Plasma processing apparatus and method for controlling plasma processing apparatus

Abstract

The invention provides a plasma processing apparatus capable of appropriately detecting the temperature of a substrate. A plasma processing apparatus (1) is provided with an antenna (7), a high-frequency power source (8) for intermittently generating plasma by periodically increasing and decreasing the magnitude of a high-frequency current, and at least one detection unit (D) for detecting the temperature of a substrate (W), the detection unit detecting the temperature of the substrate in synchronization with the quenching of the plasma.

Description

Technical Field

[0001] The present invention relates to a plasma processing device and a control method for the plasma processing device. Background Art

[0002] Plasma processing apparatuses are known that generate plasma within a processing chamber (vacuum container) to perform plasma processing on a substrate. For example, Patent Document 1 discloses an inductively coupled plasma processing apparatus that generates an inductively coupled plasma by passing a high-frequency current through an antenna and controls the plasma density within the processing chamber by temporally modulating the high-frequency power supplied to the processing chamber.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Publication No. 2002-538618 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] However, the above-mentioned conventional technology does not have the technical concept of detecting the temperature of the substrate, etc. Therefore, there is room for improvement from the perspective of improving product quality and yield.

[0008] An object of one aspect of the present invention is to provide a plasma processing apparatus capable of appropriately detecting the temperature of a substrate.

[0009] Technical means to solve the problem

[0010] In order to solve the above-mentioned problem, a plasma processing apparatus according to one embodiment of the present invention is a plasma processing apparatus for processing a substrate using plasma, the plasma processing apparatus comprising: a vacuum vessel; a plasma generating unit for generating plasma within the vacuum vessel; a high-frequency power supply for supplying a high-frequency current to the plasma generating unit; an observation window provided in the vacuum vessel; and a detection unit for detecting the temperature of the substrate through the observation window. The high-frequency power supply intermittently generates the plasma by periodically increasing and decreasing the magnitude of the high-frequency current, and the detection unit detects the temperature of the substrate synchronously with the extinction of the plasma.

[0011] To solve the above-mentioned problem, a control method for a plasma processing apparatus according to one embodiment of the present invention is a control method for a plasma processing apparatus that uses plasma to process a substrate, wherein the plasma processing apparatus includes: a vacuum vessel; a plasma generating unit that generates plasma within the vacuum vessel; a high-frequency power supply that supplies a high-frequency current to the plasma generating unit; an observation window disposed in the vacuum vessel; and a detection unit that detects the temperature of the substrate through the observation window. The control method for the plasma processing apparatus includes: a plasma generating step of intermittently generating the plasma by periodically increasing and decreasing the magnitude of the high-frequency current using the high-frequency power supply; and a detection step of detecting the temperature of the substrate synchronously with the extinction of the plasma using the detection unit.

[0012] Effects of the Invention

[0013] According to one aspect of the present invention, the temperature of the substrate can be appropriately detected. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] [ Figure 1 ] is a front cross-sectional view of the plasma processing device according to embodiment 1 of the present invention.

[0015] [ Figure 2 ] is a side sectional view of the plasma processing device.

[0016] [ Figure 3 ] is a diagram showing an example of the waveform of the high-frequency current supplied to the antenna by the high-frequency power supply of the plasma processing device.

[0017] [ Figure 4 ] is a functional block diagram showing the main structure of the monitoring device of the plasma processing device.

[0018] [ Figure 5 ] is a diagram illustrating an example of a method for controlling the temperature of a substrate.

[0019] [ Figure 6 ] is a graph showing the film forming speed and substrate temperature relative to the duty cycle of the high-frequency current.

[0020] [ Figure 7 ] is a front cross-sectional view of a plasma processing device according to a second embodiment of the present invention.

