Composite coating layer and preparation method thereof, electronic product
By setting a first connecting layer and a second connecting layer between the substrate and the silicon layer, the problem of poor adhesion between the silicon layer and the substrate is solved, achieving high adhesion and high conductivity of the composite coating and extending its service life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANGDONG XIAOTIANCAI TECH CO LTD
- Filing Date
- 2024-12-18
- Publication Date
- 2026-06-19
AI Technical Summary
Poor bonding between the silicon layer and the substrate leads to increased interface resistance, decreased electron transport performance, poor stability of the composite coating, and short service life.
A first interconnect layer and a second interconnect layer are disposed between the substrate and the silicon layer. Part of the metal in the first interconnect layer is located in the substrate. The coefficient of thermal expansion of the second interconnect layer is between that of the first interconnect layer and the silicon layer. Through the synergistic effect of the first interconnect layer and the second interconnect layer, the bonding tightness is improved and the difference in thermal expansion is buffered.
It improves the adhesion and conductivity of the composite coating, reduces interface defects, and extends service life.
Smart Images
Figure CN122235641A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of electronic coating materials technology, and in particular to a composite coating and its preparation method, as well as electronic products. Background Technology
[0002] Preparing composite coatings with silicon layers is quite challenging because silicon is hard and brittle, and has a low coefficient of thermal expansion. These characteristics result in poor bonding between silicon and the substrate, which not only increases the interfacial resistance between the silicon layer and the substrate, affecting electron transport performance and leading to lower conductivity in the composite coating, but also results in more defects at the interface, poor stability, and a shorter lifespan for the composite coating. Summary of the Invention
[0003] This invention discloses a composite coating and its preparation method, as well as an electronic product. The composite coating has high adhesion and high conductivity.
[0004] In a first aspect, embodiments of this application disclose a composite coating, the composite coating comprising:
[0005] Base;
[0006] A connecting layer is disposed on the substrate. The connecting layer includes a first connecting layer and a second connecting layer disposed on the first connecting layer. The first connecting layer is a metal layer and a portion of the metal in the first connecting layer is located in the substrate.
[0007] A silicon layer is disposed on the side surface of the second interconnect layer opposite to the substrate, and the coefficient of thermal expansion of the second interconnect layer is between the coefficient of thermal expansion of the first interconnect layer and the coefficient of thermal expansion of the silicon layer.
[0008] Furthermore, the first connecting layer includes a first metal layer and a second metal layer, the first metal layer is disposed on the substrate, the second metal layer is disposed between the first metal layer and the second connecting layer, and the density of the second metal layer is higher than that of the first metal layer.
[0009] Furthermore, the first metal layer has pores, and a portion of the metal in the second metal layer fills the pores of the first metal layer.
[0010] Furthermore, the material of the second connecting layer includes metals and metal compounds, wherein the metal in the second connecting layer is of the same type as the metal in the second metal layer, and the metal compounds include metal nitrides and / or metal carbides;
[0011] Wherein, by mass percentage, the second connecting layer comprises: 30% to 70% of the metal compound and 30% to 70% of the metal;
[0012] Alternatively, the material of the second connecting layer may further include a silicon-containing substance, which includes at least one of elemental silicon and silicon alloy. By mass percentage, the second connecting layer comprises: 30% to 70% of the metal compound and the silicon-containing substance, and 30% to 70% of the metal.
[0013] Furthermore, the thickness of the first metal layer is 50 nm to 100 nm;
[0014] The thickness of the second metal layer is 150 nm to 250 nm;
[0015] The thickness of the second connecting layer is 50nm to 100nm.
[0016] Furthermore, the silicon layer includes a first silicon layer disposed close to the substrate, a second silicon layer disposed away from the substrate, and a transition layer disposed between the first silicon layer and the second silicon layer, wherein the transition layer is a metal layer and / or a silicon alloy layer.
[0017] Furthermore, a first silicon layer, a transition layer, and a second silicon layer constitute a group of silicon layers, and the composite coating includes several groups of silicon layers, wherein the first layer disposed outside the second connecting layer is the first silicon layer.
[0018] Further, the thickness ratio of the first silicon layer to the transition layer is 1:1 to 10:1; and / or,
[0019] The thickness ratio of the second silicon layer to the transition layer is 1:1 to 10:1.
[0020] Furthermore, the thickness of the first silicon layer is 5 nm to 4000 nm;
[0021] The thickness of the transition layer is 5 nm to 500 nm;
[0022] The thickness of the second silicon layer is 5nm to 4000nm.
[0023] Furthermore, the composite coating also includes an ion bombardment layer disposed between the substrate and the connecting layer, the ion bombardment layer being configured to be formed by bombarding the substrate with positively charged metal ions.
[0024] Furthermore, the ion source of the positively charged metal ions includes at least one of Ni, Cr, Ti, Al, or stainless steel.
[0025] Furthermore, the surface dyne value of the substrate is >32 dyn / cm; and / or,
[0026] The substrate material includes at least one of metallic and non-metallic materials, wherein the metallic material includes at least one of aluminum, stainless steel, and copper, and the non-metallic material includes at least one of polyimide and polyetherimide; and / or,
[0027] The metal in the first bonding layer includes at least one of Ni, Cr, Ti, Al, Cu, and stainless steel; and / or,
[0028] The composite coating further includes a surface layer disposed on the side of the silicon layer facing away from the substrate; wherein the thickness of the surface layer is 200 nm to 500 nm; and / or,
[0029] The surface layer is a metal layer or a silicon alloy layer; and / or,
[0030] The silicon layer is either a silicon elemental layer or a mixture layer; wherein, when the silicon layer is a mixture layer, the material of the mixture layer includes silicon elemental and metallic elemental, and the mass percentage of silicon elemental in the mixture layer is greater than or equal to 50%.
