Method for estimating internal state of chamber and device therefor

Abstract

The present disclosure discloses a method by which a chamber monitoring device estimates the state of a chamber. In particular, the method may involve: acquiring Y pieces of reference state data corresponding to Y coordinates in an N-dimensional coordinate system having each of N elements as an axis; generating Y pieces of first state similarity data by calculating the similarity among each of the Y pieces of reference state data and the current state data; determining a multitude of pieces of second state similarity data for all the coordinates by performing at least one of interpolation or extrapolation in the N-dimensional coordinate system on the basis of the Y pieces of first state similarity data; and estimating the current state of each of the N elements according to coordinates included in second state similarity data corresponding to a second state similarity having a maximum value among second state similarities included in the multitude of pieces of second state similarity data.

Description

Method for estimating the internal state of a chamber and device therefor

[0001] The present disclosure relates to a method and a device for estimating the internal state of a chamber. Specifically, the present disclosure relates to a method and a device for estimating the current values ​​of a plurality of elements that can define the internal state of a chamber.

[0002] In addition, the present invention relates to a method and a device for improving the estimation accuracy of current values ​​of multiple elements.

[0003] In semiconductor or display manufacturing and inspection processes, it's crucial to verify that the equipment for the process is within a verified normal range and that process conditions are properly set. While monitoring specific physical quantities of plasma can provide some insight into the ongoing process, directly monitoring the current internal conditions of the chamber, such as the wafer chuck temperature or position, is extremely difficult during the ongoing process.

[0004] Ultimately, we have no choice but to conduct test runs to verify the process results, which incurs additional costs and time. Furthermore, even if the process results are incorrect, it's difficult to identify the cause of the problem.

[0005] Therefore, it is important to estimate the internal state of the chamber, predict possible errors in process results, and accurately discover the causes that may cause problems.

[0006] The present disclosure can provide a method for improving the estimation accuracy of estimating the values ​​of elements defining the internal state of a chamber.

[0007] The problems to be solved in this disclosure are not limited to the problems described above, and problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which this disclosure pertains from this disclosure.

[0008] According to an embodiment of the present disclosure, a method for estimating a state of a chamber by a chamber monitoring device comprises: obtaining Y reference state data corresponding to Y coordinates in an N-dimensional coordinate system having N elements as axes, wherein Y is a natural number greater than or equal to 2 and is a part of all coordinates that can be expressed in the N-dimensional coordinate system, and the N elements are selected from M elements defining the state of the chamber, M is a natural number greater than or equal to 1, N is a natural number greater than or equal to 1, and M is greater than or equal to N; transmitting radio waves of a specific frequency range into the chamber and receiving radio waves reflected from the inside of the chamber; generating current state data representing the state of the chamber based on the received radio waves; calculating a similarity between each of the Y reference state data and the current state data to determine Y first state similarities; The method may include: generating Y first state similarity data by mapping the Y first state similarities and the Y coordinates; determining a plurality of second state similarity data for the entire coordinates by performing at least one of interpolation and extrapolation within the N-dimensional coordinate system based on the Y first state similarity data, wherein each of the plurality of second state similarity data includes a second state similarity for each of the entire coordinates; determining second state similarity data corresponding to a second state similarity having a maximum value among the second state similarities included in the plurality of second state similarity data as estimated state similarity data; and estimating a current state of each of the N elements according to the coordinates included in the estimated state similarity data.

[0009] A chamber monitoring device for estimating the state of a chamber according to the present disclosure comprises: an antenna for transmitting radio waves of a specific frequency range into the interior of the chamber and receiving radio waves reflected from the interior of the chamber; a bracket for fixing the antenna to the interior or exterior of the chamber; a signal processor for applying an electric signal to the antenna and obtaining an electric signal from the antenna; And a controller that controls the signal processing unit and generates state data of the chamber based on an electric signal obtained by the signal processing unit; wherein the controller obtains Y reference state data corresponding to Y coordinates in an N-dimensional coordinate system with each of N elements as an axis, wherein Y is a natural number greater than or equal to 2 and is a part of all coordinates that can be expressed in the N-dimensional coordinate system, and the N elements are selected from M elements defining the state of the chamber, M is a natural number greater than or equal to 1, N is a natural number greater than or equal to 1, and M is greater than or equal to N; controls the signal processor so that the antenna transmits a radio wave of a specific frequency range into the interior of the chamber and receives a radio wave reflected from the interior of the chamber, thereby controlling the signal processor to obtain an electric signal according to the received radio wave; generates current state data representing the state of the chamber based on the received radio wave; calculates a similarity between each of the Y reference state data and the current state data to determine Y first state similarities; By mapping the Y first state similarities and the Y coordinates, Y first state similarity data are generated;Based on the Y first state similarity data, at least one of interpolation and extrapolation is performed within the N-dimensional coordinate system to determine a plurality of second state similarity data for the entire coordinates, wherein each of the plurality of second state similarity data includes a second state similarity for each of the entire coordinates; determining the second state similarity data corresponding to the second state similarity having the maximum value among the second state similarities included in the plurality of second state similarity data as estimated state similarity data; and estimating the current state of each of the N elements according to the coordinates included in the estimated state similarity data;

[0010] According to the present disclosure, the accuracy of estimating the internal state of a chamber can be improved by estimating the internal state of the chamber.

[0011] According to the present disclosure, it is possible to estimate the internal state of an accurate chamber even with a relatively small number of reference state data.

[0012] The effects of the invention of the present application are not limited to the effects described above, and effects not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present application belongs from the present application.

[0013] FIG. 1 is a block diagram of a monitoring device according to one embodiment.

[0014] Figures 2 and 3 are schematic diagrams of a monitoring device installed in a chamber according to one embodiment.

[0015] Figure 4 is a graph of the S11 parameter, which is an example of state data.

[0016] FIG. 5 is a method for generating reference state data according to one embodiment of the present disclosure.

[0017] FIG. 6 relates to a method for calculating the similarity between reference state data and state data and a method for estimating the internal state of a chamber based thereon.

[0018] Figure 7 is intended to explain a problem in the method for estimating the internal state of the chamber described in Figure 6.

[0019] FIGS. 8 to 19 are for explaining a method for improving the estimation accuracy of the internal state of a chamber according to an embodiment of the present disclosure.

[0020] FIGS. 20 and 21 are for explaining a method of performing interpolation and extrapolation according to an embodiment of the present disclosure.

[0021] FIGS. 22 and 23 are drawings showing that the estimation accuracy increases when the dimension of the coordinate system is increased according to an embodiment of the present disclosure.

[0022] Figure 24 is a block diagram of a monitoring system according to one embodiment.

[0023] Figure 25 is a schematic diagram of a monitoring system installed in process equipment according to one embodiment.

[0024] Since the embodiments described in this disclosure are intended to clearly explain the spirit of the present disclosure to a person having ordinary skill in the art to which the present disclosure pertains, the present disclosure is not limited to the embodiments described in this disclosure, and the scope of the present disclosure should be interpreted to include modified or altered examples that do not depart from the spirit of the present disclosure.

[0025] The terms used in this disclosure have been selected from widely used, common terms, taking into account the functions of this disclosure. However, these terms may vary depending on the intentions of those skilled in the art, customs, or the emergence of new technologies. However, if a specific term is defined and used with an arbitrary meaning, the meaning of that term will be described separately. Therefore, the terms used in this disclosure should be interpreted based on the actual meaning of the term and the overall content of this disclosure, rather than simply the name of the term.

[0026] The drawings of the present disclosure are intended to facilitate explanation of the present disclosure, and shapes depicted in the drawings may be exaggerated as necessary to aid understanding of the present disclosure, and thus the present disclosure is not limited by the drawings.

[0027] In the present disclosure, if a detailed description of the configuration or function of a notice related to the present disclosure is deemed to obscure the gist of the present disclosure, a detailed description thereof will be omitted as necessary. Furthermore, unless otherwise specified, numbers (e.g., "first," "second," etc.) used in the description of the present disclosure are merely identifiers used to distinguish one component from another.

[0028]

[0029] According to the present disclosure, a monitoring device can be provided. The monitoring device can transmit radio waves into a chamber of process equipment, such as semiconductor process equipment or display process equipment, and receive radio waves reflected from the chamber, thereby monitoring the geometrical state and / or electrical / physical characteristics of the chamber. More specifically, the chamber includes a plurality of parts, such as a lower electrode on which a substrate, such as a wafer, is placed, an upper electrode facing the lower electrode, pins for supporting the substrate, and a baffle, and the geometrical state of the chamber can be defined by a combination of the geometrical states of each part, such as the position or shape.

[0030] Even when the same radio wave is transmitted into the chamber, the received radio wave may differ depending on the geometrical state of the chamber. For example, if the geometrical state of some parts is changed, such as by changing the position or shape of some parts, even when the same radio wave is transmitted into the chamber, the radio wave received after the change may differ from the radio wave received before the change. In other words, the way the radio wave is reflected inside the chamber may vary depending on the geometrical state of the chamber. In other words, the received reflected wave may reflect the geometrical state of the chamber.

[0031] Alternatively, as plasma is generated within the chamber, the load within the chamber may change, or as process cycles progress within the chamber, the environment within the chamber may change according to each process. In this case, a monitoring device can monitor the electrical / physical characteristics of the chamber according to the changing load or environment within the chamber.

[0032] For example, as a process progresses within a process chamber, the environment within the chamber may change due to changes in the temperature, height, and position of the wafer chuck. In such cases, even if the same radio wave is transmitted into the chamber, the radio wave received after the change may differ from the radio wave received before the change. In other words, the way the radio wave is reflected within the chamber may vary depending on the physical and electrical conditions of the chamber. In other words, the received reflected wave may reflect the physical and electrical conditions of the chamber.

[0033] Additionally, the monitoring device can monitor chambers that are not undergoing a process (as well as chambers undergoing a process). For example, the monitoring device can monitor chambers that are not undergoing a process, such as by monitoring the geometrical condition inside the chamber to determine the assembly status of process equipment during manufacturing of the process equipment or to determine the results after preventive maintenance (PM) of the process equipment. For another example, the monitoring device can monitor chambers undergoing a process, such as by monitoring the geometrical condition inside the chamber to determine whether the process is proceeding normally at each process step or to predict the timing of preventive maintenance. As another example, the monitoring device can monitor the electrical / physical characteristics inside the chamber to determine whether each process is operating normally.

[0034] The monitoring target of the device and method for monitoring the state of the chamber disclosed by the present disclosure is, as described above, whether the equipment is properly assembled before the process is performed, or whether there is any abnormality in the state of the equipment between and during the process. That is, the target to be monitored by the device and method disclosed by the present disclosure may include the geometric shape of each part inside the chamber, a level of wear-out of each part, a relative positional relationship between each part, unnecessary deposition of by-products generated by the process for the target substrate through the chamber on the inner wall of the chamber and on the surface of each part inside the chamber, etc.

[0035] In addition, the object to be monitored by the device and method disclosed by the present disclosure may include the state of materials and energy supplied into the chamber to be monitored (e.g., active species, etching gas, inert gas, RF power, or plasma thereof introduced into the chamber to perform a required process, etc.).

[0036]

[0037] A method for estimating a state of a chamber according to an embodiment of the present disclosure, wherein a chamber monitoring device obtains Y reference state data corresponding to Y coordinates within an N-dimensional coordinate system having M elements as axes, wherein Y is a natural number greater than or equal to 2 and is a part of all coordinates that can be expressed in the N-dimensional coordinate system, and the N elements are selected from among M elements defining the state of the chamber, M is a natural number greater than or equal to 1, N is a natural number greater than or equal to 1, and M is greater than or equal to N; transmits radio waves of a specific frequency range into the chamber and receives radio waves reflected from the interior of the chamber; generates current state data representing the state of the chamber based on the received radio waves; calculates a similarity between each of the Y reference state data and the current state data to determine Y first state similarities; The method may include: generating Y first state similarity data by mapping the Y first state similarities and the Y coordinates; determining a plurality of second state similarity data for the entire coordinates by performing at least one of interpolation and extrapolation within the N-dimensional coordinate system based on the Y first state similarity data, wherein each of the plurality of second state similarity data includes a second state similarity for each of the entire coordinates; determining second state similarity data corresponding to a second state similarity having a maximum value among the second state similarities included in the plurality of second state similarity data as estimated state similarity data; and estimating a current state of each of the N elements according to the coordinates included in the estimated state similarity data.

[0038] At this time, obtaining the Y reference state data includes performing a first operation for each of the Y coordinates to obtain the Y reference state data, and the first operation may include: artificially adjusting the N elements to a value corresponding to one of the Y coordinates; transmitting radio waves of the specific frequency range into the interior of the chamber and receiving radio waves reflected from the interior of the chamber; and generating reference state data indicating the state of the chamber based on the received radio waves.

[0039] Additionally, among the above M elements, the remaining elements excluding the above N elements may not be artificially adjusted.

[0040] Additionally, the plurality of second state similarities may be determined by determining the similarity between the state of the chamber and the current state data when the N elements have values ​​corresponding to any one of the overall coordinates.

[0041] In addition, estimating the plurality of second state similarity data includes performing at least one of the interpolation and the extrapolation using a function of dimension Z or more, wherein Z may be an integer greater than or equal to 0.

[0042] Additionally, the Y coordinates may be selected such that the spacing between adjacent coordinates within the N-dimensional coordinate system is constant.