[0021] [ Figure 8 ] is a side sectional view of the plasma processing device. DETAILED DESCRIPTION

[0022] [Implementation Method 1]

[0023] Figure 1This is a front cross-sectional view of the plasma processing apparatus 1 cut along a cutting plane including a certain antenna 7 . Figure 2 This is a side sectional view of the plasma processing apparatus 1 cut along a plane perpendicular to the directions in which the plurality of antennas 7 extend. Figure 2 In the figure, some components (high frequency power supply 8) are omitted. Figure 1 、 Figure 2 The schematic structure of the plasma processing apparatus 1 will be described below.

[0024] <Structure of Plasma Processing Apparatus 1>

[0025] like Figure 1 As shown, plasma processing apparatus 1 includes a housing 2, a flange 3, a vacuum cover 4, an antenna cover 5, a stage 6, an antenna 7 (plasma generating unit), a high-frequency power supply 8, and a monitoring device 20. In plasma processing apparatus 1, a high-frequency voltage is applied from high-frequency power supply 8 to antenna 7, causing a high-frequency current to flow through antenna 7. This generates an induced electric field within housing 2, generating an inductively coupled plasma. Plasma processing apparatus 1 uses this inductively coupled plasma to perform a predetermined plasma process on a substrate W (a sample to be processed) disposed within housing 2.

[0026] Here, the substrate W is, for example, a substrate for a flat panel display (FPD) such as a liquid crystal display or an organic electroluminescence (EL) display, or a flexible substrate. Furthermore, the plasma treatment applied to the substrate W includes, for example, film formation using plasma CVD (chemical vapor deposition), etching, ashing, sputtering, and the like.

[0027] In addition, the plasma processing device 1 is also called a plasma CVD device when film formation is performed by the plasma CVD method, is also called a plasma etching device when etching is performed, is also called a plasma ashing device when ashing is performed, and is also called a plasma sputtering device when sputtering is performed.

[0028] like Figure 2As shown, a plurality of antennas 7 are arranged in an array in the plasma processing apparatus 1. The vacuum cover 4 and antenna cover 5 described later are provided for each antenna 7. Hereinafter, in the plasma processing apparatus 1, the side where the plurality of antennas 7 are provided is referred to as the upper side, and the side where the carrier 6 is provided is referred to as the lower side. Furthermore, the directions in which the plurality of antennas 7 extend are referred to as the left-right direction, and the direction in which the plurality of antennas 7 are arranged is referred to as the front-back direction. Furthermore, in this embodiment, an example in which four antennas 7 are provided in the plasma processing apparatus 1 is shown, but the number of antennas 7 is not limited to this.

[0029] <Case 2>

[0030] The housing 2 includes a housing body 2a constituting a processing chamber for performing the predetermined plasma processing on the substrate W. The housing body 2a is a box-shaped member with an open top.

[0031] A flange 3 having multiple openings is airtightly attached to the opening of the housing body 2a (housing opening 2b). The multiple openings of the flange 3 are blocked by a vacuum cover 4. In other words, when the flange 3 and vacuum cover 4 are attached to the upper surface of the housing 2, the housing opening 2b is blocked by the flange 3 and vacuum cover 4. Thus, by airtightly attaching the flange 3 and vacuum cover 4 to the housing body 2a and flange 3, respectively, the housing 2 forms a vacuum container containing the processing chamber.

[0032] Furthermore, by installing an antenna cover 5 (described later) within the housing opening 2b, the interior space of the housing 2 is demarcated, forming a plasma generation area HA within the housing body 2a. A stage 6 and a substrate W supported thereon are disposed within the plasma generation area HA, essentially forming the processing chamber. In other words, within the housing 2, the antenna cover 5 separates the plasma generation area HA from a plasma non-generating area (antenna accommodation space AK, described later).

[0033] In addition, if Figure 1 As shown, a vacuum pump PO is connected to the housing body 2a in the housing 2. The interior of the plasma generation area HA is set to a predetermined vacuum degree at least when plasma processing is performed by the vacuum pump PO.

