Method for vacuum coating by means of continuous magnetron sputtering and use thereof

Abstract

This invention provides a method for vacuum coating using continuous magnetron sputtering and its application. The method includes steps such as substrate dust removal, cleaning and activation, depositing an adhesion-enhancing layer, depositing a copper film layer, and reverse coating. This invention also discloses its application in coating on automotive power electronic components that carry and connect to them. By controlling the coating power, working gas pressure, and argon flow rate, the resulting film exhibits good uniformity, low resistance, and strong conductivity, achieving the same conductivity while maintaining a film thickness that is only 1 / 2 to 2 / 3 that of electroplating.

Description

Technical Field

[0001] This invention belongs to the field of coating technology, specifically relating to a method for vacuum coating using continuous magnetron sputtering and its application. Background Technology

[0002] Vacuum coating refers to a method of heating a metallic or non-metallic material under high vacuum conditions, causing it to evaporate and condense onto the surface of the workpiece (metal, semiconductor, or insulator) to form a thin film. Chinese Patent Publication No. CN115161590A discloses a magnetron sputtering method for vacuum coating, which includes the following steps: 1) Heating a magnesium-aluminum alloy for homogenization treatment, followed by annealing at a certain temperature to obtain a pretreated sample; 2) Performing low-temperature plasma treatment on the pretreated sample from step 1): The pretreated sample from step 1) is cut, and low-temperature plasma surface modification treatment is performed at room temperature and in an oxygen atmosphere using a low-temperature plasma treatment device; 3) After the treatment in step 2), magnetron sputtering coating is performed immediately to deposit a TiN thin film on the sample surface: using JGP... The coating was performed using a Type 560 magnetron sputtering system with a titanium target. Argon was used as the protective gas, and nitrogen as the reactive gas. The working pressure for the coating process was 0.5 ppm. 1.0 Pa, titanium target sputtering power is 100 200W; Argon flow rate 30 40 mL / min, nitrogen flow rate 1 2 mL / min, sputtering temperature 400 500℃. The substrate is a magnesium-aluminum alloy, and the film obtained by selecting conditions such as titanium target sputtering power, sputtering temperature, coating working gas pressure, and airflow has high surface hardness and wear resistance.

[0003] Magnetron sputtering, as a core technology for preparing high-quality conductive thin films, has become an indispensable key process in fields such as flat panel displays, solar cells, and touch panels. Therefore, it is necessary to develop a metal film with thinness, good uniformity, low resistance, and strong conductivity that can be deposited on ceramics using continuous magnetron sputtering for vacuum deposition. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for vacuum coating using continuous magnetron sputtering and its application, which produces a film with good uniformity, low resistance, and strong conductivity, achieving the same conductivity while the film thickness is only 1 / 2 to 2 / 3 of that of electroplating.

[0005] The present invention includes a method for vacuum coating using continuous magnetron sputtering, comprising the following steps:

[0006] (1) Place the substrate on a tray, lay it horizontally, and remove dust.

[0007] (2) Under vacuum conditions, 900-1100 Sccm of argon gas is introduced, the current is 0.8-1.2A, the voltage is 3600-3900V, and the pressure is controlled at 1-10Pa to clean and activate the surface of the substrate.

[0008] (3) Under high vacuum conditions, 800-1000 Sccm of argon gas is introduced, the pressure is adjusted to 0.1-0.5Pa, the sputtering power is 28-32Kw, and a high adhesion target is used to coat the substrate surface to form an adhesion enhancement layer.

[0009] (4) Under high vacuum conditions, 900-1100 argon gas is introduced, the pressure is controlled at 0.1-0.5 Pa, the sputtering power is 33-37 Kw, and a copper film layer is deposited;

[0010] (5) Flip it over and repeat steps (2)-(4) to complete the coating on the other side.

[0011] In one embodiment, the high-adhesion target material in step (3) is one of NiCr and Ti.

[0012] In one embodiment, the substrate is a ceramic sheet.

[0013] In one embodiment, the adhesion enhancement layer has a thickness of 5-10 nm; the copper film layer has a thickness of 2-4 μm.

