A remote plasma cleaning method, cleaning gas set and cleaning system for a semiconductor deposition process chamber
A remote plasma cleaning method that generates active fluorine-containing species outside the semiconductor deposition chamber and separates them from oxygen-containing gases solves the problems of polymerization/redeposition tendency and side reaction pathways in the prior art, and achieves efficient cleaning of silicon-based dielectric deposits and improved cleaning repeatability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 金民宰
- Filing Date
- 2026-01-27
- Publication Date
- 2026-06-02
AI Technical Summary
In existing remote plasma cleaning solutions, the co-activation of fluorine-containing unsaturated organic compounds and oxygen-containing gases in remote regions may cause polymerization/redeposition tendencies or introduce side reaction pathways, resulting in poor cleaning repeatability and engineering controllability.
A remote plasma cleaning method is designed, which generates active fluorine-containing species outside the processing chamber and separates them from oxygen-containing gas inside the processing chamber. The fluorine-containing organic ether compounds are activated using a radio frequency or microwave plasma source, and oxygen-containing gas is introduced through a bypass gas path to avoid direct contact with the discharge area and control the reaction path.
It achieves effective cleaning of silicon-based dielectric deposits, reduces polymerization/redeposition tendency, improves cleaning repeatability and engineering controllability, and reduces over-cleaning and gas consumption through endpoint detection.
Smart Images
Figure CN122136254A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor manufacturing equipment maintenance and cleaning, specifically to a remote plasma cleaning method, cleaning gas group, and cleaning system for semiconductor deposition processing chambers. Background Technology
[0002] In semiconductor PECVD / CVD processes, SiO2 and SiN gradually accumulate on surfaces such as indoor walls, shower heads, and baffles. x The associated silicon-based dielectric deposits can lead to risks related to particle and process drift and yield, thus requiring periodic cleaning.
[0003] Remote plasma cleaning can generate active species outside the treatment chamber and transport them to the chamber for maintenance cleaning. However, some existing methods use fluorinated unsaturated organic compounds (e.g., fluorinated olefins / alkynes) to co-activate with oxygen-containing gases in a remote region, which may cause polymerization / redeposition tendencies or introduce different side reaction pathways under certain conditions.
[0004] Therefore, a cleaning solution based on specific fluorinated organic ether compounds and separating oxygen-containing gas from the remote discharge zone in the process structure is needed to improve cleaning repeatability and engineering controllability. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and meet practical needs by providing a remote plasma cleaning method, cleaning gas group, and cleaning system for semiconductor deposition processing chambers. This addresses the current problem that remote plasma cleaning methods generate active species outside the processing chamber and transport them to the chamber for maintenance cleaning. However, some existing solutions use fluorinated unsaturated organic compounds (e.g., fluorinated olefins / alkynes) and oxygen-containing gases for co-activation in a remote region, which may cause polymerization / redeposition tendencies or introduce different side reaction pathways under certain conditions.
[0006] To achieve the objectives of this invention, the technical solution adopted is as follows: A remote plasma cleaning method for a semiconductor deposition chamber is designed, wherein the chamber is used for chemical vapor deposition or plasma-enhanced chemical vapor deposition to form silicon-based dielectric thin films, comprising the following steps:
[0007] S1, Provide the first gas;
[0008] S2. Introduce the first gas into the discharge region of a remote plasma source, and activate the first gas with plasma in the discharge region to form an activated gas containing active fluorine species.
[0009] S3. The activation gas is introduced into the processing chamber, so that the activation gas comes into contact with the silicon-based dielectric deposit on the inner surface of the processing chamber to remove at least a portion of the deposit;
[0010] S4. Introduce oxygen-containing gas into the processing chamber through a bypass gas path that bypasses the discharge region of the remote plasma source, so that the oxygen-containing gas interacts with the active fluorine-containing species in the processing chamber.
[0011] S5. Discharge the reaction products from the processing chamber to complete the cleaning process.
[0012] Preferably, the silicon-based dielectric deposit is selected from SiO2 and SiN. x One or more of SiON and SiCN.
