A device for increasing deposition rate of magnetic filtered arc ion plating

Abstract

The application relates to a device for improving the deposition rate of a magnetic filtering arc ion plating, which comprises a filter, the filter is composed of multiple head-to-tail connected pipe sections, the pipe sections are straight pipe sections, and the number of the pipe sections is greater than or equal to 3. The above scheme provided by the application can effectively filter out micro-particles in plasma by changing the structure of the filter, is suitable for filtering and purifying plasma of various metal, alloy and graphite cathode target materials, and the resistance of the plasma in the magnetic filter is reduced when the plasma travels in the magnetic filter, so that the deposition rate is improved.

Description

Technical Field

[0001] This invention relates to the field of magnetic filtering arc ion plating technology, and more specifically to a device for improving the deposition rate of magnetic filtering arc ion plating. Background Technology

[0002] As is well known, arc ion plating technology produces films with excellent properties such as high density and good adhesion due to its extremely high ionization rate. However, during the plating process, the droplets formed by arc excitation are the root cause of surface roughness in the film, which to some extent limits its application range and performance.

[0003] Magnetic filtration arc ion plating technology typically involves winding a metal coil around the outer edge of an angled bend and passing an electric current through it, creating a ring-shaped magnetic field inside and outside the bend. When the arc is activated, a plasma beam is generated near the target surface. This beam contains uncharged droplets and charged ions. Charged ions with smaller radii of rotation are constrained by the magnetic field and can pass smoothly through the bend, reaching the product surface to form a film. Uncharged droplets or charged ions with larger radii of rotation directly collide with the inner wall of the bend, thus filtering out large particles. However, while traditional magnetic filtration arc ion plating technology reduces surface roughness, it significantly reduces the deposition rate, resulting in a substantial decrease in production efficiency. In actual production, there is a high demand for ultra-hard Ta-C films exceeding 10 μm in thickness. Traditional magnetic filtration arc ion plating technology is no longer efficient enough and presents numerous technical challenges. Summary of the Invention

[0004] The purpose of this invention is to provide an apparatus for improving the deposition rate of magnetically filtered arc ion plating, which can be used to solve the above-mentioned technical problems.

[0005] The specific technical solution adopted by this invention is as follows:

[0006] An apparatus for improving the deposition rate of magnetically filtered arc ion plating, characterized in that: it includes a filter, which is composed of pipe segments connected end to end, wherein the pipe segments are straight pipe segments and the number of pipe segments is ≥3.

[0007] A further proposed solution is to use an arc-shaped transition connection at the junction of adjacent pipe sections.

[0008] The internal magnetic field strength of the pipe section located in the middle of the filter is greater than that of the pipe sections at both ends of the filter.

[0009] An annular baffle is installed in the middle section of the filter.

[0010] By changing the number of coil turns on the outside of each pipe section, the internal magnetic field strength of the middle pipe section is made greater than that of the pipe sections at both ends.

[0011] The coils installed on the outside of each pipe section are formed by winding the same electromagnetic wire.

[0012] The pipeline section includes sections A, B, and C. Section B is located between sections A and C. The centerlines of sections A, B, and C are in the same plane. The inlet of section A and the outlet of section C are arranged at a 90° angle.

[0013] The excitation current of the electromagnetic wire is 8 to 20 A.

[0014] The coils of pipe sections A and C have N turns each, and the coil of pipe section B has M turns, with MN=6.

[0015] The inner diameter of pipe section B is R1, and the inner diameter of the annular baffle is R2. R1:R2 = (100-300) mm:(30-150) mm.

[0016] The above-mentioned solution provided by the present invention can effectively filter out microscopic particles in plasma by changing the structure of the filter. It is suitable for filtering and purifying plasmas of various cathode targets such as metals, alloys, and graphite. At the same time, the resistance of plasma is reduced when it travels in the magnetic filter, thereby improving the deposition rate. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a traditional filter.

[0018] Figure 2 This is a schematic diagram of the structure of the filter of the present invention.