[0014] In one embodiment, the coating speed in step (3) is 3-10 m / min.

[0015] In one embodiment, the cleaning and activation method in step (2) is either high-pressure plasma method or ion source method.

[0016] In one embodiment, 1000 Sccm of argon gas is introduced in step (2), with a current of 1.0A and a voltage of 3730V.

[0017] In one embodiment, 900 Sccm of argon gas is introduced in step (3), and the sputtering power is 30 kW.

[0018] In one embodiment, 1000 Sccm of argon gas is introduced in step (4), and the sputtering power is 35 kW.

[0019] Another object of the present invention is to provide an application of the above-described method of vacuum coating using continuous magnetron sputtering in coating automotive power electronic components that carry and connect to the vehicle.

[0020] The beneficial effects of this invention are:

[0021] (1) By using the sputtering method of the present invention, the sputtered film obtained by reasonably controlling process parameters such as sputtering power, working gas pressure, and argon flow rate is continuous and uniform, the film thickness can be precisely controlled, the copper film on the surface has strong conductivity, and the electrical stability is high when used in automobiles to carry and connect power electronic components.

[0022] (2) The sputtering method of the present invention ensures that the film thickness uniformity and repeatability are both ≤±2%, thus ensuring the stability of the resistance value; the raw materials are more economical. By preparing a copper film with higher density than electroplating, the copper film has stronger conductivity. The film thickness is only 1 / 2-2 / 3 of that of electroplating to achieve the same conductivity; the equipment is a horizontal structure, and the product can be placed directly on the tray without the need for shielding fixtures, and the fixture cost is 0 yuan; the sputtering method of the present invention does not require the use of fixtures, is simple and easy to operate, and there is no need to worry about environmental protection issues;

[0023] (3) The present invention uses a material with good adhesion to both ceramic sheet and Cu. The high-adhesion target material is plated on the ceramic surface as a transition, thereby ensuring good adhesion of the copper plating layer. Attached Figure Description

[0024] Figure 1 Image of the Al2O3 ceramic substrate before coating;

[0025] Figure 2 This is an image showing the effect of the Al2O3 ceramic plate after coating.

[0026] Figure 3 The Rx test value is after coating.

[0027] Figure 4 The value of sheet resistance R after coating is measured. Detailed Implementation

[0028] Example 1

[0029] A method for vacuum coating using continuous magnetron sputtering:

[0030] Step 1: Coating equipment: GSV1006-4 continuous coating line, Al2O3 ceramic substrate, 0.63×110×110mm, 80pcs. Place the substrate on a tray, 20mm high, horizontally, and perform dust removal treatment on the product.

[0031] Step 2: Under vacuum conditions, 1000 Sccm of argon gas is introduced, with a current of 1.0A and a voltage of 3713V, 10 times, and the pressure is controlled at 1-10Pa to clean and activate the substrate surface.

[0032] Step 3: Under high vacuum conditions, 900 Sccm of argon gas is introduced, the pressure is adjusted to 0.1-0.5 Pa, the sputtering power is 30 kW, the voltage is 476 V, the current is 63.3 A, and this is repeated 5 times. Argon gas is introduced again to adjust the pressure to 0.1-0.5 Pa. The Ti target is placed at target position #2, and the Ti target is used to coat the ceramic surface as a transition.

[0033] Step 4: Under high vacuum conditions, 1000 Sccm of argon gas is introduced, the pressure is controlled at 0.1-0.5 Pa, the sputtering power is 35 kW, the voltage is 743 V, the current is 45.9 A, and the sputtering is repeated 30 times. The Cu target is placed at position 4#, and the film thickness is precisely controlled to 3 μm.

[0034] Table 1. First-side beat statistics for 3μm copper plating on Al2O3 substrates.

[0035]

[0036] Step 5: Flip it over.

[0037] Step 6: Under vacuum conditions, 1000 Sccm of argon gas is introduced, with a current of 1.0A and a voltage of 3689V, 10 times, and the pressure is controlled at 1-10Pa to clean and activate the substrate surface.

