A method for surface treatment after PAD etching and a semiconductor component

Abstract

The present invention discloses a method for surface treatment after PAD etching and a semiconductor component. The method includes the following steps: introducing process gas into the chamber, and adjusting the remaining parameters according to one or two of the swing valve position, gas flow rate, and process pressure to maintain the stable state of the chamber; performing ion bombardment for a preset duration at a preset radio frequency power to strip all or part of the photoresist. The present invention can clean the products on the wafer surface without high temperature, reduce F ion corrosion, is also beneficial to avoid the problems of photoresist collapse and photoresist smearing caused by the increase of the chamber temperature, is convenient for removing the harder photoresist on the surface, and does not require chamber modification and does not involve the structural limitations of the product itself, solving the problem that the products are difficult to clean and the removal of the photoresist is affected after cleaning, and has a wide range of applications.

Description

Technical Field

[0001] The present invention relates to the field of chip manufacturing, and particularly to a method for surface treatment after PAD etching and a semiconductor component. Background Art

[0002] In the process of chip manufacturing, the passivation layer (PAD for short) needs to complete functions such as scratch prevention, shock prevention, moisture prevention, and even radiation prevention. It is usually composed of a dielectric film with a thickness of 0.5 - 1.5 um, generally including silicon nitride, silicon oxide, silicon oxynitride, or a stack of these films. Due to the relatively thick PAD, there are more polymers in the etching products. There are a large number of C and F elements in the polymers, which adhere to the surface of the product pattern and the inner wall of the etching chamber. This may accelerate the corrosion of aluminum on the surface of the product pattern or cause equipment abnormalities, and thus equipment cavity opening maintenance and cleaning must be carried out.

[0003] At the same time, due to the relatively thick PAD film layer, in order to reduce the process time and improve the production capacity, the etching power is usually increased and the bombardment of the product is enhanced. As a result, the photoresist serving as the etching mask layer hardens on the surface due to high-energy and long-time etching, and it is somewhat difficult to remove the photoresist. Therefore, the removal of the etching products and the removal of the photoresist are the two major difficulties currently faced.

[0004] For the products on the wafer surface, the existing removal methods are to remove them by microwave dry stripping plus wet cleaning, both of which belong to chemical reactions and there is no bombardment removal means; or by adding a small amount of oxygen during the etching process to oxidize and remove some of the generated polymers during the etching process; or by adjusting the formula of the wet cleaning to sacrifice a small amount of aluminum for polymer stripping; or by means of endpoint detection, when etching the TiN layer, changing to conditions with less bombardment to reduce the attachment of F ions to the Al surface.

[0005] However, adding a small amount of oxygen during the etching process will increase the loss of the photoresist. For parts with larger pattern steps, the thickness of the photoresist itself is relatively thin. After the etching increases the requirement for the photoresist thickness, the position with larger steps is prone to etching due to insufficient photoresist protection, which may lead to product defects. The method of adjusting the wet cleaning formula will sacrifice a thin layer of aluminum, and if there is a TiN film layer in the product film layer design, it is very easy to cause corrosion and internal etching of the TiN. The success rate of endpoint detection depends on factors such as the product design open ratio, TiN film layer, etching rate, etc., which are not conducive to the realization of the product's corrosion resistance.

[0006] For the ashing after PAD, the prior art usually increases the ashing power in the asher or adds fluorine-based gas to remove the photoresist after PAD etching. When removing the photoresist by increasing the ashing power, it is easy for the temperature on the wafer surface to rise abnormally due to high power and poor heat dissipation, which may cause the photoresist to coke and denature, and the coked photoresist is more difficult to remove. By adding fluorine-based gas, the hardened photoresist can be removed, but the fluorine-based gas will cause loss of the dielectric layer. At the same time, the residual F ions on the metal surface may cause corrosion of the metal by the F ions.

[0007] Therefore, how to ensure both the cleaning effect of the product and the removal effect of the photoresist to reduce F ion corrosion and improve the product yield is a technical problem that urgently needs to be solved at present. Summary of the Invention

[0008] Aiming at the problems in the prior art that the product is difficult to clean and the removal of the photoresist is affected after cleaning, the present invention provides a method for surface treatment after PAD etching and a semiconductor component. By introducing process gas into the chamber and adjusting relevant parameters, in-situ ashing is carried out under expected control conditions. Without high temperature, the product on the wafer surface can be cleaned, F ion corrosion can be reduced, and it is also beneficial to avoid collapse and smearing of the photoresist caused by high chamber temperature. It is convenient to remove the harder photoresist on the surface, and there is no need to modify the chamber, nor does it involve the structural limitations of the product itself. The problems that the product is difficult to clean and the removal of the photoresist is affected after cleaning are solved, and the applicable range is wide.

