An anode conduction switching device for a magnetron sputtering apparatus

Abstract

The utility model provides an anode conductive switch device for magnetron sputtering equipment, including switch main part, switch main part is installed in the upper edge of plasma generating device, the switch main part includes conductive structure and elastic element, the upper and lower ends of conductive structure expose from the upper and lower end surface of plasma generating device upper edge, and have the downward movement tendency under the action of elastic element, the upper end of conductive structure is provided with ground wire installation hole. The utility model discloses the utility model, shorten the loop length, improve the electrical performance of equipment.

Description

Technical Field

[0001] This utility model relates to the field of physical vapor deposition equipment technology, and in particular to an anode conductive switch device for magnetron sputtering equipment. Background Technology

[0002] In physical vapor deposition (PVD) processes, an inert gas (such as argon) is filled into a vacuum chamber, and a high-power power supply (DC) is applied between the cathode (target) and the anode to generate plasma. Ions are accelerated under the influence of the electric field and bombard the cathode target, causing target atoms to be sputtered and deposited onto the silicon wafer surface to form a thin film.

[0003] In the design of PVD equipment, the entire system needs to form a closed loop. The cathode (target) is connected to a negative high voltage, and the anode (usually a cavity) needs to be connected to the grounding terminal of the power supply through a grounding loop. Electrons start from the cathode target, pass through the plasma, and finally need to flow to the anode to form a closed loop.

[0004] The current loop of the entire sputtering process is a closed loop that starts from the power source and eventually returns to it. Taking DC sputtering as an example, tracing the electron flow path (the current direction is opposite to the electron flow direction): 1. Starting point (power supply): The negative terminal (-) of the DC power supply is output through a high-voltage cable.

[0005] 2. Loading the target: Ar is ionized, and the positively charged argon ions are attracted to the target and accelerated to bombard the target surface, while electrons are repelled from the target surface and fly at high speed to the grounded cavity (anode).

[0006] During flight, electrons collide with argon molecules, ionizing them to produce new electrons and Ar⁺ ions, thus forming a conductive plasma. Electricity is actually conducted through the movement of electrons and ions within the plasma.

[0007] 3. Return path: After electrons reach the spare parts, adapter, and grounded cavity (anode), they are conducted through the metal structure of the cavity itself.

[0008] 4. End point (back to power): The ground wire guides the current from the cavity back to the positive (+) input terminal of the DC power supply, thus forming a complete closed loop.

[0009] Because the entire sputtering process involves a high-frequency, high-current discharge loop, the power supply output is not pure DC, especially during plasma ignition and arcing, where there are rapid current changes (di / dt). Any closed loop possesses parasitic inductance, and the magnitude of this inductance is directly proportional to the physical area of ​​the loop (the longer the loop path, the larger the enclosed area, and the greater the inductance). Therefore, the performance of the loop is crucial.

[0010] In existing technologies, the circuit is typically: power supply (-) → cable → target material → plasma → spare parts → adapter → cavity → support → ground busbar → power supply (+). Anode grounding is usually achieved through the cavity wall itself or an additional long grounding cable, resulting in an excessively long physical path for the anode grounding circuit.

[0011] Therefore, excessively long loops present the following problems: 1. Poor power supply stability and slow response: Traditional anode grounding paths are long, and each joint is a potentially high-resistance point, resulting in large parasitic inductance in the circuit. Large inductance resists rapid changes in current, causing slow power supply response and unstable plasma discharge, directly affecting the uniformity of thin film deposition.

[0012] 2. High voltage loss and low energy efficiency: A large loop inductance leads to energy loss (manifested as a higher holding voltage). To drive the same current, the power supply needs to provide additional voltage to overcome the inductive reactance (VL = L * di / dt). This voltage is ineffective and is dissipated as heat. The power supply must output a higher voltage to achieve the preset power, reducing energy utilization and increasing operating costs.

[0013] 3. Limiting Maximum Power and Deposition Rate: At high power, the current is very large, and the negative effects of inductance (voltage loss, stability issues) become more significant. This effectively limits the upper limit of power that the equipment can safely and stably operate at. It also prevents the use of higher power to increase the deposition rate, impacting production efficiency.

