阅读说明：本技术 一种在尖锥形陶瓷腔体内壁制备微细金属涂层图案的方法 (Method for preparing fine metal coating pattern on inner wall of pointed conical ceramic cavity ) 是由 刘波 朱海红 金凡亚 但敏 于 2020-07-21 设计创作，主要内容包括：本发明提出了一种在尖锥形陶瓷腔体内壁制备微细金属涂层图案的方法,涉及超材料隐身技术领域。本发明提供的在尖锥形陶瓷腔体内壁制备金属涂层微细金属涂层图案的方法,包括如下步骤,激光从尖锥形陶瓷腔体外部穿透尖锥形陶瓷腔体,对尖锥形陶瓷腔体的内壁上的金属涂层进行激光反向刻蚀,通过选择性扫描在尖锥形陶瓷腔体内壁获得微细金属涂层图案,所述尖锥形陶瓷腔体的壁的厚度为3-15mm。本发明的优点在于,突破传统方法的加工技术壁垒,首次提出利用激光反向刻蚀尖锥形陶瓷腔体内壁的金属涂层,解决了尖锥形陶瓷腔体内壁难构筑微细金属涂层图案的技术难题,便于进一步制备FSS超材料,为尖锥形陶瓷腔雷达罩隐身提供技术基础。(The invention provides a method for preparing a fine metal coating pattern on the inner wall of a pointed conical ceramic cavity, and relates to the technical field of metamaterial stealth. The invention provides a method for preparing a metal coating micro metal coating pattern on the inner wall of a pointed conical ceramic cavity, which comprises the following steps of enabling laser to penetrate through the pointed conical ceramic cavity from the outside of the pointed conical ceramic cavity, carrying out laser reverse etching on a metal coating on the inner wall of the pointed conical ceramic cavity, and obtaining the micro metal coating pattern on the inner wall of the pointed conical ceramic cavity through selective scanning, wherein the thickness of the wall of the pointed conical ceramic cavity is 3-15 mm. The method has the advantages that the processing technology barrier of the traditional method is broken through, the metal coating of the inner wall of the pointed conical ceramic cavity is reversely etched by utilizing the laser, the technical problem that a fine metal coating pattern is difficult to construct on the inner wall of the pointed conical ceramic cavity is solved for the first time, the FSS metamaterial is convenient to further prepare, and a technical basis is provided for hiding the radar cover of the pointed conical ceramic cavity.)

1. A method for preparing a fine metal coating pattern on the inner wall of a sharp-cone-shaped ceramic cavity is characterized by comprising the following steps of enabling laser to penetrate through the sharp-cone-shaped ceramic cavity from the outside of the sharp-cone-shaped ceramic cavity to be focused on the inner wall of the cavity, carrying out laser reverse etching on a metal coating on the inner wall of the sharp-cone-shaped ceramic cavity, and obtaining the fine metal coating pattern on the inner wall of the sharp-cone-shaped ceramic cavity, wherein the thickness of the wall of the sharp-cone-shaped ceramic cavity is 3-15 mm.

2. The method of claim 1, wherein the laser used in the laser reverse etching process has a center wavelength of 100nm to 2000nm and a pulse width of 10ns to 1000 ns; the scanning speed of the laser is 1 mm/s-1000 mm/s, the scanning interval is 0.01 mm-1 mm, and the defocusing amount is-10 mm-0 mm.

3. The method according to claim 1 or 2, characterized in that:

before the laser reverse etching step, the method also comprises the following steps:

deposition of metal coating: preparing a modified layer on the surface of a base material by utilizing ion implantation to obtain the base material containing the modified layer, and then depositing a seed crystal layer and a thickening coating on the base material containing the modified layer to obtain a first base material to be subjected to laser reverse etching;

deposition of protective glue: arranging a protective adhesive on the surface of the metal coating of the first substrate to be subjected to laser reverse etching to obtain a second substrate to be subjected to laser reverse etching;

and after the substrate II to be subjected to laser reverse etching is subjected to laser reverse etching, cleaning the protective glue, namely obtaining a fine metal coating pattern on the inner wall of the pointed conical ceramic cavity.

