Method and apparatus for cleaning yttria-coated part for semiconductor dry etching system while forming yttrium oxyfluoride on the part

Abstract

This invention relates to a fluorination cleaning method and apparatus for forming yttrium oxide coated elements in a semiconductor dry etching apparatus. The method includes: an element placement step, in which a yttrium oxide coated assembly is placed in a processing chamber; a process gas injection step, in which a discharge gas, a non-fluorinated reactive gas, and a reactive gas, used as process gases for fluorination cleaning, are injected into the processing chamber; a plasma thermal treatment step, in which heat and plasma are applied to the processing chamber; and a cleaning process control step, in which cleaning is controlled by controlling process factors in the process gas injection step and the plasma thermal treatment step, thereby forming a fluorinated layer on the yttrium oxide coating of the yttrium oxide coated assembly.

Description

Technical Field

[0001] This invention relates to a fluorination cleaning method and apparatus for forming yttrium oxyfluoride (YOF) layers on yttrium oxide (Y2O3) coatings of semiconductor dry etching equipment components. More specifically, it relates to a fluorination cleaning method and apparatus for forming yttrium oxyfluoride (YOF) layers on yttrium oxide (Y2O3) coatings of semiconductor dry etching equipment components through plasma thermal treatment with process gases including CF4 reactive gas and specific processing conditions. This shortens the aging process time, enabling normal etching rates to be achieved during the seasoning process of the dry etching equipment. Prior Technology

[0002] When semiconductor dry etching equipment in semiconductor equipment is shut down due to periodic equipment inspections or component replacements (maintenance), a backup process is required before restarting the equipment to resume normal operation of the semiconductor manufacturing equipment.

[0003] In semiconductor dry etching equipment, the commissioning process involves several steps, namely: an out-gasing step to remove moisture and other contaminants from the equipment; a step to reduce contaminants (parts) within the equipment; an aging step within the fluorinated equipment; and a step to perform sample quality testing using mass-produced wafers (in the Fab. Data database).

[0004] This process involves an aging process to create a fluorinated atmosphere inside the semiconductor dry etching equipment that enables a normal etching rate. This aging process involves reacting the surface of a plasma-resistant coating (Al2O3, Y2O3, YAG, etc.) installed inside the equipment with a specified level of corrosive gas to form a fluorinated layer on the surface containing a component of F element ranging from a few nm to several hundred nm.

[0005] If a fluorinated atmosphere is not sufficiently formed inside the semiconductor dry etching equipment, the normal etching process time will be greatly reduced as the aging process is repeated, which may lead to a decrease in the productivity of the semiconductor equipment and an increase in manufacturing costs.

[0006] On the other hand, as an existing example of a method for forming a fluorinated layer, there is a known method in which the component to be fluorinated is loaded into a vacuum chamber, and then a low-pressure vacuum plasma containing fluorine gases such as CF4, SF6, and NF3 is generated, thereby passing through the fluorine-containing free radical fluorinated surface (“Fabrication, characterization, and fluorine- plasma exposure behavior of dense yttrium oxyfluoride ceramic”, T Tsunoura et al, Japanese Journal of Applied Physics 56, 06HC02 (2017), “Fluorination mechanisms of Al2O3 and Y2O3 surfaces irradiated by high-density CF4 / O2 and SF6 / O2 plasmas”, K Miwa et al, J Vac Sci Technol A 27(4), Jul / Aug 2009).

[0007] However, this method has the following drawbacks: it is not conducive to mass production and has low economic efficiency because it requires the construction of a vacuum tank and vacuum equipment. Moreover, due to the use of low-pressure plasma process, the density of fluorine-containing free radicals is low, which leads to slow fluorination speed and thus reduces productivity.

[0008] Furthermore, as another example, there is a known method of fluorinating the surface by immersing the component to be fluorinated in solutions such as HF, SF4, and CHF3 and then raising the temperature to ~250°C ("Preparation of Fluorinated-γ-Alumina", E Kemnitz et al, "Efficient Preparations of Fluorine Compounds", Edited by HW Roesky, 2013, 442).

[0009] However, this method has the following drawbacks: it is detrimental to process safety because it uses hazardous solutions during operation and processing.

[0010] Furthermore, as another example, there are U.S. Patent US8206829 and / or U.S. Publication Patent US2017 / 0114440. These documents disclose methods for coating powder materials such as AlF3, YF3, AlOF, and YOF onto the surface of components using methods such as plasma spraying.

[0011] However, the raw materials AlF3 or YF3 used as coating materials for ceramic protective films such as alumina (Al2O3) or yttrium oxide (Y2O3) are very expensive, and the limited number of raw material suppliers leads to supply problems, resulting in low economic efficiency. Furthermore, when fluorination coating is performed using this method, the physical impact caused by ionic particles in the plasma may generate more particles than Y2O3, thus reducing the reliability of fluorination coating.

