Semiconductor process chamber cleaning gas delivery structure

Abstract

The application belongs to the technical field of semiconductor equipment, and discloses a semiconductor process chamber cleaning gas conveying structure, which comprises a cleaning gas distribution cavity arranged in a lift pin mounting plate; a cleaning gas inlet pipeline for introducing cleaning gas into the cleaning gas distribution cavity; and a cleaning gas outlet arranged on the lift pin mounting plate and communicating with the cleaning gas distribution cavity. The application can directly supply cleaning gas to the lift pin mounting plate and diffuse to dead zones around the chamber bottom, the base support and the corrugated pipe which are difficult to clean by the existing top and bottom supply modes, thereby reducing the accumulation of residues in the lower area of the chamber and reducing the particle source.

Description

Technical Field

[0001] This application belongs to the field of semiconductor equipment technology, and more specifically, relates to a semiconductor process chamber cleaning gas delivery structure. Background Technology

[0002] In semiconductor manufacturing, process chambers are the main equipment for core processes such as etching and deposition. Due to the complex physical and chemical reactions that occur during the process, a large number of process byproducts and contaminants such as particles are generated in the chambers. These byproducts and particles continuously deposit on the inner walls and other surfaces of the process chambers. If these contaminants detach or adhere to the wafer surface with the airflow, they will impair the reliability of the semiconductor and affect the stability and consistency of product quality.

[0003] In PECVD equipment, process byproducts or polymer residues can accumulate not only between the spray head and the substrate during the process, but also around the substrate support, in the bellows, and at the bottom of the chamber. Particularly in SiO2, SiN, SiON, FSG, and TEOS series processes, deposits may form on the internal surface of the process chamber depending on the process conditions. To remove these deposits, remote plasma cleaning or in-situ cleaning is performed using NF3, O2, Ar, or mixtures thereof.

[0004] In conventional cleaning methods, free radical cleaning gas generated by a remote plasma source (RPS) is supplied from the top of the chamber or the direction of the spray head, then passes through the interior of the chamber and is discharged from the exhaust pipe. Although this structure can effectively clean the process area (i.e., the main reaction space between the spray head and the base), it has the problem that the cleaning gas cannot fully reach the invisible dead zones such as the bottom of the chamber, around the base support, and around the bellows.

[0005] In particular, the lower region of the chamber has lower conductivity, uneven gas residence time, and the cleaning free radicals supplied from above are consumed in the process area or on the chamber sidewalls before reaching this region, which may reduce cleaning efficiency. This leads to the continuous accumulation of residual film in the bottom region of the chamber, which may become a source of particulate matter, arc risk, abnormal pressure behavior, process drift, and shortened PM cycle time in the long run.

[0006] Traditional simple bottom cleaning gas injection structures can supply cleaning gas to the bottom of the chamber, but the supplied gas cannot stay and diffuse around the base support. Instead, it flows directly towards the exhaust port, which is not very effective for cleaning the area around the base support.

[0007] Therefore, in order to improve the cleaning effect of the process chamber, it is necessary to improve the existing cleaning airflow path. Summary of the Invention

[0008] [Technical Issues]

[0009] The purpose of this application is to solve the problem that in existing structures, the cleaning gas flows only in a specific direction within the chamber, failing to diffuse and linger around the base support, and instead flows directly to the exhaust port. This application addresses this issue by introducing cleaning gas into the lifting pin mounting plate and controlling the gas's supply location, diffusion space, injection direction, exhaust path, and residence time within the mounting plate. This allows for superior cleaning performance in areas surrounding the base support and in areas difficult for the cleaning gas to reach within the chamber.

[0010] [Technical Solution]

[0011] This application provides a cleaning gas delivery structure for a semiconductor process chamber. The process chamber includes a lifting pin mounting plate for driving a lifting pin to move up and down. The cleaning gas delivery structure includes: A cleaning gas distribution chamber is located inside the lifting pin mounting plate and is used to receive and distribute cleaning gas. A cleaning gas inlet pipe is used to introduce cleaning gas into the cleaning gas distribution chamber; A cleaning gas outlet is provided on the lifting pin mounting plate and communicates with the cleaning gas distribution chamber, for delivering the cleaning gas to the surrounding area of ​​the lifting pin mounting plate.

[0012] In one possible implementation, the cleaning gas distribution chamber is an annular space surrounding the base support.

[0013] In one possible implementation, multiple cleaning gas outlets are provided along the annular space.

[0014] In one possible implementation, the inner and / or outer sides of the lifting pin mounting plate are provided with cleaning gas outlets.

[0015] In one possible implementation, the upper end of the lifting pin mounting plate is provided with a cleaning gas outlet, which is offset from the position of the lifting pin.

