Vacuum ion sputtering coating machine and method for continuous metallization of ultra-thin films

Abstract

The present application relates to a kind of vacuum ion sputtering coater and ultra-thin film continuous metallization method.The vacuum ion sputtering coater includes vacuum cover, target material, column cover, lifting column, rotating base, electric cross bar, refrigeration device, sample clamp, side column, base, hollow column and the like, through the rotation of lifting column in horizontal plane and the synchronous rotation of rotating base and sample clamp thereon, uniform coating is realized;Through the up-and-down movement of lifting column in vertical direction and the rotation of electric cross bar, the sample clamp is turned over;Through the heat dissipation and cooling effect of refrigeration device, ensure that ultra-thin film is always metallized at low temperature, avoid the phenomenon such as concave, thermal breakdown and coating uneven.The whole device has a series of advantages such as simple structure, easy to use and maintain, good metal film quality, high degree of automation, and has good application prospect in the field of vacuum ion sputtering coating.

Description

Technical Field

[0001] The present invention relates to the technical field of ion sputtering vacuum coating, and in particular to a vacuum ion sputtering coating machine and an ultra-thin film continuous metallization method. Background Art

[0002] When metallizing the front and back sides of a film in the laboratory, the base of a common commercial ion sputtering coating machine cannot rotate and continuously metallize. There is no rotating device on the base designed to receive sputtered atoms in all directions, which makes the thickness uniformity of the metallized film poor. When the other surface of the film needs to be metallized, the vacuum cover needs to be opened and the sample needs to be manually flipped. This operation directly causes a large change in the vacuum degree, gas, and plasma in the container, which affects the quality of the film and makes it difficult to keep consistent with the metallized film in the previous step. In addition, if the ultra-thin film is not temperature-controlled, the heat brought by the excited atoms will converge on the ultra-thin film, and the film will sag, deform, or even thermally break down, resulting in uneven thickness of the metallized film and unstable dielectric properties. Due to the influence of thermal radiation and high-kinetic energy atoms caused by ion sputtering, the molecular chains on the surface of polymer ultra-thin films with a thickness of less than 5μm are interrupted, resulting in uneven sag or deformation, leading to abnormal dielectric loss.

[0003] Currently, thin films produced in laboratories and industry tend to be thinner and lighter. For example, when preparing high-capacity, small-volume capacitors, the thickness of industrial biaxially oriented polypropylene films is required to be less than 10μm. The thinnest industrially produced films are generally over 4μm thick. If thinner films are produced, they are prone to film breakage. The thinner the film, the greater the impact of ion sputtering. Based on the principle of ion sputtering coating, the coating process inevitably encounters the problem of uneven deposition of atoms in all directions, and the method of atomic deposition on a single side of the film also limits the efficiency of the coating. During the sputtering process, the excited atoms may become too hot, causing deformation of the film or even thermal breakdown.

[0004] In order to solve the problem of thickness uniformity of metallized films, Chinese patent CN 214361658 U discloses a substrate rotating frame mechanism for sensor ion beam sputtering coating equipment. This solution uses a rotating motor to drive a rotating shaft to rotate around a vacuum box, thereby achieving uniform coating. In order to solve the problem of high heat caused by sputtered atoms during the coating process, Chinese patent CN 1113881925A discloses a workpiece fixed cooling device for vacuum ion plating. This solution uses a water pump to pump external coolant into a cooling pipe, and the workpiece is cooled by the cooperation of the cooling pipe and fins, thereby improving the quality of the workpiece. However, the above-mentioned rotating device and traditional water cooling device designed at present are both designed separately and cannot solve the problems of thickness uniformity and dielectric property stability of metallized films at the same time. In addition, there are a series of problems such as large equipment size, complicated operation, and low efficiency.