[0034] The housing 2 may also include a process gas supply unit (not shown) that introduces a process gas corresponding to the predetermined plasma process into the interior of the plasma generation area HA (processing chamber) at a predetermined vacuum level. The plasma process is performed in an environment containing the process gas. The process gas may be, for example, argon, hydrogen, nitrogen, silane, methane, oxygen, or nitrogen trifluoride.

[0035] <Flange 3>

[0036] The flange 3 includes, for example, a rectangular frame having two first side portions 3a ( Figure 2 ), and two second sides 3b ( Figure 1 ). Furthermore, the flange 3 may include, for example, a third side portion 3c, a fourth side portion 3d, and a fifth side portion 3e, which are arranged on the inner side of the frame body from one second side portion 3b to the other second side portion 3b. In other words, each end portion of the third side portion 3c, the fourth side portion 3d, and the fifth side portion 3e is formed continuously with the second side portion 3b. The third side portion 3c, the fourth side portion 3d, and the fifth side portion 3e may be formed between the two first side portions 3a so as to be parallel to the first side portions 3a.

[0037] In addition, the first side 3a, the second side 3b, the third side 3c, the fourth side 3d, and the fifth side 3e may each have a protrusion (described later) that protrudes toward the housing opening 2b. Hereinafter, the first side 3a, the second side 3b, the third side 3c, the fourth side 3d, and the fifth side 3e are collectively referred to as side 3h.

[0038] Vacuum cover 4

[0039] Furthermore, in the plasma processing apparatus 1, the vacuum hood 4 that closes the housing opening 2b is configured to be removably mounted on the housing opening 2b. Here, the flange 3 may include a protrusion that is formed to gradually reduce the opening area of the housing opening 2b in a direction from the outside of the processing chamber toward the inside of the processing chamber. For example, the first side 3a, the third side 3c, the fourth side 3d, and the fifth side 3e may each include a first support portion that protrudes from the inside of the housing opening 2b to secure the peripheral edge of the vacuum hood 4. The first support portion may be a portion of the protrusion. Furthermore, the vacuum hood 4 is an example of an outer hood that abuts the upper surface of the second side 3b and is supported by abutting against the upper surface of the first support portion of the first side 3a, the third side 3c, the fourth side 3d, and the fifth side 3e. The vacuum hood 4 is, for example, made of metal.

[0040] <Radome 5>

[0041] In addition, in the plasma processing apparatus 1, the antenna cover 5 is supported inside the housing opening 2b in a manner that is detachable relative to the flange 3. Specifically, Figure 1 and Figure 2 As shown, the radome 5 includes, for example, an antenna housing portion 5a having a U-shaped cross section. Furthermore, the radome 5 includes a cover support portion 5b and a cover opening 5c. The radome 5 is formed using a dielectric material such as alumina and forms a dielectric inner cover.

[0042] The antenna housing portion 5a is formed to correspond to the shape of the antenna 7. The antenna housing portion 5a is configured to have a shape that covers a portion of the outer peripheral surface of the antenna 7 when the antenna 7 is attached.

[0043] The cover support portion 5b is formed continuously from both ends of the antenna housing portion 5a having a U-shaped cross section and is formed as a flange portion so as to protrude outward from the ends of the antenna housing portion 5a.

[0044] Here, for example, the edge 3h of the flange 3 may include a second support portion that protrudes from within the housing opening 2b to engage the peripheral edge of the radome 5. This second support portion is a portion of the protruding portion, and protrudes further into the housing opening 2b than the first support portion (protruding longer). When the radome 5 is supported within the housing opening 2b, the radome support portion 5b is supported by (the second support portion of) the edge 3h of the flange 3.

[0045] The cover opening 5c is an opening formed by being surrounded by the antenna housing portion 5a and is provided so as to open toward the vacuum cover 4 side.

