Process control and monitoring methods based on plasma spectrum under dynamic plasma conditions

Abstract

Certain aspects of this disclosure provide techniques, systems, and methods for process control and monitoring under dynamic plasma boosting conditions using plasma spectra. In some cases, multiple rounds of varying plasma intensity data are collected during plasma boosting conditions in a given chamber, and statistical values ​​representing these variations in plasma intensity data are derived. Based on this data, a statistical process control (SPC) trajectory is calculated. Variations in plasma intensity data from subsequent plasma boosting conditions are acquired, and this data is compared to the SPC trajectory to determine when an anomaly (e.g., external gas, particulate matter, or other contaminants) occurs.

Description

Technical Field

[0001] Embodiments of the present invention generally relate to statistical process control (SPC) for PECVD systems and processes, and more particularly to the use of dynamic plasma intensity data for use in SPC. Background Technology

[0002] Dynamic plasma lifting, known as power lift (PL) in PECVD processes, is a process used to remove static charge from a substrate during plasma deposition. In this process, plasma is ignited, and then the gap between two electrodes (e.g., a first electrode and a bottom or chucking electrode) is moved relative to each other. At the end of the PL process, the substrate is lifted and separated from the second electrode.

[0003] When plasma intensity is measured across multiple wavelengths associated with the PL process using, for example, a spectrum analyzer, the plasma intensity typically decreases as the gap between the electrodes widens. Generally, the plasma spectrum will follow this same pattern, i.e., the spectrum will show a decrease in intensity as the electrodes separate.

[0004] However, due to the dynamic nature of the plasma spectrum during PL processes (or other processes where at least two electrodes change their relative positions to each other), there is no method to utilize the dynamic data available during this process to improve the control of the PECVD process.

[0005] Plasma intensity is typically not used to detect contaminants in a given process. If a small amount of external gas contaminates the process, the plasma intensity usually remains unchanged. Furthermore, as mentioned above, due to the dynamic nature of plasma intensity during PL processes, rapidly changing intensity data is generally considered unstable and unreliable for contamination detection.

[0006] Therefore, methods and systems are needed to utilize dynamic plasma intensity data generated when two electrodes move relative to each other, such as in PL processes, deposition processes, chamber cleaning processes, or other processes where two electrodes move relative to each other. Summary of the Invention

[0007] The embodiments disclosed in this application generally relate to a method for detecting anomalies in a PECVD process, the method comprising the steps of: changing the plasma intensity in a chamber by moving a second electrode relative to a first electrode; providing a wavelength range for measuring the changed plasma intensity; defining a function describing the changed plasma intensity within the wavelength range; and displaying an SPC reference value based on the function, the SPC reference value comprising one of the following values: the maximum, minimum, average, median, mode, and mean value of one of the function, its derivative, and its integral.

[0008] Alternative implementations generally involve a system for detecting anomalies in a PECVD process, the system including a PECVD chamber and a spectrum analyzer coupled to the PECVD chamber and configured to measure plasma intensity, the spectrum analyzer being configured to perform a method for detecting anomalies, the method including the steps of: changing the plasma intensity in the chamber by moving a second electrode relative to a first electrode; providing a first wavelength range for measuring the changed plasma intensity; defining a function describing the changed plasma intensity within the first wavelength range; and extracting at least one value from the function, the at least one value including one of the following: a maximum, minimum, mean, median, mode, and average of the function, its derivative, and its integral.

[0009] Further embodiments generally relate to a non-transient computer-readable medium containing computer-readable instructions for detecting anomalies in a PECVD process, the method comprising the steps of: changing the plasma intensity in a chamber by moving a second electrode relative to a first electrode; providing a first wavelength range for measuring the changed plasma intensity; defining a function describing the changed plasma intensity within the first wavelength range; and extracting at least one value from the function, the at least one value comprising one of the following: a maximum, minimum, mean, median, mode, and average of the function, its derivative, and its integral. Attached Figure Description

[0010] The features of this disclosure have been briefly summarized above and are described in more detail below. A more detailed understanding can be obtained by referring to embodiments of this invention, some of which are illustrated in the accompanying drawings. However, it is important to note that the drawings illustrate only exemplary embodiments and should not be considered as limiting the scope of this disclosure, which allows for other equivalent embodiments.