[0005] For these reasons, current ion sputtering vacuum coating equipment and processes suffer from uneven thickness of metallized films, unstable dielectric properties, and inability to continuously metallize. Therefore, there is an urgent need to develop a vacuum ion sputtering coating machine for continuous metallization of ultra-thin films that meets the requirements for achieving uniform thickness, stable dielectric properties testing, and continuous operation. Summary of the Invention

[0006] The purpose of the present invention is to solve the problems commonly existing in the existing ion sputtering coating technology, such as uneven thickness of the metallized film, surface defects, unstable dielectric loss and discontinuous metallization, and to provide a new vacuum ion sputtering coating machine.

[0007] To achieve the above object, the technical solution adopted by the present invention is:

[0008] The vacuum ion sputtering coating machine mainly comprises a sealed housing and a lifting column (4), a rotating base (5), a flipping device (6), a refrigeration device (7), and a sample fixture (8) located inside the sealed housing; the rotating base (5) is fixedly connected to the lifting column (4) and rotates in a horizontal plane and reciprocates in a vertical linear motion along with the lifting column (4); the refrigeration device (7) is located at the bottom of the rotating base (5) and cools the rotating base (5) and the sample fixture (8) thereon; the flipping device is located around the rotating base (5) and is used to flip the sample fixture (8).

[0009] Furthermore, the sealed housing comprises a vacuum cover (1), a column cover (3), and a base (13), and the column cover (3) and the base (13) are sealedly connected to the upper and lower ends of the vacuum cover (1), respectively.

[0010] Furthermore, the column cover (3) is connected to a target material (2), a vacuum tube (10), a power line (11), and an argon gas pipeline (12).

[0011] Further, the vacuum ion sputtering coating machine further comprises a hollow column (14), the top of the hollow column (14) is fixedly connected with the refrigeration device (7), the bottom of the hollow column (14) is fixed on the base (13) of the sealed shell; the lifting column (4) is located inside the hollow column (14), the top of the lifting column (4) is fixedly connected with the base (5) after penetrating through the through hole on the refrigeration device (7), and the bottom of the lifting column (4) is fixed on the base (13) of the sealed shell. The hollow column mainly plays multiple roles of protecting the lifting column, the base and limiting the stroke of the lifting column.

[0012] Further, the refrigeration device (7) is specifically a Peltier effect thermoelectric refrigeration device.

[0013] Further, the turnover device comprises a side column (9) and an electric cross rod (6), the side column (9) is fixed on the side of the rotating base (5), the electric cross rod (6) is fixedly connected with the side column (9) and can be controlled to rotate, and the electric cross rod (6) is detachably movably connected with the sample clamp (8) and drives the sample clamp (8) to turn over.

[0014] Further, the number of the side column (9) and the electric cross rod (6) is both 2, and the side column (9) and the electric cross rod (6) are symmetrically distributed on the two sides of the base (5).

[0015] Further, the electric cross rod (6) is telescopic or foldable.

[0016] Further, a clamping groove (15) is arranged on the sample clamp (8), and the electric cross rod (6) and the sample clamp (8) are clamped together through the clamping groove (15).

[0017] Another object of the present application is to utilize the above-mentioned vacuum ion sputtering coating machine to perform a method for continuously metallizing an ultrathin film, which comprises the following steps: (a) fixing the ultrathin film on the sample clamp (8), placing the sample clamp (8) on the rotating base (5) and covering the column cover (3) to seal; (b) powering on, lowering the lifting column (4) to a predetermined position and keeping rotating, completing uniform coating of one side surface of the ultrathin film, during which the refrigeration device (7) cools the rotating base (5) and the sample clamp (8); (c) raising the lifting column (4) to a predetermined position, extending the electric cross rod (6) of the turnover device into the clamping groove of the sample clamp (8), lowering the lifting column (4) to make the sample clamp (8) leave the rotating base (5), rotating the turnover device to drive the sample clamp (8) to turn over, raising the lifting column (4) to a predetermined position and then retracting the electric cross rod (6), and returning the sample clamp (8) to the rotating base (5); (d) lowering the lifting column (4) to a predetermined position and keeping rotating, completing uniform coating of the other side surface of the ultrathin film, during which the refrigeration device (7) cools the rotating base (5) and the sample clamp (8).

