Substrate processing method

Abstract

Disclosed is a method for cleaning a component which is used in an apparatus for processing a substrate using plasma and provided so as to be exposed to the plasma. According to one embodiment, the method may comprise: a first step of removing impurities formed on the surface of the component by using a first solution; and a second step of improving the surface roughness of the component by using a second solution after the first step. Accordingly, impurities formed on the inner wall of a plasma chamber made of quartz can be removed, and the roughness of the inner wall of the plasma chamber can be improved.

Description

Substrate processing method

[0001] The present invention relates to a method for processing a substrate, and more specifically, to a method for processing a substrate by conditioning a plasma chamber.

[0002] Various processes, such as deposition, photolithography, etching, and cleaning, are performed to manufacture semiconductor devices or flat panel displays. Among these processes, the etching process is a process that removes specific parts of a wafer to form a desired pattern.

[0003] Plasma is used to form patterns in the etching process. However, if the plasma contains oxygen, it causes the problem of oxidizing the pattern. Accordingly, a method has been proposed to perform the etching process using a plasma containing hydrogen instead of oxygen.

[0004] However, using a hydrogen-containing plasma caused problems such as corroding components in the plasma generation area and inducing a large amount of impurities on the substrate.

[0005] In particular, when plasma is formed using gases containing nitrogen and hydrogen, such as diimide (H2N2) and ammonia (NH3), hydrogen radicals and hydrogen ions within the plasma react with quartz (SiO2) components provided in the chamber, removing oxygen atoms and replacing them with nitrogen atoms to form a SixNy layer on the surface of the quartz. This deformation of the surface of the quartz components causes impurities and leads to problems that impair processing efficiency and reduce the lifespan of the device.

[0006] One objective of the present invention is to provide a substrate treatment method capable of removing impurities formed on the inner wall of a plasma chamber.

[0007] In addition, the present invention has one objective of providing a substrate treatment method capable of restoring the inner wall of a damaged plasma chamber.

[0008] In addition, the present invention has one objective of providing a substrate processing method that can improve the processing efficiency of the process.

[0009] In addition, the present invention has one objective of providing a substrate processing method that prevents the lifespan of the equipment from being shortened and maintains the quality and stability of the process.

[0010] The objectives of the present invention are not limited thereto, and other unmentioned objectives will be clearly understood by those skilled in the art from the description below.

[0011] The present invention discloses a method for processing a substrate. According to one embodiment, the method comprises: a substrate processing step of applying high-frequency power to a plasma source to generate plasma from a processing gas containing nitrogen and hydrogen in a plasma generation space and processing a substrate with said plasma in a processing chamber that provides a processing space; and a plasma chamber conditioning step of conditioning the plasma chamber that provides the plasma generation space, wherein the plasma chamber conditioning step comprises: a first conditioning step of supplying a first conditioning gas containing oxygen gas and nitrogen gas to the plasma generation space and applying a first power to the plasma source to condition the inner wall of the plasma chamber with plasma generated from said first conditioning gas; and a second conditioning step of, after the first conditioning step, supplying a second conditioning gas containing nitrogen gas to the plasma generation space and applying a second power to the plasma source to condition the inner wall of the plasma chamber with plasma generated from said second conditioning gas, wherein the first power may be greater than the second power.

[0012] According to one embodiment, the second conditioning gas may further include oxygen gas.

[0013] According to one embodiment, the volume ratio of the oxygen gas in the second conditioning gas may be lower than the volume ratio of the oxygen gas in the first conditioning gas.

[0014] According to one embodiment, after the second conditioning step, a third conditioning gas comprising the nitrogen gas and the oxygen gas is supplied to the plasma generation space, and the second power is applied to the plasma source to condition the inner wall of the plasma chamber with the plasma generated from the third conditioning gas, and the volume ratio of the oxygen gas in the third conditioning gas may be lower than the volume ratio of the oxygen gas in the second conditioning gas.

[0015] According to one embodiment, the plasma chamber conditioning step may further include a fourth conditioning step of conditioning the inner wall of the plasma chamber with a fourth conditioning gas comprising only the nitrogen gas among the oxygen gas and the nitrogen gas.

[0016] According to one embodiment, the second conditioning gas may include only the nitrogen gas among the oxygen gas and the nitrogen gas.

[0017] According to one embodiment, the plasma chamber conditioning step may include a pressure reduction step after the second conditioning step, wherein the pressure of the plasma generation space is reduced without supplying gas to the plasma generation space.

[0018] According to one embodiment, the volume ratio of the oxygen gas in the first conditioning gas may be 90%.

[0019] According to one embodiment, the volume ratio of the oxygen gas in the second conditioning gas may be 60%.

[0020] According to one embodiment, the volume ratio of the oxygen gas in the third conditioning gas may be 30%.

[0021] According to one embodiment, the plasma chamber conditioning step may be performed after the substrate processing step has been performed a plurality of times.

[0022] According to one embodiment, the inner wall of the plasma chamber may be made of quartz.

[0023] According to one embodiment, the treatment gas may be H2N2(diimide) or NH3(ammonia).

[0024] Additionally, the present invention discloses another method for processing a substrate. According to one embodiment, the method comprises: a substrate processing step of generating plasma from a processing gas in a plasma generation space by applying high-frequency power to a plasma source and processing a substrate with said plasma in a processing chamber that provides a processing space; and a plasma chamber conditioning step of conditioning the plasma chamber that provides the plasma generation space, wherein the plasma chamber conditioning step comprises: a first conditioning step of supplying a first conditioning gas to the plasma generation space and conditioning the inner wall of the plasma chamber with plasma generated from said first conditioning gas by applying a first power to the plasma source. After the first conditioning step, a second conditioning step is included in which a second conditioning gas is supplied to the plasma generation space and a second power is applied to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the second conditioning gas, wherein the first conditioning gas comprises a first gas and a second gas different from the first gas, the second conditioning gas comprises the second gas, and the first power may be greater than the second power.

