Plasma confinement device and plasma processing apparatus thereof

Abstract

The application discloses a plasma confinement device and a plasma processing device thereof. The plasma confinement device is arranged between a cavity sidewall of a vacuum reaction cavity and a lower electrode assembly. The plasma confinement device comprises an upper confinement ring and a lower confinement ring below the upper confinement ring. The upper confinement ring comprises a plurality of first spacers surrounding the lower electrode assembly. The lower confinement ring comprises a plurality of second spacers surrounding the lower electrode assembly. Each of the first spacers and each of the second spacers are staggered. A gas passage is formed between the first spacers and the second spacers adjacent to the first spacers. The plasma confinement device has the advantages that the staggered combination of the upper confinement ring and the lower confinement ring can ensure sufficient confinement ability to the plasma, reduce the hindering effect on the gas flow, improve the reaction cavity conductance, and help to realize the synergistic optimal adjustment of process conditions.

Description

Technical Field

[0001] This invention relates to the field of semiconductor equipment, and more specifically to a plasma confinement device and a plasma processing device thereof. Background Technology

[0002] In the manufacturing process of semiconductor devices, processes such as plasma etching, physical vapor deposition, and chemical vapor deposition are commonly used to micro-machin the semiconductor components or wafer substrates. The micro-machining process may include plasma-assisted processes, which are typically performed in a vacuum reaction chamber. Among these, plasma etching is a key process for fabricating the wafer into the designed pattern.

[0003] The principle of plasma etching in a vacuum reaction chamber is to introduce process gas into the chamber and activate it using radio frequency energy. This ignites and sustains the plasma, creating a plasma environment for etching the wafer. Taking a CCP etching chamber as an example, the excited plasma moves under the influence of an electric field and diffuses outwards. However, plasma has strong corrosive power. If it diffuses into non-reactive areas (such as the areas where some components of the electrode assembly are located), it may cause corrosion or erosion of these components, resulting in particulate contamination or other metal contamination within the chamber, shortening the lifespan of the components and reducing the reusability of the chamber. If the plasma is not confined to a specific working area, charged particles will collide with unprotected areas, leading to impurities and contamination on the semiconductor wafer surface.

[0004] To address these issues, the industry typically employs a plasma confinement assembly to limit the plasma as much as possible within the reaction region between the upper and lower electrode assemblies, thus protecting components in the non-reaction areas. However, with further advancements in process technology, higher demands are placed on the vacuum levels of etching equipment, as well as on the plasma confinement capabilities of the plasma confinement assembly.

[0005] It is understood that the above statements only provide background information related to the present invention and do not necessarily constitute prior art. Summary of the Invention

[0006] Based on the aforementioned technical problems, the purpose of this invention is to provide a plasma confinement device and a plasma processing device thereof. The plasma confinement device, through the cooperation of the upper and lower confinement rings, can ensure sufficient confinement of the plasma while reducing the gas resistance effect on the airflow, thereby improving the pumping efficiency and helping to achieve the optimal adjustment of various process conditions, thus ensuring the processing effect of the wafer.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0008] A plasma confinement device for a plasma processing apparatus, the plasma processing apparatus including a vacuum reaction chamber, wherein a lower electrode assembly is disposed within the vacuum reaction chamber.

[0009] The plasma confinement device is disposed between the cavity sidewall of the vacuum reaction chamber and the lower electrode assembly. The plasma confinement device includes an upper confinement ring and a lower confinement ring located below the upper confinement ring. The upper confinement ring includes a plurality of first spacers surrounding the lower electrode assembly, and the lower confinement ring includes a plurality of second spacers surrounding the lower electrode assembly. The first spacers and the second spacers are arranged alternately, and a gas channel is formed between the first spacers and the adjacent second spacers.

[0010] Optionally, the upper constraint ring and the lower constraint ring can move relative to each other vertically.

[0011] Optionally, the upper constraint ring is fixedly installed, and the lower constraint ring is connected to the driving device so that it can move up and down.

[0012] Optionally, the lower constraint ring includes a connection point for connection with the drive device;

[0013] The upper constraint ring is fixedly connected to the lower electrode assembly or the vacuum reaction chamber.

[0014] Optionally, the lower constraint ring is fixedly installed, and the upper constraint ring is connected to the driving device so that it can move up and down.

[0015] Optionally, the upper constraint ring includes a connection point for connection with the drive device;

[0016] The lower constraint ring is fixedly connected to the lower electrode assembly or the vacuum reaction chamber.

[0017] Optionally, there is a potential difference between the upper constraint ring and the lower constraint ring.