[0018] Furthermore, the ultra-thin film is specifically a polymer film with a thickness of less than 5 μm.

[0019] The present invention has designed and developed a set of controllable lifting and rotating table devices to ensure that the metallized film is evenly deposited on the surface of the film. The added side flipping device allows the upper and lower surfaces of the sample to be continuously metallized under the same conditions, which not only simplifies the process but also ensures the consistency of the metallized film. In addition, the thermoelectric refrigeration device introduced in the present invention can quickly remove the heat brought by sputtering to the sample surface, so that the metallization of the ultra-thin film is carried out at a lower temperature, avoiding problems such as thermal breakdown or surface defects caused by the ultra-thin film being too thin, and ensuring the stability of the performance of the metallized film. The rotating and flipping device works synergistically with the thermoelectric refrigeration device to ultimately produce a metallized film with stable performance, uniform thickness and continuous operation. The entire device has the advantages of simple structure, easy operation, low device modification cost, good effect, etc., and has strong market competitiveness compared with similar equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the vacuum ion sputtering coating machine of the present invention;

[0021] Figure 2 This is a schematic structural diagram of a thermoelectric refrigeration device of a vacuum ion sputtering coating machine of the present invention;

[0022] Figure 3 It is a structural schematic diagram of the lifting and rotating device of the vacuum ion sputtering coating machine of the present invention;

[0023] Figure 4 It is a schematic structural diagram of the turning device of the vacuum ion sputtering coating machine of the present invention.

[0024] Among them, 1-vacuum cover, 2-target material, 3-column cover, 4-lifting column, 5-rotating base, 6-electric crossbar, 7-refrigeration device, 8-sample clamp, 9-side column, 10-vacuum tube, 11-power cord, 12-argon gas pipeline, 13-base, 14-hollow column, 15-card slot, 16-hollow lower round table. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to fully understand the technical solutions and beneficial effects of the present invention, further description will be given below in conjunction with specific embodiments and drawings.

[0026] like Figure 1-4The novel vacuum ion sputtering coating machine mainly includes a vacuum cover 1, a target material 2, a column cover 3, a lifting column 4, a rotating base 5, an electric crossbar 6, a refrigeration device 7, a sample holder 8, a side column 9, a vacuum tube 10, a power cord 11, an argon gas pipeline 12, a base 13, and a hollow column 14, wherein the vacuum cover 1 is fixed on the base 13, and the column cover 3 is fixed on the vacuum cover 1, thereby sealing the remaining components in the vacuum cover 1. A metal target material 2 is fixed on the inner surface of the column cover 3, and is also connected to the vacuum tube 10, the power cord 11, and the argon gas pipeline 12. A lifting column 4 and a hollow column 14 are fixed on the base 13, and the lifting column 4 is coaxially sleeved in the hollow column 14. The top of the hollow column 14 is connected to a hollow lower truncated table 16 and a refrigeration device 7, and the lifting column 4 is fixedly connected to the rotating base 5 after passing through the refrigeration device 7. Side columns 9 are provided on the left and right sides of the rotating base 5 , and an electric crossbar 6 is provided on the top of the side columns 9 . The end of the electric crossbar 6 can be clamped into the sample clamp 8 and driven to rotate to achieve flipping.

[0027] The lifting column 4 can be lifted and lowered vertically after being energized, and the rotating base 5 and the sample holder thereon can also rotate together to achieve uniform coating. The refrigeration device 7 is closely connected to the rotating base 5 and is used to absorb the heat of the thin film sample holder. The height of the vacuum cover 1 is 16 cm, the diameter and height of the hollow column 14 are 3 cm and 8 cm respectively, and the diameter of the refrigeration device 7 at its top is 5 cm; the diameter and height of the lifting column 4 are 1 cm and 12 cm respectively, the diameter of the rotating base 5 at its top is 5 cm, the closest distance between the rotating base 5 and the refrigeration device 7 is 0.5 cm, and the height and diameter of the side column 9 are 12 cm and 1 cm respectively. When the sputtered atoms of the cathode target collide with the remaining gas in the vacuum chamber and scatter in all directions, relative to the originally fixed base, the present invention can make the sample surface evenly receive the excited metal atoms by adjusting the rotation speed of the base.