[0019] Figure 3 This is a schematic diagram showing the filter (annular baffle with a small inner diameter) in use.

[0020] Figure 4 This is a schematic diagram showing the filter (annular baffle with a large inner diameter) in use.

[0021] Figure 5 Data analysis graphs showing the relationship between applying different magnitudes of excitation current to conventional filters and the filter of this invention, and the deposition rate.

[0022] The corresponding relationships between the icons and components are as follows.

[0023] 11-A pipe section, 12-B pipe section, 13-C pipe section, 14-annular baffle. Detailed Implementation

[0024] To make the objectives and advantages of this invention clearer, the invention will be specifically described below with reference to embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of the invention and does not strictly limit the scope of protection specifically claimed by the invention. As used herein, the terms "parallel" and "perpendicular" are not limited to their strict geometric definitions, but include tolerances for reasonable and inconsistent machining or human errors.

[0025] like Figure 1 The diagram shows the structure of a traditional filter, which is an arc-shaped structure, as shown below. Figure 2 The diagram shown illustrates one embodiment of the filter of the present invention, namely, a device for improving the deposition rate of magnetically filtered arc ion plating, comprising a filter composed of interconnected pipe segments, wherein the pipe segments are straight pipe segments, and the number of pipe segments is ≥3. Depending on the specific implementation, the number of pipe segments can be selected as 3, 4, or 5. Figure 1 In traditional arc-shaped filters, the distance between the target and the chamber is relatively long, increasing the probability of carbon plasma and droplets colliding with the walls during their journey, resulting in a relatively low deposition rate. This invention, however, designs the filter as a zigzag-shaped bend, which reduces the distance between the target and the chamber. This reduces the obstruction to carbon plasma and droplets as they travel through the filter, thus improving the deposition rate.

[0026] The specific design is as follows: the junction between adjacent pipe sections is an arc-shaped transition connection. The pipe sections include sections A, B, and C, 11, 12, and 13. Section B, 12, is located between sections A, C, 11, and 13. The centerlines of sections A, B, and C, 11, 12, and 13 are in the same plane. The inlet of section A, 11, and the outlet of section C, 13, are arranged at a 90° angle.

[0027] A further proposed solution is to ensure that the internal magnetic field strength of the middle section of the filter is greater than that of the sections at both ends. Furthermore, the number of turns of the coils externally installed on each section is adjusted to make the internal magnetic field strength of the middle section greater than that of the sections at both ends. The coils externally installed on each section are formed by winding the same electromagnetic wire. The number of turns of the coils in sections A and C (11 and 13) is N, and the number of turns of the coil in section B (12) is M, where MN = 6.

[0028] To allow charged plasma to pass smoothly through the filter, a coil with a certain number of turns needs to be wound around the outer edge of the filter. When the coil is energized, it generates a magnetic field that alters the trajectory of the charged plasma, causing it to spiral along the magnetic field lines. This allows it to pass smoothly through the arc-shaped or zigzag-shaped filter and reach the workpiece surface to form a film. For example... Figure 1 , 2As shown, both the arc-shaped and zigzag-shaped bends have a straight section at both the inlet and outlet. This straight section serves to balance the magnetic field, achieving arc stabilization and uniform deposition, and has little impact on the deposition rate. The effect on the deposition rate was tested at the inlet and middle sections of the filter. Experiments revealed that the vast majority of particles are filtered in the middle section. In the middle section, charged particles with higher mass can pass smoothly under the influence of the filtering magnetic field because their radius of rotation is smaller, preventing them from hitting the inner wall of the filter. Charged particles with lower mass have larger radii of rotation, allowing some to pass through. Uncharged atoms or atomic clusters, as well as droplets, are not constrained by the filtering magnetic field, and only a very small number can pass through. Therefore, the present invention divides the bend of the zigzag filter tube into three sections, and winds the coils of the outer rings of the three sections separately. The coil in the middle section has 6 more turns than the coils at both ends. Then, the ends of the three sections of coil are connected to form a whole. During the operation, the magnetic field of the middle section is strengthened, which makes the radius of rotation of charged particles with smaller mass smaller, so that they can pass through the filter smoothly, thereby increasing the deposition rate by more than 20%.