[0018] Optionally, the potential of the upper constraint ring is greater than the potential of the lower constraint ring;

[0019] Alternatively, the potential of the lower constraint ring is greater than the potential of the upper constraint ring.

[0020] Optionally, the upper constraint ring is connected to a bias power supply;

[0021] The lower constraint ring is connected to a bias power supply.

[0022] Optionally, the absolute value of the potential difference between the upper constraint ring and the lower constraint ring ranges from 0kV to 100kV.

[0023] Optionally, the aspect ratio of the gas channel is in the range of 5 to 20.

[0024] Optionally, the height of the gas channel is in the range of 40% to 100% of the height of the first spacer and / or the second spacer.

[0025] Optionally, at least some of the gas channels have equal widths;

[0026] Alternatively, at least a portion of the width of the gas channels increases from the center of the lower electrode assembly toward the sidewall of the cavity;

[0027] The spacing between at least some of the adjacent first spacers is equal;

[0028] Alternatively, the spacing between at least some of the adjacent first spacers tends to increase from the center of the lower electrode assembly toward the cavity sidewall;

[0029] The spacing between at least some of the adjacent second spacers is equal;

[0030] Alternatively, the spacing between at least some of the adjacent second spacers tends to increase from the center of the lower electrode assembly toward the cavity sidewall.

[0031] Optionally, the width of the gas channel ranges from 0.5 mm to 5 mm.

[0032] Optionally, multiple first spacers are connected by a first connector, and multiple second spacers are connected by a second connector.

[0033] Optionally, the projection positions of the first connector and the second connector in the vertical direction correspond to each other;

[0034] The first connector is disposed on the top of each of the first spacers;

[0035] The second connector is disposed at the bottom of each of the second spacers.

[0036] Optionally, the material used to fabricate the first spacer includes at least one of a conductor material or a semiconductor material;

[0037] The material used to prepare the second spacer includes at least one of a conductor material or a semiconductor material.

[0038] Optionally, the surfaces of the first spacer and / or the second spacer are provided with a plasma-resistant film.

[0039] Optionally, the plasma-resistant coating may comprise at least one of a Teflon coating, a yttrium oxide coating, or an anodic oxide coating.

[0040] Optionally, a plasma processing apparatus includes:

[0041] A vacuum reaction chamber, wherein a lower electrode assembly is disposed within the vacuum reaction chamber;

[0042] The plasma confinement device, as described above, is located within the vacuum reaction chamber.

[0043] Compared with the prior art, the technical solution of the present invention has at least the following advantages:

[0044] The plasma confinement device and plasma processing device of the present invention help to alleviate / solve the obvious contradictions and limitations of existing plasma confinement devices in terms of improving the flow conductance of the reaction chamber and confining the plasma. The plasma confinement device, through the staggered arrangement of the upper and lower confinement rings, can ensure sufficient confinement of the plasma while reducing the obstruction to the airflow, thereby improving the flow conductance of the reaction chamber. This helps to achieve the optimal adjustment of various process conditions and thus ensure the processing effect of the wafer.

[0045] Furthermore, the upper and lower confinement rings of the plasma confinement device can move relative to each other vertically. By dynamically adjusting the positions of the upper and / or lower confinement rings, the flow conductance of the reaction chamber and the plasma confinement capability can be dynamically adjusted, providing a larger adjustment window for the use of the process.

[0046] Furthermore, there is a potential difference between the upper and lower confinement rings of the plasma confinement device, which creates an electric field in the gas channel formed between the first spacer of the upper confinement ring and the second spacer of the adjacent lower confinement ring. This electric field greatly increases the confinement capability of the plasma and also helps to improve the flow conductance of the reaction chamber. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of a plasma processing device according to the present invention;

[0048] Figure 2 This is a schematic diagram of a plasma confinement device of the present invention in an unassembled state.

[0049] Figure 3 This is a top view of a plasma confinement device according to the present invention;

[0050] Figure 4 This is a cross-sectional schematic diagram of a plasma confinement device according to the present invention;

[0051] Figure 5 for Figure 4 Enlarged view of point A in the middle;

[0052] Figure 6 for Figure 4 A partial schematic diagram of a plasma confinement device;

[0053] Figure 7 This is a cross-sectional schematic diagram of another plasma confinement device according to the present invention;

[0054] Figure 8 for Figure 7 A partial schematic diagram of the plasma confinement device. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0056] It should be noted that, in this document, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Unless otherwise specified, an element defined by the phrase "comprising..." or "including..." does not exclude the presence of additional elements in the process, method, article, or terminal device that includes said element.

[0057] It should be noted that the accompanying drawings are all in a very simplified form and use non-precise ratios, and are only used to facilitate and clearly illustrate the purpose of the embodiments of the present invention.

