A kind of radiation-resistant thin film material and preparation method thereof

Abstract

The invention discloses a method for preparing a radiation-resistant thin film material, comprising the following steps: firstly depositing tungsten on a substrate by electron beam evaporation coating to form a base film; then depositing tungsten material on the base film again by magnetron sputtering coating to form a tungsten film; and sintering the film material having the tungsten film and the base film at 400-500°C to obtain the radiation-resistant thin film material. The method for preparing the radiation-resistant thin film material of the invention takes silicon as a substrate, and finally obtains a thin film material with silicon as a substrate through the steps of electron beam evaporation coating, magnetron sputtering, sintering, annealing treatment, etc., wherein a new α phase (diffraction peaks α(200), α(211), α(220)) appears in the thin film, and the β phase diffraction peak does not disappear, so there are coexisting phases α and β, that is, it has relatively excellent electrical properties and excellent mechanical properties.

Description

Technical Field

[0001] The invention relates to the technical field of nano material preparation, and in particular to a method for preparing a radiation-resistant metal nano film material and the radiation-resistant film material prepared by the preparation method. Background Art

[0002] Under the irradiation conditions of high-energy particles, different types of defects will appear inside metal-based structural materials. The large-scale aggregation of these irradiation-induced defects will cause damage, reduce the structural stability of the material, and thus seriously affect the mechanical and physical properties of the structural material. Introducing interfaces as defect traps by means of material design can effectively reduce the radiation damage of materials by separating, absorbing and annihilating irradiation-induced defects.

[0003] Metal nanofilm materials have become the focus of research in recent years because of their radiation resistance. However, existing metal nanofilm materials generally have poor electrical and mechanical properties, which makes them less resistant to radiation and unable to meet usage requirements.

[0004] Authorization announcement number CN 106350771B discloses a low thermal resistance, radiation-resistant nano multilayer film material and its preparation method, which solves the technical problem that the bimetallic nano multilayer film material containing a large number of interfaces and grain boundaries can greatly reduce the damage caused by radiation and is widely studied and recognized, but the design of this multilayer film causes a cliff-like drop in the thermal performance of the material. Therefore, in the face of high-temperature, high-irradiation nuclear reaction environment, a material that takes into account both good thermal conductivity and radiation resistance has been developed. However, it mainly solves the problem of poor thermal performance of radiation-resistant films in the prior art, and still cannot solve the problem of poor electrical and mechanical properties that are common in metal nano film materials. Summary of the invention

[0005] In view of this, an object of the present invention is to provide a method for preparing a radiation-resistant thin film material and the corresponding prepared radiation-resistant thin film material.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for preparing an anti-radiation thin film material comprises the following steps: firstly, tungsten is deposited on a substrate to form a base film by electron beam evaporation coating; then, tungsten material is deposited again on the base film to form a tungsten film by magnetron sputtering coating; and the film material having the tungsten film and the base film is sintered at 400-500°C for 50-60min to obtain the anti-radiation thin film material.

[0008] According to some preferred implementation aspects of the present invention, the electron beam evaporation coating step is: placing a tungsten film material into a crucible of an electron beam coating machine, placing a substrate on a heating furnace of the electron beam coating machine, so that the substrate is located 35-40 cm above the crucible, and performing electron beam evaporation coating;

[0009] According to some preferred implementation aspects of the present invention, the step of magnetron sputtering coating is: placing the coated substrate into a magnetron sputtering anode cover, adjusting the sputtering parameters, and then performing magnetron sputtering coating, sputtering reaction for 35-40 minutes, cooling to room temperature after sputtering, and taking out the film material.

[0010] According to some preferred implementation aspects of the present invention, an annealing treatment is included: the prepared radiation-resistant thin film material is annealed under the condition of being heated and continuously filled with oxygen.

[0011] According to some preferred implementation aspects of the present invention, the annealing process is: placing the prepared radiation-resistant thin film material into a resistance furnace; filling the resistance furnace with oxygen and exhausting it for 30 minutes; starting heating, and keeping the temperature for 2-3 hours after reaching 200-600°C, during which the oxygen flow rate is maintained at 0.3-0.6L / min.

[0012] According to some preferred embodiments of the present invention, the substrate is obtained by cutting a silicon wafer, followed by cleaning and drying.

[0013] According to some preferred embodiments of the present invention, the cleaning and drying are as follows: first, the silicon wafer is cleaned with detergent and / or ethanol for 3-4 times, and then rinsed with deionized water for 10-15 minutes until a uniform water film is formed on the silicon wafer; then, the cleaned silicon wafer is ultrasonically cleaned with deionized water and ethanol in turn, and then purged with inert gas for drying and set aside.

