Cavity stability control method under high hydrogen process and semiconductor equipment

Abstract

The embodiment of the application discloses a cavity stability control method under a high hydrogen process and a semiconductor device, and comprises the following steps: S11, providing a plasma processing cavity, a filter plate is arranged in the cavity, and the inner wall surface of the cavity and the surface of the filter plate are provided with an aluminum oxide layer; S12, performing activation treatment on the surface of the aluminum oxide layer; S13, reacting to form a first passivation layer with an Al-O-C-N three-dimensional network skeleton structure on the surface of the aluminum oxide layer; S14, completing a high hydrogen process with a preset processing number; S15, reacting to form a second passivation layer with an Al-O-C-N three-dimensional network skeleton structure on the basis of the first passivation layer; S16, repeatedly performing S14 to S15; and S17, when the total duration of the high hydrogen process meets a threshold value, performing S12 to S13 again. The application can effectively reduce the generation of particles, eliminate the etching rate drift of the high hydrogen process, and improve the cavity stability.

Description

Technical Field

[0001] This application relates to the field of semiconductor processing technology, and in particular to a method for controlling cavity stability and a semiconductor device under high-hydrogen processes. Background Technology

[0002] In some plasma processes using high hydrogen content (such as degumming or plasma surface treatment processes using a hydrogen-nitrogen mixture with a hydrogen flow rate greater than 4% as the base process gas, high-hydrogen processes), the surfaces of the cavity's metal components (e.g., aluminum alloy filter plates) and the cavity's inner walls (typically anodized aluminum and ceramic composite structures) are susceptible to damage from prolonged exposure to high concentrations of hydrogen particles. This damage leads to particle shedding, cavity contamination, and negatively impacts product electrical properties and yield. It also causes deviations in the cavity etching rate, thus affecting cavity stability under high-hydrogen processes and significantly shortening the cavity's lifespan. Therefore, it is necessary to research a control method that can significantly improve these problems. Summary of the Invention

[0003] The purpose of this application is to overcome the above-mentioned problems in the prior art and provide a cavity stability control method and semiconductor device under high hydrogen process, which can prevent the inner wall of the cavity from being damaged by hydrogen and causing particle shedding and contamination, so as to unify the etching impedance of the cavity surface, eliminate etching rate drift in high hydrogen process, and improve mass production stability.

[0004] To achieve the above objectives, the technical solution of this application is as follows: According to a first aspect of this application, an embodiment of this application provides a method for controlling the stability of a cavity in a high-hydrogen process, wherein the cavity is a plasma processing cavity, and a filter plate for filtering charged particles in the plasma is provided in the cavity. The inner wall surface of the cavity and the surface of the filter plate have an Al2O3 layer (alumina layer). The control method includes the following steps: (a) An oxidizing gas is introduced into the cavity and a continuous plasma mode is activated to perform the first activation treatment on the surface of the Al2O3 layer; (b) Introduce carbon-containing oxygen gas, nitrogen-containing hydrogen gas, and a first mixed gas of hydrogen and nitrogen into the cavity, and turn on the continuous plasma mode to react on the surface of the Al2O3 layer to form an interfacial composite anchoring layer containing Al-OC interface covalent anchoring bonds and Al-N interface covalent anchoring bonds. (c) Introduce carbon-oxygen gas and a second mixed gas of hydrogen and nitrogen into the cavity, and activate the periodic cyclic pulse plasma mode to react and form a first passivation layer with an Al-OCN three-dimensional mesh skeleton structure on the basis of the interface composite anchoring layer. (d) Introduce a third mixture of hydrogen and nitrogen into the cavity and activate the continuous plasma mode to complete the high-hydrogen process with a preset number of treatments; (e) Introduce carbon-oxygen gas and a fourth mixed gas of hydrogen and nitrogen into the cavity, and activate the periodic cyclic pulse plasma mode to react and form a second passivation layer with an Al-OCN three-dimensional mesh skeleton structure on the basis of the first passivation layer, so as to repair the damaged first passivation layer. Repeat steps (d) to (e), and when the total duration of the high-hydrogen process meets the threshold, repeat steps (a) to (c).

[0005] In some embodiments, the oxidizing gas includes O2.

[0006] In some embodiments, the carbon-containing oxygen gas includes CO.

[0007] In some embodiments, the nitrogen-containing hydrogen gas includes NH3.

[0008] In some embodiments, the hydrogen flow rate in the first mixed gas is less than 4%, and the nitrogen flow rate is more than 96%.

[0009] In some embodiments, the hydrogen flow rate in the second mixed gas, the third mixed gas, and the fourth mixed gas accounts for more than 4% to 40%, and the nitrogen flow rate accounts for less than 96% to 60%.

[0010] In some embodiments, when performing (a) to (e), the cavity temperature is 150°C to 500°C.

[0011] In some embodiments, when performing step (b), the flow rates of the nitrogen-containing hydrogen gas, the carbon-containing oxygen gas, and the first mixed gas increase sequentially.

[0012] In some embodiments, when performing (b), (c) and (e), the partial pressure of the carbon-oxygen gas is below 30 mTorr.

[0013] In some embodiments, after performing the first activation treatment in step (a), the method further includes: introducing argon gas into the cavity and activating a continuous plasma mode to perform a second activation treatment on the surface of the Al2O3 layer.

[0014] In some embodiments, after forming the first passivation layer, step (c) further includes: introducing a fifth mixed gas of hydrogen and nitrogen into the cavity and activating a continuous plasma mode to perform plasma annealing and bonding treatment on the first passivation layer.

[0015] In some embodiments, the hydrogen flow rate in the fifth mixed gas is less than 4%, and the nitrogen flow rate is more than 96%.

[0016] In some embodiments, after performing the plasma annealing and bonding process in step (c), the process further includes: introducing nitrogen gas into the cavity and turning off the plasma radio frequency to perform thermal relaxation and curing treatment on the first passivation layer.

[0017] In some embodiments, after forming the second passivation layer, step (e) further includes: introducing a sixth mixed gas of hydrogen and nitrogen into the cavity and activating a continuous plasma mode to perform surface passivation treatment on the second passivation layer.

[0018] In some embodiments, the hydrogen flow rate in the sixth mixed gas is less than 4%, and the nitrogen flow rate is more than 96%.

[0019] In some embodiments, in step (c), when the periodic cyclic pulse plasma mode is turned on, the number of cycles is 10 to 20, the radio frequency turn-on time in each cycle is 60 to 80 seconds, and the radio frequency turn-off time is 20 to 40 seconds.

[0020] In some embodiments, in step (e), when the periodic cyclic pulse plasma mode is activated, the number of cycles is 1 to 3, the radio frequency activation time in each cycle is 30s to 50s, and the radio frequency deactivation time is 10s to 30s.

[0021] In some embodiments, the preset number of processing times is 1 to 3 times (corresponding to high hydrogen process on 1 wafer to high hydrogen process on 3 consecutive wafers).

