Plasma processing apparatus and plasma processing method

Abstract

To improve the accuracy of detecting abnormal discharges. [Solution] The plasma processing apparatus comprises a chamber, a stage, a plasma generation unit that generates plasma in the chamber by applying high-frequency power output from a high-frequency power supply to the stage via a power supply path, a first sensor having a detection electrode that induces a potential corresponding to the potential of the plasma, a second sensor that measures the DC voltage component of the high-frequency power applied to the stage, a determination unit that performs a first determination process to determine whether or not there is an abnormality during plasma generation based on the measured value MV of the first sensor, and a second determination process to determine whether or not there is an abnormality based on the measured value of the second sensor if an abnormality is determined in the first determination process. If an abnormality is determined in the second determination process, the determination unit determines that an abnormal discharge has occurred in the chamber.

Description

Technical Field

[0001] The present disclosure relates to a plasma processing apparatus and a plasma processing method.

Background Art

[0002] Conventionally, a plasma processing apparatus for plasma-processing an object to be processed such as a substrate has been known (for example, Patent Document 1). Patent Document 1 discloses "a plasma processing apparatus including a processing chamber, an electrode unit provided in the processing chamber, and a high-frequency power supply unit that generates plasma in the processing chamber by applying high-frequency power to the electrode unit, wherein the object to be processed is placed on the electrode unit and the surface of the object to be processed is etched, and further including a discharge detection sensor that detects the state of plasma discharge in the processing chamber as a potential, and a signal analysis unit that acquires and analyzes the potential detected by the discharge detection sensor as a signal, wherein the signal analysis unit sequentially repeats steps of calculating and storing an average value of absolute values of the signal within a predetermined sampling period after the start of plasma processing, and comparing an Nth average value of the absolute values in the latest Nth (N≧2) sampling period calculated with an N-nth (1≦n<N) average value of the absolute values in the nearest N-nth sampling period before the Nth sampling period, and determining that abnormal discharge has occurred when a rate of increase or decrease of the Nth average value with respect to the N-nth average value exceeds a predetermined ratio."

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] While Patent Document 1 describes a plasma processing apparatus that can detect slight abnormal discharges without reducing productivity, further improvement in detection accuracy is desired. In this context, one of the objectives of this disclosure is to improve the detection accuracy of abnormal discharges. [Means for solving the problem]

[0005] One aspect of the present disclosure relates to a plasma processing apparatus. The plasma processing apparatus includes a chamber, a stage provided in the chamber on which a substrate is placed, a plasma generation unit having a high-frequency power supply and a power supply path, which generates plasma in the chamber by applying high-frequency power output by the high-frequency power supply to the stage via the power supply path, a first sensor positioned facing the internal space of the chamber and having a detection electrode that induces a potential corresponding to the potential of the plasma, a second sensor electrically connected to the power supply path and measuring the DC voltage component of the high-frequency power applied to the stage, and a determination unit that performs a first determination process to determine whether or not there is an abnormality during plasma generation based on the measurement value of the first sensor, and a second determination process to determine whether or not there is an abnormality based on the measurement value of the second sensor if an abnormality is determined in the first determination process, wherein the determination unit determines that an abnormal discharge has occurred in the chamber if an abnormality is determined in the second determination process.

[0006] Another aspect of the present disclosure relates to a plasma processing method. The plasma processing method is performed in a plasma processing apparatus comprising: a chamber; a stage provided in the chamber on which a substrate is placed; a plasma generation unit having a high-frequency power supply and a power supply path, which generates plasma in the chamber by applying high-frequency power output by the high-frequency power supply to the stage via the power supply path; a first sensor having a detection electrode positioned opposite the internal space of the chamber and which induces a potential corresponding to the potential of the plasma; and a second sensor electrically connected to the power supply path and measuring the DC voltage component of the high-frequency power applied to the stage. The method includes a determination step of performing a first determination process to determine whether or not there is an abnormality during plasma generation based on a measurement value from the first sensor; and, if an abnormality is determined in the first determination process, a second determination process to determine whether or not there is an abnormality based on a measurement value from the second sensor, wherein in the determination step, if an abnormality is determined in the second determination process, it is determined that an abnormal discharge has occurred in the chamber. [Effects of the Invention]

