Compatible plasma cleaning cavity and plasma processing equipment

Abstract

The invention discloses a compatible plasma cleaning cavity and plasma processing equipment, the plasma cleaning cavity comprises a cavity body formed by sequentially connecting a sample cavity, a plasma generation cavity and a gas inlet cavity, and a gas uniformizing device is arranged between the gas inlet cavity and the plasma generation cavity; the gas uniformizing device comprises a lower gas uniformizing vessel, an outer shade ring and an inner shade ring which are sequentially and coaxially arranged from bottom to top, a plurality of gas uniformizing areas are formed in a top plate of the lower gas uniformizing vessel in the radial direction, and opening or closing of the gas uniformizing areas is adjusted by adjusting the positions of the outer shade ring and the inner shade ring. And adjusting the position of the process gas entering the plasma generation cavity and the partition flow. The gas uniformizing device is arranged between the gas inlet cavity and the plasma generating cavity, process gas enters the plasma generating cavity after being subjected to two-section gas uniformizing, gas rarefaction positions are different, plasma energy density distribution is different, the plasma uniformizing device is suitable for to-be-cleaned workpieces of different sizes, and energy waste is avoided.

Description

Technical Field

[0001] This invention relates to the field of plasma cleaning equipment technology, and in particular to a compatible plasma cleaning chamber and plasma processing equipment. Background Technology

[0002] Plasma cleaning equipment, as an advanced dry surface treatment technology, operates on the core principle of ionizing process gases (such as argon and oxygen) under a specific energy field (such as radio frequency or microwave) to generate plasma containing highly reactive particles (such as ions, electrons, free radicals, and excited-state molecules). These high-energy particles act on the material surface through physical bombardment (momentum transfer) and chemical reactions (such as oxidation and reduction reactions), thereby achieving non-contact cleaning, activation, and modification. With its superior cleaning and modification capabilities, excellent environmental characteristics, and adaptability to complex micro- and nano-structures, plasma cleaning has become a key process driving the development of cutting-edge manufacturing industries such as semiconductors and high-end packaging.

[0003] With technological advancements, higher demands are being placed on the uniformity and efficiency of plasma cleaning equipment: firstly, it must be able to handle workpieces of different sizes and materials; secondly, the equipment must have a higher degree of automation to reduce time loss and contamination risks caused by manual intervention. Specifically: Currently, commonly used plasma cleaning equipment is designed for fixed-size parts. Within a fixed plasma cleaning chamber, when the RF power is constant, the overall energy density of the generated plasma is relatively stable under given process conditions. That is, regardless of the size of the part, the energy of the plasma in the same plasma cleaning equipment is fixed. For cleaning small workpieces, if an unoptimized, uniformly distributed plasma suitable for large sizes is still used, only the plasma directly above the workpiece is effectively utilized, while the plasma energy in the surrounding space (or edge regions) bombards the empty base or chamber walls, resulting in energy waste. Simultaneously, the edges of small workpieces may experience over-etching or uneven cleaning due to the plasma sheath boundary effect. Conversely, for cleaning large workpieces, if an unoptimized, uniformly distributed plasma suitable for small sizes is still used, the edge regions of large workpieces will not be thoroughly cleaned.

[0004] In addition, when using existing plasma cleaning equipment, the workpiece to be cleaned needs to frequently enter and exit through the transfer port opened in the cleaning chamber. The sealing of the transfer port and the large space of the cleaning chamber will affect the efficiency of the plasma. At the same time, the plasma will also cause sputtering pollution and energy waste in the lower chamber of the cleaning chamber. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention aims to provide a plasma cleaning chamber and plasma processing equipment that are highly compatible and efficient.

[0006] The technical solution of the present invention is as follows: A compatible plasma cleaning chamber includes a cavity consisting of a sample chamber, a plasma generating chamber, and an inlet chamber connected in sequence. A gas equalization device is provided between the inlet chamber and the plasma generating chamber. The gas equalization device includes a lower gas equalization dish, an outer shielding ring, and an inner shielding ring arranged coaxially from bottom to top. Multiple gas equalization areas are radially formed on the top plate of the lower gas equalization dish. The opening or closing of each gas equalization area is adjusted by adjusting the position of the outer shielding ring and the inner shielding ring, thereby adjusting the position and zone flow rate of the process gas entering the plasma generating chamber.

[0007] In a further embodiment, the outer wall of the lower gas equalizing dish is fixed to the inner wall of the plasma generating cavity, and the outer shielding ring and the inner shielding ring are rotatably disposed on the top surface of the lower gas equalizing dish.

[0008] In a further embodiment, the lower gas equalization dish is a cylindrical structure with a top plate fixed at its top opening; the top plate is provided with gas equalization holes, the gas equalization holes located at the center of the top plate form a central gas equalization area, and the gas equalization holes located on the outer periphery of the central gas equalization area and distributed in a fan-shaped pattern form an outer gas equalization area.

[0009] In a further embodiment, the outer shielding ring includes an outer ring body, and the inner ring body is provided with inner protrusions at equal intervals along the circumference. The inner shielding ring includes an inner ring body, and the outer surface of the inner ring body is provided with external protrusions at equal intervals along the circumference. When the inner shielding ring is coaxially fitted at the center of the outer shielding ring, and the outer protrusion is aligned with the inner protrusion or located in the gap between two adjacent inner protrusions, the outer uniform air area is fully shielded, unshielded, or partially shielded to form three uniform air states.

