CN111304602B - Superhydrophobic diamond-like composite layer structure and its preparation method - Google Patents

Abstract

The invention provides a method for preparing a diamond composite layer structure, comprising the following steps: providing a substrate, performing pretreatment, glow cleaning, and ion etching cleaning on the substrate in sequence; placing the cleaned substrate in a deposition chamber, feeding argon gas, adjusting the pressure of the vacuum chamber to 0.2-1.3Pa, turning on the first target and the second target, and controlling the target power of the first target to 30-70W, controlling the target power of the second target to 30-70W, and the substrate bias to 100-30 Under the condition of 0V, a prefabricated transition layer is deposited; the sample deposited with the prefabricated transition layer is taken out, placed in a container containing an etching solution, and subjected to ultrasonic treatment, and the prefabricated transition layer is etched to form a transition layer with a micro-nano structure array on the surface, and an etching sample is obtained; after the surface of the etching sample is cleaned, it is placed in a deposition chamber, and a diamond-like carbon layer is deposited on the surface of the transition layer of the etching sample.

Description

Superhydrophobic diamond-like composite layer structure and its preparation method

technical field

The invention belongs to the technical field of diamond-like coatings, and in particular relates to a superhydrophobic diamond-like composite layer structure and a preparation method thereof.

Background technique

In recent years, superhydrophobic materials with special wetting properties have attracted widespread attention. Superhydrophobic materials have extremely broad application prospects in medical biology, industrial and agricultural production, and daily life, such as self-cleaning materials, oil-water separation materials, anti-fouling fabrics, and drag-reducing materials. However, the superhydrophobic materials currently researched are complex in preparation process and high in cost, and the hardness of the prepared superhydrophobic materials is not high, which cannot meet the requirements of diversified materials. Therefore, the method of developing a high-hardness, super-hydrophobic material has an important role and significance in promoting the wide application of materials with special wetting properties.

Diamond-like carbon (DLC) is an amorphous carbon material with sp ² and sp ³ bonding characteristics. Due to its high hardness and high elastic modulus, low friction coefficient, wear resistance and good vacuum tribological properties, it is very suitable as a wear-resistant coating, which has attracted the attention of the tribology community. It has broad application prospects in the fields of cutting tools, molds, parts and biomedical devices. However, the lack of hydrophobicity greatly limits the industrial application of diamond coatings.

Contents of the invention

The purpose of the present invention is to provide a super-hydrophobic diamond-like composite layer structure and a preparation method thereof, aiming at solving the problem that the existing diamond-like coatings do not possess hydrophobicity.

For realizing above-mentioned purpose of the invention, the technical scheme that the present invention adopts is as follows:

One aspect of the present invention provides a diamond-like composite layer structure, the diamond-like composite layer structure includes a substrate, a transition layer disposed on the surface of the substrate, and a diamond-like layer disposed on the surface of the transition layer away from the substrate, wherein,

The transition layer protrudes on the side away from the base to form a micro-nano array structure, and the surface of the diamond-like layer away from the base is a micro-nano array surface.

Preferably, in the transition layer, the height of the micro-nano array structure is 0.5-2 microns, and the distance between adjacent micro-nano units in the micro-nano array structure is 0.1-2 microns.

Preferably, on the surface of the micro-nano array of the diamond-like carbon layer, the height of the micro-nano array is 0.5-2 microns, and the distance between adjacent micro-nano units in the micro-nano array is 0.1-2 microns.

Preferably, the transition layer is selected from a metal layer or a non-metal layer, wherein,

The metal layer is one of iron layer, aluminum layer, copper layer, silver layer, tin layer, titanium layer, germanium layer,

The non-metallic layer is one of carbon layer, silicon layer and organic polymer layer.

Preferably, the substrate is selected from one of carbon steel substrates, stainless steel substrates, high-grade steel substrates, cemented carbide substrates, and ceramic substrates.

Another aspect of the present invention provides a method for preparing a diamond-like composite layer structure, comprising the following steps:

providing a substrate, and sequentially performing pretreatment, glow cleaning and ion etching cleaning on the substrate;

placing the cleaned substrate in a deposition chamber, feeding in argon, adjusting the pressure of the vacuum chamber to 0.2-1.3 Pa, turning on the first target and the second target, controlling the target power of the first target to be 30-70W, controlling the target power of the second target to be 30-70W, and depositing a prefabricated transition layer under the condition that the bias voltage of the substrate is 100-300V;

Taking out the sample deposited with the prefabricated transition layer, placing it in a container containing an etching solution, performing ultrasonic treatment, performing etching treatment on the prefabricated transition layer, forming a transition layer with a micro-nano structure array on the surface, and obtaining an etched sample;

After the etched sample is subjected to surface cleaning treatment, it is placed in a deposition chamber, and a diamond-like carbon layer is deposited on the surface of the transition layer of the etched sample;

Wherein, the first target and the second target are independently selected from metal or non-metallic materials, and the first target is selected from targets soluble in the etching solution, and the second target is selected from targets insoluble in the etching solution; or

The first target is selected from metal or non-metal targets, the second target is selected from metal or non-metal targets, and the etchant is an etchant that can dissolve the first target but not the second target.

Preferably, the first target material and the second target material are selected from metal materials, and the metal materials include iron, aluminum, copper, silver, tin, titanium, and germanium.

Preferably, the first target material and the second target material are selected from non-metallic materials, and the non-metallic materials include carbon, silicon, and organic polymers.

Preferably, the first target is selected from metallic materials, the second target is selected from non-metallic materials, or the first target is selected from non-metallic materials, and the second target is selected from metallic materials,

Wherein, the metal material is selected from iron, aluminum, copper, silver, tin, titanium, germanium, and the non-metallic material is selected from carbon, silicon, and organic polymer.

Preferably, the etching solution is selected from acidic solutions, and the acidic solution is selected from at least one of nitric acid, sulfuric acid, hydrochloric acid, hydrofluoric acid, and organic acids.