[0007] According to this disclosure, the accuracy of detecting abnormal discharges can be improved. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic cross-sectional view showing an example of a plasma processing apparatus related to this disclosure. [Figure 2] This is a schematic cross-sectional view of the first sensor. [Figure 3] This is a schematic circuit diagram showing the configuration of a matching circuit. [Figure 4] This is a flowchart of an example of the plasma processing method related to this disclosure. [Figure 5] The graphs show examples of measurement data when plasma processing is performed normally. (a) shows the relationship between the measurement value of the first sensor and the processing time, and (b) shows the relationship between the rate of change of the measurement value of the second sensor and the processing time. [Modes for carrying out the invention]

[0009] Embodiments of the plasma processing apparatus and plasma processing method relating to this disclosure will be described below with examples. However, this disclosure is not limited to the examples described below. In the following description, specific numerical values ​​and materials may be given as examples, but other numerical values ​​and materials may be applied as long as the effects of this disclosure are obtained.

[0010] (Plasma treatment device) The plasma processing apparatus according to this disclosure is an apparatus for plasma processing a substrate as a workpiece. The plasma processing apparatus may be, for example, a plasma etching apparatus, a plasma cleaning apparatus (plasma cleaner), a plasma dicer, a plasma ashing apparatus, or a plasma CVD apparatus. The plasma processing apparatus comprises a chamber, a stage, a plasma generation unit, a first sensor, a second sensor, and a determination unit.

[0011] The chamber may have a horizontal base and an openable / closable lid. The lid may be opened and closed, for example, by a vertical movement or by a rotational movement. When the lid is closed, the internal space (or processing chamber) of the chamber may be sealed between the base and the lid. The lid may function as one of the electrodes for generating plasma in the chamber. The lid may be grounded.

[0012] The stage is located inside the chamber and on which the substrate is placed. The stage may be positioned to close an opening formed in the base of the chamber. The stage may also function as the other electrode for generating plasma inside the chamber.

[0013] The plasma generation unit includes a high-frequency power supply and a power supply path. The plasma generation unit generates plasma in the chamber by applying high-frequency power output from the high-frequency power supply to the stage via the power supply path. The plasma generation unit may further include a matching circuit provided in the power supply path.

[0014] The first sensor is positioned facing the internal space of the chamber. The first sensor has a detection electrode that induces a potential corresponding to the plasma potential. The first sensor may be provided to cover an opening formed in the lid of the chamber. The first sensor may be, for example, a window-type probe fixed to the lid or side wall of the chamber. There may be only one first sensor or multiple sensors. Information regarding the potential induced in the detection electrode may be sent to the determination unit via a wired or wireless connection.

[0015] The second sensor is electrically connected to the power supply path of the plasma generation unit. The second sensor measures the DC voltage component of the high-frequency power applied to the stage. This DC voltage component has a correlation with the plasma potential. The second sensor may consist of a voltmeter connected to the power supply path. The second sensor may be electrically connected to the power supply path via a low-pass filter. The sampling period of the second sensor may be longer than that of the first sensor. Information regarding the DC voltage component measured by the second sensor may be sent to the determination unit via a wired or wireless connection.

[0016] The determination unit performs a first determination process and a second determination process. The first determination process is a process that determines whether or not there is an abnormality during plasma generation based on the measurement value of the first sensor (i.e., information on the potential induced at the detection electrode). In the first determination process, for example, an abnormality may be determined if the measurement value of the first sensor exceeds a first threshold more than a specified number of times. The second determination process is a process that determines whether or not there is an abnormality based on the measurement value of the second sensor (i.e., information on the DC voltage component of the high-frequency power) if an abnormality is determined in the first determination process. In the second determination process, for example, an abnormality may be determined if the time rate of change of the measurement value of the second sensor exceeds a second threshold. Then, if an abnormality is determined in the second determination process, the determination unit determines that an abnormal discharge has occurred in the chamber.

