TWI551717B - Method for manufacturing diamond-like carbon film - Google Patents

Description

Method for manufacturing diamond-like carbon film

The present invention relates to a method of making a film, and more particularly to a method of making a diamond-like carbon (DLC) film.

The diamond-like carbon film is an amorphous carbon film having both SP ² bonding and SP ³ bonding, and has a high content of SP ³ bonding therein. Due to the high content of SP ³ bonds, diamond-like carbon films have many diamond-like properties such as high hardness, high Young's modulus, high electrical resistivity, high thermal conductivity, wide optical transmission range, chemical resistance and Good wear resistance and so on. Moreover, the diamond-like carbon film can be formed at a low temperature, which is much easier to obtain than diamond. In addition, in the mold application, because the diamond-like carbon film has low friction coefficient, high hardness and high flatness, it has advantages in preventing sticking to help demoulding and improving the life of the mold, and also makes the drill-like Carbon film has great application potential in the fields of optics, electronics and machinery.

Because if a carbon film is plated at a high substrate temperature, graphitization is liable to occur, and the hardness of the formed carbon film is greatly reduced. Therefore, when plating a carbon film, it is generally at normal temperature or low temperature (below normal temperature). Row. However, in general, a carbon film formed at normal temperature or low temperature is in the air, and at a temperature of about 350 ° C to 400 ° C, the diamond-like carbon film may deteriorate; in nitrogen, at about 550. At temperatures between °C and 600 °C, the diamond-like carbon film will also deteriorate. Therefore, for example, in a mold application, for a mold of a high-temperature molding process (for example, a process with a temperature of up to 700 ° C to 800 ° C), the diamond-like carbon film is greatly deteriorated due to the problem of high temperature deterioration, thereby reducing the diamond-like carbon. The applicability of the film.

At present, a diamond-like carbon film having a thermal stability of about 650 ° C to 700 ° C under air and a temperature of about 900 ° C to 1000 ° C under nitrogen has been developed. However, in these developed carbon films, the thermal stability of the diamond-like carbon film is increased, but the hardness is lowered. For example, the hardness of the original diamond-like carbon film can reach about 10GPa~25GPa, but the hardness of the newly developed diamond-like carbon film can only reach about 8GPa~15Gpa, which seriously affects its applicability.

In addition, since the diamond-like carbon film is currently grown at a lower film forming temperature such as normal temperature or low temperature, and the growth of the film layer coated with the high-temperature coating is required, for example, the coating temperature of the titanium nitride (TiN) layer needs to be more than 300. °C can make the titanium nitride layer have a good crystal form, and it is necessary to carry out the diamond-like carbon coating process after the substrate temperature is lowered to the normal temperature after the high-temperature coating process. However, in vacuum, it is quite time consuming to lower the substrate temperature to the growth temperature required for diamond-like carbon. Therefore, the diamond-like carbon coating process is difficult to integrate with other high-temperature coating processes, which affects the fluency of the overall coating process.

Accordingly, it is an object of the present invention to provide a method for producing a diamond-like carbon film which uses an aromatic ring hydrocarbon as a reaction precursor for a growth-like diamond carbon film. Since the aromatic ring hydrocarbon has a benzene ring structure, a diamond-like carbon film having a large sp ³ structure (diamond structure) content and a small sp ² structure (graphite structure) content can be obtained when growing at a high substrate temperature, and thus a material can be obtained. High-quality, high-quality diamond-like carbon film.

Another object of the present invention is to provide a method for producing a diamond-like carbon film, which has a high carbon-hydrogen ratio of an aromatic ring hydrocarbon used as a reaction precursor of a growth-type diamond carbon film, thereby effectively reducing diamond-like carbon The hydrogen content in the membrane.

Still another object of the present invention is to provide a method for producing a diamond-like carbon film which can grow a diamond-like carbon film having a low hydrogen content, thereby reducing the amount of hydrogen released by the diamond-like carbon film in a high temperature environment. However, it is less likely to cause graphitization and thus a decrease in hardness, and the problem of a decrease in hardness of a diamond-like carbon film in a high-temperature application environment can be greatly improved.

