Process chamber and lining cleaning method

Abstract

The invention provides a process chamber and a lining cleaning method. The process chamber comprises a chamber body, a base, a lining and a switching device, wherein the base is grounded; the lining is arranged in the cavity; the switching device is arranged outside the lining and has a first state and a second state; in the first state of the switching device, the lining is conducted with the ground wire through the switching device; and in the second state of the switching device, the lining is conducted with the external power supply through the switching device so as to ionize the process gas in the cavity and remove the thin film deposited on the surface of the lining by utilizing plasma formed by ionization, so that the situation that the thin film on the surface of the lining is accumulated too thick, and consequently a plating layer of the lining is peeled off is avoided.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of semiconductor process equipment, and particularly relates to a process chamber and an inner liner cleaning method. BACKGROUND

[0002] In the field of semiconductor manufacturing, the physical vapor deposition (PVD) method is widely used due to its simple structure, stable process, and the prepared film layer having good uniformity and stable properties. The process principle of the PVD equipment is to excite the process gas in the chamber into plasma, and to use the plasma to sputter the target material located at the top of the chamber, so that the target material is deposited on the substrate surface placed on the susceptor, thereby depositing a thin film on the substrate surface. The target material will not only be deposited on the substrate surface, but also on the inner liner surface. Moreover, as the process proceeds, the target material will be continuously consumed, and the thin film deposited on the inner liner surface will become thicker and thicker.

[0003] Since the inner liner surface is usually plated with a tungsten thin film to prevent leakage, and the tungsten thin film has large stress and poor adhesion, as the sidewall thin film accumulates and becomes thicker, the internal stress of the thin film accumulates, which may cause the plating layer to fall off, thereby causing the process particles to exceed the standard. In order to avoid this problem, frequent cleaning of the chamber is required, which results in high maintenance cost. SUMMARY

[0004] The present application provides a process chamber and an inner liner cleaning method, which aims to solve the problem of surface plating layer peeling caused by excessive accumulation of thin film deposition on the inner liner surface.

[0005] In a first aspect, the present application provides a process chamber, comprising a cavity and a susceptor, wherein the susceptor is grounded; and further comprising:

[0006] an inner liner arranged inside the cavity;

[0007] a switching device arranged outside the inner liner, having a first state and a second state; in the first state of the switching device, the inner liner is conducted with the ground wire through the switching device;

[0008] in the second state of the switching device, the inner liner is conducted with an external power supply through the switching device, so as to ionize the process gas in the cavity and remove the thin film deposited on the surface of the inner liner by the ionized plasma.

[0009] Optionally, the switching device comprises:

[0010] a bidirectional switch component arranged at the outer circumferential side of the inner liner, the bidirectional switch component having a fixed end and a movable end; the fixed end of the bidirectional switch component is electrically connected with the inner liner;

[0011] The first contact is connected to the ground wire.

[0012] The second contact is electrically connected to the external power supply via a power supply lead;

[0013] In the first state, the movable end of the bidirectional switch component is electrically connected to the first contact; in the second state, the movable end of the bidirectional switch component is electrically connected to the second contact.

[0014] Optionally, the switching device further includes:

[0015] A driver is disposed on the outer periphery of the liner and is communicatively connected to an external signal source. The driver is used to drive the bidirectional switch component to switch between the first contact and the second contact according to the external signal.

[0016] Optionally, the switching device further includes:

[0017] A control lead is provided, one end of which is connected to the signal receiving end of the driver, and the other end is led out from the cavity. The control lead is used to input control signals so that the driver drives the bidirectional switch component to move.

[0018] Optionally, the process chamber further includes:

[0019] An adapter ring is fixedly connected to the side wall of the cavity and electrically connected to the cavity; the cavity is grounded; the inner edge of the adapter ring is located inside the cavity;

[0020] An insulating ring is fixedly connected to the adapter ring; the bottom surface of the upper edge of the inner liner overlaps with the top surface of the insulating ring; an installation groove is provided in the insulating ring, and the installation groove is respectively connected to the power supply lead and the surface of the adapter ring; the bidirectional switch component is disposed inside the installation groove, and the first contact is electrically connected to the surface of the adapter ring.

[0021] Optionally, there may be multiple switching devices, and the multiple switching devices may be evenly distributed along the circumference of the lining.