[0017] Thus, by using the measurement values of each of the first sensor and the second sensor for abnormality determination, the detection accuracy of abnormal discharge can be improved. That is, when performing abnormality determination using only the measurement value of the first sensor (or when performing only the first determination process), even if it is determined that there is an abnormality, it is difficult to immediately determine whether this is a result of the occurrence of an actual abnormal discharge or a result of an abnormality occurring in the first sensor. In contrast, in the present disclosure, when it is determined that there is an abnormality in the first determination process, a second determination process using the measurement value of the second sensor is further performed. When it is also determined that there is an abnormality in this second determination process, it is determined again that an abnormal discharge has occurred in the chamber. Thereby, false detection of abnormal discharge can be suppressed and the detection accuracy of abnormal discharge can be improved.

[0018] When the determination unit does not determine that there is an abnormality in the second determination process, it may determine that there is an abnormality in the first sensor. According to this configuration, when it is determined that there is an abnormality in the first determination process, it is possible to determine whether this is a result of an abnormality in the first sensor or a result of the occurrence of an abnormal discharge, and conclude that it is the former. Then, if necessary, maintenance of the first sensor (for example, replacing it with a new first sensor, etc.) may be performed.

[0019] When the determination unit does not determine that there is an abnormality in the first determination process, it may perform a third determination process based on the measurement value of the second sensor. When it is determined that there is an abnormality in the third determination process, it may be determined that an abnormal discharge has occurred in the chamber. This configuration is particularly effective when the sensitivity of the second sensor is lower than the sensitivity of the first sensor (or when the sampling period of the second sensor is longer than the sampling period of the first sensor). In such a case, even if it is determined that there is an abnormality only by the first determination process using the relatively high-sensitivity first sensor, as described above, it is difficult to identify the cause. However, if it is determined that there is an abnormality only by the second determination process using the relatively low-sensitivity second sensor, it can be determined that an abnormal discharge has occurred in the chamber.

[0020] When the determination unit does not determine that there is an abnormality in the first determination process, it may perform a third determination process based on the measurement value of the second sensor. When it is not determined that there is an abnormality in the third determination process, it may be determined that abnormal discharge does not occur in the chamber. In this configuration, it is determined that abnormal discharge does not occur only when it is determined that there is no abnormality in both the first determination process and the second determination process. Therefore, compared with the case where abnormal determination is made by only one of the first determination process or the second determination process, the reliability of the determination result that abnormal discharge does not occur is improved.

[0021] (Plasma processing method) The plasma processing method according to the present disclosure may be executed in the above-described plasma processing apparatus, but can also be executed in a plasma processing apparatus not provided with a determination unit. The plasma processing method is a method executed in a plasma processing apparatus including the above-described chamber, the above-described stage, the above-described plasma generation unit, the above-described first sensor, and the above-described second sensor, and includes a determination step.

[0022] In the determination step, based on the measurement value of the first sensor, a first determination process for determining the presence or absence of an abnormality during plasma generation is performed, and when it is determined that there is an abnormality in the first determination process, based on the measurement value of the second sensor, a second determination process for determining the presence or absence of an abnormality is performed. Then, in the determination step, when it is determined that there is an abnormality in the second determination process, it is determined that abnormal discharge has occurred in the chamber. Thereby, the detection accuracy of abnormal discharge can be improved.

[0023] In the determination step, when it is not determined that there is an abnormality in the second determination process, it may be determined that there is an abnormality in the first sensor. In this case, when it is determined that there is an abnormality in the first determination process, it can be determined whether this is the result of an abnormality in the first sensor or the result of the occurrence of abnormal discharge, and it can be concluded that it is the former.

[0024] In the determination process, if no abnormality is detected in the first determination process, a third determination process based on the measurement value of the second sensor may be performed, and if an abnormality is detected in the third determination process, it may be determined that an abnormal discharge has occurred in the chamber. This configuration is particularly effective when the sensitivity of the second sensor is lower than that of the first sensor. In such cases, even if an abnormality is detected only by the first determination process using the first sensor with relatively high sensitivity, it is difficult to identify the cause. However, if an abnormality is detected only by the second determination process using the second sensor with relatively low sensitivity, it can be determined that an abnormal discharge has occurred in the chamber.