[0038] Step 7: Under high vacuum conditions, introduce 900 Sccm of argon gas, adjust the pressure to 0.1-0.5 Pa, sputtering power 30 kW, voltage 471 V, current 63.3 A, 5 times, introduce argon gas to adjust the pressure to 0.1-0.5 Pa, place the Ti target at target position 2, and use the Ti target to deposit on the ceramic surface as a transition.

[0039] Step 8: Under high vacuum conditions, 1000 Sccm of argon gas is introduced, the pressure is controlled at 0.1-0.5 Pa, the sputtering power is 35 kW, the voltage is 796 V, the current is 44.1 A, and the sputtering is repeated 30 times. The Cu target is placed at position 4#, and the film thickness is precisely controlled to 3 μm.

[0040] Table 2. First-side beat statistics for 3μm copper plating on Al2O3 substrates.

[0041]

[0042] Example 2

[0043] A method for vacuum coating using continuous magnetron sputtering:

[0044] Step 1: Coating equipment: GSV1006-4 continuous coating line, Al2O3 ceramic substrate, 0.63×110×110mm, 80pcs. Place the substrate on a tray, 20mm high, horizontally, and perform dust removal treatment on the product.

[0045] Step 2: Under vacuum conditions, 1000 Sccm of argon gas is introduced, with a current of 1.0A and a voltage of 3730V, 10 times, and the pressure is controlled at 1-10Pa to clean and activate the substrate surface.

[0046] Step 3: Under high vacuum conditions, introduce 900 Sccm of argon gas, adjust the pressure to 0.1-0.5 Pa, sputtering power 30 kW, voltage 470 V, current 63.8 A, 5 times, introduce argon gas to adjust the pressure to 0.1-0.5 Pa, place the Ti target at target position 2, and use the Ti target to deposit on the ceramic surface as a transition.

[0047] Step 4: Under high vacuum conditions, 1000 Sccm of argon gas is introduced, the pressure is controlled at 0.1-0.5 Pa, the sputtering power is 35 kW, the voltage is 783 V, the current is 44.2 A, and the sputtering is repeated 30 times. The Cu target is placed at position 4#, and the film thickness is precisely controlled to 3 μm.

[0048] Table 3. First-side beat statistics for 3μm copper plating on Al2O3 substrates.

[0049]

[0050] Step 5: Flip it over.

[0051] Step 6: Under vacuum conditions, 1000 Sccm of argon gas is introduced, with a current of 1.0A and a voltage of 3827V, 10 times, and the pressure is controlled at 1-10Pa to clean and activate the substrate surface.

[0052] Step 7: Under high vacuum conditions, introduce 900 Sccm of argon gas, adjust the pressure to 0.1-0.5 Pa, sputtering power 30 kW, voltage 475 V, current 63.4 A, 5 times, introduce argon gas to adjust the pressure to 0.1-0.5 Pa, place the Ti target at target position #2, and use the Ti target to deposit on the ceramic surface as a transition.

[0053] Step 8: Under high vacuum conditions, 1000 Sccm of argon gas is introduced, the pressure is controlled at 0.1-0.5 Pa, the sputtering power is 35 kW, the voltage is 763 V, the current is 46.4 A, and the sputtering is repeated 30 times. The Cu target is placed at position 4#, and the film thickness is precisely controlled to 3 μm.

[0054] Table 4. First-side beat statistics for 3μm copper plating on Al2O3 substrates.

[0055]

[0056] Comparative Example 1

[0057] The sputtering power in steps three and seven of Example 1 was adjusted to 40 kW, and the sputtering power in steps four and eight was adjusted to 45 kW. The rest was the same as in Example 1.

[0058] Comparative Example 2

[0059] Replace the Ti target in step 3 of Example 1 with a TiN target, and everything else is the same as in Example 1.

[0060] Comparative Example 3

[0061] In steps three, four, seven, and eight of Example 1, the pressure of argon gas was adjusted to 5.0 Pa, and the rest was the same as in Example 1.