Preferably, the etching solution is selected from alkaline solutions, and the alkaline solution is selected from at least one of sodium hydroxide, potassium hydroxide, calcium hydroxide, lithium hydroxide, and organic bases.

Preferably, in the step of depositing a diamond-like carbon layer on the surface of the transition layer of the etched sample, the etched sample is cleaned and placed in a deposition chamber, using acetylene as a working gas, and the pressure in the vacuum chamber is adjusted to 0.5-1.0 Pa, the ion source voltage is 50-100V, and the substrate bias is 50-200V, and the diamond-like carbon layer is deposited on the transition layer surface of the etched sample.

In the diamond-like composite layer structure provided by the present invention, a transition layer with a micro-nano array structure is arranged on the surface of the substrate, and further, a diamond-like layer with a micro-nano array surface is formed on the surface of the transition layer. The resulting diamond-like composite layer structure uses diamond-like carbon as a material basis, so it has the advantage of high hardness. At the same time, since the diamond-like layer has a micro-nano array surface, the diamond-like composite layer structure is endowed with excellent hydrophobic properties. The contact angle experiment shows that the contact angle (surface of the diamond-like layer) of the diamond-like composite layer structure is 153° to 155°. In summary, the diamond-like composite layer structure not only has high hardness, but also has excellent hydrophobic properties, and can be used as a wetting material that requires high hardness and hydrophobic properties, thereby expanding the industrial application prospects of diamond-like carbon.

The preparation method of the diamond-like composite layer structure provided by the present invention adopts the combination of ion source and arc ion plating, and prepares the diamond-like superhydrophobic composite structure layer through deposition and etching process. On the one hand, by preparing the transition layer, the method can realize the firm bonding of the diamond-like carbon layer on the substrate, improve the adhesion of the diamond-like carbon layer on the substrate, and prevent the peeling off of the diamond-like carbon coating; on the other hand, the transition layer is etched, and the transition layer forms a micro-nano array structure, which provides a structural basis for the deposition of diamond-like carbon, and finally obtains a diamond-like carbon layer with a micro-nano array on the surface, realizing the super-hydrophobic function of the diamond-like carbon layer.

Description of drawings

Fig. 1 is the structural representation of the diamond-like composite layer structure that the embodiment of the present invention provides;

2 is a schematic diagram of an ion source coating device provided by an embodiment of the present invention;

Fig. 3 is the contact angle test result figure of the diamond-like composite layer structure that the embodiment of the present invention 1 provides;

Fig. 4 is a graph showing the contact angle test results of the diamond-like composite layer structure provided by Example 2 of the present invention.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention will be further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

In the description of the present invention, it should be understood that the terms "first" and "second" are used for description purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

Due to its excellent properties, especially high hardness and good scratch resistance, diamond-like coatings have been increasingly used in various industries, from machinery manufacturing to optoelectronics, from medicine to aerospace. However, it is precisely because of the material properties of the diamond-like material itself that the diamond-like material does not have hydrophobic properties, and it is difficult to be used in technologies that require better hydrophobic properties. In view of this, the present invention aims to provide a method for preparing a diamond-like composite layer structure with high hardness and superhydrophobic ability, and a corresponding diamond-like composite layer structure with high hardness and superhydrophobic ability.

1, an embodiment of the present invention provides a diamond-like composite layer structure, which includes a substrate 10, a transition layer 20 disposed on the surface of the substrate 10, and a diamond-like layer 30 disposed on the surface of the transition layer 20 away from the substrate 10, wherein,

The transition layer 20 protrudes on the side facing away from the substrate 10 to form a micro-nano array structure, and the surface of the diamond-like carbon layer 30 facing away from the substrate 10 is the surface of the micro-nano array.

The diamond-like composite layer structure includes a three-layer structure, specifically, including a substrate 10 , a diamond-like carbon layer 30 , and a transition layer 20 disposed between the substrate 10 and the diamond-like carbon layer 30 . Each layer is described in detail below.

base 10

In the embodiment of the present invention, the substrate 10 is used as the bearing layer of the diamond-like composite layer structure, and theoretically, a material with a certain hardness can be selected. Considering that the micro-nano array structure of the transition layer 20 is preferably formed by an etching method, the material of the substrate 10 is preferably selected from a material with strong stability. Wherein, the strong stability means that it has good stability in conventional acidic etching solution or alkaline etching solution, and will not be etched by acid or alkali.

In the embodiment of the present invention, at least one surface of the substrate 10 is a flat surface, so as to form a regular transition layer 20 and a diamond-like carbon layer 30 on the surface. In some embodiments, the substrate 10 is selected from one of a carbon steel substrate 10 , a stainless steel substrate 10 , a high-grade steel substrate 10 , a cemented carbide substrate 10 , and a ceramic substrate 10 , but is not limited thereto. Carbon steel substrate 10, stainless steel substrate 10, high-quality steel substrate 10, cemented carbide substrate 10, and ceramic substrate 10 not only have good hardness, but also have good stability, and can be applied to prepare transition layer 20 and diamond-like layer 30 under various conditions. Specifically, the type of the substrate 10 can be adjusted according to the actual preparation conditions of the transition layer 20 and the diamond-like carbon layer 30 , such as the type of etchant.