4. The method of claim 3, wherein the metal coating comprises any one of an Ag-based coating, a Cu-based coating, an Au-based coating, and an Al-based coating.

5. The method of claim 4, wherein the metal coating deposition process comprises the steps of:

a. cleaning the surface of the base material:

cleaning a base material, then drying the base material in vacuum, and after drying, putting the base material into bias reverse sputtering equipment for bias reverse sputtering treatment to obtain a pretreated base material;

vacuum degree in bias reverse sputtering process is less than 6X 10^-3Pa, the time for cleaning the base material by bias reverse sputtering is 8-12 min, the bias of reverse sputtering is-550-450V, the air pressure in the bias reverse sputtering process is 2.8-3.2 Pa, and the working atmosphere is Ar;

b. plasma immersion ion implantation:

inert gas is introduced to adjust the vacuum degree to 1.8-2.2 multiplied by 10^-2Pa, adjusting the filament current, the arc voltage and the extraction voltage in sequence, then alternately adjusting the suppression voltage and the acceleration voltage, injecting ions into the surface layer of the sample by utilizing ion injection and plasma deposition, and obtaining a base material containing a modified layer after the treatment is finished;

the ions comprise any one of Ti, Ta and NiCr;

the filament current is 10-14A, the arc voltage is 100-140V, and the extraction voltage is 0.5-0.8 kV; the suppression voltage is 1-4 kV, the acceleration voltage is 60-80 kV, and the difference value between the acceleration current and the suppression current is 1-4 mA; the purity of the inert gas is more than 99 percent; the inclined implantation angle of the inert ions is 30-90 degrees, the acceleration voltage of 60-80 kV corresponds to the ion beam energy of 60 keV-80 keV, and the ion implantation depth is 50-90 nm; the implantation time is 3-30min, and the corresponding ion beam dose is 1 × 10¹⁶cm^-2～1×10¹⁷cm^-2；

c. Depositing a metal seed layer

Using radio frequency reactionsAnd (c) magnetron sputtering technology, depositing a metal seed crystal layer on the substrate containing the modified layer obtained in the step (b) by using a magnetron metal (X) alloy target, wherein X comprises one or two of Ti, Ta and Zr, closing the magnetron metal (X) alloy target after deposition is finished, and adjusting the vacuum degree of a reaction chamber to be 4-5X 10^-4Pa, cooling, and taking the substrate out of the furnace to obtain the substrate containing the modified layer and the seed crystal layer; the metal in the magnetic control metal (X) alloy target is any one of Ag, Cu, Au and Al;

the sputtering power of the magnetic control metal (X) alloy target is 120-150W; the bias voltage is-100 to-300V; the deposition time is 30-40 seconds; the working atmosphere Ar has a working vacuum degree of 0.40-0.50 Pa.

6. The method of claim 5, wherein the step a, cleaning the substrate comprises cleaning the substrate in an ultrasonic apparatus sequentially using acetone and absolute ethyl alcohol to remove surface impurities, and then cleaning with deionized water; the vacuum degree of vacuum drying in the step a is less than 1 multiplied by 10^-2Pa, temperature of 100 deg.C, vacuum degree of 5 × 10 during bias reverse sputtering^-3Pa; the time for cleaning the substrate by bias reverse sputtering is 10min, the bias of reverse sputtering is-500V, and the air pressure in the process of bias reverse sputtering is 3.0 Pa.