[0012] Patent documents Korean Patent Publication No. 10-1309716 (Published on September 17, 2013) U.S. Patent Publication No. 8,206,829 (Granted June 26, 2012) U.S. Patent Publication No. 2017 / 0114440 (Published on April 27, 2017) Summary of the Invention

[0013] The problem that the invention aims to solve

[0014] Therefore, the object of the present invention for solving the above-mentioned existing problems is to provide a fluorination cleaning method and fluorination cleaning equipment for forming yttrium oxyfluoride (YOF) layer on yttrium oxide (Y2O3) coating of semiconductor dry etching equipment components through plasma thermal treatment containing process gas including CF4 reactive gas and specific processing conditions, thereby shortening the aging process time and achieving a normal etching rate during the seasoning process of dry etching equipment.

[0015] The technical problems of this invention are not limited to those mentioned above. Those skilled in the art to which this invention pertains can clearly understand other technical problems not mentioned from the following description.

[0016] Technical means to solve the problem

[0017] According to an aspect of the invention for achieving this object and other features, a fluorination cleaning method for forming yttrium oxide coated elements in a semiconductor dry etching apparatus is provided. This method for cleaning elements (parts) with a yttrium oxide (Y₂O₃) coating in a semiconductor dry etching apparatus includes: an element placement step, placing the yttrium oxide coated assembly in a processing chamber; a process gas injection step, injecting a discharge gas, a non-fluorinated reactive gas, and a reactive gas as process gases for fluorination cleaning into the processing chamber; a plasma thermal treatment step, applying heat and plasma to the processing chamber; and a cleaning process control step, controlling the cleaning process by controlling process factors in the process gas injection step and the plasma thermal treatment step, thereby forming a fluorinated layer on the yttrium oxide coating of the yttrium oxide coated assembly.

[0018] In this invention, during the cleaning process control step, multiple process processing factors, including process gas injection volume, plasma generation power, processing time, heat treatment temperature, processing space pressure, distance between plasma and components, and processing cycle, can be combined and controlled.

[0019] In this invention, the process control step can control the process factors to form a yttrium fluoride layer on the yttrium oxide coating of the yttrium oxide coating assembly.

[0020] In this invention, the plasma generation power, heat treatment temperature, treatment space pressure, process gas flow rate, and process time, which are process factors, can be controlled in the cleaning process control step.

[0021] In this invention, preferably, in the cleaning process control step, the plasma generation power (radio frequency (RF) power) is controlled to be 100W~1200W, the heat treatment temperature is controlled to be room temperature~600℃, the processing space pressure is controlled to be 90mTorr~110mTorr, the flow ratio of non-fluorine reactive gas to fluorine-containing reactive gas CF4 is controlled to be 0:100, and the process time is controlled to be 15 minutes~180 minutes.

[0022] In this invention, the cleaning process control step can control the low-frequency (LF) plasma generation power, heat treatment temperature, processing space pressure, process gas flow rate, and process time, which are process factors.

[0023] In this invention, preferably, in the cleaning process control step, the low-frequency (LF) plasma generation power is controlled to be 300W~1200W, the heat treatment temperature is controlled to be room temperature~600℃, the processing space pressure is controlled to be 90mTorr~550mTorr, the flow ratio of discharge gas Ar to non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4 is controlled to be 0:(10~90):(10~90) or 50:(10~50):(18~45), and the process time is controlled to be 15 minutes~60 minutes.

[0024] In this invention, the process control step of the cleaning process can control process processing factors, including plasma generation power, flow ratio of non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4, and process processing time, as well as at least one of the following: distance between plasma and component, and process processing cycle.

[0025] In this invention, preferably, in the cleaning process control step, the low-frequency (LF) plasma generation power is controlled to be 1kW~7kW, the flow ratio of non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4 is 90:10 or 0:100, the process time is 15 minutes~60 minutes, and the distance between the plasma and the element is 30mm~50mm.

[0026] In this invention, during the cleaning process control step, at least one of the following factors can be controlled: microwave remote plasma generation power, bias plasma power, flow ratio of non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4, and process time.

[0027] In this invention, preferably, in the cleaning process control step, the power of the microwave remote plasma generator is controlled to be 1kW~2kW, the power of the bias plasma is controlled to be 500W~1000W (2MHz plasma), the flow ratio of non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4 is controlled to be 10:1, and the process time is controlled to be 15 minutes.

[0028] Compared with the efficacy of previous technologies

[0029] The fluorination cleaning method and fluorination cleaning equipment for yttrium oxide coated elements in semiconductor dry etching equipment provided by the present invention offer the following advantages.

[0030] First, the advantage of this invention is that it can shorten the aging time to achieve a normal etching rate during the seasoning process of semiconductor dry etching equipment, thereby improving productivity.

[0031] Secondly, the advantage of this invention is that it has excellent device compatibility because the composition of YOF can be adjusted.

[0032] Third, the advantage of this invention is that it can increase the coating life of plasma-resistant coating material components, thereby increasing economic efficiency.