[0031] Secondly, embodiments of this application disclose a method for preparing the composite coating according to any one of the first aspects, the method comprising the following steps:
[0032] The first connecting layer is prepared on the substrate;
[0033] The second connection layer is fabricated on the first connection layer;
[0034] The silicon layer is prepared on the second interconnect layer.
[0035] Furthermore, the step of preparing the first connecting layer on the substrate includes: preparing a first metal layer using a vacuum deposition method with an arc target, and preparing a second metal layer on the first metal layer using a column target.
[0036] Further, the step of preparing the second connecting layer on the first connecting layer includes: introducing nitrogen gas and / or acetylene gas, and preparing the second connecting layer on the first connecting layer using a metal target;
[0037] Alternatively, nitrogen and / or acetylene gas can be introduced, and the second interconnect layer can be fabricated on the first interconnect layer using a metal target and a silicon pillar target.
[0038] Furthermore, prior to the step of fabricating the first connecting layer on the substrate, the fabrication method further includes:
[0039] The precursor substrate is cleaned and heated to remove the oxide layer, oil, and impurities from the precursor substrate.
[0040] The precursor substrate is subjected to glow discharge cleaning to obtain the substrate; and / or,
[0041] After the step of preparing the silicon layer on the second interconnect layer, the preparation method further includes: preparing the surface layer on the side of the silicon layer facing away from the substrate.
[0042] Furthermore, prior to the step of preparing the first interconnect layer on the substrate, the preparation method further includes: depositing positively charged metal ions onto the substrate and connecting a negative bias voltage onto the substrate to accelerate the positively charged metal ions to bombard the surface of the substrate, thereby obtaining an ion bombardment layer.
[0043] Thirdly, embodiments of this application disclose an electronic product comprising: a composite coating as described in any of the first aspects, or a composite coating prepared by the method described in the second aspect.
[0044] Compared with the prior art, this application has at least the following beneficial effects:
[0045] This application provides a composite coating, which sequentially includes a substrate, a bonding layer, a silicon layer, and a surface layer. The bonding layer includes a first bonding layer and a second bonding layer. The coefficient of thermal expansion of the second bonding layer is between that of the first bonding layer and the silicon layer. A portion of the metal in the first bonding layer is located in the substrate. Through the synergistic effect of the first bonding layer and the second bonding layer, the bonding tightness of the composite coating is improved to a greater extent, thereby enhancing its conductivity.
[0046] Specifically, since the metal of the first connecting layer is located on the substrate, the metal is anchored to the substrate, thereby increasing the bonding force between the first connecting layer and the substrate and preventing the first connecting layer from detaching from the substrate. In addition, since the coefficient of thermal expansion of the second connecting layer is between that of the first connecting layer and the silicon layer, the second connecting layer can effectively buffer the difference in thermal expansion between the silicon layer and the first connecting layer, reducing problems such as cracking and delamination of the composite coating caused by thermal stress, thereby increasing the bonding force between the silicon layer and the connecting layer. In other words, through the synergistic effect of the first and second connecting layers, a high degree of bonding tightness between the silicon layer and the substrate is ensured, which helps to reduce charge accumulation and scattering at the interface, lower the interface resistance, and ensure that the final composite coating has high adhesion and high conductivity. Attached Figure Description
[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0048] Figure 1 This is a schematic diagram of the structure of the composite coating provided in the embodiments of this application;
[0049] Figure 2 yes Figure 1 A magnified view of part A in the image;
[0050] Figure 3 This is a schematic diagram of a composite coating provided in an embodiment of this application (the silicon layer in the composite coating is one layer);
[0051] Figure 4 This is a schematic diagram of a composite coating provided in an embodiment of this application (the number of silicon layers in the composite coating is N).
[0052] Icons: 1. Substrate; 2. Connecting layer; 21. First connecting layer; 21a. Metal in the first connecting layer; 211. First metal layer; 212. Second metal; 22. Second connecting layer; 3. Silicon layer; 31. First silicon layer; 32. Second silicon layer; 33. Transition layer; 4. Ion bombardment layer; 5. Surface layer. Detailed Implementation
[0053] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0054] In this invention, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing the invention and its embodiments, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation.
[0055] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in certain situations to indicate a dependency or connection. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.
[0056] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, elements, or components (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.
[0057] The technical solutions provided by the present invention will be further described below with reference to the embodiments and accompanying drawings.
[0058] When preparing composite coatings with silicon layers, the silicon atoms in the silicon layer are linked together by covalent bonds. This bonding method results in silicon having poor ductility and high resistance to deformation, meaning silicon is hard and brittle, and also has a low coefficient of thermal expansion. These characteristics of silicon lead to poor adhesion between the silicon layer and the substrate, resulting in numerous interface defects.