[0010] In a further embodiment, in order to protect the lower part of the sample chamber and improve plasma utilization, a chuck for carrying the workpiece to be cleaned is provided inside the sample chamber, and a shielding bottom cover is movably installed inside the sample chamber located on the outer periphery of the chuck. The shielding bottom cover moves up and down along the inner wall of the sample chamber.

[0011] In a further embodiment, a transfer port is provided on one side of the sample chamber for the entry and exit of the workpiece to be cleaned; The bottom of the shielding cover is connected to a lifting mechanism to drive the shielding cover to move up and down; when the shielding cover is lowered into position, its bottom surface is flush with the top surface of the chuck, completely covering the lower part of the transfer port and the sample chamber; when the shielding cover is raised into position, its bottom surface is flush with the upper wall of the transfer port, making room for the transfer channel of the workpiece to be cleaned.

[0012] In a further embodiment, the inner wall of the sample chamber is fixed with an n-shaped groove for locking the top of the shielding cover. When the shielding cover is raised to the position, its top is embedded in the n-shaped groove. And / or, The lifting mechanism includes a lifting column connected to the bottom end of the shielding cover. The lifting column is connected to a push-pull mechanism. A second telescopic bellows is sleeved on the lifting column. The top end of the second telescopic bellows is fixed to the bottom end face of the sample chamber for sealing.

[0013] In a further embodiment, an exhaust hood is provided around the chuck and the shielding base, and the exhaust hood is provided with exhaust holes evenly distributed on it.

[0014] In a further embodiment, the sample chamber is provided with a chuck for carrying the workpiece to be cleaned, and a biasing ring is nested in the lower groove on the outer periphery of the chuck. And / or, The bias ring is connected to the RF power supply in sequence through the RF feedthrough and RF matching unit, so that the bias ring generates a self-bias voltage to attract and accelerate the plasma to bombard the surface of the chuck.

[0015] In a further embodiment, a shielding ring is fixedly provided on the top surface of the bias ring.

[0016] In a further embodiment, the air inlet chamber includes an upper cover plate fixed to the plasma generating chamber with an opening. The upper cover plate has a process gas port, which is connected to the process gas in sequence through an air inlet pipe and a flow meter.

[0017] In a further embodiment, to improve the uniformity of cleaning, a movable base is provided at the bottom of the sample chamber. The movable base includes a chuck located inside the sample chamber for supporting the workpiece to be cleaned, and a drive mechanism for driving the chuck to move up and down or rotate within the sample chamber.

[0018] In a further embodiment, the driving mechanism includes a rotating shaft connected to the chuck, with a lifting mechanism and a rotating mechanism connected to the ends of the rotating shaft, which are used to drive the chuck to move up and down or rotate within the sample chamber; a supporting flange is movably sleeved on the rotating shaft, and the supporting flange is fixed to the bottom end face of the sample chamber for sealing. And / or, An elastic pin is abutted against the outer wall of the rotating shaft. The elastic pin is connected to the ESC power supply through a vacuum power supply, and the current is fed into the movable chuck through the rotating shaft, so that the surface of the chuck generates static electricity to adsorb the workpiece to be cleaned.

[0019] In a further embodiment, a vacuum pumping device is installed on the sample chamber; And / or, A lifting mechanism is installed on the outer wall of the sample chamber, and the lifting mechanism is connected to the plasma generating chamber for raising and lowering the plasma generating chamber.

[0020] Another objective of this invention is to provide a plasma processing apparatus that includes the aforementioned compatible plasma cleaning chamber, i.e., a cleaning chamber used in the plasma processing apparatus for pre-cleaning the workpiece. In use, the plasma cleaning chamber of this invention is connected to the plasma processing apparatus to first remove impurities such as oxides from the surface of the workpiece, such as a wafer, before performing a deposition process to prepare a magnetic thin film.

[0021] The present invention has the following advantages over the prior art: This invention incorporates a gas equalization device between the inlet chamber and the plasma generation chamber. After the process gas enters the inlet chamber, it undergoes free diffusion, completing the first stage of gas equalization. Then, it slowly and evenly enters the plasma generation chamber through the equalization device, completing the second stage of gas equalization. This improves the uniformity of the process gas.

[0022] The gas equalization device in this invention adjusts the opening or closing of each gas equalization area by adjusting the positions of the outer shielding ring and the inner shielding ring, forming three gas equalization positions. The process gas enters the plasma generation chamber after passing through the three different positions on the gas equalization device, resulting in different gas rarefaction positions in the plasma generation chamber and different distributions of excited plasma energy density. Therefore, it can be applied to workpieces of different sizes to be cleaned, avoiding energy waste.

[0023] This invention features a liftable and movable shielding cover at the bottom of the sample chamber. This cover not only completely shields the transfer port and the lower part of the sample chamber, preventing direct plasma bombardment of the metal inner wall of the sample chamber and causing contamination, but also prevents eddy currents from generating radio frequency energy loss. Furthermore, the shielding cover can be raised to create a transfer channel for cleaning the workpiece.

[0024] The present invention has an exhaust hood arranged in a ring between the chuck and the shielding bottom cover to slow down the gas flow in the sample chamber. On the one hand, it prevents dust from contaminating the chamber during vacuuming, and on the other hand, it slows down the rapid loss of process gas during cleaning. At the same time, it can also prevent plasma bombardment of the surface of the workpiece to be cleaned from generating particulate contamination of the lower part of the sample chamber.