[0016] In one possible implementation, the distribution of the cleaning gas is controlled by changing the size of the cleaning gas outlet according to its location.

[0017] In one possible implementation, the distribution of the cleaning gas is controlled by changing the number of cleaning gas outlets based on their location.

[0018] In one possible implementation, the distribution of the cleaning gas is controlled by changing the tilt angle and direction of the cleaning gas outlet according to its location.

[0019] In one possible implementation, each cleaning gas outlet is a porous structure.

[0020] In one possible implementation, the cleaning gas outlet is a continuous annular slot or slit; Alternatively, the cleaning gas outlet may be an intermittent annular slot or slit.

[0021] In one possible implementation, the cleaning gas outlet is used to form an air curtain of purge gas outside the cleaning process, the air curtain being used to prevent contaminants from clogging the cleaning gas outlet.

[0022] In one possible implementation, the upper end of the lifting pin mounting plate has an anti-overflow structure.

[0023] In one possible implementation, the anti-overflow structure is a barrier at the upper end of the lifting pin mounting plate used to change the straight flow direction of the gas flowing out of the cleaning gas outlet.

[0024] In one possible implementation, the anti-overflow structure is a guide wall at the upper end of the lifting pin mounting plate that guides the flow direction of the cleaning gas.

[0025] In one possible implementation, the anti-overflow structure refers to the cleaning gas outlet at the upper end of the lifting pin mounting plate being of a stepped form.

[0026] In one possible implementation, the anti-overflow structure refers to the cleaning gas outlet at the upper end of the lifting pin mounting plate being in the form of a labyrinth.

[0027] In one possible implementation, when the lifting pin mounting plate descends to the bottom of the process chamber, the cleaning gas inlet pipe is connected to the cleaning gas distribution chamber.

[0028] In one possible implementation, the lower end of the lifting pin mounting plate is open.

[0029] In one possible implementation, the lower end of the lifting pin mounting plate has an air inlet communicating with the cleaning gas distribution chamber, and the upper end of the cleaning gas inlet pipe is aligned and inserted into the air inlet of the lifting pin mounting plate.

[0030] In one possible implementation, the lower end of the lifting pin mounting plate has a cleaning gas outlet and an air inlet, the lifting pin mounting plate is lowered to have a gap with the bottom plate of the chamber, and the upper end of the cleaning gas inlet pipe is aligned and inserted into the air inlet of the lifting pin mounting plate.

[0031] [Beneficial Effects]

[0032] (1) This application can directly supply cleaning gas to the lifting pin mounting plate and diffuse it to the dead zone around the bottom of the chamber, the base support, and the bellows, which are difficult to clean with existing top and bottom supply methods, thereby reducing the accumulation of residue in the lower part of the chamber and reducing the particulate source.

[0033] (2) This application introduces cleaning gas into areas that are difficult to reach by conventional cleaning, such as the base support and the gap of the bellows, through the lifting pin mounting plate, thereby improving the overall cleaning uniformity of the chamber and alleviating the phenomenon of insufficient or excessive cleaning in specific areas.

[0034] (3) This application helps to extend the PM cycle in the chamber, improve particle stability, stabilize pretreatment recovery, improve chamber matching, optimize cleaning time and increase equipment uptime.

[0035] (4) The lower end of the lifting pin mounting plate of this application is open, which facilitates the connection between the cleaning gas inlet pipeline and the cleaning gas distribution chamber, thereby improving the gas transmission efficiency.

[0036] (5) The lower end of the lifting pin mounting plate of this application is open, and the cleaning gas input by the cleaning gas inlet pipe cleans the bottom plate of the chamber at the same time as entering the cleaning gas distribution chamber.

[0037] (6) Depending on the degree of pollution in the area, the cleaning gas outlet can be set with different sizes, quantities, tilt angles and directions to improve the cleaning effect of the corresponding area. Different sizes and quantities can meet the cleaning gas volume requirements of different polluted areas, and different tilt angles and directions can improve the directionality of the cleaning gas and improve the cleaning coverage of dead zones that are difficult to reach by existing cleaning gas flows, thereby enabling the gas to more comprehensively clean the contaminated components inside the chamber.

[0038] (7) The cleaning gas outlet of this application is in the form of a porous structure, which disperses the cleaning gas evenly and makes it easier for the cleaning gas to diffuse to the surrounding area for cleaning. In addition, the inclination angle of the porous structure can also be different, which can make the cleaning gas flow out in different directions.

[0039] (8) The cleaning gas outlet of this application adopts a slot or slit form, which can guide the gas to be sprayed out evenly over a longer linear range, thereby improving the cleaning effect.

[0040] (9) The cleaning gas outlet of this application can be used to form an air curtain of purging gas outside the cleaning process. The air curtain is used to block pollutants from clogging the cleaning gas outlet and extend the maintenance cycle of the gas conveying structure.