[0022] In some embodiments, the threshold is 500 hours to 1500 hours.

[0023] In some embodiments, the thickness of the first passivation layer is 10 nm to 300 nm.

[0024] According to a second aspect of this application, embodiments of this application also provide a semiconductor device including a cavity, the semiconductor device being used to perform a cavity stability control method under a high-hydrogen process as provided in any of the embodiments of the first aspect above.

[0025] The embodiments of this application may have, or at least have, the following advantages: (1) By first introducing carbon-oxygen gas, nitrogen-hydrogen gas, and a first mixed gas of hydrogen and nitrogen into the cavity, and activating the continuous plasma mode, the generated free radicals containing C, O, N, and H can react with the surface of the Al2O3 layer (amorphous network structure) on the inner wall of the cavity and the surface of the filter plate to generate two types of interfacial covalent anchoring bonds, Al-OC and Al-N, to disperse interfacial stress and significantly improve the adhesion between the formed interfacial composite anchoring layer film (seed layer) and the substrate. In particular, during the interfacial grafting stage, the addition of trace amounts of nitrogen-hydrogen gas can effectively improve the efficiency of N free radical generation by system dissociation, promote the simultaneous generation of Al-N interfacial bonds, realize a composite anchoring interface containing Al-OC and Al-N, multiply the anchor point density, and improve the bonding strength between the film and the alumina cavity substrate. Then, by introducing carbon-oxygen gas and a second mixture of hydrogen and nitrogen into the cavity and activating a periodic cyclic pulsed plasma mode, adsorption, film formation, and branching growth can be achieved using free radicals during the RF turn-on phase. During the RF turn-off relaxation phase, sufficient lateral cross-linking time is provided for the active free radicals, promoting intermolecular lateral cross-linking, pruning loose carbon branches, closing the nanopores inside the film, and connecting the loose branches into a continuous network. This not only repairs defects but also promotes the densification of the newly formed cross-linked structure, avoiding the local porosity problem caused by using a continuous plasma mode. This results in a dense first passivation layer (Al-OCN ternary hybrid polymer film) with a continuous Al-OCN three-dimensional network framework structure. Thus, the cavity can be pre-treated and maintained before the high-hydrogen process, achieving basic protection (pre-protection) for the filter plate surface and the inner wall of the cavity by forming the first passivation layer. Furthermore, during the high-hydrogen process, during intermittent periods, a fourth mixed gas consisting of carbon-oxygen gas and hydrogen and nitrogen can be introduced into the cavity, and a periodic cyclic pulsed plasma mode can be activated. The generated free radicals can then regraft and crosslink the CN / CO crosslinking sites that have been broken by H free radicals. This reaction forms a second passivation layer with an Al-OCN three-dimensional network framework structure on top of the first passivation layer. This allows for online regenerative compaction and repair of the first passivation layer, which has been damaged by continuous erosion from high-hydrogen free radicals during the high-hydrogen process, resulting in surface crosslinking breakage defects. This achieves a dynamic balance between "hydrogen erosion loss" and "crosslinking repair." Consequently, while effectively reducing particle generation and enabling online maintenance, it avoids fluctuations in the etching rate of the cavity, preventing impacts on the high-hydrogen process and thus improving the cavity stability under high-hydrogen conditions. Furthermore, by periodically inserting the execution (e) during the high-hydrogen process, a second passivation layer can be periodically formed on the surface of the filter plate and the inner wall of the cavity to renew and protect the cavity, avoiding the long-term effects of hydrogen and significantly extending the service life of the cavity components.By repeating steps (a) to (c) when the total duration of the high-hydrogen process meets the threshold, the film that has accumulated stress and aged after long-term operation can be removed, and a new dense passivation layer can be reconstructed, thus preventing the film from continuously thickening and peeling off to produce particles.

[0026] (2) By performing the first activation treatment, the surface of the Al2O3 layer can be slightly etched to increase the density of Al-OH hydroxyl sites, which can provide sufficient sites for the formation of Al-OC and Al-N composite anchoring bonds. By performing the second activation treatment, neutral argon particles and low-kinetic-energy argon ions can be used to gently act on the surface of the Al2O3 layer, breaking some Al-O chemical bonds on the surface of the alumina through energy transfer, generating high-density Al dangling bonds, which increases the density of surface active sites; and can optimize the density of surface hydroxyl (Al-OH) to reach the optimal range for grafting reaction with CO free radicals, which helps to simultaneously form Al-OC and Al-N composite anchoring bonds and enhances the interfacial bonding force of the first passivation layer.

[0027] (3) By introducing a fifth mixed gas of hydrogen and nitrogen into the cavity and activating the continuous plasma mode, the first passivation layer after formation is subjected to plasma annealing and bonding treatment. The nitrogen-hydrogen plasma with low hydrogen content can be used to eliminate unsaturated C and N dangling bonds inside the first passivation layer film and passivate the active sites inside the film. Further, by introducing nitrogen into the cavity and turning off the plasma radio frequency, the first passivation layer is subjected to thermal relaxation and curing treatment only in a high-temperature nitrogen environment. The slight rearrangement of the surface atoms of the film can be driven by heat to further close the micro-nano pores and stabilize the cross-linked network. By introducing a sixth mixed gas of hydrogen and nitrogen into the cavity and activating the continuous plasma mode, the second passivation layer after formation is subjected to surface passivation treatment. The nitrogen-hydrogen plasma with low hydrogen content can be used to passivate the free carbon sites on the surface of the film and suppress the risk of carbon agglomeration and precipitation.

[0028] (4) By strictly controlling the partial pressure of carbon-containing oxygen gas, the supply rate of C free radicals is lower than the cross-linking consumption rate of the passivation layer film, thereby controlling and suppressing the generation of free carbon particles through homogeneous nucleation in the gas phase, making the risk of pollution caused by the precipitation and shedding of free carbon controllable. The prepared dense passivation film can effectively block the inward penetration of hydrogen free radicals, suppress the release of Al and O impurities in the cavity, and significantly extend the long-term stable period of cavity passivation.

[0029] Other advantages of this application will be described in the following detailed description. Attached Figure Description

[0030] Figure 1 This is a flowchart of a cavity stability control method under a high-hydrogen process, provided as a preferred embodiment of this application.

[0031] Figure 2This is a schematic diagram of the cavity structure of a semiconductor device provided in a preferred embodiment of this application.