[0025] According to one embodiment, the second conditioning gas further comprises the first gas, and the volume ratio of the first gas in the second conditioning gas may be lower than the volume ratio of the first gas in the first conditioning gas.

[0026] According to one embodiment, after the second conditioning step, a third conditioning gas comprising the first gas and the second gas is supplied to the plasma generation space, and the second power is applied to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the third conditioning gas, and the volume ratio of the first gas in the third conditioning gas may be lower than the volume ratio of the first gas in the second conditioning gas.

[0027] According to one embodiment, the plasma chamber conditioning step may further include a fourth conditioning step of conditioning the inner wall of the plasma chamber with a fourth conditioning gas comprising only the second gas.

[0028] According to one embodiment, the inner wall of the plasma chamber is provided with a quartz material, and the processing gas includes nitrogen and oxygen, the first gas may be oxygen gas, and the second gas may be nitrogen gas.

[0029] Additionally, the present invention discloses another method for processing a substrate. According to one embodiment, the method comprises: a substrate processing step of applying high-frequency power to a plasma source to generate plasma from a processing gas containing nitrogen and hydrogen in a plasma generation space and processing a substrate with said plasma in a processing chamber that provides a processing space; and a conditioning step of removing impurities attached to the inner wall of a plasma chamber that provides a plasma generation space generated during the substrate processing step and restoring the inner wall of said plasma chamber, wherein the plasma chamber conditioning step comprises: a first conditioning step of removing impurities attached to the inner wall of said plasma chamber and restoring the inner wall of said plasma chamber; and a first conditioning step of supplying a first conditioning gas mixed with oxygen gas and nitrogen gas to the plasma generation space and applying a first power to the plasma source to condition the inner wall of said plasma chamber with plasma generated from said first conditioning gas. A second conditioning step, after the first conditioning step, in which a second conditioning gas containing nitrogen gas is supplied to the plasma generation space and a second power is applied to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the second conditioning gas; a third conditioning step, after the second conditioning step, in which a third conditioning gas containing the nitrogen gas and the oxygen gas is supplied to the plasma generation space and the second power is applied to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the third conditioning gas; and a fourth conditioning step, after the third conditioning step, in which a fourth conditioning gas containing only the nitrogen gas is supplied to the plasma generation space and the second power is applied to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the third conditioning gas.and after the second conditioning step, a depressurization step of depressurizing the plasma generation space without supplying gas to the plasma generation space is included, wherein the volume ratio of the oxygen gas in the second conditioning gas is lower than the volume ratio of the oxygen gas in the first conditioning gas, the volume ratio of the oxygen gas in the third conditioning gas is lower than the volume ratio of the oxygen gas in the second conditioning gas, the inner wall of the plasma chamber is provided with a quartz material, and the first power may be greater than the second power.

[0030] According to one embodiment, the treatment gas may be H2N2(diimide) or NH3(ammonia).

[0031] According to one embodiment of the present invention, impurities formed on the inner wall of a plasma chamber can be removed.

[0032] In addition, according to one embodiment of the present invention, the inner wall of a damaged plasma chamber can be restored.

[0033] In addition, according to one embodiment of the present invention, the processing efficiency of the process can be improved.

[0034] In addition, according to one embodiment of the present invention, the lifespan of the equipment can be prevented from being shortened, and the quality and stability of the process can be maintained.

[0035] The effects of the present invention are not limited to the effects described above, and unmentioned effects will be clearly understood by those skilled in the art from this specification and the attached drawings.

[0036] The various features and benefits of the non-limiting embodiments of this specification may become more apparent from a review of the detailed description in conjunction with the accompanying drawings. The accompanying drawings are provided for illustrative purposes only and should not be construed as limiting the claims. Unless expressly stated otherwise, the accompanying drawings are not to be drawn to scale. For clarity, various dimensions in the drawings may be exaggerated.

[0037] FIG. 1 is a drawing showing an embodiment of a substrate processing apparatus in which a substrate processing method according to an embodiment of the present invention is performed.

[0038] FIG. 2 is a flowchart illustrating a substrate processing method according to one embodiment of the present invention.

[0039] Figure 3 is a graph showing the effect of the plasma chamber conditioning step of Figure 2 of the present invention on the inner wall of the plasma chamber.

[0040] Figure 4 is a graph showing the effect of the plasma chamber conditioning step of Figure 2 of the present invention on the number of particles on the substrate.

[0041] Figure 5 is a graph showing the effect of the frequency of the plasma chamber conditioning step of Figure 2 of the present invention.

[0042] FIG. 6 is a drawing showing another embodiment of a substrate processing apparatus that performs the substrate processing method of the present invention.

[0043] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. Exemplary embodiments are provided to ensure that the present disclosure is thorough and will fully convey its scope to those skilled in the art. To provide a complete understanding of the embodiments of the present disclosure, many specific details, such as examples of specific components, devices, and methods, are presented. It will be apparent to those skilled in the art that specific details are not necessary, that exemplary embodiments may be implemented in many different forms, and that neither should be interpreted as limiting the scope of the present disclosure. In some exemplary embodiments, known processes, known device structures, and known technologies are not described in detail.

