A method for producing a low-stress DLC film

Abstract

This invention discloses a method for preparing a low-stress DLC film, comprising: pretreating the surface of a substrate; depositing a silicon nitride film on the surface of the pretreated substrate using magnetron sputtering; depositing a DLC sample film on the surface of the silicon nitride film; bombarding the surface of the DLC sample film with an ion beam and performing plasma-enhanced chemical vapor deposition to deposit a low-stress DLC film on the surface of the silicon nitride film; and performing post-treatment on the low-stress DLC film. The technical solution of this invention enables the preparation of DLC films with low stress, thereby ensuring the stable quality of the DLC film and making it suitable for large-scale preparation.

Description

Technical Field

[0001] This invention relates to the field of thin film preparation technology, and in particular to a method for preparing a low-stress DLC film. Background Technology

[0002] DLC (Diamond-like Carbon) film is a special type of thin film with excellent friction properties, chemical stability, biocompatibility, hardness, and low coefficient of friction. It is widely used in various fields such as aerospace, automotive, medical devices, and semiconductors.

[0003] However, there are still some problems in the preparation of DLC films. For example, stress instability is prone to occur during the preparation process, which leads to unstable quality of DLC films and is not conducive to large-scale production. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing low-stress DLC films, which enables the preparation of DLC films under low stress, thereby ensuring the quality stability of the DLC films and making them suitable for large-scale preparation.

[0005] To achieve the above objectives, embodiments of the present invention provide a method for preparing a low-stress DLC film, comprising:

[0006] The surface of the substrate is pretreated;

[0007] A silicon nitride film was deposited on the surface of a pretreated substrate using magnetron sputtering.

[0008] A DLC sample film is deposited on the surface of the silicon nitride film;

[0009] The surface of the DLC sample film was bombarded with an ion beam and plasma-enhanced chemical vapor deposition was performed to deposit a low-stress DLC film on the surface of the silicon nitride film.

[0010] The low-stress DLC film is then post-processed.

[0011] Furthermore, the pretreatment of the substrate surface specifically includes:

[0012] The surface of the substrate must be cleaned, degreased, and dusted at least.

[0013] Furthermore, the thickness of the silicon nitride film is 100 nm to 1 μm.

[0014] Furthermore, the thickness of the DLC sample film is 1–5 nm.

[0015] Furthermore, the energy of the ion beam is 100–400 eV.

[0016] Furthermore, the deposition source for the plasma-enhanced chemical vapor deposition is a hydrocarbon gas, which is at least one of C2H6 and CH4.

[0017] Furthermore, the process parameters for the plasma-enhanced chemical vapor deposition include a gas pressure of 70–75 Pa.

[0018] Furthermore, the post-processing of the low-stress DLC film specifically includes:

[0019] The low-stress DLC film shall be subjected to at least annealing and polishing.

[0020] Furthermore, the annealing temperature is 600–800℃.

[0021] Furthermore, the polishing speed is 50-60 rpm, and the polishing time is 3 hours.

[0022] Compared with existing technologies, this invention provides a method for preparing a low-stress DLC film. First, the surface of a substrate is pretreated. Then, a silicon nitride film is deposited on the pretreated substrate surface using magnetron sputtering. Next, a DLC sample film is deposited on the silicon nitride film surface. Then, the surface of the DLC sample film is bombarded with an ion beam, followed by plasma-enhanced chemical vapor deposition to deposit a low-stress DLC film on the silicon nitride film surface. Finally, the low-stress DLC film undergoes post-processing. This invention enables the preparation of DLC films with low stress, thereby ensuring stable DLC film quality and making it suitable for large-scale production. Attached Figure Description

[0023] Figure 1 This is a flowchart of a preferred embodiment of a method for preparing a low-stress DLC film provided by the present invention. Detailed Implementation

[0024] 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.

[0025] This invention provides a method for preparing a low-stress DLC film, see [link to relevant documentation]. Figure 1 The diagram shown is a flowchart of a preferred embodiment of a method for preparing a low-stress DLC film provided by the present invention, the method comprising steps S11 to S15:

[0026] Step S11: Pre-treat the surface of the substrate;

[0027] Step S12: Deposit a silicon nitride film on the surface of the pretreated substrate using magnetron sputtering.

[0028] Step S13: Deposit a DLC sample film on the surface of the silicon nitride film;

[0029] Step S14: Use an ion beam to bombard the surface of the DLC sample film and perform plasma-enhanced chemical vapor deposition to deposit a low-stress DLC film on the surface of the silicon nitride film.