[0014] According to some preferred implementation aspects of the present invention, the parameters of the electron beam evaporation coating are: vacuum degree: 2.5-2.7×10 -4 Pa; evaporation rate: 20-25A / s; substrate temperature: 110-130°C; evaporation time: 20-30min; electron gun voltage: 8-10Kv; electron gun current: 0.15-0.25A. Preferably, the parameters of the electron beam evaporation coating are: vacuum degree: 2.6×10-4Pa; evaporation rate: 20-25A / s; substrate temperature: 120°C; evaporation time: 25min; electron gun voltage: 9Kv; electron gun current: 0.2A.

[0015] According to some preferred implementation aspects of the present invention, the parameters of the magnetron sputtering are: the purity of argon is 99.9%, the flow rate of argon is 35-40 sccm, the body pressure is 3.5-4.5×10 -4Pa, deposition pressure 0.1-0.3 Pa, deposition temperature 250-300 ° C, target operating current 0.2-0.5 A, target operating voltage 550-600 V, and rotating frame speed 10 r / min. Preferably, the body pressure is 4.0×10 -4 Pa, deposition pressure 0.2Pa, turntable speed 10r / min.

[0016] According to some preferred implementation aspects of the present invention, the overall thickness of the tungsten radiation-resistant thin film material is 30-500 nm.

[0017] The present invention also provides a radiation-resistant thin film material prepared according to the above preparation method.

[0018] Due to the adoption of the above technical scheme, compared with the prior art, the advantages of the present invention are as follows: the preparation method of the radiation-resistant thin film material of the present invention takes silicon as the substrate, performs two coating processes by electron beam evaporation coating and magnetron sputtering coating, and then performs sintering, annealing and other steps to finally obtain a thin film material with silicon as the substrate. A new α phase (diffraction peaks α(200), α(211), α(220)) appears in the thin film, and the β phase diffraction peak does not disappear. Therefore, coexisting phases α and β exist in the tungsten thin film material with silicon as the substrate, that is, it has relatively excellent electrical properties and excellent mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 This is a diagram showing the effect of different coating times on the metal tungsten nanofilm in an embodiment of the present invention;

[0021] Figure 2 The graph of the change of the particle size of the tungsten / Si film at different preparation temperatures of the present invention;

[0022] Figure 3 The performance diagram of tungsten / Si thin film at different preparation temperatures of the present invention;

[0023] Figure 4 This is a roughness variation diagram of the tungsten / Si film at different preparation temperatures of the present invention. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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 should fall within the scope of protection of the present invention.

[0025] The method for preparing the radiation-resistant thin film material of the present invention comprises the following steps:

[0026] S1: Cut the silicon wafer into the size required for the experiment, clean and dry it, and obtain the substrate for use.

[0027] Cleaning and Drying The cleaning process is: clean the silicon wafer 3-4 times with detergent and ethanol respectively, then rinse with deionized water for 10-15 minutes until a uniform water film is attached to the silicon wafer; ultrasonically clean the cleaned silicon wafer with deionized water and anhydrous ethanol for 30 minutes in turn, blow dry with nitrogen and set aside.

[0028] S2: Place the tungsten film material into the crucible of the electron beam coating machine, and place the cleaned and dried substrate into the heating furnace of the electron beam coating machine so that the substrate is located 35-40 cm above the crucible for electron beam evaporation coating.

[0029] The parameters of electron beam evaporation coating are: vacuum degree: 2.6×10 -4 Pa; evaporation rate: 20-25A / s; substrate temperature: 120℃; evaporation time: 25min; electron gun voltage: 9Kv; electron gun current: 0.2A.

[0030] S3: Place the coated substrate into the magnetron sputtering anode cover, adjust the sputtering parameters, and sputter for 35-40 minutes. After the sputtering is completed, cool it to room temperature and take out the film.

[0031] Electron beam coating is uniform and has high density. First, a base film is formed by electron coating, and then it is coated again by magnetron sputtering coating. Using the magnetron sputtering coating method, since the deposition current and target voltage can be controlled, that is, the sputtering power can be adjusted and controlled, the film thickness has good controllability and repeatability.

[0032] The parameters of magnetron sputtering are: Ar purity 99.9%, Ar gas flow rate 35-40sccm, body pressure 4.0×10 -4 Pa, deposition pressure 0.2Pa, deposition temperature 250-300℃, target operating current 0.2-0.5A, target operating voltage 550-600V, turntable speed 10r / min.

[0033] S4: placing the prepared film into a muffle furnace and sintering it at 400-500° C. for 50-60 min to obtain a radiation-resistant film material.

[0034] S5: annealing the radiation-resistant thin film material prepared in S4 in an annealing furnace while continuously filling it with oxygen, and finally obtaining a tungsten radiation-resistant thin film material.

[0035] The annealing process is as follows: put the prepared radiation-resistant film material into a high-temperature tubular resistance furnace; fill the resistance furnace with oxygen and exhaust it for 30 minutes; start heating, and keep it warm for 2-3 hours when the temperature reaches 200-600°C. During this process, the oxygen flow rate is maintained at 0.3-0.6L / min.

