Plasma processing apparatus and plasma processing method

Abstract

To detect temperature abnormality of a substrate with high accuracy.SOLUTION: A plasma processing apparatus includes a chamber, a stage that is provided in the chamber and on which a substrate is placed, a sensor that receives infrared rays emitted from the substrate placed on the stage and outputs a measurement value T corresponding to an intensity of the received infrared rays, and a determination unit that determines whether there is a temperature abnormality of the substrate based on the measurement value T. The determination unit performs a first determination process of determining that a temperature abnormality of the substrate has occurred when a state in which a time change rate Δ T of the measurement value T exceeds a first threshold Δ T _ th continues for more than a threshold time t _ th.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Conventionally, plasma processing apparatuses that perform plasma processing on a workpiece such as a substrate are known (for example, Patent Document 1). Patent Document 1 discloses "a plasma dicing apparatus comprising: a chamber; a substrate support for supporting a non-metallic substrate of a type having a dicing lane; a plasma generator for generating plasma in the chamber suitable for plasma etching the substrate along the dicing lane; an infrared detector for monitoring infrared radiation emitted from at least a portion of the dicing lane; and a condition detector configured to detect a condition related to a final stage of a plasma dicing process from the monitored infrared radiation." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-006758 Summary of the Invention [Problem to be solved by the invention]

[0004] If a temperature abnormality (e.g., an abnormal temperature rise) occurs in a substrate during plasma processing, damage to the substrate can be minimized by quickly interrupting the plasma processing. Therefore, there is a need for a technology that can detect a temperature abnormality in a substrate with high accuracy. In this situation, one of the objects of the present disclosure is to detect a temperature abnormality in a substrate with high accuracy. [Means for solving the problem]

[0005] One aspect of the present disclosure relates to a plasma processing apparatus including a chamber, a stage provided in the chamber and on which a substrate is placed, a sensor that receives infrared rays emitted from the substrate placed on the stage and outputs a measurement value corresponding to the intensity of the received infrared rays, and a determination unit that determines whether or not a temperature abnormality has occurred in the substrate based on the measurement value, wherein the determination unit performs a first determination process to determine that a temperature abnormality has occurred in the substrate when a state in which a time rate of change of the measurement value exceeds a first threshold continues for more than a threshold time.

[0006] Another aspect of the present disclosure relates to a plasma processing method, the plasma processing method being performed in a plasma processing apparatus including a chamber, a stage provided in the chamber and on which a substrate is placed, and a sensor that receives infrared rays emitted from the substrate placed on the stage and outputs a measurement value corresponding to the intensity of the received infrared rays, the plasma processing method including a first determination step of determining that an abnormal temperature has occurred in the substrate when a state in which a time rate of change of the measurement value exceeds a first threshold continues beyond a threshold time. [Effects of the Invention]

[0007] According to the present disclosure, temperature abnormalities in a substrate can be detected with high accuracy. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view schematically illustrating an example of a plasma processing apparatus according to the present disclosure. [Figure 2] 10 is an example of a graph showing the relationship between sensor measurement values ​​and processing time during plasma processing, corresponding to the case where unit processing is normally repeated. [Figure 3] 10 is an example of a graph showing the relationship between sensor measurement values ​​and processing time during plasma processing, which corresponds to a case where an abnormality in the temperature of the substrate occurs. [Figure 4] 4 is an example of a graph showing the relationship between sensor measurement values ​​during plasma processing and processing time, and corresponds to a case where a substrate temperature abnormality occurs in a manner different from that of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Embodiments of a plasma processing apparatus and a plasma processing method according to the present disclosure will be described below using examples. However, the present disclosure is not limited to the examples described below. While specific numerical values ​​and materials may be used in the following description, other numerical values ​​and materials may be used as long as the effects of the present disclosure are obtained.

[0010] (Plasma processing equipment) The plasma processing apparatus according to the present disclosure is an apparatus for plasma processing a substrate as a processing object. The plasma processing apparatus may be, for example, a plasma etching apparatus, a plasma dicer, a plasma ashing apparatus, or a plasma CVD apparatus. The plasma processing apparatus includes a chamber, a stage, a sensor, and a determination unit.

[0011] The chamber may have an opening at the top. The opening may be open upward. The chamber may be formed in a hollow cylindrical shape. The chamber may be made of metal and may be grounded.