[0025] In this invention, a bias ring is nested around the outer periphery of the chuck. The bias ring is connected to an RF power supply, generating a self-bias voltage that attracts and accelerates plasma movement on the chuck surface. When a workpiece to be cleaned is present on the upper surface of the chuck, the plasma continuously bombards the surface of the workpiece, thus achieving the cleaning process. A shielding ring is fixed to the top surface of the bias ring to prevent direct plasma bombardment of the bias ring. Additionally, the shielding ring is connected to an exhaust hood to support the exhaust hood.

[0026] The chuck used for placement in this invention can not only be raised and lowered, but also rotated, enabling the workpiece to be cleaned to rotate while being cleaned, thereby increasing the uniformity of cleaning. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the sample chamber structure in this invention; Figure 3 This is a schematic diagram of the explosion of the sample chamber in this invention; Figure 4 This is a schematic diagram of the structure of the movable base in this invention. Figure 1 ; Figure 5 This is a schematic diagram of the structure of the movable base in this invention. Figure 2 ; Figure 6 This is a schematic diagram of the explosion of the gas equalization device in this invention; Figure 7 This is a schematic diagram of the inner shielding ring in this invention; Figure 8 This is a first state diagram of the gas equalization device in this invention; Figure 9 This is a second state diagram of the gas equalization device in this invention; Figure 10 This is a third state diagram of the gas equalization device in this invention; Figure 11 This is a schematic diagram of the assembly of the lifting mechanism and the shielding base in this invention. Figure 1 ; Figure 12 This is a schematic diagram of the assembly of the lifting mechanism and the shielding base in this invention. Figure 2 .

[0028] In the picture: 1-Sample chamber, 11-Transfer port, 12-Exhaust hood, 13-Shielding bottom cover, 14-Observation window; 2-Modible base, 21-Support flange, 22-Lifting mechanism, 221-Lifting motor, 222-Screw, 23-Rotating mechanism, 231-Rotating motor, 232-Connecting flange, 233-First telescopic bellows, 24-Vacuum electric feeder, 25-Elastic ejector pin, 26-Chuck, 27-Rotating shaft; 3-Gas equalization device, 31-Upper cover plate, 32-Air flow meter, 33-Air inlet pipe, 34-Lower gas equalization dish, 341-Top plate, 342-Gas equalization hole, 35-Outer shielding ring, 351-Outer ring body, 352-Inner protrusion, 36-Inner shielding ring, 361-Inner ring body, 362-Outer protrusion; 41-Plasma generation cavity; 42-Matching device; 43-Lifting mechanism; 5-Vacuum pumping device; 6-Lifting mechanism, 61-Lifting column, 62-Second telescopic bellows, 63-Push-pull mechanism; 7-Bias ring, 71-RF feedthrough, 72-RF matching circuit; 8-Shielding ring. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1: See Figure 1 and Figure 6-10 This embodiment provides a plasma cleaning chamber, comprising a sample chamber 1, a plasma generating chamber 41, and an air inlet chamber connected in sequence. The plasma generating chamber 41 is a component of a plasma generating device, which also includes a coil wound around the outer periphery of the plasma generating chamber 41. The coil is a solenoid coil and is connected in sequence to a matching device 42 and a radio frequency power supply. The air inlet chamber and the plasma generating chamber 41, as well as the sample chamber 1 and the plasma generating chamber 41, are sealed connections.

[0031] The plasma generating cavity 41 is a hollow ring structure made of non-metallic material to prevent the generation of an induced electromagnetic field in the plasma generating cavity 41 after the coil is fed with radio frequency current, thus avoiding energy waste. Simultaneously, the outer wall of the plasma generating cavity 41 is concave near the coil, ensuring overall strength while fixing the coil in the center of the plasma generating cavity 41. This facilitates the transfer of radio frequency energy from the coil to the plasma generating cavity 41, thereby making it easier to excite the plasma. The coil is an oxygen-free copper metal tube, hollow inside with water flowing through it to dissipate the heat generated by the coil itself after the radio frequency current is fed in. Furthermore, the coil surface can be coated with metallic silver to increase conductivity and reduce energy loss during radio frequency feeding.

[0032] A gas equalization device 3 is provided between the air inlet chamber and the plasma generating chamber 41. The gas equalization device 3 includes a lower gas equalization dish 34, an outer shielding ring 35, and an inner shielding ring 36 arranged coaxially from bottom to top. Multiple gas equalization areas are radially opened on the top plate 341 of the lower gas equalization dish 34. The opening or closing of each gas equalization area is adjusted by adjusting the position of the process gas entering the plasma generating chamber 41 and the zoned flow rate.

[0033] The process gas from outside diffuses evenly into the inlet chamber and then enters the plasma generation chamber 41 evenly through the gas equalization device 3 to generate plasma, which is then used to clean the surface of the workpiece to be cleaned. The gas equalization device 3 can adjust the position and flow rate of the process gas entering the plasma generation chamber 41, such as introducing process gas only into the central area of ​​the plasma generation chamber 41 or introducing process gas into the entire area of ​​the plasma generation chamber 41, thereby adapting to the cleaning of workpieces of different sizes and improving the utilization efficiency of the plasma.

[0034] Specifically, the air intake chamber includes an upper cover plate 31 fixed to the plasma generating chamber 41 with an opening. The upper cover plate 31 has a process gas port, which is connected to the process gas through an air intake pipe 33 and a gas flow meter 32. That is, an air intake chamber is formed between the upper cover plate 31 and the gas equalization device 3. After the flow rate of the process gas is controlled by the gas flow meter 32, it enters the air intake chamber through the air intake pipe 33 for diffusion.