[0029] A more preferred embodiment is that an annular baffle 14 is installed inside the middle section of the filter. With the annular baffle 14 installed inside the filter, large, uncharged particles collide with it, while only charged particles can pass through the through-holes in the middle of the annular baffle 14, thus filtering out large particles and producing a low-roughness and dense coating. For applications requiring high deposition rates, a certain amount of slightly charged particles and a small amount of uncharged particles are needed to enter the deposition chamber. The small pore size of the annular baffle 14 restricts particle entry to some extent. Therefore, increasing the pore size of the annular baffle 14 inside the filter can reduce particle obstruction and contribute to improving the deposition rate. Figure 3 , 4 The distribution of particles under two different annular baffles 14 is shown. It can be seen that after changing the annular baffle 14, the number of particles passing through the annular baffle 14 increases significantly, and some large particles can be filtered out, effectively improving the coating efficiency. Therefore, the preferred solution is that the inner diameter of the B section is R1, and the inner diameter of the annular baffle 14 is R2, specifically R1 = (100-300) mm; R2 = (30-150) mm.

[0030] A further approach is to increase the excitation current of the filter, which can also reduce the radius of rotation of small charged particles, allowing them to pass through the filter more easily, thereby increasing the deposition rate. For example... Figure 5 The variation in deposition rate between conventional filters and the filter of this invention under different excitation currents is shown. Figure 5It is known that with the increase of the applied excitation current, the deposition rate generally shows a trend of first increasing and then decreasing. The deposition rate of the zigzag filter provided by this invention is significantly better than that of the traditional arc-shaped filter. When the magnetic field generated by the excitation current of the filter causes the amount of particles entering the chamber to reach its limit, the magnetic field is already saturated. Further increasing the excitation current will actually affect the stability of arc initiation, thus causing the deposition rate to decrease. Therefore, the excitation current of the electromagnetic wire is set to 8–20 A, preferably 16 A.

[0031] As can be seen from the above, the technical solution provided by the present invention can effectively improve the deposition rate in magnetic filter arc ion plating.

[0032] The above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention. Structures, mechanisms, and operating methods not specifically described or explained in this invention, unless otherwise specified or limited, shall be implemented using conventional methods in the art.

Claims

1. An apparatus for improving the deposition rate of magnetically filtered arc ion plating, characterized in that: Includes a filter, which is composed of pipe segments connected end to end. The pipe segments are straight pipe segments, and the number of pipe segments is ≥3. The junction between adjacent pipe segments is an arc-shaped transition connection. The internal magnetic field strength of the pipe section located in the middle of the filter is greater than that of the pipe sections at both ends of the filter; By changing the number of coil turns on the outside of each pipe section, the internal magnetic field strength of the middle pipe section is made greater than that of the pipe sections at both ends. The pipe sections include sections A, B, and C, with section B located between sections A and C. The centerlines of sections A, B, and C are in the same plane, and the inlet of section A and the outlet of section C are arranged at a 90° angle. The excitation current of the electromagnetic wire is 8 to 20 A. The number of coil turns in sections A and C is N, and the number of coil turns in section B is M, with MN = 6.

2. The apparatus for improving the deposition rate of magnetically filtered arc ion plating according to claim 1, characterized in that: An annular baffle is installed in the middle section of the filter.

3. The apparatus for improving the deposition rate of magnetically filtered arc ion plating according to claim 1, characterized in that: The coils installed on the outside of each pipe section are formed by winding the same electromagnetic wire.

4. The apparatus for improving the deposition rate of magnetically filtered arc ion plating according to claim 1, characterized in that: The inner diameter of pipe section B is R1, and the inner diameter of the annular baffle is R2. R1:R2 = (100-300) mm:(30-150) mm.

Images