[0058] like Figure 1The diagram shows a schematic of a plasma processing apparatus according to the present invention. The apparatus includes a vacuum reaction chamber 100, which is surrounded by a reaction chamber body and a chamber end cap 101. The reaction chamber body is typically made of a metallic material and includes a side wall 102 and a bottom wall 103. A wafer transfer port (not shown) is provided on the side wall 102 for transferring wafers between the inside and outside of the vacuum reaction chamber 100. The vacuum reaction chamber 100 includes a lower electrode assembly 110 disposed at the bottom of the chamber. The lower electrode assembly 110 has a support surface on which the wafer to be processed is placed. The vacuum reaction chamber 100 also includes an upper electrode assembly 120 disposed opposite to the lower electrode assembly 110. The space between the upper electrode assembly 120 and the lower electrode assembly 110 is a processing area for processing the wafer surface. The upper electrode assembly 120 includes a mounting base 121 connected to the top of the cavity and a gas spray head 122 disposed at the bottom of the mounting base 121. Process gas from a gas delivery device 130 is introduced into the vacuum reaction chamber 100 via the gas spray head 122 of the upper electrode assembly 120. Optionally, the upper electrode assembly 120 further includes an isolation ring 123, which surrounds the gas spray head 122 and extends downward. The isolation ring 123 is a moving ring that can move up and down, which can isolate the plasma in a designated area.

[0059] At least one radio frequency power supply 140 applies radio frequency energy to the lower electrode assembly 110 through a matching network, and dissociates the process gas into plasma P through capacitive coupling, so that the upper electrode assembly 120 and the lower electrode assembly 110 are in a plasma P environment for etching. The plasma P environment contains a large number of active particles such as electrons, ions, excited-state atoms, molecules and free radicals. These active particles can undergo various physical and / or chemical reactions with the surface of the wafer to be processed, thereby changing the morphology of the wafer to be processed and completing the processing of the wafer to be processed.

[0060] Furthermore, the vacuum reaction chamber 100 is provided with an exhaust port 104. Specifically, the exhaust port 104 is located on the bottom wall 103 of the chamber. A vacuum extraction device 150 exhausts the gas inside the vacuum reaction chamber 100, i.e., the reaction waste products, to the outside of the chamber through the exhaust port 104. Optionally, the vacuum extraction device 150 can be a molecular pump, a dry pump, or a vacuum pump assembly. Of course, the structure of the vacuum extraction device 150 is not limited to these, and it can also be any other device that can achieve the same function.

[0061] In practical applications, the vacuum extraction device 150 is typically located at the bottom of the vacuum reaction chamber 100, allowing the plasma P to more easily diffuse and escape in a vertically downward direction. Based on this, the plasma processing device also includes a plasma confinement ring 160, which is positioned between the chamber sidewall 102 and the lower electrode assembly 110 to confine the plasma P within the reaction region between the upper electrode assembly 120 and the lower electrode assembly 110. During operation, the reaction waste gas stream passes through the processing area, the plasma confinement ring 160, the cavity space below the plasma confinement ring 160, and the exhaust port 104 before being extracted and discharged outside the chamber. Some unreacted reactive particles in the reaction waste gas stream collide with and extinguish themselves upon passing through the plasma confinement ring 160, or come into contact with the plasma confinement ring 160, thus ensuring that the plasma P does not leak through the plasma confinement ring 160 into the non-reaction region, preventing damage to components in the non-reaction region.

[0062] As technology advances, the environmental pressure required for plasma P-etching is decreasing, especially in deep hole etching, where lower reaction chamber pressures are needed to expel reaction waste gas. With the same vacuum extraction device 150, reducing the air resistance of the gas flow channel can achieve a lower pressure environment. As a crucial component affecting air resistance in the gas flow channel, modifying the plasma confinement device 160 to obtain a larger gas flow channel size is the most effective way to improve conductivity. Currently, increasing the width of the gas flow channel or decreasing its height (length) is commonly used to improve the conductivity of the reaction chamber. However, when the size increases to a certain extent, the larger the gas flow channel, the easier it is for plasma P to leak through the gas flow channel into the non-reactive area below the plasma confinement device 160. The leaked plasma P in the non-reactive area will, on the one hand, contact the cavity sidewall 102 and the components in that area, causing corrosion of the cavity sidewall 102 and the components; on the other hand, the polymer generated by the reaction is more likely to accumulate on the cavity sidewall 102 and the components, and after a period of time, the deposited polymer will peel off, causing particulate contamination. Therefore, a contradiction arises between plasma P-confinement and increasing gas conductance, and resolving this contradiction is extremely important.