[0059] Therefore, due to the low adhesion between the silicon layer and the substrate and the large number of interface defects, the interfacial resistance between the silicon layer and the substrate increases, the electron transport performance decreases, and the conductivity of the composite coating decreases. Furthermore, it makes the silicon layer easy to detach from the substrate, and the composite coating has poor resistance to corrosive substances, resulting in poor stability of the composite coating and a reduced service life.
[0060] Based on the above problems, this application provides a composite coating in which the silicon layer has a high degree of adhesion to the substrate, which helps to improve the adhesion, conductivity and service life of the composite coating.
[0061] Firstly, embodiments of this application disclose a composite coating, such as... Figure 1 As shown, the composite coating includes:
[0062] Base 1;
[0063] Connection layer 2 is disposed on substrate 1. Connection layer 2 includes a first connection layer 21 and a second connection layer 22 disposed on the first connection layer 21. The first connection layer 21 is a metal layer and a portion of the metal in the first connection layer 21 is located in substrate 1.
[0064] Silicon layer 3 is disposed on the side surface of the second interconnect layer 22 away from the substrate 1. The coefficient of thermal expansion of the second interconnect layer 22 is between the coefficient of thermal expansion of the first interconnect layer 21 and the coefficient of thermal expansion of the silicon layer 3.
[0065] The composite coating disclosed in this application includes a substrate 1, a connecting layer 2, and a silicon layer 3. The connecting layer 2 includes a first connecting layer 21 and a second connecting layer 22. Since a portion of the metal in the first connecting layer 21 is located in the substrate 1, this portion of metal can act as an anchor, better bonding the substrate 1 and the first connecting layer 21 together, thereby improving the adhesion of the composite coating. In addition, since the first connecting layer 21 is a metal layer, and since the thermal expansion coefficients of metal and silicon differ significantly, this application sets the thermal expansion coefficient of the second connecting layer 22 to be between that of the first connecting layer 21 and the silicon layer 3. This allows the second connecting layer 22 to act as a buffer layer, effectively buffering the thermal expansion difference between the first connecting layer 21 and the silicon layer 3. This helps avoid the problem of poor bonding tightness between the silicon layer 3 and the first connecting layer 21 caused by thermal expansion, further improving the bonding tightness between the silicon layer 3 and the substrate 1, reducing interface defects, and thus improving the adhesion and conductivity of the composite coating.
[0066] In summary, by providing a first interconnect layer 21 and a second interconnect layer 22 between the substrate 1 and the silicon layer 3, this application achieves a high degree of connection between the substrate 1 and the first interconnect layer 21, and a high degree of connection between the second interconnect layer 22 and the silicon layer 3. Therefore, the synergistic effect of the two helps to reduce interface defects and improve the adhesion, conductivity and service life of the composite coating.
[0067] In addition, such as Figure 2 As shown, Figure 2 for Figure 1 An enlarged view of region A in the middle, where, Figure 1 The patterns filling each layer are merely to better illustrate the positional relationship between the different layers. Figure 2 To better illustrate the arrangement of the metal in the first connecting layer 21, Figure 2 The first connecting layer 21 and the substrate 1 are not filled with patterns. The fact that some metal 21a in the first connecting layer 21 is located in the substrate 1 means that during the preparation of the first connecting layer 21, the metal 21a bombards the substrate 1, so some of the metal 21a enters the substrate 1, and the other part of the metal 21a is stacked on the surface of the substrate 1 to form a layer structure. The metal 21a that enters the substrate 1 is like a latch, locking the first connecting layer 21 and the substrate 1 together. This interlocking structure greatly increases the bonding force between the first connecting layer 21 and the substrate 1, and improves the adhesion performance of the composite coating.
[0068] In one optional embodiment, when the coefficient of thermal expansion of the metal in the first interconnect layer is higher than that of the silicon material, the coefficient of thermal expansion of the second interconnect layer being between the coefficient of thermal expansion of the first interconnect layer and the coefficient of thermal expansion of the silicon layer means that the coefficient of thermal expansion of the second interconnect layer is higher than that of the silicon layer and lower than that of the first interconnect layer. In another optional embodiment, when the coefficient of thermal expansion of the metal in the first interconnect layer is lower than that of the silicon material, the coefficient of thermal expansion of the second interconnect layer being between the coefficient of thermal expansion of the first interconnect layer and the coefficient of thermal expansion of the silicon layer means that the coefficient of thermal expansion of the second interconnect layer is lower than that of the silicon layer and higher than that of the first interconnect layer.
[0069] The substrate material includes at least one of metallic and non-metallic materials. The metallic materials include at least one of aluminum, stainless steel, and copper, while the non-metallic materials include at least one of polyimide and polyetherimide. Preferably, when the substrate material is metallic, not only is the metal in the first connecting layer located within the substrate, but the metal in the second connecting layer is also chemically bonded to the substances in the substrate, thereby further improving the bonding strength between the substrate and the first connecting layer.
[0070] The silicon layer can be a single silicon layer or a mixture layer; when the silicon layer is a mixture layer, the material of the mixture layer includes single silicon and metal elements, the mass percentage of single silicon in the mixture layer is greater than or equal to 50%, and when the silicon layer is a mixture layer, it can better alleviate the expansion coefficient between different layers, thereby improving the adhesion of the film layer.
[0071] Furthermore, the first connecting layer includes a first metal layer and a second metal layer, the first metal layer is disposed on the substrate, the second metal layer is disposed between the first metal layer and the second connecting layer, and the density of the second metal layer is higher than that of the first metal layer.