[0036] The tungsten radiation-resistant film material finally prepared is a polycrystalline metal tungsten nanofilm with a thickness of 30-500nm.

[0037] Example 1

[0038] The method for preparing the radiation-resistant thin film material of this embodiment comprises the following steps:

[0039] S1: Cut the silicon material into the size required for the experiment as a sample substrate, and clean and dry it for later use.

[0040] The cleaning process of the silicon material in S1 is as follows: the sample substrate is cleaned 3 times with detergent and ethanol respectively, and then rinsed with deionized water for 10 minutes until a uniform water film can be formed on the sample substrate; the cleaned sample substrate is ultrasonically cleaned with deionized water and anhydrous ethanol for 30 minutes in turn, and dried with nitrogen purge for later use.

[0041] S2: Place the tungsten film material into the crucible of the electron beam coating machine, and place the cleaned and dried sample substrate on the heating furnace of the electron beam coating machine so that the sample substrate is located 35 cm above the crucible.

[0042] S3: Place the sample substrate into the magnetron sputtering anode cover, adjust the sputtering parameters, and sputter for 35 minutes. After the sputtering is completed, cool to room temperature and take out the sample substrate.

[0043] The sputtering parameters in S3 are: Ar purity 99.9%, Ar gas flow rate 35 sccm, body pressure 4.0×10 -4 Pa, deposition pressure 0.2Pa, deposition temperature 250℃, target operating current 0.2A, target operating voltage 550V, and turntable speed 10r / min.

[0044] S4: The prepared film is placed in a muffle furnace and sintered at 400° C. for 50 min to obtain a tungsten radiation-resistant film.

[0045] S5: annealing the tungsten anti-radiation film prepared in S4 in an annealing furnace while continuously filling it with oxygen, and finally obtaining a tungsten anti-radiation film material.

[0046] The annealing process in S5 is as follows: first, the prepared tungsten radiation-resistant film sample is placed in a high-temperature tubular resistance furnace, and then oxygen is filled into the resistance furnace to exhaust for 30 minutes, and then it is heated until the temperature reaches 200°C and then kept warm for 2 hours. During this process, the oxygen flow rate is maintained at 0.3L / min.

[0047] In a preferred embodiment, the tungsten radiation-resistant thin film material is a polycrystalline metal tungsten nanofilm with a thickness in the range of 30-500 nm.

[0048] Example 2

[0049] The method for preparing the radiation-resistant thin film material of this embodiment comprises the following steps:

[0050] S1: Cut the silicon material into the size required for the experiment as a sample substrate, and clean and dry it for later use.

[0051] The cleaning process of the silicon material in S1 is as follows: the sample substrate is cleaned 4 times with detergent and ethanol respectively, and then rinsed with deionized water for 15 minutes until a uniform water film can be formed on the sample substrate; the cleaned sample substrate is ultrasonically cleaned with deionized water and anhydrous ethanol for 30 minutes in turn, and then purged with nitrogen for drying for later use.

[0052] S2: Place the tungsten film material into the crucible of the electron beam coating machine, and place the cleaned and dried sample substrate on the heating furnace of the electron beam coating machine so that the sample substrate is located 40 cm above the crucible.

[0053] S3: Place the sample substrate into the magnetron sputtering anode cover, adjust the sputtering parameters, and sputter for 35-40 minutes. After the sputtering is completed, cool to room temperature and take out the sample substrate.

[0054] The sputtering parameters in S3 are: Ar purity 99.9%, Ar gas flow rate 40 sccm, body pressure 4.0×10 -4 Pa, deposition pressure 0.2Pa, deposition temperature 300℃, target operating current 0.5A, target operating voltage 600V, and turntable speed 10r / min.

[0055] S4: The prepared film is placed in a muffle furnace and sintered at 500° C. for 60 minutes to obtain a tungsten radiation-resistant film.

[0056] S5: annealing the tungsten anti-radiation film prepared in S4 in an annealing furnace while continuously filling it with oxygen, and finally obtaining a tungsten anti-radiation film material.

[0057] The annealing process in S5 is as follows: first, the prepared tungsten radiation-resistant film sample is placed in a high-temperature tubular resistance furnace, and then oxygen is filled into the resistance furnace to exhaust for 30 minutes, and then it is heated until the temperature reaches 600°C and then kept warm for 3 hours. During this process, the oxygen flow rate is maintained at 0.6L / min.

[0058] The tungsten radiation-resistant film material is a polycrystalline metal tungsten nanofilm with a thickness in the range of 30-500nm.