[0011] Figure 1 A deposition system according to the disclosed embodiments is illustrated.

[0012] Figure 2 The illustration depicts multiple plasma intensity measurements taken during the PL process according to the disclosed embodiments.

[0013] Figure 3 illustrates a line graph of a sample trace representing plasma intensity measurement and a set of line graphs of SPC data of the sample trace, according to the disclosed embodiments.

[0014] Figure 4 illustrates a line graph of multiple sample curves representing regions of varying plasma intensity according to the disclosed embodiments, and a set of line graphs representing statistical values ​​of each sample curve in the SPC graph.

[0015] Figure 5 A method for process control and monitoring under dynamic plasma conditions according to the disclosed embodiments is illustrated.

[0016] Figure 6 A computer system for process control and monitoring under dynamic plasma lifting conditions, according to the disclosed embodiments, is illustrated.

[0017] For ease of understanding, the same reference numerals are used to refer to the same elements common to all figures, where possible. It is anticipated that elements and features in one embodiment may be advantageously incorporated into other embodiments without further explanation. Detailed Implementation

[0018] In the following description, reference is made to embodiments of this disclosure. However, it should be understood that this disclosure is not limited to the specific embodiments described. Rather, any combination of the following features and elements may be contemplated to implement and practice this disclosure, whether or not they are associated with different embodiments. Furthermore, while embodiments of this disclosure may achieve advantages relative to other possible solutions and / or relative to the prior art, this does not limit the disclosure regardless of whether a particular advantage is achieved by a given embodiment. Therefore, the following aspects, features, embodiments, and advantages are merely exemplary and should not be considered elements or limitations of the appended claims unless expressly stated in the claims. Similarly, reference to “this disclosure” should not be construed as a generalization of any inventive subject matter disclosed herein and should not be considered elements or limitations of the appended claims unless expressly stated in the claims.

[0019] This disclosure generally relates to methods and systems for detecting anomalies using dynamic plasma intensity data, such as external gases, contaminants, particles, chamber anomalies, process anomalies, or other conditions in a PECVD process that may cause changes in plasma spectral intensity. This disclosure generally describes a process control and chamber monitoring method in which plasma intensity spectral data obtained during dynamic plasma conditions such as PL processes, chamber cleaning, deposition, or other processes where upper and lower electrodes move relative to each other are used to design one or more functions to fit a set of intensity values ​​across one or more wavelength ranges in one or more runs. From these functions, discrete values ​​(e.g., mean, average, median, mode, maximum, minimum, etc.) representing statistical data derived from the functions are developed for each run, wherein the statistical data is used to populate a statistical process control chart to determine a reference statistical trajectory. In subsequent runs, additional functions are designed and statistical data are derived for each run, and these data are compared to the reference trajectory. Differences observed in these subsequent runs, if any, may indicate the presence of one or more anomalies in those runs.

[0020] Figure 1 A deposition system 100 according to the disclosed embodiment is illustrated. The deposition system 100 includes a first electrode 110, a second electrode 120, a spectrum analyzer 130, and a statistical process control (SPC) computer 140. Although Figure 1The first electrode is shown as the top electrode, and the second electrode 120 is shown as the bottom electrode. However, in some embodiments, the first electrode 110 may be the bottom electrode, and the second electrode 120 may be the top electrode. In some embodiments, the SPC computer 140 and the spectrum analyzer may be part of the same physical computer system, while in other embodiments, the SPC computer may be a separate computer system. The SPC computer 140 may be a physical or virtual computer system, or a combination of physical and virtual components.

[0021] The deposition system 100 can be any type of deposition system capable of striking plasma and providing relative movement between the first electrode 110 and the second electrode 120. The first electrode 110 and the second electrode 120 can move relative to each other to generate dynamic plasma conditions, such as plasma boosting conditions (sometimes referred to as power-lift (“PL”) processes), which can be performed to eliminate static charge on the substrate during the plasma deposition process. Additional dynamic plasma conditions may include any process in which the first and second electrodes move relative to each other. During this process, plasma is ignited between these electrodes, and the gap between these electrodes gradually increases until the substrate is lifted from and separated from the second electrode 120. Other plasma deposition processes that cause the first electrode 110 and the second electrode 120 to move relative to each other may exist, such as, for example, plasma cleaning and chamber plasma seasoning processes, which may utilize the techniques disclosed herein. For simplicity, any such process will be referred to herein as a PL process. In some embodiments, only the first electrode 110 may move, or only the second electrode 120 may move, while in other embodiments, both electrodes may move.