[0072] Since the second metal layer is denser than the first metal layer, the second metal layer, as an intermediate layer, has good bonding with the first metal layer and the second connecting layer, and has fewer interface defects, thereby improving the adhesion of the composite coating to a greater extent.
[0073] The density of the second metal layer is higher than that of the first metal layer, meaning that both the second and first metal layers contain pores, but the second metal layer has fewer pores than the first metal layer. Furthermore, the density of the second metal layer can be increased by controlling the fabrication processes of the first and second metal layers. For example, an arc target can be used to fabricate the first metal layer, while a column target can be used to fabricate the second metal layer.
[0074] In one optional embodiment, the metal in the first metal layer and the metal in the second metal layer are the same type, such as both the first metal layer and the second metal layer being chromium layers; in another optional embodiment, the metal in the first metal layer and the metal in the second metal layer are different types, such as the first metal layer being a chromium layer and the second metal layer being a titanium layer.
[0075] Furthermore, since the first metal layer has many pores, in order to further improve the bonding stability between the first metal layer and the second metal layer, some of the metal in the second metal layer is filled into the pores of the first metal layer. Therefore, the metal filled into the pores helps to improve the compactness of the first metal layer, effectively reduces the defects of the first metal layer, improves the bonding tightness between the first metal layer and the second metal layer, and improves the adhesion of the composite coating.
[0076] Furthermore, the material of the second connecting layer includes metals and metal compounds, wherein the metals in the second connecting layer are of the same type as the metals in the second metal layer, and the metal compounds include metal nitrides and / or metal carbides.
[0077] In one alternative embodiment, the material of the second connecting layer includes metal and metal compound, and by mass percentage, the second connecting layer includes: 30% to 70% metal compound and 30% to 70% metal element.
[0078] In another alternative embodiment, the material of the second connecting layer includes metal, metal compound, and silicon-containing material, wherein the silicon-containing material includes at least one of elemental silicon and silicon alloy. By mass percentage, the second connecting layer comprises: 30% to 70% metal compound and silicon-containing material, and 30% to 70% elemental metal.
[0079] When the material of the second connecting layer is the aforementioned material, and by controlling its mass content, the coefficient of thermal expansion of the second connecting layer is between that of the first connecting layer and the silicon layer, resulting in a high degree of bonding between the second connecting layer and the first connecting layer and the silicon layer, which helps to further improve the adhesion of the composite coating.
[0080] In addition, the thickness of the first metal layer is 50nm to 100nm. When the thickness of the first metal layer is within the above range, it can provide a sufficient amount of metal to enter the substrate, thereby ensuring a high degree of bonding between the substrate and the first metal layer.
[0081] Furthermore, the thickness of the second metal layer is 150 nm to 250 nm. When the thickness of the second metal layer is within this range, it ensures a high degree of bonding between the second metal layer, the first metal layer, and the second connecting layer. Even when the first metal layer has pores, this thickness allows a suitable amount of metal to enter the pores, further improving the density of the first metal layer, reducing interface defects, further enhancing the bonding between the first and second metal layers, and reducing resistance.
[0082] Furthermore, the thickness of the second connecting layer is 50nm to 100nm. When the thickness of the second connecting layer is within the above range, it helps to enhance its buffering effect, effectively improve the problem of decreased adhesion caused by thermal expansion differences, and also helps with electron transport.
[0083] For silicon materials, the strong covalent bonds between silicon atoms result in significant internal stress within the silicon layer, and this stress increases with the thickness of the silicon layer. This application further improves the silicon layer by comprising a first silicon layer disposed close to the substrate, a second silicon layer disposed away from the substrate, and a transition layer disposed between the first and second silicon layers. The transition layer is a metal layer and / or a silicon alloy layer. This arrangement helps reduce the internal stress within the silicon layer.
[0084] Specifically, since the transition layer is a metal layer or a silicon alloy layer, when the above materials are used, the transition layer has high ductility. Therefore, under the action of the transition layer, some of the internal stress in the silicon layer will be released and dispersed to a certain extent, so that the internal stress in the silicon layer will not be excessively concentrated, which helps to reduce the internal stress of the composite coating and avoid delamination caused by severe stress accumulation.
[0085] Since metals have higher ductility than silicon alloys, when the transition layer is a metal layer, it can effectively withstand and disperse stress, resulting in lower internal stress in the composite coating and thus helping to avoid delamination caused by stress accumulation. Since the crystals in the silicon alloy have high compatibility with the crystals in the first and second silicon layers, when the transition layer is a silicon alloy layer, the connection stability between the transition layer and the first and second silicon layers is high, which helps to improve the bonding force between the transition layer and the first and second silicon layers and further optimize the adhesion performance of the composite coating.
[0086] It should be noted that, in order to further reduce the impact of the transition layer between the first and second silicon layers on the adhesion performance, this application sets the thickness ratio of the first silicon layer to the transition layer to be 1:1 to 10:1, and the thickness ratio of the second silicon layer to the transition layer to be 1:1 to 10:1. Therefore, when the thicknesses of the first silicon layer, the second silicon layer, and the transition layer meet the above ranges, it can not only further reduce the internal stress of the composite coating, but also help reduce the impact on the adhesion of the composite coating, and further improve the wear resistance, impact resistance, and other physical properties of the composite coating. Preferably, when the thickness of the transition layer is relatively thin, it not only helps to reduce the internal stress of the composite coating, but also helps to further avoid the problems of increased interface number and decreased adhesion performance caused by the setting of the transition layer.