[0009] The following are the technical solutions of the present invention.

[0010] A method for surface treatment after PAD etching includes the following steps:

[0011] Introduce process gas into the chamber, and adjust the remaining parameters according to one or two of the swing valve position, gas flow rate, and process pressure to keep the chamber state stable;

[0012] Perform ion bombardment for a preset duration at a preset radio frequency power to strip all or part of the photoresist.

[0013] The present invention belongs to in-situ degumming, that is, after the operation, the product is not removed, and degumming is directly carried out at the current station and the current machine. In the present invention, due to the relatively large amount of gas used and the limited pressure control ability of the vacuum gauge on the equipment, in order to achieve high-precision pressure control, it is necessary to comprehensively adjust the swing valve position, gas flow rate, and process pressure to ensure the stable state of the chamber. Due to the existence of bias voltage, the polymer will be oxidized and decomposed and discharged during the degumming process, and the F-containing gas in the lattice gap will also be displaced, greatly reducing the F content on the product surface. Without F ions on the surface as a catalyst, metallic aluminum will naturally oxidize to form a bright protective film of aluminum oxide and no longer undergo aluminum corrosion. At the same time, the plasma has a certain bombardment property and can relatively easily remove the hardened gum layer that is difficult to remove.

[0014] Preferably, the process gas includes oxygen or a mixed gas. When the process gas is a mixed gas, the proportion of oxygen in the mixed gas is not less than 50%. Oxygen is the main gas for in-situ degumming, and at the same time, the dissociation of oxygen can be promoted by introducing a small amount of nitrogen, thereby increasing the degumming effect of oxygen.

[0015] Preferably, adjusting the remaining parameters according to one or two of the swing valve position, gas flow rate, and process pressure includes:

[0016] Determine the gas flow rate and the swing valve position range, measure the first current pressure according to the upper limit value of the swing valve position and the gas flow rate, measure the second current pressure according to the lower limit value of the swing valve position and the gas flow rate, and determine the process pressure adjustment range with the first current pressure and the second current pressure as the upper and lower limits, and adjust the process pressure;

[0017] Or, determine the swing valve position range, measure the current swing valve position according to the current gas flow rate and the current pressure, and adjust the current gas flow rate and / or the current pressure until the current swing valve position meets the swing valve position range.

[0018] Preferably, the swing valve position is selected from 30% to 70%, the gas flow rate is selected from 600 to 1200 sccm, and the process pressure is selected from 30% to 95% of the extreme value of the pressure control range.

[0019] In the present invention, affected by the pumping speed of the molecular pump of the machine, generally a higher pressure control is required, and a relatively large pressure value within the pressure control range can be selected for setting. For example, if the pressure control range of the machine is 0 - 100 mt, the pressure parameter can be set to 80 - 95 mt; if the pressure control range of the machine is 0 - 500 mt, the pressure parameter can be set to 200 - 450 mt; if the pressure control range of the machine is 0 - 1 Torr, the appropriate pressure parameter can be selected according to the gas flow rate, and the selection range is 300 - 900 mt.

[0020] Preferably, the ion bombardment at a preset radio frequency power for a preset duration includes:

[0021] Determine the radio frequency power range according to the sensitivity of the PAD film to ion bombardment, select the preset radio frequency power from the radio frequency power range according to the photoresist thickness, the amount of photoresist removal, and the expected photoresist removal time, and perform ion bombardment with the expected photoresist removal time as the preset duration; or, determine the radio frequency power according to the sensitivity of the PAD film to ion bombardment, calculate the preset duration according to the determined radio frequency power, the photoresist thickness, and the amount of photoresist removal, and perform ion bombardment.

[0022] Preferably, the value range of the preset radio frequency power includes 500 - 1200 W, and the value range of the preset duration includes: 20 - 100 s.

[0023] Preferably, before introducing the process gas into the chamber, it further includes:

[0024] Discharge the residual gas inside the chamber by means of gas replacement.

[0025] Preferably, the gas used for gas replacement includes at least one of O2, N2, and He.

[0026] Preferably, after stripping all the photoresist, it further includes wet cleaning; after stripping part of the photoresist, it further includes dry photoresist removal and wet cleaning.