7. The method of claim 5, wherein in the step b, the degree of vacuum is 2 x 10^-2Pa, the filament current is 12A, the arc voltage is 120V, and the lead-out voltage is 0.5-0.7 kV; alternately adjusting the suppression voltage and the acceleration voltage, wherein the suppression voltage is 3kV, the acceleration voltage is 70kV, and the difference value between the acceleration current and the suppression current is 3 mA; the purity of the inert gas is more than 99.99 percent; the inclined implantation angle of the inert ions is 60 degrees, the acceleration voltage of 70kV corresponds to the energy of an ion beam of 70keV, and the ion implantation depth is 70 nm; the implantation time is 10-20min, and the corresponding ion beam dose is 4 x 10¹⁶cm^-2-8×10¹⁶cm^-2。

8. The method of claim 5, wherein the cooling in step c is performed under a reaction chamber vacuum of 4.5%×10^-4Naturally cooling along with the furnace under Pa; the sputtering power of the magnetic control metal (X) alloy target is 140W, the bias voltage is-200V, and the metal is Ag; the flow rate of Ar was 180 Sccm.

9. The method of claim 5, wherein: the purity of the magnetic control metal (X) alloy target is 99.99%, and the atomic percentage of X in the metal (X) alloy target is 2-7%.

10. The method of claim 5, wherein: the thickness of the protective glue is 2-50 μm.

Technical Field

The invention relates to the technical field of metamaterial stealth, in particular to a method for preparing a fine metal coating pattern on the inner wall of a pointed conical ceramic cavity.

Background

The Frequency Selective Surface (FSS) is a microwave periodic structure, and any conductor patch or aperture structure periodically distributed on a plane can generate diffraction phenomena on electromagnetic waves from microwave to optical wave bands. Resonance occurs when the cell size is an integer multiple of half the wavelength of the incident wave. When the array elements of the frequency selective surface resonate for an incident wave of a certain frequency, the incident wave is totally reflected or totally transmitted, while an incident wave deviating from the resonant frequency can be partially passed or partially reflected, so that the FSS can act as a spatial filter. The FSS applied to the stealth technology has incomparable advantages of other stealth technologies, such as wide wave band and good reliability, does not need to change the appearance of a machine body and a manufacturing process thereof, does not increase resistance and weight, and has good application prospect. The antenna housing can be combined with the FSS to manufacture a Frequency Selective antenna housing (FSR), so that an enemy radar wave band is selectively shielded and penetrates through a own radar wave band, and the stealth of the radar housing is realized. From the material design and preparation perspective, the stealth radar and the antenna cover based on the FSS are artificial electromagnetic materials formed by coating sub-wavelength regular metal fine pattern (wire) structural units on the inner surface of a specific wave-transparent ceramic cover (as shown in fig. 1).

However, because some non-planar special-shaped structures or pointed cone-shaped structures exist on the body, the full coverage of the FSS-based metamaterial on the body radar has great technical difficulty. The traditional FSS metamaterial preparation technology basically obtains the FSS-based metamaterial by metalizing and patterning the outer surface of planar ceramic through a glue coating-photoetching mask technology. The conventional techniques include screen printing metal microfabrication technology, liquid phase deposition technology and advanced vacuum deposition technology such as vacuum evaporation, ion implantation and plasma deposition (such as PVD/CVD), but the aforementioned techniques have the following disadvantages when used for preparing a fine coating pattern on the inner wall surface of a tapered ceramic cavity:

the screen printing metal micro-machining technology is mature, the fineness of the existing printing technology in the common field is met, such as a high-precision metal etching machining process (application number CN201410261133.4), but for a ceramic cavity with a sharp cone-shaped or special-shaped structure, the printing preparation of the FSS metamaterial cannot be realized on the inner wall of the ceramic cavity due to the fact that relevant equipment and operation processes of the screen printing are severely limited by the geometric shape and the size of the sharp cone-shaped ceramic cavity or the special-shaped narrow structure.

The liquid phase deposition method is to utilize slow hydrolysis of metal fluoride to directly grow a corresponding metal oxide film on the surface of a hydrophilic substrate placed in a solution. At present, the liquid phase deposition method has been successfully applied to SiO₂、TiO₂、SnO₂And preparing oxide films of metals such as Fe, V, Mn, Nb, Zr, Ni, Ta and the like. Although there are other various methods of liquid-phase depositing a metal coating such as the electrodeposition method such as the "metal electrodeposition method" (application No. CN103517571A), a metal electrodeposition deposition method of an insulating substrate is provided, and it can be seen that if a precise mask pattern is absent in a ceramic cavity of a pointed cone-shaped or shaped structure, a fine metal coating pattern having a controlled precision cannot be prepared at all in the ceramic cavity of a pointed cone-shaped or shaped structure by the liquid-phase method.