[0028] First, fix the ultra-thin film with the sample holder 8, then place the sample holder 8 on the rotating base 5, start the lifting column 4 to rotate it and drive the rotating base 5 to rotate, start the vacuum pump to evacuate the inside of the container to 1×10 -3Pa, then start the refrigeration device 7 and introduce argon gas, start the ion source and start coating. The argon gas in the glass cover is used for glow discharge, and the atoms excited from the cathode target are evenly deposited on the sample film. Since the surface of the ultra-thin film is prone to depression, thermal breakdown and uneven coating due to the high energy of sputtering, the thermoelectric refrigeration device can effectively discharge the heat generated by sputtering, ensuring that the sample film is metallized at low temperature. When one side of the ultra-thin film on the sample fixture 8 is metallized, the lifting column 4 is directly controlled to rise to a predetermined height, and the electric cross bar 6 is extended and inserted into the card slot of the sample fixture 8. Then the lifting column 4 is lowered to a predetermined height to prevent the sample fixture 8 from hitting the rotating base 5 when it is flipped over. The card slot 15 and the electric cross bar 6 respectively fix and drive the sample fixture 8 to rotate to complete the flipping. After the flipping is completed, the lifting column 4 rises to the predetermined height so that the sample holder 8 returns to the rotating base 5, and the electric crossbar 6 is retracted. Next, the lifting column 4 descends to the lowest height of the coating (i.e., 0.5 cm away from the refrigeration device 7), and continuous metallization begins on the other side of the film sample.

[0029] like Figure 2 As shown, the cooling device 7 is selected from a thermoelectric cooling device based on the Peltier effect. Its cooling principle can be explained by the change in potential energy when carriers flow through the node: because the potential energy of carriers in metals and semiconductors is different, the carriers will inevitably cause energy transfer when flowing through the node; when the carriers change from lower potential energy to higher potential energy, the node must absorb external energy, and vice versa, it must release energy. The N-type columnar semiconductor material used in the thermoelectric cooling device is Bi2Te3-Bi2Se3, and the P-type columnar semiconductor material is Bi2Te3-Sb2Te3. When direct current passes through the P-type and N-type materials, the node copper sheet will absorb or release heat, and the heat at the node is proportional to the current. The specific formula is:

[0030] Φ=πI=αT c I,

[0031] Where Φ is the heat, α is the thermoelectric potential rate, T c is the cold junction temperature, π is the Peltier coefficient and is related to the properties of the material itself, and I is the current. By adjusting I, the cooling capacity can be controlled.

[0032] Therefore, choosing a semiconductor with a higher thermoelectric potential can improve the cooling effect even at a lower current. The P-type and N-type semiconductors are mechanically connected at the top of the hollow cylinder. The tops of the two semiconductors are connected to a copper hollow lower cone, and the bottom is also connected to a copper sheet. When current flows from the N-type semiconductor to the P-type semiconductor, the copper sheet absorbs heat and cools down, thus conducting away the heat brought by sputtering to the sample surface. Using a cooling device to absorb the heat of the base helps to ensure the smooth rotation of the base and the uniformity of the thickness of the metallized film. Compared with ordinary water cooling and other methods, the use of thermoelectric cooling has the following advantages: ① There are no mechanical rotating parts, so there is no noise, no vibration, easy maintenance, and high reliability; ② The base can be controlled below room temperature and no refrigerant is required; ③ The temperature can be precisely controlled, and the cooling capacity and cooling speed can be flexibly and quickly adjusted by changing the current; ④ Small size and light weight.