[0030] Step S15: Post-process the low-stress DLC film.

[0031] In practice, firstly, a substrate is provided for fabricating a low-stress DLC film on its surface. The surface of the substrate is pretreated to improve the adhesion between the subsequently deposited silicon nitride film and the substrate surface. Then, a silicon nitride film is deposited on the pretreated substrate surface using magnetron sputtering as a deposition layer. Next, a thin DLC sample film is deposited on the surface of the silicon nitride film as a growth nucleus for the subsequent deposition of the low-stress DLC film. Then, the substrate with the silicon nitride film and the DLC sample film deposited on its surface is placed in an ion source region, and the surface of the DLC sample film is bombarded with an ion beam and subjected to plasma-enhanced chemical vapor deposition to deposit a low-stress DLC film on the surface of the silicon nitride film. Finally, the low-stress DLC film is post-treated.

[0032] Understandably, when performing step S14, if the DLC sample film reacts completely and there is no residue, a DLC film (i.e., a low-stress DLC film) will eventually be formed on the surface of the silicon nitride film. If the DLC sample film does not react completely and there is residue, two DLC films will eventually be formed on the surface of the silicon nitride film (i.e., a DLC sample film and a low-stress DLC film, meaning that there is a residual DLC sample film between the silicon nitride film and the low-stress DLC film).

[0033] It should be noted that, in the embodiments of the present invention, by using a silicon nitride film as the deposition layer, the bonding ability of the low-stress DLC film can be improved; by using a DLC sample film as the growth core of the low-stress DLC film, a uniform and dense low-stress DLC film can be formed; by using ion beam bombardment and plasma-enhanced chemical vapor deposition, low-stress DLC film preparation (i.e., obtaining a low-stress DLC film) can be achieved; and by performing post-processing on the low-stress DLC film, the performance of the low-stress DLC film can be further optimized.

[0034] In one optional embodiment, the pretreatment of the substrate surface specifically includes:

[0035] The surface of the substrate must be cleaned, degreased, and dusted at least.

[0036] Specifically, in conjunction with the above embodiments, when pre-treating the surface of the substrate, the present invention can perform cleaning, degreasing, and dust removal on the surface of the substrate to improve the adhesion between the subsequently deposited silicon nitride film and the substrate surface.

[0037] In one optional embodiment, the thickness of the silicon nitride film is 100 nm to 1 μm.

[0038] Specifically, in conjunction with the above embodiments, the thickness of the silicon nitride film deposited on the surface of the pretreated substrate by magnetron sputtering in this embodiment of the invention is between 100 nanometers and 1 micrometer.

[0039] For example, the thickness of the silicon nitride film can be 100 nanometers, 200 nanometers, 300 nanometers, 400 nanometers, 500 nanometers, 600 nanometers, 700 nanometers, 800 nanometers, 900 nanometers or 1000 nanometers (i.e. 1 micrometer), and can also be set according to actual needs. The embodiments of the present invention do not make specific limitations.

[0040] In one optional embodiment, the thickness of the DLC sample film is 1–5 nm.

[0041] Specifically, in conjunction with the above embodiments, the thickness of the DLC sample film deposited on the surface of the silicon nitride film in the embodiments of the present invention is between 1 nanometer and 5 nanometers. That is, the embodiments of the present invention can deposit a DLC sample film with a thickness of 1 nanometer to 5 nanometers on the surface of the silicon nitride film as a growth core for subsequent deposition of low-stress DLC film.

[0042] For example, the thickness of the DLC sample film can be 1 nanometer, 2 nanometers, 3 nanometers, 4 nanometers or 5 nanometers, and can also be set according to actual needs. This embodiment of the invention does not make specific limitations.

[0043] In one alternative embodiment, the energy of the ion beam is 100–400 eV.

[0044] Specifically, in conjunction with the above embodiments, when using an ion beam to bombard the surface of a DLC sample film, the energy of the ion beam is between 100 eV and 400 eV.

[0045] For example, the energy of the ion beam can be 100eV, 150eV, 200eV, 250eV, 300eV, 350eV or 400eV, and can also be set according to actual needs. This embodiment of the invention does not make specific limitations.

[0046] In one optional embodiment, the deposition source for the plasma-enhanced chemical vapor deposition is a hydrocarbon gas, which is at least one of C2H6 and CH4.

[0047] Specifically, in conjunction with the above embodiments, the deposition source used in the plasma-enhanced chemical vapor deposition of the present invention is hydrocarbon gas, and the hydrocarbon gas can be selected from gases containing hydrocarbons such as C2H6 or CH4.