[0033] Fourth, the advantages of this invention are that it can achieve high density and high strength of semiconductor dry etching equipment components coated with yttrium oxide (Y2O3), and can minimize the generation of contaminant particles suitable for normal etching rates. Simple Explanation of the Diagram

[0034] Figure 1 is a flowchart illustrating the fluorination cleaning method of the present invention for forming yttrium oxide coated elements for use in semiconductor dry etching equipment.

[0035] Figure 2 is a schematic diagram illustrating the plasma generation mode of the first embodiment of the fluorination cleaning method for forming yttrium oxide coated elements in a semiconductor dry etching apparatus according to the present invention, which includes a cleaning process control step.

[0036] Figure 3 is a schematic diagram illustrating the plasma generation mode of the second embodiment of the fluorination cleaning method for forming yttrium oxide-coated elements in a semiconductor dry etching apparatus according to the present invention, which includes a cleaning process control step.

[0037] Figure 4 is a schematic diagram illustrating the plasma generation mode of the third embodiment of the fluorination cleaning method for forming yttrium oxide coated elements in a semiconductor dry etching apparatus according to the present invention, which includes a cleaning process control step.

[0038] Figure 5 is a schematic diagram illustrating the plasma generation mode of the fourth embodiment of the fluorination cleaning method for forming yttrium oxide coated elements in a semiconductor dry etching apparatus according to the present invention, which includes a cleaning process control step.

[0039] Figure 6 shows the results of electron microscopy measurements of the coating of the element after fluorination cleaning using the fluorination cleaning method of the present invention for forming yttrium oxide coated elements in semiconductor dry etching equipment.

[0040] Figure 7 is a block diagram illustrating, in block form, the structure of the fluorination cleaning apparatus for forming yttrium oxide fluorination of a yttrium oxide coating assembly in a semiconductor dry etching apparatus according to the present invention.

[0041] Figure 8 is a graph showing the results of comparing surface microstructure based on O2 flow rate and C and F content based on surface and depth.

[0042] Figure 9 is a graph showing the results of comparing surface microstructure based on power and F content based on surface and reaction layer depth under the RIE mode.

[0043] Figure 10 is a graph showing the results of comparing surface / section microstructure according to reaction temperature and F content according to surface and depth.

[0044] Figure 11 is a graph showing the XRD analysis results based on the reaction temperature.

[0045] Figure 12 is a graph showing the results of comparing surface microstructure according to power and F content according to surface and depth.

[0046] Figure 13 is a graph showing the results of comparing surface microstructure according to reaction time and F and C content according to surface and depth.

[0047] Figure 14 is a graph showing the results of comparing surface microstructure based on chamber working pressure (processing pressure) and F content based on surface and depth.

[0048] Figure 15 is a graph showing the results of comparing surface microstructure based on the gas flow ratio of O2 to CF4, and the F and C contents based on the surface and depth.

[0049] Figure 16 is a graph showing the comparison of surface microstructure and EDS analysis results in floating mode based on distance from the electrode, low-frequency (LF) plasma power, and reaction time.

[0050] Figure 17 is a graph showing the results of comparing surface microstructure and F content based on power and reaction time.

[0051] Figure 18 is a graph showing the Y2O3 fluorination cleaning results using the process treatment factors of the fourth embodiment. Implementation

[0052] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The terminology used in this specification and claims should not be limited to its conventional or dictionary meaning, but rather should be interpreted in accordance with the meaning and concept consistent with the technical idea.

[0053] The embodiments and structures shown in the drawings described in this specification are only preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, from the perspective of this application, there may be a variety of equivalent technical solutions and modifications that can replace them.

[0054] The additional objects, features and advantages of the present invention will become more apparent from the following detailed description and drawings.

[0055] Before describing the invention in detail, it is possible to seek various modifications and have various embodiments. The following description and the illustrations shown in the figures are not intended to limit the invention to a specific implementation, but rather to include all modifications, equivalent technical solutions or alternative technical solutions within the scope of the invention's ideas and description.

[0056] When a structural element is referred to as being "connected" or "linked" to other structural elements, it can mean that the connection or link is direct or that other structural elements exist in between. Conversely, when a structural element is "directly connected" or "directly linked" to other structural elements, it should be understood that no other structural elements exist in between.

[0057] The terminology used in this specification is for illustrative purposes only and is not intended to limit the invention. Unless otherwise indicated in the context, singular expressions include plural expressions. In this specification, terms such as "comprising" or "having" are used to specify the presence of features, digits, steps, actions, structural elements, components, or combinations thereof described in the specification, and do not preclude the presence or additional possibilities of one or more other features, digits, steps, actions, structural elements, components, or combinations thereof.

[0058] Furthermore, the terms "section," "unit," and "module" used in the instruction manual refer to units that handle at least one function or action, which can be embodied through hardware, software, or a combination of hardware and software.