[0027] The present invention also provides a semiconductor element, and the semiconductor element is processed by the above method for surface treatment after a certain PAD etching during the manufacturing process.

[0028] The substantial effects of the present invention include:

[0029] After in-situ photoresist removal, due to the existence of the bias voltage, the polymer will be oxidized and decomposed and discharged during the photoresist removal process, and the F-containing gas in the lattice gaps will also be replaced by oxygen ions, greatly reducing the F content on the product surface. After subsequent conventional dry photoresist removal and wet cleaning, without F ions as catalysts on the surface, metallic aluminum will naturally oxidize to form a bright protective film of aluminum oxide, and aluminum corrosion will no longer occur.

[0030] Use the product wafer itself to protect the lower electrode, without the need to introduce a dummy wafer additionally, reducing the equipment handling time and the loss of the dummy wafer, and improving the equipment production capacity. The etching process is at a conventional temperature, and the chamber temperature does not require special heating, which is beneficial to avoiding photoresist collapse and smearing caused by high chamber temperature; the chamber area does not need to be increased either, reducing the occupied factory building area, increasing the equipment maintenance space, and reducing the maintenance difficulty. It ensures the cleanliness of the chamber environment, can effectively improve the equipment maintenance time, and improve the equipment production capacity.

[0031] Due to the low frequency band of the radio frequency source in the etching chamber, the oxygen plasma has a certain bombardment property, while the radio frequency source of the desoldering machine is in the microwave frequency band. Although the oxygen plasma concentration is high, its bombardment property is insufficient (a small bombardment property can ensure little damage to the product). Therefore, the oxygen plasma can relatively easily remove the hardened glue layer.

[0032] If partial desoldering is adopted, after removing the hardened photoresist inside the etching machine, the remaining photoresist is removed by a conventional desoldering machine, which can not only ensure that all the photoresist is removed cleanly, but also avoid damage to the surface dielectric film. Description of the Drawings

[0033] Figure 1 is a process flow chart of an embodiment of the present invention;

[0034] Figure 2 is another process flow chart of an embodiment of the present invention;

[0035] Figure 3 is a cross-sectional view of the product before desoldering according to an embodiment of the present invention;

[0036] Figure 4 is a cross-sectional view of the product after desoldering according to an embodiment of the present invention;

[0037] The figure includes: 1 - photoresist, 2 - etching buffer layer, 3 - metal layer, 4 - PAD film, 5 - lower product film. Detailed Embodiments

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will, in conjunction with the embodiments, clearly and completely describe the technical solutions. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0039] It should be understood that in various embodiments of the present invention, the magnitudes of the sequence numbers of the various processes do not mean the order of execution. The order of execution of the various processes should be determined by their functions and internal logics, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0040] It should be understood that in the present invention, "including" and "having" and any of their variations are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those clearly listed steps or units, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products, or devices.

[0041] It should be understood that in the present invention, "a plurality of" means two or more. " / or" is merely an association relationship describing associated objects, indicating that there can be three relationships. For example, A / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "Including A, B, and C" and "including A, B, C" mean that all of A, B, and C are included. "Including A, B, or C" means that one of A, B, and C is included. "Including A, B, and / or C" means that any one or any two or all three of A, B, and C are included.

[0042] The technical solution of the present invention will be described in detail below with specific embodiments. The embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0043] Embodiment 1:

[0044] A method for surface treatment after PAD etching, comprising the following steps:

[0045] Introduce process gas into the chamber, and adjust the remaining parameters according to one or two of the swing valve position, gas flow rate, and process pressure to maintain the stability of the chamber state;

[0046] Perform ion bombardment for a preset duration at a preset radio frequency power to strip part of the photoresist. After stripping part of the photoresist, dry photoresist removal and wet cleaning are also included. As Figure 1 shown is a process flow chart of this embodiment.

[0047] In this embodiment, the process gas can be selected as oxygen or a mixed gas. When the process gas is a mixed gas, the oxygen content in the mixed gas is not less than 50%. Oxygen is the main gas for in-situ photoresist removal, and at the same time, the dissociation of oxygen can be promoted by introducing a small amount of nitrogen, thereby increasing the photoresist removal effect of oxygen.

[0048] Preferably, the swing valve position is selected as 30% - 70%, the gas flow rate is selected as 600 - 1200 sccm, and the process pressure is selected as 30 - 95% of the extreme value of the pressure control range. In this embodiment, oxygen is used as the process gas, the oxygen flow rate is 1000 sccm, and the nitrogen flow rate is 0 sccm.