[0014] 4. Exacerbating Arcing and Degrading Thin Film Quality: Tiny protrusions or contaminants on the target surface can lead to charge accumulation, eventually causing breakdown and arcing. An arc is essentially a momentary short-circuit event with a sharp increase in current (a huge di / dt). High loop inductance generates extremely high reverse voltage (L * di / dt) during arcing, which prolongs the arc's duration and intensifies its strength. A strong arc can sputter large molten particles into the thin film, creating defects. In severe cases, it can also severely damage the target surface, forming molten pits, leading to more frequent arcing, creating a vicious cycle. Utility Model Content

[0015] To address the aforementioned problems, this utility model discloses an anode conductive switch device for magnetron sputtering equipment, comprising a switch body mounted on the upper edge of a plasma generator. The switch body includes a conductive structure and an elastic element. The upper and lower ends of the conductive structure protrude from the upper and lower end faces of the upper edge of the plasma generator, and under the action of the elastic element, the conductive structure has a downward tendency. A ground wire mounting hole is provided at the upper end of the conductive structure. The conductive structure shortens the circuit, and the elastic element ensures good contact at the lower end of the conductive structure.

[0016] Preferably, the elastic element is a cylindrical spring, with one end of the spring abutting the upper edge of the plasma generator and the other end abutting the lower part of the conductive structure. Other elastic elements besides a cylindrical spring, such as a spring sheet, can also be used.

[0017] Preferably, the conductive structure includes a first conductive portion at the bottom and a second conductive portion at the top, with a conductive post electrically connected between the first and second conductive portions, and the first conductive portion, the second conductive portion, and the conductive post are all accommodated in slots on the upper edge of the plasma generator. This three-section structure facilitates its installation and fixation in the upper edge of the plasma generator.

[0018] Preferably, the first conductive part, the second conductive part, and the conductive post are all made of copper or a copper alloy. The selection of this type of material ensures conductivity.

[0019] Preferably, at least two vertical stainless steel screws are symmetrically arranged on both sides of the first conductive part. The screws have smooth surfaces and slide in a pre-set countersunk hole on the upper edge of the plasma generator. The lower end of the screw has a threaded section, which fits into a pre-set threaded hole on the first conductive part. The larger diameter of the upper end of the screw fits into the larger hole of the countersunk hole, thus fixing the first conductive part. In addition, the vertical sliding fit prevents the first conductive part from tilting when the plasma generator operates, thereby providing conductivity.

[0020] Preferably, the second conductive part has a fixing hole starting from the middle of its upper end, and the upper end of the conductive post is provided with a second threaded hole, with a bolt pre-set in the fixing hole and the second threaded hole engaging. The lower end of the conductive post is provided with a threaded section, which engages in a first threaded hole pre-set on the first conductive part. This achieves a fixed connection between the conductive post and the first conductive part and the second conductive part, respectively.

[0021] Preferably, the lower end face of the first conductive part is provided with a groove, and a flexible conductive ring is accommodated in the groove, with the conductive ring protruding from the lower end face of the first conductive part. This allows the conductive ring to make pre-contact with the adapter below, ensuring electrical performance.

[0022] Preferably, the conductive ring is a Spiral spiral tube. The Spiral spiral tube is a high-performance electromagnetic shielding gasket. Made of beryllium copper / stainless steel, it possesses excellent elasticity and resistance to permanent compression deformation. Tin plating further enhances its conductivity and shielding performance. The edge-coated gasket exhibits strong resistance to electrochemical corrosion in humid and smoky environments. The conductivity of the Spiral spiral tube is utilized here.

[0023] A magnetron sputtering apparatus includes a cavity, an adapter fixed to the upper end of the cavity, a plasma generator located above the adapter, a bracket rotatably mounted in the cavity, the plasma generator being fixed to the bracket, a conductive switch connected to the upper edge of the plasma generator, and the lower end face of the upper edge of the plasma generator being attached to the upper end of the adapter.