[0059] Furthermore, in the description with reference to the drawings, regardless of the component symbols, the same component symbols are assigned to the same structural elements, and detailed descriptions of these are omitted. In describing the present invention, detailed descriptions of related prior art will be omitted if it is determined that a detailed description of the prior art would obscure the main points of the present invention.

[0060] Hereinafter, with reference to the accompanying drawings, a fluorination cleaning method and fluorination cleaning equipment for forming yttrium oxide coated elements in a semiconductor dry etching apparatus according to a preferred embodiment of the present invention will be described in detail.

[0061] Figure 1 is a flowchart illustrating the fluorination cleaning method for forming yttrium oxyfluoride-coated elements for semiconductor dry etching equipment according to the present invention. Figure 2 is a schematic diagram illustrating the plasma generation mode of the first embodiment executed in the cleaning process control step of the fluorination cleaning method for forming yttrium oxyfluoride-coated elements for semiconductor dry etching equipment according to the present invention. Figure 3 is a schematic diagram illustrating the plasma generation mode of the second embodiment executed in the cleaning process control step of the fluorination cleaning method for forming yttrium oxyfluoride-coated elements for semiconductor dry etching equipment according to the present invention. Figure 4 is a schematic diagram illustrating the plasma generation mode of the third embodiment of the fluorination cleaning method for forming yttrium oxide-coated elements in a semiconductor dry etching apparatus according to the present invention, which includes the cleaning process control step. Figure 5 is a schematic diagram illustrating the plasma generation mode of the fourth embodiment of the fluorination cleaning method for forming yttrium oxide-coated elements in a semiconductor dry etching apparatus according to the present invention, which includes the cleaning process control step. Figure 6 shows the results of measuring the coating of the element using an electron microscope after fluorination cleaning using the fluorination cleaning method for forming yttrium oxide-coated elements in a semiconductor dry etching apparatus according to the present invention.

[0062] The present invention provides a fluorination cleaning method for forming yttrium oxide-coated elements in a semiconductor dry etching apparatus. As a method for cleaning elements (parts) with plasma-resistant yttrium oxide (Y2O3) coatings in a semiconductor dry etching apparatus, as shown in Figures 1 to 6, the method mainly includes an element placement step S100, a process gas injection step S200, a plasma heat treatment step S300, and a cleaning process control step S400.

[0063] Specifically, the fluorination cleaning method for forming yttrium oxide-coated elements in a semiconductor dry etching apparatus according to the present invention, as a method for cleaning elements (parts) having a plasma-resistant yttrium oxide (Y2O3) coating in a semiconductor dry etching apparatus, as shown in Figures 1 to 6, includes: an element placement step S100, in which a yttrium oxide-coated assembly is placed in the processing chamber of the fluorination cleaning apparatus; a process gas injection step S200, in which Ar as a discharge gas, O2 as a non-fluorinated reaction gas, and CF4 reaction gas are injected as process gases into the processing space of the processing chamber in which the element is placed in the element placement step S100; and a plasma heat treatment step S3. 00, plasma is generated in the processing space by creating a thermal environment with a specified temperature and applying a specified plasma generation power; and in the cleaning process control step S400, the control module controls multiple process factors, including the amount of gas injected in the process gas injection step S200, the plasma generation power in the plasma heat treatment step S300, the processing time, the heat treatment temperature, the processing space pressure, the distance between the plasma and the component (the distance between the plasma generation unit and the component), and the process cycle, to clean the component so that yttrium fluoride oxyfluoride (YOF) is formed on the coating of the component.

[0064] For example, the element placement step S100 involves placing a yttrium oxide coated element in a processing chamber with a plasma reaction space (processing space), such that during the process of exposure to plasma, the yttrium oxide coated element to be cleaned can be placed on the upper end of a bracket located in the processing space and the door of the processing chamber can be closed to isolate the processing space from the outside.

[0065] The following will describe in detail the fluorinated cleaning equipment used in the component placement step S100.

[0066] Next, the process gas injection step S200 is a process of injecting Ar as a discharge gas, O2 as a non-fluorine reaction gas, and CF4 reaction gas as process gases into the processing space at a flow rate controlled in the cleaning process control step S400.

[0067] In the gas injection step S200 of this process, in addition to Ar gas, inert gases such as He, Ne, Ar, Kr, and Xe can also be used as discharge gases. Furthermore, in addition to oxygen (O2) gas, nitrogen (N2) and air can be used as non-fluorinated reaction gases. And, in addition to CF4 gas, fluorinated reaction gases such as C2F6 and C4F8, or nitrogen trifluoride (NF3) gas can be used, but in this invention, preferably, the discharge gas is argon (Ar), the non-fluorinated reaction gas is oxygen (O2), and the fluorinated reaction gas is carbon tetrafluoride (CF4).

[0068] Next, in the plasma heat treatment step S300, a heating element installed in the processing space is used to create a thermal environment with a specified temperature inside the processing space, and a specified plasma generation power is applied through the plasma generation device to generate plasma in the processing space.