[0022] Although spectrum analyzer 130 is specifically mentioned here, in the implementations of the techniques disclosed herein, any type of measuring device or sensor capable of measuring plasma intensity values ​​that change over time during a PL process can be used.

[0023] Figure 2 The illustration shows multiple plasma intensity measurements 200 taken during the PL process according to the disclosed embodiments.

[0024] During the PL process, as the first electrode 110 and the second electrode 120 move relative to each other, the spectrum analyzer 130 measures multiple plasma intensity trajectories over time. Within a given set of trajectories, there may be one or more regions exhibiting, in some embodiments, a local increase (or decrease) in plasma intensity, typically measured in intensity counts, as the electrodes move relative to each other. The first region 210, for example, has a first step 215, a second step 220, and a third step 225, which are measured at different time points during electrode separation, resulting in a decrease in plasma intensity in the first region 210. Simultaneously, as the first electrode 110 and the second electrode 120 move toward each other, in some embodiments, the plasma intensity in the first region 210 may increase. In this example of increase, the third step 225 may represent a measurement at a first time point, the second step 220 a measurement at a second time point, and the first step 215 a measurement taken at a third time point. Although three measurements are shown here, it should be understood that any number of measurements of plasma intensity over time in local regions of the spectrum can be made and utilized according to the embodiments described herein.

[0025] Figure 3 illustrates a set of line graphs 300 representing sample trajectories of plasma intensity measurements and SPC line graphs of the sample trajectories according to the disclosed embodiment. A first spectrogram 305, representing multiple line graphs of plasma intensity changing over time for multiple rounds in a given chamber, is a region of interest for spectral readings of a region, such as... Figure 2 The first region is 210. These line graphs are constructed using the PN function:

[0026]

[0027] RI is the relative intensity measured from a selected wavelength range. In some implementations, the relative intensity can be the plasma intensity of a single wavelength region or a combination of multiple regions using mathematical relationships (such as multiplication or division). A "power tuning" value is assigned to each exponent n coefficient parameter based on the desired function sensitivity, the gases present in the process, and potential anomalies that may exist in the process. For example, a sample PN function plot for obtaining 22 spectral measurements is sampled from 64X nm (e.g., 640 nm) to 72X nm (e.g., 720 nm), without assigning a value to the exponent n coefficient.

[0028]

[0029] From each line plot of the first spectrogram 305, there is a range of values ​​indicating the plasma intensity within the period defined by the line plot. A sample of these values ​​is shown in circle 307. Statistical values, such as, for example, the mean, median, mode, average, maximum, minimum, or other values ​​that reflect the representative values ​​of the range and / or the derivatives or integrals of these values, can be derived from the range of values ​​for each line plot.

[0030] Once the statistical values ​​for each line plot of the first spectrogram 305 are determined, the sample range of these values ​​indicated by circle 307 is represented in the first SPC line plot 310 by the first SPC reference value 312. In the representative plot shown, the first SPC mean 315 is shown; however, this can be any statistical value, such as the mean, median, mode, average, maximum, minimum, or other value that reflects the relative value of the representative value and / or the derivative or integral of these values. Furthermore, the first SPC boundary 320 can be used to show, for example, one or more standard deviations from the first SPC mean 315, selected to be suitable for the chambers and processes being evaluated, such as… Figure 1 As shown in the diagram.

[0031] Once the first SPC reference value 312 is provided as described above, this data can be used in future rounds for comparison with data derived later.

[0032] When the chamber is used for processing in a subsequent round (e.g., a PECVD process for producing semiconductor devices or displays), additional data from that subsequent round is collected in a similar manner to that described above, and this data is shown in the second spectrogram 330. New spectrogram data samples, such as those collected in sample region 331, are indicated by open circles at the measurement points. Similar to the discussion above, statistical values ​​representing these new spectrogram data samples are determined, and second SPC data 333 from sample region 331 is added to the first SPC reference value 312 in the first SPC line graph 310, resulting in the second SPC line graph 335, where open circles on the second SPC line graph 335 indicate the statistical values ​​used for the new spectrogram data. As can be seen in the second SPC line graph 335, at least one value is outside the second SPC boundary 340, which can indicate anomalies occurring under desired SPC boundary conditions. The second SPC boundary may be the same as the first SPC boundary 320, and in some embodiments, it may be a different value. By fixing the SPC boundary, future data derived from the chamber and process spectrum data can be measured relative to the first SPC reference value 312.