Claims

1. A vacuum ion sputtering coating machine, characterized in that: The vacuum ion sputtering coating machine comprises a sealed housing and a lifting column (4), a rotating base (5), a turning device, a refrigeration device (7), and a sample holder (8) located inside the sealed housing; the rotating base (5) is fixedly connected to the lifting column (4) and rotates in a horizontal plane and moves up and down in a vertical direction along with the lifting column (4); the refrigeration device (7) is located on the bottom surface of the rotating base (5) and is used to cool the rotating base (5) and the sample holder (8) thereon; the refrigeration device is specifically a thermoelectric refrigeration device based on the Peltier effect, and the N-type columnar semiconductor material used in the thermoelectric refrigeration device is Bi2T e3-Bi2Se3, the P-type columnar semiconductor material is Bi2Te3-Sb2Te3; an ultra-thin film is fixed on the sample holder (8), and the ultra-thin film is specifically a polymer film with a thickness of less than 5μm; the flipping device is located on both sides of the rotating base (5) and is used to flip the sample holder (8), and the flipping device includes a side column (9) and an electric cross bar (6), the side column (9) is fixed on the side of the rotating base (5), the electric cross bar (6) is fixedly connected to the side column (9) and can be rotated in a controlled manner, and the electric cross bar (6) is detachably connected to the sample holder (8) and drives it to flip.

2. The vacuum ion sputtering coating machine according to claim 1, wherein: The sealed housing comprises a vacuum cover (1), a column cover (3), and a base (13); the column cover (3) and the base (13) are respectively sealedly connected to the upper and lower ends of the vacuum cover (1); and the column cover (3) is connected to a target material (2), a vacuum pumping tube (10), a power line (11), and an argon gas pipeline (12).

3. The vacuum ion sputtering coating machine according to claim 1, wherein: The vacuum ion sputtering coating machine further comprises a hollow column (14), the top of the hollow column (14) being fixedly connected to the refrigeration device (7), and the bottom of the hollow column (14) being fixed on the base (13) of the sealed housing; a lifting column (4) being located inside the hollow column (14), the top of the lifting column (4) passing through a through hole on the refrigeration device (7) and being fixedly connected to the rotating base (5), and the bottom of the lifting column (4) being fixed on the base (13) of the sealed housing.

4. The vacuum ion sputtering coating machine according to claim 1, wherein: The number of the side columns (9) and the number of the electric cross bars (6) are both two, and they are symmetrically distributed on both sides of the rotating base (5); the electric cross bars (6) are telescopic or foldable.

5. The vacuum ion sputtering coating machine according to claim 1, wherein: A clamping slot (15) is provided on the sample clamp (8), and the electric crossbar (6) and the sample clamp (8) are fixed together through the clamping slot (15).

6. A method for continuous metallization of ultra-thin films using the vacuum ion sputtering coating machine according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: (a) fixing an ultra-thin film on a sample holder (8), placing the sample holder (8) on a rotating base (5) and covering it with a column cover (3) for sealing; (b) turning on the power, the lifting column (4) descending to a predetermined position and keeping rotating to complete uniform coating on one side of the ultra-thin film, during which the refrigeration device (7) dissipates heat for the rotating base (5) and the sample holder (8); (c) the lifting column (4) ascending to a predetermined position, the electric crossbar (6) of the flipping device extending out and locking into the sample holder; The lifting column (4) is lowered to make the sample clamp (8) leave the rotating base (5), and the turning device rotates to turn the sample clamp (8). After the lifting column (4) rises to the predetermined position, the electric cross bar (6) is retracted, and the sample clamp (8) returns to the rotating base (5); (d) the lifting column (4) descends to the predetermined position and keeps rotating to complete the uniform coating of the other side surface of the ultra-thin film. During this period, the refrigeration device (7) dissipates heat for the rotating base (5) and the sample clamp (8).

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