[0013] Preferably, the pipeline used to transport the first gas and / or oxygen-containing gas is maintained at 30–80°C to suppress condensation.
[0014] Preferably, the oxygen-containing gas does not pass through the discharge region of the remote plasma source, and it is introduced after a delay of t seconds after the start of step S3, where t is 1 to 30 seconds, and the processing chamber pressure is 50 to 2000 mTorr during step S3.
[0015] Preferably, the remote plasma source is a radio frequency plasma source or a microwave plasma source, and its activation power is 200-6000W.
[0016] Preferably, the cleaning endpoint is determined by one or more of OES, exhaust FTIR, pressure change, or mass spectrometry, wherein the gas supply in step S1 is terminated when the cleaning endpoint is reached to reduce over-cleaning.
[0017] A cleaning gas assembly for treating interior surface deposits in semiconductor manufacturing is also provided, comprising:
[0018] The first gas contains compound A and a carrier gas, wherein compound A is CF3CF2OCH2CF3, CAS 156053-88-2;
[0019] And an oxygen-containing gas, selected from one or more of O2, N2O, and CO2, wherein when the oxygen-containing gas is O2, the volume fraction of O2 at the inlet of the processing chamber is 0.1 to 30 vol.
[0020] The oxygen-containing gas is configured to be introduced into the processing chamber via a bypass gas path that bypasses the discharge region of the remote plasma source, and the cleaning gas group has a small amount of fluorinated unsaturated organic compounds with C=C or C≡C bonds and a small amount of NF3. The fluorinated unsaturated organic compounds include fluorinated alkenes and / or fluorinated alkynes.
[0021] In the gas system consisting of the first gas and the oxygen-containing gas, the fluorinated unsaturated organic compounds with a small amount of C=C or C≡C bonds refer to compounds whose content is less than 0.5 mol%, preferably less than 0.1 mol%, i.e., 1000 ppmv, wherein the mixed GWP100 of the gas system is not greater than 2000.
[0022] A cleaning system for treating surface deposits in semiconductor manufacturing is also provided, comprising:
[0023] Compound A supply unit, used to store and supply compound A;
[0024] Carrier gas supply unit;
[0025] A remote plasma source with a discharge region;
[0026] The first gas path delivers the first gas formed by compound A and carrier gas to the discharge region;
[0027] A bypass oxygen path is used to deliver oxygen-containing gas to the processing chamber, wherein the bypass oxygen path bypasses the discharge area;
[0028] An activation gas delivery pipeline is used to introduce the activation gas generated by the remote plasma source into the processing chamber;
[0029] The controller is used to control the operating parameters of the first gas path, the bypass oxygen path, and the remote plasma source;
[0030] The system is configured to use a small amount of fluorinated unsaturated organic compounds having C=C or C≡C bonds during the cleaning process.
[0031] Preferably, the compound A supply unit includes a vaporizer for vaporizing liquid compound A before supplying it; the first gas path includes a mass flow controller (MFC); the bypass oxygen path includes a mass flow controller (MFC) and a valve; the activation gas delivery pipeline includes a heating unit for maintaining the pipeline temperature at 30–80°C; the controller is configured to open the bypass oxygen path after a delay of 1–30 seconds after the activation gas is introduced into the processing chamber; and the controller is configured to terminate the gas supply based on the endpoint signal output by the endpoint detection module.
[0032] Preferably, it also includes an endpoint detection module, which is selected from OES, exhaust FTIR, pressure change detection or mass spectrometry detection.
[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0034] 1. This invention generates fluorine-containing active species by remotely activating fluorine-containing organic ethers with plasma, which can achieve maintenance and cleaning of silicon-based dielectric deposits.
[0035] 2. By excluding fluorine-containing unsaturated organic compounds, the present invention can reduce the tendency of polymerization / redeposition under certain conditions.
[0036] 3. This invention introduces oxygen-containing gas via a bypass (without passing through the discharge zone), which allows for the control of side reaction pathways within the processing chamber, thereby improving repeatability.