[0044] The terms used herein are merely for describing specific exemplary embodiments and are not intended to limit exemplary embodiments. Singular expressions or expressions where singularity is not specified, as used herein, are intended to include plural expressions unless the context clearly indicates otherwise. The terms “comprising,” “comprising,” “having,” and “having” are open-ended and thus specify the presence of the mentioned features, components, steps, operations, elements, and / or components, and do not exclude the presence or addition of one or more other features, components, steps, operations, elements, components, and / or groups thereof. Method steps, processes, and operations in this specification are not to be interpreted as necessarily being performed in the specific order discussed or described unless the order of performance is specified. Additionally, additional or alternative steps may be selected.

[0045] When an element or layer is referred to as being "on," "connected," "combined," "attached," "adjacent," or "covering" another element or layer, it may be directly on, connected to, combined with, attached to, adjacent to, or covering said other element or layer, or intermediate elements or layers may exist. Conversely, when an element is referred to as being "directly on," "directly connected to," or "directly combined" with another element or layer, it should be understood that intermediate elements or layers do not exist. Throughout the specification, the same reference numerals refer to the same elements. The term "and / or" as used in the present invention includes all combinations and non-combinations of one or more of the listed items.

[0046] Although terms such as first, second, third, etc., may be used to describe various elements, regions, layers, and / or sections in the present invention, it should be understood that these elements, regions, layers, and / or sections are not limited by these terms. These terms are used merely to distinguish one element, region, layer, or section from another element, region, layer, or section. Accordingly, the first element, first region, first layer, or first section discussed below may be referred to as the second element, second region, second layer, or second section without departing from the teachings of the exemplary embodiments.

[0047] Spatially relative terms (e.g., "below," "under," "lower," "above," "top," etc.) may be used for convenience of explanation to describe the relationship between one element or feature and another element(s) or feature(s) as illustrated in the drawings. It should be understood that spatially relative terms are intended to include not only the orientations illustrated in the drawings but also other orientations of the device in use or operation. For example, if the device in the drawings is inverted, elements described as "below" or "under" other elements or features will be oriented "above" other elements or features. Thus, the term "below" may include both upper and lower orientations. The device may be oriented differently (rotated 90 degrees or in a different orientation), and the spatially relative descriptive terms used in the present invention may be interpreted accordingly.

[0048] It should be understood that there may be some inaccuracy when the terms "identical" or "same" are used in the description of the embodiments. Therefore, if one element or value is referred to as identical to another element or value, it should be understood that said element or value is identical to another element or value within a manufacturing or operating tolerance (e.g., ±10%).

[0049] Where the words “approximately” or “substantially” are used in this specification with respect to figures, it should be understood that such figures include a manufacturing or operational tolerance (e.g., ±10%) of the figures mentioned. Additionally, where the words “generally” and “substantially” are used with respect to geometric forms, it should be understood that while geometric accuracy is not required, freedom of form (latitude) is within the scope of disclosure.

[0050] Unless otherwise defined, all terms used in the present invention (including technical and scientific terms) have the same meaning as generally understood by those skilled in the art to which the exemplary embodiments belong. Furthermore, terms, including those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with that meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in the present invention.

[0051] In this embodiment, a wafer is used as an example of the object to be processed. However, the technical concept of the present invention may be applied to devices used for processing other types of substrates besides wafers as the object to be processed.

[0052] A substrate processing apparatus in which the substrate processing method of the present invention is performed is provided as an apparatus that performs a predetermined process on a substrate (W) using remote plasma. For example, the substrate processing apparatus may etch or ashash a thin film on the substrate (W). The thin film may be of various types of films, such as a polysilicon film, an oxide film, and a silicon nitride film. Optionally, the thin film may be a natural oxide film or a chemically generated oxide film.

[0053] FIG. 1 is a drawing showing an embodiment of a substrate processing apparatus in which a substrate processing method according to an embodiment of the present invention is performed. Referring to FIG. 1, the substrate processing apparatus (10) may include a processing chamber (100), an exhausting unit (200), a plasma source (300), and an induction unit (340).

[0054] The processing chamber (100) provides a space where a substrate (W) is placed and processing is performed on the substrate (W). Plasma generated by a plasma source (300) described later is supplied to the internal space of the processing chamber (100). Gas remaining inside the processing chamber (100) and / or reaction byproducts generated during the process of processing the substrate (W) can be discharged to the outside of the substrate processing device (10) through an exhaust unit (200) described later. As a result, the pressure inside the processing chamber (100) can be maintained at a set pressure.

[0055] The processing chamber (100) may include a housing (110), a support unit (120), a baffle (130), and an exhaust baffle (140).

[0056] A processing space (111) for performing a substrate processing process is provided inside the housing (110). The outer wall of the housing (110) may be provided with a conductor. For example, the outer wall of the housing (110) may be provided with a metal material including aluminum. The top of the housing (110) may be open, and an opening (not shown) may be formed in the side wall. A substrate (W) enters and exits the interior of the housing (110) through the opening. The opening (not shown) may be opened and closed by an opening / closing member such as a door (not shown). Additionally, an exhaust hole (112) may be formed on the bottom surface of the housing (110). The exhaust hole (112) may be connected to components included in the exhaust unit (200) described later.

[0057] A support unit (120) may be located in a processing space (111). The support unit (120) supports a substrate (W) in the processing space (111). A substrate (W) requiring processing is placed on the upper surface of the support unit (120). The support unit (120) may include a support plate (121) and a support shaft (122).

[0058] The support plate (121) may be provided in a generally circular shape when viewed from above. The support plate (121) is supported by a support shaft (122). The support plate (121) may be connected to an external power source (not shown). The support plate (121) may generate static electricity by power applied from the external power source. The electrostatic force of the generated static electricity can fix the substrate (W) to the upper surface of the support plate (121). However, it is not limited thereto, and the support plate (121) may support the substrate (W) by a physical method such as mechanical clamping or by a vacuum suction method.

