Sectional type filamentous target material suitable for sputter coating of inner wall of long and thin pipe

Abstract

The invention discloses a sectional type filiform target material suitable for sputter coating of the inner wall of a long and thin pipe. The sectional type filiform target material comprises a conductive wire and a plurality of cylindrical target material units which are arranged on the conductive wire in a sleeving mode and provided with through holes in the middles. The slender structure of the sectional type filamentous target material can better adapt to the internal space of a small-caliber pipe fitting and is particularly suitable for coating the inner wall of a small-caliber and large-length-diameter-ratio pipe fitting, the target material is divided into the multiple filamentous units capable of being independently controlled, the precision of film layer component control and the material utilization rate are improved, and the production cost is reduced. The design flexibility, the material utilization rate and the coating uniformity are remarkably improved, meanwhile, preparation of composite coatings and functional gradient coatings is supported, and the method has wide application prospects in the fields of semiconductor manufacturing, optical coating, surface protection coatings and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of general plating technology of vacuum evaporation method, sputtering method, ion implantation method or chemical vapor deposition method, and particularly relates to a segmented filament target suitable for sputtering film on the inner wall of an elongated pipe. BACKGROUND

[0002] The sputtering film technology on the inner wall of a pipe is an important surface treatment technology, which is widely used in the fields of microelectronics, optics, medical devices and aerospace, etc. The technology uses high-energy particles to bombard the target in a vacuum environment, so that the atoms or molecules of the target are sputtered and deposited on the surface of the inner wall of the pipe to form a dense and uniform functional coating. When the inner wall of a small-caliber pipe with a large length-diameter ratio (inner diameter less than 15 mm and length-diameter ratio greater than 75) is plated, the traditional target, especially the target with high brittleness, is difficult to achieve plating. The application provides a segmented filament target with higher spatial adaptability and flexibility, which can meet the plating requirements of the inner wall of an elongated pipe. SUMMARY

[0003] The application solves the technical problems in the prior art, provides a segmented filament target suitable for sputtering film on the inner wall of an elongated pipe, and significantly improves the flexibility, material utilization rate and coating uniformity of the target through modular design and independent control units, while realizing the preparation of a composite coating and a functional gradient coating on the inner wall of a small-caliber pipe with a large length-diameter ratio, and providing an efficient and precise solution for plating the inner wall of a small-caliber pipe with a large length-diameter ratio.

[0004] To solve the above technical problems, the technical solution provided by the application is as follows: A segmented filament target suitable for sputtering film on the inner wall of an elongated pipe is provided, which comprises a conductive wire and a plurality of intermediate cylindrical target units with holes on the conductive wire.

[0005] According to the above scheme, the conductive wire is made of titanium (Ti), zirconium (Zr), iron (Fe), aluminum (Al) or copper (Cu), the diameter of the conductive wire is 1-2 mm, the length is 500-1500 mm, and the shape of the conductive wire can be adjusted as needed, which can be straight, curved or wavy.

[0006] According to the above scheme, the target unit is made of metal or alloy, the metal is chromium (Cr), titanium (Ti), tantalum (Ta) or aluminum (Al), and the alloy is TiAl alloy, TiSi alloy, CrAl alloy or TiCr alloy.

[0007] According to the above scheme, the materials of each target unit on the conductive wire are the same or different. When the materials of each target unit are different, the deposition of a multi-element composite coating can be realized by combining target units with different materials.

[0008] According to the above scheme, the inner diameter (diameter) of the target material unit is the same as the diameter of the conductive wire, the outer diameter is 3-5 mm, and the height is 10-100 mm.

[0009] According to the above scheme, the inner diameters of the target material units on the conductive wire are the same, and the outer diameters are the same or different. In the case of different outer diameters, the outer diameters of the target material units gradually increase or decrease from one end of the conductive wire to the other end, or first increase and then decrease, or first decrease and then increase. In the case that the materials of the target material units on the conductive wire are the same, when the outer diameters of the target material units gradually increase, the film thickness on the inner wall of the pipe gradually thins; when the outer diameters of the target material units gradually decrease, the film thickness on the inner wall of the pipe gradually thickens; when the outer diameters of the target material units first increase and then decrease, the film thickness on the inner wall of the pipe first decreases and then increases; when the outer diameters of the target material units first decrease and then increase, the film thickness on the inner wall of the pipe first increases and then decreases.