[0032] In the diagram: 10. Cavity; 11. Air inlet; 12. Filter plate; 13. Heating platform; 14. Exhaust port. Detailed Implementation

[0033] To address the issue that the surfaces of metal components (e.g., aluminum alloy filter plates) and the inner walls of the cavity (typically anodized aluminum and ceramic composite structures) are easily damaged by prolonged exposure to high concentrations of hydrogen particles during high-hydrogen processes, becoming a major source of particulate contamination and thus affecting the cavity stability under high-hydrogen conditions, this application provides a method for controlling cavity stability under high-hydrogen processes. The cavity is a plasma processing cavity, and a filter plate is installed within the cavity to filter charged particles from the plasma. The inner wall surface of the cavity and the filter plate surface have an Al2O3 layer. The control method includes the following steps: (a) An oxidizing gas is introduced into the cavity and a continuous plasma mode is activated to perform the first activation treatment on the surface of the Al2O3 layer; (b) Introduce carbon-containing oxygen gas, nitrogen-containing hydrogen gas, and a first mixed gas of hydrogen and nitrogen into the cavity, and turn on the continuous plasma mode to react on the surface of the Al2O3 layer to form an interfacial composite anchoring layer containing Al-OC interface covalent anchoring bonds and Al-N interface covalent anchoring bonds. (c) Introduce carbon-oxygen gas and a second mixed gas of hydrogen and nitrogen into the cavity, and activate the periodic cyclic pulse plasma mode to react and form a first passivation layer with an Al-OCN three-dimensional mesh skeleton structure on the basis of the interface composite anchoring layer. (d) Introduce a third mixture of hydrogen and nitrogen into the cavity and activate the continuous plasma mode to complete the high-hydrogen process with a preset number of treatments; (e) Introduce carbon-oxygen gas and a fourth mixed gas of hydrogen and nitrogen into the cavity, and activate the periodic cyclic pulse plasma mode to react and form a second passivation layer with an Al-OCN three-dimensional mesh skeleton structure on the basis of the first passivation layer, so as to repair the damaged first passivation layer. Repeat steps (d) to (e), and when the total duration of the high-hydrogen process meets the threshold, repeat steps (a) to (c).

[0034] This application embodiment achieves pre-protection of the filter plate surface and cavity inner wall (Al2O3 layer) by forming a first passivation layer on the filter plate surface and cavity inner wall. During the high-hydrogen process, a second passivation layer is formed on the filter plate surface and cavity inner wall, and the damaged first passivation layer is repaired online through regenerative compaction. This allows for online maintenance while avoiding fluctuations in the high-hydrogen process. This application embodiment avoids hydrogen damage based on the particle formation mechanism, mitigating it at the source of particle generation and establishing a new high-hydrogen process flow. This unifies the etching resistance of the cavity surface, effectively preventing prolonged hydrogen exposure and eliminating etching rate drift in the high-hydrogen process, thereby improving mass production stability and extending the service life of cavity components.

[0035] This application also provides a semiconductor device, including a cavity, which is used to perform the cavity stability control method described above under a high-hydrogen process.

[0036] The specific embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0037] refer to Figure 1 In a first aspect, a cavity stability control method under a high-hydrogen process according to an embodiment of this application may sequentially include the following steps: Step S11: Provide a plasma processing chamber, in which a filter plate is provided, and the inner wall surface of the chamber and the surface of the filter plate have an Al2O3 layer.

[0038] refer to Figure 2 In some embodiments, the control method of this application is used to control the stability of a cavity under a high-hydrogen process. The cavity 10 is a plasma processing cavity used to perform a high-hydrogen process, such as a plasma stripping process or a plasma surface treatment process using a high hydrogen content (hydrogen flow rate in the mixed gas with nitrogen is greater than 4%). The cavity 10 is disposed on a semiconductor device, which is a plasma processing device.

[0039] In some embodiments, the cavity 10 includes a heating stage 13 and metal components such as an ion filter. The ion filter includes a filter plate 12 for filtering charged particles in the plasma, with multiple ion filter holes densely distributed on the filter plate 12. The inner wall surface of the cavity 10 and the surface of the filter plate 12 have an Al2O3 layer (the filter plate 12 is made of aluminum alloy with an Al2O3 layer on its surface (either native or anodized), and the inner wall of the cavity is a composite structure of anodized aluminum and ceramic). The filter plate 12 is horizontally positioned in the cavity 10, above the heating stage 13. The filter plate 12 divides the cavity 10 into two relatively independent upper and lower parts, including an upper cavity above the filter plate 12 and a lower cavity below the filter plate 12, which together constitute the cavity 10. The heating stage 13 is located in the lower cavity and is used to place the production wafers (product wafers) that need to be processed in the high-hydrogen process, and to maintain the process temperature during processing through heating and temperature control. An air inlet 11 is provided at the top of the cavity 10 (upper cavity). The air inlet 11 is used to introduce an excitation gas (a rare gas, such as one or more inert gases like He, Ne, Ar, Kr, etc.) and a process gas used in the high-hydrogen process (including a mixture of H2 and N2). The process gas entering the upper cavity can be excited by the excitation gas to form plasma in the upper cavity. When it passes through the filter plate 12 and enters the lower cavity, the charged particles in it are filtered out by the filter plate 12 before it is used to process the production wafers placed on the hot stage 13. The air inlet 11 is also used to introduce reactive gases (such as oxidizing gases, carbon-oxygen gases, nitrogen-hydrogen gases, etc. used in the control method of this application embodiment). The reactive gases are excited by the excitation gas to form plasma, which is used to perform the different treatments described below on the inner wall of the cavity 10 and the surface of the filter plate 12. An exhaust port 14 is provided at the bottom of the cavity 10 (lower cavity) for discharging waste gas and controlling the cavity pressure.

[0040] In some embodiments, when the control method of this application is executed, the cavity temperature is 150°C to 500°C (high temperature environment).

[0041] Step S12: Activate the surface of the Al2O3 layer.

[0042] When the cavity 10 is used for the first time (including the first use of a new cavity and the first use of a cavity after regular maintenance (cavity opening maintenance, replacement of liner / seals, excessive particle content, periodic aging membrane removal and reconstruction), the warm-up time before the high-hydrogen process can be used to perform pre-treatment maintenance on the cavity 10 in its first-use state. The purpose is to pre-coat a passivation layer (first passivation layer) on the surface of the filter plate 12 and the inner wall surface of the cavity 10 (including the upper cavity and lower cavity) (i.e., the surface of the Al2O3 layer), thus pre-protecting the surface of the filter plate 12 and the inner wall surface of the cavity 10. To achieve this, the surface of the Al2O3 layer on the filter plate 12 and the inner wall of the cavity 10 can first be activated to facilitate the formation of the passivation layer.

[0043] refer to Figure 2 In some embodiments, an oxidizing gas can be introduced into the cavity 10 through the air inlet 11, and a continuous plasma mode (radio frequency is continuously on) can be activated. The excited gas in the upper cavity will generate an oxygen-containing plasma. The oxygen free radicals in the oxygen-containing plasma will be used to perform a first activation treatment on the surface of the Al2O3 layer, so as to perform high-temperature (150°C~500°C) oxygen plasma cleaning on the inner wall of the cavity and the surface of the filter plate, oxidizing and decomposing organic contaminants such as glove grease, fingerprints, and assembly lubricating oil, and activating the surface of the Al2O3 layer on the inner wall of the cavity and the surface of the filter plate. Through the slight etching effect on the surface of the Al2O3 layer, the density of Al-OH hydroxyl sites on the surface is increased, providing sufficient sites for the subsequent formation of Al-OC and Al-N composite anchoring bonds.