[0059] The support shaft (122) can move an object. For example, the support shaft (122) can move a substrate (W) in an up-and-down direction. As an example, the support shaft (122) is coupled with a support plate (121), and by raising and lowering the support plate (121), the substrate (W) placed on the upper surface of the support plate (121) can be moved up and down.

[0060] The baffle (130) is located on the upper part of the support plate (121). The baffle (130) may be positioned between the support plate (121) and the plasma source (300). The baffle (130) may be provided with aluminum material with an oxidized surface. The baffle (130) may be electrically connected to the upper wall of the housing (110). The baffle (130) may be provided in a generally thick disc shape. The baffle (130) may be provided in a generally circular shape when viewed from above. The baffle (130) may be positioned to overlap with the upper surface of the support unit (120) when viewed from above.

[0061] Baffle holes (131) are formed in the baffle (130). Multiple baffle holes (131) may be provided. The baffle holes (131) may be provided spaced apart from each other. For example, the baffle holes (131) may be formed at regular intervals on a concentric circumference for uniform radical supply. The baffle holes (131) may penetrate from the top to the bottom of the baffle (130). The baffle holes (131) may function as a passage through which plasma generated from the plasma source (300) flows into the processing space (111).

[0062] The baffle (130) can uniformly transfer plasma generated from the plasma source (300) to the processing space (111). Additionally, plasma diffused in the diffusion space (341) described later can pass through the baffle holes (131) and flow into the processing space (111). According to one example, charged particles such as electrons or ions are trapped in the baffle (130), and neutral particles that do not carry a charge, such as oxygen radicals, can pass through the baffle holes (131) and be supplied to the substrate (W). Additionally, the baffle (130) can be grounded to form a passage through which electrons or ions move.

[0063] Although the baffle (130) according to one embodiment of the present invention described above has been explained as being provided in the shape of a disc having thickness, it is not limited thereto. The baffle (130) according to one embodiment may have a circular shape when viewed from above, but may have a shape in which the height of its upper surface increases from the edge region to the center region when viewed from a cross-section. As an example, the baffle (130) may have a shape in which its upper surface slopes upward from the edge region to the center region when viewed from a cross-section. Accordingly, plasma generated from the plasma source (300) can flow to the edge region of the processing space (111) along the inclined cross-section of the baffle (130).

[0064] The exhaust baffle (140) uniformly exhausts plasma in the processing space (111) by region. Additionally, the exhaust baffle (140) can control the residence time of the plasma flowing within the processing space (111). When viewed from above, the exhaust baffle (140) has an annular ring shape. The exhaust baffle (140) may be located between the inner wall of the housing (110) and the support unit (120) within the processing space (111). A plurality of exhaust holes (141) are formed in the exhaust baffle (140). The exhaust holes (141) may be provided as holes extending from the top to the bottom of the exhaust baffle (140). The exhaust holes (141) may be arranged spaced apart from each other along the circumferential direction of the exhaust baffle (140). The reaction byproducts that have passed through the exhaust baffle (140) are discharged to the outside through the exhaust lines (201, 202) described later so as to be discharged to the outside of the processing chamber (100).

[0065] The exhaust unit (200) can exhaust gases, particles, by-products, etc. from the processing space (111) to the outside. The exhaust unit (200) can exhaust foreign substances and particles, etc. generated during the process of processing the substrate (W) to the outside of the substrate processing device (10). The exhaust unit (200) may include exhaust lines (201, 202) and a pressure reduction member (210). The exhaust lines (201, 202) function as passages through which plasma and / or reaction by-products remaining in the processing space (111) are discharged to the outside of the substrate processing device (10). The exhaust lines (201, 202) may be connected to an exhaust hole (112) formed on the bottom surface of the housing (110). The exhaust lines (201, 202) may be connected to a pressure reduction member (210) that provides negative pressure.

[0066] The pressure reducing member (210) can provide negative pressure to the processing space (111). The pressure reducing member (210) can discharge plasma, foreign substances, byproducts, or particles remaining in the processing space (111) to the outside of the housing (110). Additionally, the pressure reducing member (210) can provide negative pressure to maintain the pressure in the processing space (111) at a preset pressure. The pressure reducing member (210) may be a pump. However, it is not limited thereto, and the pressure reducing member (210) may be provided in various modified forms as a known device that provides negative pressure.

[0067] The plasma source (300) generates plasma by exciting the gas supplied to the discharge space (311). The plasma source (300) generates plasma by applying high-frequency power to the discharge space (311) to the discharge space (311). The plasma source (300) may be located above the processing chamber (100). Additionally, the plasma source (300) may be located above the housing (110). According to one example, the plasma source (300) may be separated from the processing chamber (100). In this case, the plasma source (300) may be provided outside the processing chamber (100). The plasma source (300) generates plasma from the gas supplied from the gas supply pipe (320) and supplies it to the processing space (111). The plasma source (300) may include a plasma chamber (310), a gas supply pipe (320), an antenna (331), and a power source (332).

[0068] A discharge space (311) is formed inside the plasma chamber (310). The plasma chamber (310) may have a shape with an open top and bottom surface. For example, the plasma chamber (310) may have a cylindrical shape with an open top and bottom surface. The plasma chamber (310) may be provided with a material including quartz, or at least the inner wall of the plasma chamber (310) may be provided with quartz.