[0035] like Figure 6 , 7 As shown, the outer wall of the lower gas equalizing dish 34 is fixed on the inner wall of the plasma generating chamber 41, and the outer shielding ring 35 and the inner shielding ring 36 are rotatably disposed on the top surface of the lower gas equalizing dish 34.

[0036] Specifically, the lower gas equalization dish 34 has a cylindrical structure, with a top plate 341 fixed at its top opening. The top plate 341 is provided with gas equalization holes 342. The gas equalization holes 342 located at the center of the top plate 341 form a central gas equalization area, and the gas equalization holes 342 located around the central gas equalization area and distributed in a spaced-out fan-shaped pattern form an outer gas equalization area. As shown in the figure, the central gas equalization area is a circular structure, and the outer gas equalization area is a spaced-out fan-shaped structure. In this embodiment, the diameter of the central gas equalization area is 150 mm, and the diameter of the outer gas equalization area is 150-350 mm. The specific dimensions can be designed according to the actual device, the workpiece to be cleaned, etc.

[0037] like Figure 7 As shown, the outer shielding ring 35 includes an outer ring body 351, and inner protrusions 352 are provided at equal intervals along the circumference inside the outer ring body 351; there is a gap between adjacent inner protrusions 352, and the gap and the inner protrusions 352 are fan-shaped structures of equal size.

[0038] The inner shielding ring 36 includes an inner ring body 361, and the outer ring body 361 is provided with outer protrusions 362 at equal intervals along the circumference; there is a groove between adjacent outer protrusions 362, and the groove and the outer protrusions 362 are fan-shaped structures of equal size.

[0039] When the inner shielding ring 36 is coaxially fitted at the center of the outer shielding ring 35, and the outer protrusion 362 is aligned with the inner protrusion 352 or located in the gap between two adjacent inner protrusions 352, the outer uniform air area is fully shielded, unshielded, or partially shielded to form three uniform air states.

[0040] In a specific embodiment, the lower gas equalization dish 34 is an inverted bowl-shaped structure made of insulating and sputter-resistant material, and is entirely embedded inside the plasma generation cavity 41 to prevent plasma from bombarding the intake cavity. The outer shielding ring 35 is a hollow ring structure, with the inner diameter of the inner protrusions 352 being approximately 250 mm. The area with a diameter of 250-350 mm is composed of spaced inner protrusions 352 and gaps. The inner shielding ring 36 is turbine-like, with a hollowed-out central area of ​​150 mm in diameter, and the outer periphery is arranged with fan-shaped outer protrusions 362 at intervals to form a shielding area with a diameter of 250 mm.

[0041] That is, the inner diameter of the inner ring 361 is the same as the diameter of the central gas uniform region, and the inner diameter of the outer ring 351 is the same as the diameter of the outer gas uniform region.

[0042] After the outer shielding ring 35 and the inner shielding ring 36 are coaxially fitted together, they are rotatably placed on the top plate 341 of the lower gas equalization dish 34. These three can be connected by a central shaft, allowing the outer shielding ring 35 and the inner shielding ring 36 to rotate around the central shaft. In addition, for automatic control, a servo motor can be used to drive the outer shielding ring 35 and the inner shielding ring 36 to rotate at a certain angle.

[0043] When the inner protrusion 352 of the outer shielding ring 35 is located in the outer ring of the fan-shaped structure on the outer gas equalization area, i.e., outer ring position 1, and the outer protrusion 362 of the inner shielding ring 36 is aligned with the inner protrusion 352 and located in the inner ring position 1, both of them completely cover the gas equalization holes 342 in the outer gas equalization area of ​​the lower gas equalization dish 34, only exposing the gas equalization holes in the hollow area of ​​the inner shielding ring 36 (i.e., the central gas equalization area). This is gas equalization position 1 (e.g., Figure 8 (As shown).

[0044] When the outer shielding ring 35 remains stationary, while the inner shielding ring 36 continues to rotate at a certain angle, i.e., when the outer protrusion 362 is located in the gap between adjacent inner protrusions 352 (i.e., inner ring position 2), the inner ring portion of the outer gas equalization area on the lower gas equalization dish 34 is exposed, while the gas equalization holes in the outer ring portion are blocked by the inner protrusions 352 of the outer shielding ring 35. This is gas equalization position 2 (e.g., Figure 9 (As shown).

[0045] When the inner shielding ring 36 remains stationary, while the outer shielding ring 35 rotates at a certain angle, i.e., when the inner protrusion 352 aligns with the outer ring at position 2, all the gas equalization holes in the outer gas equalization area of ​​the lower gas equalization dish 34 are exposed, meaning all the gas equalization holes in the lower gas equalization dish 34 are open. This is the gas equalization position 3 (e.g., ...). Figure 10 (As shown).

[0046] In this embodiment, the gas equalization device adjusts the opening or closing of each gas equalization zone by adjusting the positions of the outer shielding ring 35 and the inner shielding ring 36, forming three gas equalization positions to adjust the position and flow rate of the process gas entering the plasma generating chamber 41. Specifically, after the process gas enters the inlet chamber, it undergoes free diffusion within the inlet chamber, completing the first stage of gas equalization. Then, it slowly and evenly enters the lower gas equalization dish 34 through the aforementioned different gas equalization positions, completing the second stage of gas equalization. Finally, the uniform process gas enters the plasma generating chamber through the three different gas equalization positions of the gas equalization device 3, resulting in different gas rarefaction positions within the plasma generating chamber and different distributions of excited plasma energy density. This allows it to be applied to workpieces of different sizes to be cleaned, avoiding energy waste.