[0012] The stage is provided in the chamber, and a substrate is placed on it. The stage may have a horizontal mounting surface on which the substrate is placed. The stage may have a flow path through which a coolant flows to cool the substrate during plasma processing. The stage may have an electrostatic chucking mechanism for attracting the substrate. The stage may have a lower electrode to which high-frequency power is applied. The substrate may be, for example, a semiconductor substrate to be singulated by plasma etching. The semiconductor substrate has a plurality of element regions and division regions that define the element regions. The element regions include, for example, a semiconductor layer and a wiring layer. Element chips having the semiconductor layer and the wiring layer are obtained by etching the division regions. The substrate may be placed on the stage while supported by a carrier. The carrier may be, for example, a resin sheet held at its outer periphery by a frame.

[0013] The sensor receives infrared rays emitted from the substrate placed on the stage. The sensor outputs a measurement value corresponding to the intensity of the received infrared rays. The manner in which the measurement value is output is not particularly limited, and for example, a voltage having a magnitude corresponding to the intensity of the received infrared rays may be output. The intensity of the infrared rays emitted from the substrate may increase as the temperature of the substrate increases.

[0014] The determination unit determines whether or not there is a temperature abnormality in the substrate based on the measurement value output by the sensor. Specifically, the determination unit determines that a temperature abnormality in the substrate has occurred when the time rate of change of the measurement value (i.e., the amount of change in the measurement value per unit time) exceeds a first threshold value and continues to do so for more than the threshold time. The determination unit may be included in a control device provided in the plasma processing apparatus, or may be included in a device separate from the plasma processing apparatus (e.g., an information processing apparatus). The first threshold value may be, for example, 2°C / second or more when the measurement value is converted into the temperature of the substrate. The threshold time may be, for example, 2 seconds or more and 5 seconds or less.

[0015] As a result of extensive research, it was found that this determination method enables highly accurate detection of substrate temperature abnormalities. Specifically, it was found that if a temperature abnormality is detected by simply comparing the sensor measurement value with a certain threshold value, depending on the type of substrate or plasma processing, the threshold value may be exceeded even when no substrate temperature abnormality has occurred, which could lead to a false detection of a temperature abnormality. In response to this, the method focused on the time rate of change of the sensor measurement value and determined that a substrate temperature abnormality has occurred when it exceeds a first threshold value. It was found that, depending on the type of plasma processing, the time rate of change may temporarily exceed the first threshold value even when no substrate temperature abnormality has occurred, which could also lead to a false detection of a temperature abnormality. Further research revealed that by determining that a substrate temperature abnormality has occurred when the time rate of change of the sensor measurement value exceeds the first threshold value for a sustained period of time beyond the threshold value, it is possible to appropriately detect a substrate temperature abnormality while avoiding false detection of a temperature abnormality.

[0016] The determination unit may perform a second determination process to determine that a temperature abnormality has occurred in the substrate when the measured value exceeds a second threshold. By performing such a second determination process, assuming that the first determination process is performed, the accuracy of detecting a temperature abnormality in the substrate can be further improved. That is, a temperature abnormality in which the measured value of the sensor (or the temperature of the substrate) continues to rise slowly cannot be detected by the first determination process, but by performing the second determination process, such a type of temperature abnormality can be detected without fail. The second threshold may be, for example, 80°C or higher when the measured value is converted into the temperature of the substrate.

[0017] The plasma processing apparatus may further include a plasma generating unit that generates plasma in the chamber, a gas supply unit that supplies a raw material gas for the plasma into the chamber, and an operation control unit that controls the plasma generating unit and the gas supply unit. The operation control unit may control the plasma generating unit and the gas supply unit to perform a switching operation to generate a second plasma different from the first plasma in the chamber after generating a first plasma in the chamber. The determination unit may perform a first determination process during a period including the timing of the switching operation. In this configuration, the first determination process can appropriately detect an abnormal temperature of the substrate while avoiding false detection during a period including the timing of the switching operation, i.e., a period during which measured values ​​may fluctuate significantly even during normal operation. The operation control unit may be included in a control device provided in the plasma processing apparatus.