[0046] Furthermore, an antenna housing space AK is formed in the housing 2 and is surrounded by at least a vacuum cover 4 and a radome 5. The antenna housing space AK is an example of an enclosed space and houses an antenna 7 for generating inductively coupled plasma. However, the size of the antenna housing space AK is set to a level that is insufficient to sustain the plasma generated by the antenna 7, and therefore functions as a plasma non-generating region.

[0047] Antenna 7

[0048] like Figure 1 As shown, antenna 7 has a long, straight portion and upwardly curved portions at both ends of the straight portion. Antenna 7 is cylindrical, for example, and is made of a metal material such as copper. Antenna 7 is placed in vacuum housing 4, with one end electrically insulated from vacuum housing 4 by antenna insulating portions 41a and 41b, respectively, and is airtightly extended outside housing 2.

[0049] One end of antenna 7 receives high-frequency power supplied from high-frequency power supply 8. The other end of antenna 7 is electrically grounded. Hereinafter, one end and the other end of antenna 7 are referred to as power-side end 7a and ground-side end 7b, respectively. A matching circuit 9 is connected to power-side end 7a of antenna 7. A variable capacitor VC is connected to ground-side end 7b of antenna 7. Variable capacitor VC is an example of an impedance adjustment unit with variable impedance, but is not limited thereto.

[0050] In addition, a cooler 10 is connected to the antenna 7, and the antenna 7 is cooled to a predetermined temperature by a cooling medium, such as cooling water, that circulates through the cooler 10. Specifically, the cooler 10 includes: a cooler body 10a, which includes a driving unit such as a pump (not shown) for circulating the cooling water; and a pipe 10b, which is airtightly connected to the cooler body 10a. In addition, the pipe 10b is also arranged in the internal space of the antenna 7, and is configured to use the internal space of the antenna 7 as a circulation path for the cooling water. That is, in the antenna 7, as shown in FIG. Figure 1 As indicated by arrows R1 and R2 , the antenna 7 is cooled by causing cooling water to flow through the inner space of the antenna 7 .

[0051] <High-frequency power supply 8>

[0052] The high-frequency power supply 8 supplies, for example, 13.56 MHz high-frequency power to the power supply-side end 7a via the matching circuit 9. Here, the high-frequency power supply 8 intermittently generates plasma by periodically increasing and decreasing the magnitude of the high-frequency current. Specifically, the high-frequency power supply 8 supplies the high-frequency current to the antenna 7, alternating between a first period TA (on period) corresponding to ignition of the plasma and a high-frequency current magnitude of at least a first current value, and a second period TB (off period) corresponding to extinction of the plasma and a high-frequency current magnitude of less than the first current value. By supplying this high-frequency current to the antenna 7, the high-frequency power supply 8 generates plasma in the plasma generation area HA during the first period TA and does not generate plasma in the plasma generation area HA during the second period TB.

[0053] Figure 3 : is a graph showing an example of the waveform of the high-frequency current supplied from the high-frequency power supply 8 to the antenna 7. Figure 3 The diagram is shown for easy understanding when referring to the following description. The ratio of wavelength and amplitude is not accurate. For example, by turning on the high-frequency power supply 8 and supplying high-frequency current to the antenna 7, and then turning off the high-frequency power supply 8 and stopping the high-frequency current, the high-frequency power supply 8 can generate the following Figure 3 A high-frequency current is generated by alternating between current values greater than the first current value and zero current value, as shown. Alternatively, a high-frequency current can be generated by amplitude modulating the high-frequency current based on a predetermined signal wave. Hereinafter, the proportion of the first period TA in the high-frequency current is referred to as the duty cycle of the high-frequency current.

[0054] Detector D

[0055] The plasma processing apparatus 1 further includes a detector D for detecting the temperature of the substrate W through an observation window 11. The detector D is, for example, a radiation thermometer capable of detecting the temperature of the substrate W based on spectral data of electromagnetic waves emitted from the substrate W. The observation window 11 is made of a material with high transmittance to electromagnetic waves emitted from the substrate W, such as barium fluoride, calcium fluoride, or germanium.