[0043] Additionally, the Y coordinates can be arbitrarily selected within the N-dimensional coordinate system.

[0044] Additionally, the Y coordinates can be selected according to a preset pattern within the N-dimensional coordinate system.

[0045] In addition, the above N is a natural number greater than or equal to 2, and the N elements can be selected to have a relationship in which, when the value of one element among the N elements changes at a first ratio, the value of at least one of the remaining elements changes by exceeding a second ratio.

[0046] A chamber monitoring device for estimating a state of a chamber according to the present disclosure may include: an antenna for transmitting radio waves of a specific frequency range into the interior of the chamber and receiving radio waves reflected from the interior of the chamber; a bracket for fixing the antenna to the interior or exterior of the chamber; a signal processor for applying an electric signal to the antenna and obtaining an electric signal from the antenna; and a controller for controlling the signal processor and generating state data of the chamber based on the electric signal obtained by the signal processor.

[0047] At this time, the controller obtains Y reference state data corresponding to Y coordinates in an N-dimensional coordinate system with N elements as axes, wherein Y is a natural number greater than or equal to 2 and is a part of all coordinates that can be expressed in the N-dimensional coordinate system, and the N elements are selected from M elements defining the state of the chamber, M is a natural number greater than or equal to 1, N is a natural number greater than or equal to 1, and M is greater than or equal to N; controls the signal processor so that the antenna transmits a radio wave of a specific frequency range into the interior of the chamber and receives a radio wave reflected from the interior of the chamber, thereby controlling the signal processor to obtain an electrical signal according to the received radio wave; generates current state data representing the state of the chamber based on the received radio wave; calculates a similarity between each of the Y reference state data and the current state data to determine Y first state similarities; maps the Y first state similarities and the Y coordinates to generate Y first state similarity data; The method may further include: determining second state similarity data for the entire coordinates by performing at least one of interpolation and extrapolation within the N-dimensional coordinate system based on the Y first state similarity data, wherein each of the plurality of second state similarity data includes a second state similarity for each of the entire coordinates; determining second state similarity data corresponding to a second state similarity having a maximum value among second state similarities included in the plurality of second state similarity data as estimated state similarity data; and estimating a current state of each of the N elements according to a coordinate included in the estimated state similarity data.

[0048] In addition, the controller may perform a first operation for each of the Y coordinates to obtain the Y reference state data, the first operation artificially adjusting the N elements to a value corresponding to one of the Y coordinates; controlling the signal processor to transmit radio waves of the specific frequency range to the inside of the chamber by the antenna and receive radio waves reflected from the inside of the chamber, thereby obtaining an electrical signal according to the received radio waves; and generating reference state data representing the state of the chamber based on the received radio waves.

[0049] Additionally, among the above M elements, the remaining elements excluding the above N elements may not be artificially adjusted.

[0050] Additionally, the second state similarities may be determined by determining the similarity between the state of the chamber and the current state data when the N elements have values ​​corresponding to any one of the overall coordinates.

[0051] Additionally, the controller performs at least one of the interpolation and the extrapolation using a function of dimension Z or more, wherein Z may be an integer greater than or equal to 0.

[0052] Additionally, the Y coordinates may be selected such that the spacing between adjacent coordinates within the N-dimensional coordinate system is constant.

[0053] Additionally, the Y coordinates can be randomly selected within the N-dimensional coordinate system.

[0054] Additionally, the Y coordinates can be selected according to a preset pattern within the N-dimensional coordinate system.

[0055] In addition, the above N is a natural number greater than or equal to 2, and the N elements can be selected to have a relationship in which, when the value of one element among the N elements changes at a first ratio, the value of at least one of the remaining elements changes by exceeding a second ratio.

[0056]

[0057] [Definitions of terms used in this disclosure]

[0058] Meanwhile, in describing embodiments of the present disclosure, terms used may be defined as follows.

[0059] (1) Status data

[0060] It can be a set of parameters reflecting the geometrical state, electrical state and / or physical state inside the chamber. For example, the parameters that can be utilized as state data can be i) S-parameters, ii) H-parameters, iii) Y-parameters, iv) Z-parameters, v) a combination of at least two parameters selected from the S-parameters, H-parameters, Y-parameters and Z-parameters, vi) parameters derived from the S-parameters, H-parameters, Y-parameters and Z-parameters, or vii) parameters derived from a combination of at least two parameters selected from the S-parameters, H-parameters, Y-parameters and Z-parameters. The monitoring device can measure the frequency characteristics inside the chamber to derive a set of parameters, and determine the internal state of the chamber using the sets of parameters.

[0061] (2) Element

[0062] As used herein, the term "element" may be an element that defines a geometric state, an electrical state, and / or a physical state within a chamber. In other words, it may mean an element that can change a state within a chamber. For example, elements that can change an electrical state and / or a physical state within a chamber and define an electrical state and / or a physical state within a chamber may include a wafer chuck height, a wafer chuck temperature, a chamber wall temperature, an edge ring height, a gate valve position, a flow rate and pressure of a gas supplied into the chamber, a radio frequency (RF) power and RF frequency provided to the chamber, a wafer chuck DC bias voltage, a slot valve position, a wafer loading degree, a thickness of a byproduct deposition on an inner wall of the chamber, and the like.

[0063] In addition, for example, elements that can change the geometric state inside the chamber and define the geometric state inside the chamber may include the positions and shapes of multiple parts, such as a lower electrode on which a substrate such as a wafer is placed, an upper electrode facing the lower electrode, pins for supporting the substrate, and baffles, as described above.

[0064] (3) Coordinate system

[0065] As described below, the monitoring device and / or the monitoring system can select N elements, which are at least some of the M elements that can define the internal state of the chamber. At this time, the monitoring device or the monitoring system can form a virtual coordinate system with each of the N elements as an axis. That is, in the present disclosure, the coordinate system means a virtual coordinate system having N axes with each of the N selected elements as an axis. Therefore, the dimension of the coordinate system can be N-dimensional. For example, if only one element out of the M elements is selected, the coordinate system is a one-dimensional coordinate system and has only one axis. As another example, if two elements out of the M elements are selected, the coordinate system can be a two-dimensional coordinate system and have two axes.

[0066] However, since this coordinate system is a virtual coordinate system, it does not necessarily have to be visually represented. That is, in the present disclosure, the coordinate system is defined to explain the concept of the present disclosure, and for example, the monitoring device and / or monitoring system can map each axis of the coordinate system and the coordinates of each coordinate system and store them in a table format. In addition, as another example, the monitoring device and / or monitoring system can map elements indicating each axis of the coordinate system and the coordinates of each coordinate system and store them in a listed format.

[0067] In other words, the coordinate system in the present disclosure is not a coordinate system in which N axes of each of N elements are necessarily orthogonal, and any form in which N elements and the values ​​of the N elements are mapped to each other can be referred to as a coordinate system.

[0068] (4) Coordinates

[0069] Coordinates can mean a set of values ​​for each of the N selected elements. For example, N1, N 2,If N3, N4, and N5 are selected to form a five-dimensional coordinate system, the coordinates can be expressed as (V1, V2, V3, V4, V5). At this time, V1 is a value on the N1 axis, V2 is a value on the N2 axis, V3 is a value on the N3 axis, V4 is a value on the N4 axis, and V5 can be a value on the N5 axis.

[0070] In other words, just as a coordinate system need not necessarily be visually expressible, coordinates should not be interpreted as being limited to specific points that can be pointed to in an N-dimensional space. In other words, coordinates should be interpreted as a set of values ​​corresponding to each axis within the coordinate system.

[0071] (5) State similarity data

[0072] In the present disclosure, state similarity data includes coordinates and state similarity. The state similarity is calculated by measuring the similarity between reference state data and current state data. Furthermore, the coordinates are coordinates of the reference state data used to calculate the similarity, and are a set of values ​​of elements adjusted when generating the reference state data. In other words, the state similarity data contains information about the similarity between the internal state of the chamber at the corresponding coordinates and the internal state of the current chamber.

[0073]

[0074] [Monitoring device according to an embodiment of the present disclosure]

[0075] Fig. 1 is a block diagram of a monitoring device according to one embodiment. Referring to Fig. 1, the monitoring device (100) may include an antenna (110), a signal processing unit (120), a communication unit (130), a control unit (140), and a storage unit (150).

[0076]

[0077] The monitoring device (100) can transmit and receive radio waves through the antenna (110). The antenna (110) can receive an electrical signal and transmit the radio waves. The antenna (110) can receive the radio waves and convert them into electrical signals. The monitoring device (100) may include one antenna (110). Alternatively, the monitoring device (100) may include two or more antennas (110). In this case, some of the two or more antennas (110) may be for transmitting radio waves, and the rest may be for receiving radio waves. Alternatively, each of the two or more antennas (110) may be for transmitting and receiving radio waves at different locations.

[0078] The monitoring device (100) can apply an electric signal to the antenna (110) through the signal processing unit (120) and obtain an electric signal from the antenna (110). The signal processing unit (120) can apply an electric signal of a specific frequency range to the antenna (110). The signal processing unit (120) can obtain an electric signal of a specific frequency range from the antenna (110). The signal processing unit (120) can control the frequency and amplitude of a radio wave to be output through the antenna (110) and sense information about the frequency and amplitude of a radio wave received through the antenna (110). More specific details about this will be described later.

[0079] The monitoring device (100) can generate status data through a signal processing unit (120). More specific details about this will be described later.

[0080] The monitoring device (100) can communicate with the outside world through the communication unit (130). For example, the communication unit (130) can transmit status data, monitoring information, etc. to the outside world.

[0081] The communication unit (130) can perform wired or wireless communication. The communication unit (130) may be, for example, a wired / wireless local area network (LAN) module, a WAN module, an Ethernet module, a Bluetooth module, a Zigbee module, a USB (Universal Serial Bus) module, an IEEE 1394 module, a Wi-Fi module, an EtherCAT module, a DeviceNet module, or a combination thereof, but is not limited thereto.

[0082] The monitoring device (100) can generate monitoring information through the control unit (140). The control unit (140) can generate monitoring information based on status data. More specific details regarding this will be described later.

[0083] The control unit (140) may be implemented as a computer or a similar device using hardware, software, or a combination thereof. In terms of hardware, the control unit (140) may be one or more processors. Alternatively, the control unit (140) may be provided as processors that are physically separated and cooperate through communication. Examples of the control unit (140) include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), a state machine, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a radio-frequency integrated circuit (RFIC), or a combination thereof. In terms of software, the control unit (140) may be provided in the form of a program that drives the hardware control unit (140).

[0084] Meanwhile, the operations of all embodiments described in the present disclosure may be controlled and executed by the control unit (140). For example, operations including at least one of Embodiments 1 to 5 described in the present disclosure may be executed under the control of the control unit (140). In other words, the control unit (140) may control the overall operation of the monitoring device (100).

[0085] The monitoring device (100) can store various data and programs in the storage unit (150). For example, the storage unit (150) can store status data generated by the signal processing unit (120). As another example, the storage unit (150) can store monitoring information generated by the control unit (140).

[0086] The storage unit (150) may be, for example, a nonvolatile semiconductor memory, a hard disk, a flash memory, an SSD (Solid State Drive), a RAM (Random Access Memory), a ROM (Read Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), or other types of (tangible) nonvolatile recording media or a combination thereof, but is not limited thereto.

[0087] The monitoring device (100) may further include a fixing member (160). The fixing member (160) may fix the antenna (110) to a position around the chamber. For example, the fixing member (160) may fix the antenna (110) so that the antenna (110) and the chamber have a predetermined distance. The predetermined distance may be, for example, 1 mm, 3 mm, 5 mm, 7 mm, or 1 cm, but is not limited thereto. For another example, the fixing member (160) may fix the antenna (110) so that the antenna (110) and the chamber come into contact with each other. The fixing member (160) may be, for example, a bracket, but is not limited thereto.

[0088] The monitoring device (100) may further include an output unit (170). For example, the output unit (170) may be a display. The monitoring device (100) may display monitoring information through the display. As another example, the output unit (170) may be a speaker. The monitoring device (100) may output an alarm through the speaker.

[0089] The monitoring device (100) may further include an electromagnetic wave shield (180). The electromagnetic wave shield (180) prevents or reduces the influence of external electromagnetic waves on the antenna (110). For example, the electromagnetic wave shield (180) may be placed outside the chamber to surround the antenna (110). The electromagnetic wave shield (180) may be provided with various materials capable of shielding electromagnetic waves.

[0090] The monitoring device (100) may be provided in an integrated form. For example, the monitoring device (100) may be provided in an integrated form with an antenna (110), a signal processing unit (120), a communication unit (130), a control unit (140), a storage unit (150), and a fixing unit (160).

[0091] Alternatively, the monitoring device (100) may be provided in a separate form. For example, the monitoring device (100) may be provided in a form in which the antenna (110) and the remaining components are separated. A description of the integrated monitoring device and the separate monitoring device will be provided later with reference to FIG. 3.

[0092] Not all of the components illustrated in FIG. 1 are essential components of the monitoring device, and at least some of the components illustrated in FIG. 1 may be omitted. In addition, the monitoring device may additionally include components not illustrated in FIG. 1.

[0093] The monitoring device can be implemented using a network analyzer such as a vector network analyzer (VNA).