[0018] The operation control unit may control the plasma generation unit and the gas supply unit to repeat a unit process including a plurality of steps. The determination unit may perform a first determination process during a period including a period during which the unit process is repeated. In this configuration, the first determination process makes it possible to appropriately detect an abnormal temperature of the substrate while avoiding false detection during the period during which the unit process is repeated, i.e., during a period during which the measured value may repeatedly fluctuate significantly even during normal operation.

[0019] The unit process may include a deposition step of depositing a protective film on the surface of the substrate, a protective film removal step of removing a portion of the protective film to expose a portion of the substrate, and an etching step of etching the exposed portion of the substrate. By repeating such unit processes, the substrate can be deeply engraved using the so-called Bosch process. Furthermore, according to the first determination process, even when the Bosch process is performed, i.e., even when the measured value repeatedly fluctuates significantly in a short period of time, it is possible to appropriately detect an abnormal temperature of the substrate while avoiding false detection.

[0020] The threshold time may be longer than the shortest processing time among the processing times of the multiple steps. For example, if the shortest processing time is 2 seconds, the threshold time may be 2.5 seconds or more and 5 seconds or less.

[0021] (Plasma treatment method) The plasma processing method according to the present disclosure may be performed in the plasma processing apparatus described above, but can also be performed in a plasma processing apparatus that does not include a determination unit. The plasma processing method is a method performed in a plasma processing apparatus that includes the above-described stage and the above-described sensor, and includes a first determination step.

[0022] In the first determination step, if the time rate of change of the measured value output by the sensor exceeds a first threshold and continues to exceed the threshold time, it is determined that a temperature abnormality has occurred in the substrate. This makes it possible to detect a temperature abnormality in the substrate with high accuracy. If the plasma processing apparatus includes the above-mentioned determination unit, the first determination step may be performed by the determination unit. On the other hand, if the plasma processing apparatus does not include the above-mentioned determination unit, the first determination step may be performed by a device (e.g., an information processing device) separate from the plasma processing apparatus.

[0023] The plasma processing method may further include a second determination step of determining that a temperature abnormality has occurred in the substrate when the measured value exceeds a second threshold, thereby further improving the accuracy of detecting a temperature abnormality in the substrate.

[0024] The plasma processing apparatus may further include a plasma generating unit that generates plasma in the chamber and a gas supply unit that supplies a raw material gas for the plasma into the chamber. The plasma processing method may further include an operation control step of controlling the plasma generating unit and the gas supply unit to perform a switching operation to generate a second plasma different from the first plasma in the chamber after generating a first plasma in the chamber. The first determination step may be performed during a period including the timing of the switching operation. In this configuration, the first determination step can appropriately detect a temperature abnormality of the substrate while avoiding false detection during a period including the timing of the switching operation, i.e., a period during which measured values ​​may fluctuate significantly even during normal operation.

[0025] In the operation control step, the plasma generating unit and the gas supply unit may be controlled so as to repeat a unit process including a plurality of steps. The first determination step may be performed during a period including the period during which the unit process is repeated. In this configuration, in the first determination step, during the period during which the unit process is repeated, i.e., during the period during which the measured value may repeatedly fluctuate significantly even during normal operation, it is possible to appropriately detect an abnormal temperature of the substrate while avoiding false detection.

[0026] The unit process may include a deposition step of depositing a protective film on the surface of the substrate, a protective film removal step of removing a part of the protective film to expose a part of the substrate, and an etching step of etching the exposed part of the substrate. In this configuration, even when the Bosch process is performed in the first determination step, that is, even when the measured value fluctuates significantly and repeatedly in a short period of time, it is possible to appropriately detect an abnormal temperature of the substrate while avoiding false detection.

[0027] The threshold time may be longer than the shortest processing time among the processing times of the multiple steps. For example, if the shortest processing time is 2 seconds, the threshold time may be 2.5 seconds or more and 5 seconds or less.

[0028] As described above, according to the present disclosure, by devising a way of using the measurement value output by the sensor, it is possible to detect temperature abnormalities in the substrate with high accuracy.

[0029] An example of a plasma processing apparatus and a plasma processing method according to the present disclosure will be described in detail below with reference to the drawings. The above-described components and processes 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-described embodiment. 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 the present disclosure may be omitted. Note that the diagrams shown below are schematic and do not accurately reflect the shapes and numbers of actual components.