The thickness of the substrate 10 is 0.5 micrometers to 26 micrometers, specifically, it can be adjusted according to the thicknesses of the transition layer 20 and the diamond-like carbon layer 30 . When the transition layer 20 and the DLC layer 30 to be deposited are thin, the thickness of the substrate 10 is relatively thin; when the transition layer 20 and the DLC layer 30 to be deposited are thick, the thickness of the substrate 10 is relatively thick. Overall, the thickness of the diamond-like composite layer structure is 1.5 microns to 30 microns, which has good general adaptability.

transition layer 20

In the embodiment of the present invention, the transition layer 20 is combined on the substrate 10 and combined with the diamond-like carbon layer 30 at the same time. On the one hand, the transition layer 20 is arranged between the substrate 10 and the diamond-like carbon layer 30 to form a material transition between the substrate 10 and the diamond-like carbon layer 30, improve the bonding ability of the diamond-like carbon layer 30 on the substrate 10, and prevent the diamond-like carbon layer 30 from falling off when it is directly deposited on the substrate 10. On the other hand, since the diamond-like carbon layer 30 itself is difficult to form a micro-nano structure by etching, the structural modification of the transition layer 20 can provide a structural basis for the diamond-like carbon layer 30 to form a micro-nano array surface.

In the embodiment of the present invention, the transition layer 20 protrudes on the side away from the substrate 10 to form a micro-nano array structure, and the arrangement form is relatively flexible, as long as it can provide a structural basis for the diamond-like layer 30 to form a micro-nano array surface.

In some embodiments, the transition layer 20 between the substrate 10 and the diamond-like layer 30 may be a structural layer that completely covers the surface of the substrate 10 and protrudes to form a micro-nano array on the surface away from the substrate. At this time, since the transition layer 20 completely covers the substrate 10 and isolates the direct contact between the diamond-like carbon layer 30 and the substrate 10, the bonding of the diamond layer on the substrate 10 is stronger.

In some embodiments, the transition layer 20 between the substrate 10 and the diamond-like layer 30 is formed by the micro-nano array structure itself formed on the surface of the substrate 10, and the micro-nano structural units constituting the micro-nano array structure are not completely in contact with each other, and can even be arranged regularly without contact with each other. Correspondingly, the diamond-like carbon layer 30 fills the gaps between the micro-nano structural units between the transition layers 20, and realizes contact with the substrate in some regions. Of course, as a preferred embodiment, in the micro-nano array structure in the transition layer 20, the micro-nano structural units are regularly arranged and do not contact each other, so that when the diamond-like carbon layer 30 is subsequently formed, it can be ensured that the obtained micro-nano array surface also has better regularity and uniformity.

In the micro-nano array structure of the transition layer 20 , the shape of the micro-nano units is not strictly limited, and may be pyramidal, semicircular, columnar, cylindrical, but not limited thereto.

The transition layer 20 has a thickness of 0.5 microns to 2 microns. This thickness range is not only sufficient to improve the adhesion of the diamond-like carbon layer 30 on the substrate 10, but also has no significant impact on the overall hardness of the diamond-like carbon composite layer structure. In addition, more importantly, the micro-nano array structure formed in this thickness range can endow the diamond-like carbon layer 30 with excellent super-hydrophobic properties after being replicated by the diamond-like carbon layer 30 .

In some embodiments, the height of the micro-nano array structure in the transition layer 20 is 0.5-2 microns, and the distance between adjacent micro-nano units in the micro-nano array structure is 0.1-2 microns. At this time, the micro-nano array structure in the transition layer 20 serves as the structural basis of the diamond-like layer 30 and is replicated by the diamond-like layer 30. The formed diamond-like layer 30 also has the structural characteristics of "the height of the micro-nano array is 0.5 microns to 2 microns, and the distance between adjacent micro-nano units in the micro-nano array is 0.1 microns to 2 microns", thereby endowing the diamond-like carbon layer 30 with excellent super-hydrophobic properties, thereby providing materials with excellent hardness and super-hydrophobic properties.

In a preferred embodiment, in the micro-nano array structure, the ratio of the height of the micro-nano unit to the distance between adjacent micro-nano units is 1: (0.5-1.5). At this time, the micro-nano array structure in the transition layer 20 is used as the structural basis of the diamond-like layer 30, and is replicated by the diamond-like layer 30. The formed diamond-like layer 30 has more excellent super-hydrophobic properties, and the contact angle is between 154.2° and 155°. 10. The bonding force between the transition layer 20 and the DLC layer 30 is greater than the bonding force between the substrate 10 and the DLC layer 30 . However, the material type of the transition layer 20 is not strictly limited, and may be selected from metal layers or non-metal layers.

In some embodiments, the transition layer 20 is a metal layer, and the metal layer is one of iron layer, aluminum layer, copper layer, silver layer, tin layer, titanium layer, gold layer, platinum layer, tantalum layer, tungsten layer, vanadium layer, niobium layer, cobalt layer, nickel layer, germanium layer, but not limited thereto. The above-mentioned preferred metal layer has better bonding force with both the substrate 10 and the DLC layer 30, thereby improving the adhesion of the DLC layer 30 on the substrate 10 and improving the stability of the composite structure layer.

In some embodiments, the transition layer 20 is a non-metal layer, and the non-metal layer is one of a carbon layer, a silicon layer, a sulfur layer, a selenium layer, a tellurium layer, and an organic polymer layer, but not limited thereto. The above-mentioned preferred metal layer has better bonding force with both the substrate 10 and the DLC layer 30, thereby improving the adhesion of the DLC layer 30 on the substrate 10 and improving the stability of the composite structure layer. Specifically, the organic polymer can be selected from polytetrafluoroethylene, polyethylene, polystyrene, polyvinyl chloride, polyethylene terephthalate, polyacrylonitrile, natural rubber, styrene-butadiene rubber, butadiene rubber, polyurethane, but not limited thereto, preferably polytetrafluoroethylene, which has stable chemical properties and is not easily oxidized, and has a simple synthesis process and low cost.

DLC layer 30

In the embodiment of the present invention, the diamond-like carbon layer 30 is disposed on the surface of the transition layer 20 facing away from the substrate 10, and the surface of the diamond-like carbon layer 30 facing away from the substrate 10 is a micro-nano array surface, thereby endowing the diamond-like carbon layer 30 with excellent superhydrophobic properties.