[0094] For example, the signal processing unit, communication unit, control unit, and storage unit can be implemented using a network analyzer.

[0095] For another example, the signal processing unit may be implemented using a network analyzer. In this case, the monitoring device may include separate devices for implementing a communication unit, control unit, and storage unit in addition to the network analyzer.

[0096]

[0097] Monitoring devices can be installed in the chamber.

[0098] Figures 2 and 3 are schematic diagrams of a monitoring device installed in a chamber according to one embodiment.

[0099] Referring to FIG. 2, the antenna may be located outside the chamber (10). For example, the antenna may be located outside the viewport (11) formed in the chamber (10).

[0100]

[0101] The antenna may be installed outside the chamber (10) by a fixing member. For example, the antenna may be installed outside the chamber (10) by a fixing member so as to have a predetermined distance from the chamber (10). For another example, the antenna may be installed outside the chamber (10) by a fixing member so as to be in contact with the chamber (10).

[0102] Although not shown, the antenna may be located inside the chamber. For example, the antenna may be located inside a viewport formed in the chamber. The antenna may be installed inside the chamber by a fixing member. However, if the antenna is located inside the chamber, problems such as contamination of the chamber by the antenna or contamination of the antenna during the process may occur, which may be disadvantageous compared to when the antenna is located outside the chamber.

[0103] Referring to FIG. 3, in the case of an integrated monitoring device (100), the monitoring device (100) may be used in a form in which it is mounted in a chamber (10). For example, this may mean that all components of the monitoring device (100) are created to be non-detachable, so that the entire monitoring device (100) is attached to the outside of the chamber.

[0104] In the case of a detachable monitoring device, the monitoring device may be used in a form where only some of its components are mounted in a chamber, and the remaining components are connected to the components mounted in the chamber via wires. For example, the monitoring device may be used in a form where the antenna is mounted in the chamber, and the remaining components are connected to the antenna via wires. The connecting wires may be, for example, coaxial cables. For example, in the case of a detachable monitoring device, only some of the components (e.g., the antenna) may be attached to the outside of the chamber, and the remaining components may be separated from some of the components and connected to some of the components via wires or wirelessly. In other words, in the case of a detachable monitoring device, it may mean that at least some of the components of the monitoring device are designed to be detachable, and each component is designed to be assembled depending on the purpose of use.

[0105] Here, "assembleable" may mean that some components are assembled so that they are directly connected to the rest of the components without connecting wires, such as coaxial cables. Furthermore, as described above, some components may be connected to the rest of the components via wires, or they may be connected wirelessly. For example, if some components are connected wirelessly to the rest of the components, each of the components may further include a wireless communication unit for wireless communication.

[0106] Although FIGS. 2 and 3 illustrate that the antenna is positioned relative to the viewport, the antenna may also be positioned relative to a region of the chamber that is permeable to radio waves, such as ceramic, in addition to the viewport. For example, a separate port for mounting the antenna may be formed in the chamber in addition to the existing viewport, and the antenna may be positioned relative to the separate port.

[0107] Additionally, although the monitoring device is described as including one antenna in FIGS. 2 and 3, as described above, the monitoring device may include two or more antennas. In this case, some of the two or more antennas may be mounted in one area of ​​the chamber, and the rest may be mounted in another area of ​​the chamber.

[0108]

[0109] [How the monitoring device generates status data]

[0110] Monitoring devices can generate status data.

[0111] The status data may be related to radio waves incident from the antenna into the chamber (hereinafter, "incident waves") and radio waves reflected from the chamber and received by the antenna (hereinafter, "reflected waves"). The status data may be related to a voltage applied to the antenna and a voltage output from the antenna.

[0112] Status data can correspond to a specific frequency range. Status data can be generated for a specific frequency range.

[0113] State data can be defined using incident and reflected waves. For example, state data can be defined using the ratio of incident and reflected waves, such as the ratio of reflected waves to incident waves. State data can be, for example, but is not limited to, S-parameters, H-parameters, Y-parameters, Z-parameters, or parameters that can be calculated therefrom.

[0114] In some embodiments, the state data may be S-parameters.

[0115]

[0116] *In some other embodiments, the state data may be H-parameters.

[0117] In some other embodiments, the state data may be a Y-parameter.

[0118] In some other embodiments, the state data may be Z-parameters.

[0119] In some other embodiments, the state data may be a parameter derived from at least one selected from an S-parameter, an H-parameter, a Y-parameter, and a Z-parameter.

[0120] Additionally, in some other embodiments, the state data may be a combination of at least two parameters selected from among S-parameters, H-parameters, Y-parameters and Z-parameters.

[0121] Additionally, in some other embodiments, the state data may be a parameter derived from a combination of at least two parameters selected from among S-parameters, H-parameters, Y-parameters and Z-parameters.

[0122] That is, the state data may be i) an S-parameter, ii) an H-parameter, iii) a Y-parameter, iv) a Z-parameter, v) a combination of at least two parameters selected from an S-parameter, an H-parameter, a Y-parameter and a Z-parameter, vi) a parameter derived from an S-parameter, an H-parameter, a Y-parameter and a Z-parameter, or vii) a parameter derived from a combination of at least two parameters selected from an S-parameter, an H-parameter, a Y-parameter and a Z-parameter.

[0123] For example, state data can be represented as an n X 2 matrix as follows:

[0124] (1st frequency) (magnitude of reflected wave / magnitude of incident wave)

[0125] (second frequency) (magnitude of reflected wave / magnitude of incident wave)

[0126] ...

[0127] (nth frequency) (magnitude of reflected wave / magnitude of incident wave)

[0128] As another example, state data can be represented as an n X 3 matrix as follows:

[0129] (1st frequency) (magnitude of incident wave) (magnitude of reflected wave)

[0130] (second frequency) (magnitude of incident wave) (magnitude of reflected wave)

[0131] ...

[0132] (nth frequency) (magnitude of incident wave) (magnitude of reflected wave)

[0133] Here, n is the number of frequencies at which status data is measured, the first frequency is the lower limit of the frequency at which status data is measured, the nth frequency is the upper limit of the frequency at which status data is measured, and the first to nth frequencies are the frequency ranges at which status data is measured.

[0134] Meanwhile, when the monitoring device (100) measures status data, the status data can be measured by transmitting radio waves corresponding to each of the first to n-th frequencies at least once. For example, after measuring parameters while transmitting radio waves of the first frequency m times, the parameters can be measured while transmitting radio waves of the second frequency m times, and repeating this process. In this case, the parameters can be measured while transmitting radio waves of the n-th frequency m times. At this time, the intensity of the radio waves of the first to n-th frequencies during the m transmissions can be different or the same for each transmission.

[0135] As another example, parameters can be measured by transmitting once from the first frequency wave to the nth frequency wave, and then measuring the parameters by transmitting once again from the first frequency wave to the nth frequency wave, thereby measuring the parameters by transmitting m times from the first frequency wave to the nth frequency wave. In this case, the wave intensity of each transmitted frequency can be different or the same for each transmission.

[0136] Meanwhile, n here can be determined based on the resolution of the frequency to be measured, i.e., the interval between frequencies. For example, when measuring state data between 3 GHz and 8.5 GHz, if n is 55, frequency characteristics can be measured in 0.1 GHz increments. As another example, if n is 11, frequency characteristics can be measured in 0.5 GHz increments.

[0137] The status data may include parameter values ​​for a specific frequency range. In the above example, (magnitude of reflected wave / magnitude of incident wave), (magnitude of incident wave), (magnitude of reflected wave), etc. may be parameter values. The number of parameter values ​​included in the status data may be, for example, 500 or more, 1000 or more, 1500 or more, or 2000 or more, but is not limited thereto. The status data may include multiple state data belonging to a specific frequency range, and multiple peaks belonging to the specific frequency range. The number of peaks included in the status data may be, for example, 5, 10, 20, 50, or 100 or more, but is not limited thereto.

[0138] State data can correspond to a specific point in time. State data can be generated at a specific point in time. For example, a specific point in time could be a point in time when the process is not in progress, such as when assembly of process equipment is completed during equipment manufacturing or when preventive maintenance of process equipment is completed. Alternatively, a specific point in time could be a point in time when the process is in progress, such as at a specific process step.

[0139] Fig. 4 is a graph of the S11 parameter, which is an example of state data. Fig. 4 shows the S11 parameter in dB units for the frequency range from 3 GHz to 8.5 GHz. In Fig. 4, dozens of peaks can be seen, but the number of peaks may vary depending on the criteria for counting peaks. For example, in Fig. 4, peaks are used to distinguish characteristics of state data or to distinguish patterns of state data, and the criteria may vary depending on the purpose. For example, a peak may be defined as a value at which the radio intensity in dB in each frequency range is above a certain level, or may refer to a frequency at which the radio intensity of a previous frequency range increases or decreases by a certain level compared to the radio intensity of a current frequency range. In addition, a peak may refer to a frequency at which the radio intensity of a previous frequency range increases or decreases by a certain level compared to the radio intensity of a current frequency range (i.e., the slope of the graph) by a certain level.

[0140]

[0141] Status data can reflect the geometric state of the chamber. For example, if the geometric state of a part, such as its position or shape within the chamber, changes, the status data after the change may differ from the status data before the change. For another example, the status data when some parts are damaged may differ from the status data when they are not damaged. For another example, the status data when foreign matter is present within the chamber may differ from the status data when the foreign matter is not present.

[0142] Status data can also reflect the electrical and physical state of the chamber. For example, since conductivity, permittivity, and other factors vary depending on the material properties of the chamber or part, status data can reflect the electrical state of the chamber. For example, if a polymer film or other material is formed on the chamber's internal walls as the process progresses, the permittivity of the walls will change, and thus the status data can reflect the chamber's electrical state. Another example is that the position, height, and temperature of the wafer chuck change as the process progresses within the chamber, and thus the status data can reflect the chamber's physical state.

[0143] That is, the status data may change depending on the process status within the chamber as the process cycle repeats. For example, the status data measured in the first process state of the process cycle and the status data measured in the second process state may change as the process state changes, even if there is no change in the position or shape of the parts contained within the chamber.

[0144] In one embodiment, the monitoring device can generate status data by transmitting radio waves into the chamber at different frequencies within a specific frequency range and receiving radio waves reflected within the chamber. For example, the monitoring device can generate a first parameter value by transmitting a radio wave of a first frequency into the chamber and receiving the radio waves reflected within the chamber, and can generate a second parameter value by transmitting a radio wave of a second frequency into the chamber and receiving the radio waves reflected within the chamber. By performing this for all frequencies, the monitoring device can generate status data corresponding to a specific frequency range.

[0145]

[0146] [Example 1: Method for Generating Reference State Data]

[0147] To monitor a chamber, a chamber in a process state (e.g., an idle state) that serves as a reference for chamber monitoring may exist, and the chamber in the current process state may be monitored by comparing the chamber in the reference process state with the chamber in the current process state. In this way, the process state of the chamber that serves as a reference for chamber monitoring may be referred to as a reference state.

[0148] For example, the reference state may be the golden chamber state. As another example, the reference state may be the process state of a chamber of interest to the user. The chambers of interest to the user may be, for example, a chamber in a good assembly state, a chamber that has completed preventive maintenance, a chamber with good process results, a chamber in a defective state, a chamber in a state requiring preventive maintenance, or a chamber in an accident state. As another example, the process state of the chamber of interest to the user may mean a state in which at least one of the elements that can define the internal state of the chamber has been artificially manipulated by the user. For example, the internal state of a chamber may be arbitrarily created by the user artificially manipulating the wafer chuck temperature and wafer chuck height.

[0149] The monitoring device can generate state data of the chamber in reference state (hereinafter referred to as “reference state data”).

[0150] FIG. 5 is a flowchart of a method for generating reference state data according to one embodiment.

[0151] Referring to FIG. 5, the monitoring device (100) can select a specific element from among M elements that can define the interior of the chamber (S501). In addition, the internal state of the chamber can be artificially adjusted so that the specific element has a certain coordinate, thereby preparing a chamber with an artificially adjusted internal state (S503).

[0152] However, among the M elements, it may not necessarily be necessary to select only one specific element. For example, the monitoring device (100) may select at least some N elements (i.e., N is 1 or more) among the M elements, and may artificially adjust the internal state of the chamber to have certain coordinates for the N elements. However, to help understanding the explanation, the case where N = 1 will be described first, and an embodiment for the case where N > 1 will be described in detail later.

[0153] Meanwhile, if a specific selected element is artificially changed, the remaining (M-1) elements may also change. In other words, the M elements that can define the internal state of the chamber may not change completely independently. For example, if the temperature of the wafer chuck is artificially adjusted, the height of the wafer chuck may also change. However, this relationship between these elements can be ignored because the height of the wafer chuck naturally changes with the change in temperature of the wafer chuck. In other words, only the selected specific elements can be artificially adjusted, assuming that the values ​​or states of the remaining elements are fixed. This is because changes in the remaining elements caused by artificially changing the selected specific element will not hinder the generation of the reference state data, as even such changes will be reflected in the reference state data.

[0154] The monitoring device (100) can transmit radio waves of a specific frequency range into the interior of a chamber in a reference state and receive radio waves reflected from the interior of the chamber (S505).

[0155] The above specific frequency range can be determined in consideration of the characteristics of the monitoring target of the device and method for monitoring the process state of the chamber disclosed by the present disclosure.