[0030] (Plasma processing equipment) The plasma processing apparatus 10 of this embodiment is an apparatus for plasma processing a substrate (e.g., a semiconductor substrate) as a processing object. The plasma processing apparatus 10 of this embodiment is a plasma dicer, but is not limited to this. As shown in FIG. 1, the plasma processing apparatus 10 includes a stage 11, a chamber 12, a first dielectric member 13, a cover 14, a second dielectric member 15, a first induction coil 16, a second induction coil 17, a first high-frequency power supply 18, a second high-frequency power supply 19, a sensor 23, a gas supply unit 24, and a controller 30.

[0031] The stage 11 is an element on which a substrate (not shown) is placed. The stage 11 has a horizontal mounting surface 11a on which the substrate is placed. The stage 11 has a flow path (not shown) through which a coolant flows to cool the substrate during plasma processing. The stage 11 has an electrostatic adsorption mechanism (not shown) for adsorbing the substrate. The stage 11 has a lower electrode (not shown) to which high-frequency power is applied. Note that temperature abnormalities in the substrate can occur, for example, when the electrostatic adsorption mechanism does not properly adsorb the substrate.

[0032] The chamber 12 accommodates the stage 11 and has a first opening 12a at the top. The chamber 12 is formed in a hollow cylindrical shape, but is not limited to this. The first opening 12a opens upward. The chamber 12 is disposed on the outer periphery side of the stage 11 and has an exhaust port 12b for exhausting the source gas used in the plasma processing. An exhaust device (not shown) is connected to this exhaust port 12b. The chamber 12 is made of a conductive material (e.g., metal) and is grounded.

[0033] The first dielectric member 13 closes the first opening 12a to form a first space S1 inside the chamber 12, and also has a second opening 13a. The first dielectric member 13 is formed in the shape of a horizontally extending plate. The first space S1 is a space in which the stage 11 is disposed. The second opening 13a passes through the first dielectric member 13 from top to bottom. The second opening 13a is disposed in the center of the first dielectric member 13. The first dielectric member 13 has a recess 13b on its upper surface. The first dielectric member 13 is made of quartz, but is not limited to this.

[0034] Cover 14 is provided to cover the lower surface of first dielectric member 13. Cover 14 has first gas inlet passage 14b, which supplies source gas to a region of first space S1 facing first induction coil 16, and second gas inlet passage 14c, which supplies source gas to a region of first space S1 facing second induction coil 17. First gas inlet passage 14b and second gas inlet passage 14c are each formed as grooves or recesses on the upper surface of cover 14. First gas inlet passage 14b communicates with the outside of chamber 12 and communicates with first space S1 via first gas hole 14d. Second gas inlet passage 14c communicates with the outside of chamber 12 and communicates with first space S1 via second gas hole 14e. A plurality of first gas holes 14d and a plurality of second gas holes 14e are arranged at intervals in the circumferential direction. The first gas holes 14d and the second gas holes 14e are each arranged at intervals in the radial direction (left-right direction in FIG. 1). The first gas inlet passage 14b and the second gas inlet passage 14c are each formed between the cover 14 and the first dielectric member 13. A source gas is supplied to the first gas inlet passage 14b and the second gas inlet passage 14c from the gas supply unit 24. The cover 14 has a third opening 14a overlapping with the second opening 13a. The third opening 14a is located in the center of the cover 14. The cover 14 is made of aluminum nitride, but is not limited to this.

[0035] The second dielectric member 15 forms a second space S2 that communicates with the first space S1 via the second opening 13a and the third opening 14a and extends upward beyond the first dielectric member 13. The second dielectric member 15 fits into the second opening 13a and the third opening 14a. The second dielectric member 15 is formed in a cylindrical shape that extends vertically. The second dielectric member 15 is made of aluminum nitride, but is not limited to this.

[0036] The second dielectric member 15 has a dielectric window 15a at its top for optical measurement. The dielectric window 15a transmits infrared rays and other light emitted from the substrate placed on the stage 11. The dielectric window 15a may be integrated with the cylindrical portion of the second dielectric member 15 or may be a separate member.