The thickness of the diamond-like carbon layer 30 is 0.5 micrometers to 2 micrometers. This thickness range has good general adaptability and can basically meet the industry requirements for using diamond-like carbon coatings. In addition, this thickness range can be prepared by deposition, so as to ensure that the obtained diamond-like carbon coatings have good quality.

In some embodiments, on the surface of the micro-nano array of the diamond-like carbon layer 30 , the height of the micro-nano array is 0.5-2 microns, and the distance between adjacent micro-nano units in the micro-nano array is 0.1-2 microns. At this time, the diamond-like carbon layer 30 has a better surface structure, thus having excellent super-hydrophobic properties.

In a preferred embodiment, in the micro-nano array structure of the diamond-like layer 30, the ratio of the height of the micro-nano unit to the distance between adjacent micro-nano units is 1: (0.5-1.5), and the diamond-like layer 30 has more excellent superhydrophobic properties at this time, and the contact angle is between 154.2° and 155°.

As the most preferred embodiment, the diamond-like composite layer structure is composed of a substrate 10, a transition layer 20 and a diamond-like layer 30, the transition layer 20 is arranged on the surface of the substrate 10, and the diamond-like layer 30 is arranged on the surface of the transition layer 20 facing away from the substrate 10, wherein the transition layer 20 protrudes on the side away from the substrate 10 to form a micro-nano array structure, and the surface of the diamond-like layer 30 facing away from the substrate 10 is a micro-nano array surface.

In the diamond-like composite layer structure provided by the embodiment of the present invention, a transition layer 20 with a micro-nano array structure is provided on the surface of the substrate, and further, a diamond-like layer 30 with a micro-nano array surface is formed on the surface of the transition layer 20 . The resulting diamond-like composite layer structure uses diamond-like carbon as a material basis, so it has the advantage of high hardness. Simultaneously, because described diamond-like carbon layer 30 has micro-nano array surface, thereby endows described diamond-like composite layer structure with excellent hydrophobic performance, the contact angle experiment shows that the contact angle of described diamond-like composite layer structure (surface of diamond-like layer 30) is 153 ° to 155 °. In summary, the diamond-like composite layer structure not only has high hardness, but also has excellent hydrophobic properties, and can be used as a wetting material that requires high hardness and hydrophobic properties, thereby expanding the industrial application prospects of diamond-like carbon.

The diamond-like composite layer structure provided in the embodiments of the present invention can be prepared by the following method.

Another aspect of the embodiments of the present invention provides a method for preparing a diamond-like composite layer structure, comprising the following steps:

S01. Provide a substrate, and sequentially perform pretreatment, glow cleaning and ion etching cleaning on the substrate;

S02. Place the cleaned substrate in the deposition chamber, pass in argon gas, adjust the pressure of the vacuum chamber to 0.2-1.3 Pa, turn on the first target and the second target, and control the target power of the first target to 30-70W, control the target power of the second target to 30-70W, and deposit a prefabricated transition layer under the condition that the bias voltage of the substrate is 100-300V;

S03. Taking out the sample deposited with the prefabricated transition layer, placing it in a container containing an etching solution, performing ultrasonic treatment, performing etching treatment on the prefabricated transition layer, forming a transition layer with a micro-nano structure array on the surface, and obtaining an etching sample;

S04. After the etched sample is subjected to surface cleaning treatment, it is placed in a deposition chamber, and a diamond-like carbon layer is deposited on the surface of the transition layer of the etched sample;

Wherein, the first target and the second target are independently selected from metal or non-metallic materials, and the first target is selected from targets soluble in the etching solution, and the second target is selected from targets insoluble in the etching solution; or

The first target is selected from metal or non-metal targets, the second target is selected from metal or non-metal targets, and the etchant is an etchant that can dissolve the first target but not the second target.

The preparation method of the diamond-like composite layer structure provided by the embodiment of the present invention adopts the combination of ion source and arc ion plating, and prepares the diamond-like superhydrophobic composite structure layer by deposition and etching process. On the one hand, by preparing the transition layer, the method can realize the firm bonding of the diamond-like carbon layer on the substrate, improve the adhesion of the diamond-like carbon layer on the substrate, and prevent the peeling off of the diamond-like carbon coating; on the other hand, the transition layer is etched, and the transition layer forms a micro-nano array structure, which provides a structural basis for the deposition of diamond-like carbon, and finally obtains a diamond-like carbon layer with a micro-nano array on the surface, realizing the super-hydrophobic function of the diamond-like carbon layer.

Specifically, in the above step S01, the selection of the substrate is as described above. In a specific embodiment, the substrate can be selected from one of carbon steel substrates, stainless steel substrates, high-grade steel substrates, cemented carbide substrates, and ceramic substrates.

Perform pretreatment, glow cleaning and ion etching cleaning on the provided substrate in sequence, remove organic matter on the surface of the substrate through pretreatment, especially oil stains; remove substrate surface irregularities such as residual moisture and gas in scratches by glow cleaning and ion etching cleaning, so as to improve the adhesion effect of the coating. By cleaning step by step, the best cleaning effect is achieved, and the coating has the best bonding force on the cleaned substrate.

In some embodiments, the method for pretreating the substrate is: sequentially using distilled water, acetone, and absolute ethanol to ultrasonically clean the substrate to fully remove organic matter, especially oil stains, on the surface of the substrate, and then dry it.

In a specific embodiment, the substrate is ultrasonically cleaned in distilled water for 5-30 minutes, then the substrate is ultrasonically cleaned in an acetone solution for 5-30 minutes, and then the substrate is ultrasonically cleaned in absolute ethanol solution for 5-30 minutes; after cleaning, the surface of the substrate is blown dry with dry nitrogen, and finally the sample is dried in a blast drying oven at 80-150°C.

After the substrate is pretreated, glow cleaning is further performed. In some embodiments, the substrate is glow cleaned with pure argon.