[0063] Based on the above, the plasma confinement device 160 of the present invention includes an upper confinement ring 161 and a lower confinement ring 162 located below the upper confinement ring 161 (see [link to previous document]). Figures 2 to 8The upper constraint ring 161 includes a plurality of first spacers 163 surrounding the lower electrode assembly 110, and the lower constraint ring 162 includes a plurality of second spacers 164 surrounding the lower electrode assembly 110. The first spacers 163 and the second spacers 164 are arranged alternately, and a gas channel 165 is formed between the first spacers 163 and the adjacent second spacers 164 (see [link to relevant documentation]). Figure 5 In actual use, the positions of the upper constraint ring 161 and the lower constraint ring 162 can be set according to actual needs.

[0064] Based on the above structure, the plasma confinement device 160 at least includes a gas channel 165 formed between the first spacer 163 and the adjacent second spacer 164, when the first spacer 163 and the second spacer 164 have non-overlapping areas in the lateral direction (see...). Figure 7 The plasma confinement device 160 further includes a first airflow channel 166 formed between adjacent first spacers 163 in a non-overlapping area and a second airflow channel 167 formed between adjacent second spacers 164 in a non-overlapping area. That is, the plasma confinement device 160 includes a first airflow channel 166, a second airflow channel 167, and a gas channel 165. The width of each channel may be different, resulting in differences in their airflow guiding ability and confinement ability for the plasma P. The width of the gas channel 165 is smaller than the width of the first airflow channel 166 and the second airflow channel 167. Typically, the depth-to-width ratio of the gas channel 165 is greater than that of the first airflow channel 166 and the second airflow channel 167, resulting in a stronger confinement ability for the plasma P. In practical use, plasma P first enters the first airflow channel 166, where some plasma P is annihilated. The remaining plasma P enters airflow channel 165 and is subsequently annihilated there, thus confining the plasma P. If some plasma P remains unannihilated, it will collide and extinguish upon entering the second airflow channel 167. During actual installation and use, the positions of the upper constraint ring 161 and the lower constraint ring 162 can be adjusted according to actual needs, along with the aspect ratios of each channel. This ensures the plasma confinement device 160's ability to confine plasma P while enhancing the airflow guidance effect to meet vacuum pumping requirements.

[0065] Furthermore, in this embodiment, the upper constraint ring 161 and the lower constraint ring 162 can move vertically relative to each other, meaning their relative positions can be dynamically adjusted. In any practical application, the lateral overlap between the first spacer 163 of the upper constraint ring 161 and the second spacer 164 of the lower constraint ring 162 can be adjusted, and the parameters of the first airflow channel 166, the second airflow channel 167, and the gas channel 165 will also change accordingly. The greater the lateral overlap between the first spacer 163 and the second spacer 164, the higher the height L of the gas channel 165 will be, and the higher its aspect ratio will be, thus enhancing its ability to confine the plasma P. This strengthens the overall confinement capability of the plasma confinement device 160 for the plasma P, effectively preventing plasma P from leaking below the plasma confinement device 160 and avoiding damage or contamination to components in the non-reactive area and the inner wall of the cavity. However, a high aspect ratio gas channel 165 may also increase the resistance to gas flow. The less the lateral overlap between the first spacer 163 and the second spacer 164, the higher the first airflow channel 166 and the second airflow channel 167, and the less obstruction the plasma confinement device 160 provides to the airflow. However, the confinement capability of the first airflow channel 166 and the second airflow channel 167 for the plasma P is slightly weaker than that of the gas channel 165. Therefore, the extent of the lateral overlap between the first spacer 163 and the second spacer 164 is crucial. When the relative position between the upper confinement ring 161 and the lower confinement ring 162 of the plasma confinement device 160 can be dynamically adjusted, the plasma confinement device 160 can adjust the lateral overlap between the first spacer 163 and the second spacer 164 in real time according to actual application requirements, changing the aspect ratio of each channel, so that the plasma confinement device 160 can increase its confinement capability for the plasma P while meeting the vacuum pumping requirements. Therefore, the plasma confinement device 160 can both confine the plasma P and reduce the flow resistance of the gas flow, improve the flow conductance of the reaction chamber, and achieve optimal adjustment of various process conditions, which helps to ensure the wafer processing effect. On the other hand, the plasma confinement device 160 also helps to increase the vacuum extraction device 150's ability to control the vacuum level in the vacuum reaction chamber 100.