[0037] The first induction coil 16 extends from the center to the outer periphery of the first dielectric member 13 above the first dielectric member 13 and generates plasma for processing substrates. Each first induction coil 16 is composed of one or more conductors extending spirally in the circumferential direction. A portion of the outer periphery of the first induction coil 16 is disposed inside a recess 13b formed in the first dielectric member 13. The first induction coil 16 receives high-frequency power from the first high-frequency power supply 18 and generates a magnetic field. This magnetic field acts on the source gas in the first space S1 via the first dielectric member 13, generating plasma.

[0038] The second induction coil 17 is disposed to surround the second dielectric member 15 and generates plasma for processing the substrate. The second induction coil 17 has a portion that extends vertically along the second dielectric member 15 and a portion that extends horizontally along the first dielectric member 13. The former is configured as a spiral extending vertically, while the latter is configured as a whorl (spiral) extending horizontally. The second induction coil 17 is disposed on the inner circumferential side of the first induction coil 16. The second induction coil 17 receives high-frequency power from the second high-frequency power supply 19 and generates a magnetic field. This magnetic field acts on the source gas in the first space S1 and / or the second space S2 via the second dielectric member 15, generating plasma.

[0039] First high frequency power supply 18 supplies high frequency power (e.g., AC power of 3 to 30 MHz) to first induction coil 16. First high frequency power supply 18 is connected to one end of first induction coil 16 via first matching box 21 such as a variable capacitor. The other end of first induction coil 16 is grounded via conductive chamber 12.

[0040] Second high frequency power supply 19 supplies high frequency power (e.g., AC power of 3 to 30 MHz) to second induction coil 17. Second high frequency power supply 19 is connected to one end of second induction coil 17 via second matching box 22 such as a variable capacitor. The other end of second induction coil 17 is grounded via conductive chamber 12.

[0041] The frequency of the power from first high frequency power supply 18 (power applied to first induction coil 16) and the frequency of the power from second high frequency power supply 19 (power applied to second induction coil 17) are different from each other. However, both frequencies may be the same. Alternatively, instead of first high frequency power supply 18 and second high frequency power supply 19, a single high frequency power supply may be provided and its power may be distributed to first induction coil 16 and second induction coil 17.

[0042] The first induction coil 16, the second induction coil 17, the first high frequency power supply 18, and the second high frequency power supply 19 constitute a plasma generating unit of this embodiment.

[0043] The sensor 23 is provided above the dielectric window 15a and receives infrared rays emitted from the substrate placed on the stage 11. The sensor 23 outputs a measurement value (hereinafter simply referred to as a measurement value) corresponding to the intensity of the received infrared rays. Information regarding the measurement value is sent to the controller 30 via wired or wireless communication.

[0044] The gas supply unit 24 supplies a plasma raw material gas into the chamber 12. The gas supply unit 24 is connected to the first gas inlet path 14b and the second gas inlet path 14c via gas piping (not shown). The gas supply unit 24 is configured to be able to switch the type of raw material gas to be supplied, thereby making it possible to switch the type of plasma generated in the chamber 12.

[0045] The controller 30 has a determination unit 31 and an operation control unit 32. The controller 30 includes an arithmetic unit and a storage device storing a program executable by the arithmetic unit (e.g., a program for executing the plasma processing method of the present embodiment). The controller 30 is configured to fulfill the functions of the determination unit 31 and the operation control unit 32 by causing the arithmetic unit to execute the program.

[0046] The determination unit 31 determines whether or not a temperature abnormality has occurred on the substrate based on the measurement value T output by the sensor 23. That is, the determination unit 31 performs a first determination process in which it determines that a temperature abnormality has occurred on the substrate when the time rate of change ΔT of the measurement value T exceeds a first threshold ΔT_th and continues to do so for a period exceeding a threshold time t_th. The determination unit 31 also performs a second determination process in which it determines that a temperature abnormality has occurred on the substrate when the measurement value T exceeds a second threshold T_th. In this embodiment, the second determination process is performed when a temperature abnormality on the substrate is not detected in the first determination process. If a temperature abnormality on the substrate is detected in the first or second determination process, it is determined that a temperature abnormality has occurred on the substrate. On the other hand, if a temperature abnormality on the substrate is not detected in the first or second determination process, it is determined that a temperature abnormality on the substrate has not occurred. The first and second determination processes may be performed in real time at predetermined time intervals (e.g., every second) during plasma processing. The threshold time t_th in this embodiment is longer than the processing time of the shortest step among the deposition step, protective film removal step, and etching step, which will be described later.