[0033] Figure 4 illustrates multiple sample curves of a region of altered plasma intensity, which can be combined by a specific or designed numerical function of a specific exponent (power) according to the disclosed embodiments, and a set of line graphs 400 representing the statistical values ​​of each sample curve in the SPC diagram.

[0034] This set of line graphs 400 is derived from a similar PN function as described above, where a power adjustment is applied to the exponential coefficient values. For example, the PN function describing this set of line graphs 400 has power-adjusted coefficient values:

[0035]

[0036] By modifying the power adjustment applied to the exponential coefficient values, the PN function can be made more or less sensitive to desired chamber and process conditions. For example, it is possible to... Figure 3D As can be seen, it appears that only one data point is outside the first SPC boundary 320. However, by modifying the exponential coefficient of the PN function while using the same sample data values, additional sensitivity is provided in the exemplary data, resulting in two data points exceeding the second SPC boundary 420. Selected values ​​for modifying the exponential coefficient of the PN function are chosen for specific processes, chambers, gases, and other materials present within the chamber, etc., to provide the desired level of function sensitivity, enabling the indication of the presence of anomalies.

[0037] Figure 5A method 500 for process control and monitoring under dynamic plasma conditions according to the disclosed embodiments is illustrated.

[0038] At 505, the method changes the plasma intensity in the chamber by moving the second electrode relative to the first electrode, while at 510, method 500 provides a wavelength range for measuring the changed plasma intensity.

[0039] In 515, a function describing the changed plasma intensity within the wavelength range is defined. In some embodiments, this is defined by providing a product / ration of relative intensities from the first wavelength range, the product / ration of relative intensities having a numerical component defined by the numerical value of the function at time t; and assigning a first exponential coefficient to the numerical component. In some embodiments, the exponential component may be adjusted such that a second value falls outside a single standard deviation of the SPC reference value.

[0040] At 520, the method displays an SPC reference value from the function, the SPC reference value including one of the following values: the maximum, minimum, mean, median, mode, and average of the function and / or its derivative or integral.

[0041] In several embodiments, method 500 may further include the steps of: changing a second plasma intensity in a chamber by moving a second electrode relative to a first electrode (or moving a first electrode relative to a second electrode); defining a second function describing the changed second plasma intensity within a first wavelength range; and displaying at least one second value from the second function, wherein the at least one second value of the function and / or the derivative or integral of the function includes one of the following values: the maximum, minimum, mean, median, mode, and average of the second function and / or the derivative or integral of the second function. Further embodiments include the steps of: comparing an SPC reference value with the at least one second value, wherein the difference between the SPC reference value and the at least one second value indicates the presence of an anomaly; and updating a user display to indicate the presence of an anomaly. These embodiments may include the steps of: performing the plasma intensity changing step multiple times to define a plurality of functions describing the changed plasma intensity within the first wavelength range; and extracting at least one value from each of the plurality of functions, each at least one value including one of the following values: the maximum, minimum, mean, median, mode, and average of each of the plurality of functions and / or the derivative or integral of the plurality of functions. Multiple implementations may further include the step of: plotting at least one value from each of the plurality of functions to further include the SPC reference value, wherein the second value differs from at least one standard deviation from at least one value from each of the plurality of functions.

[0042] Figure 6 A computer system 600 for process control and monitoring under dynamic plasma lifting conditions, according to the disclosed embodiments, is illustrated. These embodiments are, for example, related to... Figure 1-5 Implementation methods of the described method. In some implementations, the SPC computer 140 includes one or more components of the computer system 600.

[0043] Computer system 600 includes a central processing unit (CPU) 602 connected to a data bus 616. CPU 602 is configured to process, for example, computer-executable instructions stored in memory 608 or storage device 610, and to cause server 601 to execute, for example, instructions regarding… Figure 1-5 The methods described herein. CPU 602 is included to represent a single CPU, multiple CPUs, a single CPU with multiple processing cores, and other forms of processing architecture capable of executing computer-executable instructions.