Still another object of the present invention is to provide a method for manufacturing a diamond-like carbon film which is formed by growing a diamond-like carbon film at a high substrate temperature, thereby being combined with other coating processes requiring temperature rise, thereby improving the efficiency of the overall coating process.

In accordance with the above object of the present invention, a method of manufacturing a diamond-like carbon film is provided which comprises the following steps. The substrate is placed in the reaction chamber. The aromatic ring hydrocarbon is introduced into the reaction chamber. A carbon-like carbon film is grown on the substrate by using an aromatic ring hydrocarbon as a reaction precursor, wherein the step of growing the carbon-like film comprises controlling the substrate temperature to 200 ° C to 800 ° C.

According to an embodiment of the present invention, the above aromatic ring hydrocarbon has a chemical formula of C _x H _y , wherein x is greater than or equal to y.

According to another embodiment of the present invention, the above aromatic ring hydrocarbon is a polycyclic aromatic hydrocarbon. In some examples, the polycyclic aromatic hydrocarbon may be naphthalene, phenanthrene, pyrene, fullerene, phenanthroline, phenanthridine. Or xanthene.

According to still another embodiment of the present invention, the above aromatic ring hydrocarbon is a monocyclic aromatic hydrocarbon. In some examples, the monocyclic aromatic hydrocarbon can be benzene or toluene.

According to still another embodiment of the present invention, before the step of growing the carbon-coated carbon film, the method for manufacturing the diamond-like carbon film further comprises introducing a hydrocarbon having no benzene ring into the reaction chamber, wherein the aromatic ring hydrocarbon is used. The total weight of the hydrocarbon having no benzene ring is 100, and the weight of the hydrocarbon having no benzene ring is less than or equal to 50.

According to still another embodiment of the present invention, the aromatic ring hydrocarbon contains the nitrogen element (N), the oxygen element (O) or the sulfur element (S), in the case of not including the hydrogen element in the aromatic ring hydrocarbon. The content of the carbon element in the aromatic ring hydrocarbon accounts for 80 at.% or more.

According to still another embodiment of the present invention, the step of growing the diamond-like carbon film comprises adding bismuth (Si), boron (B), aluminum (Al), titanium (Ti) (IVB), vanadium (V) (VB group) element, chromium (Cr) group (VIB group) element, sputum a compound, a boron compound, an aluminum compound, a titanium group (IVB group) compound, a vanadium group (VB group) compound, and/or a chromium group (VIB group) compound.

According to still another embodiment of the present invention, the step of growing the diamond-like carbon film comprises using a physical vapor deposition (PVD) method or a plasma-enhanced chemical vapor deposition (PECVD) method. , filtered cathodic arc deposition method, electron cyclone resonance microwave plasma method, sputtering method, ion plating method or cathodic arc deposition (cathodic) Arc deposition method.

100‧‧‧Drilling carbon film

102‧‧‧Reaction room

104‧‧‧heater

106‧‧‧lower electrode

108‧‧‧Substrate

110‧‧‧Aromatic ring hydrocarbons

112‧‧‧Transportation line

200‧‧‧ steps

202‧‧‧Steps

204‧‧‧Steps

The above and other objects, features, advantages and embodiments of the present invention will become more <RTIgt; <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; A schematic diagram of a device for a membrane; and [Fig. 2] is a flow chart showing a method of manufacturing a diamond-like carbon film in accordance with an embodiment of the present invention.