[0025] In the determination process, if no abnormality is detected in the first determination process, a third determination process based on the measurement value of the second sensor may be performed, and if no abnormality is detected in the third determination process, it may be determined that no abnormal discharge has occurred in the chamber. In this case, the reliability of the determination result that no abnormal discharge has occurred can be improved compared to when abnormality detection is performed using only one of the first or second determination processes.

[0026] As described above, according to this disclosure, by performing abnormality detection using both the first and second sensors, the accuracy of detecting abnormal discharges within the chamber can be improved. Furthermore, according to this disclosure, the reliability of the determination that no abnormal discharge has occurred within the chamber can be improved.

[0027] Hereinafter, an example of a plasma processing apparatus and plasma processing method according to this disclosure will be specifically described with reference to the drawings. The components and processes described above can be applied to the components and processes of the example plasma processing apparatus and plasma processing method described below. The components and processes of the example plasma processing apparatus and plasma processing method described below can be modified based on the above description. Furthermore, the matters described below may be applied to the above embodiments. Among the components and processes of the example plasma processing apparatus and plasma processing method described below, components and processes that are not essential to the plasma processing apparatus and plasma processing method according to this disclosure may be omitted. Note that the figures shown below are schematic and do not accurately reflect the actual shape and number of components.

[0028] (Plasma treatment device) The plasma processing apparatus 100 in this embodiment is a plasma cleaning apparatus, but is not limited to this. As shown in Figures 1 to 3, the plasma processing apparatus 100 comprises a chamber 101, an electrode section 105, a plasma generation section 120, a first sensor 160, a second sensor 180, and a control section 122.

[0029] The chamber 101 comprises a horizontal base portion 102 and an openable / closable lid portion 103. The lid portion 103 is provided to be able to move up and down by a lifting mechanism (not shown). When the lid portion 103 descends and abuts against the upper surface of the base portion 102, the chamber 101 becomes sealed and a processing chamber 101a is formed. At this time, a sealing member 104 is interposed between the lid portion 103 and the base portion 102, thereby ensuring that the processing chamber 101a is sealed. Plasma processing of the substrate 109, which is the object to be processed, is performed in the processing chamber 101a. The base portion 102 has an opening 102a formed in its central region and through holes 102b formed around the opening 102a. The processing chamber 101a is an example of the internal space of the chamber.

[0030] The electrode portion 105 is fitted into the opening 102a of the base portion 102 via an insulating member 106 so as to close it. The upper surface of the electrode portion 105 is covered with an insulating layer 107. A guide member 108 for positioning the substrate 109 is positioned on the upper surface of the insulating layer 107. A part of the electrode portion 105 (specifically the lower part) is exposed outside the chamber 101, but the portion of the electrode portion 105 on which the substrate 109 is placed is located inside the chamber 101, and this arrangement is also considered to be "the electrode portion 105 is provided inside the chamber 101". The electrode portion 105 is an example of a stage.

[0031] A conduit 111 is inserted into the through-hole 102b of the base section 102. A vent valve 112, a gas supply valve 113, a vacuum valve 114, and a vacuum gauge 115 are connected to the conduit 111. A gas supply unit 116 and a vacuum pump 117 are further connected to the gas supply valve 113 and the vacuum valve 114, respectively. By opening the vacuum valve 114 and operating the vacuum pump 117, the gas in the processing chamber 101a is discharged, and the processing chamber 101a becomes depressurized. The vacuum level in the processing chamber 101a is measured by the vacuum gauge 115. On the other hand, when the gas supply valve 113 is opened, process gas (plasma generation gas) is supplied to the processing chamber 101a from the gas supply unit 116. The gas supply unit 116 has a built-in flow rate adjustment mechanism, which adjusts the flow rate of the process gas supplied to the processing chamber 101a. When the vent valve 112 is opened, air is supplied into the processing chamber 101a.