[0156] For example, as described above, the monitoring target of the device and method for monitoring the process status of the chamber disclosed by the present disclosure is whether the equipment (chamber) is properly assembled before the process as described above, or whether there is an abnormality in the inner wall of the equipment or the surface of various parts arranged inside the equipment due to the process performed between processes and after the process is completed. That is, the target to be monitored by the device and method disclosed by the present disclosure may include the geometric shape of each part inside the chamber, a level of wear-out of each part, a relative positional relationship between each part, unnecessary deposition of by-products generated by the process for the target substrate through the chamber on the inner wall of the chamber and the surface of each part inside the chamber, etc. Accordingly, the range of the specific frequency used in the device and method disclosed by the present disclosure can be determined as a frequency band advantageous for monitoring the geometric shape of each part inside the chamber, the relative position between each part, the degree of wear of each part, or unnecessary deposition of byproducts generated by the process on the inner wall of the chamber and the surface of each part inside the chamber.

[0157] As another example, a specific frequency range can be determined as a frequency band that can measure the state of the supplied material and energy, depending on the state of the supplied material and energy. For example, when monitoring electrical / physical properties within a chamber by measuring frequency characteristics, the state of the supplied material and energy must be measured, and a frequency range in which the electrical / physical properties change according to the measured state must be selected. In other words, a specific frequency range can be determined as a frequency band that is affected by the state of the supplied material and energy.

[0158] According to some embodiments, the specific frequency range may be determined as a frequency band having a wavelength of 1 mm to 1000 mm. That is, the specific frequency range may be 300 MHz to 300 GHz.

[0159] According to some other embodiments, the specific frequency range may be determined as a frequency band having a wavelength of 10 mm to 500 mm. That is, the specific frequency range may be 600 MHz to 30 GHz.

[0160] According to some other embodiments, the specific frequency range may be from 1 GHz to 20 GHz.

[0161] A specific frequency range may depend on the size of the space inside the chamber and / or the size of the parts contained within the chamber.

[0162] The lower limit of a specific frequency range may depend on the size of the chamber interior space. For example, the larger the chamber interior space, the smaller the lower limit may be.

[0163] The upper limit of a particular frequency range may depend on the size of the parts contained within the chamber. For example, the smaller the part, the higher the upper limit may be.

[0164] The monitoring device (100) can generate reference state data of the chamber using the received radio waves (S507). For example, the monitoring device (100) can generate reference state data by performing S505 to S507 once. As another example, the monitoring device (100) can maintain the coordinates of the selected specific element constant, perform S505 to S507 a preset number of times, secure a preset number of state data, and then generate reference state data by using representative values ​​(e.g., mean value, deviation value, standard deviation value, mode, median value, etc.) of the preset number of state data. Meanwhile, if the state data is a set of measurement parameters for each frequency, such as the S11 parameter, the monitoring device (100) can calculate representative values ​​(e.g., mean value, deviation value, standard deviation value, mode, median value) of each measurement parameter and set the reference state data by using the set of calculated measurement parameters.

[0165] In other words, one reference state data may be obtained by performing S505 to S507 one or more times in a situation where the coordinates of a specific element selected to generate one reference state data are constant. Therefore, generating one reference state data by performing S505 to S507 once should be understood as the monitoring device (100) transmitting radio waves of a specific frequency range into the chamber one or more times in a situation where the coordinates of a specific element selected are constant, receiving radio waves reflected from the inside of the chamber one or more times, and generating reference state data using the radio waves received one or more times.

[0166] Additionally, reference state data refers to data obtained by performing S505 to S507 described above one or more times, or data obtained by mapping the representative value of state data and the coordinates of a selected specific element. That is, the monitoring device (100) can generate one reference state data by mapping the representative value of state data obtained by performing S505 to S507 one or more times, or the coordinates of a selected specific element.

[0167] The monitoring device (100) can determine whether Y pieces of reference state data have been acquired (S509). At this time, Y pieces may be a preset number. If Y pieces of reference state data have not been acquired, the coordinates of the selected specific element can be artificially adjusted (S511). Thereafter, the monitoring device (100) can perform steps S505 to S507. That is, if the monitoring device (100) performs S505 to S507 until Y pieces of reference state data are acquired and Y pieces of reference state data are acquired, the monitoring device (100) can store Y pieces of reference state data (S513).

[0168] At this time, the coordinates being artificially adjusted may be different from the coordinates before adjustment. For example, the coordinates selected in S511 may be coordinates that have not been selected since S501 was performed. In other words, the coordinates corresponding to each of the Y reference state data must all be different coordinates, and no coordinates must overlap.

[0169]

[0170] [Example 2: Method for Calculating Similarity Between Reference State Data and Current State Data]

[0171] The monitoring device (100) can calculate the similarity between the reference state data and the state data measured by the monitoring device (100). The higher the similarity, the more likely it is that the current internal state of the chamber is similar to the reference state. Alternatively, if the similarity exceeds a similarity threshold, the current internal state of the chamber can be understood or determined to be the reference state. In other words, the current internal state of the chamber can be determined by referring to the similarity.

[0172] In addition, the monitoring device (100) can generate monitoring information based on the calculated similarity. The monitoring information can include a scatter plot of status data against reference status data. The user can visually confirm the relationship between the reference status data and the status data through the scatter plot. For example, the scatter plot can be a grid representation of the similarity between the status data measured according to a predetermined period or a measurement trigger signal indicated to the monitoring device (100) and the reference status data, expressed as points. In other words, the scatter plot can be a graph representation of the similarity between the status data and the reference status data according to a predetermined period or a measurement trigger signal indicated to the monitoring device (100).

[0173] Monitoring information may include a history of the chamber's past occurrences of a reference condition. This history may include, but is not limited to, the date, time, and number of times the reference condition occurred.

[0174] Monitoring information may include a description of the reference state. The description may, for example, be a description of what process state the reference state represents, but is not limited thereto. It may also include various other information related to the reference state.

[0175]

[0176] Figure 6 illustrates a process for generating monitoring information according to an embodiment of the present disclosure. In the present disclosure, monitoring information may include information estimating the current internal state of a chamber. Therefore, in the present disclosure, estimating the current internal state of a chamber may mean that the monitoring device (100) generates monitoring information.

[0177] Referring to FIG. 6, the monitoring device (100) can obtain Y reference status data generated and stored in FIG. 5 by reading (Loading) (S601).

[0178] In addition, the monitoring device (100) can transmit radio waves of a specific frequency range into the interior of the chamber and receive radio waves reflected from the interior of the chamber (S603). In addition, the monitoring device (100) can generate current state data of the chamber using the received radio waves (S605). For example, the monitoring device (100) can generate current state data by performing S603 to S605 one or more times as described above. At this time, if the monitoring device (100) has repeatedly performed S603 to S605 a certain number of times as described above, the current state data can be generated using representative values ​​of a certain number of state data obtained by repeating the performance. Meanwhile, reference state data is data in which state data (or representative values ​​of state data) and coordinates are mapped and included, but current state data is data that includes state data (or representative values ​​of state data) and coordinates are not mapped. This is because the purpose of the present disclosure is to find coordinates corresponding to the current state data using reference state data.

[0179] The monitoring device (100) can calculate the similarity between each of Y reference state data and the current state data to calculate Y first state similarities.

[0180] Similarity can be calculated through, but is not limited to, a graph similarity algorithm such as average, sum of squares (SOS), cosine similarity, correlation integral technique, or convolution technique.

[0181] Below we describe some examples of calculating similarity.

[0182] As an example of calculating similarity, the monitoring device (100) can calculate similarity by utilizing the difference between reference state data and current state data within a specific frequency range. For example, referring to [Mathematical Formula 1] below, the monitoring device (100) can calculate similarity as the sum of the squares of the differences between the parameter values ​​of the reference state data and the parameter values ​​of the current state data within a specific frequency range.

[0183]

[0184] Here, S11 (reference state) is a parameter value of reference state data, S11 (current state) is a parameter value of current state data measured by the monitoring device (100), and W is the total number of data points.

[0185] As another example of calculating similarity, referring to [Mathematical Formula 2], the monitoring device (100) can calculate similarity using the cosine similarity between reference state data and current state data within a specific frequency range.

[0186]

[0187] Here, S11 (reference state) represents the parameter values ​​of the reference state data in vector form, and S11 (current state) represents the parameter values ​​of the state data in vector form.

[0188] Meanwhile, if the above [Mathematical Formula 2] is expressed in the form of similarity %, it is as shown in [Mathematical Formula 3] below. In addition, [Mathematical Formula 3] also expresses the vector form of [Mathematical Formula 2] in the form of a scalar.

[0189]

[0190] The monitoring device (100) can generate Y pieces of first state similarity data based on Y pieces of first state similarity (S609). For example, the monitoring device (100) can generate Y pieces of first state similarity data by mapping Y pieces of first state similarity and coordinates corresponding to each of the Y pieces of first state similarity (S609).

[0191] The monitoring device (100) can estimate the current internal state of the chamber based on the first state similarity data (S611). In addition, the monitoring device (100) can generate the aforementioned monitoring information based on the estimated current internal state of the chamber and provide it to the user.

[0192] For example, the monitoring device (100) can estimate the coordinates of reference state data corresponding to the first state similarity having the maximum value among Y first state similarities as the current internal state of the chamber. In addition, the monitoring device (100) can generate monitoring information based on the estimated current internal state of the chamber and provide it to the user.

[0193]

[0194] [Example 3: Method 1 for increasing the estimation accuracy of the internal state of a chamber]

[0195] However, when the monitoring device (100) estimates the coordinates of the reference state data corresponding to the first state similarity having the maximum value among the Y first state similarities as the current internal state of the chamber, an error may occur in the estimation of the current internal state of the chamber.

[0196] FIG. 7 is a diagram for explaining a problem that occurs when estimating the coordinates of reference state data corresponding to the first state similarity having the maximum value as described above as the current internal state of the chamber.

[0197] Referring to FIG. 7, it is assumed that among M elements, "wafer chuck temperature" is selected and Y reference state data are acquired. For example, it shows that 9 reference state data are generated by artificially adjusting the "wafer chuck temperature" from 60 degrees to 100 degrees at 5-degree intervals. The monitoring device (100) can calculate the first state similarity between the current state data and each of the 9 reference state data. Referring to FIG. 7, the first state similarity at 80 degrees has the highest value of 99.592. Therefore, the monitoring device (100) can estimate that the temperature of the wafer chuck currently inside the chamber is 80 degrees. However, if the actual temperature of the wafer chuck currently inside the chamber is 77 degrees, there will be a difference from the temperature estimated by the monitoring device (100). That is, an estimation error may occur in estimating the internal state of the chamber using the above-described method.

[0198] Furthermore, since the above-described method acquires reference state data by artificially adjusting the coordinates of elements, even if numerous reference state data are acquired while finely adjusting the coordinates, there are bound to be other coordinates between the adjusted coordinates. In other words, no matter how finely coordinates are adjusted, there are bound to be coordinates that are not measured as reference state data between the coordinates.

[0199] Therefore, the above-described method inevitably introduces errors in estimating the current internal state of the chamber, making it impossible to always accurately estimate the current internal state of the chamber. Therefore, a method is needed to improve the accuracy of estimating the current internal state of the chamber.

[0200]

[0201] Figure 8 is a drawing for explaining a method for improving the estimation accuracy of the current internal state of the chamber.

[0202] Referring to Fig. 8, the monitoring device (100) can generate Y first state similarity data through S801 to S809. Meanwhile, the processes from S801 to S807 are identical to the processes from S601 to S609 of Fig. 6. Therefore, since the description is redundant, the detailed description of S801 to S807 will be omitted, and the description of S601 to S609 of Fig. 6 will be applied.

[0203] The monitoring device (100) can perform interpolation or extrapolation within the coordinate system based on Y pieces of first state similarity data (S811). At this time, the function used for interpolation or extrapolation can relatively increase accuracy if it is a polygonal function of the second or higher order. However, the function used for interpolation or extrapolation is not necessarily limited to a polygonal function of the second or higher order, and a zeroth or first order function may be used. For example, when a polygonal function is used, the accuracy may be high, but the amount of calculation for estimating state similarity in the entire coordinate system may become excessively large, and depending on the performance of the control unit (140) of the monitoring device (100), the excessive amount of calculation may cause a lot of time to be consumed in estimating state similarity.

[0204] For example, when the degree of a polynomial function is Z, Z can be an appropriate value that does not cause overfitting when performing interpolation or extrapolation. If the degree of the polynomial function is appropriately high, accurate interpolation or extrapolation can be performed, so that highly accurate state similarity can be measured for all coordinates within the coordinate system. However, if the degree of the polynomial function is excessively high, overfitting may occur, and the tendency between state similarities within the coordinate system may not reflect the actual internal state of the chamber according to all coordinates within the coordinate system.

[0205] Therefore, even if Z is chosen as a natural number greater than or equal to 2 rather than 0 or 1, it is important to choose an appropriate number that does not cause overfitting.

[0206] In summary, interpolation or extrapolation may be performed by applying a function with an appropriate order depending on the accuracy of the internal state estimation of the target chamber and the performance of the control unit (140).

[0207] At this time, an example that can be applied to performing interpolation or extrapolation is described in detail in [Example 5] described below.