In view of the fact that the conventional diamond-like carbon film cannot grow at a high temperature, and in a high-temperature application environment, it will deteriorate and the hardness is greatly reduced, thereby severely limiting the application of the diamond-like carbon film. Therefore, the present invention proposes a method for producing a diamond-like carbon film by using an aromatic ring hydrocarbon as a precursor for the growth of a diamond-like carbon film, and a diamond-like carbon film can be grown at a high substrate temperature. The aromatic ring hydrocarbon has a high carbon-hydrogen ratio and a benzene ring structure, and can still obtain less hydrogen when grown at a high substrate temperature, and has a sp ³ structure (diamond structure) content and a sp ² structure (graphite structure) content. Less high hardness diamond-like carbon film. Moreover, since the hydrogen content in the diamond-like carbon film is small, the amount of hydrogen released by the diamond-like carbon film in a high temperature environment can be greatly reduced, and the graphitization phenomenon and the hardness caused by the high temperature environment are less likely to occur. It is reduced, so it can effectively maintain the hardness of the diamond-like carbon film under high temperature application environment, and the temperature resistance is excellent. In addition, the method of the present invention grows a diamond-like carbon film in a heating process environment, so that the growth process of the diamond-like carbon film can be combined with other coating processes that require heating.

1 and FIG. 2, wherein FIG. 1 is a schematic diagram of a device for growing a diamond-like carbon film according to an embodiment of the present invention, and FIG. 2 is a view showing a diamond-like carbon according to an embodiment of the present invention. A flow chart of a method of manufacturing a film. In one embodiment of the present invention, the diamond-like carbon film 100 can be produced in the reaction chamber 102 as shown in FIG. For example, the reaction chamber 102 can be a plasma-assisted chemical vapor deposition reaction chamber, and the reaction chamber 102 is provided with a heater 104 and a lower electrode 106, wherein the heater 104 and the lower electrode 106 are opposed to each other.

In some examples, as shown in FIG. 1 and FIG. 2, when the diamond-like carbon film 100 is grown in the reaction chamber 102, step 200 may be performed first to load the substrate 108 to be subjected to a diamond-like carbon coating operation. In chamber 102, and the substrate 108 is placed on the lower electrode 106. The substrate 108 can be a general workpiece, such as a component of a conventional processing tool or a mold of a molding apparatus.

Next, step 202 can be performed to introduce the aromatic ring hydrocarbon 110 into the reaction chamber 102 through the transfer line 112. In some examples, the aromatic ring hydrocarbon 110 has the chemical formula C _x H _y , where x is greater than or equal to y. That is, in the aromatic ring hydrocarbon 110, the amount of carbon elements is greater than or equal to the number of hydrogen elements. Further, the aromatic ring hydrocarbon 110 may be a monocyclic aromatic hydrocarbon such as benzene or toluene. The aromatic ring hydrocarbon 110 may also be a polycyclic aromatic hydrocarbon such as naphthalene, phenanthrene, pyrene or fullerene having a chemical formula of C _x H _y or the like, or Phenanthroline, phenanthridine or xanthene which are composed of not only carbon and hydrogen but also other elements.

In some exemplary examples, the aromatic ring hydrocarbon 110 may contain, for example, a nitrogen element, an oxygen element, or a sulfur element in addition to a carbon element and a hydrogen element. In such an exemplary example, in the case where the hydrogen element in the aromatic ring hydrocarbon 110 is not included, the content of the carbon element in the aromatic ring hydrocarbon 110 accounts for carbon and other elements (i.e., nitrogen element, oxygen element or sulfur). The total content of the element) is 80 at.% or more.

Alternatively, hydrocarbons having no benzene ring may be additionally introduced into the reaction chamber 102 before the growth of the diamond-like carbon film 100 has begun. In such an example, the total weight of the aromatic ring hydrocarbon introduced into the reaction chamber 102 and the hydrocarbon having no benzene ring is 100, and the benzene ring is not included. The hydrocarbon weight fraction is less than or equal to 50. That is, the aromatic ring hydrocarbon 110 is the main reaction precursor, and the hydrocarbon having no benzene ring is an additional added reactant, so the hydrocarbon having no benzene ring is added in an amount not exceeding the aromatic ring hydrocarbon. The amount of compound 110 introduced.

After the plating material such as the aromatic ring hydrocarbon 110 is introduced into the reaction chamber 102, the step 204 is carried out, and a hydrocarbon such as the aromatic ring hydrocarbon 110 is used as a reaction precursor, and the process temperature is raised to grow on the substrate 108. The carbon film 100 is drilled. In some examples, a general physical vapor deposition method or a general chemical vapor deposition method may be employed in the step of growing the diamond-like carbon film 100. Alternatively, a general physical vapor deposition method, such as sputtering, or a general chemical vapor deposition method, such as plasma-assisted chemical vapor deposition, filtered cathodic arc deposition, electron cyclotron resonance, may be employed. Microwave plasma method, ion coating method or cathodic arc deposition method.