[0087] Furthermore, a first silicon layer, a transition layer, and a second silicon layer constitute a group of silicon layers, and the composite coating includes several groups of silicon layers, wherein the first layer disposed outside the second connecting layer is the first silicon layer. This alternating arrangement allows the transition layer to more effectively disperse and alleviate internal stress, contributing to a significant reduction in the internal stress of the composite coating.
[0088] Furthermore, the thickness of the first silicon layer is 5 nm to 4000 nm; the thickness of the transition layer is 5 nm to 500 nm; and the thickness of the second silicon layer is 5 nm to 4000 nm. When the thicknesses of the first silicon layer, the transition layer, and the second silicon layer are within the above ranges, they can more effectively disperse the internal stress of the silicon layer and reduce the internal stress of the composite coating.
[0089] Furthermore, the composite coating also includes an ion bombardment layer disposed between the substrate and the bonding layer, the ion bombardment layer being configured to be formed by bombarding the substrate with positively charged metal ions.
[0090] When positively charged metal ions bombard the substrate, some of the positively charged metal ions enter the substrate and connect with the substrate material, thereby improving the bonding force between the ion-bombarded layer and the substrate and further enhancing the adhesion performance of the composite coating.
[0091] The ion source for the positively charged ions includes at least one of Ni, Cr, Ti, Al, or stainless steel.
[0092] To further improve the bonding force between the substrate and the first connecting layer, the surface dyne value of the substrate is set to >32 dyn / cm. The dyne value measures the magnitude of the surface tension of the substrate. When the dyne value of the substrate is within the above range, it indicates that the substrate surface has a high cleaning effect, which is more conducive to placing the first connecting layer on the substrate, so that the substrate and the first connecting layer have a high bonding strength.
[0093] Furthermore, the metal in the first bonding layer includes at least one of Ni, Cr, Ti, Al, Cu, and stainless steel.
[0094] To ensure good contact between the composite coating and the external environment and improve the stability of electronic conduction, the composite coating of this application further includes a surface layer on the side of the silicon layer facing away from the substrate. By further setting the thickness of the surface layer to 200 nm to 500 nm, the conductivity stability of the composite coating in contact with the external environment is further improved.
[0095] In addition, the surface layer is a metal layer or a silicon alloy layer.
[0096] In one alternative implementation, such as Figure 3 As shown, the first silicon layer 31, the transition layer 33, and the second silicon layer 32 are all single layers. The composite coating includes, in sequence, a substrate 1, an ion bombardment layer 4, a connecting layer 2, a silicon layer 3, and a surface layer 5. The connecting layer 2 includes a first connecting layer 21 and a second connecting layer 22. The first connecting layer 21 includes a first metal layer 211 and a second metal layer 212. The first metal layer 211 is located between the second metal layer 212 and the ion bombardment layer 4. The second connecting layer 22 is provided with the first silicon layer 31, the transition layer 33, and the second silicon layer 32 in sequence. The first silicon layer 31 is located between the transition layer 33 and the second connecting layer 22, and the second silicon layer 32 is located between the transition layer 33 and the surface layer 5.
[0097] In one alternative implementation, such as Figure 4 As shown, the number of layers of the first silicon layer 31, the transition layer 33, and the second silicon layer 32 is N. The second connecting layer 22 is alternately provided with the first silicon layer 31, the transition layer 33, and the second silicon layer 32, where N is a positive integer greater than or equal to two. The connecting layer 2 includes the first connecting layer 21 and the second connecting layer 22. The first connecting layer 21 includes the first metal layer 211 and the second metal layer 212. The first metal layer 211 is located between the second metal layer 212 and the ion bombardment layer 4. The first layer outside the second connecting layer 22 is the first silicon layer 31.
[0098] Secondly, embodiments of this application disclose a method for preparing a composite coating as described in the first aspect, the method comprising the following steps:
[0099] A first connecting layer is prepared on the substrate;
[0100] A second connecting layer is fabricated on the first connecting layer;
[0101] A silicon layer is fabricated on the second interconnect layer.
[0102] Furthermore, the step of preparing the first connecting layer on the substrate includes: preparing the first metal layer using an arc target by vacuum deposition, and preparing the second metal layer on the first metal layer using a column target.
[0103] In this process, due to the high sputtering intensity of the arc target, some of the metal in the first metal layer can enter the substrate, and the depth of entry is ensured to be high. This results in a high degree of bonding between the first metal layer and the substrate. The film layer obtained by sputtering with the column target has a high density, which makes the density of the first metal layer higher than that of the second metal layer. This allows the second metal layer to act as an intermediate layer and have high bonding performance with the first metal layer and the second connecting layer, respectively.
[0104] In an alternative embodiment, when the second connecting layer comprises an elemental metal and a metal compound, the step of preparing the second connecting layer on the first connecting layer includes: introducing nitrogen and / or acetylene gas, and preparing the second connecting layer on the first connecting layer using a metal target.
