Diamond-like carbon film coating apparatus

Abstract

A diamond-like carbon film coating apparatus comprises a chamber installed on a chamber support, a chamber door which can be opened and closed repeatedly, a pump installed at the back of the chamber to supply gas for coating the diamond-like carbon film onto a workpiece, and a workpiece support provided inside the chamber at the lower side and connected to a rotation control assembly, which is installed on the chamber support to support and enable the rotational movement of the workpiece. The workpiece support comprises a central axis, whose upper end has an electrode installed thereon and whose lower end penetrates into a receiving base and is connected to the rotation control assembly to rotate the receiving base to move around the central axis. The electrode is connected to an end of a rotational axis, wherein the rotational axis has a supporting base for supporting the workpiece and the other end of the rotational axis penetrates into the receiving base and is connected to the rotation control assembly to rotate the supporting base to move around the rotational axis.

Description

[0001] DIAMOND-LIKE CARBON FILM COATING APPARATUS

[0002] TECHNICAL FIELD

[0003] Engineering related to a diamond-like carbon film coating apparatus

[0004] BACKGROUND OF THE INVENTION

[0005] Diamond-like carbon film (DLC) has remarkable characteristics, such as hardness, ability to prevent gas permeation, high corrosion resistance, high frictional resistance, chemical inertness, and high biocompatibility without causing toxicity to the human body or the environment. It is used to coat the metal surface in various industrial applications, such as automobile parts industry, electronics industry, metal surface coating industry, food packaging industry, and medical materials. The chemical structures of the diamond-like carbon film can be classified into four groups: (1) tetrahedral amorphous carbon (to-C), (2) tetrahedral hydrogenated amorphous carbon (ta-C:H), (3) amorphous carbon (a-C), and (4) hydrogenated amorphous carbon (a-C:H), respectively. These chemical structures are formed by sp, sp2, and sp3hybridizations between carbons which affect the film properties. The film properties also depend on various factors, i.e., synthesis method, ingredients, temperature, coating duration, and coating equipment or apparatus. Different film synthesis methods can also result in different chemical structures of the film.

[0006] Diamond-like carbon film coating equipment or apparatuses are mentioned in some prior art references concerning elements or components that affect coating efficiency. Examples include the following:

[0007] US 20140342029 Al, titled “ROLLER DIE AND A METHOD FOR MANUFACTURING THE ROLLER DIE,” discloses the coating of diamond-like carbon film on the roller die surface to form the microstructures, with the thickness of the diamond-like carbon film of about 200 nm. This diamond-like carbon film is coated using a plasma-enhanced chemical vapor deposition (PECVD) method. The apparatus of this US invention comprises a reaction chamber, a plate-shaped nozzle configured to eject reaction gas and inert gas into the reaction chamber, and an electrode electrically connected to an alternating current power source. In the coating process, the roller die rotates around a central axis.

[0008] CN 111593321 A, titled “METHOD FOR DEPOSITING DLC (DIAMOND LIKE CARBON) COATING THROUGH TWIN-LOAD MEDIUM-FREQUENCY ALTERNATING-CURRENT PECVD (PLASMA ENHANCED CHEMICAL VAPOR DEPOSITION),” discloses a diamond-like carbon film coating (using the twin-loaded mediumfrequency AC PECVD method). Two groups of workpieces are arranged into a circle or in parallel equidistantly in a vacuum chamber. The workpieces are rotated and electrically connected using an intermediate frequency AC power source as a plasma excitation source. The workpieces are then coated with diamond-like carbon film.

[0009] CN 111926301 A, titled “DLC COATING PROCESS,” discloses a diamond-like carbon film coating process which can be performed at a low temperature using PVD and PECVD methods. A magnetic-control sputtering target and a discharge electrode, which are used in the installation of a magnetic field coil, help to increase the ionization rate of carbon-containing gas and the deposition rate of carbon layer.

[0010] CN 212505047 U, titled “PREPARATION EQUIPMENT OF DLC FILM LAYER,” discloses a preparation equipment of diamond-like carbon film layer consists of an equipment main body, an air pump assembly, a magnetron sputtering cathode, and a substrate rotating frame. A plasma enhanced chemical vapor deposition (PECVD) takes place in the equipment main body having an X-shape with an outer surface covered with a conducting layer and conductive plates electrically connected to power supply access ends. The equipment also includes a linear plasma cleaning source and an air exhaust assembly. The frame and the conductive plate material used can be varied.