In some examples, when the step of growing the diamond-like carbon film 100 is performed, the substrate temperature of the green diamond-like carbon film 100 can be controlled to be 200 ° C to 800 ° C. In some specific examples, when the aromatic ring hydrocarbon 110 is a polycyclic aromatic hydrocarbon such as naphthalene, phenanthrene, anthracene, fullerene, phenanthroline, phenanthridine or xanthene, The step of drilling the carbon film 100 can control the substrate temperature from 25 ° C to 800 ° C, preferably from 100 ° C to 800 ° C, and more preferably from 200 ° C to 800 ° C.

When the carbon film 100 is drilled, since the aromatic ring hydrocarbon 110 used has a stable benzene ring structure, a sp ³ structure (diamond structure) content and a sp ² structure can be obtained when growing at a high substrate temperature ( The high hardness diamond-like carbon film 100 with a small amount of graphite structure can effectively ensure the quality of the diamond-like carbon film 100. Further, since the aromatic ring hydrocarbon 110 has a high carbon-hydrogen ratio, the amount of hydrogen in the drilled carbon film 100 grown is small. Since the diamond carbon film 100 grown has not only a sp ³ structure (diamond structure) content but also a sp ² structure (graphite structure) content and a low hydrogen content, it can be released from the diamond-like carbon film 100 in a high temperature environment. The amount of hydrogen is very rare, and the graphitization of the diamond-like carbon film 100 can be effectively avoided, thereby maintaining the hardness of the diamond-like carbon film 100 in a high temperature application environment. Therefore, the temperature resistance and hardness of the diamond-like carbon film 100 can be improved. In addition, since the diamond-like carbon film 100 is grown at a high substrate temperature, the time for lowering the process temperature to the growth temperature required for the diamond-like carbon film 100 after other high-temperature coating or coating process requiring temperature rise is compared with the conventional one. The room temperature coating process for diamond-like carbon can be shortened a lot. Therefore, the growth process of the diamond-like carbon film 100 can be effectively integrated with other coating processes that require temperature rise, thereby improving the efficiency of the overall coating process.

Optionally, in the process of growing the diamond-like carbon film 100, bismuth, boron, aluminum, titanium (IVB group) elements, vanadium (VB group) elements, chromium group (VIB group) elements, bismuth compounds may be additionally added. a boron compound, an aluminum compound, a titanium group (IVB group) compound, a vanadium group (VB group) compound, and/or a chromium group (VIB group) compound, thereby improving the toughness or reduction of the grown carbon film 100. The stress of the carbon film 100 is drilled.

Three exemplary embodiments are set forth below to illustrate that the drilling of a carbon film with an aromatic compound at a high substrate temperature, for example, greater than 200 ° C, can increase the hardness of the diamond-like carbon film and reduce the compressive stress.

In the first exemplary embodiment, 304 stainless steel having a suitable size of a titanium metal film is used as a substrate test piece for a plated diamond-like carbon film. The contaminants on the surface of the substrate test piece were washed with acetone, alcohol and deionized water, respectively, by ultrasonic cleaning, and the substrate test piece was blown dry with nitrogen. Next, the substrate test piece is fixed to the electrode of the vacuum chamber. Subsequently, the vacuum chamber is evacuated with a vacuum pump until the pressure in the vacuum chamber is about 3 x 10 ^-5 torr. Next, argon gas and hydrogen gas are introduced into the vacuum chamber, and a power source is applied by the RF power supply to generate argon and hydrogen mixed plasma to clean the surface of the substrate test piece, and the bias voltage of the substrate test piece is controlled at this time. About 650V~700V, and the temperature of the stainless steel substrate in the vacuum chamber is raised to 500 °C ~ 600 °C. After that, the toluene was introduced into the vacuum chamber, and the argon gas and the hydrogen gas were turned off, and the pressure in the vacuum chamber was controlled to be 1.5×10 ⁻² Torr, and the diamond-like carbon film was plated on the surface of the substrate test piece. The bias of the substrate test piece is controlled at about 650V. After the coating of such a carbon film is completed, the film thickness of the diamond-like carbon film is measured by a surface roughness meter. Combined with the calculation formula to calculate the stress of such a carbon film, the stress of such a carbon film can be obtained to be about 2.91 GPa. In addition, the hardness of such a drilled carbon film was measured by a nanoindenter to obtain a hardness of about 37.6 GPa.