[0032] The plasma generation unit 120 has a high-frequency power supply 119 and a power supply path equipped with a matching unit 118. The high-frequency power supply 119 is electrically connected to the electrode unit 105 via the power supply path. On the other hand, the lid unit 103 is grounded to the grounding unit 110. When process gas is supplied into the processing chamber 101a and the high-frequency power supply 119 is operated, a high-frequency voltage is applied between the electrode unit 105 and the lid unit 103. This generates plasma in the processing chamber 101a. The matching unit 118 has two variable capacitors VC1, VC2 and one fixed capacitor FC (see Figure 3) and matches the impedance between the plasma discharge circuit (not shown) that generates the plasma and the high-frequency power supply 119. The vent valve 112, gas supply valve 113, vacuum valve 114, vacuum gauge 115, gas supply unit 116, vacuum pump 117, and high-frequency power supply 119 are controlled by the control unit 122. In other words, the control unit 122 has a normal operation control function for executing plasma processing operations.

[0033] The first sensor 160 is positioned opposite the processing chamber 101a and outputs a measured value MV corresponding to the potential of the plasma generated in the processing chamber 101a. The first sensor 160 is fixed so as to cover the opening 103a provided in the lid 103.

[0034] As shown in Figure 2, the first sensor 160 comprises a dielectric member 161 and a probe electrode unit 162. The first sensor 160 is fixed to the outside of the lid 103 (opposite side from the processing chamber 101a) by a support member 170. The dielectric member 161 is flat, with one surface facing the processing chamber 101a and the other surface facing the probe electrode 162b of the probe electrode unit 162. The material of the dielectric member 161 is, for example, optically transparent glass. The material of the support member 170 is not particularly limited as long as it is conductive, for example, metal.

[0035] The probe electrode unit 162 consists of a probe electrode 162b positioned on the dielectric member 161 side, a shield electrode 162c positioned opposite it, and a glass plate 162a interposed between them. The probe electrode 162b and the dielectric member 161 are fixed together by a support member 170 so as to be in close contact. The probe electrode 162b is connected to the signal recording unit 150 via a detection wire 162d. The shield electrode 162c electrically shields the probe electrode unit 162 from the outside. The probe electrode 162b and the shield electrode 162c are formed, for example, by coating the surface of the glass plate 162a with a transparent conductive material such as ITO (indium tin oxide). Therefore, the inside of the processing chamber 101a can be viewed from the outside via the first sensor 160. The probe electrode 162b is an example of a detection electrode.

[0036] When a plasma discharge occurs inside the processing chamber 101a, the probe electrode 162b is electrically connected to the plasma P via the dielectric member 161 and the sheath (space charge layer) S formed at the interface between the generated plasma P and the dielectric member 161. That is, an electrical circuit is formed in series, consisting of a capacitor C1 formed by the dielectric member 161, a capacitor C2 having capacitance equivalent to the sheath S, and the resistance due to the plasma P, and a potential corresponding to the state of the plasma P is induced in the probe electrode 162b. In other words, a change in the potential of the probe electrode 162b represents a change in the state of the plasma P. The signal recording unit 150 receives the change in the potential of the probe electrode 162b via the detection wire 162d and temporarily records it as a digital signal. On the other hand, the charge generated on the shield electrode 162c is dissipated to the grounded cover 103 via the support member 170, thus reducing noise.

[0037] Although not shown in the diagram, the signal recording unit 150 includes an amplifier, an A / D converter, and a memory. The amplifier amplifies the potential change (change in measured value MV) of the probe electrode 162b transmitted via the detection wire 162d. The A / D converter performs A / D conversion of the potential change signal amplified by the amplifier. The A / D converted digital signal indicating the potential change is temporarily recorded in the memory according to the write control of the control unit 122. The digital signal temporarily recorded in the memory is erased according to a clear command from the control unit 122.

[0038] As shown in Figure 3, the second sensor 180 is electrically connected to the power supply path of the plasma generation unit 120 and measures the DC voltage component of the high-frequency power applied to the electrode unit 105. The second sensor 180 is electrically connected to the power supply path via a low-pass filter 181. In this embodiment, the second sensor 180 is built into the matching unit 118 and connected to the stage after the fixed capacitor FC in the power supply path, but it is not limited to this.