[0022] Optionally, both the power supply lead and the control lead are located on the outer periphery of the liner;

[0023] The process chamber also includes an insulating tube; the insulating tube at least covers the surface of the portions of the power supply lead and the control lead located inside the chamber.

[0024] Optionally, the process chamber further includes:

[0025] A shielding plate is used to cover the bearing surface of the base when the switching device is in the second state, so as to shield the bearing surface of the base.

[0026] Secondly, the present invention also provides a lining cleaning method, applied to the process chamber as described above; comprising:

[0027] During the non-process stage, the control switching device is in the second state and process gas is introduced into the cavity.

[0028] Turn on an external power source to ionize the process gas and attract plasma to bombard the surface of the liner.

[0029] Optionally, before the step of the control switching device being in the second state, the lining cleaning method further includes:

[0030] The usage time of the target material in the process chamber is obtained, and it is determined whether the current usage time of the target material has reached the preset time.

[0031] If so, then continue with the step of putting the control switching device in the second state;

[0032] If not, the switching device is controlled to be in the first state.

[0033] Optionally, before the step of the control switching device being in the second state, the lining cleaning method further includes:

[0034] Place the shielding plate above the bearing surface of the base to shield the bearing surface of the base.

[0035] The present invention has the following beneficial effects:

[0036] The process chamber provided in this embodiment of the invention, by adding a switching device, allows the liner to be connected to an external power source in its second state. The external power source ionizes the process gas within the chamber, attracting the ionized plasma to bombard the liner surface, thereby removing the thin film deposited on the liner surface. This prevents the film from accumulating too thickly and causing the liner's coating to peel off. Furthermore, it eliminates the need to remove the liner from the process chamber, simplifying the liner cleaning process and reducing cleaning costs. In its first state, the switching device can connect the liner to ground to meet the process conditions of the deposition process. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of a process chamber in related technologies;

[0038] Figure 2A This is a partial cross-sectional view of the inner substrate end region in the related technology;

[0039] Figure 2B for Figure 2A Enlarged view of region X in the middle;

[0040] Figure 3 This is a schematic diagram of the structure of the process chamber proposed in an embodiment of the present invention;

[0041] Figure 4 This is a circuit diagram of the switching device proposed in an embodiment of the present invention;

[0042] Figure 5 This is a top view of the insulating ring and switching device proposed in an embodiment of the present invention;

[0043] Figure 6 This is a partial cross-sectional view of the connection between the insulating ring and the matching ring according to an embodiment of the present invention;

[0044] Figure 7 This is a flowchart of a lining cleaning method proposed in an embodiment of the present invention. Detailed Implementation

[0045] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0046] It is understood that the specific embodiments and accompanying drawings described herein are merely for explaining the invention and are not intended to limit the invention.

[0047] It is understood that, without conflict, the various embodiments of the present invention and the features thereof can be combined with each other.

[0048] It is understood that, for ease of description, the accompanying drawings of this invention only show the parts related to the embodiments of this invention, while the parts unrelated to the embodiments of this invention are not shown in the drawings.

[0049] It is understood that, without conflict, the functions and steps marked in the flowcharts and block diagrams of the embodiments of the present invention may occur in a different order than that marked in the accompanying drawings.

[0050] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

[0051] like Figure 1As shown, a PVD process chamber typically includes: a chamber 01, a base 02, a shielding disk 03, a process retaining ring 04, an inner liner 05, and a deposition ring 06. The deposition ring 06 surrounds the outer periphery of the base 02, the inner liner 05 surrounds the base 02, and the process retaining ring 04 is pressed above the annular gap between the deposition ring 06 and the inner liner 05. Thus, the base 02, deposition ring 06, and inner liner 05 divide the interior of the chamber 01 into an upper sub-chamber 01a and a lower sub-chamber 01b. The deposition process is primarily carried out in the upper sub-chamber 01a. The deposition ring 06 and the shielding disk 03 prevent metal sputtered from the surface of the target material 07 from falling into the lower sub-chamber 01b. The shielding disk 03 is positioned above the base 02 to prevent metal sputtered from the surface of the target material 07 from falling onto the surface of the base 02. As can be seen, the inner surface of the liner 05 is exposed to the process environment. Therefore, the target material 07 will not only be deposited on the substrate surface, but also on the surface of the liner 05. Moreover, as the process proceeds, the target material 07 will be continuously consumed, and the metal material sputtered from the surface of the target material 07 will be continuously deposited on the tungsten coating 08 on the surface of the liner 05, causing the tungsten coating 08 to become thicker and thicker.