[0047] From the above, it can be concluded that the gas equalization device 3 is as follows: Figure 8 When the gas distribution position 1 is shown, the process gas enters from the center of the plasma generation chamber 41, which can clean the small-sized workpieces to be cleaned on the chuck 26; the gas distribution device is as follows: Figure 9 At position 2, as shown, medium-sized workpieces can be cleaned; the air distribution device is as follows: Figure 10 When the air is evenly distributed at position 3 as shown, large-sized workpieces can be cleaned.

[0048] In one specific embodiment, the transfer component transports the 4-inch wafer to be cleaned from the transfer port 11 to directly above the chuck 26. After the movable base 2 drives the chuck 26 to rise and receive the wafer, the transfer component exits the sample chamber 1. The transfer port 11 is sealed by a valve and evacuated to a vacuum state by the vacuum pumping device 5. Depending on the wafer size, the outer shielding ring 35 or the inner shielding ring 26 is rotated or rotated by a servo motor (such as a vacuum-compatible direct drive servo motor (e.g., a DD motor) or a servo motor + high-precision reducer) to keep the outer shielding ring 35 and the inner shielding ring 26 in the gas equalization position 1. After the cleaning chamber is evacuated to a vacuum state, a certain flow rate of process gas is introduced under the control of the gas flow meter 32. After the process gas passes through the first and second gas equalization processes described above, it enters the plasma generation chamber. Since the gas equalization position of the second gas equalization stage is the gas equalization position 1 at this time, the process gas will accumulate within a central diameter range of 150 mm. Subsequently, the plasma generator excites the plasma in the central region to adapt to the cleaning of the 4-inch wafer.

[0049] Similarly, when the wafer size is 8 inches, the outer shielding ring 35 and the inner shielding ring 26 are moved to the gas equalization position 2. When the wafer size is 12 inches, the outer shielding ring 35 and the inner shielding ring 26 are moved to the corresponding gas equalization position 3. It should be noted that the 4, 8, and 12-inch wafer sizes described in this embodiment are common sizes, but the synchronously changing gas equalization process is not only applicable to these three sizes. The key is that the gas equalization position can be synchronously changed according to the size of the part to be cleaned to achieve the most suitable cleaning area.

[0050] Example 2: The difference is the same as in Example 1: See Figure 1-3 To protect the lower part of the sample chamber and improve plasma utilization, a chuck 26 for carrying the workpiece to be cleaned is provided inside the sample chamber 1. A shielding bottom cover 13 is movably installed inside the sample chamber located on the outer periphery of the chuck 26. The shielding bottom cover 13 moves up and down along the inner wall of the sample chamber. The shielding bottom cover 13 is used to prevent process gases from entering the lower space of the sample chamber 1 from the periphery of the chuck 26, thus avoiding waste.

[0051] Specifically, the cleaning chamber in this invention is divided into three spaces based on the flow direction and function of the process gas: an inlet and gas equalization space, located between the upper cover plate and the gas equalization device 3, where the external process gas diffuses after entering the space to achieve the first gas equalization purpose; a plasma generation space, located between the gas equalization device 3, the chuck 26, and the shielding bottom cover 13, where the process gas enters the space after further equalization and distribution by the gas equalization device 3 to generate plasma for cleaning the workpiece; and a transfer and evacuation space, located in the lower half of the sample chamber 1, i.e. below the chuck 26 and the shielding bottom cover 13, used for the entry and exit of the workpiece to be cleaned and for obtaining a vacuum in the chamber, and isolated from the plasma generation space above by the shielding bottom cover 13.

[0052] In this embodiment, the sample chamber 1 is made of metal, and a shielding cover 13 is provided at its bottom to prevent plasma from directly bombarding the inner wall of the sample chamber 1, thus avoiding sputter contamination of the lower part of the sample chamber 1. Simultaneously, the shielding cover 13 moves up and down along the inner wall of the sample chamber 1, meaning it has a lifting action. When rising, it clears a passage for the workpiece to be cleaned, facilitating the loading and unloading of the workpiece and improving process efficiency. When descending, it completely shields the lower part of the sample chamber 1, preventing sputter contamination and waste.

[0053] like Figure 2 , 3As shown, a chuck 26 is provided inside the sample chamber 1, and an exhaust hood 12 and a shielding bottom cover 13 are arranged sequentially around the outer periphery of the chuck 26. A transfer port 11 is provided on one side of the sample chamber 1 for the entry and exit of the workpiece to be cleaned; a valve is installed on the transfer port 11, which is preferably an electronic valve in this embodiment. The valve can be automatically controlled to open and close by a controller. The valve is not only used to seal the sample chamber 1, but also to connect to other process chambers, increasing the expandability of the device. The opening and closing of the valve can achieve the self-isolation of the sample chamber 1 and the communication with other chambers.

[0054] The bottom end of the shielding cover 13 is connected to a lifting mechanism 6 for driving the shielding cover 13 to move up and down; when the shielding cover 13 is lowered into place, its bottom surface is flush with the top surface of the chuck 26, completely covering the lower part of the transfer port 11 and the sample chamber 1 (e.g., Figure 11 As shown), the lower half of the sample chamber is tightly protected from plasma bombardment. When the shielding base 13 is raised to its position, its bottom surface is flush with the upper wall of the transfer port 11, clearing a transfer channel for the workpiece to be cleaned (as shown). Figure 12 As shown, the transfer component carrying the workpiece to be cleaned can be moved through the transfer port 11 to directly above the chuck 26. After the transfer component exits from the transfer port 11, the valve at the transfer port 11 closes, and the lifting mechanism 6 lowers the shielding cover 13 back to the closed position, re-shielding the lower half of the inner wall of the sample chamber 1 to facilitate subsequent cleaning processes. The transfer component is known in the art, and this application does not make any improvements to it, so it will not be described in detail here.