[0049] In this embodiment, there are two modes for pressure control, namely pressure control and swing valve position control. For the high-pressure in-situ degumming process with a large flow rate, if the vacuum gauge configured on the machine is relatively small, it is advisable to avoid choosing the pressure control mode as much as possible. For the execution conditions of in-situ degumming, due to the large amount of gas used, the pressure control ability of the vacuum gauge on the equipment is limited (for example, for some machine configurations, since the pressure during etching operation is 40 - 80 mt, in order to achieve high-precision pressure control, the vacuum gauge range is 0 - 100 mt, and only pressure control below 100 mt can be performed). In fact, both control modes can complete the surface treatment of the PAD, achieving the purpose of stripping the photoresist on the product surface, cleaning the working chamber, and improving the aluminum corrosion on the PAD surface.

[0050] If the pressure control mode is selected, due to the large amount of gas and the influence of the pumping speed of the molecular pump on the machine, a relatively high pressure control is required, and a relatively large pressure value within the pressure control range can be selected for setting. For example, if the pressure control range of the machine is 0 - 100 mt, then the pressure parameter settings of 80 - 95 mt can be selected; if the pressure control range of the machine is 0 - 500 mt, then the pressure parameter settings of 200 - 450 mt can be selected; if the pressure control range of the machine is 0 - 1 Torr, then the appropriate pressure parameters can be selected according to the gas flow rate, and the selection range is 300 - 900 mt.

[0051] For different machine models, the equipment hardware related to pressure such as the chamber size is different, and different condition configurations can be selected. However, the setting methods can all be carried out in the following two ways:

[0052] Method 1: In the manual state of the machine, set the gas type, flow rate, and swing valve position, and observe the pressure value displayed on the equipment. At this time, the pressure value can be used as a reference value for condition setting.

[0053] For example: The volume of the equipment chamber is 21400 cc, the model of the configured molecular pump is TS440 - C, the vacuum gauge range is 0 - 500 mt, the expected swing valve position during equipment operation is 30% - 70%, and the oxygen flow rate is 1000 sccm. Then the method for setting the pressure equipment parameters is as follows: Set the swing valve position to 70%, introduce 1000 sccm of oxygen. At this time, the first current pressure value displayed on the equipment is 220 mt, and we need to set the pressure above 220 mt.

[0054] Set the swing valve position to 30%, introduce 1000 sccm of oxygen. At this time, the second current pressure value displayed on the equipment is 360 mt, and we need to set the pressure below 360 mt.

[0055] Based on the comprehensive test results, the process pressure adjustment range is 220 - 360 mt. For example, the process pressure of 300 mt can be selected.

[0056] Method 2: Under the manual state of the machine, set the gas type, flow rate, and pressure value. Assume that the desired swing valve position is between 30% and 70%. Observe the position of the swing valve at this time. If the display is between 30% and 70%, it means that the equipment pressure control can meet the requirements and the gas flow rate does not need to change. If it is >70%, it indicates that the gas volume is too large and the pressure value setting is too small. For example, it can be verified by reducing the gas flow rate by 50 sccm each time and increasing the pressure by 10 mt until the swing valve position meets the range of 30% - 70%.

[0057] In addition, if the pressure control mode of the swing valve position is selected, it needs to be carried out according to the name definition of different swing valve positions for different machine types. For example, when the Ring_Mode parameter of some machines is set to 1, the pressure is not monitored, and when it is set to 2, the pressure monitoring takes effect, and only then the definition of the Press parameter is read by the machine. The pressure definition can be directly skipped by setting Ring Mode to 2. If the equipment has a parameter definition for the swing valve position, the swing valve position can also be fixed. The generally relatively stable position of the swing valve is between 5% and 97%. In this mode, the process parameters of this step can be set as follows: specify the swing valve position as 70%, select the process gas as O2, the flow rate as 1000 sccm, and the time is fixed at 5 s.