[0208] The monitoring device (100) can determine a plurality of second state similarity data for each of the entire coordinates within the coordinate system by performing interpolation and / or extrapolation (S813). At this time, all of the second state similarity data for each of the entire coordinates within the coordinate system can also be estimated. That is, by performing interpolation and / or extrapolation, the value of the first state similarity included in the Y pieces of first state similarity data already generated can be changed. Alternatively, among the entire coordinates within the coordinate system, while maintaining the Y pieces of first state similarity data, state similarities for coordinates other than the Y pieces of coordinates can be estimated through interpolation and / or extrapolation.

[0209] Here, the global coordinates can refer to the numerous coordinates that can be expressed within the coordinate system. In other words, it can refer to the locations of all spaces included within the coordinate system divided into coordinate values.

[0210] The monitoring device (100) can select the state similarity data having the maximum similarity among a plurality of second state similarity data as the estimated similarity data (S815).

[0211] The monitoring device (100) can estimate the values ​​of the coordinates included in the estimated similarity data as the current internal state of the chamber (S817).

[0212] Fig. 9 shows an example of estimating the current internal state of the chamber using the same method as described above. In addition, in order to obtain the contour map of Fig. 9, among M elements, Y reference state data were acquired while artificially adjusting the wafer chuck temperature Y times. That is, the coordinate system of Fig. 9 is a one-dimensional coordinate system with the "wafer chuck temperature" as the axis, and the Y values ​​of the "wafer chuck temperature" artificially adjusted Y times become coordinates for the reference state data.

[0213] In addition, FIG. 9 shows that the monitoring device (100) calculates the similarity between each of the acquired Y reference state data and the current state data, generates Y first state similarity data, and obtains a plurality of second state similarity data for the entire coordinates through interpolation. The interpolation used in FIG. 9 visualizes a contour map for the state similarity data of "wafer chuck temperature" by applying a contour fitting method of a polynomial function.

[0214] Referring to FIGS. 9(a) and (b), it can be seen that the "wafer chuck temperature" is estimated to be 70 degrees regardless of the actual "wafer chuck height." Furthermore, regardless of whether reference state data was generated when the "wafer chuck temperature" was 70 degrees, if the current "wafer chuck temperature" is 70 degrees, the current "wafer chuck temperature" can be estimated to be 70 degrees through interpolation.

[0215] Therefore, the estimation accuracy can be increased by the embodiment of the present disclosure.

[0216] Furthermore, according to embodiments of the present disclosure, the current internal state of a chamber can be accurately estimated even with a small number of reference state data. Previously, to improve estimation accuracy, more reference state data had to be acquired for various coordinates. However, acquiring more reference state data required investing significantly more time and money to artificially adjust the coordinates. Furthermore, the user had to expend considerable effort to acquire the reference state data. Nevertheless, coordinates that could not be estimated with the reference state data were bound to arise, and therefore, the efficiency may not be significant compared to the time and cost invested.

[0217] Furthermore, storing numerous reference state data required corresponding storage space. Furthermore, estimating the internal state of the chamber required loading all reference state data each time, increasing the processing load for comparison with the current state data.

[0218] However, according to an embodiment of the present disclosure, even if relatively less reference state data is used, it is possible to achieve an effect of requiring less storage space and less processing load while enabling more accurate estimation of the current internal state of the chamber than when more reference state data is used.

[0219]

[0220] [Example 4: Method 2 for increasing the estimation accuracy of the internal state of a chamber]

[0221] Among M elements, one element is selected, and the selected element is artificially adjusted Y times so that the monitoring device (100) generates Y reference state data, as seen in [Example 2]. In addition, it was seen that generating Y reference state data according to the method of [Example 2] and estimating the current internal state of the chamber according to [Example 3] sufficiently increases the estimation accuracy compared to the conventional technique.

[0222] Nonetheless, in [Example 4], only one element is selected among M elements, and a monitoring device (100) generates Y reference state data, and based on this, a method is examined to increase the estimation accuracy more than estimating the current internal state of the chamber.

[0223] Figure 10 is intended to explain a problem that may arise when only one element among M elements is artificially adjusted Y times.

[0224]

[0225] *Figure 10 is a graph showing the state similarity between the reference state data and the current state data measured at coordinates where the wafer chuck height is 0.5 mm, measured multiple times. In other words, Figure 10 shows the state similarity measured multiple times to estimate the wafer chuck height inside the chamber. Also, although it is not a coordinate that constitutes the coordinate system, the temperature of the wafer chuck when the reference state data was generated was 100 degrees.

[0226] Looking at the graph in Figure 10, the similarity was highest when the current wafer chuck temperature was 100 degrees and the current wafer chuck height was 0.5 mm. This is a natural result, as the reference state data was generated when the wafer chuck temperature was 100 degrees and the wafer chuck height was 0.5 mm.

[0227] However, even though the reference state data was generated when the wafer chuck height was 0.5 mm, when the current wafer chuck temperature was 90 degrees, the similarity when the current wafer chuck height was 0.5 mm was not the highest. Specifically, when calculating the state similarity with the reference state data in the chamber internal state with the current wafer chuck temperature of 90 degrees, it was slightly higher when the current wafer chuck height was 0.6 mm than when it was 0.5 mm. Then, even though the actual current wafer chuck height is 0.6 mm, the wafer chuck height may be estimated to be 0.5 mm due to the change in the wafer chuck temperature. This results in a decrease in the estimation accuracy for the actually selected element due to changes in other unselected elements.

[0228] Also, as shown in Fig. 10, the similarities when the current wafer chuck height is 0.4 mm, 0.5 mm, and 0.6 mm are very similar. In this case, it may be ambiguous whether the monitoring device (100) should estimate the current wafer chuck height as 0.4 mm, 0.5 mm, or 0.6 mm.

[0229] Therefore, a method is needed to solve the problems in Fig. 10 described above and to further improve the estimation accuracy.

[0230] To solve the above-described problem and improve the estimation accuracy, N-dimensional reference state data can be secured. In this case, N can be a natural number greater than or equal to 2. That is, by selecting 2 or more elements from among M elements and generating Y reference state data, the estimation accuracy can be further improved. For example, if the monitoring device (100) generates reference state data while artificially adjusting not only the wafer chuck height but also the wafer chuck temperature in FIG. 10, a more accurate current internal state of the chamber can be estimated.

[0231] To this end, as mentioned in [Example 1], the method of generating reference state data described based on FIG. 5 in [Example 1] must be replaced with the method described in FIG. 11 to generate reference state data.

[0232] Referring to FIG. 11, the monitoring device (100) can select N elements among M elements that can define the interior of the chamber (S1101).

[0233] For example, when selecting two elements, if the purpose is to estimate the state of the wafer chuck, "wafer chuck height" and "wafer chuck temperature" can be selected. As another example, when selecting two elements, if the purpose is to estimate the degree of wafer alignment, "wafer loading degree" and "edge ring height" can be selected. As another example, when selecting two elements, if the purpose is to confirm whether the temperature inside the chamber has stabilized, "wafer chuck temperature" and "chamber wall temperature" can be selected. However, the present invention is not limited thereto, and the number of elements selected may be three or more, and various combinations of elements can be selected depending on the purpose of estimating the internal state of the chamber.

[0234] When N elements are selected from among M elements, the internal state of the chamber can be artificially adjusted so that the N elements have certain coordinates based on an N-dimensional coordinate system, thereby preparing a chamber with an artificially adjusted internal state (S1103).

[0235] Meanwhile, if N elements are artificially modified, the remaining (MN) elements may also change. However, as mentioned while explaining Figure 5 of [Example 1], the relationships between these elements can be ignored. In other words, even if the remaining (MN) elements change by artificially modifying N elements, this can be ignored.

[0236] The monitoring device (100) can transmit radio waves of a specific frequency range into the interior of a chamber in a reference state and receive radio waves reflected from the interior of the chamber (S1105).

[0237] In addition, the monitoring device (100) can generate reference state data of the chamber using the received radio waves (S1107). At this time, the method for generating one reference state data may be the same as that described in FIG. 5. In other words, one reference state data may be obtained by performing S1105 to S1107 one or more times in a situation where the coordinates of N elements selected to generate one reference state data are constant. Therefore, generating one reference state data by performing S1105 to S1107 once should be understood as the monitoring device (100) transmitting radio waves of a specific frequency range one or more times into the interior of the chamber in a situation where the coordinates of the selected specific element are constant, receiving radio waves reflected from the interior of the chamber one or more times, and generating reference state data using the radio waves received one or more times.

[0238] Additionally, the reference state data refers to data obtained by performing the above-described S1105 to S1107 one or more times, or data obtained by mapping the representative value of the state data and the coordinates of the selected specific element. That is, the monitoring device (100) can generate one reference state data by mapping the representative value of the state data obtained by performing S1105 to S1107 one or more times and the coordinates of the selected specific element. Here, the representative value may include, but is not limited to, the average value, the deviation value, the standard deviation value, the mode, the median, etc. as described above.

[0239] The monitoring device (100) can determine whether Y pieces of reference state data have been acquired (S1109). At this time, Y pieces may be a preset number. If Y pieces of reference state data have not been acquired, the coordinates of the selected specific element can be artificially adjusted (S1111). Thereafter, the monitoring device (100) can perform steps S1105 to S1107. That is, if the monitoring device (100) performs steps S1105 to S1107 until Y pieces of reference state data are acquired and Y pieces of reference state data are acquired, the monitoring device (100) can store Y pieces of reference state data (S1113).

[0240] At this time, the coordinates being artificially adjusted may be different from the coordinates before being adjusted. For example, the coordinates selected in S1111 may be coordinates that have not been selected since S1101 was performed. In other words, the coordinates corresponding to each of the Y reference state data must all be different coordinates, and no coordinates must overlap.

[0241] Meanwhile, when the coordinates for N elements are artificially adjusted, there may be various methods for selecting the coordinates to be artificially adjusted.

[0242] Fig. 12 illustrates an example of a method for selecting artificially adjusted coordinates when N is 2 and configuring Y reference state data accordingly. However, Fig. 12 is intended to facilitate easy understanding of the concept of the present disclosure by utilizing visual materials, and the methods for configuring Y reference state data described through Fig. 12 are not limited to the case where N=2.

[0243] In other words, it goes without saying that the method of configuring Y reference state data described through Figs. 12(a) to (d) can be applied even when N is 3 or more.

[0244]

[0245] *Now, with reference to Figure 12, let us examine how to configure Y reference state data.

[0246] Fig. 12(a) shows that Y reference state data are configured such that Y coordinates are all equally spaced across the N-dimensional coordinate system. Fig. 12(a) shows that the spacing between adjacent coordinates within the coordinate system may be constant. For example, the spacing between axially adjacent coordinates for the first element of Fig. 12(a) may be constant, and the spacing between axially adjacent coordinates for the second element may be constant.

[0247] The method of constructing Y reference state data, as shown in Fig. 12(a), is a method of obtaining Y reference state data by adjusting each of N elements selected as many times as possible within an N-dimensional coordinate system. Since each of N elements is adjusted as many times as possible, the estimation accuracy can also be higher than that of other construction methods.

[0248] At this time, estimation accuracy can be improved by increasing the spacing between elements. However, increasing the spacing between elements can also reduce the number of reference state data. Even with a reduced number of reference state data, estimation accuracy can be higher than with conventional techniques that do not perform interpolation, as described above.

[0249] Fig. 12(b) shows that Y reference state data are obtained by repeatedly performing the process of generating reference state data while adjusting the value of only one element among N selected elements at a constant interval while leaving the remaining elements unchanged for each of the N elements. As shown in Fig. 12(b), in the case of the reference state data measured while only the first element is changed and the second element is not changed, the interval between the adjacent coordinates in the axial direction for the first element is constant. On the other hand, in the case of the reference state data measured while only the second element is changed and the second element is not changed, the interval between the adjacent coordinates in the axial direction for the second element is constant.

[0250] Fig. 12(b) illustrates a method for constructing Y reference state data by adjusting only one of the N elements according to the value of greatest interest to the user for each of the N elements. A configuration as shown in Fig. 12(b) can significantly reduce the time cost for constructing Y reference state data.

[0251] Figure 12(c) illustrates the generation of reference state data for coordinates randomly selected within an N-dimensional coordinate system. Y coordinates are randomly selected, and the internal state of the chamber is artificially adjusted to correspond to each of the Y selected coordinates, thereby generating reference state data.

[0252] Even if Y reference state data are configured as in Fig. 12(c), if the Y reference state data are distributed across an N-dimensional coordinate system, it is sufficiently possible to estimate the current internal state of the chamber through interpolation.

[0253] Fig. 12(d) illustrates that coordinates are selected according to a preset pattern within an N-dimensional coordinate system, and the internal state of the chamber is artificially adjusted to correspond to each of the selected Y coordinates, so that reference state data can be generated. At this time, the preset pattern can be stored in the storage unit (150) of the monitoring device (100) and / or the storage unit (220) of the monitoring system described below. At this time, coordinates for the preset pattern can also be stored. Alternatively, when information on the preset pattern and reference coordinates is stored, Y coordinates can be selected by scaling the preset pattern according to the selected N elements, the size of the entire coordinate system, and the number of coordinates to be selected (i.e., Y).

[0254] Even in the case of Fig. 12(d), even if Y reference state data are configured, if the Y reference state data are distributed across the N-dimensional coordinate system, it is sufficiently possible to estimate the current internal state of the chamber through interpolation.