[0048] In one optional embodiment, the process parameters for the plasma-enhanced chemical vapor deposition include a gas pressure of 70–75 Pa.

[0049] Specifically, in conjunction with the above embodiments, the gas pressure in the plasma-enhanced chemical vapor deposition (PECVD) of the present invention is generally around 70 Pa to 75 Pa.

[0050] For example, the gas pressure for plasma-enhanced chemical vapor deposition can be 70 Pa, 71 Pa, 72 Pa, 73 Pa, 74 Pa or 75 Pa, and can also be set according to actual needs. This embodiment of the invention does not make specific limitations.

[0051] In one optional embodiment, the post-processing of the low-stress DLC film specifically includes:

[0052] The low-stress DLC film shall be subjected to at least annealing and polishing.

[0053] Specifically, in conjunction with the above embodiments, the present invention can perform annealing and polishing on the low-stress DLC film during post-processing.

[0054] It should be noted that the embodiments of the present invention can further optimize the performance of low-stress DLC films by using post-processing methods such as annealing and polishing.

[0055] In one alternative embodiment, the annealing temperature is 600–800°C.

[0056] Specifically, in conjunction with the above embodiments, the annealing temperature of the low-stress DLC film in this embodiment of the invention is between 600°C and 800°C.

[0057] For example, the annealing temperature can be 600℃, 610℃, 620℃, 630℃, 640℃, 650℃, 660℃, 670℃, 680℃, 690℃, 700℃, 710℃, 720℃, 730℃, 740℃, 750℃, 760℃, 770℃, 780℃, 790℃, or 800℃, and can also be set according to actual needs. This embodiment of the invention does not impose specific limitations.

[0058] In one alternative embodiment, the polishing speed is 50-60 rpm and the polishing time is 3 hours.

[0059] Specifically, in conjunction with the above embodiments, when polishing the low-stress DLC film, the polishing speed is between 50 rpm and 60 rpm, and the polishing time is 3 hours.

[0060] For example, the polishing speed can be 50rpm, 51rpm, 52rpm, 53rpm, 54rpm, 55rpm, 56rpm, 57rpm, 58rpm, 59rpm or 60rpm, and can also be set according to actual needs. This embodiment of the invention does not make specific limitations.

[0061] Based on all the above embodiments, the implementation process of this solution is described below through the first specific embodiment, including: (1) providing a substrate and cleaning, degreasing and dust removal of the surface of the substrate to improve the bonding ability between the subsequently deposited silicon nitride film and the substrate surface; (2) depositing a silicon nitride film with a thickness of 100 nm on the surface of the pretreated substrate using magnetron sputtering as a deposition layer; (3) depositing a DLC sample film with a thickness of 1 nm on the surface of the silicon nitride film as a growth core for the subsequent deposition of a low-stress DLC film; (4) depositing a silicon nitride sample film with a thickness of 1 nm on the surface of the silicon nitride film as a growth core for the subsequent deposition of a low-stress DLC film; The substrates of the silicon film and the DLC sample film are placed in the ion source area. The surface of the DLC sample film is bombarded with an ion beam with an energy of 100eV. C2H6 or CH4 hydrocarbon gas is used as the deposition source. Plasma-enhanced chemical vapor deposition is performed under process parameters of 70Pa pressure to deposit a low-stress DLC film on the surface of the silicon nitride film. (5) The low-stress DLC film is annealed and polished. The annealing temperature is 600℃, the polishing speed is 50rpm, and the polishing time is 3 hours to further optimize the performance of the low-stress DLC film.

[0062] Based on all the above embodiments, the implementation process of this solution is described below through a second specific embodiment, including: (1) providing a substrate and cleaning, degreasing and dust removal of the surface of the substrate to improve the bonding ability between the subsequently deposited silicon nitride film and the substrate surface; (2) depositing a silicon nitride film with a thickness of 550 nm on the surface of the pretreated substrate using magnetron sputtering as a deposition layer; (3) depositing a DLC sample film with a thickness of 3 nm on the surface of the silicon nitride film as a growth core for subsequent deposition of low-stress DLC film; (4) depositing a silicon nitride film with a thickness of 3 nm on the surface of the silicon nitride film as a growth core for subsequent deposition of low-stress DLC film; The substrates of the silicon film and the DLC sample film are placed in the ion source area. The surface of the DLC sample film is bombarded with an ion beam with an energy of 250eV. C2H6 or CH4 hydrocarbon gas is used as the deposition source. Plasma-enhanced chemical vapor deposition is performed under process parameters of 72Pa pressure to deposit a low-stress DLC film on the surface of the silicon nitride film. (5) The low-stress DLC film is annealed and polished. The annealing temperature is 700℃, the polishing speed is 55rpm, and the polishing time is 3 hours to further optimize the performance of the low-stress DLC film.