[0069] The plasma heat treatment step S300 is performed simultaneously with the process factors of plasma generation and heat treatment controlled by the cleaning process control step S400 described later.

[0070] Next, in the cleaning process control step S400, multiple process processing factors, including the amount of gas injected in the process gas injection step S200, the plasma and heat treatment related parameters in the plasma heat treatment step S300, the processing space pressure, the distance between the plasma and the component (the distance between the plasma RF voltage application electrode and the target component), and the process processing factors of the processing cycle, are combined and controlled.

[0071] The cleaning process control step S400 can utilize methods classified according to the plasma source methods used in known plasma etching processes, such as reactive ion etching (RIE), plasma etching (PE), and remote plasma source (RPS). It can also utilize a floating plasma source method that forms a floating potential.

[0072] Specifically, in the first embodiment, in the cleaning process control step S400, the plasma generation power, heat treatment temperature (i.e., element temperature), processing space pressure, process gas flow rate, and process time, which are process processing factors, are controlled.

[0073] Preferably, the cleaning process control step S400 of the first embodiment is the RIE mode shown in FIG2, wherein the plasma generation power (radio frequency (RF) / low frequency (LF) plasma power) as a process processing factor is 100W~1200W (preferably 100W~300W), the heat treatment temperature (i.e., element temperature) is room temperature~600℃ (preferably 250℃~300℃), the processing working pressure is 90mTorr~110mTorr (preferably 100mTorr), the flow ratio of non-fluorine reactive gas to fluorine-containing reactive gas CF4 is 0:100, and the process processing time is 15 minutes~180 minutes.

[0074] The cleaning process control mode of this first embodiment can be highly reactive and regulate the heat treatment temperature, and perform cleaning to form yttrium fluoride oxyfluoride (YOF) on the coating of the component.

[0075] Next, in the second embodiment, in the cleaning process control step S400, the low-frequency (LF) plasma generation power, heat treatment temperature (i.e., element temperature), processing space pressure, process gas flow rate, and process time, which are process processing factors, are controlled.

[0076] Preferably, the cleaning process control step S400 of the second embodiment is the PE mode shown in FIG3. The low-frequency (LF) plasma generation power as a process processing factor is 300W~1200W, the heat treatment temperature (i.e., element temperature) is room temperature~600℃ (preferably 250℃~300℃), the processing working pressure is 90mTorr~550mTorr (preferably 100mTorr~500mTorr), the flow ratio of discharge gas Ar to non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4 is 0:(10~90):(10~90) or 50:(10~50):(18~45), and the process processing time is 15 minutes~60 minutes.

[0077] The cleaning process control mode of this second embodiment can ensure large-area uniformity of yttrium oxyfluoride (YOF) formation based on the arrangement of plasma generating electrodes.

[0078] Next, in the third embodiment, in the cleaning process control step S400, the process processing factors may include the low-frequency (LF) plasma generation power, the ratio of non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4, and the process processing time. It may also include the distance between the plasma and the element (the distance between the plasma generating electrode and the element as the target) and / or the process processing cycle (reaction time).

[0079] Preferably, the cleaning process control step S400 of the third embodiment is a floating mode as shown in FIG4. The low-frequency (LF) plasma generation power as a process processing factor can be 1kW~7kW, the ratio of non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4 can be 90:10 or 0:100, and the process processing time can be 10 minutes~70 minutes (preferably 10 minutes~60 minutes). In addition to the distance between the plasma and the element and / or the process processing cycle, preferably, the distance between the plasma and the element is 30mm~140mm (preferably 40mm), and the process processing time is 15min~60min.

[0080] The cleaning process control mode of this third embodiment can reduce or prevent arcing caused by overcurrent flowing to a certain part and resulting in a further increase in voltage, and can ensure the large-area uniformity of yttrium oxyfluoride (YOF) formation according to the arrangement of plasma generating electrodes.

[0081] The third embodiment described above utilizes a floating plasma source to form a floating potential. A floating potential refers to the potential of an element when it is in a plasma state. When surrounding electrons and ions collide with the sample, the electron velocity is faster than the ion velocity per unit time, so the element has a negative (-) potential. At a certain instant, the number of electrons entering and the number of cations entering reach a balance, and the current becomes 0. This potential is called a floating potential.

[0082] Next, in the fourth embodiment, as shown in FIG5, the process control step S400 includes microwave remote plasma generation power, bias plasma power, flow ratio of non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4, and process time as process factors.

[0083] Preferably, the cleaning process control step S400 of the fourth embodiment is the plasma mode shown in FIG5. Preferably, the microwave far-end plasma generation power, which is a process factor, is 1kW~2kW, the bias plasma power is 500W~1000W (2MHz plasma), the flow ratio of non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4 is 10:1, and the process time is 15 minutes.

[0084] The cleaning process control mode of this fourth embodiment is a method of cleaning by generating an interaction between the plasma and the component at a location far from the plasma. The cleaning process control method of the fourth embodiment can react with the surface to form yttrium fluoride oxyfluoride (YOF) without the direct influence of the plasma.