[0047] Operation control unit 32 controls the plasma generation unit (more specifically, first high-frequency power supply 18 and second high-frequency power supply 19) and gas supply unit 24. That is, operation control unit 32 controls the plasma generation unit and gas supply unit 24 to perform a switching operation to generate a second plasma different from the first plasma in chamber 12 after generating a first plasma in chamber 12. For example, the first plasma and the second plasma can be generated in chamber 12 by changing the outputs of first high-frequency power supply 18 and second high-frequency power supply 19 and the type and flow rate of the raw material gas supplied by gas supply unit 24.

[0048] More specifically, the operation control unit 32 controls the plasma generation unit and the gas supply unit 24 to perform the Bosch process. That is, the operation control unit 32 controls the plasma generation unit and the gas supply unit 24 to repeat a unit process including a deposition step of depositing a protective film on the surface of the substrate, a protective film removal step of removing a portion of the protective film to expose a portion of the substrate, and an etching step of etching the exposed portion of the substrate. The plasma used in the deposition step is an example of a first plasma, the plasma used in the protective film removal step is an example of a second plasma, and the plasma used in the etching step is an example of a third plasma. That is, the switching operation of this embodiment includes a first switching operation from the first plasma to the second plasma, a second switching operation from the second plasma to the third plasma, and a third switching operation from the third plasma to the first plasma. Furthermore, in this embodiment, the first to third switching operations are repeated until the unit process is repeated a predetermined number of times.

[0049] The determination unit 31 performs the first determination process during a period that includes the period during which the unit process is repeated. In other words, the first determination process is performed continuously at predetermined time intervals while the unit process is repeatedly executed. Therefore, the first determination process is performed during a period that includes the timing at which the switching operations (in this example, the first to third switching operations) are performed.

[0050] (Plasma treatment method) The plasma processing method of this embodiment can be performed, for example, in the plasma processing apparatus 10 of this embodiment, and includes an operation control step, a first determination step, and a second determination step.

[0051] In the operation control step, the operation control unit 32 controls the plasma generating unit and the gas supply unit 24 so as to repeat a unit process including a deposition step, a protective film removal step, and an etching step. Note that the operation control step is preferably started after the start of the first determination step.

[0052] When each step is performed normally without any abnormality in the substrate temperature, the relationship between the measured value T (or the substrate temperature) and the processing time is, for example, as shown in the graph in Figure 2. When an abnormality in the substrate temperature occurs, the relationship between the measured value T and the processing time is, for example, as shown in the graph in Figure 3 or Figure 4. Note that the graphs in Figures 3 and 4 do not correspond to plasma processing in which unit processes are repeatedly performed.

[0053] In the first determination step, the determination unit 31 performs the first determination process described above. In the example of FIG. 2, although the time rate of change ΔT of the measurement value T temporarily exceeds the first threshold value ΔT_th, the duration of this state is shorter than the threshold time t_th, so that a temperature abnormality of the substrate is not detected in the first determination step, and plasma processing is continued. On the other hand, in the example of FIG. 3, the state in which the time rate of change ΔT of the measurement value T exceeds the first threshold value ΔT_th continues beyond the threshold time t_th, so that a temperature abnormality of the substrate is detected at time te in the first determination step, and plasma processing is interrupted. Also, in the example of FIG. 4, although the time rate of change ΔT of the measurement value T temporarily exceeds the first threshold value ΔT_th, the duration of this state is shorter than the threshold time t_th, so that a temperature abnormality of the substrate is not detected in the first determination step, and plasma processing is continued.

[0054] In the second determination step, the determination unit 31 performs the second determination process described above. In the example of FIG. 2, the measured value T increases with each unit process, but its maximum value is less than the second threshold value T_th. Therefore, no abnormal substrate temperature is detected in the second determination step, and plasma processing continues. On the other hand, in the example of FIG. 3, the measured value T exceeds the second threshold value T_th, but this timing is later than the timing (time te) at which the abnormal substrate temperature is detected in the first determination step. Therefore, in the example of FIG. 3, the plasma processing is actually interrupted in response to the occurrence of an abnormal substrate temperature in the first determination step before the second determination step is performed. Also, in the example of FIG. 4, the measured value T exceeds the second threshold value T_th. Therefore, a temperature abnormality in the substrate is detected at time te in the second determination step, and plasma processing is interrupted at time te. Note that the second determination step may be performed only if no abnormal substrate temperature is detected in the first determination step, or may be performed regardless of the determination result in the first determination step.