[0010] According to the above scheme, the target material units on the conductive wire are in close contact.

[0011] According to the above scheme, the target material units on the conductive wire are arranged at an interval according to needs, and the interval is equal or unequal. In the case that the target material units are arranged at an interval, the conductive wire itself can also be used as a target material for sputtering film coating.

[0012] According to the above scheme, a support frame is further arranged on the conductive wire, the support frame is installed at both ends of the conductive wire, and is used to fix and support the conductive wire and the target material units in the pipe, and can move along the inner wall of the pipe.

[0013] The preparation method of the above segmented wire-shaped target material is as follows: a cylindrical target material unit with a through hole in the middle is prepared, then the conductive wire is passed through the cylindrical target material unit, and the cylindrical target material unit is fixed on the conductive wire according to needs, to obtain the segmented wire-shaped target material.

[0014] The application also includes a method for sputtering film coating on the inner wall of a pipe by using the above segmented wire-shaped target material, and the specific steps are as follows: the segmented wire-shaped target material is put into the pipe, and the pipe is placed in the cavity of a magnetron sputtering device, the inside of the pipe is vacuumized to a background vacuum, a sputtering gas is introduced, the gas pressure inside the pipe is maintained at 1-2 Pa, the magnetic field strength inside the pipe is controlled to be 100-1000 Gass, the sputtering voltage is 100-600 V, the current is 0.1-5 A, the frequency is 10-50 kHz, and the sputtering time is 1-20 h, to sputter and coat the inner wall of the pipe.

[0015] The utilization rate of the edge region of the traditional target material is low in the sputtering process, which affects the overall use efficiency of the material. In addition, for small caliber and large length-diameter ratio elongated pipes, the traditional target material has certain challenges in coating thickness, performance uniformity control and functional gradient coating preparation, and it is difficult to meet the high-precision coating requirements (due to the limitations in flexibility, material utilization rate and coating uniformity control, it is difficult to realize the deposition of uniform and dense composite coating and functional gradient coating on the inner wall). The freely adjustable segmented filament target provided by the present application adopts a modular design concept, which divides the traditional whole target into multiple independent filament units, the size and position of each unit can be individually adjusted, thereby realizing flexible design and accurate control of the target structure, and the segmented filament target can be composed of multiple target units with different materials or compositions through precise connection technology, which breaks through the limitations of traditional target materials, can flexibly design the material composition and geometric shape of the target according to the specific process requirements, significantly improves the adaptability and functionality of the target, and realizes accurate deposition of multi-element composite coating and gradient coating. In addition, the segmented filament target can also optimize the material utilization rate through close arrangement to reduce production cost. At the same time, by independently adjusting the sputtering power and position of each filament unit, the plasma distribution can be optimized, the sputtering rate and the density of the film layer can be improved, thereby effectively improving the uniformity of the coating thickness and performance.

[0016] The beneficial effects of the present application are: 1. The segmented filament target provided by the present application has an elongated structure which can better adapt to the internal space of small caliber pipes, especially for the inner wall coating of small caliber and large length-diameter ratio pipes. By dividing the target into multiple independently controllable filament units, the precision of film layer composition control and material utilization rate are improved, the design flexibility, material utilization rate and coating uniformity are significantly improved, and the preparation of composite coating and functional gradient coating is supported, which has broad application prospects in the fields of semiconductor manufacturing, optical coating and surface protection coating. 2. The preparation process of the segmented filament target has high yield, which can reduce material waste and improve production efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a schematic diagram of the main structure of the segmented filament target described in embodiment 1 of the present application; Figure 2 It is a schematic diagram of the magnetron sputtering installation of the segmented filament target of embodiment 1; Figure 3 It is a scanning electron microscope (SEM) image of the film layer obtained in embodiment 1; Figure 4 It is a scanning electron microscope image of the film layer obtained in embodiment 2; Figure 5 It is a schematic diagram of the segmented filament target with different structures in embodiment 3. DETAILED DESCRIPTION

[0018] In order for those skilled in the art to better understand the technical solutions of the present application, the present application will be described in further detail below with reference to the accompanying drawings.