[0041] (10) This application forms an anti-overflow structure at the cleaning gas outlet at the upper end of the lifting pin mounting plate to prevent the cleaning gas from rising directly to the process area. Therefore, the cleaning gas is guided to the bottom of the chamber and the direction of the lining gap. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the process chamber structure; Figure 2 This is a schematic diagram of a standard lifting pin mounting plate; Figure 3 This is a schematic diagram of the semiconductor process chamber cleaning gas delivery structure according to Embodiment 1 of this application; Figure 4 This is a schematic diagram showing the dimensions of the cleaning gas outlet in Embodiment 1 of this application; Figure 5 This is a schematic diagram showing the tilt angle of the cleaning gas outlet in Embodiment 1 of this application; Figure 6 This is a schematic diagram of the cleaning gas outlet forming an air curtain in Embodiment 1 of this application; Figure 7 This is a schematic diagram of the barrier formed at the cleaning gas outlet in Embodiment 1 of this application; Figure 8 This is a schematic diagram of the semiconductor process chamber cleaning gas delivery structure according to Embodiment 2 of this application; Reference numerals: process chamber 1, base 3, spray head 2, corrugated pipe 4, lining 5, cleaning gas inlet pipe 100, lifting pin mounting plate 200, lifting pin 201, cleaning gas distribution chamber 300, cleaning gas outlet 400, air curtain 401, barrier part 402. Detailed Implementation

[0043] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0044] Please refer to Figure 1 , Figure 2 Inside the process chamber 1, the lower part is a base 3 for supporting the wafer, and the upper part has a spray head 2 for introducing process gas or cleaning gas as needed. The lifting mechanism is connected to the base support via a drive shaft, driving the base 3 to rise and fall. A bellows 4 is sealed on the outside of the drive shaft, with a gap between the bellows 4 and the drive shaft.

[0045] The lifting pin mounting plate 200 is located below the base of the process chamber, and multiple lifting pins are mounted on it. Driven by the drive mechanism (not shown) at the bottom of the chamber, the lifting pin mounting plate 200 acts as a power transmission carrier, driving all the lifting pins 201 fixed on it to perform synchronous vertical lifting movements.

[0046] The base 3 is equipped with lifting pin holes for the lifting pins to pass through. During the wafer loading and unloading process, the lifting pin mounting plate 200 works in conjunction with the lifting pins to achieve precise height switching. When the robot arm sends the wafer into the process chamber, the lifting pin rises to support the wafer; then the lifting pin mounting plate 200 descends to place the wafer smoothly on the electrostatic chuck; after the process is completed, the lifting pin mounting plate 200 rises again to separate the wafer from the chuck and lift it, providing sufficient clearance for the robot arm to remove it.

[0047] To improve the cleaning effect around the base support area Figure 1 The cleaning gas is introduced from both the top and bottom of the process chamber at the same time. However, even so, the cleaning gas still does not have an effective flow cleaning path in the area around the base support, nor does it have a space to stay and buffer, and it cannot effectively clean these gap areas.

[0048] Example 1

[0049] To effectively clean the lower part of the process chamber, this application provides a semiconductor process chamber cleaning gas delivery structure, including a cleaning gas inlet pipe 100 for introducing cleaning gas into a cleaning gas distribution chamber 300; the cleaning gas distribution chamber 300 for accommodating the cleaning gas inlet and distributing the gas to various cleaning gas outlets 400; and the cleaning gas outlets 400 for leading the cleaning gas out to the bottom area such as the periphery of the base support, thereby enhancing the cleaning effect on the bottom area.

[0050] In existing technologies, such as Figure 2 As shown, the lifting pin mounting plate 200 is typically a solid structure, used only for mounting the lifting pin. In this application, to provide space for gas retention around the base support, the lifting pin mounting plate 200 is hollow, with the hollow cavity serving as the cleaning gas distribution chamber 300. The lifting pin mounting plate 200 is annular, surrounding the base support. Therefore, the cleaning gas distribution chamber 300 can be an annular space surrounding the base support, distributing the cleaning gas to a 360° area around the base support, thereby improving the distribution range of the cleaning gas around the base support.

[0051] Furthermore, this application does not exclude the possibility that the lifting pin mounting plate 200 can also be other shapes. For example, the lifting pin mounting plate 200 can be two or more blocks, which are fixedly connected to each other by rods or the like. Since the blocks cannot form airflow channels to communicate with each other, the lifting pin mounting plate 200 with this structure can form multiple cleaning gas distribution chambers 300. Alternatively, a continuous airflow channel can be formed between the blocks by connecting pipes. In the following description, the cleaning gas delivery structure is illustrated only by taking the lifting pin mounting plate 200 as an example of being annular. For the cleaning gas delivery structure with multiple cleaning gas distribution chambers 300, the setting of the cleaning gas inlet pipe 100 and the cleaning gas outlet 400 is basically similar to that of the annular cleaning gas distribution chamber 300.