[0056] The detector D detects the temperature of the substrate W synchronously with the extinction of the plasma. In other words, the detector D detects the temperature of the substrate W during the second period TB in which the high-frequency current is less than the first current value. This allows the temperature of the substrate W to be detected while the plasma treatment of the surface of the substrate W is ongoing while the plasma is extinguished. This eliminates the need to measure the temperature of the substrate W after the plasma treatment, shortening the overall plasma treatment time and improving productivity. Furthermore, if the temperature of the substrate W is detected while the plasma is ignited, there is a possibility that the detector D will detect infrared radiation from the plasma in addition to electromagnetic waves radiated from the substrate W. By detecting the temperature of the substrate W during the extinction of the plasma, the plasma processing apparatus 1 eliminates this possibility. Therefore, the plasma processing apparatus 1 can appropriately detect the temperature of the substrate W. Furthermore, if the temperature of the substrate W exhibits an abnormal value during the plasma treatment, the plasma treatment can be promptly stopped or other measures can be taken.

[0057] The detector D may be provided at a position facing the surface of the substrate W. Thus, by being arranged above a predetermined position on the surface of the substrate W, the detector D can appropriately detect the temperature of the predetermined position.

[0058] In this embodiment, the detector D is integrally provided on the fourth side 3d of the flange 3. The detector D is arranged in the left-right center of the fourth side 3d. Thus, the detector D can appropriately detect the temperature of the center of the surface of the substrate W.

[0059] In addition, the plasma processing apparatus 1 may also include an illumination unit L for illuminating the interior of the processing chamber. The illumination unit L includes, for example, a light-emitting component such as a lamp or a light-emitting diode (LED), and illuminates the interior of the processing chamber by emitting a predetermined illumination light from the light-emitting component. In this embodiment, the illumination unit L is integrally provided with the detector unit D on the fourth side portion 3d of the flange 3. Thus, the position of the detector unit D can be adjusted while visually confirming the predetermined position on the surface of the substrate W. The plasma processing apparatus 1 also includes a photographing unit for photographing the interior of the processing chamber, and the predetermined position on the surface of the substrate W can be confirmed by the photographing unit.

[0060] <Monitoring device 20>

[0061] Figure 4 2 is a block diagram showing the main structure of the monitoring device 20. Figure 4 As shown, the monitoring device 20 includes an acquisition unit 21 , a storage unit 22 , a control unit 23 , and an output unit 24 .

[0062] The acquisition unit 21 acquires the temperature of the substrate W from the detector D. The acquisition unit 21 stores the temperature of the substrate W in the storage unit 22. The acquisition unit 21 is, for example, a communication interface that communicates with the detector D via a wired or wireless network. The storage unit 22 stores various data used by the monitoring device 20. The output unit 24 outputs various information processed by the monitoring device 20 (e.g., the temperature of the substrate W) to the outside.

[0063] The control unit 23 is a functional block that includes, for example, a central processing unit (CPU), random access memory (RAM), and read-only memory (ROM). It controls various components of the plasma processing apparatus 1 based on information processing. Specifically, the control unit 23 performs predetermined control processing for plasma processing of substrates W in the plasma generation area HA. The control unit 23 includes a power supply control unit 231, a stage control unit 232, and a detection control unit 233.

[0064] The power supply control unit 231 controls the waveform of the high-frequency current supplied by the high-frequency power supply 8 to the antenna 7. Specifically, upon receiving a user instruction to start a plasma processing operation, the power supply control unit 231 controls the high-frequency power supply 8 so that the magnitude of the high-frequency current flowing to the antenna 7 periodically increases or decreases. The power supply control unit 231 then retrieves temperature data related to the temperature of the substrate W (e.g., the current temperature of the substrate W or time-series data of the temperature of the substrate W) from the storage unit 22 and updates the waveform of the high-frequency current based on this temperature data. Thus, the power supply control unit 231 adjusts the temperature of the substrate W. The power supply control unit 231 preferably adjusts the temperature of the substrate W by controlling the ratio (duty cycle) of the first period TA of the high-frequency current. By controlling the duty cycle, the temperature of the substrate W can be adjusted without changing the impedance of the variable capacitor VC. The power supply control unit 231 can also adjust the temperature of the substrate W by adjusting the intensity of the high-frequency current.