The patent discloses a visible near-infrared band absorption film system structure (Chinese patent application No. CN201420028381.X), which discloses that a metal film layer and a medium film layer are sequentially grown on any substrate by adopting vapor deposition and liquid deposition, and then a metal particle disorder distribution layer is grown on the medium film layer by utilizing vapor deposition or vapor deposition combined with an annealing process. Its advantages are simple process, low cost, insensitivity to normal, angle and high controllability. However, if the ceramic cavity with the tapered or irregular structure is lack of a precise mask pattern, the precise controllable fine metal coating pattern cannot be prepared by vapor deposition or vapor deposition combined with an annealing process in the same way. Therefore, the direct application of the liquid phase deposition and vapor deposition techniques to the preparation of metal thin films and even fine metal coating patterns in tapered ceramic cavities still has many technical obstacles.

Although advanced vacuum deposition techniques such as vacuum evaporation, ion implantation, and plasma deposition (such as PVD/CVD) can overcome some of the aforementioned defects to some extent, and can prepare high-precision metal patterns on the surface of a material, a method for precisely preparing mask patterns in a tapered ceramic cavity is lacking at present, and thus, a fine metal coating pattern with high precision, good conductivity, and high reliability cannot be obtained in the tapered ceramic cavity. In addition, how to ensure that the ceramic/metal coating can adapt to high-temperature thermal shock (more than or equal to 800 ℃) and thermal stress after two materials with different components, structures and thermal expansion coefficients are combined cannot be realized, and the interface combination performance, the interface diffusion, the long-life service and the like of the ceramic/metal coating can be maintained, which are problems to be further overcome.

Therefore, the method for preparing the metal micro-fine metal coating pattern meeting the working conditions on the inner wall of the pointed conical ceramic cavity is developed, provides technical support for key ceramic metalized parts under high-temperature service conditions such as deep detection, air and space military reconnaissance and detection and the like, and has very important application value.

Disclosure of Invention

The invention aims to provide a method for preparing a fine metal coating pattern on the inner wall of a pointed conical ceramic cavity, which can construct the fine metal coating pattern in a special-shaped part and solve the technical problem that the inner wall of the pointed conical ceramic cavity is difficult to construct a fine pattern. The method is suitable for preparing a fine metal coating pattern on the inner wall of a pointed conical ceramic cavity with an opening at one end, in particular to a pointed conical ceramic component with a cone angle of 20-80 degrees.

The technical problem to be solved by the invention is realized by adopting the following technical scheme.

On one hand, the invention provides a method for preparing a fine metal coating pattern on the inner wall of a sharp-cone-shaped ceramic cavity, which comprises the following steps that laser penetrates through the sharp-cone-shaped ceramic cavity from the outside of the sharp-cone-shaped ceramic cavity to be focused on the inner wall of the cavity, and the fine metal coating pattern is obtained on the inner wall of the sharp-cone-shaped ceramic cavity after the metal coating on the inner wall of the sharp-cone-shaped ceramic cavity is subjected to laser reverse etching. And obtaining the required fine metal coating pattern by selective laser reverse etching.

Compared with the prior art, the embodiment of the invention has at least the following advantages or beneficial effects:

the method for preparing the superfine metal coating pattern on the inner wall of the pointed conical ceramic cavity, provided by the invention, firstly provides the metal coating on the inner wall of the pointed conical ceramic cavity by utilizing laser reverse etching, solves the technical problem that the superfine metal coating pattern is difficult to construct on the inner wall of the pointed conical ceramic cavity, is convenient for further preparing the FSS metamaterial, and provides a technical basis for hiding the pointed conical ceramic radome.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic structural diagram of a metamaterial in the background art of the present invention;

FIG. 2 is a schematic diagram of reverse laser reverse etching in example 1 of the present invention;

FIG. 3 is a schematic diagram of reverse laser reverse etching in example 1 of the present invention;

FIG. 4 is a schematic view of a reverse laser reverse etching workbench in embodiment 1 of the present invention;

FIG. 5 is a schematic flow chart I of the method in example 3 of the present invention;

FIG. 6 is a schematic flow chart II of the method in embodiment 3 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to specific examples.