[0044] In some embodiments, the oxidizing gas may include O2, etc.

[0045] In some embodiments, during the first activation treatment, the flow rate of the oxidizing gas (O2) is 100 SCCM to 2000 SCCM, the chamber pressure is 100 mTorr to 1000 mTorr, the source power is 100 W to 2000 W, the bias power is 0 W to 200 W, and the time is 5 min to 30 min.

[0046] In some embodiments, after the first activation treatment, the introduction of oxidizing gas is stopped, and a purge gas is introduced to purge the interior of the chamber at a high temperature (the same temperature as above, the same below). The purge gas can be a non-reactive gas such as N2. By continuously purging with high-purity N2, residual O2, water vapor, and oxidation gaseous byproducts in the chamber are thoroughly removed, preventing the CO used in the next stage from being consumed by residual oxygen.

[0047] In some embodiments, during the high-temperature purging transition, the flow rate of the purging gas (N2) is 500 SCCM to 1000 SCCM, the cavity pressure is 100 mTorr to 500 mTorr, the radio frequency is turned off, and the time is 5 min to 10 min.

[0048] In some embodiments, after a high-temperature purging transition, the purging gas flow is stopped, and high-purity argon (Ar) is introduced into the cavity while a continuous plasma mode is activated to establish a stable pressure, performing a second activation treatment on the Al2O3 layer surface. Here, argon neutral particles and low-kinetic-energy argon ions generated by the excited argon gas gently act on the Al2O3 layer surface, physically stripping weakly adsorbed oxidation byproducts from the cavity wall. Through energy transfer from the argon particles, some Al-O chemical bonds on the alumina surface are broken, generating high-density Al dangling bond active sites, thus increasing the surface active site density (without deep etching, only modifying the 1nm-2nm film thickness of the Al2O3 layer surface). Furthermore, the second activation treatment removes loose oxide fragments and weakly adsorbed carbon and oxygen byproducts remaining on the inner wall after the first activation treatment, eliminates the loose impurity layer at the interface, and optimizes the surface hydroxyl (Al-OH) density to achieve the optimal range for grafting reactions with CO free radicals, facilitating the subsequent simultaneous formation of Al-OC and Al-N composite anchoring bonds and enhancing the interfacial bonding force of the formed first passivation layer. After the second activation treatment is completed, the radio frequency is cut off, and Ar is introduced for a short period of purging. Then, high-purity N2 can be introduced for purging to remove excited-state particles and avoid residual Ar. + It continues to affect subsequent grafting reactions.

[0049] In some embodiments, during the second activation process, the argon flow rate is 100 SCCM to 1000 SCCM, the chamber pressure is 100 mTorr to 500 mTorr, the source power is below 200 W, the bias power is 0 W, and the time is 3 min to 6 min.

[0050] In some embodiments, during activation processing (first activation processing / second activation processing), a co-wafer (non-product wafer) may be placed on the hot stage 13 to protect the surface of the hot stage 13.

[0051] Step S13: A first passivation layer with an Al-OCN three-dimensional network framework structure is formed on the surface of the Al2O3 layer by reaction.

[0052] After the above activation treatment is performed on the cavity 10 used for the first time, passivation pre-protection treatment can be carried out on the surface of the filter plate 12 and the inner wall of the cavity 10.

[0053] In some embodiments, after activation treatment, the process is switched to introducing a first mixed gas of hydrogen and nitrogen, as well as a carbon-oxygen gas and a nitrogen-hydrogen gas, and a continuous plasma mode is activated. The plasma formed by exciting the carbon-oxygen gas, the nitrogen-hydrogen gas, and the first mixed gas is used to treat the surface of the filter plate 12 and the inner wall of the cavity 10. An interface composite anchoring layer containing Al-OC interface covalent anchoring bonds and Al-N interface covalent anchoring bonds is formed on the surface of the filter plate 12 and the inner wall of the cavity 10, i.e. on the surface of the Al2O3 layer.

[0054] By introducing a small amount of carbon-oxygen gas, a trace amount of nitrogen-hydrogen gas, and a first mixed gas of hydrogen and nitrogen into the cavity, and activating the continuous plasma mode, free radicals containing C, O, N, and H generated by exciting the carbon-oxygen gas, nitrogen-hydrogen gas, and the first mixed gas can react with the surface of the Al2O3 layer (amorphous network structure) on the inner wall of the cavity and the surface of the filter plate to generate two types of interfacial covalent anchoring bonds, Al-OC and Al-N, to disperse interfacial stress and significantly improve the adhesion between the formed interfacial composite anchoring layer film (seed layer) and the substrate. In the interface grafting stage, the addition of trace amounts of nitrogen-containing hydrogen gas effectively improves the efficiency of N radical generation from the system's dissociation, promoting the simultaneous formation of Al-N interfacial bonds and achieving a composite anchoring interface containing Al-OC and Al-N. This significantly increases the anchor point density and enhances the bonding strength between the film and the alumina cavity substrate. (If only carbon-containing oxygen gas is used to generate C radicals to form Al-OC anchoring bonds, the anchor point density is insufficient. Furthermore, the N radicals generated by N2 in the first mixed gas are inefficient. Therefore, adding a small amount of NH3 increases the efficiency and quantity of dissociated N radicals, enabling the simultaneous formation of Al-N interfacial bonds and achieving a composite anchoring interface of Al-OC and Al-N, thus increasing the anchor point density. The use of dual-type interface (Al-OC and Al-N) covalent bonds disperses stress, significantly improving the adhesion of the composite anchoring layer film to the alumina substrate, reducing the likelihood of localized peeling and detachment, and enhancing protective performance.) Simultaneously, by controlling the addition of a very small amount of nitrogen-containing hydrogen gas, the reduction damage to the Al-O framework on the substrate can be prevented.

[0055] In some embodiments, the carbon-containing oxygen gas includes CO, etc.

[0056] In some embodiments, the nitrogen-containing hydrogen gas includes NH3, etc.

[0057] In some embodiments, the hydrogen flow rate in the first mixed gas of hydrogen and nitrogen is less than 4%, and the nitrogen flow rate is more than 96%, with the sum of the hydrogen flow rate and nitrogen flow rate being 100% (the first to sixth mixed gases are all composed of hydrogen and nitrogen). For example, the hydrogen flow rate in the first mixed gas is 4%, and the nitrogen flow rate is 96%.

[0058] In some embodiments, when forming the interface composite anchoring layer, the flow rates of the introduced nitrogen-containing hydrogen gas (NH3), carbon-containing oxygen gas (CO), and the first mixed gas increase sequentially.