[0044] Computer system 600 further includes input / output (I / O) devices 612 and interface 604, allowing server 601 to interface with input / output devices 612 (e.g., keyboard, display, mouse, pen input device, and other devices that allow interaction with server 601). Note that server 601 can connect to external I / O devices (e.g., external display devices) via physical and wireless connections.

[0045] The computer system 600 further includes a network interface 606, which provides the server 601 with access to an external network 614, thereby enabling access to an external computing device.

[0046] Computer system 600 further includes memory 608, which in this example includes components for performing... Figure 1-5 The operation described in the document includes a change module 618, a provision module 620, a definition module 622, a display module 624, a comparison module 626, and an update module 628.

[0047] Note that, although for the sake of simplicity, Figure 6 A single memory 608 is shown, but the various aspects stored in memory 608 can be stored in different physical memories, including memories remote from computer system 600, but all of these are accessible via CPU 602 through internal data connections (such as bus 616).

[0048] Storage device 610 further includes plasma intensity data 630, which can be displayed as follows: Figure 1-5 The plasma intensity measured is as described in the text.

[0049] Storage device 610 further includes wavelength data 632, which can be like... Figure 1-5 As described in the wavelength range.

[0050] Storage device 610 further includes function data 634, which can be like... Figure 1-5 As described in the PN function.

[0051] Storage device 610 further includes SPC reference data 636, which can be like... Figure 1-5 The SPC reference value is as described in the document.

[0052] The storage device 610 further includes abnormal data 638, which can be like those abnormalities described above.

[0053] Despite Figure 6 It is not shown in the diagram, but other aspects may be included in the storage device 610.

[0054] Similar to memory 608, for simplicity, in Figure 6 A single storage device 610 is illustrated, but the various aspects stored in storage device 610 may be stored in different physical storage devices, all of which are accessible to CPU 602 via internal data connections (such as bus 616) or external connections (such as network interface 606). Those skilled in the art will understand that one or more components of server 601 may be located remotely and are accessible via network 614.

[0055] The foregoing description is provided to enable any person skilled in the art to practice the various embodiments described herein. The examples discussed herein are not intended to limit the scope, applicability, or implementation set forth in the claims. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments. For example, the function and arrangement of the elements discussed may be changed without departing from the scope of this disclosure. Various processes or components may be appropriately omitted, substituted, or added in various examples. For example, the described methods may be performed in a different order than that described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined in some other examples. For example, an apparatus or method may be implemented using any number of aspects set forth herein. Moreover, the scope of this disclosure is intended to cover such apparatuses or methods practiced using various aspects of the disclosure set forth herein and / or other structures and functions besides those set forth herein. It should be understood that any aspect of the disclosure herein may be embodied by one or more elements of the claims.

[0056] As used herein, the phrase “at least one of a list of items” refers to any combination of these items, including a single member. For example, “at least one of a, b, or c” is intended to cover: a, b, c, ab, ac, bc, with abc, and any combination with multiple identical elements (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, with ccc, or any other order of a, b, and c).

[0057] As used herein, the term "determining" encompasses a wide variety of actions. For example, "determining" can include calculation, computation, processing, derivation, research, lookup (e.g., consulting a table, database, or other data structure), exploration, and similar actions. Furthermore, "determining" can include receiving (e.g., receiving information), accessing (or retrieving) (e.g., accessing data in memory), and similar actions. Moreover, "determining" can include parsing, selecting, choosing, establishing, and similar actions.

[0058] The methods disclosed herein include one or more steps or actions for implementing these methods. These method steps and / or actions may be interchanged with each other without departing from the scope of the claims. In other words, the order and / or use of specific steps and / or actions may be modified without departing from the scope of the claims unless a specific order of steps or actions is specified. Furthermore, various operations of the above methods can be performed by any suitable means capable of performing the corresponding functions. Such means may include various hardware and / or software components and / or modules, including but not limited to circuits, application-specific integrated circuits (ASICs), or processors. Typically, in the case of illustrated operations, those operations may have corresponding paired means-plus-function components with similar numbering.