[0052] like Figure 1 As shown, the liner 05 includes a vertically extending cylindrical portion, an upper edge disposed at the top of the cylindrical portion, and a lower edge disposed at the bottom of the cylindrical portion; moreover, as Figure 2A As shown, to improve the strength of the inner lining 05, the bottom end of the cylindrical portion of the existing inner lining 05 is usually thickened; by Figure 2B As can be seen, the thickened area forms a stepped structure with other areas on the inner surface. Furthermore, as the deposition process progresses, a significant amount of metal is deposited on the surface of this stepped structure, resulting in a thicker tungsten plating 08 at this location. The inner circumferential surface of the cylindrical portion of the liner 05 is typically coated with a tungsten plating 08 to prevent glow leakage. However, the tungsten plating 08 itself has high stress and poor adhesion. As the process continues, metal material sputtered from the target continuously deposits onto the tungsten plating 08. Consequently, the surface tension of the tungsten plating 08 increases. With the accumulation of the tungsten plating 08's thickness, its internal tension also increases, potentially leading to peeling of the tungsten plating 08. This can result in excessive levels of contaminant particles within the chamber, necessitating cleaning of the process chamber.

[0053] To prevent the metal plating on the surface of the liner 05 from peeling off, related technologies typically employ a stepped structure with a thinned cylindrical section or increase the frequency of removing the liner 05 for separate cleaning. However, the former leads to a decrease in the strength of the cylindrical section of the liner 05, which in turn greatly increases the risk of deformation and reduces its service life. The latter, on the other hand, increases maintenance costs due to frequent cleaning and reduces the process utilization rate of the process chamber, thereby increasing the overall process cost.

[0054] Furthermore, in some related technical solutions, nitrogen (N2) pipelines can be added to the process chamber to periodically nitrid the inner surface of the liner 05, thereby forming a highly adhesive tungsten nitride layer on the surface of the tungsten metal coating and reducing the risk of peeling off the tungsten metal coating. However, nitrogen can easily poison the target material 07, leading to the failure of the target material 07 and resulting in process failure.

[0055] Please refer to Figure 3 To address the aforementioned technical problems, this embodiment provides a process chamber, including a chamber body 1 and a base 2. Specifically, the chamber body 1 has a sealed accommodating space to accommodate other components of the process chamber for the execution of the process; the base 2 is disposed inside the chamber and is used to support the substrate for the deposition process. The base 2 is grounded.

[0056] like Figure 3 As shown, the process chamber also includes a liner 3 and a switching device 4. The liner 3 is disposed inside the chamber 1; specifically, the liner 3 surrounds the base 2 and is used to prevent metal material sputtered from the surface of the target material 8 from falling back down. The switching device 4 is disposed outside the liner 3. It should be noted that, as... Figure 3 As shown, the outside of the liner 3 refers to the outer periphery of the cylindrical part of the liner 3 and the entire lower side of the liner 3.

[0057] The switching device 4 has a first state and a second state. In the first state, the liner 3 is connected to the ground wire through the switching device 4. Specifically, during the deposition process, the switching device 4 can be in the first state to ground the liner 3, thereby avoiding interference with the electric field inside the cavity 1 and ensuring that most of the sputtered particles are deposited on the substrate surface. In the second state, the liner 3 is connected to the external power supply 7 through the switching device 4. Since the base 2 remains grounded, there is a certain potential difference between the liner 3 and the base 2. This potential difference satisfies the requirement that the electric field formed between the liner 3 and the base 2 can ionize the process gas in the cavity 1 and attract the ionized plasma to bombard the surface of the liner 3. The plasma bombardment removes the thin film deposited on the surface of the liner 3, thereby thinning the thin film on the surface of the liner 3 and preventing the film from becoming too thick and causing the coating on the surface of the liner 3 to peel off. In this way, it is not necessary to remove the liner 3 from the process chamber for cleaning, which simplifies the cleaning process of the liner 3 and reduces the cleaning cost of the liner 3, thereby reducing the overall maintenance cost of the process chamber.