[0024] The beneficial effects of this utility model are as follows: 1. Significantly reduced loop resistance and inductance: By directly integrating the grounding port and connecting it near the adapter, long cables and multiple connection points are eliminated, resulting in a significant reduction in loop resistance and inductance, and improved power supply response speed and process stability.

[0025] 2. Effective arc suppression: The low inductance circuit helps to quickly extinguish the arc on the target surface, reduce thin film defects, and improve product yield.

[0026] 3. Improve energy efficiency: Reduce energy loss caused by loop impedance, allowing the same process power to be maintained at a lower voltage, thus saving energy and reducing consumption.

[0027] 4. Integration and safety: As part of the target material, the conductive switch device can automatically switch between "power off when the cover is open and power on when the cover is closed" without any additional operation. It is safe and convenient and avoids human error.

[0028] 5. Ensure contact reliability: The flexible Spiral spiral tube design ensures the uniformity, stability and reliability of the contact surface when a large current passes through. Attached Figure Description

[0029] Figure 1 This is a three-dimensional schematic diagram of the equipment used in the application of this utility model; Figure 2 This is a three-dimensional schematic diagram of the present invention; Figure 3 This is a cross-sectional view of the present invention.

[0030] List of reference numerals in the attached diagram: 1. Cavity; 2. Adapter; 3. Plasma generator; 4. Switch body; 5. Support; 41. First conductive part; 42. Screw; 43. Elastic element; 44. Conductive post; 45. Second conductive part; 46. Grounding mounting hole; 47. Fixing hole; 48. First threaded hole; 49. Second threaded hole. Detailed Implementation

[0031] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only for illustrating the present invention and are not intended to limit the scope of the present invention. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to the directions in the accompanying drawings, and the terms "inner" and "outer" refer to the directions toward or away from the geometric center of a specific component, respectively.

[0032] like Figure 1 As shown, a magnetron sputtering apparatus includes a cavity 1, an adapter 2 fixed to the upper end of the cavity 1, a plasma generator 3 located above the adapter 2, and a support 5 rotatably mounted on the cavity 1. The plasma generator 3 is fixed to the support 5, and a conductive switch is connected to the upper edge of the plasma generator 3, with the lower end face of the upper edge of the plasma generator 3 abutting against the upper end of the adapter 2. The conductive switch is used to shorten the circuit and improve the electrical performance of the apparatus.

[0033] like Figures 1 to 3 As shown, an anode conductive switch device for a magnetron sputtering apparatus includes a switch body 4, which is mounted on the upper edge of a plasma generator 3. The switch body 4 includes a conductive structure and an elastic element 43. The upper and lower ends of the conductive structure protrude from the upper and lower end faces of the upper edge of the plasma generator 3, and the conductive structure tends to move downward under the action of the elastic element 43. A ground wire mounting hole 46 is provided at the upper end of the conductive structure. The elastic element 43 ensures that the conductive structure and the adapter 2 below it are in close contact.

[0034] The elastic element 43 is a cylindrical spring, with one end abutting the upper edge of the plasma generator 3 and the other end abutting the lower part of the conductive structure. The use of a cylindrical spring has the advantages of simple structure, relatively regular shape, and ease of use.

[0035] The conductive structure includes a first conductive part 41 located at the bottom and a second conductive part 45 located at the top. A conductive post 44 is electrically connected between the first conductive part 41 and the second conductive part 45. The first conductive part 41, the second conductive part 45 and the conductive post 44 are all accommodated in a slot at the upper edge of the plasma generator 3.

[0036] The first conductive part 41, the second conductive part 45, and the conductive post 44 are all made of copper or copper alloy.

[0037] At least two vertical stainless steel screws 42 are symmetrically arranged on both sides of the first conductive part 41. The screws 42 have smooth surfaces and slide in the countersunk holes pre-set on the upper edge of the plasma generator 3. The lower end of the screw 42 has a threaded section, which fits in the first threaded hole 48 pre-set on the first conductive part 41. The screws 42 not only limit the position of the first conductive part 41, but also ensure the force balance of the first conductive part 41, ensuring that the first conductive part 41 can slide vertically and preventing the first conductive part 41 from tilting when the plasma generator 3 is activated.