[0039] The control unit 122 performs a first determination process and a second determination process in addition to the normal operation control process that executes the plasma processing operation. The first determination process is a process that determines whether or not there is an abnormality during plasma generation based on the measured value MV of the first sensor 160. In the first determination process of this embodiment, an abnormality is determined if the absolute value of the measured value MV of the first sensor 160 exceeds a predetermined number of times and surpasses the first threshold TH1, but it is not limited to this. The second determination process is a process that determines whether or not there is an abnormality based on the measured value of the second sensor 180 when an abnormality is determined in the first determination process. In the second determination process of this embodiment, an abnormality is determined if the absolute value of the time change rate ΔVdc of the measured value of the second sensor 180 exceeds the second threshold TH2, but it is not limited to this. Then, if an abnormality is determined in the second determination process, the control unit 122 determines that an abnormal discharge has occurred in the chamber 101, while if an abnormality is not determined in the second determination process, it determines that there is an abnormality in the first sensor 160. The control unit 122 is an example of a determination unit.

[0040] If the control unit 122 does not determine that there is an abnormality in the first determination process, it performs a third determination process based on the measurement value of the second sensor 180. Then, if the control unit 122 determines that there is an abnormality in the third determination process, it determines that an abnormal discharge has occurred in the chamber 101, while if the control unit 122 does not determine that there is an abnormality in the third determination process, it determines that no abnormal discharge has occurred in the chamber 101.

[0041] The control unit 122 is connected to a display unit 130, an input unit 140, and a signal recording unit 150. The display unit 130 shows the results of the control unit 122's determination regarding the presence or absence of abnormal discharge. The input unit 140 receives information such as a process recipe including plasma processing conditions. The signal recording unit 150 records the change in potential (change in measured value MV) measured by the first sensor 160 as a digital signal.

[0042] (Plasma treatment method) The plasma treatment method of this embodiment can be performed in the plasma treatment apparatus 100 described above, but may also be performed in other types of plasma treatment apparatuses or plasma treatment systems. The plasma treatment method includes a determination step.

[0043] Figure 4 is a flowchart of the determination process in this embodiment. As shown in the figure, in the determination process, the first determination process ST1 is executed first, and then, if necessary, the second determination process ST2 or the third determination process ST3 is executed. The first to third determination processes ST1 to ST3 are executed while plasma processing is being performed in the chamber 101.

[0044] In the first determination process ST1, the control unit 122 determines whether or not there is an abnormality during plasma generation based on the measured value MV from the first sensor 160. Specifically, in the first determination process ST1, the control unit 122 determines that there is an abnormality if the absolute value of the measured value MV from the first sensor 160 exceeds the first threshold TH1 by a specified number of times, and determines that there is no abnormality otherwise. If an abnormality is determined in the first determination process ST1 ("Yes"), the process proceeds to the second determination process ST2. On the other hand, if an abnormality is not determined in the first determination process ST1 ("No"), the process proceeds to the third determination process ST3.

[0045] In the second determination process ST2, the control unit 122 determines whether or not there is an abnormality based on the measurement value of the second sensor 180. Specifically, in the second determination process ST2, the control unit 122 determines that there is an abnormality if the absolute value of the time rate of change ΔVdc of the measurement value of the second sensor 180 exceeds the second threshold TH2, and determines that there is no abnormality otherwise. If the second determination process ST2 determines that there is an abnormality ("Yes"), it is determined that an abnormal discharge has occurred in the chamber 101. On the other hand, if the second determination process ST2 does not determine that there is an abnormality ("No"), it is determined that there is an abnormality in the first sensor 160.

[0046] In the third determination process ST3, the control unit 122 determines whether or not there is an abnormality based on the measurement value of the second sensor 180. Specifically, in the third determination process ST3, the control unit 122 determines that there is an abnormality if the absolute value of the time rate of change ΔVdc of the measurement value of the second sensor 180 exceeds the second threshold TH2, and determines that there is no abnormality otherwise. If the third determination process ST3 determines that there is an abnormality ("Yes"), it is determined that an abnormal discharge has occurred in the chamber 101. On the other hand, if the third determination process ST3 does not determine that there is an abnormality ("No"), it is determined that no abnormal discharge has occurred in the chamber 101.