[0069] The top of the plasma chamber (310) is sealed by a gas supply port (315). The gas supply port (315) is connected to a gas supply pipe (320). The gas supply pipe (320) includes a branch line that branches into multiple branches and can be connected to multiple gas sources. The multiple gas sources may be provided to supply different gases. For example, the gases may include nitrogen (N2), oxygen (O2), hydrogen (H2), ammonia (NH3), and diimide (H2N2). Optionally, the gases may further include other types of gases, such as tetrafluoromethane (CF4).

[0070] Gas is supplied to the discharge space (311) through the gas supply port (315). The gas supplied to the discharge space (311) can be uniformly distributed to the processing space (111) through the inflow space (341) and baffle hole (131) of the induction unit (340) described later.

[0071] The antenna (331) may be an inductively coupled plasma (ICP) antenna. The antenna (331) may be provided in a coil shape. The antenna (331) may wrap the plasma chamber (310) multiple times around the outside of the plasma chamber (310). For example, the antenna (331) may wrap the plasma chamber (310) multiple times in a spiral shape around the outside of the plasma chamber (310).

[0072] The antenna (331) wraps around the plasma chamber (310) in an area corresponding to the discharge space (311). One end of the antenna (331) may be provided at a height corresponding to the upper area of ​​the plasma chamber (310) when viewed from the front cross-section of the plasma chamber (310). The other end of the antenna (331) may be provided at a height corresponding to the lower area of ​​the plasma chamber (310) when viewed from the front cross-section of the plasma chamber (310). One end of the antenna (331) may be connected to a power source (332), and the other end of the antenna (331) may be grounded. However, it is not limited to this, and one end of the antenna (331) may be grounded, and the power source (332) may be connected to the other end of the antenna (331). The antenna (331) and the plasma chamber (310) may be provided as a single module.

[0073] The power source (332) can apply power to the antenna (331). The power source (332) can apply a high-frequency current to the antenna (331). The high-frequency current applied to the antenna (331) can form an induced electric field in the discharge space (311). The gas supplied to the discharge space (311) can obtain the energy required for ionization from the induced electric field and be converted into a plasma state.

[0074] In the above-described embodiment of the present invention, the antenna (331) and the plasma chamber (310) are provided as a single module, but this is not limited thereto. As an example, the antenna (331) may not be modularized with the plasma chamber (310) and may wrap around the plasma chamber (310) multiple times from the outside of the plasma chamber (310).

[0075] The induction unit (340) is located between the plasma chamber (310) and the housing (110). The induction unit (340) seals the open upper surface of the housing (110). Inside the induction unit (340), an inflow space (341) is provided to diffuse the plasma generated in the discharge space (311). The inflow space (341) connects the processing space (111) and the discharge space (311) and functions as a passage through which the plasma generated in the discharge space (311) is supplied to the processing space (111). The induction unit (340) can generally be formed in the shape of an inverted funnel. The induction unit (340) can have a shape in which the diameter increases from the top to the bottom. The inner surface of the induction unit (340) can be formed of an insulator. The housing (110) and the baffle (130) can be coupled to the bottom of the induction unit (340). The induction unit (340) can be connected to the bottom of the plasma chamber (310). The top of the induction unit (340) and the bottom of the plasma chamber (310) can be connected.

[0076] A substrate (W) processing method according to one embodiment of the present invention may include a substrate processing step (S100) and a plasma chamber conditioning step (S200).

[0077] The substrate processing step (S100) is a step of bringing a substrate (W) into a processing chamber (100) and forming a plasma to process the substrate (W). A plasma source (300) generates plasma in a discharge space (311), and the generated plasma is transferred to the processing chamber (100) by an induction unit (340). Subsequently, the substrate (W) is processed by the plasma within the processing chamber (100). During the process of generating plasma, as high power is applied, a strong magnetic field is formed in the discharge space, and ions collide strongly with the inner wall of the plasma chamber (310), causing damage to the inner wall of the plasma chamber (310). Additionally, impurities are formed therefrom, and the impurities accumulate on the inner wall of the plasma chamber (310). As the substrate processing step (S100) is repeated, damage accumulates on the inner wall of the plasma chamber (310), and impurities accumulate. This becomes a factor that impairs the processing efficiency, process stability, and lifespan of the device of the substrate (W).

[0078] The plasma chamber conditioning step (S200) is a step of conditioning the inner wall of the plasma chamber (310). Here, conditioning may mean removing impurities formed on the inner wall of the plasma chamber (310) and restoring the damaged inner wall of the plasma chamber (310). The plasma chamber conditioning step (S200) may be performed after a plurality of substrate processing steps (S100). The plasma chamber conditioning step (S200) may include a first conditioning step (S210), a second conditioning step (S220), a third conditioning step (S230), a fourth conditioning step (S240), and a depressurization step (S250).

[0079] The first conditioning step (S210) is a step for removing impurities accumulated on the inner wall of the plasma chamber (310) and restoring the inner wall of the plasma chamber (310). In the first conditioning step (S210), a first conditioning gas is supplied. The first conditioning gas includes a first gas and a second gas. The volume ratio of the first gas is higher than that of the second gas, and can be supplied, for example, at a volume ratio of 9:1. Subsequently, a first power is applied to generate plasma. The first power may be a power in which ions accelerated by the first power collide with impurities formed on the inner wall of the plasma chamber (310) and destroy the impurities. Accordingly, the inner wall of the plasma chamber (310) can be restored.