[0255] Meanwhile, the method of selecting Y coordinates and configuring Y reference state data is not limited to the examples of Fig. 12. That is, Fig. 12 is merely an example of a method for configuring Y reference state data, and the Y reference state data can be used in any way.

[0256] In addition, as described above, the examples of Fig. 12 are not limited to the case where N=2, and even when N>2, Y reference state data can be configured within an N-dimensional coordinate system using the same principle according to the increased number and direction of axes.

[0257] The monitoring device (100) can estimate the current internal state of the chamber using the Y pieces of stored reference state data. At this time, the monitoring device (100) can estimate the current internal state of the chamber according to the processes S801 to S817 described in FIG. 8. That is, when the number of selected elements increases, there is a difference in the method of configuring the Y pieces of reference state data, and the method of estimating the current internal state of the chamber using the Y pieces of reference state data may be the same.

[0258] That is, it can be seen that all coordinates of the coordinate system are the same except that they are coordinates of an N-dimensional coordinate system rather than coordinates of a one-dimensional coordinate system. That is, except that the number of values ​​included in the axes and coordinates of the coordinate system is N, processes S801 to S817 of FIG. 8 are also applied in [Example 4], so that the current internal state of the chamber can be estimated.

[0259] Figures 13 to 16 show the results of measuring the current internal state of the chamber using Y reference state data configured according to Figures 12(a) to (d) described above.

[0260] Figures 13 to 16 illustrate examples in which "wafer chuck height" and "wafer chuck temperature" are selected as heights for configuring Y reference state data. However, the present invention is not limited thereto, and it will be readily understood by those skilled in the art that the current internal state of the chamber can be measured according to the same principle even when other elements are selected, and that the current internal state of the chamber can be measured according to the same principle even when a number of elements greater than 2 is selected.

[0261] Additionally, the interpolation used in FIGS. 13 to 16 applies the contour fitting method of a polynomial function. Furthermore, a contour map is visualized for the state similarity data of "wafer chuck height" and "wafer chuck temperature."

[0262] Fig. 13 is an estimate of the current internal state of the chamber by configuring Y pieces of reference state data according to Fig. 12(a). Fig. 14 is an estimate of the current internal state of the chamber by configuring Y pieces of reference state data according to Fig. 12(b). Fig. 15 is an estimate of the current internal state of the chamber by configuring Y pieces of reference state data according to Fig. 12(c). Fig. 16 is an estimate of the current internal state of the chamber by configuring Y pieces of reference state data according to Fig. 12(d).

[0263] Referring to FIGS. 13 to 16, it is shown that not only the first state similarity data for the coordinates of Y pieces of reference state data, but also a plurality of second state similarity data for all coordinates within the coordinate system are produced through interpolation. That is, the second state similarity data for coordinates other than the Y coordinates of which the Y pieces of reference state data are composed can also be determined, and the highest state similarity data among the plurality of second state similarity data for all coordinates can be determined as the estimated state similarity data. In addition, the coordinates of the estimated state similarity data can be estimated as the current internal state of the chamber.

[0264]

[0265] Fig. 17 shows another method of configuring Y reference state data, and Fig. 18 shows an example of performing interpolation accordingly.

[0266] Figure 17 shows that Y reference state data are acquired while performing multiple processes included in one process cycle.

[0267] Fig. 17(a) shows that when a process cycle includes five processes from a to e, the monitoring device (100) acquires one reference state data from each of the five processes while performing the five processes. That is, the monitoring device (100) selects two elements from among the M elements defining the internal state of the chamber, and measures the coordinates of the two elements selected from each process while the process cycle is in progress.

[0268] Fig. 17(b) shows that the monitoring device (100) measures coordinates of two elements selected periodically or aperiodically within a single process. Meanwhile, Fig. 17(b) may show that the monitoring device (100) measures coordinates of two elements multiple times within a single process, but may also show that the monitoring device (100) measures coordinates of two elements within the same multiple processes performed while multiple process cycles are in progress. For example, the monitoring device (100) may measure coordinates of two elements each time the first process is performed while 10 process cycles are in progress. In this case, the monitoring device (100) may measure coordinates at least once in the first process of one process cycle.

[0269] Fig. 17(c) is a combination of Fig. 17(a) and Fig. 17(b), and may be obtained by measuring coordinates having two elements within multiple processes performed while multiple process cycles are in progress. For example, after measuring coordinates having two elements while multiple process cycles are in progress, the coordinates measured in each of the first to Tth processes may be classified based on process data.

[0270] Meanwhile, Figures 17(a) to 17(c) are merely examples for convenience of explanation and are not limited thereto. For example, the number of processes that can be included in a single process cycle is not limited to five, and a variety of processes can be included, allowing reference state data to be obtained for each process.

[0271] Fig. 18 shows the results of measuring the current internal state of the chamber using Y reference state data configured according to Fig. 17 described above.

[0272]

[0273] *Figure 18 illustrates an example in which “wafer chuck height” and “wafer chuck temperature” are selected as heights for configuring Y reference state data. However, it is not limited thereto, and it will be readily understood by those skilled in the art that the current internal state of the chamber can be measured according to the same principle even when other elements are selected, and that the current internal state of the chamber can be measured according to the same principle even when a number of elements greater than 2 is selected.

[0274] Additionally, the interpolation used in Figure 18 applies the contour fitting method of a polynomial function. Furthermore, a contour map is visualized for the state similarity data of "wafer chuck height" and "wafer chuck temperature."

[0275] Referring to FIG. 18, it is shown that not only the first state similarity data for the coordinates of Y pieces of reference state data, but also a plurality of second state similarity data for all coordinates within the coordinate system are produced through interpolation. That is, the second state similarity data for coordinates other than the Y coordinates of which the Y pieces of reference state data are composed can also be determined, and the state similarity data with the highest state similarity among the plurality of second state similarity data for all coordinates can be determined as the estimated state similarity data. In addition, the coordinates of the estimated state similarity data can be estimated as the current internal state of the chamber.

[0276] Meanwhile, when estimating the current internal state of the chamber according to FIGS. 17 and 18, it is possible to determine whether an abnormality has occurred during the process. For example, if there is a difference of a certain amount or more between the coordinates estimated as the current internal state of the chamber based on the current state data measured during the first process and the coordinates of the reference state data measured during the first process, the monitoring device (100) can recognize that an abnormality has occurred during the first process and can notify the user of this.

[0277] Meanwhile, as shown in FIG. 17, when performing multiple process cycles and obtaining reference state data for each of the multiple processes, obtaining the reference state data and estimating the current internal state of the chamber can be performed simultaneously.

[0278] For example, when the monitoring device (100) acquires current state data in the first process of the R-th process cycle, the current internal state of the chamber can be estimated using the reference state data and the current state data acquired up to the (R-1)th process cycle.

[0279] Meanwhile, in the first process of the R-th process cycle described above, the current state data can be added as reference state data to a database storing reference state data.

[0280] The monitoring device (100) can obtain current state data in the first process or the second process of the (R+1)th process cycle, and estimate the current internal state of the chamber by using the reference state data (i.e., the stored database) obtained up to the Rth process cycle and the current state data.

[0281] That is, the current state data measured in the Rth process cycle can be used as reference state data for estimating the current internal state of the chamber in the (R+1)th process cycle.

[0282] Meanwhile, if it is determined that there is an abnormality in the current internal state of the chamber based on the current state data measured in the Rth process cycle, the monitoring device (100) may not add the current state data measured in the Rth process cycle as reference state data. This may be because the current state data determined to be abnormal has low utility value as reference state data.

[0283]

[0284] Meanwhile, the current internal state of the chamber may be at coordinates outside the virtual coordinate system that served as the basis for determining the Y reference state data.

[0285] In such cases, extrapolation can be used to estimate the current internal state of the chamber. This will be discussed with reference to Figure 19.

[0286] Fig. 19 (a) shows that Y reference state data are configured according to a coordinate system corresponding to area A. However, when calculating the state similarity between the current state data and the Y reference state data, significant similarity may not be found within area A. Alternatively, when calculating the state similarity between the current state data and the Y reference state data and performing interpolation for area A, significant similarity may not be found. This may mean that there are no coordinates corresponding to the current internal state of the chamber within area A.

[0287] In such cases, the current internal state of the chamber can be estimated using extrapolation. Figures 19 (b) and (c) illustrate the estimation of the current internal state of the chamber using extrapolation. That is, if it is determined that no significant similarity can be found within region A, the coordinate system can be expanded using extrapolation.

[0288] For example, the monitoring device (100) can perform interpolation within the coordinate system of area A and select a coordinate having the maximum state similarity among a plurality of second state similarity data for all coordinates within the coordinate system.

[0289] The monitoring device (100) can determine whether the state similarity of the selected coordinates is significant enough to be estimated as the current internal state of the chamber. For example, the monitoring device (100) selects the coordinates with the maximum state similarity within the coordinate system. If the selected coordinates are located at the boundary of the area where interpolation is performed within the coordinate system, it can be estimated that the current internal state of the chamber exists outside the coordinate system, and there are no significant coordinates within the coordinate system that can be estimated as the current internal state of the chamber.

[0290] In this case, the monitoring device (100) can estimate that the current internal state of the chamber is in an area outside the coordinate system and perform extrapolation.

[0291] For example, referring to FIG. 20, in order to perform interpolation based on Y first state similarity data, (N+1) coordinates are connected. In other words, in FIG. 20, two elements are selected to generate first state similarity data for Y coordinates within a two-dimensional coordinate system, and by connecting three of the Y coordinates, multiple triangular shapes are generated across the entire coordinate system. At this time, the boundary of the area where interpolation is performed may mean the outermost lines among the lines that create multiple triangular shapes by connecting three of the Y coordinates, as indicated by the dotted line.

[0292] If, when the monitoring device (100) performs interpolation and selects a coordinate having the maximum state similarity, the selected maximum state similarity is located at the boundary, the monitoring device (100) estimates that the current internal state of the chamber is in an area outside the coordinate system, and can perform extrapolation.

[0293] To perform extrapolation, the monitoring device (100) can expand the coordinate system. For example, the coordinate system existing within area A can be expanded to a wider range. Within the expanded coordinate system, the monitoring device (100) can perform extrapolation to select the coordinates with the maximum state similarity within the expanded coordinate system. In addition, the monitoring device (100) can estimate the current internal state of the chamber based on the selected coordinates.

[0294] For example, Figs. 19(b) and (c) show examples of using extrapolation using a contour fitting method. The monitoring device (100) can estimate the current internal state of the chamber using extrapolation within the established coordinate system by expanding the coordinate system of area A. However, the extrapolation method does not have to use only the contour fitting method of Figs. 17(b) and (c), and any commonly known extrapolation method can be used.

[0295] Meanwhile, in step S811, the monitoring device (100) may perform extrapolation without performing interpolation. For example, if the monitoring device (100) determines that the current internal state of the chamber does not exist within the coordinate system of area A, the monitoring device (100) may perform extrapolation by expanding the coordinate system of area A without interpolation. At this time, if, among the state similarities of the first state similarity data of the Y coordinates of the coordinate system of area A, the coordinate having the maximum state similarity corresponds to the minimum or maximum value of the values ​​included in the Y coordinates, and is located at the outermost boundary of the area where interpolation was performed, the monitoring device (100) may perform extrapolation by expanding the coordinate system of area A, and estimate the current internal state of the chamber according to the coordinate having the maximum state similarity in the expanded coordinate system.

[0296] Meanwhile, the method of performing interpolation and extrapolation will be examined in detail in [Example 5].

[0297]

[0298] Meanwhile, [Example 4] was explained focusing on the case where N = 2, but as mentioned above, the above-described method can be applied equally to the case where N is 3 or more.

[0299] In addition, as N increases, the estimation accuracy increases, as described above, as the estimation accuracy increases when N = 2 compared to when N = 1. In addition, as N increases, the order of the function that can be used for interpolation or extrapolation can increase. That is, as N increases, the functions that can be used for interpolation and / or extrapolation can become more diverse. Through this, since interpolation and / or extrapolation can be performed using an appropriate function depending on the selected elements, the way in which the Y reference state data are configured, and / or the Y coordinates corresponding to the Y reference state data, the estimation accuracy for the current internal state of the chamber can be further increased.

[0300]

[0301] However, when four or more elements are selected among M elements, since the coordinate system must have four or more axes, it is difficult to visually represent the coordinates corresponding to the current internal state of the chamber within the coordinate system and the state similarity for all coordinates within the coordinate system, such as the contour maps expressed in FIGS. 13 to 17. Therefore, there may be limitations in providing the user with the state similarity for all coordinates and the coordinates corresponding to the current internal state of the chamber in a visual manner.

[0302] In this case, the monitoring device (100) can extract two to three elements from among four or more selected elements, and then generate one or more 2D coordinate system maps or 3D coordinate system maps for the two to three elements and provide them to the user. For example, if there are six selected elements and 2D coordinate system maps generated by extracting two elements each are provided to the user, the monitoring device (100) can combine 6C2 elements and generate 6C2 2D coordinate system maps for each of the combinations. In addition, at the user's request, the monitoring device (100) can provide at least some of the 6C2 2D coordinate system maps to the user.

[0303]

[0304] [Example 5: Interpolation and / or extrapolation method]

[0305] Now, let us describe a method for performing interpolation and / or extrapolation within the coordinate system described in S811 of FIG. 8.