[0047] Figure 5 is a graph showing an example of measurement data when plasma processing is performed normally. In this case, as shown in Figure 5(a), the absolute value of the measured value MV from the first sensor 160 is below the first threshold TH1. Also, as shown in Figure 5(b), the absolute value of the time rate of change ΔVdc measured from the second sensor 180 is below the second threshold TH2. Applying these to the flowchart described above, the first judgment process ST1 determines that there is no abnormality, and the subsequent third judgment process ST3 also determines that there is no abnormality. On the other hand, although not shown in the diagram, for example, if the time rate of change ΔVdc measured from the second sensor 180 rises above the second threshold TH2, the second judgment process ST2 or the third judgment process ST3 will determine that there is an abnormality, and the occurrence of abnormal discharge in the chamber 101 will be detected.

[0048] [Note] The above description of embodiments discloses the following technologies. (Technology 1) Chamber and, A stage is provided within the chamber on which the substrate is placed, A plasma generation unit having a high-frequency power supply and a power supply path, which generates plasma in the chamber by applying high-frequency power output by the high-frequency power supply to the stage via the power supply path, A first sensor having a detection electrode positioned opposite the internal space of the chamber, which induces a potential corresponding to the potential of the plasma, A second sensor electrically connected to the power supply path measures the DC voltage component of the high-frequency power applied to the stage, A determination unit that performs a first determination process to determine whether or not there is an abnormality during plasma generation based on the measurement value of the first sensor, and a second determination process to determine whether or not there is an abnormality based on the measurement value of the second sensor if an abnormality is determined in the first determination process, Equipped with, The determination unit determines that an abnormal discharge has occurred in the chamber when an abnormality is determined in the second determination process, and is a plasma processing apparatus. (Technology 2) The plasma processing apparatus according to Technology 1, wherein the determination unit determines that there is an abnormality in the first sensor if no abnormality is determined in the second determination process. (Technology 3) The plasma processing apparatus according to Technology 1 or 2, wherein the determination unit performs a third determination process based on the measurement value of the second sensor if it is not determined that there is an abnormality in the first determination process, and determines that an abnormal discharge has occurred in the chamber when it is determined that there is an abnormality in the third determination process. (Technology 4) The plasma processing apparatus according to any one of the technologies 1 to 3, wherein the determination unit performs a third determination process based on the measurement value of the second sensor if it is not determined that there is an abnormality in the first determination process, and determines that no abnormal discharge has occurred in the chamber if it is not determined that there is an abnormality in the third determination process. (Technology 5) Chamber and, A stage is provided within the chamber on which the substrate is placed, A plasma generation unit having a high-frequency power supply and a power supply path, which generates plasma in the chamber by applying high-frequency power output by the high-frequency power supply to the stage via the power supply path, A first sensor having a detection electrode positioned opposite the internal space of the chamber, which induces a potential corresponding to the potential of the plasma, A second sensor electrically connected to the power supply path measures the DC voltage component of the high-frequency power applied to the stage, A plasma processing method performed in a plasma processing apparatus comprising: The system includes a determination step of performing a first determination process to determine whether or not there is an abnormality during plasma generation based on the measurement value of the first sensor, and a second determination process to determine whether or not there is an abnormality based on the measurement value of the second sensor if an abnormality is determined in the first determination process. A plasma processing method in which, in the determination step, if an abnormality is determined in the second determination process, it is determined that an abnormal discharge has occurred in the chamber. (Technology 6) The plasma processing method according to Technology 5, wherein in the determination step, if no abnormality is determined in the second determination process, it is determined that there is an abnormality in the first sensor. (Technology 7) The plasma processing method according to Technology 5 or 6, wherein, in the determination step, if no abnormality is determined in the first determination process, a third determination process is performed based on the measurement value of the second sensor, and if an abnormality is determined in the third determination process, it is determined that an abnormal discharge has occurred in the chamber. (Technology 8) The plasma processing method according to any one of technologies 5 to 7, wherein in the determination step, if no abnormality is determined in the first determination process, a third determination process is performed based on the measurement value of the second sensor, and if no abnormality is determined in the third determination process, it is determined that no abnormal discharge has occurred in the chamber. [Industrial applicability]

[0049] This disclosure can be used in plasma processing apparatus and plasma processing methods. [Explanation of symbols]