Before glow cleaning, adjust the equipment parameters, specifically, fix the dried substrate on the turntable in the ion source coating equipment; close the door of the vacuum chamber, open the water cooler to connect the ion source, multi-arc target, molecular pump, and vacuum chamber waterway, turn on the air compressor and the total power supply of the composite coating machine, and then turn on the mechanical pump, side pumping valve and molecular pump, so that the molecular pump enters a climbing state; After the pressure reaches below 10Pa, open the side pumping valve again; when the pressure of the vacuum chamber reaches below 3Pa, close the rough pumping valve and open the high valve to pump a high vacuum to the vacuum chamber. When the pressure of the vacuum chamber reaches 5.0×10 ^-3 Pa, turn on the heating power to heat and bake the vacuum chamber. The heating temperature is 100-500°C. During the heating process, turn on the turret system to make the samples self-transfer; when the vacuum reaches 3.0×10 ^-3 Pa, start the glow cleaning.

In a specific embodiment, the glow cleaning method is as follows: after the glow cleaning is completed, open the main valve of the argon cylinder, the pressure reducing valve, the ion source valve, the arc valve, the target valve, and the mass flow meter, feed argon gas into the vacuum chamber, control the flow rate of the argon gas to 300-500 sccm, the working pressure is 1.0-1.7Pa, the substrate bias voltage is -500--800V, and the substrate is glow-cleaned for 10-30 minutes. Performing glow cleaning under the above conditions can quickly remove the moisture and gas trapped in the uneven surface of the substrate, especially the scratches, and prevent the adhesion of the film layer from being insufficient when the prefabricated transition layer is subsequently deposited through the combination of ion source and arc ion plating, and improve the bonding force of the film layer on the substrate.

In order to further ensure that the uneven surface of the substrate, especially the moisture and gas in the scratches are fully removed, after the glow cleaning is completed, the substrate is cleaned by ion etching, and the uneven surface of the substrate, especially the moisture and gas in the scratches, is completely removed in a relatively soft way.

In some specific embodiments, the ion etching cleaning method is: after the etching cleaning is completed, turn on the ion source to perform ion bombardment cleaning on the sample, wherein the ion source voltage is 50-90V, the argon gas flow rate is 70-500 sccm, the working pressure is 0.5-1.7Pa, and the substrate bias voltage is 100-800V. Under the above conditions, the moisture and gas that were not removed during the glow cleaning process can be completely removed. Preferably, the cleaning time of the ion bombardment cleaning is 10-30 minutes.

In the embodiment of the present invention, by sequentially performing pretreatment, glow cleaning and ion etching cleaning on the substrate, various attachments on the surface of the substrate can be removed step by step and with different strengths, and the adhesion of the coating on the surface of the substrate can be improved; at the same time, the surface cleaning of the substrate according to this method also has good timeliness.

In the above step S02, the combination of ion source and arc ion plating is used to deposit a prefabricated transition layer on the surface of the substrate. Here, the combination of the two coating methods can improve the bonding force and surface regularity of the coating. In the embodiment of the present invention, the prefabricated transition layer is used as the material basis of the transition layer in the diamond-like composite layer structure, and after the etching treatment in the following steps, the transition layer of the diamond-like composite layer structure is finally formed.

In the embodiment of the present invention, the cleaned substrate is placed in the deposition chamber of the ion source coating equipment. The ion source coating equipment is shown in FIG. 2 . Argon gas is introduced into the deposition chamber, the pressure of the vacuum chamber is adjusted to 0.2-1.3 Pa, the first target and the second target are turned on, and the target power of the first target is controlled to be 30-70W, the target power of the second target is controlled to be 30-70W, and the prefabricated transition layer is deposited under the condition that the substrate bias is 100-300V.

In the step of preparing the prefabricated transition layer, the pressure of the vacuum chamber, the target power of the first target material, the target power of the second target material and the substrate bias jointly determine the quality of the prefabricated transition layer. If any one of the vacuum chamber pressure, target power, and substrate bias voltage becomes smaller, the deposition rate is too slow and the deposition time is too long; and if any one of the vacuum chamber pressure, target power, and substrate bias voltage is too high, the deposition speed is too fast, and the grains formed when the two targets are mixed-plated are too large and arranged irregularly, which will reduce the binding force of the prefabricated transition layer on the substrate. Moreover, the pressure of the vacuum chamber, the target power of the first target, the target power of the second target, and the substrate bias are interrelated, and changes in any parameter may lead to changes in the deposition effect. In the method for prefabricating the transition layer provided in the embodiments of the present invention, the pressure of the vacuum chamber, the target power of the first target, the target power of the second target, and the substrate bias are within the above ranges, so that the grain size in the obtained prefabricated transition layer is suitable, and the binding force of the prefabricated transition layer on the surface of the substrate is enhanced.

Further preferably, the flow rate of the argon gas is 50-400 sccm, so as to provide a suitable vacuum chamber pressure.

In the step of preparing the prefabricated transition layer in the embodiment of the present invention, in order to form the transition layer with micro-nano structure arrays on the surface, double targets are used to prepare the prefabricated transition layer. The two targets together serve as the material basis of the prefabricated transition layer, and are uniformly deposited by mixed plating to form a prefabricated transition layer, and wherein the first target is used as a sacrificial material, which is removed by etching with an etching solution in the following steps, and finally, the prefabricated transition layer becomes a transition layer with an array of micro-nano structures.

This means that the material selection of the first target and the second target in the embodiment of the present invention is closely related to the type of etchant in the following steps, in addition to the second target needing to meet the material requirements of the transition layer in the diamond-like composite layer structure. Specifically, the first target and the second target are independently selected from metal or non-metallic materials, and the first target is selected from targets soluble in the etching solution, and the second target is selected from targets insoluble in the etching solution. It can also be understood that the first target is selected from targets of metal or non-metal materials, the second target is selected from targets of metal or non-metal materials, and the etching solution is an etching solution that can dissolve the first target but cannot dissolve the second target.