[0011] JP 2023504812 A, titled “DLC MANUFACTURING EQUIPMENT AND MANUFACTURING METHOD,” discloses a manufacturing equipment and a method for coating a diamond-like carbon film. The manufacturing equipment for coating the diamond-like carbon film comprises a main equipment body having a reaction chamber for placing a workpiece (substrate), a plasma source unit and plasma for supplying reaction gas to the reaction chamber. This gas supply unit is a plasma source unit which is located outside the main equipment body. A radio frequency electric field is applied to the reaction chamber to induce plasma generation. The diamond-like carbon film coating is formed by the reaction gas deposited on the workpiece surface using a plasma enhanced chemical vapor deposition (PECVD) method.

[0012] It can be seen that there has been no mention of a diamond-like carbon film coating equipment or apparatus featuring a simultaneous rotation of a plate or a supporting base of the workpiece to be coated, i.e., a main axis driving the whole placement base of the apparatus and a rotational axis assembled to each workpiece supporting base, around two axes as mentioned in the present invention, which would provide the desired uniform coating thickness and an increase in performance of the product obtained. Moreover, there has been no prior art mentioning the increase in the number of workpieces supporting bases in order to coat more than one workpiece at a time, which increases the production capacity and reduces the operation time.

[0013] SUMMARY OF THE INVENTION

[0014] A diamond-like carbon film coating apparatus comprises a chamber which is installed on a chamber support; a chamber door installed in front of the chamber such that it can be opened and closed repeatedly; a pump installed at the back of the chamber to supply gas for coating the diamond-like carbon film onto a workpiece; and a workpiece support provided inside the chamber at a lower side and connected to a rotation control assembly, which is installed on the chamber support, to support and enable a rotational movement of the workpiece. The coating apparatus is connected to a control system, which stores a set of standard instructions for controlling coating conditions. The workpiece support comprises a central axis, whose upper end has an electrode installed thereon and whose lower end penetrates into a receiving base and is connected to the rotation control assembly to rotate the receiving base to move around the central axis. The said electrode is connected to an end of a rotational axis, wherein the rotational axis has a supporting base for supporting the workpiece and the other end of the rotational axis penetrates into the receiving base and is connected to the rotation control assembly to rotate the supporting base to move around the rotational axis. The diamond-like carbon film coating is performed on the surface of the workpiece using plasma enhanced chemical vapor deposition and radio frequency pulsed electric power. The electrode is further provided with an insulator installed between each electrode to prevent electric current flow.

[0015] The present invention is aimed at developing a diamond-like carbon film coating apparatus with the workpiece supporting base as a whole and each workpiece supporting base capable of rotating around the axes simultaneously to perform the coating biaxially. Also, there is more than one workpiece supporting base in order to coat more than one workpiece at a time and enhance the performance and properties of the workpiece obtained, which would extend the service life, increase the production capacity, and reduce the operation time.

[0016] BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Fig. 1 shows an embodiment of the diamond-like carbon film coating apparatus according to the present invention. Fig. 2 shows an embodiment of the workpiece support of the diamond-like carbon film coating apparatus according to the present invention.

[0018] DETAILED DESCRIPTION

[0019] Various embodiments of the present invention related to the diamond-like carbon film coating apparatus will now be described.

[0020] Any aspects shown herein shall also encompass the application to other aspects of the present invention, unless stated otherwise.

[0021] Technical or scientific terms used herein have the meanings as understood by a person skilled in the art, unless stated otherwise.

[0022] Any tools, devices, methods, or chemicals mentioned herein shall refer to tools, devices, methods, or chemicals commonly practiced or used by those skilled in the art, unless expressly stated to be particular or specific tools, devices, methods, or chemicals for the present invention.

[0023] The details of the invention will be set forth hereinafter without the intention of limiting the scope of the invention in any way.

[0024] The present invention relates to the diamond-like carbon film coating apparatus. According to Fig. 1, the diamond-like carbon film coating apparatus comprises a chamber 3 which is a closed area, preferably a square-shaped area, installed on a chamber support 1, which comprises four columns located at each corner of a chamber support plate to connect an upper chamber support plate to a lower chamber support plate. The front side of the chamber 3 is provided with a chamber door 2 with at least one connector 21 connecting the chamber 3 to the chamber door 2 such that the chamber door 2 can be opened and closed repeatedly. Preferably, the chamber door 2 is connected to the chamber 3 such that it can be opened to no less than 180 degrees. The back side of the chamber 3 is provided with a pump 4 to supply gas for coating the diamond-like carbon film.