[0063] Based on all the above embodiments, the implementation process of this solution is described below through a third specific embodiment, including: (1) providing a substrate and cleaning, degreasing and dust removal of the surface of the substrate to improve the bonding ability between the subsequently deposited silicon nitride film and the substrate surface; (2) depositing a silicon nitride film with a thickness of 1 μm on the surface of the pretreated substrate using magnetron sputtering as a deposition layer; (3) depositing a DLC sample film with a thickness of 5 nm on the surface of the silicon nitride film as a growth core for the subsequent deposition of a low-stress DLC film; (4) depositing a silicon nitride sample film on the surface of the substrate. The substrates of the film and the DLC sample film are placed in the ion source area. The surface of the DLC sample film is bombarded with an ion beam with an energy of 400 eV. C2H6 or CH4 hydrocarbon gas is used as the deposition source. Plasma-enhanced chemical vapor deposition is performed under process parameters of 75 Pa pressure to deposit a low-stress DLC film on the surface of the silicon nitride film. (5) The low-stress DLC film is annealed and polished. The annealing temperature is 800℃, the polishing speed is 60 rpm, and the polishing time is 3 hours to further optimize the performance of the low-stress DLC film.

[0064] In summary, the method for preparing a low-stress DLC film provided by this invention involves: first, pretreating the surface of a substrate; then, depositing a silicon nitride film on the pretreated substrate surface using magnetron sputtering; next, depositing a DLC sample film on the surface of the silicon nitride film; then, bombarding the surface of the DLC sample film with an ion beam and performing plasma-enhanced chemical vapor deposition to deposit a low-stress DLC film on the surface of the silicon nitride film; and finally, post-processing the low-stress DLC film. This invention, by using a silicon nitride film as the deposition layer and a DLC sample film as the growth core of the low-stress DLC film, and employing ion beam bombardment and plasma-enhanced chemical vapor deposition, enables the low-stress preparation of DLC films. The post-processing method further optimizes the performance of the low-stress DLC film, ensuring its quality stability. In addition to the quality stability of the low-stress DLC film, this invention also has advantages such as simple preparation method and low cost, making it suitable for large-scale preparation.

[0065] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a low-stress DLC film, characterized in that, include: The surface of the substrate is pretreated; A silicon nitride film was deposited on the surface of a pretreated substrate using magnetron sputtering. A DLC sample film is deposited on the surface of the silicon nitride film; The surface of the DLC sample film was bombarded with an ion beam and plasma-enhanced chemical vapor deposition was performed to deposit a low-stress DLC film on the surface of the silicon nitride film. The low-stress DLC film is then post-processed.

2. The method for preparing a low-stress DLC film as described in claim 1, characterized in that, The pretreatment of the substrate surface specifically includes: The surface of the substrate must be cleaned, degreased, and dusted at least.

3. The method for preparing a low-stress DLC film as described in claim 1, characterized in that, The thickness of the silicon nitride film is 100 nm to 1 μm.

4. The method for preparing a low-stress DLC film as described in claim 1, characterized in that, The thickness of the DLC sample film is 1–5 nm.

5. The method for preparing a low-stress DLC film as described in claim 1, characterized in that, The energy of the ion beam is 100–400 eV.

6. The method for preparing a low-stress DLC film as described in claim 1, characterized in that, The deposition source for the plasma-enhanced chemical vapor deposition is a hydrocarbon gas, which is at least one of C2H6 and CH4.

7. The method for preparing a low-stress DLC film as described in claim 6, characterized in that, The process parameters for plasma-enhanced chemical vapor deposition include a gas pressure of 70–75 Pa.

8. The method for preparing a low-stress DLC film as described in claim 1, characterized in that, The post-processing of the low-stress DLC film specifically includes: The low-stress DLC film shall be subjected to at least annealing and polishing.

9. The method for preparing a low-stress DLC film as described in claim 8, characterized in that, The annealing temperature is 600–800℃.

10. The method for preparing a low-stress DLC film as described in claim 8, characterized in that, The polishing speed is 50-60 rpm, and the polishing time is 3 hours.

Images