[0066] In this embodiment, the upper constraint ring 161 is fixedly installed, and the lower constraint ring 162 is connected to the driving device (171, 172) so that it can move up and down (see...). Figure 1 Specifically, the upper constraint ring 161 is fixedly connected to a component of the lower electrode assembly 110, and the lower constraint ring 162 includes a connection point 1621 (see...). Figure 2The driving device is connected to the connection 1621 to drive the lower constraint ring 162. In actual use, the driving device controls the lower constraint ring 162 to move up and down, thereby changing the size parameters of the gas channel 165 formed between the first spacer 163 and the adjacent second spacer 164, and thus adjusting the confinement capability of the plasma confinement device 160 for the plasma P and its ability to guide the airflow.

[0067] like Figure 1 As shown, in this embodiment, the driving device includes a motor 171 and a drive rod 172. The motor 171 is connected to the lower constraint ring 162 at a connection point 1621 via the drive rod 172. The motor 171 and the drive rod 172 drive the lower constraint ring 162 to adjust up and down. Of course, the driving device can also be other structures capable of achieving the corresponding drive, such as a lead screw drive mechanism or a cylinder, etc., and this invention does not limit this. It is understood that the connection and fixing method of the upper constraint ring 161 is not limited to the above. In actual use, other connection and fixing methods can be adopted according to equipment conditions and space occupancy. For example, in another embodiment, the upper constraint ring 161 is fixedly connected to the vacuum reaction chamber 100. Furthermore, the relative up and down movement between the upper constraint ring 161 and the lower constraint ring 162 is not limited to the above method; it can also be achieved in other ways. For example, in yet another embodiment, the lower constraint ring 162 is fixedly installed, and the upper constraint ring 161 is connected to the driving device for up and down movement. Furthermore, in this embodiment, the upper constraint ring 161 includes a connection point for connection with the driving device; the lower constraint ring 162 is fixedly connected to the lower electrode assembly 110 or the vacuum reaction chamber 100. Alternatively, in another embodiment, the upper constraint ring 161 and the lower constraint ring 162 are respectively connected to the driving device, and both are movable to adjust the confinement capability and gas conduction capability of the plasma confinement device 160 for the plasma P. In practical applications, this can be configured according to actual needs and site conditions.

[0068] In practical applications, the height of the gas channel 165 can be used as a reference to adjust or set the upper constraint ring 161 and the lower constraint ring 162 to meet the corresponding application requirements. Optionally, the height range of the gas channel 165 is 40% to 100% of the height of the first spacer 163 and / or the second spacer 164. Similarly, the aspect ratio of the gas channel 165 can also be used as a reference to adjust or set the upper constraint ring 161 and the lower constraint ring 162. Optionally, the aspect ratio range of the gas channel 165 is 15 to 20. Of course, the height or aspect ratio of the gas channel 165 is not limited to the above ranges. In practical applications, other data ranges can be used, as long as the corresponding functional effect can be achieved. This invention does not impose any limitations on this.

[0069] Furthermore, to enhance the confinement capability of the plasma confinement device 160 for the plasma P, a potential difference exists between the upper confinement ring 161 and the lower confinement ring 162. A parallel-plate capacitor structure is formed between each pair of first spacers 163 and second spacers 164, and a directional electric field is generated in the gas channel 165. When charged particles pass through the gas channel, they are accelerated by the horizontal electric field force, colliding with the wall of the gas channel and accelerating their annihilation process, thereby restricting charged particles from passing through the plasma confinement device 160. Meanwhile, electrically neutral reaction products are not affected by the electric field force when passing through the plasma confinement device 160 and directly pass through the gas channel 165 of the plasma confinement device 160 and are extracted from the exhaust port 104. The electric field environment of the gas channel 165 further ensures the confinement capability of the plasma confinement device 160 for the plasma P. Simultaneously, due to the presence of the electric field environment, the requirements for the aspect ratio and other parameters of each channel in the plasma confinement device 160 can be relaxed. For example, if conditions permit, the width of each channel can be appropriately widened to reduce gas flow resistance, enhance the vacuuming efficiency of the gas extraction device, and thus improve the accuracy of the gas extraction device in controlling the gas pressure inside the cavity. On the other hand, a slightly lower first spacer 163 and a second spacer 164 can also be used to reduce the space occupied by the plasma confinement device 160, which helps to improve the space utilization rate inside the cavity.