[0025] In an embodiment, the pump 4 is a high-vacuum pump.

[0026] Inside the chamber 3 on a lower side is provided with a workpiece support 5, which preferably has a circular shape. The lower side of the workpiece support 5 is connected to a rotation control assembly 60, which is installed on the upper chamber support plate of the chamber support 1 to support and enable a rotational movement in order to coat the diamondlike carbon film on the surface of the workpiece 100. The workpiece 100 which is suitable for coating is a metal workpiece. The coating apparatus is connected to a control system, which stores a set of standard instructions for controlling coating conditions, e.g., gas flow rate, coating temperature, coating pressure, and rotational speed. The control system also records the conditions of each coating.

[0027] In a lower position below the installation of the workpiece support 5 is provided with at least one slide rail 50, which is connected to the lower side of a receiving base 51 for moving the receiving base 51, which is a part of the slide rail 50, into or out of the chamber 3.

[0028] According to Fig. 2, the workpiece support 5 comprises a central axis 52, which is a metal axis having at least one electrode 55 installed at an upper end such that the electrode extends from a center of the central axis 52 and a lower end penetrates into the receiving base 51 and is connected to the rotation control assembly 60 to rotate the receiving base 51, which is a plate with a flat surface, to move around the central axis 52.

[0029] The said electrode 55 is connected to an end of a rotational axis 54, which is a metal axis. The rotational axis 54 has at least one supporting base 53, which is a plate with a flat surface, preferably circular in shape, installed thereon to support the workpiece 100. The supporting base

[0030] 53 is fitted to the rotational axis 54 using an attachment means, such as a nut or a screw, such that they can be detached from each other and fitted together. The other end of the rotational axis

[0031] 54 penetrates into the receiving base 51 and is connected to the rotation control assembly 60 to rotate the supporting base 53 to move around the rotational axis 54. The radio frequency pulsed electric power is supplied from a power supply to the electrode 55. The power is transferred along the rotational axis 54 to the supporting base 53 having the workpiece 100 placed thereon to form plasma enhanced chemical vapor deposition for coating the diamond-like carbon film on the surface of the workpiece 100.

[0032] The electrode 55 is provided with an insulator 56 installed between each electrode 55 to prevent electric current flow.

[0033] In another embodiment, the receiving base 51 and the rotational axis 54 enable a rotational movement, which is selected from any one of a rotation of the receiving base 51 around the central axis 52 or a rotation of the supporting base 53 around the rotational axis 54 or a simultaneous rotation of the receiving base 51 around the central axis 52 and the supporting base 53 around the rotational axis 54. The simultaneous rotation of the receiving base 51 around the central axis 52 and the supporting base 53 around the rotational axis 54 is preferred.

[0034] In another embodiment, the central axis 52 and the rotational axis 54 are preferably made of copper due to their high electrical conductivity. In another embodiment, the supporting base 53 can be installed on the rotational axis 54 in more than one position such that the supporting base 53 is fitted to the rotational axis 54 using an attachment means, such as a nut or a screw, or the supporting base 53 is assembled to any part of the rotational axis 54 using the attachment means, such as a nut or a screw.

[0035] In another embodiment, the rotational axis 54, on the side connected to the rotation control assembly 60, is provided with an insulator installed on any part of the rotational axis 54 in at least one position to prevent electric current flow.

[0036] In another embodiment, the electrode 55 is preferably made of copper.

[0037] In another embodiment, the receiving base 51 is provided with at least one handle 57 to be held to move the receiving base 51 into or out of the chamber 3.

[0038] In another embodiment, the insulator 56 is preferably made of polytetrafluoroethylene.

[0039] As an example, the diamond-like carbon film coating apparatus can be operated by placing the workpiece 100 which is required to be coated on the supporting base 53 inside the chamber 3, wherein said supporting base 53 can be installed in more than one position such that it is connected to the rotation control assembly 60. The supporting base 53 is placed on the workpiece support 5, which is also connected to the rotation control assembly 60. The coating step begins with providing the radio frequency pulsed electric power through the electrode 55, which is connected to the upper end of the rotational axis 54, to enable the diamond-like carbon film coating using the plasma enhanced chemical vapor deposition method. During the operation, the apparatus is supplied with gas through the pump 4, which is connected to the chamber 3. A simultaneous rotation of the receiving base 51 around the central axis 52 and the supporting base 53 around the rotational axis 54 is performed. The operation of the apparatus is controlled by the control system, which stores a set of standard instructions to control the coating conditions.