[0019] Example 1 A segmented filament target suitable for sputtering coating on the inner wall of an elongated pipe, a schematic diagram of the main structure thereof is shown in Figure 1 which includes a Zr filament 2 (length 1200 mm, diameter 1 mm) and 10 intermediate hole-passing cylindrical Cr target units 1 (length 100 mm, inner diameter 1 mm, outer diameter 3 mm) sleeved on the Zr filament, each Cr target unit is tightly connected, and a support frame is further provided at both ends of the Zr filament.

[0020] The preparation method of the above-mentioned segmented filament target is as follows: a conventional commercially available Cr target is selected, and 10 cylinders with a diameter of 3 mm and a height of 100 mm are processed therefrom by using a grinding tool and a sintering process, a hole passing through the center of the cylinder is precisely drilled by using a drill bit with a diameter of 1 mm, thereby obtaining a hole-passing cylindrical Cr target unit, and finally, a Zr filament with a diameter of 1 mm is used to sequentially pass through the holes in the hole-passing cylindrical Cr target units, thereby obtaining the segmented filament target.

[0021] Referring to the magnetron sputtering device and coating method of CN119824380A, the above-mentioned segmented filament target is fixedly installed in a pipe 3 (stainless steel material, inner diameter 12.7 mm, outer diameter 14 mm, length 1000 mm) as shown in Figure 2 The two ends of the Zr filament are connected with vacuum electrodes and a cooling system 6, the pipe is sealed, and an inlet 4 and an outlet 5 are respectively arranged on the two vacuum electrodes, an inlet 7 and an outlet 8 are further arranged on the vacuum electrodes, then the pipe 3 is placed in the middle of an electromagnetic coil, a vacuum pump is started to vacuumize the inside of the pipe, so that the internal vacuum degree reaches less than 10 -4 Pa order of magnitude, then argon gas is introduced through the inlet 4 (flow rate 75 sccm) to maintain the gas pressure in the pipe at 2 Pa, a direct current power supply of the electromagnetic coil is started, the current is set to 100 A, the magnetic field strength in the parallel direction of the surface of the target material reaches 300 Gauss, the direct current sputtering power supply voltage is set to 500 V, the sputtering time lasts for 5 hours, and water is introduced from the inlet 4 for cooling at the same time of sputtering, and finally the sputtering coating is formed on the inner wall of the pipe.

[0022] The cross section of the film layer (Cr coating) obtained in this embodiment is tested by a scanning electron microscope, and the result is shown in Figure 3 As can be seen from the figure, the surface of the film layer is flat, the cross section has no holes, the structure is dense, the interface between the film layer and the pipe is tightly combined, and the overall uniformity is good.

[0023] Example 2 A segmented filamentary target material suitable for sputtering coating on the inner wall of slender tubes includes a Zr wire 2 (1200 mm in length and 1 mm in diameter) and 10 cylindrical Cr target material units 1 (100 mm in length, 1 mm in inner diameter, and 3 mm in outer diameter) with through holes in the middle, which are sleeved on the Zr wire. The Ti target material units are tightly connected, and a support frame is provided at both ends of the Zr wire. The segmented filamentous target material described above is fixedly installed inside the tube 3 (stainless steel, inner diameter 12.7 mm, outer diameter 14 mm, length 1000 mm) according to the method in Example 1. Both ends of the Zr wire are connected to the vacuum electrode and cooling system 6. The tube is sealed, and air inlets 4 and outlets 5 are respectively provided on the vacuum electrodes at both ends. Water inlets 7 and outlets 8 are also provided on the vacuum electrodes. Then, the tube 3 is placed in the middle of the electromagnetic coil, and the vacuum pump is started to evacuate the inside of the tube until the internal vacuum level reaches less than 10. -4 The pressure is in the Pa range. Argon (flow rate 60 sccm) and nitrogen (flow rate 15 sccm) are then introduced through inlet 4 to maintain the gas pressure inside the tube at 2 Pa. The DC power supply of the electromagnetic coil is started and the current is set to 100 A to make the magnetic field strength in the parallel direction of the target surface reach 300 Gauss. The DC sputtering power supply voltage is set to 500 V and the sputtering time lasts for 5 hours. Water is introduced through inlet 4 for cooling during sputtering. Finally, a film is sputtered onto the inner wall of the tube.