[0070] It should be noted that the present invention does not limit the relative potential between the upper constraint ring 161 and the lower constraint ring 162, as long as a corresponding electric field environment can be formed at the gas channel 165. Optionally, the potential of the upper constraint ring 161 is greater than the potential of the lower constraint ring 162; or, the potential of the lower constraint ring 162 is greater than the potential of the upper constraint ring 161. In practical applications, the upper constraint ring 161 can be connected to one bias power supply, and the lower constraint ring 162 can be connected to another bias power supply to generate a potential difference between the upper constraint ring 161 and the lower constraint ring 162. Of course, the upper constraint ring 161 and the lower constraint ring 162 can also be connected to the same bias power supply, which controls the potentials of the upper constraint ring 161 and the lower constraint ring 162 respectively. Figure 5 and Figure 7 As shown, in this embodiment, the upper constraint ring 161 is connected to a DC high voltage potential, and the lower constraint ring 162 is grounded.

[0071] The magnitude of the potential difference between the upper constraint ring 161 and the lower constraint ring 162 affects the magnitude of the electric field force at the gas channel 165. Adjusting the current applied to the upper constraint ring 161 and / or the lower constraint ring 162 by the bias power supply can adjust the potential difference between them. Based on the principle of charged particle motion in an electric field, when the positions of the upper constraint ring 161 and the lower constraint ring 162 remain unchanged, the larger the potential difference between them, the stronger the force exerted by the electric field of the gas channel 165 on the charged particles. Optionally, the absolute value of the potential difference between the upper constraint ring 161 and the lower constraint ring 162 can range from 0 kV to 100 kV. It is understood that the absolute value of the potential difference between the upper constraint ring 161 and the lower constraint ring 162 is not limited to the above range; in other embodiments, it can be other ranges, as long as the corresponding function is achieved. This invention does not impose any limitations on this. On the other hand, the electric field of the gas channel 165 can be adjusted by moving the upper constraint ring 161 and the lower constraint ring 162 up and down relative to each other, thereby changing the plate area of ​​the parallel plate capacitor structure formed at the gas channel 165. In practical applications, this can be adjusted according to requirements and conditions.

[0072] On the other hand, in this invention, parameters such as the spacing between adjacent first spacers 163 and the spacing between adjacent second spacers 164 are not limited, nor is the width of the gas channel 165 limited. Optionally, the spacing between at least some adjacent first spacers 163 is equal; the spacing between at least some adjacent second spacers 164 is equal; and the width of at least some of the gas channels 165 is equal. For example, in this embodiment, the distance between all adjacent first spacers 163 of the upper constraint ring 161 is equal, the distance between all adjacent second spacers 164 of the lower constraint ring 162 is equal, and the width of each gas channel 165 is equal. That is, an equally spaced gas flow channel is formed between the upper constraint ring 161 and the lower constraint ring 162, which helps the gas extraction device to evenly regulate the gas pressure in the cavity, thereby improving its regulation accuracy. Optionally, the width of the gas channel 165 is in the range of 0.5mm to 5mm. Of course, the width of the gas channel 165 can also be other values. This invention does not limit this and can be set according to actual needs.

[0073] In practical applications, the spacing between adjacent first spacers 163 or second spacers 164 and the width of each gas channel 165 can also be different. In actual process environments, most of the process gas entering the vacuum reaction chamber 100 via the gas spray head 122 diffuses and distributes in the area above the wafer. Correspondingly, after the process gas is activated into plasma P, most of the plasma P is located in the reaction area between the upper electrode assembly 120 and the lower electrode assembly 110. Some plasma P diffuses from the reaction area toward the cavity sidewall 102. The closer to the cavity sidewall 102, the lower the concentration of plasma P gradually decreases, and the less constrained the plasma P is required. Optionally, at least some of the spacing between adjacent first spacers 163 tends to increase from the center of the lower electrode assembly 110 toward the cavity sidewall 102; at least some of the spacing between adjacent second spacers 164 tends to increase from the center of the lower electrode assembly 110 toward the cavity sidewall 102; and at least some of the widths of the gas channels 165 tend to increase from the center of the lower electrode assembly 110 toward the cavity sidewall 102. That is, the widths of the first airflow channel 166, the second airflow channel 167, and the gas channel 165 near the cavity sidewall 102 are greater than the widths of the first airflow channel 166, the second airflow channel 167, and the gas channel 165 near the lower electrode assembly 110. This confines the plasma P while increasing the airflow path, ensuring the vacuum extraction device 150's control over the vacuum level within the cavity. In practical applications, a suitable solution can be selected based on actual application requirements. For example, in one embodiment, the width of the gas channel 165 near the cavity sidewall 102 is twice the width of the gas channel 165 near the lower electrode assembly 110. This plasma confinement device 160 can still effectively limit the diffusion of plasma P and annihilate charged particles in plasma P. Under these conditions, it also greatly enhances the vacuum extraction device 150's control over the vacuum level within the vacuum reaction chamber 100.