[0037] 4. This invention reduces excessive cleaning and gas consumption by terminating gas supply through endpoint detection, and can achieve a lower CO2e impact by combining mixed GWP100 limitation. Attached Figure Description
[0038] Figure 1 This is a schematic diagram of the process of the present invention;
[0039] Figure 2 This is a schematic diagram of the system of the present invention; Detailed Implementation
[0040] The present invention will be further described below with reference to the accompanying drawings and embodiments:
[0041] A remote plasma cleaning method for semiconductor deposition chambers, see [link to relevant documentation]. Figures 1 to 2 The processing chamber is used for chemical vapor deposition or plasma-enhanced chemical vapor deposition to form silicon-based dielectric thin films, including the following steps:
[0042] S1, Provide the first gas;
[0043] S2. Introduce the first gas into the discharge region of the remote plasma source, and activate the first gas with plasma in the discharge region to form an activated gas containing active fluorine species.
[0044] S3. Introduce the activation gas into the processing chamber so that the activation gas comes into contact with the silicon-based dielectric deposit on the inner surface of the processing chamber to remove at least a portion of the deposit;
[0045] S4. Oxygen-containing gas is introduced into the processing chamber through a bypass gas path that bypasses the discharge region of the remote plasma source, so that the oxygen-containing gas interacts with active fluorine-containing species in the processing chamber.
[0046] S5. Discharge the reaction product from the processing chamber to complete the cleaning.
[0047] Specifically, the silicon-based dielectric deposits are selected from SiO2 and SiN. x One or more of SiON and SiCN.
[0048] Furthermore, the pipelines used to transport the first gas and / or oxygen-containing gas are maintained at 30–80°C to suppress condensation.
[0049] It is worth noting that the oxygen-containing gas does not pass through the discharge zone of the remote plasma source, and it is introduced after a delay of t seconds after the start of step S3, where t is 1 to 30 seconds. During step S3, the pressure in the processing chamber is 50 to 2000 mTorr.
[0050] It is worth noting that the remote plasma source is a radio frequency plasma source or a microwave plasma source, and its activation power is 200–6000W.
[0051] It is worth mentioning that the cleaning endpoint is determined by one or more of OES, exhaust FTIR, pressure change, or mass spectrometry, wherein the gas supply in step S1 is terminated when the cleaning endpoint is reached to reduce over-cleaning.
[0052] A cleaning gas assembly for treating interior surface deposits in semiconductor manufacturing is also provided, comprising:
[0053] The first gas contains compound A and a carrier gas. Compound A is CF3CF2OCH2CF3, CAS 156053-88-2.
[0054] And an oxygen-containing gas, selected from one or more of O2, N2O, and CO2, wherein when the oxygen-containing gas is O2, the volume fraction of O2 at the inlet of the processing chamber is 0.1 to 30 vol.
[0055] The oxygen-containing gas is configured to be introduced into the processing chamber through a bypass gas path that bypasses the discharge region of the remote plasma source, and the cleaning gas group has a small amount of fluorinated unsaturated organic compounds with C=C or C≡C bonds and a small amount of NF3. The fluorinated unsaturated organic compounds include fluorinated alkenes and / or fluorinated alkynes.
[0056] In a gas system consisting of a first gas and an oxygen-containing gas, fluorine-containing unsaturated organic compounds with a small amount of C=C or C≡C bonds refer to compounds whose content is less than 0.5 mol%, preferably less than 0.1 mol%, i.e., 1000 ppmv, wherein the mixed GWP100 of the gas system is not greater than 2000.
[0057] A cleaning system for treating surface deposits in semiconductor manufacturing is also provided, comprising:
[0058] Compound A supply unit, used to store and supply compound A;
[0059] Carrier gas supply unit;
[0060] A remote plasma source with a discharge region;
[0061] The first gas path delivers the first gas formed by compound A and the carrier gas to the discharge region;
[0062] A bypass oxygen path is used to deliver oxygen-containing gas to the processing chamber, wherein the bypass oxygen path bypasses the discharge area;
[0063] An activation gas delivery pipeline is used to introduce activation gas generated by a remote plasma source into the processing chamber;
[0064] The controller is used to control the operating parameters of the first gas path, the bypass oxygen path, and the remote plasma source;
[0065] The system is configured to use a small amount of fluorinated unsaturated organic compounds with C=C or C≡C bonds during the cleaning process.