[0058] For example, after switching device 4 to its second state, process gas can be introduced into cavity 1, and the external power supply 7 can be controlled to output a corresponding voltage. For example, the process gas can be argon (Ar), and the external power supply 7 can output a negative voltage so that the surface potential of the liner 3, which is electrically connected to the external power supply 7, is lower than that of the base 2. Thus, under the effect of the potential difference between the liner 3 and the base 2, the argon gas will be ionized and generate argon ions (Ar+). Moreover, the negatively charged liner 3 can attract positive ions to accelerate and bombard its surface, causing the thin film deposited on the surface of the liner 3 to be sputtered and leave the surface of the liner 3. It should be noted that the plasma used to bombard the thin film should satisfy the following condition: it can remove the thin film on the surface of the liner 3 without removing the coating on the surface of the liner 3, so as to achieve the removal of the thin film while avoiding damage to the coating on the surface of the liner 3.

[0059] For example, the external power supply 7 can be a direct current (DC) power supply; or, the external power supply 7 can also be a radio frequency (RF) power supply.

[0060] For example, the process chamber provided in this embodiment can be as follows: Figure 3 The illustrated magnetron sputtering vapor deposition process chamber has a magnetron device 12 disposed at the top of the chamber 1. Alternatively, the process chamber may be other physical vapor deposition process chambers with an inner liner 3 structure.

[0061] During the process of bombarding the surface of the liner 3 with plasma, the sputtered material from the thin film deposited on the surface of the liner 3 may deposit on the surface of any component inside the cavity 1. Therefore, to protect the base 2, in some embodiments, the process chamber also includes a shielding disk 9, which covers the bearing surface of the base 2 when the switching device 4 is in the second state, thereby protecting the bearing surface of the base 2 and preventing the sputtered material from depositing on the surface of the base 2. This ensures that the base 2 can continue to participate in subsequent deposition processes, thus extending the service life of the base 2. Moreover, after the sputtering process of the liner 3 surface is completed, the shielding disk 9 can be rotated and moved to a storage cavity located on the side of the process chamber using a rotating arm, so that the bearing surface of the base 2 is exposed, allowing the substrate to be placed on the bearing surface.

[0062] It should be noted that, as Figure 3 As shown, some of the material sputtered from the thin film deposited on the surface of the liner 3 may also be deposited on the surface of the target 8. Before the subsequent deposition process begins, the target 8 is usually cleaned to remove the oxide layer that has formed on its surface due to a period of inactivity. During this process, the material deposited on the surface of the target 8 can be removed along with the oxide layer without affecting the normal progress of the subsequent deposition process.

[0063] For example, the surface of the shielding disk 9 can be spray-treated to increase the roughness of the protective surface, thereby improving the adsorption of material on its surface. This allows the material sputtered from the surface film of the liner 3 to be deposited on the surface of the shielding disk 9 as much as possible, reducing contamination of the gas environment inside the cavity 1. Furthermore, the spray-treatment can be performed only on the side of the shielding disk 9 away from the base 2, or both sides of the shielding disk 9 can be spray-treated.

[0064] For example, in practical applications, the shielding disk 9 can be replaced after a preset service life has been used, so as to replace the shielding disk 9 periodically. Specifically, the preset service life can be determined through multiple tests to ensure that the replacement frequency of the shielding disk 9 is not too high, provided that the sputtered material can be tightly deposited on the surface of the shielding disk 9.

[0065] In some embodiments, such as Figure 4 As shown, the switching device 4 includes a bidirectional switch component 41, a first contact A, and a second contact B. The bidirectional switch component 41 is disposed on the outer periphery of the inner liner 3 and has a movable end and a fixed end. The fixed end is electrically connected to the inner liner 3, and the movable end can move between the first contact A and the second contact B. The first contact A is electrically connected to the ground wire; the second contact B is electrically connected to the external power supply 7 via a power supply lead 43. In the first state, the movable end of the bidirectional switch component 41 is electrically connected to the first contact A to connect the inner liner 3 to the ground wire, thereby grounding the inner liner 3. In the second state, the movable end of the bidirectional switch component 41 is electrically connected to the second contact B to connect the inner liner 3 to the external power supply 7, thereby creating a potential difference between the inner liner 3 and the base 2.