On the premise of meeting the above basic requirements, in some embodiments, the first target and the second target are selected from metal materials, and the metal materials include iron, aluminum, copper, silver, tin, titanium, germanium, gold, platinum, tantalum, tungsten, vanadium, niobium, cobalt, and nickel.

In some embodiments, the first target material and the second target material are selected from non-metallic materials, and the non-metallic materials include carbon, silicon, sulfur, selenium, tellurium, and organic polymers.

In some embodiments, the first target is selected from metal materials, the second target is selected from non-metal materials, wherein the metal materials are selected from iron, aluminum, copper, silver, tin, titanium, germanium, gold, platinum, tantalum, tungsten, vanadium, niobium, cobalt, nickel, and the non-metal materials are selected from carbon, silicon, sulfur, selenium, tellurium, and organic polymers.

In some embodiments, the first target is selected from non-metallic materials, the second target is selected from metallic materials, wherein the metallic materials are selected from iron, aluminum, copper, silver, tin, titanium, germanium, gold, platinum, tantalum, tungsten, vanadium, niobium, cobalt, nickel, and the non-metallic materials are selected from carbon, silicon, and organic polymers.

It can be understood that, as long as the selected etchant matches, the second target material can be selected from various materials listed above, that is, the transition layer is selected from a metal layer or a non-metal layer, wherein the metal layer is one of iron layer, aluminum layer, copper layer, silver layer, tin layer, titanium layer, gold layer, platinum layer, tantalum layer, tungsten layer, vanadium layer, niobium layer, cobalt layer, nickel layer, germanium layer, and the non-metal layer is one of carbon layer, silicon layer, sulfur layer, selenium layer, tellurium layer, and organic polymer layer.

The advantages of the above-mentioned preferred target materials are as described above, and will not be repeated here. Wherein, the organic polymer can be selected from polytetrafluoroethylene, polyethylene, polystyrene, polyvinyl chloride, polyethylene terephthalate, polyacrylonitrile, natural rubber, styrene-butadiene rubber, butadiene rubber, polyurethane, but not limited thereto, preferably polytetrafluoroethylene.

Further, after the deposition is completed, turn off the ion source power supply and the bias power supply, and then close the gas mass flowmeter, the main valve of the gas cylinder and the pressure reducing valve; set the cooling program, and when the temperature drops below 100°C, close the high valve, open the vent valve, and open the vacuum chamber door when the pressure in the vacuum chamber is consistent with the external air pressure.

In the above step S03, the sample deposited with the prefabricated transition layer is taken out, placed in a container containing an etching solution, and subjected to ultrasonic treatment to etch the prefabricated transition layer. The selection of the etching solution only needs to be able to dissolve the first target but not dissolve the second target, and there is no other requirement.

In some embodiments, the etching solution is selected from acidic solutions, and the acidic solution is selected from at least one of nitric acid, sulfuric acid, hydrochloric acid, hydrofluoric acid, and organic acids. At this time, the first target material corresponds to a target material that can be dissolved by the acidic solution, and the second target material corresponds to not being affected by the acidic etching solution, that is, not being affected by the acidic solution.

In some embodiments, the etching solution is selected from an alkaline solution, and the alkaline solution is selected from at least one of sodium hydroxide, potassium hydroxide, calcium hydroxide, lithium hydroxide, and an organic base. At this time, the first target material corresponds to a target material that can be dissolved by the alkaline solution, and the second target material corresponds to not being affected by the acidic etching solution, that is, not being affected by the alkaline solution.

After etching treatment, the prefabricated transition layer forms a transition layer with a micro-nano structure array on the surface. In the embodiment of the present invention, the fine structure of the micro-nano array can be further controlled by adjusting the etching conditions, such as temperature and concentration of etching solution. Preferably, in the transition layer, the height of the micro-nano array structure is 0.5-2 microns, and the distance between adjacent micro-nano units in the micro-nano array structure is 0.1-2 microns.

In the above step S04, the etched sample is subjected to surface cleaning treatment, and the surface cleaning treatment can be realized by the above-mentioned pretreatment and glow cleaning treatment. Further, it is preferable to use ion etching to clean after the glow cleaning.

The cleaned etching sample is placed in a deposition chamber, and a diamond-like carbon layer is deposited on the surface of the transition layer of the etching sample to form a surface having the same structure as the transition layer. Preferably, in the step of depositing a diamond-like carbon layer on the surface of the transition layer of the etched sample, the etched sample is cleaned and placed in a deposition chamber, using acetylene as a working gas, and the pressure in the vacuum chamber is adjusted to 0.5-1.0 Pa, the ion source voltage is 50-100V, and the substrate bias is 50-200V, and the diamond-like carbon layer is deposited on the transition layer surface of the etched sample.

In the step of preparing the diamond-like carbon layer, the pressure of the vacuum chamber, the voltage of the ion source and the bias voltage of the substrate jointly determine the quality of the diamond-like carbon layer. If any one of the vacuum chamber pressure, ion source voltage and substrate bias voltage becomes smaller, the deposition rate is too slow and the deposition time is too long; and if any one of the vacuum chamber pressure, ion source voltage and substrate bias voltage is too high, the deposition rate is too fast, and the formed crystal grains are arranged irregularly, thereby reducing the binding force of the diamond-like carbon layer in the transition layer. Moreover, the pressure of the vacuum chamber, the voltage of the ion source and the bias voltage of the substrate are interrelated, and any change in any parameter may lead to a change in the deposition effect. The parameter conditions of the transition layer provided by the embodiments of the present invention can enhance the binding force of the diamond-like carbon layer obtained, and form a dense and uniform coating.