[0052] like Figure 3 The diagram shows a cross-sectional view of the process chamber. The lifting pin mounting plate 200 is annular around the base support and is located at the bottom of the process chamber. Inside the plate, there is an annular cleaning gas distribution chamber 300. A liner 5 is provided on the side wall of the process chamber 1. A cleaning gas inlet pipe 100 is provided on the bottom plate of the process chamber. The cleaning gas inlet pipe 100 passes through the bottom plate of the process chamber and connects upward to the cleaning gas distribution chamber 300, thereby introducing cleaning gas into the cleaning gas distribution chamber 300.

[0053] It should be noted that the lifting pin mounting plate 200 is adjustable in height, such as... Figure 3 As shown, the upper end of the cleaning gas inlet pipe 100 is plugged into the air inlet of the lifting pin mounting plate 200, so the upper end of the cleaning gas inlet pipe 100 must be aligned with the air inlet of the lifting pin mounting plate 200.

[0054] The cleaning gas distribution chamber 300 has a certain volume, which can temporarily buffer a certain amount of cleaning gas. This can reduce airflow fluctuations and distribute the cleaning gas in various directions. A cleaning gas outlet 400 can be provided on the side wall of the lifting pin mounting plate 200, communicating with the cleaning gas distribution chamber 300. The cleaning gas outlet 400 can be multiple air outlets arranged at annular intervals. Multiple cleaning gas outlets 400 can be provided on both the inner and / or outer sides of the lifting pin mounting plate 200. The inner cleaning gas outlet 400 can guide the cleaning gas to the area around the base support, the corrugated pipe gap area, etc., while the outer cleaning gas outlet 400 can guide the cleaning gas to the area of ​​the inner liner 5 and the bottom area of ​​the chamber, thus cleaning not only the area around the base support but also the adjacent areas of the inner liner 5 and the bottom area of ​​the chamber.

[0055] Traditionally, cleaning gases are typically introduced into the process chamber 1 from either the top or bottom, and then flow at a certain velocity towards the suction port under the suction of a vacuum pump, making it difficult for them to linger in the substrate support area. This application, through its cleaning gas delivery structure, prevents the cleaning gas from flowing directly towards the chamber exhaust port. Instead, the gas lingers and diffuses around the substrate support, thereby cleaning the area surrounding it. Therefore, this application can directly supply cleaning gas to the area around the substrate support that is difficult to clean using existing gas supply methods. This reduces the accumulation of residues in this area, reducing or eliminating conditions that could lead to the formation of microparticle contaminants on the wafer surface.

[0056] Furthermore, as the cleaning gas diffuses around the base support and disperses in all directions, it improves the cleaning balance around the base support and the inner wall of the chamber. This enhances the overall cleaning uniformity of the chamber and alleviates under- or over-cleaning in specific areas.

[0057] The cleaning gas can be NF3 radicals, O2 radicals, or a mixture of NF3 and O2 radicals activated by RPS (Remote Plasma Source), and can be supplied together with one or more gases such as Ar, N2, and He as needed. The cleaning gas can be independent of the existing cleaning gas pipeline at the top of the process chamber, or it can be branched off from the upper cleaning gas pipeline.

[0058] In one feasible embodiment, at least one row of cleaning gas outlets 400 can be arranged in a ring on the inner side of the lifting pin mounting plate 200, for example, two rows of cleaning gas outlets 400 can be arranged, and adjacent cleaning gas outlets 400 can be staggered to make the airflow distribution of cleaning gas on the inner side more uniform.

[0059] In one feasible embodiment, at least one row of cleaning gas outlets 400 can be arranged in a ring on the outer side of the lifting pin mounting plate 200, for example, two rows of cleaning gas outlets 400 can be arranged, and adjacent cleaning gas outlets 400 can be staggered to make the airflow distribution of cleaning gas on the outer side more uniform.

[0060] The cleaning gas outlet 400 can also be located at the top of the lifting pin mounting plate. Since the top of the lifting pin mounting plate is equipped with a lifting pin, the position of the cleaning gas outlet 400 should avoid the lifting pin. Leading the gas out from the cleaning gas outlet 400 can further expand the cleaning gas distribution range around the base support.

[0061] In one feasible embodiment, the distribution of cleaning gas can be controlled by changing the size of the cleaning gas outlet 400 according to its location. For example, the cleaning gas outlet 400 can be set to different sizes according to the degree of pollution in the area. Figure 4 In the middle, the area where the inner cleaning gas outlet 400 is located has greater particulate pollution, so its size is larger than that of the outer outlet, which can introduce more gas into the area for more thorough cleaning.

