized as necessary according to the test results. Testing is a key step in verifying whether the attenuator performance meets expectations. Reliable test results can be obtained by ensuring the stability and accuracy of the test environment. By making necessary adjustments and optimizations to the attenuator according to the test results, its performance and stability can be further improved to meet actual application requirements.
[0047] Diamond microwave millimeter wave power attenuator is manufactured:
[0048] 1) First, a diamond substrate of standard thickness is manufactured and prepared, and then the diamond substrate is polished and ground to eliminate surface defects and improve the finish.
[0049] 2) Use the manufactured mask plate to perform laser grooving or drilling operations, and then perform magnetron sputtering operations. First, a 1000-angstrom thick nickel / titanium tungsten base metal is sputtered. According to the new design requirements, a new mask plate is manufactured and TaN film is sputtered. After the TaN film is sputtered, photolithography is performed to form the required circuit pattern.
[0050] 3) Redesign the mask plate and perform the sputtering of Au thin film to form a conductive layer. After the sputtering is completed, a second photolithography process is performed to further define the circuit pattern. In order to increase the thickness and conductivity of the conductive layer, the mask plate is redesigned and the sputtering thickening Au layer is performed. After the sputtering of the thickened Au layer is completed, etching adjustment is performed.
[0051] 4) Finally, the finished product is cleaned to remove surface residues and impurities. After cleaning, a performance test is performed to ensure that the performance of the attenuator meets the design requirements. According to the test results, the attenuator is adjusted and optimized as necessary.
[0052] In summary, the diamond microwave millimeter wave power attenuator and its manufacturing method combine high-quality diamond semiconductor materials with microwave thin film technology, apply them to the field of microwave millimeter wave power attenuators, make them into patch type and chip type, achieve miniaturization, serialization, high power and wide application effects, and the chip type diamond microwave millimeter wave power attenuator is designed to ensure its good performance and grounding characteristics. The Π (PI) type is adopted. Through fine design, strict simulation and improved process realization, a miniaturized diamond microwave millimeter wave power attenuator is formed. According to the structural size of the optimized device, and according to the product characteristics and the characteristics of diamond, firstly, grooves and holes are pre-processed on the diamond wafer by laser processing technology, and then magnetron sputtering technology is used to first make the bottom metal, back electrode and matching electrode on the double-sided polished diamond sheet, and then radio frequency magnetron sputtering and mask patterning technology are used to prepare TaN film, so that it forms attenuators with various attenuation values, 0-10dB, 12dB, 15dB, 20dB, 30dB, and laser photolithography resistance adjustment technology is performed according to actual needs. After the coating is completed, the matching load will be vacuum annealed at a temperature of 500 degrees Celsius to eliminate defects in the film and improve the stability of the device. Compared with similar BeO and ceramic sheet products, the power of the diamond microwave millimeter wave power attenuator and its manufacturing method is increased from 2W to 150W, and the frequency is extended from DC-6GHz to DC-40GHz. Moreover, this invention has excellent heat dissipation, which reduces the size to one-fifth of similar products, or even smaller, making it very convenient to integrate into various RF microwave products, as well as military, aerospace and other products; and due to the improvement of its volume and heat dissipation characteristics, the requirements for heat dissipation, power supply, etc. are reduced in system design and application, so that system performance is improved and energy consumption is reduced.
[0053] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise one" do not exclude the existence of other identical elements in the process, method, article or device including the elements.
[0054] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A diamond microwave millimeter wave power attenuator, characterized in that: The invention comprises a substrate (1), wherein the top surface of the substrate (1) is provided with a groove (2) formed by laser engraving technology, the outer surface of the substrate (1) is provided with a base layer (3) formed by sputtering technology, the top surface of the substrate (1) is provided with a TaN film (4) formed by sputtering technology, and the outer surface of the TaN film (4) is provided with an Au film (5) formed by sputtering technology.
2. The diamond microwave millimeter wave power attenuator according to claim 1, characterized in that: The material of the substrate (1) is diamond, and the thickness of the substrate (1) is 0.38 mm.
3. The diamond microwave millimeter wave power attenuator according to claim 1, characterized in that: The thickness of the base layer (3) is 1000 angstroms, and the material of the base layer (3) is nickel / titanium-tungsten alloy.
4. A method for manufacturing a diamond microwave millimeter wave power attenuator, used for the diamond microwave millimeter wave power attenuator as claimed in any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1) Preparation of substrate 1: Cut a substrate of standard thickness using a diamond cutting machine, and polish and grind the substrate using a post-diamond polishing device. Step 2) Laser grooving: According to the performance requirements of the attenuator, use CAD to design the appropriate circuit pattern, and use laser grooving or punching technology to form the required circuit structure on the substrate. Step 3) Magnetron sputtering primer: Use magnetron sputtering equipment to sputter a uniform layer of primer metal on the substrate. Step 4) Sputtering TaN film: sputtering a TaN film on the diamond substrate. Step 5) Photolithography: Use a mask and photolithography technology to form the desired circuit pattern on the TaN film. Step 6) Sputtering Au film: Sputter a layer of Au film on the TaN film, and use a mask plate and photolithography technology to form a desired circuit pattern on the Au film. Step 7) Sputtering to thicken the Au layer: sputtering a thickened Au layer on the Au film, and using etching technology to finely etch and adjust the Au layer to form a desired circuit structure. Step 8) Testing: The manufactured chip diamond power attenuator is tested by using testing equipment such as a network analyzer and a power meter.
5. The method for manufacturing a diamond microwave millimeter wave power attenuator according to claim 4, characterized in that: In the step 1), it is necessary to ensure that the thickness, size and flatness of the diamond substrate meet the design requirements to avoid defects such as cracks and inclusions on the substrate. In the step 1), the grinding pressure and grinding time must be controlled during the polishing and grinding process to avoid scratches or excessive wear on the surface of the diamond substrate. At the same time, it is necessary to ensure that the surface finish of the polished diamond substrate meets the requirements.
6. The method for manufacturing a diamond microwave millimeter wave power attenuator according to claim 4, characterized in that: The steps 1), 2), 3) and 7) all require cleaning of the processed parts, and an ultrasonic cleaning machine is required for the cleaning.
7. The method for manufacturing a diamond microwave millimeter wave power attenuator according to claim 4, characterized in that: Before performing processing operations in step 4), step 5), step 6) and step 7), the processing design of the mask plate must be carried out to ensure that the size, accuracy and position of the mask plate are consistent with the subsequent process requirements.
8. The method for manufacturing a diamond microwave millimeter wave power attenuator according to claim 4, characterized in that: In the step 2) of laser grooving, it is necessary to ensure that the depth, width and position of the grooving or drilling meet the design requirements to avoid damage to the diamond substrate.
9. The method for manufacturing a diamond microwave millimeter wave power attenuator according to claim 4, characterized in that: After the sputtering operation in step 7) is completed, etching adjustment is performed to ensure that the depth, width and position of the etching meet the design requirements to avoid excessive damage to the Au layer.
10. The method for manufacturing a diamond microwave millimeter wave power attenuator according to claim 4, characterized in that: During the test in step 8), the stability and accuracy of the test environment must be ensured to obtain reliable test results, and necessary adjustments and optimizations must be made to the attenuator based on the test results.