[0055] <<Notes>> The above description of the embodiments discloses the following techniques. (Technology 1) a chamber; a stage provided in the chamber and on which a substrate is placed; a sensor that receives infrared rays emitted from the substrate placed on the stage and outputs a measurement value according to the intensity of the received infrared rays; a determination unit that determines whether or not there is a temperature abnormality in the substrate based on the measurement value; Equipped with The determination unit performs a first determination process to determine that a temperature abnormality has occurred in the substrate when the state in which the time change rate of the measurement value exceeds a first threshold continues beyond a threshold time. (Technology 2) The plasma processing apparatus according to Technology 1, wherein the determining unit performs a second determining process of determining that a temperature abnormality has occurred in the substrate when the measured value exceeds a second threshold value. (Technology 3) a plasma generating unit that generates plasma in the chamber; a gas supply unit that supplies a plasma source gas into the chamber; an operation control unit that controls the plasma generating unit and the gas supply unit; Furthermore, the operation control unit controls the plasma generating unit and the gas supply unit to perform a switching operation of generating a second plasma different from the first plasma in the chamber after generating a first plasma in the chamber; 3. The plasma processing apparatus according to claim 1, wherein the determining unit performs the first determining process during a period including a timing when the switching operation is performed. (Technology 4) the operation control unit controls the plasma generating unit and the gas supply unit so as to repeat a unit process including a plurality of steps; 4. The plasma processing apparatus according to claim 3, wherein the determining unit performs the first determining process during a period including a period during which the unit process is repeated. (Technology 5) The unit process includes: a deposition step of depositing a protective film on the surface of the substrate; a protective film removing step of removing a portion of the protective film to expose a portion of the substrate; an etching step of etching the exposed portion of the substrate; The plasma processing apparatus according to claim 4, comprising: (Technology 6) 6. The plasma processing apparatus according to claim 4, wherein the threshold time is longer than the shortest processing time among the processing times of the plurality of steps. (Technology 7) a chamber; a stage provided in the chamber and on which a substrate is placed; a sensor that receives infrared rays emitted from the substrate placed on the stage and outputs a measurement value according to the intensity of the received infrared rays; A plasma processing method performed in a plasma processing apparatus, comprising: The plasma processing method includes a first determination step of determining that an abnormal temperature of the substrate has occurred when the state in which the time rate of change of the measurement value exceeds a first threshold continues for more than a threshold time. (Technology 8) The plasma processing method according to technique 7 further comprises a second determination step of determining that a temperature abnormality has occurred in the substrate when the measured value exceeds a second threshold value. (Technology 9) The plasma processing apparatus includes: a plasma generating unit that generates plasma in the chamber; a gas supply unit that supplies a plasma source gas into the chamber; Furthermore, The plasma processing method includes: an operation control step of controlling the plasma generating unit and the gas supply unit so as to perform a switching operation of generating a second plasma different from the first plasma in the chamber after generating a first plasma in the chamber, 9. The plasma processing method according to claim 7, wherein the first determination step is performed during a period including a timing at which the switching operation is performed. (Technology 10) In the operation control step, the plasma generating unit and the gas supply unit are controlled so as to repeat a unit process including a plurality of steps; 10. The plasma processing method according to claim 9, wherein the first determination step is performed during a period including a period during which the unit process is repeated. (Technology 11) The unit process includes: a deposition step of depositing a protective film on the surface of the substrate; a protective film removing step of removing a portion of the protective film to expose a portion of the substrate; an etching step of etching the exposed portion of the substrate; The plasma processing method according to technology 10, comprising: (Technology 12) 12. The plasma processing method according to claim 10, wherein the threshold time is longer than the shortest processing time among the processing times of the plurality of steps. [Industrial Applicability]

[0056] The present disclosure can be used in a plasma processing apparatus and a plasma processing method. [Explanation of symbols]