[0024] Scanning electron microscopy was performed on the cross-section of the film (CrN coating) obtained in this embodiment, and the results are as follows: Figure 4 As shown in the figure, the membrane surface is flat, the cross-section is free of pores, the structure is dense, and the membrane is tightly bonded to the pipe interface, with good overall uniformity.

[0025] Example 3 Based on actual sputtering requirements, segmented filamentary targets with different structures are designed, as shown in the structural diagram below. Figure 5 As shown, a segmented filamentous target composed of target units with gradually increasing outer diameters has a coating thickness that gradually decreases on the inner wall of the tube; a segmented filamentous target composed of target units with gradually increasing and then decreasing outer diameters has a coating thickness that first decreases and then increases on the inner wall of the tube; a segmented filamentous target composed of target units of different materials can obtain a coating with composite components; a segmented filamentous target composed of target units spaced at a certain distance (where the exposed conductive wire is part of the target) can obtain a coating with composite components.

[0026] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A segmented filamentary target suitable for sputtering coating on the inner wall of slender tubes, characterized in that, It comprises a conductive wire and a plurality of intermediate belt hole cylindrical target material units sleeved on the conductive wire.

2. The segmented wire target according to claim 1, wherein, The conductive wire is made of titanium, zirconium, iron, aluminum or copper, the diameter of the conductive wire is 1-2mm, the length is 500-1500mm, and the shape of the conductive wire can be adjusted as needed.

3. The segmented wire target of claim 1, wherein, The target material unit is made of metal or alloy, the metal is chromium, titanium, tantalum or aluminum, and the alloy is TiAl alloy, TiSi alloy, CrAl alloy or TiCr alloy.

4. The segmented wire target of claim 1, wherein, The materials of the target material units on the conductive wire are the same or different.

5. The segmented wire target of claim 1, wherein, The inner diameter of the target material unit is the same as the diameter of the conductive wire, the outer diameter is 3-5mm, and the height is 10-100mm.

6. The segmented wire target of claim 1, wherein, The inner diameters of the target material units on the conductive wire are the same, and the outer diameters are the same or different, in the case of different outer diameters, the outer diameters of the target material units gradually increase or decrease from one end of the conductive wire to the other end, or first increase and then decrease, or first decrease and then increase.

7. The segmented wire target of claim 1, wherein, The target material units on the conductive wire are in close contact, or the target material units on the conductive wire are arranged at an equal interval or a non-equal interval according to the need.

8. The segmented wire target of claim 1, wherein, The conductive wire is also provided with a support frame installed at both ends of the conductive wire for fixing and supporting the conductive wire and the target material unit in the pipe material and can move along the inner wall of the pipe material.

9. A method for producing a segmented wire target suitable for sputter coating the interior wall of an elongated tube as claimed in any one of claims 1 to 8, characterized in that: The intermediate belt hole cylindrical target material unit is prepared, then the conductive wire is passed through the cylindrical target material unit and the cylindrical target material unit is fixed on the conductive wire as needed to obtain a segmented wire target material.

10. A method of sputter coating the inner wall of a pipe with the segmented wire target of any one of claims 1 to 8, characterized in that, The specific steps are as follows: the segmented wire target material is put into the pipe material, and the pipe material is placed in the cavity of the magnetron sputtering device, the inside of the pipe material is vacuumized to the background vacuum, the sputtering gas is introduced, the internal gas pressure of the pipe material is maintained at 1-2Pa, the magnetic field strength in the pipe material is controlled at 100-1000Gass, the sputtering voltage is 100-600V, the current is 0.1-5A, the frequency is 10-50kHz, and the sputtering time is 1-20h.

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