[0066] For example, the switching device 4 may include a single-pole double-throw switch. Correspondingly, the bidirectional switching component 41 may be a rotatable movable knife switch.

[0067] In some embodiments, the switching device 4 further includes a driver for driving the operation of the bidirectional switching component 41. Specifically, the driver is disposed on the outer periphery of the liner 3, specifically on the outer periphery of the cylindrical portion of the liner 3; and the driver is communicatively connected to an external signal source 10. The driver is used to drive the bidirectional switching component 41 to switch between the first contact A and the second contact B according to the external signal. This enables automatic control of the operation of the bidirectional switching component 41, thereby eliminating the need to open the process chamber or for operators to manually switch the position of the bidirectional switching component 41, further reducing the number of openings and thus further reducing equipment maintenance costs.

[0068] In some embodiments, such as Figure 3 and Figure 4As shown, the switching device 4 also includes a control lead 42. One end of the control lead 42 is connected to the signal receiving end of the driver, and the other end is led out from the cavity 1. The control lead 42 is used to input control signals so that the driver drives the bidirectional switching component 41 to move.

[0069] In other feasible embodiments, the aforementioned external signal source may also be wirelessly connected to the aforementioned driver.

[0070] For example, the switching device 4 may include a relay; specifically, the magnetic control part of the relay may be used as the aforementioned driver, and the signal receiving end of the relay may be connected to the aforementioned control lead 42 so that the magnetic control part, in response to the control signal, attracts the switch of the relay to switch between two contacts.

[0071] In some embodiments, such as Figure 3 As shown, the process chamber typically includes an adapter ring 5 and an insulating ring 6. The adapter ring 5 is fixedly connected to the side wall of the chamber 1 and electrically connected to the chamber 1, and the chamber 1 is grounded. Specifically, as shown... Figure 3 As shown, the bottom surface of the adapter ring 5 abuts against the top surface of the side wall of the cavity 1, the top cover of the cavity 1 is pressed on the top surface of the adapter ring 5, and the inner edge of the adapter ring 5 is located inside the cavity 1, that is, the inner edge of the adapter ring 5 protrudes relative to the inner circumferential surface of the cavity 1 so that the target material 8 can be disposed on the top surface of the adapter ring 5.

[0072] The insulating ring 6 is fixedly connected to the adapter ring 5; the bottom surface of the upper edge of the inner liner 3 overlaps with the top surface of the insulating ring 6; the insulating ring 6 has a mounting groove 61, which is connected to the power supply lead 43 and the surface of the adapter ring 5 respectively; the bidirectional switch component 41 is disposed inside the mounting groove 61; the first contact A is electrically connected to the surface of the adapter ring 5, so as to be electrically connected to the grounded cavity 1 through the adapter ring 5. In this way, by driving the bidirectional switch component 41 to move in the mounting groove 61, the bidirectional switch component 41 can be electrically connected to the adapter ring 5 or to the power supply lead 43, thereby grounding the inner liner 3 or connecting the inner liner 3 to the external power supply 7.

[0073] For example, the mounting groove 61 can also be connected to the side wall surface of the cavity 1 and the power supply lead 43 respectively; and the first contact A is electrically connected to the side wall surface of the cavity 1; in this way, when the movable end of the bidirectional switch component 41 contacts the side wall surface of the cavity 1, the liner 3 can be grounded through electrical connection with the side wall of the cavity 1.

[0074] Furthermore, in some embodiments, the aforementioned driver may also be disposed in the aforementioned mounting slot 61; correspondingly, the aforementioned control lead 42 may also be connected to the mounting slot 61 to facilitate communication with the driver. In this way, by disposing of both the driver and the bidirectional switch component 41 in the mounting slot 61, the side wall of the mounting slot 61 can be used to protect the driver and the bidirectional switch component 41, thereby reducing the risk of damage to both and extending their service life.

[0075] For example, such as Figure 6 As shown, the adapter ring 5 and the insulating ring 6 are connected and fixed by screws and nuts. Specifically, the adapter ring 5 has multiple threaded holes on its bottom surface, and the insulating ring 6 has through holes that correspond one-to-one with the multiple threaded holes; one end of the screw can pass through the through hole and extend into the threaded hole and be threadedly connected thereto, and the other end of the screw can be threadedly connected to the nut, so as to clamp and fix the insulating ring 6 between the nut and the adapter ring 5.