[0074] like Figure 2 , Figure 5 and Figure 7 As shown ( Figure 5 and Figure 7 For along Figure 2 (A cross-sectional view cut along section line B) shows that the multiple first spacers 163 of the upper constraint ring 161 are connected by a first connector 168, and the multiple second spacers 164 of the lower constraint ring 162 are connected by a second connector 169. That is, the upper constraint ring 161 and the lower constraint ring 162 are each a single integral structure, facilitating their installation and use. Specifically, in this embodiment, the first connector 168 is disposed on the top of each of the first spacers 163 (…). Figure 2The upper constraint ring 161 has a protruding connecting surface at its top; the second connecting member 169 is disposed at the bottom of each of the second spacers 164. The second connecting member 169 is connected to the drive rod 172 of the driving device through a connecting point 1621. Through the action of the motor 171 and the drive rod 172, the second connecting member 169 is driven to move up and down, thereby realizing the up and down adjustment of the lower constraint ring 162. Further, as shown in the figure, in this embodiment, the projection positions of the first connecting member 168 and the second connecting member 169 in the vertical direction correspond, that is, the positions of the first connecting member 168 and the second connecting member 169 correspond to each other, so as to reduce the obstruction effect of the plasma confinement device 160 on the airflow and thus increase the cross-sectional area for gas flow.

[0075] Optionally, the material used to fabricate the first spacer 163 includes at least one conductive material or a semiconductor material; the material used to fabricate the second spacer 164 includes at least one conductive material or a semiconductor material, which can be set according to actual needs. For example, in this embodiment, a potential difference needs to be generated between the upper constraint ring 161 and the lower constraint ring 162. The first spacer 163, the first connector 168, the second spacer 164, and the second connector 169 are all made of conductive materials (such as aluminum) to achieve current conduction, thereby generating an electric field environment at the gas channel 165 that can affect charged particles.

[0076] To further protect the plasma confinement device 160, in this embodiment, the surfaces of both the first spacer 163 and the second spacer 164 are provided with a plasma-resistant P-corrosion film. Optionally, the plasma-resistant P-corrosion film comprises at least one of a Teflon film, a yttrium oxide film, or an anodic oxide layer. Of course, in practical applications, the plasma-resistant P-corrosion film may also contain other materials, and the present invention does not recommend limiting this, as long as it can protect the first spacer 163 and the second spacer 164 from corrosion. Furthermore, the plasma-resistant P-corrosion film is not limited to being disposed on the surfaces of the first spacer 163 and the second spacer 164. In other embodiments, the surfaces of the first connector 168 and / or the second connector 169 are also provided with a plasma-resistant P-corrosion film. That is, the present invention does not limit the placement of the plasma-resistant P-corrosion film and can be set according to actual needs.

[0077] It should be noted that the plasma confinement device 160 in this invention is not limited to the plasma processing device described above, but is also applicable to other types of plasma processing devices, such as inductively coupled plasma processing devices (ICP), etc., and this invention does not impose any limitations on them.

[0078] In summary, the plasma confinement device 160 and its plasma processing apparatus of the present invention include an alternating upper confinement ring 161 and a lower confinement ring 162. The first spacers 163 of the upper confinement ring 161 and the second spacers 164 of the lower confinement ring 162 are arranged alternately, forming a gas channel 165 between the first spacers 163 and their adjacent second spacers 164. Through the mutually cooperating upper and lower confinement rings 161 and 162, the plasma confinement device 160 allows the airflow to have various travel environments when passing through it. In practical applications, the positions of the upper and lower confinement rings 161 and 162 can be set according to requirements. While ensuring sufficient confinement of the plasma P, the plasma confinement device 160 can also reduce the obstruction to the airflow, thereby improving the flow conductance of the reaction chamber and facilitating the optimal adjustment of various process conditions, thus ensuring the wafer processing effect.

[0079] Furthermore, the upper confinement ring 161 and the lower confinement ring 162 of the plasma confinement device 160 can move up and down relative to each other. By dynamically adjusting the position of the upper confinement ring 161 and / or the lower confinement ring 162, the flow conductance and plasma P confinement capability of the plasma confinement device 160 can be dynamically adjusted. That is, the plasma confinement device 160 can both increase the flow conductance of the reaction chamber and confine the plasma P, providing a larger application window for the process.

[0080] Furthermore, there is a potential difference between the upper confinement ring 161 and the lower confinement ring 162 of the plasma confinement device 160, which creates an electric field in the gas channel 165 formed between the first spacer 163 of the upper confinement ring 161 and the second spacer 164 of the adjacent lower confinement ring 162. This electric field greatly increases the confinement capability of the plasma P and also helps to improve the flow conductance of the reaction chamber.