[0105] In another alternative embodiment, when the second connecting layer comprises a metal element, a metal compound, or a silicon-containing substance, the step of preparing the second connecting layer on the first connecting layer includes: introducing nitrogen and / or acetylene gas, and preparing the second connecting layer on the first connecting layer using a metal target and a silicon pillar target.
[0106] Furthermore, prior to the step of fabricating the first connecting layer on the substrate, the fabrication method further includes:
[0107] The precursor substrate is cleaned and heated to remove the oxide layer, oil, and impurities from the precursor substrate.
[0108] The precursor substrate was subjected to glow discharge cleaning to obtain the substrate.
[0109] The steps of cleaning and heating the precursor substrate include: removing the oxide layer and oil stains from the precursor substrate by alkaline washing, acid washing and neutralization, water washing and baking drying; and placing the precursor substrate in a deposition furnace to remove the adsorbed impurities (i.e., impurity gases) on the precursor substrate by high temperature, thereby improving the cleanliness of the precursor substrate surface.
[0110] The steps of glow discharge cleaning of the precursor substrate include: filling the deposition furnace with argon gas, then applying a negative pressure to the precursor substrate to generate glow discharge, performing glow discharge cleaning, and thus obtaining the substrate.
[0111] Furthermore, prior to the step of preparing the first connecting layer on the substrate, the preparation method further includes: depositing positively charged metal ions onto the substrate and connecting a negative bias voltage onto the substrate to accelerate the positively charged metal ions to bombard the surface of the substrate, thereby obtaining an ion bombardment layer.
[0112] Furthermore, after the step of preparing a silicon layer on the second interconnecting layer, the preparation method further includes: preparing a surface layer on the surface of the silicon layer using a metal arc target, a pillar target, or a silicon pillar target.
[0113] The preparation of each functional layer of the composite coating can be carried out by one of physical vapor deposition, magnetron sputtering or chemical vapor deposition.
[0114] Thirdly, embodiments of this application disclose an electronic product, which includes: a composite coating as described in any of the first aspects, or a composite coating prepared by any of the preparation methods described in the second aspect.
[0115] The composite coating, its preparation method, and electronic products of this application will be further described below with reference to more specific embodiments.
[0116] Example 1:
[0117] This application provides a composite coating comprising a stainless steel substrate, a first connecting layer, a second connecting layer, a silicon layer, and a surface layer. The first connecting layer comprises a first metal layer with a thickness of 100 nm and a second metal layer with a thickness of 150 nm. The second metal layer has a higher density than the first metal layer. Both the first and second metal layers are chromium metal layers, with some chromium in the second metal layer filling the pores in the first metal layer, and some chromium in the first metal layer located within the stainless steel substrate. The second connecting layer has a thickness of 100 nm and is composed of 50 wt% chromium nitride and 50 wt% chromium. The coefficient of thermal expansion of the second connecting layer is higher than that of the second metal layer but lower than that of the first metal layer. The silicon layer comprises a first silicon layer with a thickness of 2500 nm, a transition layer with a thickness of 500 nm, and a second silicon layer with a thickness of 2500 nm. The transition layer is composed of a silicon-chromium alloy and chromium. The surface layer has a thickness of 200 nm and is composed of a silicon-chromium alloy and chromium. The first silicon layer, the second silicon layer, and the transition layer are each a single layer.
[0118] The preparation method of the above composite coating includes:
[0119] The steps for preparing the substrate include:
[0120] The stainless steel precursor substrate is subjected to alkaline washing, acid washing, and water rinsing. After drying, the cleaned stainless steel precursor substrate is fixed on a rack and placed in a magnetron sputtering coating machine. The furnace is then evacuated to a vacuum of 1×10⁻⁶. -2 When the pressure is below pa, argon gas is introduced into the furnace, and a negative bias voltage is applied to the surface of the stainless steel precursor substrate to perform a glow discharge cleaning step for 8 minutes to obtain the substrate.
[0121] Preparation of the ion bombardment layer: Argon gas is introduced, the chromium arc target is turned on, a negative bias voltage is applied to the substrate surface, and ion bombardment is performed for 10 minutes.
[0122] Preparation of the connecting layer: Argon gas is introduced, the chromium arc target is turned on, and a negative bias voltage is applied to the product surface to deposit the first metal layer; the chromium arc target is turned off, the chromium pillar target is turned on, and the second metal layer is deposited; finally, a small amount of nitrogen gas is introduced to obtain the second connecting layer.
[0123] Silicon layer preparation: Argon gas is introduced and the silicon target power supply is turned on to obtain the first silicon layer; the silicon target and chromium arc target power supplies are turned on to obtain the transition layer; the silicon target is turned on to obtain the second silicon layer.
[0124] Surface layer preparation: The power supplies for the silicon pillar target and the chromium arc target are turned on simultaneously to obtain the surface layer.
[0125] Example 2:
[0126] The only difference between this embodiment and Embodiment 1 is that the metal of the second metal layer is titanium, the material of the second connecting layer includes titanium and titanium nitride, the total thickness of the silicon layer is 4800nm, the number of layers of the first silicon layer, the second silicon layer, and the transition layer is sixteen, the thickness ratio of the first silicon layer to the transition layer is 1:1, and the thickness ratio of the second silicon layer to the transition layer is 1:1.
[0127] Example 3:
[0128] The only difference between this embodiment and Embodiment 1 is that the composite coating of this application does not have a second metal layer.