[0080] The second conditioning step (S220) is a step of restoring the inner wall of the plasma chamber (310). In the second conditioning step (S220), a second conditioning gas is supplied. The second conditioning gas contains a second gas. Optionally, the second conditioning gas may further contain a first gas. If the second conditioning gas contains the first gas, the volume ratio of the first gas in the second conditioning gas may be provided higher than the volume ratio of the second gas. Additionally, the volume ratio of the first gas may be provided lower than the volume ratio of the first gas in the first conditioning gas. For example, the volume ratio of the first gas to the second gas in the second conditioning gas may be supplied in a ratio of 6:4. Subsequently, a second power is applied to generate plasma. The second power can be provided as power that allows the ions accelerated by the second power to restore the inner wall of the plasma chamber (310) without damaging the inner wall of the plasma chamber (310). Accordingly, the roughness of the inner wall of the plasma chamber (310) can be smoothed in the second conditioning step (S220), thereby restoring the inner wall of the plasma chamber (310).

[0081] The third conditioning step (S230) is a step for restoring the inner wall of the plasma chamber (310). In the third conditioning step (S230), a third conditioning gas is supplied. The third conditioning gas includes a first gas and a second gas. The volume ratio of the first gas in the third conditioning gas may be provided lower than the volume ratio of the second gas. Additionally, the volume ratio of the first gas may be provided lower than the volume ratio of the first gas in the first conditioning gas. For example, the volume ratio of the first gas and the second gas in the third conditioning gas may be supplied in a ratio of 3:7. Subsequently, a second power is applied to generate plasma. The second power may be provided at a power level that allows the ions accelerated by the second power to restore the inner wall of the plasma chamber (310) without damaging the inner wall of the plasma chamber (310). In the third conditioning step (S230), the roughness of the inner wall of the plasma chamber (310) is improved (smoothed), so that the inner wall of the plasma chamber (310) can be further restored.

[0082] The fourth conditioning step (S240) is a step for restoring the inner wall of the plasma chamber (310). In the fourth conditioning step (S240), a fourth conditioning gas is supplied. The fourth conditioning gas contains only the second gas. Subsequently, a second power is applied to generate plasma. The second power can be provided as power that allows the ions accelerated by the second power to restore the inner wall of the plasma chamber (310) without damaging the inner wall of the plasma chamber (310). In the fourth conditioning step (S230), the roughness of the inner wall of the plasma chamber (310) is improved (smoothed) so that the inner wall of the plasma chamber (310) can be further restored.

[0083] The depressurization step (S250) is a step of depressurizing the inside of the chamber. By depressurizing the inside of the chamber in the depressurization step (S250), residual impurities can be removed. Additionally, in the depressurization step (S250), the plasma chamber (300) that has undergone the first to fourth conditioning steps (S210, S220, S230, S240) can be stabilized.

[0084] According to one example, the plasma that processes the substrate (W) in the substrate processing step (S100) may be generated by a gas containing nitrogen and hydrogen. For example, the gas containing nitrogen and hydrogen may be H2N2 (diimide) or NH3 (ammonia). Additionally, the inner wall of the plasma chamber (310) may be made of quartz (SiO2) material, and the first gas supplied in the plasma chamber conditioning step (S200) may be oxygen gas and the second gas may be nitrogen gas. Below, the effect of the substrate processing method according to one embodiment of the present invention on the inner wall of the plasma chamber (310) will be explained according to the example described above.

[0085] FIG. 3 is a graph showing the effect of the plasma chamber conditioning step of FIG. 2 of the present invention on the inner wall of the plasma chamber. This graph shows the change in the thickness of SixNy formed on the inner wall of the plasma chamber (310) as the RF time increases. Here, RF time may be the total time during which the substrate processing step (S100) is performed. In FIG. 3, Case A represents a case where only the substrate processing step (S100) is performed during a specific RF time, and Case B represents a case where the plasma chamber conditioning step (S200) is performed together with the substrate processing step (S100) during a specific RF time. In Case B, the ratio of the number of times the substrate processing step (S100) is performed to the number of times the plasma chamber conditioning step (S200) is performed is 25:1. Referring to FIG. 3, if the plasma chamber conditioning step (S200) is not performed, the SixNy series impurities accumulating on the inner wall of the plasma chamber (310) continue to increase as the RF time increases. This is because hydrogen radicals and ions formed when the plasma is generated during the substrate processing step (S100) collide with the inner wall of the plasma chamber (310) to destroy the Si-O bonds, and nitrogen radicals and ions combine with the Si remaining on the inner wall of the plasma chamber (310) to form SixNy series impurities.

[0086] Table 1 below shows the results of EDS analysis of the composition of the inner wall of the plasma chamber (310) as the RF time increases. Referring to Table 1, it can be seen that as the RF time increases, the content of oxygen atoms in the inner wall of the plasma chamber (310) decreases and the content of nitrogen atoms increases. This indicates that during the substrate processing step (S100), hydrogen radicals and ions collide with the inner wall of the plasma chamber (310) to destroy the Si-O bond, and nitrogen radicals and ions combine with the Si remaining on the inner wall of the plasma chamber (310) to form SixNy series impurities.

[0087] RF timeCase ACase BN %O %N%O%1hr1.561.30.462.810hr3.8590.264.5100hr23.622.40.862.5150hr32.916.00.261.1200hr33.416.21.061.0

[0088] FIG. 4 is a graph showing the effect of the plasma chamber conditioning step of FIG. 2 of the present invention on the number of particles on a substrate. Referring to FIG. 4, it can be seen that when the substrate processing step (S100) is performed after the chamber conditioning step (S200), the number of particles induced on the substrate (W) is reduced compared to when only the substrate processing step (S100) is performed. This means that the number of particles induced from the inner wall of the plasma chamber (310) has decreased after the plasma chamber conditioning step (S200).