[0059] In some embodiments, when forming the interface composite anchoring layer, the flow rate of carbon dioxide (CO) gas is 50 SCCM to 100 SCCM, for example, the flow rate of carbon dioxide (CO) gas can be 80 SCCM; the flow rate of nitrogen-hydrogen gas (NH3) gas is 20 SCCM to 30 SCCM, for example, the flow rate of nitrogen-hydrogen gas (NH3) gas can be 25 SCCM; the flow rate of the first mixed gas is 200 SCCM to 400 SCCM, for example, the flow rate of the first mixed gas can be 320 SCCM. The chamber pressure is 100 mTorr to 300 mTorr, the source power is 100 W to 300 W, the bias power is 0 W, and the time is 5 min to 15 min.

[0060] In some embodiments, when carbon-oxygen gas (CO), nitrogen-hydrogen gas (NH3), and a first mixed gas are introduced, the partial pressure of the carbon-oxygen gas (CO) is below 30 mTorr (partial pressure calculation formula: P(CO) = P(total) × (CO flow rate / total inlet flow rate), where P(CO) is the partial pressure of CO, and P(total) is the chamber pressure). For example, the partial pressure of the carbon-oxygen gas (CO) can be approximately 17.1 mTorr. By strictly controlling the partial pressure of the carbon-oxygen gas (CO), the supply rate of C free radicals is kept lower than the crosslinking consumption rate of the passivation layer film, controlling and suppressing the generation of free carbon particles through homogeneous nucleation in the gas phase, making the risk of pollution caused by the precipitation and shedding of free carbon controllable. The flow rate of the carbon-oxygen gas (CO) can be linked to the chamber pressure servo system. When the total chamber pressure rises, the flow rate of the carbon-oxygen gas (CO) is automatically reduced proportionally to maintain the partial pressure of the carbon-oxygen gas (CO) stable at ≤30 mTorr.

[0061] In some embodiments, after forming the interface composite anchoring layer, the process switches to introducing a second mixed gas of hydrogen and nitrogen, as well as a carbon-oxygen gas, and activates a periodic cyclic pulsed plasma mode (periodically turning the radio frequency power (mainly the source power) on and off in a pulsed manner). The plasma formed by the pulsed excitation of the carbon-oxygen gas and the second mixed gas is used to further treat the surface of the filter plate 12 and the inner wall of the cavity 10. Based on the already formed interface composite anchoring layer, a first passivation layer with an Al-OCN three-dimensional mesh framework structure is formed. The first passivation layer includes the interface composite anchoring layer.

[0062] By introducing carbon-oxygen gas and a second mixture of hydrogen and nitrogen into the cavity, and activating a periodic cyclic pulsed plasma mode, during the RF on-phase, free radicals in the plasma can be used for adsorption, film formation, and branching growth on the filter plate surface and the inner wall of the cavity. During the RF off-phase relaxation phase, no new free radicals continuously enter, allowing sufficient time for the active free radicals adsorbed on the film surface to undergo intermolecular lateral cross-linking, closing the nanopores inside the film and connecting the loose carbon branches into a continuous network (in continuous plasma mode, a continuous stream of new free radicals generates a large number of branches, and new layers are superimposed before cross-linking can occur, forming a large number of pores inside; pulsed mode can significantly reduce the porosity of the film). During the relaxation phase, H free radicals continue to act, trimming the excessively long loose carbon branches, reducing the free volume inside the film, and further densifying the film.

[0063] When the radio frequency is turned off, the high-energy plasma is rapidly submerged, but the adsorbed free radicals can still act on the surface. Compared to the non-pulsed method (referring to the continuous plasma method), this eliminates the need for continuous bombardment of the film surface, allowing for surface treatment with less damage. Utilizing the pulse relaxation window, defects can be repaired while simultaneously promoting the densification of the newly formed cross-linked structure. This avoids the localized porosity problem caused by the continuous plasma mode, forming a dense first passivation layer (Al-OCN ternary hybrid polymer film) with a continuous Al-OCN three-dimensional network framework on the basis of the interfacial composite anchoring layer. This allows for pre-treatment and maintenance of the cavity before the high-hydrogen process, achieving basic protection (pre-protection) of the filter plate surface and the cavity inner wall by forming the first passivation layer.

[0064] Because the interface composite anchoring layer contains high-density Al-OC and Al-N dual interface anchor points, it plays a good role as a seed layer for film formation. Therefore, when forming the first passivation layer, it is not necessary to add nitrogen-containing hydrogen gas (NH3) to the gas introduced.

[0065] In some embodiments, the hydrogen flow rate in the second gas mixture is greater than 4% to 40%, and the nitrogen flow rate is less than 96% to 60%. For example, the hydrogen flow rate in the second gas mixture is 20%, and the nitrogen flow rate is 80%.

[0066] In some embodiments, when forming the first passivation layer, the flow rate of the carbon oxide gas (CO) is 50 SCCM to 100 SCCM, for example, the flow rate of the carbon oxide gas (CO) may be 80 SCCM; the flow rate of the second mixed gas is 200 SCCM to 400 SCCM, for example, the flow rate of the second mixed gas may be 360 ​​SCCM. The cavity pressure is 100 mTorr to 300 mTorr, the source power is 100 W to 300 W, and the bias power is 0 W.

[0067] In some embodiments, when carbon-containing oxygen gas (CO) and a second mixed gas are introduced, the partial pressure of the carbon-containing oxygen gas (CO) is below 30 mTorr.

[0068] In some embodiments, when the first passivation layer is formed and the periodic cyclic pulsed plasma mode is activated, the number of cycles (each on-off cycle of the radio frequency is considered one cycle) is 10 to 20, the radio frequency on-time in each cycle is 60 to 80 seconds, and the radio frequency off-time is 20 to 40 seconds. For example, the radio frequency on-time in each cycle can be 70 seconds (source power is 220W), and the radio frequency off-time can be 30 seconds (source power is 0W), with 14 consecutive cycles, for a total duration of 23 minutes and 20 seconds.

[0069] In some embodiments, the thickness of the first passivation layer is 10 nm to 300 nm.

[0070] In some embodiments, after the first passivation layer is formed, a fifth mixed gas of hydrogen and nitrogen can be introduced into the cavity, and a continuous plasma mode can be activated to perform plasma annealing and bonding treatment on the formed first passivation layer.

[0071] In some embodiments, the hydrogen flow rate in the fifth gas mixture is less than 4%, and the nitrogen flow rate is more than 96%. For example, the hydrogen flow rate in the fifth gas mixture is 4%, and the nitrogen flow rate is 96%.