After the coating deposition is completed, turn off the ion source power supply and bias power supply, and then close the gas mass flowmeter, gas cylinder main valve and pressure reducing valve; set the cooling program, and when the temperature drops below 100°C, close the high valve and open the vent valve. When the pressure in the vacuum chamber is consistent with the external pressure, open the vacuum chamber door, and then take out the sample.

Preferably, on the surface of the micro-nano array of the diamond-like carbon layer, the height of the micro-nano array is 0.5 micron to 2 microns, and the distance between adjacent micro-nano units in the micro-nano array is 0.1 micron to 2 microns, and the resulting diamond-like layer has better superhydrophobic properties.

The following will be described in conjunction with specific embodiments.

Example 1

A preparation method of a diamond-like composite layer structure, comprising the following steps:

S11. Provide a substrate, and sequentially perform pretreatment, glow cleaning and ion etching cleaning on the substrate; specifically:

Put the substrate in distilled water for ultrasonic cleaning for 5-30 minutes, then put the substrate in acetone solution for ultrasonic cleaning for 5-30 minutes, and then put the substrate in absolute ethanol solution for ultrasonic cleaning for 5-30 minutes; after cleaning, dry the surface of the substrate with dry nitrogen, and finally put the sample in a blast drying oven at 80-150°C for drying. Before glow cleaning, adjust the equipment parameters, specifically, fix the dried substrate on the turntable in the ion source coating equipment; close the door of the vacuum chamber, open the water cooler to connect the ion source, multi-arc target, molecular pump, and vacuum chamber waterway, turn on the air compressor and the total power supply of the composite coating machine, and then turn on the mechanical pump, side pumping valve and molecular pump, so that the molecular pump enters a climbing state; After the pressure reaches below 10Pa, open the side pumping valve again; when the pressure of the vacuum chamber reaches below 3Pa, close the rough pumping valve and open the high valve to pump a high vacuum to the vacuum chamber. When the pressure of the vacuum chamber reaches 5.0×10 ^-3 Pa, turn on the heating power to heat and bake the vacuum chamber. The heating temperature is 100-500°C. During the heating process, turn on the turret system to make the samples self-transfer; when the vacuum reaches 3.0×10 ^-3 Pa, start the glow cleaning.

Open the main valve of the argon cylinder, the pressure reducing valve, the ion source valve, the arc valve and the target valve, and the mass flow meter, and argon gas is introduced into the vacuum chamber. The flow rate of the argon gas is controlled to 300-500 sccm, the working pressure is 1.0-1.7 Pa, and the substrate bias voltage is -500--800V. The substrate is glow-cleaned for 10-30 minutes.

After the glow cleaning is finished, turn on the ion source to perform ion bombardment cleaning on the sample, wherein the ion source voltage is 50-90V, the argon gas flow rate is 70-500 sccm, the working pressure is 0.5-1.7Pa, and the base bias voltage is 100-800V, and the cleaning time of the ion bombardment cleaning is 10-30min.

S12. Place the cleaned substrate in the deposition chamber, feed in argon gas with a flow rate of 50-400 sccm, adjust the pressure of the vacuum chamber to 0.2-1.3 Pa, turn on the first target (copper target) and the second target (aluminum target), and control the target power of the first target to 30-70W, control the target power of the second target to 30-70W, and deposit a prefabricated transition layer under the condition that the bias voltage of the substrate is 100-300V.

S13. Take out the sample deposited with the prefabricated transition layer, place it in a container filled with etching solution (sodium hydroxide solution), perform ultrasonic treatment, etch the prefabricated transition layer, form a transition layer with a micro-nano structure array on the surface, and obtain an etched sample.

S14. Cleaning the surface of the etched sample and placing it in a deposition chamber, using acetylene as a working gas, adjusting the pressure in the vacuum chamber to 0.5-1.0 Pa, the ion source voltage to 50-100V, and the substrate bias to 50-200V, depositing a diamond-like carbon layer on the surface of the transition layer of the etched sample.

Example 2

A method for preparing a diamond-like composite layer structure differs from Example 1 in that: the first target material is a metal copper target, the second target material is a metal aluminum target, and the etching solution is potassium hydroxide solution.

Example 3

A method for preparing a diamond-like composite layer structure differs from Example 1 in that: the first target material is a metal copper target, the second target material is a metal aluminum target, and the etching solution is a hydrochloric acid solution.

Example 4

A method for preparing a diamond-like composite layer structure differs from Example 1 in that: the first target material is a metal copper target, the second target material is a metal aluminum target, and the etching solution is sulfuric acid solution.

Example 5

A method for preparing a diamond-like composite layer structure differs from Example 1 in that: the first target material is a metal aluminum target, the second target material is a non-metallic carbon target, and the etching solution is a hydrochloric acid solution.

Example 6

A method for preparing a diamond-like composite layer structure differs from Example 1 in that the first target material is a metal aluminum target, the second target material is a non-metallic carbon target, and the etching solution is sodium hydroxide solution.

Example 7

A method for preparing a diamond-like composite layer structure differs from that of Example 1 in that: the first target material is a metal aluminum target, the second target material is a non-metallic carbon target, and the etching solution is potassium hydroxide solution.

Example 8

A method for preparing a diamond-like composite layer structure differs from Example 1 in that the first target material is a metal aluminum target, the second target material is a non-metallic carbon target, and the etching solution is a sulfuric acid solution.

Example 9

A method for preparing a diamond-like composite layer structure differs from Example 1 in that the first target material is a metal aluminum target, the second target material is a non-metallic silicon target, and the etching solution is sodium hydroxide solution.

Example 10

A method for preparing a diamond-like composite layer structure differs from Example 1 in that: the first target material is a metal aluminum target, the second target material is a non-metallic silicon target, and the etching solution is potassium hydroxide solution.