[0065] The stage control unit 232 controls the temperature of a heater built into the stage 6 for heating the substrate W. Specifically, the stage control unit 232 acquires temperature data related to the temperature of the substrate W from the storage unit 22 and adjusts the temperature of the heater of the stage 6 based on the temperature data.

[0066] The detection control unit 233 controls the detection timing of the detection unit D based on the waveform of the high-frequency current determined by the power supply control unit 231. Specifically, the detection control unit 233 determines the detection timing of the detection unit D so that the detection unit D detects the temperature of the substrate W in synchronization with the extinction of the plasma. In other words, the detection control unit 233 determines the detection timing of the detection unit D so that the detection unit D detects the temperature of the substrate W during the second period TB.

[0067] also, Figure 4 The control unit 23 shown in the monitoring device 20 is not an essential component. The monitoring device 20 only needs to have at least the function of monitoring the temperature of the substrate W (for example, if the temperature of the substrate W shows an abnormal value during plasma processing, the plasma processing can be stopped or the like). In this case, for example, the user can determine the waveform of the high-frequency current based on the substrate W temperature obtained by the monitoring device 20, or adjust the temperature of the heater of the stage 6.

[0068] In addition, this embodiment describes a case where the detector D for monitoring the temperature of a substrate W is applied to an inductively coupled plasma processing apparatus as an example of a plasma processing apparatus 1. Here, the inductively coupled plasma processing apparatus is an apparatus that processes substrates W using inductively coupled plasma generated by a plurality of antennas 7 as a plasma generating unit. However, the plasma processing apparatus 1 is not limited to this apparatus, and any apparatus that processes substrates W using plasma (e.g., a capacitively coupled plasma processing apparatus) may be used.

[0069] <Operation Example of Plasma Processing Apparatus 1>

[0070] Below, refer to Figure 5 An example of the operation of the plasma processing apparatus 1 according to the first embodiment will be described in detail. Figure 5 This is a diagram illustrating an example of a method for controlling the temperature of a substrate W. Figure 5 In FIG. 5 , the vertical axis corresponds to the left and right axes. The solid line 5A corresponds to the left vertical axis, and the solid line 5B corresponds to the right vertical axis.

[0071] In the plasma processing apparatus 1 of the first embodiment, upon receiving a user's instruction to start a plasma processing operation, the power supply control unit 231 controls the high-frequency power supply 8 to periodically increase and decrease the magnitude of the high-frequency current flowing to the antenna 7. Specifically, the high-frequency power supply 8 supplies the high-frequency current to the antenna 7, alternating between a first period TA corresponding to the lighting of the plasma and a high-frequency current magnitude greater than or equal to a first current value, and a second period TB corresponding to the extinction of the plasma and a high-frequency current magnitude less than the first current value. The magnitude of the high-frequency current during the second period TB may be zero. Thus, the high-frequency power supply 8 intermittently generates plasma in the plasma generation area HA (plasma generation step). That is, the high-frequency power supply 8 generates plasma during the first period TA and does not generate plasma during the second period TB.

[0072] Furthermore, the detection control unit 233 controls the detection unit D to detect the temperature of the substrate W in synchronization with the extinction of the plasma. In other words, the detection unit D detects the temperature of the substrate W during the second period TB (detection step). Consequently, temperature data related to the temperature of the substrate W is stored in the storage unit 22.