[0062] In one feasible embodiment, the distribution of cleaning gas can be controlled by varying the number of cleaning gas outlets 400 according to their location. For example, the number of cleaning gas outlets 400 can be adjusted based on the varying levels of contamination around the base support, thereby regulating the distribution ratio of the cleaning gas. In areas of the base support with more severe contamination, a denser network of cleaning gas outlets 400 can be provided on the inner side of the lifting pin mounting plate, while in areas with contaminated lining, a sparser network of cleaning gas outlets 400 can be provided on the outer side of the lifting pin mounting plate.

[0063] In one feasible embodiment, the distribution of cleaning gas can be controlled by changing the tilt angle and direction of the cleaning gas outlet 400 according to its location. For example, the cleaning gas outlet 400 can be formed at a certain tilt angle; for instance, it can be formed to tilt upwards toward the base support, or downwards toward the bottom region of the chamber, or it can be tilted in other directions. Figure 5 In the middle, the cleaning gas outlet 400 is tilted upward toward the lower surface of the base.

[0064] The tilt angle and tilt direction of each cleaning gas outlet 400 can be different, which can be determined according to the location of particulate contamination in the area faced by the cleaning gas outlet 400, so that the cleaning gas sprayed out can more easily reach the contamination location.

[0065] Furthermore, the cleaning gas outlet 400 not only introduces gas to clean the base support area, but also guides the cleaning gas to more areas. For example, the outer cleaning gas outlet 400 can guide the cleaning gas to the inner lining area, while the upper cleaning gas outlet 400 can guide the cleaning gas to the area around the base, allowing the cleaning gas to flow through more areas. By setting cleaning gas outlets 400 at different tilt angles, the cleaning gas can be directed at various angles, improving the directionality of the cleaning gas and expanding the cleaning coverage of dead zones that are difficult to reach with existing cleaning gas flows. This allows the gas to more comprehensively clean the contaminated components inside the chamber.

[0066] In one feasible embodiment, the cleaning gas outlet 400 can be designed with its shape, orientation, and angle as needed to adjust the discharge volume, direction, and angle of the cleaning gas. For example, the cleaning gas outlet 400 can be various shapes such as a circular hole, a square hole, a slot, or a slit, and can also be in various forms such as porous holes or air curtains.

[0067] For example, at least one cleaning gas outlet 400 can be in the form of a porous structure, through which the cleaning gas is evenly dispersed and flows out, making it easier for the cleaning gas to diffuse into the surrounding area for cleaning. The porous structure may have at least four holes. Furthermore, the inclination angle of the porous structure can be different, allowing the cleaning gas to flow out in different directions.

[0068] A slot or slit refers to the cleaning gas outlet 400 of the lifting pin mounting plate having a narrower, flatter opening compared to circular or square orifices. Unlike the point-like airflow ejected from a circular orifice, a slot or slit guides the gas to be ejected uniformly over a longer linear range. Continuous slots / slits can form a uniform, continuous airflow. More specifically, the slot or slit can be annular and connected to the entire cleaning gas distribution chamber 300, or it can be an intermittent annular slot or slit, thus forming an airflow outlet much longer than a circular or square orifice.

[0069] Both slots and slits can be one or more annular structures. Slots generally have a wider cross-sectional width than slits, resulting in a gentler airflow, while slits allow for a higher airflow velocity. The configuration can be tailored to different cleaning process requirements. Slots are suitable for cleaning large areas of a chamber, such as the lining area.

[0070] The slit flow field exhibits high velocity, which can guide the cleaning gas to a specific area, making gas backflow or diffusion less likely. The base support, drive shaft, bellows, and the lifting pin holes on the base all have some mechanical clearances. These areas are dead zones where process byproducts easily intrude and accumulate. The slits can generate high-velocity cleaning gas that is less prone to diffusion, making it easier to guide the gas into these narrow gaps for cleaning.

[0071] Furthermore, slots and slits are not limited to being horizontal annular shapes. They can also be formed by extending at an angle along the annular lifting pin mounting plate to create an inclined annular slot or slit, allowing for precise control of the airflow direction and angle. For example, by setting a downward-sloping slit, the cleaning gas can be forced to blow at a specific angle towards a specific area of ​​the chamber.

[0072] Furthermore, the slots and slits are not limited to being annular; they can be multiple curved or straight slots and slits designed as needed. For example, slots or slits can be set around the bellows gap area specifically for cleaning the bellows gap.