[0059] Various illustrative logic blocks, modules, and circuits described herein can be implemented or executed using a general-purpose processor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic device, discrete hardware component, or any combination thereof designed to perform the functions described herein. The general-purpose processor may be a microprocessor, but alternatively, it may be any commercially available processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0060] A bus architecture can be used to implement the processing system. The bus can include any number of interconnect buses and bridges, depending on the specific application and overall design constraints of the processing system. The bus can link various circuits together, including processors, machine-readable media, and input / output devices. User interfaces (e.g., keyboards, displays, mice, joysticks, etc.) can also be connected to the bus. The bus can also link various other circuits, such as timing sources, peripherals, voltage regulators, power management circuits, and other circuit elements well known in the art, and therefore will not be described further. The processor can be implemented using one or more general-purpose processors and / or special-purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuits capable of executing software. Those skilled in the art will recognize how best to implement the described functionality for the processing system, depending on the specific application and the overall design constraints imposed on the system.

[0061] If implemented in software, these functions may be stored or transmitted as one or more instructions or code on a computer-readable medium. Software should be broadly interpreted to mean instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Computer-readable media includes both computer storage media and communication media, such as any medium that facilitates the transfer of a computer program from one place to another. The processor may be responsible for managing the bus and general processing, including executing software modules stored on the computer-readable storage medium. The computer-readable storage medium may be coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Alternatively, the storage medium may be integrated into the processor. For example, a computer-readable medium may include a transmission line, a carrier wave modulated by data, and / or a separate computer-readable medium with instructions stored thereon, all accessible (or accessed) by the processor via a bus interface. Alternatively or additionally, a computer-readable medium or any part thereof may be integrated into the processor; this could be in the case of a cache memory and / or a general-purpose register file. For example, examples of machine-readable storage media may include RAM (random access memory), flash memory, ROM (read-only memory), PROM (programmable read-only memory), EPROM (erasable programmable read-only memory), EEPROM (electrically erasable programmable read-only memory), registers, disks, optical disks, hard disks, or any other suitable storage media or any combination thereof. Machine-readable media may be embodied in a computer program product.

[0062] Software modules may include single or multiple instructions and may be distributed across several different code segments, within different programs, and across multiple storage media. Computer-readable media may include several software modules. These software modules include instructions that, when executed by a device (such as a processor), cause the processing system to perform various functions. Software modules may include transfer modules and receive modules. Each software module may reside in a single storage device or be distributed across multiple storage devices. For example, when a triggering event occurs, a software module may be loaded from a hard disk drive into RAM. During the execution of a software module, the processor may load some instructions into cache memory to improve access speed. One or more cache memory lines may then be loaded into a general-purpose register file for execution by the processor. When referring to the functionality of a software module, it will be understood that such functionality is implemented by the processor when instructions from that software module are executed.

[0063] The following claims are not intended to be limited to the embodiments shown herein, but should be granted the full scope consistent with the language of the claims. In a claim, unless specifically stated otherwise, reference to an element in the singular form is not intended to mean “one and only one,” but rather “one or more.” Unless specifically stated otherwise, the term “some” refers to one or more. No element of a claim should be interpreted in accordance with the provisions of Section 112(f) of the U.S. Patent Code, unless the element is expressly stated using the phrase “means for,” or, in the case of a method claim, using the phrase “for the step of.” All structural and functional equivalents of the various aspects described throughout this disclosure that are known or hereafter known to a person skilled in the art are expressly incorporated herein by reference and are intended to be covered by the claims. Furthermore, nothing disclosed herein is intended to be offered to the public, whether or not such disclosure is expressly stated in the claims.

Claims

1. A method for detecting anomalies in a PECVD process, comprising the following steps: The plasma intensity in the chamber is changed by moving the second electrode relative to the first electrode. Provides the wavelength range in which the altered plasma intensity is measured; Define a function that describes the change in plasma intensity within the wavelength range; Display SPC reference values ​​based on the function, the SPC reference values ​​comprising one of the following values: the maximum, minimum, mean, median, mode, and average of one of the function, its derivative, and its integral; and Anomalies in the PECVD process are detected by comparing the changed plasma intensity with the SPC reference value.