[0072] By introducing a fifth mixed gas of hydrogen and nitrogen into the cavity and activating the continuous plasma mode, the plasma formed by exciting the fifth mixed gas is used to perform plasma annealing and bonding treatment on the surface of the first passivation layer. The nitrogen-hydrogen plasma with low hydrogen content can be used to remove weakly adsorbed small molecule hydrocarbon fragments inside the first passivation layer film, eliminate unsaturated C and N dangling bonds inside the film, and passivate the active sites inside the film.

[0073] In some embodiments, during plasma annealing and bonding treatment, the flow rate of the fifth mixed gas is 200 SCCM to 500 SCCM, for example, the flow rate of the fifth mixed gas can be 400 SCCM. The chamber pressure is 100 mTorr to 300 mTorr, the source power is 100 W to 300 W, the bias power is 0 W, and the time is 5 min to 15 min.

[0074] In some embodiments, after plasma annealing and bonding treatment, nitrogen gas can be further introduced into the cavity, and the plasma radio frequency can be turned off to perform thermal relaxation and curing treatment on the first passivation layer.

[0075] By introducing high-purity nitrogen (N2) into the cavity after plasma annealing and bonding treatment, and turning off the plasma radio frequency (no plasma bombardment to avoid damaging the newly formed polymer network), the first passivation layer is thermally relaxed and cured only in a high-temperature nitrogen environment. The thermally driven atoms on the surface of the film can be slightly rearranged to further close the micro-nano pores and stabilize the cross-linked network, thereby making the density of the first passivation layer higher.

[0076] In some embodiments, during thermal relaxation curing, the nitrogen flow rate is 300 SCCM to 600 SCCM, for example, the nitrogen flow rate can be 500 SCCM. The chamber pressure is 100 mTorr to 500 mTorr, the source power and bias power are both 0 W, and the time is 3 min to 15 min.

[0077] In some embodiments, when performing the above process in step S13, a protective pad may be placed on the heating stage 13, and after the above process is completed, the protective pad is removed from the cavity 10.

[0078] In some embodiments, after thermal relaxation and curing, nitrogen gas can be introduced for final vacuum purging. Continuous nitrogen purging thoroughly removes free carbon radicals and gaseous byproducts from the chamber 10. After purging, the chamber 10 is in a vacuum standby state to facilitate the high-hydrogen process, processing the production wafers introduced into the chamber 10 and placed on the hot stage 13.

[0079] In some embodiments, during the final vacuum purging, the nitrogen flow rate is 500 SCCM to 1000 SCCM, for example, the nitrogen flow rate can be 500 SCCM. The chamber pressure is 100 mTorr to 500 mTorr, the source power and bias power are both 0 W, and the time is 3 min to 15 min.

[0080] Step S14: Complete the high-hydrogen process with a preset number of treatments.

[0081] In some embodiments, after a first passivation layer is formed on the surface of the filter plate and the inner wall of the cavity, and the cavity 10 is in a vacuum standby state, the high-hydrogen process can be started. During the high-hydrogen process, the production wafer is introduced into the cavity 10, placed on the hot stage 13, and a third mixture of hydrogen and nitrogen, used as the process gas for the high-hydrogen process, is introduced into the cavity 10. A continuous plasma mode is activated, and the surface of the production wafer is treated using the hydrogen- and nitrogen-containing plasma generated by exciting the third mixture. After treatment, the production wafer is sent out of the cavity 10. The high-hydrogen process can be completed a preset number of times in the manner described above (when processing multiple production wafers, after the current production wafer has been processed, it is sent out of the cavity 10, and then the next production wafer is introduced to continue processing until the set number (corresponding to the preset number of processing times) of production wafers has been processed).

[0082] In some embodiments, the hydrogen flow rate in the third gas mixture is greater than 4% to 40%, and the nitrogen flow rate is less than 96% to 60%. For example, in a typical high-hydrogen process, the hydrogen flow rate in the third gas mixture can be 20%, and the nitrogen flow rate can be 80%; in an even higher-hydrogen process, the hydrogen flow rate in the third gas mixture can reach 40%, and the nitrogen flow rate can be 60%. The high-hydrogen process can be understood with reference to existing technologies.

[0083] In some embodiments, the preset number of processing times is 1 to 3 times. That is, 1 to 3 production wafers are continuously processed based on the high-hydrogen process. For example, the preset number of processing times can be 1 time, that is, 1 production wafer is processed based on the high-hydrogen process each time.

[0084] Step S15: A second passivation layer with an Al-OCN three-dimensional mesh framework structure is formed on the basis of the first passivation layer.

[0085] In some embodiments, after a high-hydrogen process has been completed a preset number of times, for example, after a high-hydrogen process has been performed on one production wafer and before the next production wafer is loaded, a process is inserted to form a second passivation layer on the existing first passivation layer.

[0086] In some embodiments, an atmosphere stabilization pre-equilibrium process can be performed before forming the second passivation layer. In this process, according to the temperature, pressure, and other requirements for forming the second passivation layer, a fourth mixed gas of hydrogen and nitrogen at equal flow rates is introduced, and the plasma radio frequency is turned off to establish a stable basic gas phase environment and eliminate partial pressure fluctuations caused by airflow disturbances. This process takes 20 to 40 seconds, for example, 30 seconds. After the cavity pressure and gas partial pressure stabilize, the process of forming the second passivation layer (passivation defect repair process) can proceed.

[0087] In some embodiments, during the process of forming the second passivation layer, a fourth mixed gas of hydrogen and nitrogen is continuously introduced into the cavity, and a carbon-oxygen gas is also introduced. A periodic cyclic pulsed plasma mode is activated, and the plasma formed by the pulsed excitation of the carbon-oxygen gas and the fourth mixed gas is used to treat the surface of the filter plate and the inner wall of the cavity. Based on the already formed first passivation layer, a second passivation layer with an Al-OCN three-dimensional mesh framework structure is further formed to repair the damaged first passivation layer. NH3 may not be added in this process to simplify mass production control.

[0088] By introducing carbon-oxygen gas and a fourth mixture of hydrogen and nitrogen into the cavity, and activating a periodic cyclic pulsed plasma mode, the generated free radicals can be used to regraft and crosslink the CN / CO crosslinking sites that were broken by H free radicals during the high-hydrogen process. This reacts on the damaged first passivation layer to form a second passivation layer with the same Al-OCN three-dimensional network framework structure. This allows for online regenerative compaction repair of the first passivation layer damaged by continuous erosion from high-hydrogen free radicals during the high-hydrogen process, resulting in surface crosslinking breakage defects. This achieves a dynamic balance between "hydrogen erosion loss" and "crosslinking repair." Consequently, it effectively reduces particle generation, enables online maintenance, avoids fluctuations in the cavity's etching rate, prevents fluctuations in the high-hydrogen process, and improves the cavity's stability under high-hydrogen conditions.

[0089] In some embodiments, the hydrogen flow rate in the fourth gas mixture is greater than 4% to 40%, and the nitrogen flow rate is less than 96% to 60%. For example, the hydrogen flow rate in the fourth gas mixture is 20%, and the nitrogen flow rate is 80%.