[0085] Next, with reference to the accompanying drawings, a fluorination cleaning apparatus for forming yttrium oxyfluoride of yttrium oxide for yttrium oxide-coated elements in a semiconductor dry etching apparatus, for performing the above-described fluorination cleaning method for forming yttrium oxyfluoride of yttrium oxide-coated elements in a semiconductor dry etching apparatus, will be described in detail.

[0086] Figure 7 is a block diagram illustrating, in block form, the structure of the fluorination cleaning apparatus for forming yttrium oxide fluorination of a yttrium oxide coating assembly in a semiconductor dry etching apparatus according to the present invention.

[0087] The fluorination cleaning equipment for yttrium oxide coated components in semiconductor dry etching equipment of the present invention is a fluorination cleaning equipment for cleaning components (parts) with plasma-resistant yttrium oxide (Y2O3) coating in semiconductor dry etching equipment. As shown in FIG7, it mainly includes a plasma-heat treatment device 100, process gas supply devices 210, 220, 230 and a control module 300.

[0088] Specifically, the fluorination cleaning equipment for forming yttrium oxide coated components in semiconductor dry etching equipment according to the present invention is a fluorination cleaning equipment for cleaning components (parts) with plasma-resistant yttrium oxide (Y2O3) coatings in semiconductor dry etching equipment. As shown in FIG7, it includes: a plasma-thermal treatment unit configured to perform plasma thermal treatment on the component P with plasma-resistant yttrium oxide (Y2O3) coating disposed inside; process gas supply units 210, 220, and 230 configured to supply discharge gas, non-fluorinated reaction gas, and reaction gas as process gases to the plasma-thermal treatment unit; and a control module unit 300 configured to control the plasma thermal treatment environment of the plasma-thermal treatment unit and the injection of process gases supplied from the process gas supply units 210, 220, and 230.

[0089] This plasma-thermal treatment apparatus is for performing plasma thermal treatment on a component P having a plasma-resistant yttrium oxide (Y2O3) coating. It includes: a process chamber body 110 with a processing space 111 inside; a process gas injection port 120 located on one side (upper side in the figure) of the process chamber body 110 for injecting process gas into the processing space 111; a process gas exhaust port 130 located on the other side (lower side in the figure) of the process chamber body 110 for discharging process gas; heating components 140 and 141 located inside the process chamber body 110; a plasma generating electrode located in the process chamber body 110; and a support plate 170 located within the process chamber body 110 for loading the component P.

[0090] The main body 110 of the process chamber is formed in a cylindrical shape and has an opening and closing part (not shown) on one side. The gas flow path element is loaded through the opening and closing part, and the interior is kept airtight when the opening and closing part is closed.

[0091] Furthermore, as another embodiment, the process chamber body 110 can be configured such that the lower part forming the bottom is separated from the upper part. The lower part can be configured to move up and down via an up-down drive device (not shown), thereby enabling it to rise after loading components in the lowered state to close the processing space of the process chamber body 110.

[0092] The process gas injection port 120 can be located at the center of the upper surface of the process chamber body 110, and the process gas discharge port 130 can be located at the center of the lower surface of the process chamber body 110.

[0093] The heating element is configured to heat plate-shaped elements such as shower heads and / or cylindrical components such as liner bushings.

[0094] As one embodiment, the heating element may be composed of a plurality of annular heaters 140 arranged concentrically around the center of the process chamber body 110 along the radial direction, and may be configured to be installed in the process chamber body 110 by a cross-shaped mounting means (not shown).

[0095] The heating element can be composed of a spiral heater, a coil heater, or a ring heater 140.

[0096] Furthermore, in another embodiment, the heating element is composed of a ceramic heater 141 disposed along the inner wall of the process chamber body 110.

[0097] This heating element 141 can be configured such that the U-shaped heater is continuously arranged in a zigzag pattern along the inner wall of the process chamber body 110. The heating element 141 can be composed of a spiral ceramic heater, a coil ceramic heater, or a plate ceramic heater.

[0098] In this fluorination cleaning equipment, heating components of one embodiment and another embodiment can be provided respectively, or heating components of both embodiments can be provided simultaneously.

[0099] Next, the plasma generating electrode is configured to include a grounded electrode and a non-grounded electrode as a plasma voltage application electrode. As an embodiment, the non-grounded electrode can be composed of a plate-shaped electrode on which the yttrium oxide coated element P is placed. That is, the support plate 170 can be composed of a non-grounded electrode.

[0100] Furthermore, regarding the ungrounded electrode, since the process gas outlet 130 is formed at the center of the lower surface, the ungrounded electrode interface 160 is combined with one side edge of the support plate 170, so the other side of the plate electrode is supported and fixed by a bracket (not shown).

[0101] Furthermore, the ungrounded electrodes are configured to be spaced apart along the radial direction inside the process chamber body 110, and cylindrical yttrium oxide coating components such as liner are provided between the spaces.