The embodiment of the application provides a method for preparing a fine metal coating pattern on the inner wall of a sharp-cone-shaped ceramic cavity, which comprises the following steps that laser penetrates through the sharp-cone-shaped ceramic cavity from the outside of the sharp-cone-shaped ceramic cavity to focus on the inner wall of the cavity, the fine metal coating pattern is obtained on the inner wall of the sharp-cone-shaped ceramic cavity after the metal coating on the inner wall of the sharp-cone-shaped ceramic cavity is subjected to laser reverse etching, and the thickness of the wall of the sharp-cone-shaped ceramic cavity is 3-15 mm. The metal coating on the inner wall of the pointed conical ceramic cavity is reversely etched by utilizing laser, the technical problem that high-precision fine patterns are difficult to construct on the inner wall of the pointed conical ceramic cavity is solved, the FSS is convenient to further prepare, and a technical foundation is provided for invisibility of the inside of the pointed conical ceramic cavity, particularly the radome.

In some embodiments of the present invention, in the above method, a central wavelength of a laser used in the laser reverse etching process is 100nm to 2000nm, and a pulse width is 10ns to 1000 ns; the scanning speed of the laser is 1 mm/s-1000 mm/s, the scanning interval is 0.01 mm-1 mm, and the defocusing amount is-10 mm-0 mm. The process for constructing the pattern of the micro metal coating by reverse laser etching is realized by selecting laser with specific wavelength and power.

In some embodiments of the present invention, the method further comprises, before the step of laser back etching, the following steps of depositing a metal coating: preparing a modified layer on the surface of a base material by utilizing ion implantation to obtain the base material containing the modified layer, and then depositing a seed crystal layer and a thickening coating on the base material containing the modified layer to obtain a first base material to be subjected to laser reverse etching; deposition of protective glue: arranging a protective adhesive on the surface of the metal coating of the first substrate to be subjected to laser reverse etching to obtain a second substrate to be subjected to laser reverse etching; and after the substrate II to be subjected to laser reverse etching is subjected to laser reverse etching, cleaning the protective glue, namely obtaining a fine metal coating pattern on the inner wall of the pointed conical ceramic cavity. The method comprises the steps of depositing metal and protective adhesive in a pointed conical ceramic cavity, and obtaining a fine metal coating pattern through laser reverse etching, so that the construction of the high-temperature-resistant and high-conductivity fine metal coating pattern in the pointed conical ceramic cavity can be realized. Meanwhile, because the metal splashed in the laser reverse etching process is deposited on the surface of the protective adhesive, the protective adhesive is cleaned when cleaned, and the splashed metal can be completely sucked by adopting a general suction system, so that the high precision of the fine metal coating pattern is ensured.

In some embodiments of the present invention, in the above method, the metal coating layer includes any one of an Ag-based coating layer, a Cu-based coating layer, an Au-based coating layer, and an Al-based coating layer. Of the metal coatings, Ag is preferable in view of practical circumstances, and a metal coating resistant to high temperature, high conductivity, and high electrical conductivity can be obtained.