[0129] Example 4:
[0130] The only difference between this embodiment and Embodiment 1 is that the density of the second metal layer in this application is equal to or less than that of the first metal layer.
[0131] Example 5:
[0132] The only difference between this embodiment and Embodiment 1 is that the material of the second connecting layer includes 20% chromium nitride and 80% chromium.
[0133] Example 6:
[0134] The only difference between this embodiment and Embodiment 1 is that the number of layers in the first silicon layer, the second silicon layer, and the transition layer are all sixteen, the thickness ratio of the first silicon layer to the transition layer is 10:1, and the thickness ratio of the second silicon layer to the transition layer is 10:1.
[0135] Example 7:
[0136] The only difference between this embodiment and Embodiment 1 is that the number of layers in the first silicon layer, the second silicon layer, and the transition layer are all sixteen, the thickness ratio of the first silicon layer to the transition layer is 1:1, and the thickness ratio of the second silicon layer to the transition layer is 1:1.
[0137] Comparative Example 1:
[0138] The only difference between this comparative example and Example 1 is that the composite coating does not contain a second connecting layer, and the number of layers of the first silicon layer, the second silicon layer, and the transition layer is sixteen. The thickness ratio of the first silicon layer to the transition layer is 1:1, and the thickness ratio of the second silicon layer to the transition layer is 1:1.
[0139] Comparative Example 2:
[0140] The only difference between this comparative example and Example 1 is that the expansion coefficient of the second connecting layer is higher than that of the second metal layer.
[0141] Comparative Example 3:
[0142] The only difference between this comparative example and Example 1 is that the composite coating does not contain a first bonding layer.
[0143] Test Result 1:
[0144] The adhesion properties of the composite coatings prepared in Examples 1 to 7 and Comparative Examples 1 to 3 were tested, and the test results are shown in Table 1 below.
[0145] Adhesion: The adhesion of the composite coatings in the examples and comparative examples was tested using the test method of GB / T 9286-2021.
[0146] Table 1. Data from Examples and Comparative Cases
[0147] Serial Number Adhesion Serial Number Adhesion Example 1 5B Example 6 5B Example 2 5B Example 7 5B Example 3 4B Comparative Example 1 4B Example 4 4B Comparative Example 2 3B Example 5 4B Comparative Example 3 3B
[0148] Analysis of the data from Examples 2, 6, and 7 and Comparative Example 1 shows that the number of layers in both examples and comparative examples is sixteen, and the performance of examples is better than that of comparative example 1. This is because the composite coatings in examples all contain a second connecting layer, and the coefficient of thermal expansion of the second connecting layer is between that of the first connecting layer and the silicon layer. Therefore, the second connecting layer can effectively buffer the difference in thermal expansion between the silicon layer and the first connecting layer, reduce problems such as cracking and delamination of the composite coating caused by thermal stress, and thus increase the bonding force between the silicon layer and the connecting layer.
[0149] Analysis of the data from Examples 1, 2 to 5, and Comparative Examples 2 and 3 shows that the performance of Examples 1 is better than that of Comparative Example 2. This is because the coefficient of thermal expansion of the second connecting layer in Examples 1 is between that of the first connecting layer and the silicon layer. Therefore, the second connecting layer can effectively buffer the difference in thermal expansion between the silicon layer and the first connecting layer, thereby increasing the bonding force between the silicon layer and the connecting layer. The performance of Examples 2 is better than that of Comparative Example 3. This is because the composite coating in Examples 2 contains a first connecting layer. The metal of the first connecting layer is located on the substrate, which anchors the metal on the substrate, thereby increasing the bonding force between the first connecting layer and the substrate and improving the adhesion of the composite coating.
[0150] Analysis of the data from Examples 1, 3, and 4 shows that the performance of Example 1 is better than that of Examples 3 and 4. This is because Example 1 contains a second metal layer, and the density of the second metal layer is higher than that of the first metal layer. Therefore, as an intermediate layer, the second metal layer has good bonding with the first metal layer and the second connecting layer, and the interface defects are small, thereby improving the adhesion of the composite coating to a greater extent.
[0151] Analysis of the data from Examples 1 and 5 shows that the performance of Example 1 is better than that of Example 5. This is because the matching degree between the second connecting layer and the second metal layer and silicon layer is higher in Example 1, which can effectively reduce the difference in the expansion coefficient between the second metal layer and the silicon layer, thereby improving the adhesion.
[0152] Analysis of the data from Examples 2, 6, and 7 shows that the data from Examples 2, 6, and 7 are all superior, indicating that even when the number of silicon layers in this application is large, it still has high adhesion.
[0153] The composite coating, its preparation method, and electronic products disclosed in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the composite coating, its preparation method, and electronic products. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.
Claims
1. A composite coating, characterized in that, The composite coating includes: Base; A connecting layer is disposed on the substrate. The connecting layer includes a first connecting layer and a second connecting layer disposed on the first connecting layer. The first connecting layer is a metal layer and a portion of the metal in the first connecting layer is located in the substrate. A silicon layer is disposed on the side surface of the second interconnect layer opposite to the substrate, and the coefficient of thermal expansion of the second interconnect layer is between the coefficient of thermal expansion of the first interconnect layer and the coefficient of thermal expansion of the silicon layer.