[0040] Any modifications or changes may be clearly understood and can be made by a person skilled in the art under the scope and spirit of the present invention as shown in the appended claims.

[0041] BEST MODE OF THE INVENTION

[0042] Best mode of the invention is as described in the detailed description of the invention.

Claims

WHAT IS CLAIMED IS:

1. A diamond-like carbon film coating apparatus comprises a chamber (3) which is a closed area installed on a chamber support (1); a chamber door (2) installed in front of the chamber (3) with at least one connector (21) connecting the chamber (3) to the chamber door (2) such that the chamber door can be opened and closed repeatedly; a pump (4) installed at the back of the chamber (3) to supply gas for coating the diamond-like carbon film onto a workpiece (100); and a workpiece support (5) provided inside the chamber (3) at a lower side and connected to a rotation control assembly (60), which is installed on the chamber support (1), to support and enable a rotational movement of the workpiece (100) to coat the diamond-like carbon film onto a surface of the workpiece (100), wherein the coating apparatus is connected to a control system, which stores a set of standard instructions for controlling coating conditions characterized in that the workpiece support (5) comprises a central axis (52) which is a metal axis having at least one electrode (55) installed at an upper end such that the electrode extends from a center of the central axis (52) and a lower end penetrates into a receiving base (51) and is connected to the rotation control assembly (60) to rotate the receiving base (51), which is a plate with a flat surface, to move around the central axis (52), the said electrode (55) is connected to an end of a rotational axis (54), which is a metal axis having at least one supporting base (53) , which is a plate with a flat surface installed thereon to support the workpiece ( 100), and the other end of the rotational axis ( 54) penetrates into the receiving base ( 51) and is connected to the rotation control assembly (60) to rotate the supporting base (53) to move around the rotational axis (54), wherein radio frequency pulsed electric power is supplied from a power supply to the electrode (55) to form plasma enhanced chemical vapor deposition for coating the diamond-like carbon film on the surface of the workpiece (100) and the electrode (55) is provided with an insulator (56) installed between each electrode (55) to prevent electric current flow.

2. The diamond-like carbon film coating apparatus according to claim 1, wherein the receiving base (51) and the rotational axis (54) enable a rotational movement, which is selected from any one of a rotation of the receiving base (51) around the central axis (52) or a rotation of the supporting base (53) around the rotational axis (54) or a simultaneous rotation of the receiving base (51) around the central axis (52) and the supporting base (53) around the rotational axis (54).

3. The diamond-like carbon film coating apparatus according to claim 1, wherein the central axis (52) and the rotational axis (54) are preferably made of copper.

4. The diamond-like carbon film coating apparatus according to claim 1, wherein the supporting base (53) can be installed on the rotational axis (54) in more than one position such that the supporting base (53) is fitted to the rotational axis (54) using an attachment means, or the supporting base (53) is assembled to any part of the rotational axis (54) using the attachment means.

5. The diamond-like carbon film coating apparatus according to claim 1, wherein the rotational axis (54), on the side connected to the rotation control assembly (60), is provided with an insulator installed on any part of the rotational axis (54) in at least one position to prevent electric current flow.

6. The diamond-like carbon film coating apparatus according to claim 1, wherein the electrode (55) is preferably made of copper.

7. The diamond-like carbon film coating apparatus according to claim 1, wherein the receiving base (51) is provided with at least one handle (57) to be held to move the receiving base (51) into or out of the chamber (3).

8. The diamond-like carbon film coating apparatus according to claim 1, wherein the chamber (3) has at least one slide rail (50) installed in a lower position below the installation of the workpiece support (5) such that it is connected to a lower side of the receiving base (51) for moving the receiving base (51) into or out of the chamber (3).. The diamond-like carbon film coating apparatus according to claim 1, wherein the insulator (56) is preferably made of polytetrafluoroethylene.

10. The diamond-like carbon film coating apparatus according to claim 1, wherein the pump (4) is a high-vacuum pump.

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