2. The method of claim 1, further comprising the following steps: The intensity of the second plasma in the chamber is changed by moving the second electrode relative to the first electrode. Define a second function to describe the change in the second plasma intensity within the wavelength range; Display at least one second value derived from the second function, said at least one second value comprising one of the following values: the maximum, minimum, mean, median, mode, and average of the second function, its derivative, and its integral; and Compare the SPC reference value with the at least one second value. The difference between the SPC reference value and the at least one second value indicates the presence of an anomaly; and Update the user display to indicate the presence of the anomaly.

3. The method of claim 2, wherein the step of changing the plasma intensity is performed multiple times to define a plurality of functions describing the change in plasma intensity within the wavelength range, the plurality of functions comprising one of the following functions: each of the plurality of functions, the derivative of at least one of the plurality of functions, and at least one integral of one of the plurality of functions; and Extract at least one value from each of the plurality of functions, each at least one value including one of the following: the maximum value, minimum value, mean, median, mode, and average value of each of the plurality of functions.

4. The method of claim 3, further comprising the following steps: Plot at least one value from each of the plurality of functions to further include the SPC reference value, wherein the second value differs from at least one value from each of the plurality of functions by at least one standard deviation.

5. The method of claim 1, wherein the step of defining the function comprises the following steps: From the wavelength range, a product / ratio of relative intensity is provided, the product / ratio of relative intensity having a numerical component defined by the value of the function at time t; Assign the first exponential coefficient to the numerical component; and The second exponential coefficient is assigned to the product / ratio.

6. The method of claim 2, wherein the step of defining the function comprises the following steps: From the wavelength range, a product / ratio of relative intensity is provided, the product / ratio of relative intensity having a numerical component defined by the value of the function at time t; Assign the first exponential coefficient to the numerical component; and Assign the second exponential coefficient to the product / ratio. The method further includes the following steps: adjusting one of the first exponential coefficient and the second exponential coefficient so that the second value appears abnormal relative to the SPC reference value.

7. A system for detecting anomalies in a PECVD process, comprising: PECVD chamber; and A spectrum analyzer, coupled to the PECVD chamber and configured to measure plasma intensity, is configured to perform a method for detecting anomalies, the method comprising the following steps: The plasma intensity in the chamber is changed by moving the second electrode relative to the first electrode. Provides a first wavelength range for measuring the changing plasma intensity; Define a function that describes the change in plasma intensity within the first wavelength range; Extract at least one value from the function, the at least one value comprising one of the following: the maximum, minimum, mean, median, mode, and average of the function, its derivative, and its integral; and Anomalies in the PECVD process are detected by comparing the changed plasma intensity with the SPC reference value.

8. The system of claim 7, further comprising the spectrum analyzer configured to perform the method for detecting anomalies, the method further comprising the following steps: The intensity of the second plasma in the chamber is changed by moving the second electrode relative to the first electrode. Define a second function to describe the change in the second plasma intensity within the first wavelength range; Display at least one second value derived from the second function, said at least one second value comprising one of the following: the maximum value, minimum value, mean, median, mode, and average value of the second function; and Compare the at least one value with the at least one second value. The difference between the at least one value and the at least one second value indicates the presence of an anomaly; and Update the user display to indicate the presence of the anomaly.

9. The system of claim 8, further comprising the spectrum analyzer configured to perform the method for detecting anomalies, wherein the step of changing the plasma intensity is performed multiple times to define a plurality of functions describing the change in plasma intensity within the first wavelength range, the plurality of functions comprising one of the following functions: each of the plurality of functions, the derivative of at least one of the plurality of functions, and at least one integral of one of the plurality of functions; and Extract at least one value from each of the plurality of functions, each at least one value including one of the following: the maximum value, minimum value, mean, median, mode, and average value of each of the plurality of functions.

10. The system of claim 8, further comprising the spectrum analyzer configured to perform the method for detecting anomalies, the method further comprising the following steps: Plot at least one value from each of the plurality of functions, further including the at least one value, wherein the second value differs from at least one of the at least one value from each of the plurality of functions by at least one standard deviation.

11. The system of claim 7, further comprising the spectrum analyzer configured to perform the method for detecting contamination, wherein the step of defining the function comprises the following steps: From the first wavelength range, a product / ratio of relative intensities is provided, the product / ratio of relative intensities having a numerical component defined by the value of the function at time t; Assign the first exponential coefficient to the numerical component; and The second exponential coefficient is assigned to the product / ratio.