[0066] Notably, the compound A supply unit includes a vaporizer for vaporizing liquid compound A before supplying it. The first gas path includes a mass flow controller (MFC), the bypass oxygen path includes a mass flow controller (MFC) and a valve, and the activation gas delivery pipeline includes a heating unit for maintaining the pipeline temperature at 30–80°C. The controller is configured to open the bypass oxygen path after a delay of 1–30 seconds after the activation gas is introduced into the processing chamber. The controller is also configured to terminate the gas supply based on the endpoint signal output by the endpoint detection module.
[0067] It is worth emphasizing that it also includes an endpoint detection module, which can be selected from OES, exhaust FTIR, pressure change detection or mass spectrometry.
[0068] It should be noted that compound A can be stored in liquid form and vaporized by a vaporizer. After mixing with the carrier gas in the first gas path, it enters the discharge area of the remote plasma source. The activation gas generated by the remote plasma source is introduced into the processing chamber through pipelines.
[0069] Oxygen-containing gas is directly introduced into the treatment chamber inlet or internal area of the treatment chamber via a bypass oxygen path, which does not pass through the discharge zone. The controller coordinates the valves, flow rates, and timing of the first gas path and the bypass oxygen path, and can terminate the cleaning process in conjunction with the endpoint detection module.
[0070] Explanation of excluding unsaturated fluorinated compounds
[0071] In some implementations, fluorinated unsaturated organic compounds (such as fluorinated olefins / alkynes) with C=C or C≡C bonds are not introduced during the cleaning process. Avoiding such unsaturated compounds can reduce the tendency for polymerization / redeposition under certain conditions, thereby improving cleaning repeatability.
[0072] Oxygen bypass injection and timing
[0073] Oxygen-containing gas can be mixed with the activating gas at the inlet of the processing chamber, or enter the processing chamber from different inlets and act together in the processing chamber. Oxygen-containing gas can be injected synchronously or delayed (e.g., delayed by 1 to 30 seconds) to regulate the reaction path and endpoint behavior.
[0074] Example 1
[0075] SiO2 deposition chamber cleaning
[0076] First gas: Compound A vapor + Ar (O2 < 0.1 vol%)
[0077] Remote activation: RF2000W
[0078] Processing chamber pressure: 300~1500mTorr
[0079] Bypass O2: Injected 10 seconds after the start of step S3, so that the inlet O2 is approximately 5 vol%.
[0080] Pipeline temperature: 50°C
[0081] End point: OES / FTIR
[0082] Exclusion: No fluorinated olefin / alkyne unsaturated compounds added.
[0083] Expected outcome: Removal of residual SiO2 and reduction of redeposition risk.
[0084] Example 2
[0085] SiN x Cleaning of sedimentation treatment chamber
[0086] First gas: Compound A vapor + N2
[0087] Bypass O2: Inlet O2 is approximately 10 vol% (does not pass through the discharge zone)
[0088] Expected outcome: Removal of SiN x It leaves residue and maintains a stable gas supply.
[0089] Comparative Example 1
[0090] Bypass oxygen is not used (only activation gas is used).
[0091] Purpose: To compare endpoint time with residual tendency (qualitative / subsequent quantification).
[0092] In addition, all components designed in this invention are general standard parts or components known to those skilled in the art. Their structure and principle can be known to those skilled in the art through technical manuals or conventional experimental methods. Those skilled in the art can fully implement them, so there is no need to elaborate. The content protected by this invention does not involve improvements to the internal structure and method.
Claims
1. A remote plasma cleaning method for a semiconductor deposition chamber, the chamber being used for chemical vapor deposition or plasma-enhanced chemical vapor deposition to form silicon-based dielectric thin films, characterized in that, Includes the following steps: S1, Provide the first gas; S2. Introduce the first gas into the discharge region of the remote plasma source, and activate the first gas in the discharge region to form an activated gas containing active fluorine species. S3. Introduce the activation gas into the processing chamber, so that the activation gas comes into contact with the silicon-based dielectric deposit on the inner surface of the processing chamber to remove at least a portion of the deposit; S4. Oxygen-containing gas is introduced into the processing chamber through a bypass gas path that bypasses the discharge region of the remote plasma source, so that the oxygen-containing gas interacts with active fluorine-containing species in the processing chamber. S5. Discharge the reaction product from the processing chamber to complete the cleaning.