[0057] 10: Plasma processing equipment 11: Stage 11a: Placement surface 12: Chamber 12a: 1st opening 12b: Exhaust port 13: First dielectric member 13a: 2nd opening 13b: Recess 14: Cover 14a: Third opening 14b: First gas inlet 14c: Second gas inlet 14d: First gas hole 14e: Second gas hole 15: Second dielectric member 15a: Dielectric window 16: First induction coil (plasma generation section) 17: Second induction coil (plasma generation section) 18: First high frequency power supply (plasma generation part) 19: Second high frequency power supply (plasma generation part) 21: 1st matching box 22:Second matching box 23: Sensor 24: Gas supply unit 30: Controller 31: Judgment part 32: Operation control unit S1: 1st space S2:Second space T: Measured value (substrate temperature) T_th: Second threshold ΔT: Time rate of change of the measured value ΔT_th: First threshold t_th: threshold time

Claims

1. a chamber; a stage provided in the chamber and on which a substrate is placed; a sensor that receives infrared rays emitted from the substrate placed on the stage and outputs a measurement value according to the intensity of the received infrared rays; a determination unit that determines whether or not there is a temperature abnormality in the substrate based on the measurement value; Equipped with The determination unit performs a first determination process to determine that a temperature abnormality has occurred on the substrate when the time rate of change of the measurement value exceeds a first threshold value for a period of time that continues beyond the threshold value.

2. The plasma processing apparatus according to claim 1 , wherein the determining unit performs a second determining process of determining that a temperature abnormality has occurred in the substrate when the measured value exceeds a second threshold value.

3. a plasma generating unit that generates plasma in the chamber; a gas supply unit that supplies a plasma source gas into the chamber; an operation control unit that controls the plasma generating unit and the gas supply unit; Furthermore, the operation control unit controls the plasma generating unit and the gas supply unit to perform a switching operation of generating a first plasma in the chamber and then generating a second plasma different from the first plasma in the chamber; The plasma processing apparatus according to claim 1 , wherein the determining unit performs the first determining process during a period including a timing when the switching operation is performed.

4. the operation control unit controls the plasma generating unit and the gas supply unit so as to repeat a unit process including a plurality of steps; The plasma processing apparatus according to claim 3 , wherein the determining unit performs the first determining process during a period that includes a period during which the unit process is repeated.

5. The unit process includes: a deposition step of depositing a protective film on the surface of the substrate; a protective film removing step of removing a portion of the protective film to expose a portion of the substrate; an etching step of etching the exposed portion of the substrate; The plasma processing apparatus of claim 4 , comprising:

6. The plasma processing apparatus according to claim 4 , wherein the threshold time is longer than the shortest processing time among the processing times of the plurality of steps.

7. a chamber; a stage provided in the chamber and on which a substrate is placed; a sensor that receives infrared rays emitted from the substrate placed on the stage and outputs a measurement value according to the intensity of the received infrared rays; A plasma processing method performed in a plasma processing apparatus, comprising: The plasma processing method includes a first determination step of determining that an abnormal temperature of the substrate has occurred when the state in which the time rate of change of the measurement value exceeds a first threshold continues for more than a threshold time.

8. 8. The plasma processing method according to claim 7, further comprising a second determining step of determining that a temperature abnormality has occurred in the substrate when the measured value exceeds a second threshold value.

9. The plasma processing apparatus includes: a plasma generating unit that generates plasma in the chamber; a gas supply unit that supplies a plasma source gas into the chamber; Furthermore, The plasma processing method includes: an operation control step of controlling the plasma generating unit and the gas supply unit so as to perform a switching operation of generating a second plasma different from the first plasma in the chamber after generating a first plasma in the chamber; 9. The plasma processing method according to claim 7, wherein the first determination step is performed during a period including a timing at which the switching operation is performed.

10. In the operation control step, the plasma generating unit and the gas supply unit are controlled so as to repeat a unit process including a plurality of steps; The plasma processing method according to claim 9 , wherein the first determination step is performed during a period that includes a period during which the unit process is repeated.

11. The unit process includes: a deposition step of depositing a protective film on the surface of the substrate; a protective film removing step of removing a portion of the protective film to expose a portion of the substrate; an etching step of etching the exposed portion of the substrate; The plasma processing method of claim 10 , comprising:

12. The plasma processing method of claim 10 , wherein the threshold time is longer than the shortest processing time among the processing times of the plurality of steps.

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