12. The system of claim 11, further comprising the spectrum analyzer configured to perform the method for detecting anomalies, the method further comprising the following steps: Adjust one of the first and second exponential coefficients so that the second value appears abnormal relative to the SPC reference value.

13. The system of claim 11, comprising the spectrum analyzer configured to perform the method for detecting anomalies, wherein the first wavelength range comprises a plurality of wavelength ranges and at least one numerical component corresponding to each of the plurality of wavelength ranges.

14. A non-transitory computer-readable medium containing computer-readable instructions for performing a method for detecting anomalies in a PECVD process, the method comprising the steps of: The plasma intensity in the chamber is changed by moving the second electrode relative to the first electrode. Provides a first wavelength range for measuring the changing plasma intensity; Define a function that describes the change in plasma intensity within the first wavelength range; Extract at least one value from the function, the at least one value comprising one of the following: the maximum, minimum, mean, median, mode, and average of the function, its derivative, and its integral; and Anomalies in the PECVD process are detected by comparing the changed plasma intensity with the SPC reference value.

15. The non-transitory computer-readable medium of claim 14, wherein the step of defining the function comprises the following steps: From the first wavelength range, a product / ratio of relative intensities is provided, the product / ratio of relative intensities having a numerical component defined by the value of the function at time t; Assign the first exponential coefficient to the numerical component; and The second exponential coefficient is assigned to the product / ratio.

16. A method for detecting anomalies in a PECVD process, comprising the following steps: The plasma intensity in the chamber is changed by moving the second electrode relative to the first electrode. Provides the wavelength range in which the altered plasma intensity is measured; Define a function that describes the change in plasma intensity within the wavelength range; Display SPC reference values ​​based on the function, the SPC reference values ​​including one of the following values: the maximum, minimum, mean, median, mode, and average of the function, its derivative, and its integral; The intensity of the second plasma in the chamber is changed by moving the second electrode relative to the first electrode. Define a second function to describe the change in the second plasma intensity within the wavelength range; Display at least one second value derived from the second function, said at least one second value comprising one of the following values: the maximum, minimum, mean, median, mode, and average of the second function, its derivative, and its integral; and Compare the SPC reference value with the at least one second value. The difference between the SPC reference value and the at least one second value indicates the presence of an anomaly; and Update the user display to indicate the presence of the anomaly.

17. A system for detecting anomalies in a PECVD process, comprising: PECVD chamber; and A spectrum analyzer, coupled to the PECVD chamber and configured to measure plasma intensity, is configured to perform a method for detecting anomalies, the method comprising the following steps: The plasma intensity in the chamber is changed by moving the second electrode relative to the first electrode. Provides a first wavelength range for measuring the changing plasma intensity; Define a function that describes the change in plasma intensity within the first wavelength range; Extract at least one value from the function, the at least one value including one of the following: the maximum value, minimum value, mean, median, mode, and average value of the function, its derivative, and its integral; The intensity of the second plasma in the chamber is changed by moving the second electrode relative to the first electrode. Define a second function to describe the change in the second plasma intensity within the first wavelength range; Display at least one second value derived from the second function, said at least one second value comprising one of the following: the maximum value, minimum value, mean, median, mode, and average value of the second function; and Compare the at least one value with the at least one second value. The difference between the at least one value and the at least one second value indicates the presence of an anomaly; and Update the user display to indicate the presence of the anomaly.

18. A non-transitory computer-readable medium containing computer-readable instructions for performing a method for detecting anomalies in a PECVD process, the method comprising the steps of: The plasma intensity in the chamber is changed by moving the second electrode relative to the first electrode. Provides a first wavelength range for measuring the changing plasma intensity; Define a function that describes the change in plasma intensity within the first wavelength range; Extract at least one value from the function, the at least one value including one of the following: the maximum value, minimum value, mean, median, mode, and average value of the function, its derivative, and its integral; The intensity of the second plasma in the chamber is changed by moving the second electrode relative to the first electrode. Define a second function to describe the change in the second plasma intensity within the first wavelength range; Display at least one second value derived from the second function, said at least one second value comprising one of the following: the maximum value, minimum value, mean, median, mode, and average value of the second function; and Compare the at least one value with the at least one second value. The difference between the at least one value and the at least one second value indicates the presence of an anomaly; and Update the user display to indicate the presence of the anomaly.

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