[0055] The shielding bottom cover 13 is an integral concave ceramic ring, located at the top of the lifting mechanism 6 and integrally embedded in the sample cavity 1. On the one hand, it prevents the plasma from directly bombarding the inner wall of the metal sample cavity 1 and causing contamination, and on the other hand, it prevents the generation of eddy currents in the radio frequency and the resulting loss of radio frequency energy.

[0056] The lifting mechanism 6 includes a lifting column 61 connected to the bottom end of the shielding cover 13. The lifting column 61 is connected to a push-pull mechanism 63. A second telescopic bellows 62 is sleeved on the lifting column 61. The top end of the second telescopic bellows 62 is fixed to the bottom end face of the sample chamber 1 for sealing.

[0057] In this embodiment, the push-pull mechanism 63 can be a pneumatic cylinder or a hydraulic cylinder to provide push-pull power. Its piston rod is fixedly connected to the lifting column 61. The second telescopic bellows 62 is used to maintain vacuum isolation during the lifting movement. The top end of the lifting column 61 is threadedly connected to the shielding cover 13 to support the shielding cover 13 and transmit force.

[0058] In another embodiment, the inner wall of the sample chamber 1 is fixed with an n-shaped groove for engaging the top of the shielding cover 13. When the shielding cover 13 is raised to its position, its top is inserted into the n-shaped groove for docking, reducing vacuum leakage in the sample chamber. To allow the shielding cover 13 to move smoothly up and down, the n-shaped groove does not constrain or restrict the top of the shielding cover 13, meaning the shielding cover 13 can move smoothly up and down.

[0059] like Figure 3 As shown, an exhaust hood 12 is arranged in a ring between the chuck 26 and the shielding base 13, and the exhaust hood 12 has exhaust holes evenly distributed on it. The exhaust hood 12 has a flat annular structure, which is designed to slow down the gas flow in the sample chamber 1, on the one hand to prevent dust from contaminating the chamber during vacuuming, and on the other hand to slow down the rapid loss of process gas during cleaning. The exhaust hood 12 is placed inside the sample chamber and can be mounted on the chuck 26, the bias ring 7, or the shielding ring 8.

[0060] The exhaust hood 12 is made of a sputter-resistant material to prevent plasma bombardment from generating particles that contaminate the lower part of the sample chamber 1. Furthermore, the exhaust hood 12 can be made entirely of a sputter-resistant material, such as aluminum oxide, or it can be made of stainless steel coated with a sputter-resistant yttrium oxide coating.

[0061] Example 3: The difference is the same as in Embodiment 1 or Embodiment 2, except that: like Figure 1 The sample chamber 1 is provided with a chuck 26 for carrying the workpiece to be cleaned, and a bias ring 7 is nested in the lower groove on the outer periphery of the chuck 26.

[0062] Specifically, the bias ring 7 is connected to the RF power supply via the RF feedthrough 71 and the RF matching unit 72, causing the bias ring to generate a self-bias voltage that attracts and accelerates the plasma movement on its surface. Since the bias ring 7 engages with the lower outer circumference groove of the chuck 26, it is essentially embedded inside the chuck 26. The plasma, attracted by the bias voltage, moves towards the upper surface of the chuck 26. When a workpiece to be cleaned is present on the upper surface of the chuck, the plasma continuously bombards the surface of the workpiece, thus achieving the cleaning process.

[0063] To protect the bias ring 7, a shielding ring 8 is fixed on the top surface of the bias ring 7. The shielding ring 8 is made of non-metallic and sputter-resistant material and is placed above the bias ring 7 to prevent plasma from directly bombarding the bias ring 7. Its outer ring part is connected to the exhaust shroud 12 to support the exhaust shroud 12.

[0064] When the chuck 26 rotates, it rotates together with the bias ring 7 and the shielding ring 8, while the exhaust cover 12 may remain stationary or rotate together with the chuck.

[0065] Example 4: The difference is the same as in Example 1: To improve the uniformity of cleaning, a movable base 2 is provided at the bottom of the sample chamber 1. The movable base 2 includes a chuck 26 located inside the sample chamber 1 for supporting the workpiece to be cleaned, and a drive mechanism for driving the chuck 26 to move up and down or rotate within the sample chamber 1. That is, the chuck 26 can not only be raised and lowered to pick up and place the workpiece to be cleaned, but can also rotate. During operation, external process gas enters the air inlet chamber and then passes through the gas equalization device 3 to uniformly enter the plasma generation chamber 41 to generate plasma. This plasma cleans and rotates the surface of the workpiece placed on the chuck 26, resulting in a more uniform and thorough cleaning.

[0066] Specifically, such as Figure 1 , 4 As shown in Figure 5, the driving mechanism in this application includes a rotating shaft 27 connected to the chuck 26. The ends of the rotating shaft 27 are respectively connected to a lifting mechanism 22 and a rotating mechanism 23. The rotating shaft 27 is used to drive the chuck 26 to move up and down or rotate in the sample chamber 1. A support flange 21 is movably sleeved on the rotating shaft 27. The support flange is fixed to the bottom end face of the sample chamber 1 for sealing.