In a second exemplary embodiment, a single-sided polished 4 wafer is cut to size to serve as a substrate test for a diamond-coated carbon film. The substrate test piece is first cleaned using a cleaning method as in the first exemplary embodiment. Next, the substrate test piece is fixed to the electrode of the vacuum chamber. Subsequently, the vacuum chamber is evacuated with a vacuum pump until the pressure in the vacuum chamber is about 3 x 10 ^-5 torr. Next, argon gas and hydrogen gas are introduced into the vacuum chamber, and a power source is applied by the RF power supply to generate argon and hydrogen mixed plasma to clean the surface of the substrate test piece, and the bias voltage of the substrate test piece is controlled at this time. About 650V~700V, and simultaneously raise the temperature of the wafer substrate in the vacuum chamber to 550 ° C ~ 650 ° C. Thereafter, naphthalene is introduced into the vacuum chamber, and argon gas and hydrogen gas are turned off, and the pressure in the vacuum chamber is controlled to be 1.5×10 ⁻² Torr, and the surface of the substrate test piece is plated with diamond-like carbon. The film, at this time, the bias of the substrate test piece was controlled at about 700V. After the coating of such a carbon film is completed, the film thickness of the diamond-like carbon film is measured by a surface roughness meter. Combined with the calculation formula to calculate the stress of such a carbon film, the stress of such a carbon film can be obtained to be about 3.26 GPa. In addition, the hardness of such a drilled carbon film was measured by a nanoindenter to obtain a hardness of about 41.5 GPa.

In a third exemplary embodiment, a single-sided polished 4 inch wafer is cut to an appropriate size for use as a substrate test strip for a diamond-coated carbon film. The substrate test piece is first cleaned using a cleaning method as in the first exemplary embodiment. Next, the substrate test piece is fixed to the electrode of the vacuum chamber. Subsequently, the vacuum chamber is evacuated with a vacuum pump until the pressure in the vacuum chamber is about 3 x 10 ^-5 torr. Next, argon gas and hydrogen gas are introduced into the vacuum chamber, and a power source is applied by the RF power supply to generate argon and hydrogen mixed plasma to clean the surface of the substrate test piece, and the bias voltage of the substrate test piece is controlled at this time. About 650V~700V, and simultaneously raise the temperature of the wafer substrate in the vacuum chamber to 200 °C ~ 250 °C. Thereafter, benzene is introduced into the vacuum chamber, and argon gas and hydrogen gas are turned off, and the pressure in the vacuum chamber is controlled to be 4.0×10 ⁻² Torr, and the surface of the substrate test piece is plated with diamond-like carbon. The film, at this time, the bias of the substrate test piece was controlled at about 550V. After the coating of such a carbon film is completed, the film thickness of the diamond-like carbon film is measured by a surface roughness meter. Combined with the calculation formula to calculate the stress of such a carbon film, the stress of such a carbon film can be obtained to be about 2.6 GPa. In addition, the hardness of such a drilled carbon film was measured by a nanoindenter to obtain a hardness of about 32.6 GPa.

The hardness of the conventional carbon-containing carbon film is only about 10 GPa to 25 GPa and the stress is about 5 GPa or more, and the hardness of the carbon film produced by the embodiment of the present invention can reach 30 GPa or more, or even 45 GPa to 50 GPa or Higher, and the stress can be lower than 4GPa. It can be seen that the application of the embodiment of the present invention can indeed improve the hardness of the diamond-like carbon film and reduce the compressive stress.