2. The cleaning method as described in claim 1, characterized in that, The silicon-based dielectric deposit is selected from SiO2 and SiN. x One or more of SiON and SiCN.
3. The cleaning method as described in claim 1, characterized in that, Pipelines used to transport the first gas and / or oxygen-containing gas are kept at 30–80°C to suppress condensation.
4. The cleaning method as described in claim 1, characterized in that, The oxygen-containing gas does not pass through the discharge region of the remote plasma source, and it is introduced after a delay of t seconds after the start of step S3, where t is 1 to 30 seconds. During step S3, the pressure in the processing chamber is 50 to 2000 mTorr.
5. The cleaning method as described in claim 1, characterized in that, The remote plasma source is a radio frequency plasma source or a microwave plasma source, and its activation power is 200-6000W.
6. The cleaning method as described in claim 1, characterized in that, The cleaning endpoint is determined by one or more of OES, exhaust FTIR, pressure change, or mass spectrometry, wherein the gas supply in step S1 is terminated when the cleaning endpoint is reached to reduce over-cleaning.
7. A cleaning gas assembly for treating surface deposits in semiconductor manufacturing, applicable to the cleaning method according to any one of claims 1-6, characterized in that, include: The first gas contains compound A and a carrier gas, wherein compound A is CF3CF2OCH2CF3, CAS 156053-88-2; The gas contains an oxygen-containing gas, selected from one or more of O2, N2O, and CO2. When the oxygen-containing gas is O2, the volume fraction of O2 at the inlet of the processing chamber is 0.1–30 vol%. The oxygen-containing gas is configured to be introduced into the processing chamber via a bypass gas path that bypasses the discharge region of the remote plasma source. The cleaning gas group contains a small amount of fluorinated unsaturated organic compounds with C=C or C≡C bonds and a small amount of NF3. The fluorinated unsaturated organic compounds include fluorinated alkenes and / or fluorinated alkynes. In the gas system composed of the first gas and the oxygen-containing gas, the presence of a small amount of fluorinated unsaturated organic compounds with C=C or C≡C bonds means that the content of such compounds is less than 0.5 mol%, preferably less than 0.1 mol%, i.e., 1000 ppmv, wherein the mixed GWP100 of the gas system is not greater than 2000.
8. A cleaning system for treating surface deposits in semiconductor manufacturing, applicable to the cleaning method according to any one of claims 1-6, characterized in that, include: Compound A supply unit, used to store and supply compound A; Carrier gas supply unit; A remote plasma source with a discharge region; The first gas path delivers the first gas formed by compound A and carrier gas to the discharge region; A bypass oxygen path is used to deliver oxygen-containing gas to the processing chamber, wherein the bypass oxygen path bypasses the discharge area; An activation gas delivery pipeline is used to introduce the activation gas generated by the remote plasma source into the processing chamber; The controller is used to control the operating parameters of the first gas path, the bypass oxygen path, and the remote plasma source; The system is configured to use a small amount of fluorinated unsaturated organic compounds having C=C or C≡C bonds during the cleaning process.
9. The cleaning system as described in claim 8, characterized in that, The compound A supply unit includes a vaporizer for vaporizing liquid compound A and supplying it. The first gas path includes a mass flow controller (MFC). The bypass oxygen path includes a mass flow controller (MFC) and a valve. The activation gas delivery pipeline includes a heating unit for maintaining the pipeline temperature at 30–80°C. The controller is configured to open the bypass oxygen path after a delay of 1–30 seconds after the activation gas is introduced into the processing chamber. The controller is configured to terminate the gas supply based on the endpoint signal output by the endpoint detection module.
10. The cleaning system as described in claim 8, characterized in that, It also includes an endpoint detection module, which is selected from OES, exhaust FTIR, pressure change detection or mass spectrometry.