[0090] In some embodiments, when forming the second passivation layer, the flow rate of the carbon oxide gas (CO) is 20 SCCM to 60 SCCM, for example, the flow rate of the carbon oxide gas (CO) can be 35 SCCM; the flow rate of the fourth mixed gas is 200 SCCM to 400 SCCM, for example, the flow rate of the fourth mixed gas can be 300 SCCM. The chamber pressure is 100 mTorr to 500 mTorr, the source power is 100 W to 300 W, and the bias power is 0 W.

[0091] In some embodiments, when carbon-oxygen gas (CO) and a fourth mixed gas are introduced, the partial pressure of the carbon-oxygen gas (CO) is below 30 mTorr. For example, the partial pressure of the carbon-oxygen gas (CO) may be approximately 18.8 mTorr.

[0092] In some embodiments, when forming the second passivation layer and activating the periodic cyclic pulsed plasma mode, the number of cycles is 1 to 3, with the radio frequency (RF) on-time in each cycle being 30 to 50 seconds and the RF off-time being 10 to 30 seconds. For example, the RF on-time in each cycle can be 40 seconds (source power of 170W), and the RF off-time can be 20 seconds (source power of 0W), with two consecutive cycles for a total duration of 120 seconds. Since the purpose of forming the second passivation layer is to repair the damaged first passivation layer, extending the number of cycles should be avoided, and a low-dose pulsed repair method should be used to repair only the surface damage of the thin film to prevent the film from continuously accumulating and thickening excessively.

[0093] In some embodiments, after the second passivation layer is formed, a sixth mixed gas of hydrogen and nitrogen can be introduced into the cavity, and a continuous plasma mode can be activated to perform surface passivation treatment on the second passivation layer.

[0094] In some embodiments, the hydrogen flow rate in the sixth gas mixture is less than 4%, and the nitrogen flow rate is more than 96%. For example, the hydrogen flow rate in the sixth gas mixture may be 4%, and the nitrogen flow rate may be 96%.

[0095] By introducing a sixth mixed gas of hydrogen and nitrogen into the cavity and activating the continuous plasma mode, the formed second passivation layer is subjected to plasma surface passivation finishing treatment. The nitrogen-hydrogen plasma with low hydrogen content can be used to remove weakly adsorbed carbon free radicals on the film surface, passivate free carbon sites on the film surface, and suppress the risk of carbon agglomeration and precipitation.

[0096] In some embodiments, during surface passivation, the flow rate of the sixth mixed gas is 200 SCCM to 400 SCCM, for example, the flow rate of the sixth mixed gas can be 360 ​​SCCM. The chamber pressure is 100 mTorr to 500 mTorr, the source power is 100 W to 500 W, the bias power is 0 W, and the time is 20 s to 60 s.

[0097] Step S16: Repeat steps S14 to S15.

[0098] In some embodiments, as the high-hydrogen process continues, steps S14 to S15 can be repeated, that is, the steps of completing the high-hydrogen process a preset number of times and forming the second passivation layer can be repeated. Thus, during the high-hydrogen process, a second passivation layer formation process can be inserted during the interval between every two production wafers to periodically form the second passivation layer on the filter plate surface and the inner wall of the cavity. This repairs the first passivation layer damaged after each high-hydrogen process, continuously updating and protecting the cavity, avoiding the long-term effects of hydrogen, and significantly extending the service life of the cavity components.

[0099] Step S17: When the total time of the high-hydrogen process meets the threshold, execute steps S12 to S13 again.

[0100] In some embodiments, as the total operating time of the high-hydrogen process increases, in order to ensure that the cavity stability requirements are met, when the total duration of the high-hydrogen process meets the threshold, the machine can be forcibly stopped and steps S12 to S13 can be executed again. That is, the activation treatment step for the Al2O3 layer surface and the step of forming the first passivation layer on the activated surface of the Al2O3 layer are executed again to remove the film that has accumulated stress and aged and damaged after long-term operation, and rebuild a new dense passivation layer to avoid the film from continuously thickening and peeling off to generate particles.

[0101] In some embodiments, the threshold can be 500 hours to 1500 hours, and can be adjusted according to actual operating conditions.

[0102] This application employs a pulsed plasma polymerization process (periodic cyclic pulsed plasma mode) to prepare a dense Al-OCN ternary hybrid network polymer passivation film (first passivation layer, second passivation layer). During the interface grafting stage, a trace amount of NH3 is introduced to simultaneously form Al-OC and Al-N composite interface anchoring bonds, enhancing the bonding strength between the film and the alumina cavity and filter substrate. In the pulsed plasma mode stage, a radio frequency shutdown relaxation window is utilized to provide sufficient lateral cross-linking time for active free radicals, significantly reducing the internal nanoporosity of the film and constructing a highly dense, continuous three-dimensional network framework. After film formation, a staged annealing and pure nitrogen thermal relaxation process is added to close the film's micropores and eliminate unsaturated dangling bonds. During the large-scale execution of the high-hydrogen process, a pulsed online regeneration and compaction process is used between production wafers to dynamically repair the cross-linking fracture defects on the passivation layer surface caused by continuous erosion from free radicals with a 20% hydrogen content (in extreme cases, 40% H2), achieving a dynamic balance between film loss and repair. The entire control method and process strictly constrains the partial pressure of CO precursor through multiple means, keeping the risk of free carbon precipitation at an extremely low level. The prepared dense passivation film can effectively block the inward penetration of hydrogen free radicals, inhibit the release of Al and O impurities in the cavity, and significantly extend the long-term stability period of cavity passivation.

[0103] In a second aspect, an embodiment of this application provides a semiconductor device including a cavity, the semiconductor device being used to perform a cavity stability control method under a high-hydrogen process as provided in any of the embodiments of the first aspect above.

[0104] refer to Figure 2 In some embodiments, the semiconductor device includes a plasma processing device, wherein the cavity 10 provided in the semiconductor device is a plasma processing cavity and can be used to perform high-hydrogen process processes, such as plasma resist removal processes or plasma surface treatment processes using a high hydrogen content (the flow rate of hydrogen in the mixed gas with nitrogen is more than 4%).