[0062] Comparative Example 4

[0063] In Example 1, the sputtering power in steps 3 and 7 was adjusted to 40 kW, and argon gas was introduced to adjust the pressure to 5.0 Pa. In steps 4 and 8, the sputtering power was adjusted to 45 kW, and argon gas was introduced to adjust the pressure to 5.0 Pa. The rest was the same as in Example 1.

[0064] After coating Examples 1-2 and Comparative Examples 1-4, performance tests were conducted, and the results are shown in the table below.

[0065] Table 5 Results of various performance tests

[0066]

[0067] Examples 1-2 use the continuous magnetron sputtering vacuum coating method of this application to obtain uniform and fine film layers with OK adhesion test results, low resistance, and excellent conductivity.

[0068] Comparative Example 1 increased the deposition power. At higher power, the stress of the deposited film increased, and high power would disrupt the magnetic field distribution, reduce the plasma density, and lead to unstable sputtering rate and increased grain size.

[0069] In Comparative Example 2, replacing the Ti target with a TiN target resulted in a significant decrease in coating adhesion, making the coating prone to peeling off.

[0070] In Comparative Example 3, the gas pressure was increased, thereby increasing the deposition rate. However, an excessively fast deposition rate can easily lead to a loose film and poor adhesion.

[0071] Comparative Example 4 increased the deposition power and gas pressure, which led to a decrease in coating uniformity, adhesion, and conductivity.

[0072] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of protection of this application is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of one or more embodiments of this application as described above, which are not provided in detail for the sake of brevity.

[0073] One or more embodiments in this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments in this application should be included within the protection scope of this application.

Claims

1. A method for vacuum coating by means of continuous magnetron sputtering, characterized in that Includes the following steps: (1) Place the substrate on a tray, lay it horizontally, and remove dust. (2) Under vacuum conditions, 900-1100 Sccm of argon gas is introduced, the current is 0.8-1.2A, the voltage is 3600-3900V, and the pressure is controlled at 1-10Pa to clean and activate the surface of the substrate. (3) Under high vacuum conditions, 800-1000 Sccm of argon gas is introduced, the pressure is adjusted to 0.1-0.5Pa, the sputtering power is 28-32Kw, and a high adhesion target is used to coat the substrate surface to form an adhesion enhancement layer. (4) Under high vacuum conditions, 900-1100 argon gas is introduced, the pressure is controlled at 0.1-0.5 Pa, the sputtering power is 33-37 Kw, and a copper film layer is deposited; (5) Flip it over and repeat steps (2)-(4) to complete the coating on the other side; The high-adhesion target material in step (3) is one of NiCr and Ti; The adhesion enhancement layer has a thickness of 5-10 nm; the copper film layer has a thickness of 2-4 μm.

2. The method for vacuum coating by continuous magnetron sputtering according to claim 1, characterized in that The substrate is a ceramic sheet.

3. The method for vacuum coating by continuous magnetron sputtering according to claim 1, wherein the magnetron is arranged in the vicinity of the substrate. The coating speed in step (3) is 3-10 m / min.

4. The method for vacuum coating by continuous magnetron sputtering according to claim 1, wherein The cleaning and activation method in step (2) is either high-pressure plasma method or ion source method.

5. The method for vacuum coating by continuous magnetron sputtering according to claim 1, wherein the magnetron is arranged in the vicinity of the substrate. In step (2), 1000 Sccm of argon gas is introduced, with a current of 1.0A and a voltage of 3730V.

6. The method for vacuum coating using continuous magnetron sputtering as described in claim 1, characterized in that, In step (3), 900 Sccm of argon gas is introduced and the sputtering power is 30Kw.

7. The method for vacuum coating using continuous magnetron sputtering as described in any one of claims 1-6, characterized in that, In step (4), 1000 Sccm of argon gas is introduced and the sputtering power is 35Kw.

8. An application of a method for vacuum coating using continuous magnetron sputtering as described in any one of claims 1-7 in coating automotive load-bearing and connecting power electronic components.

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