[0089] Since the substrate (W) cannot be processed while the plasma chamber conditioning step (S200) is being performed, the more frequently the plasma chamber conditioning step (S200) is performed, the longer the lifespan of the plasma source is extended, but the throughput is reduced as it interferes with the substrate processing flow. Accordingly, finding the optimal frequency at which the plasma chamber conditioning step (S200) is performed is significantly important from the perspective of processing efficiency. FIG. 5 is a graph showing the effect of the frequency of the plasma chamber conditioning step of FIG. 2 of the present invention. This graph visually shows the change in thickness of the SixNy film formed over RF time according to the ratio of the substrate processing step (S100) and the plasma chamber conditioning step (S200). Referring to FIG. 5, it was confirmed that the plasma chamber conditioning step (S200) works effectively when the ratio of the substrate processing step (S100) to the plasma chamber conditioning step (S200) is 25:1, but when the ratio is higher than that, SixNy impurities still remain on the inner wall of the plasma chamber (310).

[0090] Generally, when generating a plasma containing nitrogen and hydrogen, hydrogen radicals and hydrogen ions destroy the Si-O bonds on the quartz surface, damaging the quartz surface, and nitrogen radicals and nitrogen ions combine with Si to produce SixNy series impurities. In addition, particles are generated on the substrate (W). This deforms the shape of the plasma chamber (310), impairing process stability and the lifespan of the device, and becomes a factor that reduces the efficiency of the process.

[0091] According to one embodiment of the present invention, by performing a plasma chamber conditioning step (S200), impurities can be removed from the inner wall of a contaminated plasma chamber (310) and the surface of the damaged inner wall can be restored. The impurities are destroyed by colliding with particles having strong ion energy, and the damaged inner wall of the plasma chamber (310) is restored by oxygen atoms penetrating and combining with Si. In addition, the number of particles generated during the substrate processing step (S100) and falling onto the substrate (W) can be reduced.

[0092] In the example described above, the component was explained as a component provided to a device that processes a substrate using remote plasma. However, it is not limited thereto, and the component may also be a component provided to a device that processes a substrate using in-situ plasma. Here, in-situ plasma refers to plasma generated within a process chamber, which is a processing space. FIG. 6 shows an example of a process chamber that processes a substrate using in-situ plasma. Referring to FIG. 6, the process chamber (10) includes a housing (11), an electrostatic chuck (12), an antenna (13), a high-frequency power supply (14), and a gas supply unit (15). The housing (11) provides a processing space for processing a substrate. A number of components made of quartz material, not shown, may be provided in the processing space. The processing space is depressurized by a connected vacuum pump. The electrostatic chuck (11) supports and fixes the substrate (W) in the processing space. The electrostatic chuck (11) is connected to a chiller to control the temperature of the substrate (W). An antenna (13) is provided in a circular or spiral shape and is installed on the upper part of the housing (11). A high-frequency power supply (14) applies a high-frequency voltage to the antenna (13). A gas supply unit (15) supplies gas to the processing space. When the high-frequency power supply (14) applies a high-frequency voltage to the antenna (13), current flows through the antenna (13) to form a magnetic field in the processing space, and the magnetic field forms plasma through the supplied gas. Accordingly, plasma is formed in the same space as the substrate (W).

[0093] In addition, in the above-described embodiments, the method is described based on a flowchart as a series of steps; however, the present invention is not limited to the order of the steps, and some steps may occur in a different order or simultaneously with other steps as described above. Furthermore, those skilled in the art will understand that the steps shown in the flowchart are not exclusive, and other steps may be included, or one or more steps of the flowchart may be omitted without affecting the scope of the present invention. According to one example, a plasma chamber conditioning step (S200) may be performed prior to the substrate processing step (S100). Additionally, at least one of the first conditioning step (S100), the second conditioning step (S200), the third conditioning step (S300), and the fourth conditioning step (S400) may be omitted and may not be performed in the order described.

[0094] In addition, the above example describes a discontinuous change in the volume ratio of the gas supplied at each stage from the first conditioning stage (S210) to the fourth conditioning stage (S240). However, this is merely an example, and the volume ratio of the gas between each stage may be gradually adjusted to reach the target volume ratio of the next stage.

[0095] In addition, in the example described above, plasma is generated using a gas containing nitrogen and hydrogen in the substrate processing step (S100). However, it is not limited to this, and plasma may also be generated using a gas mixed with nitrogen and hydrogen.

[0096] It should be understood that exemplary embodiments are disclosed herein and that other variations may be possible. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but may be interchangeable and used in selected embodiments where applicable, even if not specifically illustrated or described. Such variations should not be construed as departing from the spirit and scope of the present disclosure, and all such variations that are obvious to a person skilled in the art are intended to be included within the scope of the following claims.

Claims

1. Regarding the method of processing the substrate, A substrate processing step of applying high-frequency power to a plasma source to generate plasma from a processing gas containing nitrogen and hydrogen in a plasma generation space, and processing a substrate with said plasma in a processing chamber that provides a processing space; and The method includes a plasma chamber conditioning step for conditioning a plasma chamber that provides the plasma generation space, and The above plasma chamber conditioning step is, A first conditioning step of supplying a first conditioning gas comprising oxygen gas and nitrogen gas to the plasma generation space, and applying a first power to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the first conditioning gas; After the first conditioning step, the method includes a second conditioning step of supplying a second conditioning gas containing nitrogen gas to the plasma generation space and applying a second power to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the second conditioning gas. A substrate processing method in which the first power is greater than the second power.

2. In Paragraph 1, The above second conditioning gas is a substrate processing method that further includes oxygen gas.

3. In Paragraph 2, A substrate treatment method in which the volume ratio of the oxygen gas in the second conditioning gas is lower than the volume ratio of the oxygen gas in the first conditioning gas.