[0306] When the monitoring device (100) determines the first state similarity data based on the first state similarity for each of the Y coordinates, interpolation and / or extrapolation can be performed using the Y coordinates and the first state similarity corresponding to each of the Y coordinates within the coordinate system.

[0307] (1) Interpolation

[0308] The monitoring device (100) selects (N+1) coordinates and connects them to each other. That is, if N elements are selected among M elements, the monitoring device (100) can select coordinates to have (N+1) vertices and connect them to each other.

[0309] At this time, the monitoring device (100) can select (N+1) coordinates and perform connecting them across the coordinate system. At this time, the monitoring device (100) must ensure that each of the Y coordinates is connected to another coordinate at least once. In other words, the monitoring device (100) must ensure that there is no coordinate among the Y coordinates that is not connected to another coordinate. This is because interpolation must be performed on all of the Y coordinates. In addition, the lines connecting the Y coordinates must not intersect.

[0310] Figure 20 shows an example of connecting Y coordinates to perform interpolation within a two-dimensional coordinate system.

[0311] Referring to Fig. 20, by selecting two elements, first state similarity data for Y coordinates within a two-dimensional coordinate system is generated, and by connecting the Y coordinates in groups of three, multiple triangle shapes are generated across the entire coordinate system.

[0312] Meanwhile, when selecting (N+1) Y coordinates and connecting them, the method for selecting (N+1) coordinates can be as follows.

[0313] (1) (N+1) coordinates can be arbitrarily selected. That is, the monitoring device (100) can arbitrarily select and connect (N+1) coordinates to be connected across the entire coordinate system. However, even in this case, the monitoring device (100) must select (N+1) coordinates so that the connected lines do not intersect.

[0314] (2) Coordinates having the greatest state similarity can be selected and connected. That is, the monitoring device (100) connects coordinates having the greatest state similarity, the second coordinate having the second greatest state similarity, and the third coordinate having the third greatest state similarity, thereby connecting coordinates having the greatest state similarity, so that Y coordinates can be connected throughout the coordinate system.

[0315] (3) Adjacent coordinates can be connected. That is, the monitoring device (100) can select and connect coordinates so that the distance between coordinates is the shortest, or the area of ​​the shape formed when connecting coordinates (e.g., a triangle shape in the case of a two-dimensional coordinate system) is the smallest. In this case, at least one coordinate selected first to connect the coordinates may be the coordinate at the farthest edge among the coordinates.

[0316] (4) (2) and (3) can be connected in a mixed manner. That is, the monitoring device (100) selects and connects coordinates starting from those with the greatest state similarity, but selects and connects coordinates so that the interval between coordinates is the shortest, or so that the area of ​​the shape formed when connecting the coordinates (for example, a triangle shape in the case of a two-dimensional coordinate system) is the smallest.

[0317]

[0318] The monitoring device (100) connects (N+1) coordinates across the entire coordinate system within an N-dimensional coordinate system, and performs interpolation based on the connected coordinates.

[0319] That is, taking FIG. 20 as an example, the monitoring device (100) can perform interpolation for the internal space of each triangle. At this time, a polynomial function of order 2 or higher can be utilized to perform the interpolation. For example, the contour fitting method as described above can be utilized for the interpolation, and the monitoring device (100) can generate a contour map according to the contour fitting method. However, the interpolation method performed in the embodiment of the present disclosure is not limited to the contour fitting method, and any generally known interpolation method can be used.

[0320] For example, interpolation methods such as trigonometric interpolation or cubic interpolation can also be used, and interpolation utilizing polynomial functions can be used without limitation in the interpolation method. In addition, as described above, the function on which interpolation is performed is not necessarily limited to a polynomial function of degree 2 or higher, and a zeroth or first-order function can also be used.

[0321] In other words, Fig. 20 is intended to easily show how Y coordinates are connected within a coordinate system, and the method of performing interpolation should not be interpreted as being limited to the drawing of Fig. 18.

[0322] Meanwhile, as the dimensionality of a coordinate system increases, the shapes connected within the coordinate system can also change. For example, if a three-dimensional coordinate system is formed, four coordinates can be connected. Connecting four coordinates can create multiple three-dimensional triangular pyramidal shapes across the coordinate system.

[0323]

[0324] (2) Extrapolation

[0325] The extrapolation according to the embodiment of the present disclosure may utilize at least one of the commonly known extrapolation methods. For example, the extrapolation may be performed using a polynomial function of two or more degrees. However, as described above, the function performed in extrapolation is not necessarily limited to a polynomial function of two or more degrees, and a zeroth or first-order function may also be used.

[0326] For example, Figures 19(b) and (c) show extrapolation performed using a contour fitting method. For example, when extrapolation is performed using a contour fitting method, an ellipse or circle may be used to estimate the contour.

[0327] In the case of interpolation, there is no fixed shape for the contour line, and the contour line can be formed in a shape that cannot be defined, such as an ellipse or a circle. However, in the case of extrapolation, the coordinate system of area A must be expanded to find the coordinates corresponding to the current internal state of the chamber within the expanded coordinate system, so it may be most efficient to assume a certain shape as the contour line. In addition, among the certain shapes that can be assumed as contour lines, using an ellipse or a circle may be the most effective in finding the coordinates for estimating the current internal state of the chamber. However, the use of an ellipse or a circle is not limited, and the most appropriate shape for fitting can be selected in various ways depending on the function applied to extrapolation or the results obtained through interpolation.

[0328] Fig. 21 is intended to explain a general method of performing extrapolation. Fig. 21(a) relates to a first method of performing extrapolation. In Fig. 21(a), the monitoring device (100) performs interpolation within a rectangular primary coordinate system, and the fitting result is indicated by a solid line. That is, Fig. 21(a) shows that the monitoring device (100) estimates the state similarity of the "wafer chuck height" through interpolation based on reference state data.

[0329] According to Fig. 21(a), the monitoring device (100) selects some points included in at least one region located at the outermost side from the result of fitting by interpolation in order to perform extrapolation. According to Fig. 21(a), the fitting is performed in the form of a line, and extrapolation is performed using points included in each of two regions (two elliptical dashed lines) located at both ends. That is, extrapolation can be performed using a specific function in each of the two regions.

[0330] Through this, the fitting result (solid line) derived from the existing interpolation and the fitting result (dotted line) derived from the extrapolation can be connected to derive a single fitting result, and the monitoring device (100) can estimate the coordinates at which the state similarity is maximized through this single fitting result.

[0331] Fig. 21(b) relates to a second method of performing extrapolation. In Fig. 21(b), the fitting result is indicated by a solid line by performing interpolation within a rectangular primary coordinate system, similar to Fig. 21(a). That is, Fig. 21(b) shows that the state similarity of "wafer chuck height" is estimated through interpolation based on reference state data. In Fig. 21(b), all state similarities of "wafer chuck height" indicated by solid lines are used for extrapolation fitting. The dotted line in Fig. 21(b) indicates the fitting result using extrapolation.

[0332] When extrapolation is performed as shown in Fig. 21(b), the state similarity according to the "wafer chuck height" can be newly estimated not only outside the coordinate system but also inside the coordinate system through the fitting results. That is, according to Fig. 21(b), a new state similarity can be estimated even at coordinates for which state similarity has already been estimated.

[0333] Through this, the monitoring device (100) can estimate the coordinates at which the state similarity is maximized through a fitting result such as Fig. 21(b).

[0334]

[0335] [Experimental data]

[0336] Figures 22 and 23 show experimental results to demonstrate through experiments that the estimation accuracy increases as the number of N elements selected from among M elements increases, as mentioned in [Example 4].

[0337] Specifically, FIG. 22 is intended to show the accuracy of estimating the current internal state of the chamber according to reference state data in a one-dimensional coordinate system configured by selecting only one element, and FIG. 23 is intended to show the accuracy of estimating the current internal state of the chamber according to reference state data in a two-dimensional or three-dimensional coordinate system configured by selecting two or three elements.

[0338] In the experiments of Figs. 22 and 23, multiple second state similarity data for each of the entire coordinates of the coordinate system were estimated using cubic interpolation.

[0339] Cubic interpolation uses a three-dimensional function, and uses [Mathematical Formula 4] below.

[0340]

[0341] In addition, an experiment was conducted to determine whether the internal state of the chamber could be accurately estimated according to the dimension of the coordinate system by adjusting the wafer chuck height to 0.1 mm, the wafer chuck temperature to 70 degrees, and the opening rate of the APC valve to 10%.

[0342] Figure 22 shows an experiment to determine the estimation accuracy by constructing reference state data of a one-dimensional coordinate system for “wafer chuck height.”

[0343] Referring to Fig. 22(a), the wafer chuck height was estimated to be 0 mm, which was somewhat different from the actual wafer chuck height of 0.1 mm. Fig. 22(b) is a three-dimensional graph of the results of Fig. 22(a) to more clearly visualize the experimental results when the dimension of the coordinate system is increased. Even looking at Fig. 22(b), it can be seen that there is somewhat of a difference between the actual wafer chuck height (0.1 mm) and the estimated wafer chuck height (0 mm), which is the location with the highest state similarity.

[0344] Figure 23(a) illustrates an experiment to determine the estimation accuracy by constructing reference state data in a two-dimensional coordinate system for wafer chuck height and wafer chuck temperature. That is, compared to Figure 22, an additional element called "wafer chuck temperature" was added when constructing the reference state data.

[0345] As a result of the experiment, the wafer chuck height was estimated to be 0.0999 mm, showing an estimation accuracy that was almost the same as the actual wafer chuck height of 0.1 mm. In other words, when the reference state data of the two-dimensional coordinate system by adding the wafer chuck temperature was used, the estimation accuracy of the wafer chuck height was higher than when the reference state data of the one-dimensional coordinate system for the wafer chuck height alone was used.

[0346] Figure 23(b) illustrates an experiment to determine the accuracy of estimation by constructing reference state data in a three-dimensional coordinate system for wafer chuck height, wafer chuck temperature, and APC valve opening rate. That is, compared to Figure 23(a), one more element, "APC valve opening rate," was added when constructing the reference state data.

[0347] As a result of the experiment, the wafer chuck height was estimated to be 0.1 mm, showing an estimation accuracy that perfectly matches the actual wafer chuck height of 0.1 mm. In other words, it was confirmed that the estimation accuracy for the wafer chuck height can be greatly increased by configuring the reference state data by selecting more APC valve opening rates than when using the reference state data of the one-dimensional coordinate system for only the wafer chuck height or the reference state data of the two-dimensional coordinate system for the wafer chuck height and wafer chuck temperature.

[0348] In particular, when configuring reference state data, the degree of increase in estimation accuracy due to an increase in the dimensionality of the coordinate system may vary depending on the degree of independent relationship between the selected N elements. For example, in FIGS. 22 and 23 , the independent relationship between "wafer chuck height" and "wafer chuck temperature" is relatively weak. That is, "wafer chuck height" and "wafer chuck temperature" may be dependent. At this time, the dependent relationship may be defined as when the value of any one of the selected N elements changes by a first ratio, the value of the other element changes by more than a second ratio. For example, the first ratio may be 10%, and the second ratio may be 0.1%. In other words, if the value of any one of the selected N elements increases or decreases by 10%, and the value of the other element increases or decreases by more than 0.1%, the two elements may be said to be dependent. On the other hand, if the value of one of the N selected elements increases or decreases by 10%, and the value of the other element increases or decreases by 0.1% or less, then the two elements can be said to have an independent relationship. In other words, an independent relationship can be defined as when the value of one of the N selected elements changes by a first ratio, the value of the other element changes by a second ratio or less.

[0349] In such cases, estimating the "wafer chuck height" by configuring the reference state data within a two-dimensional coordinate system for "wafer chuck height" and "wafer chuck temperature" can increase the estimation accuracy more than estimating the "wafer chuck height" by configuring the reference state data within a one-dimensional coordinate system for "wafer chuck height."

[0350] In fact, when the internal state of the chamber is estimated by configuring reference state data within a one-dimensional coordinate system for the wafer chuck height when the wafer chuck height is 0 mm and the wafer chuck temperature is 100 degrees, the estimated wafer chuck height varies depending on the wafer chuck temperature. Specifically, when estimating the internal state of the chamber when the wafer chuck height is 0 mm using the reference state data of the same wafer chuck height of 0 mm and wafer chuck temperature of 100 degrees, the wafer chuck height is estimated to be 0.03 mm when the wafer chuck temperature is 90 degrees, the wafer chuck height is estimated to be 0.06 mm when the wafer chuck height is 80 degrees, and the wafer chuck height is estimated to be 0.1 mm when the wafer chuck temperature is 70 degrees, and it can be seen that a problem similar to that described in FIG. 10 occurs.

[0351] Therefore, in such cases, it was confirmed through Figs. 20 and 21 that the estimation accuracy can be improved by configuring and measuring reference state data for a two-dimensional coordinate system of wafer chuck temperature and wafer chuck height. For example, if a two-dimensional coordinate system is formed by generating reference state data at wafer chuck temperatures of 100 degrees, 90 degrees, 80 degrees, and 70 degrees for wafer chuck heights of 0 mm, 0.03 mm, 0.06 mm, and 0.1 mm, respectively, the estimation accuracy can be further improved.