[0073] In one feasible embodiment, the cleaning gas outlet 400 can also be an air curtain type, which can be formed by adjusting the flow rate of the slit. Outside of cleaning processes, such as deposition and other processes, the air curtain can prevent particles from other areas from falling into that area. For example... Figure 6 As shown, an air curtain 401 is formed. In this embodiment, an inert gas (such as nitrogen or argon) is introduced into the cleaning gas outlet 400 to form an air curtain, which can prevent contaminants generated during the deposition process from entering the cleaning gas outlet 400 and accumulating and clogging the cleaning gas outlet 400, thereby extending the maintenance cycle of the cleaning gas outlet in the lifting pin mounting plate.

[0074] Figure 6 The example shown is just one air curtain. Multiple air curtains can be formed as needed to shield a certain area, preventing or reducing the likelihood of particles from being swept away by cleaning gas from other locations from falling into the shielded area. It should be noted that the gas used to form the air curtain can be a purging gas, which is different from the cleaning gas.

[0075] In one feasible embodiment, to prevent cleaning gas from directly flowing into the process area, thereby contaminating the process space or causing unnecessary gas disturbance, an anti-overflow structure can be formed on the lifting pin mounting plate to prevent the cleaning gas from rising directly into the process area. Therefore, the cleaning gas is guided to the base support and the bottom of the chamber, limiting its unnecessary flow into the process area. The anti-overflow structure can be one or more combinations of a barrier, a guide wall, a stepped structure, or a labyrinth path. Furthermore, an anti-overflow structure is provided at the cleaning gas outlet 400 at the upper end of the lifting pin mounting plate.

[0076] For example, the blocking part is a protruding baffle on the lifting pin mounting plate. The baffle directly cuts off the straight flow path of the gas. When the cleaning gas attempts to diffuse upward, the blocking part forces the gas to change direction or reduce the flow rate, effectively reducing the excessive diffusion of the cleaning gas into the process area.

[0077] like Figure 7 As shown, the lifting pin mounting plate has multiple cleaning gas outlets 400. If cleaning gas flows into the process area at the same time, the cleaning gas will flow excessively into the process area. By setting a blocking part 402 at some or all of the cleaning gas outlets 400 at the upper end, the airflow can be changed and the flow of this part of the cleaning gas into the process area can be reduced.

[0078] The blocking part 402 can be changed according to the shape of the cleaning gas outlet 400. For example, if the cleaning gas outlet 400 is a circular hole spaced apart on the lifting pin mounting plate, then the blocking part 402 is provided above the circular hole. If the cleaning gas outlet 400 is an annular slot or slit, then the blocking part 402 is an annular blocking part provided above the slot or slit.

[0079] The blocking part 402 can partially or completely block the cleaning gas outlet 400. If it partially blocks the outlet, it reduces the direct flow of cleaning gas into the process area. For example, the blocking part 402 can be inclined or have perforations. If it completely blocks the outlet, the gas from the blocked outlet 400 will not flow directly into the process area, but it will still flow through the process area as the gas diffuses, thus reducing the amount of cleaning gas flowing into the process area.

[0080] For example, the guide wall can be a guide surface with a certain angle, an arc-shaped concave surface, or a vertical, horizontal, or inclined guide surface that is installed on the side wall of the lifting pin mounting plate and communicates with the cleaning gas outlet 400. The guide wall guides the cleaning gas to flow along a specific path by changing the direction and trajectory of the cleaning airflow. For example, by setting the guide wall, some of the cleaning gas does not pass through the base support, thereby preventing the base support from being excessively cleaned.

[0081] For example, the stepped structure refers to the cleaning gas outlet 400 being configured as a stepped hole, so that the diameter of the cleaning gas outlet 400 gradually decreases, reducing the amount of cleaning gas flowing out and preventing excessive cleaning gas from flowing into the process area.

[0082] For example, the maze channel refers to the cleaning gas outlet 400 being set in a maze shape, which reduces the amount of cleaning gas flowing out of the cleaning gas outlet 400 at that location, thus preventing excessive cleaning gas from flowing into the process area.

[0083] In one feasible embodiment, although the lifting pin mounting plate is typically lowered to the bottom of the chamber during cleaning, this application does not preclude lowering the lifting pin mounting plate to a position with a gap between it and the chamber floor, allowing gas to flow through this gap. Figure 8 As shown, a cleaning gas outlet 400 can also be provided at the lower end of the lifting pin mounting plate. The cleaning gas outlet 400 at the lower end can also discharge cleaning gas to the lower part of the chamber to clean the contaminants that may accumulate between the lower end of the lifting pin mounting plate and the bottom plate of the chamber.

[0084] In other words, the upper, inner, outer, and lower ends of the lifting pin mounting plate 200 are all equipped with cleaning gas outlets 400, which can deliver cleaning gas to more areas at the bottom of the chamber, especially areas such as the corrugated pipe gap, base support, gap between the liner and the chamber bottom plate, and the area between the lower end of the lifting pin mounting plate and the chamber bottom plate, which are areas that are prone to contamination. These areas can be thoroughly cleaned by the cleaning gas flowing out from the lifting pin mounting plate, further improving the cleaning effect.