[0067] That is, the chuck 26 can be lifted and lowered axially and rotated around the axis. After the workpiece to be cleaned is transported to the top of the chuck 26 by the conveying device, the chuck 26 rises to the sampling position to receive the workpiece to be cleaned (e.g., Figure 4 (As shown). After the conveyor device leaves, the chuck 26 descends back to the working position (as shown). Figure 5 (As shown). After the chuck 26 is lowered to the working position, it rotates around the axis after plasma excitation, receiving plasma bombardment while rotating, thus completing the cleaning process. The rotation of the chuck 26 around the axis compensates for the parallelism deviation of the movable base caused by processing and installation, thereby increasing the uniformity of cleaning.

[0068] Specifically, the support flange 21 is fixed to the bottom end face of the sample chamber 1, and the support flange 21 connects the lifting mechanism 22 and the rotating mechanism 23. The rotating mechanism 23 includes a rotary motor 231, the output shaft of which is connected to a rotating shaft 27 via a magnetohydrodynamic shaft. The magnetohydrodynamic shaft and the rotating shaft 27 are then sealed and fastened inside the first telescopic bellows 233. The first telescopic bellows 233 is a hollow tube, one end of which is fixed to the support flange 21 via a connecting flange 232, and the other end is coaxially connected to the housing of the rotary motor 231 via the connecting flange 232. One end of the rotating shaft 27 is connected to the magnetohydrodynamic shaft, and the other end passes through the support flange 21 and is connected to the chuck 26 located in the sample chamber 1. The rotation of the rotary motor 231 drives the rotating shaft 27 and the chuck 26 fixed on the rotating shaft 27 to rotate together, thereby realizing the rotation of the chuck.

[0069] The lifting mechanism 22 includes a lead screw nut connected to the output shaft of the lifting motor 221. The lead screw nut is connected to the housing of the magnetohydrodynamic shaft located at the lower end of the first telescopic bellows 233 via the lead screw 222. When the lifting motor 221 rotates, it drives the lead screw 222 to rise (or fall), thereby driving the rotary motor 231 and the rotating shaft 27 to rise (or fall) together. At the same time, it drives the first telescopic bellows 233 to compress (or stretch), thereby completing the lifting action of the chuck 26.

[0070] An elastic pin 25 abuts against the outer wall of the rotating shaft 27. Due to its elasticity, the elastic pin 25 is always in close contact with the outer wall of the rotating shaft 27. The elastic pin 25 is connected to the ESC power supply through the vacuum power supply 24, and feeds the current through the rotating shaft 27 to the movable chuck 26, so that the surface of the chuck 26 generates static electricity to adsorb the workpiece to be cleaned.

[0071] Example 5: The difference between Examples 1 to 4 is as follows: A vacuum pumping device 5 is installed on the sample chamber 1; the vacuum pumping device 5 is the same as the prior art, and the present invention does not involve any improvement thereto. The vacuum pumping device 5 includes a fine pump and a main pump, wherein both the fine pump and the main pump are connected to the sample chamber 1 through valves. The fine pump and the main pump can quickly evacuate the cleaning chamber and provide a high vacuum environment.

[0072] A lifting mechanism 43 is installed on the outer wall of the sample chamber 1. The lifting mechanism 43 is connected to the plasma generating chamber 41 and is used to raise and lower the plasma generating chamber 41. That is, when the lifting mechanism 43 rises, it can lift the plasma generating chamber 41 upward, so that the plasma generating chamber 41 is separated from the sample chamber 1, which facilitates the installation or debugging of the components inside the sample chamber 1.

[0073] An observation window 14 is provided on the right side of the sample chamber 1, through which the internal condition of the sample chamber 1 can be observed. Furthermore, to provide more viewing angles, similar observation windows 14 can be added to both sides of the sample chamber 1.

[0074] Example 6: As another technical solution, the present invention also provides a plasma processing apparatus, which includes a compatible plasma cleaning chamber provided in the above embodiments.

[0075] The plasma processing equipment provided in this embodiment, by employing the plasma cleaning chamber provided in the above embodiments of the present invention as a pre-cleaning mechanism for the processed parts, can not only be applicable to the cleaning of processed parts of different sizes, but also improves the uniformity of process gas entry and its utilization rate, thereby reducing operating costs. It also improves cleaning uniformity and cleaning efficiency.

[0076] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of protection of the claims.

Claims

1. A compatible plasma cleaning cavity, comprising a cavity body sequentially connected by a sample cavity (1), a plasma generating cavity (41), and a gas inlet cavity, characterized in that: The uniform gas device (3) is provided between the gas inlet cavity and the plasma generating cavity (41), and comprises a lower uniform gas dish (34), an outer shield ring (35) and an inner shield ring (36) which are coaxially arranged in sequence from bottom to top.

2. The compatible plasma cleaning chamber of claim 1, wherein: The outer wall of the lower uniform gas dish (34) is fixed to the inner wall of the plasma generating cavity (41), and the outer shield ring (35) and the inner shield ring (36) are rotationally arranged at the top end surface of the lower uniform gas dish (34).

3. The compatible plasma cleaning chamber of claim 1, wherein: The lower uniform gas dish (34) is in a cylindrical structure, and a top plate (341) is fixed at the top opening of the lower uniform gas dish (34); the top plate (341) is provided with uniform gas holes (342), and the uniform gas hole (342) at the center of the top plate (341) forms a central uniform gas area, and the uniform gas holes (342) which are distributed in the form of interval sectors at the outer periphery of the central uniform gas area form peripheral uniform gas areas.