[0081] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A plasma confinement device for a plasma processing apparatus, the plasma processing apparatus comprising a vacuum reaction chamber, wherein a lower electrode assembly is disposed within the vacuum reaction chamber, characterized in that, The plasma confinement device is disposed between the cavity sidewall of the vacuum reaction chamber and the lower electrode assembly. The plasma confinement device includes an upper confinement ring and a lower confinement ring located below the upper confinement ring. The upper confinement ring includes a plurality of first spacers surrounding the lower electrode assembly, and the lower confinement ring includes a plurality of second spacers surrounding the lower electrode assembly. The first spacers and the second spacers are arranged alternately, and a gas channel is formed between the first spacers and the adjacent second spacers. The upper constraint ring and the lower constraint ring can move up and down relative to each other; the plasma confinement device may have a first airflow channel between adjacent first spacers, the gas channel between the first spacer and the second spacer, and a second airflow channel between adjacent second spacers.

2. The plasma confinement device as described in claim 1, characterized in that, The upper constraint ring is fixedly installed, and the lower constraint ring is connected to the driving device so that it can move up and down.

3. The plasma confinement device as described in claim 2, characterized in that, The lower constraint ring includes a connection point for connection to the drive device; The upper constraint ring is fixedly connected to the lower electrode assembly or the vacuum reaction chamber.

4. The plasma confinement device as described in claim 1, characterized in that, The lower constraint ring is fixedly installed, and the upper constraint ring is connected to the driving device so that it can move up and down.

5. The plasma confinement device as described in claim 4, characterized in that, The upper constraint ring includes a connection point for connection to the drive device; The lower constraint ring is fixedly connected to the lower electrode assembly or the vacuum reaction chamber.

6. The plasma confinement device as claimed in claim 1, characterized in that, There is a potential difference between the upper constraint ring and the lower constraint ring.

7. The plasma confinement device as described in claim 6, characterized in that, The potential of the upper constraint ring is greater than the potential of the lower constraint ring; Alternatively, the potential of the lower constraint ring is greater than the potential of the upper constraint ring.

8. The plasma confinement device as described in claim 6, characterized in that, The upper constraint ring is connected to a bias power supply; The lower constraint ring is connected to a bias power supply.

9. The plasma confinement device as described in claim 6, characterized in that, The absolute value of the potential difference between the upper constraint ring and the lower constraint ring ranges from 0 kV to 100 kV.

10. The plasma confinement device as claimed in claim 1, characterized in that, The aspect ratio of the gas channel ranges from 5 to 20.

11. The plasma confinement device as claimed in claim 1, characterized in that, The height range of the gas channel is 40% to 100% of the height of the first spacer and / or the second spacer.

12. The plasma confinement device as claimed in claim 1, characterized in that, At least some of the gas channels have equal widths; Alternatively, at least a portion of the width of the gas channels increases from the center of the lower electrode assembly toward the sidewall of the cavity; The spacing between at least some of the adjacent first spacers is equal; Alternatively, the spacing between at least some of the adjacent first spacers tends to increase from the center of the lower electrode assembly toward the cavity sidewall; The spacing between at least some of the adjacent second spacers is equal; Alternatively, the spacing between at least some of the adjacent second spacers tends to increase from the center of the lower electrode assembly toward the cavity sidewall.

13. The plasma confinement device as claimed in claim 1, characterized in that, The width of the gas channel ranges from 0.5mm to 5mm.

14. The plasma confinement device as claimed in claim 1, characterized in that, Multiple first spacers are connected by a first connector, and multiple second spacers are connected by a second connector.

15. The plasma confinement device as claimed in claim 14, characterized in that, The projection positions of the first connector and the second connector in the vertical direction correspond to each other; The first connector is disposed on the top of each of the first spacers; The second connector is disposed at the bottom of each of the second spacers.

16. The plasma confinement device as claimed in claim 1, characterized in that, The material used to fabricate the first spacer includes at least one of a conductor material or a semiconductor material; The material used to prepare the second spacer includes at least one of a conductor material or a semiconductor material.

17. The plasma confinement device as claimed in claim 1, characterized in that, The surface of the first spacer and / or the second spacer is provided with a plasma-resistant film.

18. The plasma confinement device as claimed in claim 17, characterized in that, The plasma-resistant corrosion-resistant film layer comprises at least one of a Teflon film layer, a yttrium oxide film layer, or an anodic oxide layer.

19. A plasma processing apparatus, characterized in that, Include: A vacuum reaction chamber, wherein a lower electrode assembly is disposed within the vacuum reaction chamber; The plasma confinement device as described in any one of claims 1 to 18 is located within the vacuum reaction chamber.

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