[0085] In one feasible embodiment, a separate suction pipe, independent of the process chamber suction pipe, can be installed below the cleaning gas distribution space formed by diffusion through the lifting pin mounting plate, for example, in the process chamber area below the lifting pin mounting plate. This allows the cleaning gas to be guided to diffuse and clean primarily within this distribution space, reducing the possibility of diffusion to excessively distant areas. Figure 1 The suction pipeline is located in the process chamber area below the lifting pin mounting plate. It should be noted that... Figure 1 Since it's a two-dimensional diagram, the suction tube and the corrugated tube area appear to overlap. In reality, the suction tube and the corrugated tube are at different depths perpendicular to the paper and do not interfere with each other.

[0086] Through Embodiment 1, this application can extend the PM cycle of a chamber. The PM status refers to the current preventative maintenance cycle stage, cleanliness level, and wear / aging degree of components. It reflects how long it has been since the last deep maintenance and the current accumulation of contaminants inside the chamber. As the equipment operates, the wear degree of components and the accumulation of contaminants inside the chamber are often uneven in the vertical direction. At different stages of the PM cycle, if the accumulated contamination in the lower part of the chamber is close to a critical value, or if the aging of lower components leads to a decrease in cleaning efficiency, cleaning gas can be delivered to that area via the lifting pin mounting plate for targeted deep cleaning, thereby extending the overall PM cycle.

[0087] This improves particle stability. The substrate support area is a high-risk zone for particle contamination, where byproducts generated during the process or particles detached from the chamber walls easily deposit. The cleaning gas introduced through the lifting pin mounting plate forms a cleaning airflow around the substrate support, promptly stripping away and removing deposits from these areas. This significantly reduces wafer surface defects caused by particles falling from below the substrate, improving product yield.

[0088] The pretreatment process allows for stable recovery. After each PM (partial process) cycle, the process chamber requires pretreatment to return to a stable state. Residual contaminants in the substrate support area can cause fluctuations in process parameters for the first few wafers. Cleaning gas introduced via the lifting pin mounting plate can pre-clean this area before pretreatment, accelerating chamber stabilization.

[0089] This improves chamber matching by configuring standardized, independent cleaning air paths in the base support area via a lifting pin mounting plate, ensuring consistent cleanliness and airflow distribution in this critical area. It also reduces process deviations between equipment and improves yield and consistency in parallel production across multiple machines.

[0090] This invention optimizes cleaning time. In conventional cleaning, whether the cleaning gas is introduced from the top or bottom, it gradually diffuses from the top or bottom of the chamber, failing to effectively diffuse to areas such as the base support. Cleaning relies on the natural diffusion of airflow to the area below the base, which is inefficient and time-consuming. This application, through an independent gas path, can directly and efficiently deliver the cleaning gas to the area surrounding the base, significantly shortening the overall cleaning time of the chamber.

[0091] This can improve equipment uptime. The accumulation of contaminants around the base support is one of the main reasons for equipment downtime. This application uses an independent air path directly to the lifting pin mounting plate for efficient cleaning, resulting in better cleaning effect and effectively slowing down the rate of contaminant accumulation, thus improving the overall efficiency of the equipment.

[0092] Example 2

[0093] The technical content of Embodiment 2 is basically the same as that of Embodiment 1, except that the lifting pin mounting plate 200 is open at the lower end. That is, the lower end of the cleaning gas distribution chamber 300 is not closed; it is directly machined onto the lower end surface of the lifting pin mounting plate 200. As the lifting pin descends, the lifting pin mounting plate 200 also descends to the bottom, and its cleaning gas distribution chamber 300 is integrated with the bottom plate of the process chamber. Cleaning gas entering from the cleaning gas inlet pipe 100 can enter the cleaning gas distribution chamber 300 and then be distributed to each cleaning gas outlet 400.

[0094] Because the lower end of the lifting pin mounting plate 200 is open, chamber cleaning can only be performed when the lifting pin mounting plate 200 is lowered to the bottom. Otherwise, a distribution chamber to contain the cleaning gas cannot be formed, and the cleaning gas cannot be reliably distributed to each cleaning gas outlet 400. This is consistent with the conventional process chamber cleaning procedure, where the lifting pin mounting plate needs to be lowered to the bottom for conventional cleaning.

[0095] Furthermore, since the lower end of the lifting pin mounting plate 200 is open, the cleaning gas inlet pipe 100 does not need to be aligned with the inlet, reducing the difficulty of adaptation. The cleaning gas inlet pipe 100 can be flush with the chamber floor plate or higher than the chamber floor plate. It is preferred to be flush with the chamber floor plate.