[0058] For the radio frequency part, on the machine that controls plasma generation in dual frequencies, the radio frequencies can be respectively called SourceRF, abbreviated as SRF (in some models, it is also called Top RF or Top power) and Bias RF, abbreviated as BRF (in some models, it is also called Bottom RF or bottom power). SRF is the component that generates plasma, and its setting range can be 500 - 1200 W. BRF can increase the ion energy and directionality, and will increase the ion bombardment on the product surface. Therefore, the acceptance ability of the product surface film layer to ion bombardment needs to be considered in the implementation of in-situ desmearing. If the passivation film on the product surface is sensitive to ion bombardment, the setting of BRF cannot be too high, generally set to 0 - 10 W. If the passivation film is not sensitive to oxygen ion bombardment, or only partial photoresist stripping is performed, a slightly higher BRF can be selected, with a range of 100 - 200 W. In this example, SRF is set to 600 W and BRF is set to 10 W.

[0059] Due to the difference in the thickness of the photoresist on the product surface after etching caused by different product designs, as well as the difference in the desmearing rate of different in-situ desmearings, the operation time can be selected from 20 to 100 s. For example, after the product is etched by PAD, the remaining thickness of the photoresist on the surface is 1 um. According to the foregoing parameters, the desmearing rate of the in-situ desmearing can be calculated as If about the photoresist on the surface needs to be stripped during the in-situ desmearing process, the process time is set to 45 s for partial photoresist stripping.

[0060] Example 2:

[0061] This embodiment provides another method for surface treatment after PAD etching. The difference from Example 1 is that before introducing process gas into the chamber, it further includes:

[0062] Discharging the residual gas inside the chamber by means of gas replacement. The gas used for gas replacement includes at least one of O2, N2, and He.

[0063] And, as Figure 2 shown, in this embodiment, all photoresists are directly stripped during in-situ resist stripping, and then wet cleaning is performed. Figure 3 is the product cross-sectional view before resist stripping in the embodiment of the present invention; Figure 4 is the product cross-sectional view after resist stripping in the embodiment of the present invention. It can be seen that before resist stripping, it includes photoresist 1, etch buffer layer 2 (for example, containing metals such as Ti and TiN), metal layer 3 (for example, Al), PAD film 4, and lower-layer product film 5. After in-situ resist stripping by this method, photoresist 1 is completely removed.

[0064] Example 3:

[0065] A semiconductor element, which is processed by the method of Example 1 during the manufacturing process.

[0066] Example 4:

[0067] A semiconductor element, which is processed by the method of Example 2 during the manufacturing process.

[0068] In this embodiment, due to the relatively large amount of gas used and the limited pressure control ability of the vacuum gauge on the equipment, in order to achieve high-precision pressure control, it is necessary to comprehensively adjust the swing valve position, gas flow rate, and process pressure to ensure the stability of the chamber state. Due to the existence of bias voltage, the polymer will be oxidized and decomposed and discharged during the resist stripping process, and the F-containing gas in the lattice gaps will also be replaced, greatly reducing the F content on the product surface. Without F ions on the surface as a catalyst, metallic aluminum will naturally oxidize to form a bright protective film of aluminum oxide, and aluminum corrosion will no longer occur. At the same time, the plasma has a certain bombardment property, and it can relatively easily remove the hard-to-remove hardened glue layer.

[0069] The substantial effects of this embodiment include:

[0070] After in-situ ashing, due to the existence of bias voltage, the polymer will be oxidized, decomposed and discharged during the ashing process. The F-containing gas in the lattice gaps will also be replaced by oxygen ions, and the F content on the product surface will be greatly reduced. After subsequent conventional dry ashing and wet cleaning, without F ions on the surface as a catalyst, metallic aluminum will naturally oxidize to form a bright protective film of aluminum oxide, and aluminum corrosion will no longer occur.

[0071] Using the product wafer itself for lower electrode protection, there is no need to additionally introduce a dummy wafer, which reduces the equipment handling time and the loss of the dummy wafer, and improves the equipment productivity. The etching process is at a conventional temperature, and the chamber temperature is not specifically required to be heated, which is beneficial to avoiding the problems of resist collapse and resist smearing caused by high chamber temperature; there is no need to increase the chamber area, which reduces the floor area occupied by the factory building, increases the equipment maintenance space, and reduces the maintenance difficulty. It ensures the cleanliness of the chamber environment, can effectively improve the equipment maintenance time, and improves the equipment productivity.

[0072] Since the frequency band of the etching chamber RF source is low and the oxygen plasma has a certain bombardment property, while the RF source of the asher is in the microwave frequency band, although the oxygen plasma concentration is high, its bombardment property is insufficient (a small bombardment property can ensure little damage to the product). Therefore, the oxygen plasma can relatively easily remove the hardened resist layer.