4. In Paragraph 3, After the second conditioning step, the method further includes a third conditioning step of supplying a third conditioning gas comprising the nitrogen gas and the oxygen gas to the plasma generation space and applying the second power to the plasma source to condition the inner wall of the plasma chamber with the plasma generated from the third conditioning gas. A substrate treatment method in which the volume ratio of the oxygen gas in the third conditioning gas is lower than the volume ratio of the oxygen gas in the second conditioning gas.

5. In Paragraph 4, The above plasma chamber conditioning step is, A substrate processing method further comprising a fourth conditioning step of conditioning the inner wall of the plasma chamber with a fourth conditioning gas comprising only the nitrogen gas among the oxygen gas and the nitrogen gas.

6. In Paragraph 1, The above second conditioning gas is, A substrate processing method comprising only the nitrogen gas among the oxygen gas and the nitrogen gas.

7. In Paragraph 1, The above plasma chamber conditioning step is, A substrate processing method comprising, after the second conditioning step, a pressure reduction step of reducing the pressure of the plasma generation space without supplying gas to the plasma generation space.

8. In Paragraph 3, A substrate processing method in which the volume ratio of the oxygen gas in the first conditioning gas is 90%.

9. In Paragraph 8, A substrate processing method in which the volume ratio of the oxygen gas in the second conditioning gas is 60%.

10. In Paragraph 9, A substrate processing method in which the volume ratio of the oxygen gas among the third conditioning gases is 30%.

11. In Paragraph 1, The above plasma chamber conditioning step is, A substrate processing method performed after the above substrate processing step is carried out multiple times.

12. In Paragraph 1, A method for processing a substrate in which the inner wall of the above plasma chamber is made of quartz material.

13. In Paragraph 12, A substrate treatment method in which the above-mentioned treatment gas is H2N2(diimide) or NH3(ammonia).

14. In a method for processing a substrate, A substrate processing step of generating plasma from a processing gas in a plasma generation space by applying high-frequency power to a plasma source, and processing a substrate with said plasma in a processing chamber that provides a processing space; and The method includes a plasma chamber conditioning step for conditioning a plasma chamber that provides the plasma generation space, and The above plasma chamber conditioning step is, A first conditioning step of supplying a first conditioning gas to the plasma generation space and applying a first power to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the first conditioning gas; After the first conditioning step, the method includes a second conditioning step of supplying a second conditioning gas to the plasma generation space and applying a second power to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the second conditioning gas. The first conditioning gas comprises a first gas and a second gas different from the first gas, and The second conditioning gas above includes the second gas, and A substrate processing method in which the first power is greater than the second power.

15. In Paragraph 14, The above second conditioning gas further comprises the above first gas, and A substrate processing method in which the volume ratio of the first gas in the second conditioning gas is lower than the volume ratio of the first gas in the first conditioning gas.

16. In Paragraph 15, After the second conditioning step, the method further includes a third conditioning step of supplying a third conditioning gas comprising the first gas and the second gas to the plasma generation space, and applying the second power to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the third conditioning gas. A substrate processing method in which the volume ratio of the first gas in the third conditioning gas is lower than the volume ratio of the first gas in the second conditioning gas.

17. In Paragraph 16, The above plasma chamber conditioning step is, A substrate processing method further comprising a fourth conditioning step of conditioning the inner wall of the plasma chamber with a fourth conditioning gas containing only the second gas.

18. In Paragraph 17, The inner wall of the above plasma chamber is provided with quartz material, and The above-mentioned treatment gas contains nitrogen and oxygen, and The first gas mentioned above is oxygen gas, and The above second gas is a substrate processing method in which the gas is a viscous gas.

19. In a method for processing a substrate, A substrate processing step of applying high-frequency power to a plasma source to generate plasma from a processing gas containing nitrogen and hydrogen in a plasma generation space, and processing a substrate with said plasma in a processing chamber that provides a processing space; and The method includes a conditioning step for removing impurities attached to the inner wall of a plasma chamber that is generated during the substrate processing step and provides the plasma generation space, and restoring the inner wall of the plasma chamber. The above plasma chamber conditioning step is, A first conditioning step for removing impurities attached to the inner wall of the plasma chamber and restoring the inner wall of the plasma chamber; A first conditioning step of supplying a first conditioning gas, which is a mixture of oxygen gas and nitrogen gas, to the plasma generation space, and applying a first power to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the first conditioning gas; A second conditioning step, after the first conditioning step, wherein a second conditioning gas containing nitrogen gas is supplied to the plasma generation space, and a second power is applied to the plasma source to condition the inner wall of the plasma chamber with plasma generated from the second conditioning gas; A third conditioning step, after the second conditioning step, in which a third conditioning gas comprising the nitrogen gas and the oxygen gas is supplied to the plasma generation space, and the second power is applied to the plasma source to condition the inner wall of the plasma chamber with the plasma generated from the third conditioning gas; and A fourth conditioning step, after the third conditioning step, in which a fourth conditioning gas containing only the nitrogen gas is supplied to the plasma generation space, and the second power is applied to the plasma source to condition the inner wall of the plasma chamber with the plasma generated from the third conditioning gas; and After the second conditioning step, the method includes a pressure reduction step of reducing the pressure of the plasma generation space without supplying gas to the plasma generation space, and The volume ratio of the oxygen gas in the second conditioning gas is lower than the volume ratio of the oxygen gas in the first conditioning gas, and the volume ratio of the oxygen gas in the third conditioning gas is lower than the volume ratio of the oxygen gas in the second conditioning gas. The inner wall of the above plasma chamber is provided with quartz material, and A substrate processing method in which the first power is greater than the second power.

20. In Paragraph 19, A substrate treatment method in which the above-mentioned treatment gas is H2N2(diimide) or NH3(ammonia).

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