2. The composite coating according to claim 1, characterized in that, The first connecting layer includes a first metal layer and a second metal layer. The first metal layer is disposed on the substrate, and the second metal layer is disposed between the first metal layer and the second connecting layer. The density of the second metal layer is higher than that of the first metal layer.
3. The composite coating according to claim 2, characterized in that, The first metal layer has pores, and a portion of the metal in the second metal layer fills the pores of the first metal layer.
4. The composite coating according to claim 3, characterized in that, The material of the second connecting layer includes metals and metal compounds. The metals in the second connecting layer are of the same type as the metals in the second metal layer. The metal compounds include metal nitrides and / or metal carbides. Wherein, by mass percentage, the second connecting layer comprises: 30% to 70% of the metal compound and 30% to 70% of the metal; Alternatively, the material of the second connecting layer may further include a silicon-containing substance, which includes at least one of elemental silicon and silicon alloy. By mass percentage, the second connecting layer comprises: 30% to 70% of the metal compound and the silicon-containing substance, and 30% to 70% of the metal.
5. The composite coating according to claim 2, characterized in that, The thickness of the first metal layer is 50 nm to 100 nm; The thickness of the second metal layer is 150 nm to 250 nm; The thickness of the second connecting layer is 50nm to 100nm.
6. The composite coating according to claim 1, characterized in that, The silicon layer includes a first silicon layer disposed close to the substrate, a second silicon layer disposed away from the substrate, and a transition layer disposed between the first silicon layer and the second silicon layer, wherein the transition layer is a metal layer and / or a silicon alloy layer.
7. The composite coating according to claim 6, characterized in that, A first silicon layer, a transition layer, and a second silicon layer constitute a group of silicon layers. The composite coating includes several groups of silicon layers, wherein the first layer disposed outside the second connecting layer is the first silicon layer.
8. The composite coating according to claim 6, characterized in that, The thickness ratio of the first silicon layer to the transition layer is 1:1 to 10:1; The thickness ratio of the second silicon layer to the transition layer is 1:1 to 10:
1.
9. The composite coating according to claim 6, characterized in that, The thickness of the first silicon layer is 5 nm to 4000 nm; The thickness of the transition layer is 5 nm to 500 nm; The thickness of the second silicon layer is 5nm to 4000nm.
10. The composite coating according to claim 1, characterized in that, The composite coating further includes an ion bombardment layer disposed between the substrate and the connecting layer, the ion bombardment layer being configured to be formed by bombarding the substrate with positively charged metal ions.
11. The composite coating according to claim 10, characterized in that, The ion source of the positively charged metal ions includes at least one of Ni, Cr, Ti, Al, or stainless steel.
12. The composite coating according to any one of claims 1 to 11, characterized in that, The surface dyn value of the substrate is >32 dyn / cm; and / or, The substrate material includes at least one of metallic and non-metallic materials, wherein the metallic material includes at least one of aluminum, stainless steel, and copper, and the non-metallic material includes at least one of polyimide and polyetherimide; and / or, The metal in the first bonding layer includes at least one of Ni, Cr, Ti, Al, Cu, and stainless steel; and / or, The composite coating further includes a surface layer disposed on the side of the silicon layer facing away from the substrate; wherein the thickness of the surface layer is 200 nm to 500 nm; and / or, The surface layer is a metal layer or a silicon alloy layer; and / or, The silicon layer is either a silicon elemental layer or a mixture layer; wherein, when the silicon layer is a mixture layer, the material of the mixture layer includes silicon elemental and metallic elemental, and the mass percentage of silicon elemental in the mixture layer is greater than or equal to 50%.
13. A method for preparing a composite coating as described in any one of claims 1 to 12, characterized in that, The preparation method includes the following steps: The first connecting layer is prepared on the substrate; The second connection layer is fabricated on the first connection layer; The silicon layer is prepared on the second interconnect layer.
14. The preparation method according to claim 13, characterized in that, The step of preparing the first connecting layer on the substrate includes: preparing a first metal layer using a vacuum deposition method with an arc target, and preparing a second metal layer on the first metal layer using a column target.
15. The preparation method according to claim 13, characterized in that, The step of preparing the second connecting layer on the first connecting layer includes: introducing nitrogen and / or acetylene gas, and preparing the second connecting layer on the first connecting layer using a metal target; Alternatively, nitrogen and / or acetylene gas can be introduced, and the second interconnect layer can be fabricated on the first interconnect layer using a metal target and a silicon pillar target.
16. The preparation method according to claim 13, characterized in that, Prior to the step of preparing the first connecting layer on the substrate, the preparation method further includes: cleaning and heating the precursor substrate to remove the oxide layer, oil, and impurities from the precursor substrate; performing glow discharge cleaning on the precursor substrate to obtain the substrate; and / or, After the step of preparing the silicon layer on the second interconnect layer, the preparation method further includes: preparing the surface layer on the side of the silicon layer facing away from the substrate.
17. The preparation method according to claim 13, characterized in that, Before the step of preparing the first interconnect layer on the substrate, the preparation method further includes: depositing positively charged metal ions on the substrate and connecting a negative bias voltage on the substrate to accelerate the positively charged metal ions to bombard the surface of the substrate, thereby obtaining an ion bombardment layer.
18. An electronic product, characterized in that, The electronic product includes: a composite coating as described in any one of claims 1 to 12, or a composite coating prepared by the preparation method as described in any one of claims 13 to 17.