[0050] 100: Plasma processing equipment 101: Chamber 101a: Processing room (internal space) 102: Base section 102a: Opening 102b: Through hole 103: Lid 103a: Opening 104: Sealing material 105: Electrode section (stage) 106: Insulating material 107: Insulating layer 108: Guide member 109: Circuit board 110: Grounding part 111: Pipeline 112: Vent valve 113: Gas supply valve 114: Vacuum valve 115: Vacuum gauge 116: Gas Supply Department 117: Vacuum pump 118: Matching box 119: High frequency power supply 120: Plasma generation unit 121: Power supply route 122: Control Unit (Determination Unit) 130: Display section 140: Input section 150: Signal recording unit 160: First sensor 161: Dielectric material 162: Probe electrode unit 162a: Glass plate 162b: Probe electrode (detection electrode) 162c: Shielding electrode 162d: Detection wire 170: Support member 180: Second sensor 181: Low-pass filter C1, C2: Capacitors FC: Fixed Capacitor MV: Measurement value P: Plasma R: Power supply path S: Sheath TH1: First threshold TH2: Second threshold VC1, VC2: Variable capacitors ΔVdc

Claims

1. Chamber and, A stage is provided within the chamber on which the substrate is placed, A plasma generation unit having a high-frequency power supply and a power supply path, which generates plasma in the chamber by applying high-frequency power output by the high-frequency power supply to the stage via the power supply path, A first sensor having a detection electrode positioned opposite the internal space of the chamber, which induces a potential corresponding to the potential of the plasma, A second sensor electrically connected to the power supply path measures the DC voltage component of the high-frequency power applied to the stage, A determination unit that performs a first determination process to determine whether or not there is an abnormality during plasma generation based on the measurement value of the first sensor, and a second determination process to determine whether or not there is an abnormality based on the measurement value of the second sensor if an abnormality is determined in the first determination process, Equipped with, The determination unit determines that an abnormal discharge has occurred in the chamber when an abnormality is determined in the second determination process, and is a plasma processing apparatus.

2. The plasma processing apparatus according to claim 1, wherein the determination unit determines that there is an abnormality in the first sensor if no abnormality is determined in the second determination process.

3. The plasma processing apparatus according to claim 1, wherein the determination unit performs a third determination process based on the measurement value of the second sensor if it is not determined that there is an abnormality in the first determination process, and determines that an abnormal discharge has occurred in the chamber if it is determined that there is an abnormality in the third determination process.

4. The plasma processing apparatus according to any one of claims 1 to 3, wherein the determination unit performs a third determination process based on the measurement value of the second sensor if it is not determined that there is an abnormality in the first determination process, and determines that no abnormal discharge has occurred in the chamber if it is not determined that there is an abnormality in the third determination process.

5. Chamber and, A stage is provided within the chamber on which the substrate is placed, A plasma generation unit having a high-frequency power supply and a power supply path, which generates plasma in the chamber by applying high-frequency power output by the high-frequency power supply to the stage via the power supply path, A first sensor having a detection electrode positioned opposite the internal space of the chamber, which induces a potential corresponding to the potential of the plasma, A second sensor electrically connected to the power supply path measures the DC voltage component of the high-frequency power applied to the stage, A plasma processing method performed in a plasma processing apparatus comprising: The system includes a determination step of performing a first determination process to determine whether or not there is an abnormality during plasma generation based on the measurement value of the first sensor, and a second determination process to determine whether or not there is an abnormality based on the measurement value of the second sensor if an abnormality is determined in the first determination process. A plasma processing method in which, in the determination step, if an abnormality is determined in the second determination process, it is determined that an abnormal discharge has occurred in the chamber.

6. The plasma processing method according to claim 5, wherein in the determination step, if no abnormality is determined in the second determination process, it is determined that there is an abnormality in the first sensor.

7. The plasma processing method according to claim 5, wherein in the determination step, if no abnormality is determined in the first determination process, a third determination process is performed based on the measurement value of the second sensor, and if an abnormality is determined in the third determination process, it is determined that an abnormal discharge has occurred in the chamber.

8. The plasma processing method according to any one of claims 5 to 7, wherein in the determination step, if no abnormality is determined in the first determination process, a third determination process is performed based on the measurement value of the second sensor, and if no abnormality is determined in the third determination process, it is determined that no abnormal discharge has occurred in the chamber.

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