[0076] In some embodiments, such as Figure 3 As shown, both the power supply lead 43 and the control lead 42 are located on the outer periphery of the liner 3, that is, on the outer periphery of the cylindrical portion of the liner 3. The process chamber also includes an insulating tube 11, which at least covers the surface of the portions of the power supply lead 43 and the control lead 42 located inside the chamber 1 to protect the power supply lead 43 and the control lead 42 and electrically isolate other components inside the chamber 1 from the power supply lead 43 and the control lead 42, thereby preventing interference with the normal operation of other components.

[0077] For example, the power supply lead 43 and the control lead 42 can be led out through a through hole opened in the bottom region of the side wall, and the inner circumferential surface of the through hole and the power supply lead 43 and the control lead 42 also have a sealing structure to ensure the sealing of the cavity 1 environment.

[0078] In other feasible embodiments, the switching device 4 may not employ the aforementioned active switch structure; it may instead consist of a first lead and a second lead. Specifically, one end of the first lead is electrically connected to the surface of the inner liner 3, and the other end is led out from the cavity 1 and disconnectably connected to the ground wire; one end of the second lead is electrically connected to the surface of the inner liner 3, and the other end is led out from the cavity 1 and disconnectably connected to the external power supply 7. Thus, by connecting the first lead to the ground wire and disconnecting the second lead from the external power supply 7, the switching device 4 can be placed in the aforementioned first state, thereby grounding the inner liner 3; alternatively, by disconnecting the first lead to the ground wire and connecting the second lead to the external power supply 7, the switching device 4 can be placed in the aforementioned second state, thereby connecting the inner liner 3 to the external power supply 7. The voltage supplied to the inner liner 3 by the external power supply can then be used to ionize the process gas within the cavity 1, attracting the generated plasma to bombard the surface of the inner liner 3.

[0079] In some embodiments, such as Figure 5As shown, there are multiple switching devices 4, which are evenly distributed around the circumference of the inner liner 3. When the switching device 4 is in the second state, the voltage applied to the inner liner 3 is evenly distributed, thereby evenly distributing the potential difference between the inner liner 3 and the base 2, and thus uniformly removing the film formed on the surface of the inner liner 3. Specifically, the number of switching devices 4 can be set according to actual process requirements; for example, there can be eight switching devices 4.

[0080] For example, multiple switching devices 4 can share the same external power supply 7 to further improve the uniformity of the potential difference distribution between the liner 3 and the base 2.

[0081] As another technical solution, this embodiment also provides a lining cleaning method, as described above for the process chamber. Figure 7 As shown, the lining cleaning method includes:

[0082] S1. During the non-process stage, the control switching device is in the second state, and process gas is introduced into the cavity.

[0083] S2. Turn on the external power supply to ionize the process gas and attract plasma to bombard the surface of the liner.

[0084] It should be noted that the order of the control switching device being in the second state and the process gas being introduced into the cavity is not important, because before the external power is turned on, neither the first nor the second state of the switching device will generate a potential difference with the grounded base.

[0085] For example, an external signal source can be used to control the movable end of the bidirectional switch component in the switching device to move to a position that contacts the adapter ring, so as to switch the switching device to the second state.

[0086] In some embodiments, before the step of "controlling the switching device to be in the second state", i.e. before step S1, the lining cleaning method further includes:

[0087] S01. Obtain the usage time of the target material in the process chamber and determine whether the current usage time of the target material has reached the preset time.

[0088] If so, continue with the step of controlling the switching device to be in the second state;

[0089] If not, the control switching device is in the first state.

[0090] This allows for periodic cleaning of the lining.

[0091] Specifically, the aforementioned preset duration is the actual usage time of the target material in the process; for example, the aforementioned liner cleaning is performed once the target material usage time reaches 200 kWh. Moreover, after the target material reaches its service life, the cavity needs to be opened to replace the target material and replace or remove the liner for cleaning.

[0092] In some embodiments, before the step of "controlling the switching device to the second state" described above, i.e. before step S1, the lining cleaning method further includes:

[0093] S02. Place the shielding disk above the bearing surface of the base to prevent the sputtered material from depositing on the base surface.

[0094] In some embodiments, the switching device can be controlled to be in a first state before the subsequent deposition process begins.