[0038] The upper middle part of the second conductive part 45 has a fixing hole 47, which is also a countersunk hole. The upper end of the conductive post 44 is provided with a second threaded hole 49, and the bolt preset in the fixing hole 47 and the second threaded hole 49 are engaged. The lower end of the conductive post 44 is provided with a threaded section, and the threaded section is engaged in the first threaded hole 48 preset on the first conductive part 41.

[0039] A groove is provided on the lower end face of the first conductive part 41, and a flexible conductive ring is accommodated in the groove, with the conductive ring protruding from the lower end face of the first conductive part 41. The conductive ring is a Speyer spiral tube. The Speyer spiral tube improves the conductivity between the first conductive part 41 and the adapter 2.

[0040] When the equipment is running, an electrical path with extremely low impedance is formed: adapter 2 (anode potential) → switch body 4 → ground wire → power supply (+).

[0041] The technical means disclosed in this utility model are not limited to the technical means disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features.

Claims

1. An anode conduction switching device for a magnetron sputtering apparatus, comprising a switching body (4) mounted on the upper edge of a plasma generating device (3), characterized in that: The switch body (4) includes a conductive structure and an elastic element (43). The upper and lower ends of the conductive structure are exposed from the upper and lower end faces of the plasma generator (3). Under the action of the elastic element (43), the conductive structure has a downward movement tendency. The upper end of the conductive structure is provided with a ground wire mounting hole (46).

2. The anode conductive switch device for a magnetron sputtering equipment according to claim 1, characterized in that: The elastic element (43) is a cylindrical spring, with one end of the cylindrical spring abutting against the upper edge of the plasma generator (3) and the other end abutting against the lower part of the conductive structure.

3. The anode conductive switch device for a magnetron sputtering equipment according to claim 1, characterized in that: The conductive structure includes a first conductive part (41) at the bottom and a second conductive part (45) at the top. A conductive post (44) is electrically connected between the first conductive part (41) and the second conductive part (45). The first conductive part (41), the second conductive part (45) and the conductive post (44) are all housed in a slot at the upper edge of the plasma generator (3).

4. The anode conductive switch device for a magnetron sputtering equipment according to claim 3, characterized in that: The first conductive part (41), the second conductive part (45) and the conductive post (44) are all made of copper or copper alloy.

5. The anode conductive switch device for a magnetron sputtering equipment according to claim 3, characterized in that: At least two vertical stainless steel screws (42) are symmetrically arranged on both sides of the first conductive part (41). The surface of the screws (42) is smooth and they slide in the countersunk hole at the upper edge of the plasma generator (3). The lower end of the screws (42) is provided with a threaded section, and the threaded section fits in the first threaded hole (48) on the first conductive part (41).

6. The anode conductive switch device for a magnetron sputtering equipment according to claim 3, characterized in that: The upper middle part of the second conductive part (45) has a fixing hole (47), the upper end of the conductive post (44) is provided with a second threaded hole (49), and the bolt preset in the fixing hole (47) and the second threaded hole (49) cooperate. The lower end of the conductive post (44) is provided with a threaded section, and the threaded section cooperates in the first threaded hole (48) preset on the first conductive part (41).

7. The anode conductive switch device for a magnetron sputtering equipment according to claim 3, characterized in that: The lower end face of the first conductive part (41) is provided with a groove, and a flexible conductive ring is accommodated in the groove, and the conductive ring protrudes from the lower end face of the first conductive part (41).

8. The anode conductive switch device for a magnetron sputtering equipment according to claim 7, characterized in that: The conductive ring is made of Spire spiral tube.

9. A magnetron sputtering apparatus, comprising a cavity (1), an adapter (2) fixed to the upper end of the cavity (1), a plasma generator (3) located above the adapter (2), and a bracket (5) rotatably disposed in the cavity (1), wherein the plasma generator (3) is fixed on the bracket (5), and an anode conductive switch device for a magnetron sputtering apparatus according to any one of claims 1-8, characterized in that: The conductive switch is connected to the upper edge of the plasma generator (3), and the lower end face of the upper edge of the plasma generator (3) is attached to the upper end of the adapter (2).

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