As apparent from the above embodiments, one of the advantages of the present invention is that the method for producing a carbon-impregnated carbon film of the present invention uses an aromatic ring hydrocarbon as a reaction precursor of a growing diamond-like carbon film. Since the aromatic ring hydrocarbon has a benzene ring structure, a diamond-like carbon film having a large sp ³ structure (diamond structure) content and a small sp ² structure (graphite structure) content can be obtained when growing at a high substrate temperature, and thus a material can be obtained. High-quality, high-quality diamond-like carbon film.

According to the above-described embodiment, another advantage of the present invention is that the aromatic hydrocarbon hydrocarbon having a high efficiency as a reaction precursor of a growth-like diamond carbon film is used because the method for producing a carbon-coated carbon film of the present invention has a high carbon-hydrogen ratio. Therefore, the hydrogen content in the diamond-like carbon film can be effectively reduced.

According to the above embodiments, another advantage of the present invention is that the method for manufacturing a carbon film of the present invention can grow a diamond-like carbon film with a low hydrogen content, thereby reducing the release of the diamond-like carbon film in a high temperature environment. The amount of hydrogen produced is less prone to graphitization and the resulting hardness is reduced, which in turn greatly improves the hardness of the diamond-like carbon film in high temperature applications.

According to the above embodiments, another advantage of the present invention is that the method for manufacturing the carbon film of the present invention is to grow a diamond-like carbon film at a high substrate temperature, so that it can be combined with other coating processes requiring temperature rise, and can be improved. The efficiency of the overall coating process.

While the present invention has been described above by way of example, it is not intended to be construed as a limitation of the scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

200‧‧‧ steps

202‧‧‧Steps

204‧‧‧Steps

Claims (8)

A method for manufacturing a diamond-like carbon film, comprising: placing a substrate into a reaction chamber; introducing an aromatic ring hydrocarbon into the reaction chamber; and using the aromatic ring hydrocarbon as a reaction precursor, A type of drill carbon film is grown on the substrate, and the step of growing the carbon film is controlled to control a substrate temperature between 200 ° C and 800 ° C. The method for producing a carbon-drilled film according to the first aspect of the invention, wherein the aromatic ring hydrocarbon has a chemical formula of C _x H _y , wherein x is greater than or equal to y. The method for producing a carbon-drilled film according to the first aspect of the invention, wherein the aromatic ring hydrocarbon is a polycyclic aromatic hydrocarbon. The method for producing a carbon-drilled film according to claim 3, wherein the aromatic ring hydrocarbon is a monocyclic aromatic hydrocarbon. The method for manufacturing a carbon-coated carbon film according to the first aspect of the patent application, before the step of growing the carbon-coated carbon film, further comprises introducing a hydrocarbon having no benzene ring into the reaction chamber, wherein the aromatic ring is introduced The total weight of the hydrocarbon and the hydrocarbon having no benzene ring is 100, and the weight of the hydrocarbon having no benzene ring is less than or equal to 50. The method for producing a carbon-coated carbon film according to the first aspect of the invention, wherein the aromatic ring hydrocarbon contains a nitrogen element, an oxygen element or a sulfur element, excluding the hydrogen element in the aromatic ring hydrocarbon, The content of the carbon element in the aromatic ring hydrocarbon is 80 at.% or more. The method for manufacturing a carbon film according to the first aspect of the patent application, wherein the step of growing the carbon film comprises adding lanthanum, boron, aluminum, titanium (IVB group) elements, vanadium group (VB group) elements, chromium Group (Group VIB) element, bismuth compound, boron compound, aluminum compound, titanium group (IVB group) compound, vanadium group (VB group) compound and/or chromium group (VIB group) compound. The method for manufacturing a carbon-coated carbon film according to claim 1, wherein the step of growing the carbon-coated carbon film comprises using a physical vapor deposition method, a plasma-assisted chemical vapor deposition method, and a filtered cathode arc deposition method. Method, an electron cyclotron resonance microwave plasma method, a sputtering method, an ion coating method or a cathodic arc deposition method.