[0102] Specifically, the non-grounded electrode includes: a first power electrode 151, which is arranged concentrically with the center of the process chamber body 110 on the inner side (i.e., relatively close to the center); and a second power electrode 152, which is spaced apart from the first power electrode 151 and arranged on the outer side.

[0103] Viewed from above, the first power electrode 151 and the second power electrode 152 are arranged in a circular shape. For example, they can be configured as U-shaped electrode components arranged continuously in a cylindrical shape.

[0104] In this case, the support plate 170 includes a substrate and a ceramic plate disposed on the upper surface of the substrate, such that the lower end of the cylindrical element P is located on its upper surface.

[0105] Furthermore, the support plate component 170 can be configured to be rotated from the bottom of the process chamber body 110 via a rotary drive unit (not shown).

[0106] On the other hand, the plasma-thermal treatment apparatus may also include a diffusion member 180 located on the side of the process gas injection port 120 in the processing space 111 of the process chamber body, so that the process gas injected through its process gas injection port 120 diffuses.

[0107] The diffusion component 180 can be composed of a diffusion plate disposed at a predetermined distance from the injection end of the process gas injection port 120. The diffusion plate can be formed in a plate shape as shown in the figure, and can be composed of a dome-shaped plate or a triangular plate.

[0108] Next, the process gas supply units 210, 220, and 230 are configured to supply discharge gas, non-fluorine reaction gas, and reaction gas to the plasma-thermal treatment units 100 and 200, respectively.

[0109] The process gas supply units 210, 220, and 230 are configured to inject Ar (as a discharge gas), O2 (as a non-fluorine reaction gas), and CF4 (as a CF4 reaction gas) as process gases into the processing space 111 at controlled flow rates under the control of the control unit 300.

[0110] Besides Ar gas, inert gases such as He, Ne, Ar, Kr, and Xe can also be used as the discharge gas. Furthermore, besides oxygen (O2) gas, nitrogen (N2) and air can be used as the non-fluorine reactant gas. And besides CF4 gas, fluorine-containing reactant gases such as C2F6 and C4F8, or nitrogen trifluoride (NF3) gas can be used, but in this invention, it is preferable that the discharge gas is argon (Ar), the non-fluorine reactant gas is oxygen (O2), and the fluorine-containing reactant gas is carbon tetrafluoride (CF4).

[0111] Furthermore, the control module 300 is a structure configured to control the plasma heat treatment environment of the plasma-heat treatment apparatus 100 and 200 and the injection of process gas supplied from the process gas supply apparatus 210, 220 and 230. By combining and controlling multiple process processing factors, including the process gas injection amount, plasma generation power, processing time, heat treatment temperature, processing space pressure and processing cycle, a yttrium fluoride oxyfluoride (YOF) layer of a specified thickness is formed on the yttrium oxide coated element.

[0112] On the other hand, the inventors of the present invention have confirmed through experiments the processing control included in the fluorination cleaning method for forming yttrium oxide coated elements for semiconductor dry etching equipment, and have described it.

[0113] First, the experimental results obtained by the fluorination cleaning method using the process processing factors of the first embodiment will be explained with reference to Figures 8 to 11.

[0114] Figure 8 shows a graph comparing the surface microstructure based on O2 flow rate and the C and F contents based on surface and depth. EDS and XPS depth profiling results confirm that as oxygen flow rate increases, C content decreases and F content increases, indicating the presence of an appropriate O2 flow rate for carbon removal. When O2 flow rate increases and CF4 flow rate decreases, F reaction decreases. Figure 9 shows a graph comparing the surface microstructure based on power and the F content based on surface and reaction layer depth under RIE mode, confirming that as power increases, F content increases.

[0115] Figure 10 shows a graph comparing the surface / cross-sectional microstructure and the F content based on surface and depth according to reaction temperature. It confirms that as the reaction temperature increases, the F content increases, the F reaction layer thickness increases, and the microstructure particle size increases. Figure 11 shows the XRD analysis results based on reaction temperature. It confirms the change in Y₂O₃ crystal structure according to temperature. There is no difference in the Y₂O₃ crystal structure after fluorination at room temperature (RT) to 300℃, and it confirms the peak of the YOF crystal after fluorination at 500℃. A YOF layer of approximately 500 nm was observed in the sample fluorinated at 500℃.

[0116] Next, the experimental results obtained by the fluorination cleaning method using the process treatment factors of the second embodiment will be described with reference to Figures 12 to 15.

[0117] Figures 12 and 13 are graphs showing the results of comparing the surface microstructure based on power and reaction time in PE mode, and the F and C contents based on the surface and depth. The EDS analysis results confirm that the F content does not change when the power is increased above 600W, but the XPS analysis results confirm that the F content on the surface increases slightly when the power is increased.