[0059] Tests and Results

[0060] The performance of metal tungsten nanofilms under different preparation conditions was tested through experiments. The experimental results are as follows: Figure 1-4 As shown:

[0061] Figure 1 Middle: When the magnetron sputtering coating time is 15 minutes, only β phase exists in the tungsten film, and the film thickness is 322nm. Figure 1 The spectrum line in the middle and lower part; as the time increases to 40 minutes, the film thickness is 821nm; a new α phase appears in the tungsten film (diffraction peaks α(200), α(211), α(220)), and the β phase diffraction peak does not disappear. Therefore, when the coating time is 40 minutes, there are coexisting phases α and β in the tungsten film (α phase has excellent electrical properties, and β phase has excellent mechanical properties). Figure 1 The spectrum line in the upper middle.

[0062] Figure 2 Middle: From left to right and from top to bottom, the coating is 40 minutes at 30℃, 40 minutes at 250℃, 40 minutes at 300℃, and 15 minutes at 300℃. The results show that the increase in temperature leads to an increase in the size of the deposited particles; at the same temperature, the increase in time leads to an increase in the size of the particles.

[0063] Figure 3 Middle: XRD of the final product at room temperature of 30°C, with obvious α-tungsten (110), (200), (211), (220) peaks, and an abnormal peak near 70°, which should be the peak of SiO2. This shows that the crystallinity of this product is high and the product purity is high.

[0064] Figure 4 Middle: The roughness decreases first and then increases with temperature, and the roughness is the largest at 300℃. This shows that 300℃ is an appropriate and reasonable choice for magnetron coating.

[0065] From the above experimental results, it can be seen that the tungsten radiation-resistant film prepared by this method has excellent electrical and mechanical properties (because it has both α and β phases). The parameters are determined by experiments, so that the metal nanomaterial film prepared by this method has high stability, a smooth surface, and strong radiation resistance. When the coating time is 40 minutes, a new α phase (diffraction peaks α(200), α(211), α(220)) appears in the tungsten film, and the β phase diffraction peak does not disappear. Therefore, the tungsten film with silicon as the substrate has coexisting phases α and β, that is, it has excellent electrical properties and excellent mechanical properties.

[0066] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a radiation-resistant thin film material, characterized in that: The method comprises the following steps: firstly depositing tungsten on a substrate by electron beam evaporation coating to form a base film; then depositing tungsten material on the base film by magnetron sputtering coating to form a tungsten film; and sintering the film material having the tungsten film and the base film at 400-500° C. to obtain the radiation-resistant thin film material; The method comprises the following annealing steps: annealing the prepared radiation-resistant film material under heating and continuous oxygen filling; the annealing process comprises: placing the prepared radiation-resistant film material into a resistance furnace; heating the resistance furnace after oxygen is filled into the furnace and exhausting the gas, and keeping the temperature for 2-3 hours after the temperature reaches 200-600°C; and maintaining the oxygen flow rate at 0.3-0.6L / min during the annealing process; The parameters of the electron beam evaporation coating are: vacuum degree: 2.5-2.7×10 -4 Pa; evaporation rate: 20-25A / s; substrate temperature: 110-130°C; evaporation time: 20-30min; electron gun voltage: 8-10Kv; electron gun current: 0.15-0.25A; and / or, the parameters of the magnetron sputtering coating are: the flow value of argon gas is 35-40sccm, the body pressure is 3.5-4.5×10 -4 Pa, deposition pressure 0.1-0.3Pa, deposition temperature 250-300℃, target operating current 0.2-0.5A, target operating voltage 550-600V.

2. The preparation method according to claim 1, characterized in that: The steps of electron beam evaporation coating are as follows: placing tungsten film material into the crucible of the electron beam coating machine, placing the substrate on the heating furnace of the electron beam coating machine, making the substrate 35-40 cm above the crucible, and performing electron beam evaporation coating to form a base film on the substrate.

3. The preparation method according to claim 1, characterized in that: The steps of the magnetron sputtering coating are as follows: placing the substrate with the base film formed on the surface into a magnetron sputtering anode cover, performing magnetron sputtering coating, sputtering reaction for 35-40 minutes, cooling to room temperature after the sputtering is completed, and taking out the film material.

4. The preparation method according to claim 1, characterized in that: The substrate is obtained by cutting a silicon wafer, cleaning it and drying it.

5. The preparation method according to claim 4, characterized in that: The cleaning and drying are as follows: first, the silicon wafer is cleaned with detergent and / or ethanol, and then rinsed with deionized water until a uniform water film is formed on the silicon wafer; then, the cleaned silicon wafer is ultrasonically cleaned with deionized water and ethanol in turn, and then purged with inert gas for drying and then used for later use.

6. The preparation method according to claim 1, characterized in that: The overall thickness of the radiation-resistant thin film material is 30-500 nm.

7. A radiation-resistant thin film material prepared according to the preparation method according to any one of claims 1 to 6.

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