[0073] If partial ashing is adopted, after removing the hardened photoresist inside the etcher, the remaining photoresist is removed by a conventional asher, which can not only ensure that all the photoresist is removed cleanly, but also avoid damage to the surface dielectric film.

[0074] Through the description of the above embodiments, those skilled in the art can understand that for the convenience and simplicity of description, only the above division of each functional module is used as an example. In actual applications, the above functions can be allocated to different functional modules according to needs, that is, the internal structure of a specific device is divided into different functional modules to complete all or part of the functions described above.

[0075] In the embodiments provided in the present application, it should be understood that the disclosed structure and method can be implemented in other ways. For example, the embodiments of the structure described above are only illustrative. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another structure, or some features can be ignored or not executed. Another point, the displayed or discussed coupling or direct coupling or communication connection between each other can be through some interfaces, and the indirect coupling or communication connection of structures or units can be in electrical, mechanical or other forms.

[0076] The unit described as a separating component may or may not be physically separated. The component shown as a unit may be a single physical unit or multiple physical units, that is, it may be located in one place or distributed to multiple different places. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0077] In addition, each functional unit in the embodiments of this application can be integrated into a processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0078] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of the embodiments of this application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to enable a device (which can be a single-chip microcomputer, a chip, etc.) or a processor to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes: USB flash drives, mobile hard disks, read only memory (ROM), random access memory (RAM), magnetic disks, or optical discs and other various media that can store program codes.

[0079] The above content is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed in this application can easily think of changes or substitutions, which should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

1. A method for surface treatment after PAD etching, characterized in that A semiconductor device with an aluminum metal layer, comprising the following steps: Discharging the residual fluorine-containing gas inside the chamber by gas replacement; Introducing process gas into the chamber, and adjusting the remaining parameters according to one or two of the swing valve position, gas flow rate, and process pressure to maintain the stable state of the chamber; Performing ion bombardment for a preset duration at a preset radio frequency power to strip all or part of the photoresist. After the photoresist is stripped, wet cleaning is also included. During the process, the metal aluminum is naturally oxidized to form a protective film of aluminum oxide; The adjustment of the remaining parameters according to one or two of the swing valve position, gas flow rate, and process pressure includes: Determining the gas flow rate and swing valve position range, measuring the first current pressure according to the upper limit value of the swing valve position and the gas flow rate, measuring the second current pressure according to the lower limit value of the swing valve position and the gas flow rate, and determining the process pressure adjustment range with the first current pressure and the second current pressure as the upper and lower limits, and performing process pressure adjustment; Or, determining the swing valve position range, measuring the current swing valve position according to the current gas flow rate and current pressure, and adjusting the current gas flow rate and / or current pressure until the current swing valve position meets the swing valve position range; The process gas includes oxygen or a mixed gas. When the process gas is a mixed gas, the oxygen content in the mixed gas is not less than 50%.

2. A method for surface treatment after PAD etching according to claim 1, characterized in that, The swing valve position is selected from 30% to 70%, the gas flow rate is selected from 600 to 1200 sccm, and the process pressure is selected from 30% to 95% of the extreme value of the pressure control range.

3. A method for surface treatment after PAD etching according to claim 1, characterized in that, The ion bombardment at a preset radio frequency power for a preset duration includes: Determining the radio frequency power range according to the sensitivity of the PAD film to ion bombardment, selecting the preset radio frequency power from the radio frequency power range according to the photoresist thickness, the amount of photoresist removal, and the expected photoresist removal time, and performing ion bombardment with the expected photoresist removal time as the preset duration; Or, determining the radio frequency power according to the sensitivity of the PAD film to ion bombardment, calculating the preset duration according to the determined radio frequency power, the photoresist thickness, and the amount of photoresist removal, and performing ion bombardment.

4. A method for surface treatment after PAD etching according to claim 1 or 3, characterized in that, The value range of the preset radio frequency power includes 500 to 1200 W, and the value range of the preset duration includes 20 to 100 s.

5. A method for surface treatment after PAD etching according to claim 1, characterized in that, The gas used for gas replacement includes at least one of O2, N2, and He.

6. A method for surface treatment after PAD etching according to claim 1, characterized in that, After all the photoresist is stripped, wet cleaning is also included; after part of the photoresist is stripped, dry photoresist removal and wet cleaning are also included.

7. A semiconductor device, characterized in that, The semiconductor device is processed by the surface treatment method of a PAD etching described in any one of claims 1-6 during the manufacturing process.

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