[0118] Figure 14 is a graph showing the comparison of microstructure based on chamber working pressure (processing pressure) and F content based on surface and depth. EDS and XPS depth profiling results confirm that F content decreases as chamber working pressure increases. This is because ion scattering increases with increasing chamber working pressure, leading to a decrease in F reaction.

[0119] Figure 15 is a graph showing the results of comparing the microstructure based on the gas flow ratio of O2 to CF4 and the F content based on the surface and depth. The EDS and XPS depth profiling results confirm that when the O2 flow rate increases, the C content decreases, but the F content does not change.

[0120] Next, the experimental results obtained by the fluorination cleaning method utilizing the process treatment factors of the third embodiment will be described with reference to Figures 16 and 17.

[0121] Figure 16 shows the EDS analysis results based on the distance to the plasma generating electrode, power, and reaction time under the process conditions of 7kW, 250mT, O2:CF4=9:1, distance (D)=40mm, and 15min. Figure 17 shows the evaluation results of fluorination cleaning based on plasma power and reaction time. It is confirmed that outside the range of process conditions, as the distance between the plasma generating electrode and the sample increases, the F content decreases; and as the plasma power increases, the F content increases. Furthermore, it is confirmed that when the reaction time is greater than 60min, the F content increases slightly, but the F content above a certain concentration is meaningless because there is a risk of particle generation during the etching process. In other words, it is confirmed that when the reaction time is greater than 60min, there is a risk that the F content may decrease due to etching.

[0122] Next, the experimental results obtained by the fluorination cleaning method using the process treatment factors of the fourth embodiment will be explained with reference to FIG18.

[0123] Figure 18 is a graph showing the Y2O3 fluorination cleaning results using the process treatment factors of the fourth embodiment. The F content is in the order of remote plasma < remote plasma-Bias < low frequency (LF) plasma, confirming that LF plasma is the most suitable for surface reaction.

[0124] The fluorination cleaning method and fluorination cleaning equipment for yttrium oxide coated elements in semiconductor dry etching equipment according to the present invention, as described above, have the advantages of shortening the aging time required to achieve a normal etching rate during the seasoning process of the semiconductor dry etching equipment for yttrium oxide (Y2O3) coatings in the etching equipment, thereby improving productivity, and having excellent equipment compatibility because the composition of YOF can be adjusted.

[0125] Furthermore, the advantages of this invention are that it can increase the coating life of plasma-resistant coating material components, thereby increasing economic efficiency, and can achieve high density and high strength of yttrium oxide (Y2O3) coated semiconductor dry etching equipment components, while minimizing the generation of contaminant particles used for normal etching rates.

[0126] The embodiments and drawings described in this specification are merely illustrative of some of the technical ideas included in this invention. Therefore, the embodiments disclosed in this specification are not intended to limit the technical ideas of this invention, but rather to illustrate them. It is therefore obvious that the scope of the technical ideas of this invention is not limited to these embodiments. All modifications and specific embodiments that can be readily deduced by those skilled in the art within the scope of the technical ideas included in this specification and drawings should be interpreted as being covered within the scope of this invention.

[0127] P: Component 100, 200: Plasma-Heat Treatment Equipment Section 110: Main body of the process chamber 111: Space Processing Department 120: Process gas injection port 130: Process gas exhaust port 140: Annular heater 141: Ceramic heater 151: First power electrode 152: Second power electrode 160: Non-grounded electrode connection interface 170: Support plate 180: Diffusion component 210, 220, 230: Process gas supply unit section 300: Control Device Section S100, S200, S300, S400: Steps

Claims

1. A fluorination cleaning method for forming yttrium oxyfluoride coatings on yttrium oxide-coated elements in a semiconductor dry etching apparatus, comprising: In the component placement step, a yttrium oxide-coated assembly is placed in a processing chamber; The process includes a process gas injection step, in which a discharge gas, a non-fluorinated reactive gas, and a reactive gas are injected into the processing chamber as process gases for fluorination cleaning; a plasma thermal treatment step, in which heat and plasma are applied to the processing chamber; and a cleaning process control step, in which cleaning is controlled by controlling process processing factors of the process gas injection step and the plasma thermal treatment step, so that a fluorinated layer is formed on the yttrium oxide coating of the yttrium oxide coated assembly. In the cleaning process control step, process processing factors are controlled to form a fluorinated yttrium oxide layer on the yttrium oxide coating of the yttrium oxide coated assembly. The process processing factors include microwave far-end plasma generation power, bias plasma power, flow ratio of non-fluorinated reactive gas O2 to fluorinated reactive gas CF4, and process processing time.

2. The fluorination cleaning method for forming yttrium oxyfluoride for yttrium oxide-coated elements in a semiconductor dry etching apparatus as described in claim 1, wherein, In this cleaning process control step, the power of the microwave remote plasma is controlled to be 1kW to 2kW, the power of the bias plasma (i.e., 2MHz plasma power) is 500W to 1000W, the flow ratio of non-fluorine reactive gas O2 to fluorine-containing reactive gas CF4 is 10:1, and the process time is 15 minutes.

Images