4. The compatible plasma cleaning chamber of claim 3, wherein: The outer shield ring (35) comprises an outer ring body (351), and inner protrusions (352) are equidistantly arranged on the inner side of the outer ring body (351) in the circumferential direction; The inner shield ring (36) comprises an inner ring body (361), and outer protrusions (362) are equidistantly arranged on the outer side of the inner ring body (361) in the circumferential direction; The inner shield ring (36) is coaxially embedded at the center of the outer shield ring (35), and when the outer protrusions (362) are aligned with the inner protrusions (352) or located at the gap positions between two adjacent inner protrusions (352), the peripheral uniform gas areas are fully shielded, not shielded or half shielded to form three uniform gas states.

5. The compatible plasma cleaning chamber of claim 1, wherein: A chuck (26) for carrying the workpiece to be cleaned is arranged in the sample cavity (1), and a shielding bottom cover (13) is movably arranged in the sample cavity (1) at the outer periphery of the chuck (26), and the shielding bottom cover (13) is lifted along the inner wall of the sample cavity (1).

6. The compatible plasma cleaning chamber of claim 5, wherein: A transmission port (11) is formed on one side of the sample cavity (1) for the workpiece to be cleaned to enter and exit; A jacking mechanism (6) is connected to the bottom end of the shielding bottom cover (13) for driving the lifting movement of the shielding bottom cover (13); when the shielding bottom cover (13) is lowered in place, the bottom end surface of the shielding bottom cover (13) is flush with the top end surface of the chuck (26), and the transmission port (11) and the lower part of the sample cavity (1) are fully shielded; when the shielding bottom cover (13) is raised in place, the bottom end surface of the shielding bottom cover (13) is flush with the upper wall of the transmission port (11), and a transmission channel is left for the workpiece to be cleaned.

7. The compatible plasma cleaning chamber of claim 6, wherein: An n-shaped clamping groove is fixed to the inner wall of the sample cavity (1) for clamping the top end of the shielding bottom cover (13); when the shielding bottom cover (13) is raised in place, the top end of the shielding bottom cover (13) is embedded in the n-shaped clamping groove; And / or, The jacking mechanism (6) comprises a jacking column (61) connected with the bottom end of the shielding bottom cover (13), the jacking column (61) is connected with a push-pull mechanism (63), a second telescopic bellows (62) is sleeved on the jacking column (61), and the top end of the second telescopic bellows (62) is fixedly connected with the bottom end surface of the sample cavity (1) for sealing.

8. The compatible plasma cleaning chamber of claim 5, wherein: An exhaust hood (12) is annularly arranged between the chuck (26) and the shielding bottom cover (13), and the exhaust hood (12) is uniformly provided with exhaust holes.

9. The compatible plasma cleaning chamber of claim 1, wherein: The sample cavity (1) is provided with a chuck (26) for carrying the workpiece to be cleaned, and a biasing ring (7) is nested in the lower groove of the outer periphery of the chuck (26). And / or, The biasing ring (7) is connected with the radio frequency power source through a radio frequency feedthrough (71) and a radio frequency matcher (72) in sequence, so that the biasing ring generates self-bias to attract and accelerate the plasma to bombard the surface of the chuck (26).

10. The compatible plasma cleaning chamber of claim 9, wherein: The top end surface of the biasing ring (7) is fixedly provided with a shielding ring (8).

11. The compatible plasma cleaning chamber of claim 1, wherein: The gas inlet cavity comprises an upper cover plate (31) fixedly connected with an opening of the plasma generating cavity (41), the upper cover plate (31) is provided with a process gas port, and the process gas port is connected with the process gas through an air inlet pipe (33) and a gas flow meter (32) in sequence.

12. The compatible plasma cleaning chamber of claim 1, wherein: The bottom end of the sample cavity (1) is provided with a movable base (2), the movable base (2) comprises a chuck (26) located in the sample cavity (1) and used for carrying the workpiece to be cleaned, and a driving mechanism used for driving the chuck (26) to move up and down or rotate in the sample cavity (1).

13. The compatible plasma cleaning chamber of claim 12, wherein: The driving mechanism comprises a rotating shaft (27) connected with the chuck (26), the end of the rotating shaft (27) is respectively connected with a lifting mechanism (22) and a rotating mechanism (23), and the rotating shaft (27) is used for driving the chuck (26) to move up and down or rotate in the sample cavity (1); a supporting flange (21) is movably sleeved on the rotating shaft (27), and the supporting flange (21) is fixed to the bottom end surface of the sample cavity (1) for sealing. And / or, The outer side wall of the rotating shaft (27) is abutted with an elastic ejector pin (25), the elastic ejector pin (25) is connected with an ESC power source through a vacuum electric feedthrough (24), current is fed to the movable chuck (26) through the rotating shaft (27), and static electricity is generated on the surface of the chuck (26) for adsorbing the workpiece to be cleaned.

14. The compatible plasma cleaning chamber of claim 1, wherein: The sample cavity (1) is provided with a vacuumizing device (5); And / or, The outer wall of the sample cavity (1) is provided with a lifting mechanism (43), the lifting mechanism (43) is connected with the plasma generating cavity (41) and used for lifting the plasma generating cavity (41).

15. A plasma processing device comprising the compatible plasma cleaning cavity according to any one of claims 1-14.

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