[0095] In some embodiments, after the plasma bombardment of the liner is completed, i.e. after step S2 is completed, the liner cleaning method further includes:

[0096] S3. Turn off the external power supply to stop attracting plasma to bombard the liner; and control the switching device to the first state so that the liner can be grounded through the switching device.

[0097] S4. Move the shielding plate to the receiving cavity located on the side of the process chamber to complete the liner cleaning process. In this way, by combining the above steps S3 and S4, the liner potential and the shielding plate can be reset to prepare for the next process stage.

[0098] In some embodiments, the above method further includes:

[0099] Continuously monitor the particle size inside the cavity and determine whether the detected value reaches the preset particle size threshold; if so, continue with the subsequent steps; specifically, if the determination result is yes, it indicates that the film deposited on the inner liner surface is too thick, and the process cavity must be opened and cleaned.

[0100] If not, continue with the above steps to detect and determine the particle size inside the cavity.

[0101] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A process chamber, comprising: A cavity and a base, the base being grounded; characterized in that further comprising: An inner liner arranged inside the cavity; A switching device arranged outside the inner liner, having a first state and a second state; in the first state of the switching device, the inner liner is conductive to ground through the switching device; In the second state of the switching device, the inner liner is conductive to an external power source through the switching device, to ionize a process gas inside the cavity and remove a thin film deposited on the surface of the inner liner by a plasma formed by ionization.

2. The process chamber of claim 1, wherein, The switching device comprises: A bidirectional switch component arranged at the outer circumferential side of the inner liner; the bidirectional switch component has a fixed end and a movable end; the fixed end of the bidirectional switch component is electrically connected to the inner liner; A first contact electrically connected to ground; A second contact electrically connected to the external power source through a power supply lead; In the first state, the movable end of the bidirectional switch component is electrically connected to the first contact; in the second state, the movable end of the bidirectional switch component is electrically connected to the second contact.

3. The process chamber of claim 2, wherein, The switching device further comprises: A driver arranged at the outer circumferential side of the inner liner and in communication connection with an external signal source, the driver being used to drive the bidirectional switch component to switch between the first contact and the second contact according to the external signal.

4. The process chamber of claim 3, wherein, The switching device further comprises: A control lead, one end of the control lead being connected to the signal receiving end of the driver, and the other end being led out from the cavity, the control lead being used to input a control signal to make the driver drive the bidirectional switch component to move.

5. The process chamber of claim 2, wherein, The process chamber further comprises: An adapter ring fixedly connected to the sidewall of the cavity and electrically connected to the cavity; the cavity is grounded; the inner edge of the adapter ring is located inside the cavity; An insulating ring fixedly connected to the adapter ring; the bottom surface of the upper edge of the inner liner overlaps the top surface of the insulating ring; an installation groove is formed in the insulating ring, the installation groove is respectively in communication with the surface of the power supply lead and the adapter ring; the bidirectional switch component is arranged inside the installation groove, and the first contact is electrically connected to the surface of the adapter ring.

6. The process chamber according to claim 1, characterized in that: The number of switching devices is multiple, and multiple switching devices are distributed circumferentially along the inner liner.

7. The process chamber of claim 4, wherein, The power supply lead and the control lead are both arranged at the outer circumferential side of the inner liner; The process chamber further comprises an insulating tube; the insulating tube covers at least the surface of the part of the power supply lead and the control lead located inside the cavity.

8. The process chamber of claim 1, wherein, The process chamber further comprises: A shielding disc used to cover the load surface of the base when the switching device is in the second state, to shield the load surface of the base.

9. A method for cleaning a liner applied to a process chamber as claimed in any one of claims 1-8; wherein, Comprising: In a non-process phase, controlling the switching device to be in the second state, and introducing a process gas into the cavity; Turning on the external power source to ionize the process gas and attract plasma to bombard the surface of the inner liner.

10. The method of claim 9, wherein, Before the step of controlling the switching device to be in the second state, further comprising: Obtaining the use time length of a target material in the process chamber, and determining whether the current use time length of the target material reaches a preset time length; If so, the step of controlling the switching device in the second state is continued. If not, the switching device is controlled in the first state.

11. The method of claim 9, wherein, Before the step of controlling the switching device in the second state, the method further comprises: placing a masking disc above the load surface of the base to mask the load surface of the base.

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