[0105] In some embodiments, a hot stage 13 is provided at the bottom of the cavity 10 for placing production wafers (production wafers) to be processed in the high-hydrogen process. The process temperature during processing can be maintained by heating and temperature control devices provided on the hot stage 13. An ion filter device is provided above the hot stage 13. The ion filter device has a filter plate 12 for filtering charged particles in the plasma. The filter plate 12 is densely covered with multiple ion filter holes. The filter plate 12 can filter charged particles passing through the ion filter holes by grounding, while allowing neutral free radicals to pass through. The filter plate 12 divides the cavity 10 into a relatively independent upper cavity and a lower cavity. An air inlet 11 is provided at the top of the cavity 10 (upper cavity) for introducing excitation gas (rare gas, such as one or more inert gases such as He, Ne, Ar, Kr, etc.) and process gas used in the high-hydrogen process (including a mixture of H2 and N2), as well as reactive gases used in the embodiments of this application (such as oxidizing gases, carbon-oxygen gases, nitrogen-hydrogen gases, etc.). Process gases and reactive gases entering the upper cavity can be excited by the excited gas to form plasma. As the plasma passes through the filter plate 12 into the lower cavity, charged particles are filtered out by the filter plate 12. If necessary, the filter plate 12 can be set to a non-grounded, suspended, de-energized state, allowing charged particles in the plasma to pass through the filter plate 12 and enter the lower cavity. An exhaust port 14 is provided at the bottom of the cavity 10 (lower cavity) for discharging waste gas and controlling the cavity pressure. The semiconductor device can execute the cavity stability control method for high-hydrogen processes provided in this application embodiment through a control system (host computer / slave computer).

[0106] In summary, this application embodiment achieves pre-protection of the filter plate surface and the inner wall of the cavity (Al2O3 layer) by forming a first passivation layer. During the high-hydrogen process, a second passivation layer is further formed on the filter plate surface and the inner wall of the cavity, allowing for online regenerative compaction repair of the damaged first passivation layer. This enables online maintenance while avoiding fluctuations in the high-hydrogen process. This application embodiment avoids hydrogen damage based on the particle formation mechanism, mitigating it at the source of particle generation and establishing a new high-hydrogen process flow. This unifies the etching resistance of the cavity surface, effectively preventing prolonged hydrogen exposure and eliminating etching rate drift in the high-hydrogen process, thereby improving mass production stability and extending the service life of cavity components.

[0107] The above are merely preferred embodiments of this application. These embodiments are not intended to limit the scope of protection of this application. Therefore, any equivalent changes made based on the description and drawings of this application should also be included within the scope of protection of this application.

Claims

1. A method for controlling cavity stability in a high-hydrogen process, wherein the cavity is a plasma processing cavity, a filter plate for filtering charged particles in the plasma is provided in the cavity, and the inner wall surface of the cavity and the surface of the filter plate have an Al2O3 layer, characterized in that, In order, they include: (a) An oxidizing gas is introduced into the cavity and a continuous plasma mode is activated to perform the first activation treatment on the surface of the Al2O3 layer; (b) Introduce carbon-containing oxygen gas, nitrogen-containing hydrogen gas, and a first mixed gas of hydrogen and nitrogen into the cavity, and turn on the continuous plasma mode to react on the surface of the Al2O3 layer to form an interfacial composite anchoring layer containing Al-OC interface covalent anchoring bonds and Al-N interface covalent anchoring bonds. (c) Introduce carbon-oxygen gas and a second mixed gas of hydrogen and nitrogen into the cavity, and activate the periodic cyclic pulse plasma mode to react and form a first passivation layer with an Al-OCN three-dimensional mesh skeleton structure on the basis of the interface composite anchoring layer. (d) Introduce a third mixture of hydrogen and nitrogen into the cavity and activate the continuous plasma mode to complete the high-hydrogen process with a preset number of treatments; (e) Introduce carbon-oxygen gas and a fourth mixed gas of hydrogen and nitrogen into the cavity, and activate the periodic cyclic pulse plasma mode to react and form a second passivation layer with an Al-OCN three-dimensional mesh skeleton structure on the basis of the first passivation layer, so as to repair the damaged first passivation layer. Repeat steps (d) to (e), and when the total duration of the high-hydrogen process meets the threshold, repeat steps (a) to (c).

2. The cavity stability control method under high-hydrogen process according to claim 1, characterized in that, The oxidizing gas includes O2; and / or, the carbon-oxygen gas includes CO; and / or, the nitrogen-hydrogen gas includes NH3; and / or, the hydrogen flow rate in the first mixed gas accounts for less than 4%, and the nitrogen flow rate accounts for more than 96%; and / or, the hydrogen flow rate in the second mixed gas, the third mixed gas, and the fourth mixed gas accounts for more than 4% to 40%, and the nitrogen flow rate accounts for less than 96% to 60%; and / or, when performing (a) to (e), the cavity temperature is 150℃ to 500℃; and / or, when performing (b), the flow rates of the nitrogen-hydrogen gas, the carbon-oxygen gas, and the first mixed gas increase sequentially; and / or, when performing (b), (c), and (e), the partial pressure of the carbon-oxygen gas is less than 30 mTorr.

3. The cavity stability control method under high-hydrogen process according to claim 1, characterized in that, In step (a), after the first activation treatment, the process further includes: Argon gas was introduced into the cavity, and continuous plasma mode was activated to perform a second activation treatment on the surface of the Al2O3 layer.

4. The cavity stability control method under high-hydrogen process according to claim 1, characterized in that, In step (c), after forming the first passivation layer, the method further includes: A fifth mixed gas of hydrogen and nitrogen is introduced into the cavity, and a continuous plasma mode is activated to perform plasma annealing and bonding treatment on the first passivation layer.

5. The cavity stability control method under high-hydrogen process according to claim 4, characterized in that, The hydrogen flow rate in the fifth mixed gas is less than 4%, and the nitrogen flow rate is more than 96%.

6. The cavity stability control method under high-hydrogen process according to claim 4, characterized in that, In step (c), after the plasma annealing and bonding treatment, the process further includes: Nitrogen gas is introduced into the cavity, and the plasma radio frequency is turned off to perform thermal relaxation curing on the first passivation layer.

7. The cavity stability control method under high-hydrogen process according to claim 1, characterized in that, In step (e), after forming the second passivation layer, the method further includes: A sixth mixed gas of hydrogen and nitrogen is introduced into the cavity, and a continuous plasma mode is activated to perform surface passivation treatment on the second passivation layer.

8. The cavity stability control method under high-hydrogen process according to claim 7, characterized in that, The hydrogen flow rate in the sixth mixed gas is less than 4%, and the nitrogen flow rate is more than 96%.

9. The cavity stability control method under high-hydrogen process according to claim 1, characterized in that, In (c), when the periodic cyclic pulse plasma mode is activated, the number of cycles is 10 to 20, the radio frequency on-time in each cycle is 60 to 80 seconds, and the radio frequency off-time is 20 to 40 seconds; and / or, in (e), when the periodic cyclic pulse plasma mode is activated, the number of cycles is 1 to 3, the radio frequency on-time in each cycle is 30 to 50 seconds, and the radio frequency off-time is 10 to 30 seconds; and / or, the preset number of processing times is 1 to 3; and / or, the threshold is 500 hours to 1500 hours; and / or, the thickness of the first passivation layer is 10 nm to 300 nm.

10. A semiconductor device, characterized in that, The semiconductor device includes a cavity and is used to perform the cavity stability control method for high-hydrogen processes as described in any one of claims 1-9.

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