Comparative example 1

A method for preparing a diamond-like composite layer structure, the difference from Example 1 is that after step S11 is performed, step S12 and step S13 are not performed, and the cleaned substrate is directly placed in a deposition chamber, acetylene is used as a working gas, and the pressure in the vacuum chamber is adjusted to 0.5-1.0Pa, the ion source voltage is 50-100V, and the substrate bias is 50-200V, and a diamond-like carbon layer is deposited on the transition layer surface of the etched sample.

The diamond-like composite layer structure prepared in Examples 1-10 and the diamond-like composite layer structure prepared in Comparative Example 1 were subjected to a water contact angle test experiment, and the test method was as follows:

Test method: shape image analysis method.

The test results are shown in Table 1 below, wherein the test results of Embodiment 1 and Embodiment 2 are shown in Figures 2 and 3 .

Table 1 (Contact angle test results under different conditions)

It can be seen from Table 1 that the diamond-like composite layer structure with surface micro-nano array structure prepared by the embodiment of the present invention has excellent super-hydrophobic properties.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. a preparation method of diamond-like composite layer structure, is characterized in that, comprises the following steps: Provide a substrate, and perform pretreatment, glow cleaning, and ion etching cleaning on the substrate in sequence; wherein, the glow cleaning method is: open the main valve of the argon cylinder, the pressure reducing valve, the ion source valve, the arc valve, the target valve, and the mass flow meter, and feed argon gas into the vacuum chamber, control the flow rate of the argon gas to 300-500 sccm, the working pressure is 1.0-1.7 Pa, and the substrate bias voltage is -500--800V, and the substrate is glow-cleaned, and the cleaning time is 10-30 minutes; placing the cleaned substrate in a deposition chamber, introducing argon gas, adjusting the pressure of the vacuum chamber to 0.2-1.3 Pa, turning on the first target and the second target, controlling the target power of the first target to be 30-70 W, controlling the target power of the second target to be 30-70 W, and depositing a prefabricated transition layer under the condition that the bias voltage of the substrate is 100-300 V; Taking out the sample deposited with the prefabricated transition layer, placing it in a container containing an etching solution, performing ultrasonic treatment, performing etching treatment on the prefabricated transition layer, forming a transition layer with a micro-nano structure array on the surface, and obtaining an etched sample; After the etched sample is subjected to surface cleaning treatment, it is placed in a deposition chamber, and a diamond-like carbon layer is deposited on the surface of the transition layer of the etched sample; Wherein, the first target and the second target are independently selected from metal or non-metallic materials, and the first target is selected from targets soluble in the etching solution, and the second target is selected from targets insoluble in the etching solution. 2. the preparation method of diamond-like composite layer structure as claimed in claim 1, is characterized in that, described first target material, described second target material are selected from metal material, and described metal material comprises iron, aluminum, copper, silver, tin, titanium, germanium; Or The first target material and the second target material are selected from non-metallic materials, and the non-metallic materials include carbon, silicon, and organic polymers. 3. the preparation method of diamond-like composite layer structure as claimed in claim 1, is characterized in that, described first target material is selected from metallic material, and described second target material is selected from nonmetallic material, or The first target is selected from non-metallic materials, the second target is selected from metallic materials, Wherein, the metal material is selected from iron, aluminum, copper, silver, tin, titanium, germanium, and the non-metallic material is selected from carbon, silicon, and organic polymer. 4. The preparation method of the diamond-like composite layer structure as claimed in any one of claims 1 to 3, wherein said etching solution is selected from acidic solution, and said acidic solution is selected from at least one of nitric acid, sulfuric acid, hydrochloric acid, hydrofluoric acid, organic acid; or The etching solution is selected from alkaline solutions, and the alkaline solution is selected from at least one of sodium hydroxide, potassium hydroxide, calcium hydroxide, lithium hydroxide, and organic bases. 5. The preparation method of the diamond-like composite layer structure as claimed in any one of claims 1 to 3, wherein, in the step of depositing a diamond-like carbon layer on the surface of the transition layer of the etched sample, the etched sample is placed in the deposition chamber after the surface cleaning treatment, with acetylene as the working gas, and the pressure in the vacuum chamber is adjusted to be 0.5 ~ 1.0Pa, the ion source voltage is 50 ~ 100V, and the substrate bias is 50 ~ 200V, and the diamond-like carbon is deposited on the transition layer surface of the etched sample layers. 6. A diamond-like composite layer structure prepared by the preparation method described in any one of claims 1-5, wherein the diamond-like composite layer structure comprises a substrate, a transition layer arranged on the surface of the substrate, a diamond-like layer arranged on the surface of the transition layer away from the substrate, wherein, The transition layer protrudes on the side away from the substrate to form a micro-nano array structure, and the surface of the diamond-like layer away from the substrate is a micro-nano array surface; In the micro-nano array structure of the diamond-like layer, the ratio of the height of the micro-nano unit to the distance between adjacent micro-nano units is 1: (0.5-1.5). 7. The diamond-like composite layer structure according to claim 6, wherein in the transition layer, the height of the micro-nano array structure is 0.5 micron to 2 micron, and the distance between adjacent micro-nano units in the micro-nano array structure is 0.1 micron to 2 micron. 8. The diamond-like composite layer structure as claimed in claim 6, wherein, in the micro-nano array surface of the diamond-like layer, the height of the micro-nano array is 0.5 micron to 2 micron, and the distance between adjacent micro-nano units in the micro-nano array is 0.1 micron to 2 micron. 9. The diamond-like composite layer structure according to any one of claims 6 to 8, wherein the transition layer is selected from a metal layer or a non-metal layer, wherein, The metal layer is one of iron layer, aluminum layer, copper layer, silver layer, tin layer, titanium layer, germanium layer, The non-metallic layer is one of carbon layer, silicon layer and organic polymer layer. 10. The diamond-like composite layer structure according to any one of claims 6 to 8, wherein the substrate is selected from one of carbon steel substrates, stainless steel substrates, high-grade steel substrates, cemented carbide substrates, and ceramic substrates.