In some embodiments of the present invention, in the above method, the metal coating deposition process includes the following steps: a. cleaning the surface of the base material: cleaning a base material, then drying the base material in vacuum, and after drying, putting the base material into bias reverse sputtering equipment for bias reverse sputtering treatment to obtain a pretreated base material; vacuum degree in bias reverse sputtering process is less than 6X 10^-3Pa, the time for cleaning the base material by bias reverse sputtering is 8-12 min, the bias of reverse sputtering is-550-450V, the air pressure in the bias reverse sputtering process is 2.8-3.2 Pa, and the working atmosphere is Ar; b. plasma immersion ion implantation: inert gas is introduced to adjust the vacuum degree to 1.8-2.2 multiplied by 10^-2Pa, regulating filament current, arc voltage and extraction voltage in sequence, regulating suppression voltage and acceleration voltage alternately, and utilizing ionsInjecting ions into the surface layer of the sample by injection and plasma deposition, and obtaining a base material containing a modified layer after the treatment is finished; the ions comprise any one of Ti, Ta and NiCr; the filament current is 10-14A, the arc voltage is 100-140V, and the extraction voltage is 0.5-0.8 kV; the suppression voltage is 1-4 kV, the acceleration voltage is 60-80 kV, and the difference value between the acceleration current and the suppression current is 1-4 mA; the purity of the inert gas is more than 99 percent; the inclined implantation angle of the inert ions is 30-90 degrees, the acceleration voltage of 60-80 kV corresponds to the ion beam energy of 60 keV-80 keV, and the ion implantation depth is 50-90 nm; the implantation time is 3-30min, and the corresponding ion beam dose is 1 × 10¹⁶cm^-2～1×10¹⁷cm^-2(ii) a c. Depositing a metal seed crystal layer: adopting a radio frequency reaction magnetron sputtering technology, depositing a metal seed crystal layer on the base material containing the modification layer obtained in the step b by using a magnetron metal (X) alloy target, wherein X comprises one or two of Ti, Ta and Zr, closing the magnetron metal (X) alloy target after deposition is finished, and adjusting the vacuum degree of a reaction chamber to be 4-5 multiplied by 10^-4Pa, cooling, and taking the substrate out of the furnace to obtain the substrate containing the modified layer and the seed crystal layer; the metal in the magnetic control metal (X) alloy target is any one of Ag, Cu, Au and Al; the sputtering power of the magnetic control metal (X) alloy target is 120-150W; the bias voltage is-100 to-300V; the deposition time is 30-40 seconds; the working vacuum degree is 0.40-0.50 Pa.

In some embodiments of the present invention, in the above method, the step a of cleaning the substrate includes sequentially cleaning the substrate with acetone and absolute ethyl alcohol in an ultrasonic apparatus to remove surface impurities, and then cleaning with deionized water; the vacuum degree of vacuum drying in the step a is less than 1 multiplied by 10^-2Pa, temperature of 100 deg.C, vacuum degree of 5 × 10 during bias reverse sputtering^-3Pa; the time for cleaning the substrate by bias reverse sputtering is 10min, the bias of reverse sputtering is-500V, and the air pressure in the process of bias reverse sputtering is 3.0 Pa.

In some embodiments of the present invention, in the above method, in the step b, the degree of vacuum is 2 × 10^-2Pa, the filament current is 12A, the arc voltage is 120V, and the lead-out voltage is 0.5-0.7 kV; alternately regulating the suppression voltage of 3kV and the acceleration voltageThe voltage is 70kV, and the difference value between the accelerating current and the inhibiting current is 3 mA; the purity of the inert gas is more than 99.99 percent; the inclined implantation angle of the inert ions is 60 degrees, the acceleration voltage of 70kV corresponds to the energy of an ion beam of 70keV, and the ion implantation depth is 70 nm; the implantation time is 10-20min, and the corresponding ion beam dose is 4 x 10¹⁶cm^-2-8×10¹⁶cm^-2。

In some embodiments of the present invention, the cooling in step c is performed in a reaction chamber having a vacuum of 4.5X 10^-4Naturally cooling along with the furnace under Pa; the sputtering power of the magnetic control metal (X) alloy target is 140W, the bias voltage is-200V, and the metal is Ag; the flow rate of Ar was 180 Sccm.

In some embodiments of the present invention, the purity of the metal (X) alloy target is 99.99%, and the atomic percentage of X in the metal (X) alloy target is 2-7%.

In some embodiments of the present invention, in the above method, the protective glue has a thickness of 2 μm to 50 μm.

The features and properties of the present invention are described in further detail below with reference to examples.