[0352] On the other hand, if the independent relationship among the selected N elements is strong, the increase in estimation accuracy may be small when the dimension of the coordinate system increases. That is, as described above, if the value of one of the N elements changes by the first ratio and the value of the other element changes by the second ratio or less, the estimation accuracy may be similar regardless of the dimension of the coordinate system. In fact, "ACP valve opening rate" and "wafer chuck height" are elements with a strong independent relationship. In this case, if the reference state data for "wafer chuck height" were configured within a one-dimensional coordinate system when the "ACP valve opening rate" was 100% and the "wafer chuck height" was 0.1 mm, even when the "ACP valve opening rate" was 80%, 60%, 40%, and 10%, the "wafer chuck height" showed the highest state similarity at 0.1 mm, which is the internal state of the actual chamber, showing that the effect of increasing the dimensionality was somewhat reduced. However, even though the "wafer chuck height" has the highest state similarity at 0.1 mm, the "ACP valve opening rate" is more distinct in the two-dimensional coordinate system than in the one-dimensional coordinate system between the state similarities at 80%, 60%, 40%, and 10%, respectively, so the current internal state of the chamber with respect to the "wafer chuck height" shows a distinct difference as the dimension of the coordinate system increases, making it easy to distinguish.

[0353]

[0354] [Example 6: Monitoring System]

[0355] A monitoring system may be provided comprising one or more of the aforementioned monitoring devices. The monitoring system may be installed in process equipment comprising one or more chambers.

[0356] Figure 24 is a block diagram of a monitoring system according to one embodiment.

[0357] Referring to FIG. 24, the monitoring system may include one or more monitoring devices (100) and management devices (200). Here, the monitoring device (100) is the monitoring device (100) described above, so a redundant description thereof will be omitted.

[0358] The monitoring system may include a management device (200). The management device (200) may manage the monitoring device (100).

[0359] The management device (200) may include a communication unit (210), a storage unit (220), and a control unit (230).

[0360] The management device (200) can communicate with the outside world through the communication unit (210). For example, the management device (200) can obtain information on the current internal state of the chamber from the monitoring device (100) through the communication unit (210). As another example, the management device (200) can transmit information on the current internal state of the chamber to an external device such as process equipment or a fab through the communication unit (210). Duplicate descriptions of similar parts to the communication unit (130) of the monitoring device (100) are omitted.

[0361] The management device (200) can store various data and programs in the storage unit (220). For example, the storage unit (220) can store information about the current internal state of the chamber. As another example, the storage unit (220) can store reference state data. In an embodiment of the present disclosure, the storage unit (220) can store Y pieces of reference state data.

[0362] Duplicate descriptions of parts similar to the storage unit (150) of the monitoring device (100) are omitted.

[0363] The control unit (230) can process and perform calculations on various types of information within the management device (200). The control unit (230) can control other components that constitute the management device (200). Duplicate descriptions of similar parts to the control unit (140) of the monitoring device (100) are omitted. For example, the control unit (230) of the management device (200), like the control unit (130) of the monitoring device (100), can generate Y pieces of reference state data and control them to be stored in the storage unit (220). In addition, the control unit (230) of the management device (200) can receive current state data from the monitoring device (100), calculate Y pieces of first state similarity, and generate Y pieces of first state similarity data. Additionally, the control unit (230) of the management device (200) can perform interpolation and / or extrapolation to determine estimated state similarity data, and can estimate the current internal state of the chamber based on the estimated state similarity data.

[0364] That is, among the operations performed by the monitoring device (100) in the above-described [Example 1] to [Example 5], all operations except for measuring frequency characteristics of a specific frequency range by transmitting and receiving radio waves can be performed or controlled to be performed by the control unit (230) of the management device (200). When the operations described in the above-described [Example 1] to [Example 5] are performed or controlled to be performed by the control unit (230) of the management device (200), the control unit (230) of the management device (200) can perform or control to perform the operations described in the above-described [Example 1] to [Example 5] for each of the plurality of monitoring devices (100).

[0365] Alternatively, when the operations described in [Example 1] to [Example 5] described above are performed or controlled to be performed by the monitoring device (100), the control unit (230) of the management device (200) can control the storage unit (220) and the communication unit (210) to transmit information on Y reference state data stored in the storage unit (220) to the monitoring device (100) according to a request of the monitoring device (100).

[0366] FIG. 25 is a schematic diagram of a monitoring system installed in process equipment according to one embodiment, in which the monitoring device is integrated. Referring to FIG. 25, each chamber (10) of the process equipment (1) may be equipped with a monitoring device (100). Even in the case of FIG. 25, each of the plurality of monitoring devices (10) may perform the operations described in [Example 1] to [Example 5]. Alternatively, the management device (200) may perform the operations described in [Example 1] to [Example 5].

[0367]

[0368] [Implementation examples of examples]

[0369] The above-described embodiments 1 to 6 are not performed independently, but can be used in combination. That is, each embodiment should not be viewed as an individual implementation example, but should be understood as a single organically connected implementation example.

[0370] For example, the execution entity that performs the operations of [Example 1] to [Example 5] may vary. If the execution entity is a monitoring device (100), the operations of [Example 1] to [Example 5] may be performed and controlled by the monitoring device (100) or the control unit (140) of the monitoring device (100). If the execution entity is a management device (200), the operations of [Example 1] to [Example 5] may be performed and controlled by the control unit (230) of the management device (200) as described in [Example 6].

[0371] In addition, for example, by performing at least some of [Example 1] to [Example 5] in combination, the current internal state of the chamber can be estimated. For example, according to the description related to [Example 1] and FIG. 5, Y reference state data are generated, and according to the description related to [Example 3] and FIG. 8, the current internal state of the chamber can be estimated. At this time, the method of performing interpolation and / or extrapolation in [Example 3] and FIG. 8 can be performed according to [Example 5]. In addition, the method of calculating state similarity in [Example 3] and FIG. 8 can be calculated according to the description related to [Mathematical Formula 1] to [Mathematical Formula 3] of [Example 2].

[0372] For another example, according to the description related to [Example 1] and FIG. 5, Y reference state data can be generated, and the current internal state of the chamber can be estimated according to [Example 4]. At this time, the method for estimating the current internal state of the chamber can be applied to at least some of the descriptions related to FIG. 8, as described in [Example 4]. At this time, the method for performing interpolation and / or extrapolation in [Example 4] can be performed according to [Example 5]. In addition, the method for calculating state similarity in [Example 4] can be calculated according to the descriptions related to [Mathematical Formula 1] to [Mathematical Formula 3] of [Example 2].

[0373]

[0374] The method according to an embodiment may be performed by processing logic including hardware, firmware, software, or a combination thereof. The method according to an embodiment may be performed by a processor executing code stored in a non-transitory computer-readable medium. Examples of the non-transitory computer-readable medium include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, and hardware devices specifically configured to store and execute program instructions such as ROMs, RAMs, and flash memories.

[0375]

[0376] Although the present disclosure has been described above based on examples, the present disclosure is not limited thereto, and it is obvious to those skilled in the art that various changes or modifications can be made within the spirit and scope of the present disclosure, and therefore, it is made clear that such changes or modifications fall within the scope of the appended patent claims.

Claims

1. In a method for estimating the state of a chamber by a chamber monitoring device, Obtain Y reference state data corresponding to Y coordinates within an N-dimensional coordinate system with each of N elements as an axis, wherein Y is a natural number greater than or equal to 2 and is a part of all coordinates that can be expressed in the N-dimensional coordinate system, and the N elements are selected from among M elements defining the state of the chamber, M is a natural number greater than or equal to 1, N is a natural number greater than or equal to 1, and M is greater than or equal to N; Transmitting radio waves of a specific frequency range into the interior of the chamber and receiving radio waves reflected from the interior of the chamber; Generate current status data indicating the status of the chamber based on the received radio waves; Determine Y first state similarities by calculating the similarity between each of the Y reference state data and the current state data; By mapping the Y first state similarities and the Y coordinates, Y first state similarity data are generated; Determining a plurality of second state similarity data for the entire coordinates by performing at least one of interpolation and extrapolation within the N-dimensional coordinate system based on the Y first state similarity data, wherein each of the plurality of second state similarity data includes a second state similarity for each of the entire coordinates; Determining the second state similarity data corresponding to the second state similarity having the maximum value among the second state similarities included in the plurality of second state similarity data as the estimated state similarity data; and Estimating the current state of each of the N elements according to the coordinates included in the estimated state similarity data; Chamber state estimation method.

2. In paragraph 1, Obtaining the Y reference state data above; Performing a first operation for each of the Y coordinates to obtain the Y reference state data; The above first operation is, Artificially adjusting the N elements to a value corresponding to one of the Y coordinates; Transmitting radio waves of the specific frequency range into the interior of the chamber and receiving radio waves reflected from the interior of the chamber; and generating reference state data indicating the state of the chamber based on the received radio waves; Chamber state estimation method.

3. In paragraph 2, Among the above M elements, the remaining elements, excluding the above N elements, are not artificially adjusted. Chamber state estimation method.

4. In paragraph 1, The above second state similarities are, The similarity between the state of the chamber and the current state data when the N elements above have a value corresponding to any one of the global coordinates is determined. Chamber state estimation method.

5. In paragraph 1, Estimating the plurality of second state similarity data; performing at least one of the interpolation and the extrapolation using a function of dimension Z or more; The above Z is a natural number greater than or equal to 0, Chamber state estimation method.

6. In paragraph 1, The above Y coordinates are selected so that the spacing between adjacent coordinates within the above N-dimensional coordinate system is constant. Chamber state estimation method.

7. In paragraph 1, The above Y coordinates are randomly selected within the above N-dimensional coordinate system. Chamber state estimation method.

8. In paragraph 1, The above Y coordinates are selected according to a preset pattern within the above N-dimensional coordinate system. Chamber state estimation method.

9. In paragraph 1, The above N is a natural number greater than or equal to 2, The above N elements are selected such that when the value of one element among the N elements changes at a first ratio, the value of at least one of the remaining elements changes by more than a second ratio. Chamber state estimation method.

10. In a chamber monitoring device that estimates the state of the chamber, An antenna that transmits radio waves of a specific frequency range into the interior of the chamber and receives radio waves reflected from the interior of the chamber; A bracket for fixing the antenna to the inside or outside of the chamber; A signal processor that applies an electric signal to the antenna and obtains an electric signal from the antenna; and A controller that controls the signal processing unit and generates status data of the chamber based on an electric signal obtained by the signal processing unit; The above controller, Obtain Y reference state data corresponding to Y coordinates in an N-dimensional coordinate system with N elements as axes, wherein Y is a natural number greater than or equal to 2 and is a part of all coordinates that can be expressed in the N-dimensional coordinate system, and the N elements are selected from M elements defining the state of the chamber, M is a natural number greater than or equal to 1, N is a natural number greater than or equal to 1, and M is greater than or equal to N; The antenna transmits radio waves of a specific frequency range into the interior of the chamber, and controls the signal processor to receive radio waves reflected from the interior of the chamber, thereby controlling the signal processor to obtain an electrical signal according to the received radio waves; Generate current status data indicating the status of the chamber based on the received radio waves; Determine Y first state similarities by calculating the similarity between each of the Y reference state data and the current state data; By mapping the Y first state similarities and the Y coordinates, Y first state similarity data are generated; Determining a plurality of second state similarity data for the entire coordinates by performing at least one of interpolation and extrapolation within the N-dimensional coordinate system based on the Y first state similarity data, wherein each of the plurality of second state similarity data includes a second state similarity for each of the entire coordinates; Determining the second state similarity data corresponding to the second state similarity having the maximum value among the second state similarities included in the plurality of second state similarity data as the estimated state similarity data; and Estimating the current state of each of the N elements according to the coordinates included in the above estimated state similarity data; Chamber monitoring device.

11. In paragraph 10, The above controller, Performing a first operation for each of the Y coordinates to obtain the Y reference state data, The above first operation is, Artificially adjusting the N elements to a value corresponding to one of the Y coordinates; The antenna transmits radio waves of the specific frequency range into the interior of the chamber, and controls the signal processor to receive radio waves reflected from the interior of the chamber, thereby controlling the signal processor to obtain an electrical signal according to the received radio waves; and generating reference state data indicating the state of the chamber based on the received radio waves; Chamber monitoring device.

12. In paragraph 11, Among the above M elements, the remaining elements, excluding the above N elements, are not artificially adjusted. Chamber monitoring device.

13. In paragraph 10, The above second state similarities are, The similarity between the state of the chamber and the current state data when the N elements above have a value corresponding to any one of the global coordinates is determined. Chamber monitoring device.

14. In paragraph 10, The above controller, Performing at least one of the interpolation and the extrapolation using a function of order Z or higher, The above Z is a natural number greater than or equal to 0, Chamber monitoring device.

15. In paragraph 10, The above Y coordinates are selected so that the spacing between adjacent coordinates within the above N-dimensional coordinate system is constant. Chamber monitoring device.

16. In paragraph 10, The above Y coordinates are randomly selected from the above Y coordinates within the above N-dimensional coordinate system. Chamber monitoring device.

17. In paragraph 10, The above Y coordinates are selected according to a preset pattern within the above N-dimensional coordinate system. Chamber monitoring device.

18. In paragraph 10, The above N is a natural number greater than or equal to 2, The above N elements are selected such that when the value of one element among the N elements changes by a first difference ratio, the value of at least one of the remaining elements changes by more than a second ratio. Chamber monitoring device.

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