[0096] The other technical aspects of Embodiment 2 are the same as those of Embodiment 1, and will not be described in detail here.

[0097] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications are all within the protection scope of the claims of the present invention.

Claims

1. A semiconductor process chamber cleaning gas delivery structure, wherein the process chamber has a lifting pin mounting plate for driving the lifting pin to move up and down, characterized in that, The cleaning gas delivery structure includes: A cleaning gas distribution chamber is located inside the lifting pin mounting plate and is used to receive and distribute cleaning gas. A cleaning gas inlet pipe is used to introduce cleaning gas into the cleaning gas distribution chamber; A cleaning gas outlet is provided on the lifting pin mounting plate and communicates with the cleaning gas distribution chamber, used to deliver the cleaning gas to the surrounding area of ​​the lifting pin mounting plate.

2. The semiconductor process chamber cleaning gas delivery structure according to claim 1, characterized in that, The cleaning gas distribution chamber is an annular space surrounding the base support.

3. The semiconductor process chamber cleaning gas delivery structure according to claim 2, characterized in that, Multiple cleaning gas outlets are provided at intervals along the annular space.

4. The semiconductor process chamber cleaning gas delivery structure according to claim 3, characterized in that, The inner and / or outer sides of the lifting pin mounting plate are provided with cleaning gas outlets.

5. The semiconductor process chamber cleaning gas delivery structure according to claim 2, characterized in that, The upper end of the lifting pin mounting plate is provided with a cleaning gas outlet, which is offset from the position of the lifting pin.

6. The semiconductor process chamber cleaning gas delivery structure according to claim 1, characterized in that, The distribution of cleaning gas is controlled by changing the size of the cleaning gas outlet according to its location.

7. The semiconductor process chamber cleaning gas delivery structure according to claim 1, characterized in that, The distribution of cleaning gas is controlled by changing the number of cleaning gas outlets according to their location.

8. The semiconductor process chamber cleaning gas delivery structure according to claim 1, characterized in that, The distribution of cleaning gas is controlled by changing the tilt angle and direction of the cleaning gas outlet according to its location.

9. The semiconductor process chamber cleaning gas delivery structure according to claim 1, characterized in that, Each cleaning gas outlet is porous.

10. The semiconductor process chamber cleaning gas delivery structure according to claim 2, characterized in that, The cleaning gas outlet is a continuous annular slot or slit; Alternatively, the cleaning gas outlet may be an intermittent annular slot or slit.

11. The semiconductor process chamber cleaning gas delivery structure according to claim 1, characterized in that, The cleaning gas outlet is used to form an air curtain of purging gas outside the cleaning process, and the air curtain is used to prevent contaminants from clogging the cleaning gas outlet.

12. The semiconductor process chamber cleaning gas delivery structure according to claim 1, characterized in that, The upper end of the lifting pin mounting plate has an overflow prevention structure.

13. The semiconductor process chamber cleaning gas delivery structure according to claim 12, characterized in that, The anti-overflow structure is a barrier at the upper end of the lifting pin mounting plate used to change the straight flow direction of the gas flowing out of the cleaning gas outlet.

14. The semiconductor process chamber cleaning gas delivery structure according to claim 12, characterized in that, The anti-overflow structure is a guide wall at the upper end of the lifting pin mounting plate that guides the flow direction of the cleaning gas.

15. The semiconductor process chamber cleaning gas delivery structure according to claim 12, characterized in that, The anti-overflow structure refers to the stepped design of the cleaning gas outlet at the upper end of the lifting pin mounting plate.

16. The semiconductor process chamber cleaning gas delivery structure according to claim 12, characterized in that, The anti-overflow structure refers to the cleaning gas outlet at the upper end of the lifting pin mounting plate being in a labyrinth form.

17. The semiconductor process chamber cleaning gas delivery structure according to claim 1, characterized in that, When the lifting pin mounting plate descends to the bottom of the process chamber, the cleaning gas inlet pipe is connected to the cleaning gas distribution chamber.

18. The semiconductor process chamber cleaning gas delivery structure according to claim 17, characterized in that, The lower end of the lifting pin mounting plate is open.

19. The semiconductor process chamber cleaning gas delivery structure according to claim 17, characterized in that, The lower end of the lifting pin mounting plate has an air inlet that communicates with the cleaning gas distribution chamber, and the upper end of the cleaning gas inlet pipe is aligned with and inserted into the air inlet of the lifting pin mounting plate.

20. The semiconductor process chamber cleaning gas delivery structure according to claim 17, characterized in that, The lower end of the lifting pin mounting plate has a cleaning gas outlet and an air inlet. The lifting pin mounting plate is lowered to a gap with the bottom plate of the chamber, and the upper end of the cleaning gas inlet pipe is aligned with and inserted into the air inlet of the lifting pin mounting plate.

Images