[0073] Next, based on the temperature data, the power supply control unit 231 updates the waveform of the high frequency current determined in the plasma generation step. Figure 5 As shown, when the temperature of the substrate W detected by the detector D reaches a first predetermined temperature or higher, the power supply control unit 231 reduces the duty ratio of the high-frequency current supplied to each antenna 7. This suppresses the temperature increase of the substrate W.

[0074] With this configuration, the monitoring device 20 can control the temperature of the substrate W during plasma processing by controlling the waveform of the high-frequency current based on the temperature of the substrate W during plasma processing. This can stabilize product quality and improve yield.

[0075] Furthermore, the stage control unit 232 may adjust the temperature of the heater of the stage 6 based on the temperature data. For example, the stage control unit 232 may lower the temperature of the heater when the temperature of the substrate W reaches or exceeds a first predetermined temperature. This suppresses the temperature increase of the substrate W.

[0076] <Example>

[0077] In the plasma processing apparatus 1, Figure 3 The film formation speed and the temperature of the substrate W when the high-frequency current shown is supplied to the antenna 7 are measured. Figure 6 The figure shows the film forming speed and the temperature of the substrate W relative to the duty ratio of the high frequency current. Here, the stage temperature is set to 150°C ( Figure 6 6A and 6D) or 240°C (in Figure 6 (shown as dashed lines 6B and 6C in the figure), the duty cycle of the high-frequency current is set to 0.5, 0.7, 0.9 or 1. Figure 6 In the figure, the vertical axes correspond to the left and right axes. The dashed line 6C and the solid line 6D correspond to the left vertical axis, and the solid line 6A and the dashed line 6B correspond to the right vertical axis. Furthermore, the film deposition rate on the left vertical axis is calculated based on the film thickness and film deposition time measured using an ellipsometer.

[0078] like Figure 6 As shown by the solid line 6A and the dotted line 6B, the temperature of the substrate W decreases linearly with decreasing duty cycle at any stage temperature. This indicates that the temperature of the substrate W is proportional to the length of the on period regardless of the duty cycle.

[0079] On the other hand, Figure 6 As shown by the dashed line 6C and the solid line 6D, at any stage temperature, the film forming rate decreases linearly with the decrease of the duty cycle ( Figure 6 The value of the on-time is greater than the value shown by the dashed line 6E and the solid line 6F in the figure. This indicates that the film formation rate per unit length of the on-time is increased by reducing the duty cycle. The reason for this is that even when the plasma is extinguished, the remaining radicals contribute to the plasma processing.

[0080] As a result, it was confirmed that by reducing the duty ratio of the high-frequency current during plasma processing, the length of the on-period required for plasma processing can be shortened, thereby reducing the temperature of the substrate W.

[0081] In other words, the duty cycle and film formation speed are not in a purely proportional relationship; while shortening the on-period increases the film formation speed. Therefore, it was confirmed that controlling the duty cycle can achieve a high film formation speed while suppressing the temperature rise on the surface of the substrate W (a phenomenon proportional to the on-period).

[0082] [Implementation Method 2]

[0083] Hereinafter, another embodiment of the present invention will be described. For the sake of convenience, components having the same functions as those described in the above embodiment will be denoted by the same reference numerals, and their description will not be repeated.

[0084] Figure 7 It is a front cross-sectional view of a plasma processing apparatus 1A according to a second embodiment. Figure 81 is a side sectional view of a plasma processing apparatus 1A according to Embodiment 2. The plasma processing apparatus 1A differs from the plasma processing apparatus 1 in that it includes a plurality of detection units D. Hereinafter, the plurality of antennas 7 are referred to as the first antenna 71, the second antenna 72, the third antenna 73, and the fourth antenna 74, respectively, from the front to the rear. In addition, the plasma processing apparatus 1A includes at least two high-frequency power supplies 8. For example, the at least two high-frequency power supplies 8 may also be four high-frequency power supplies provided corresponding to the plurality of antennas 7. For example, the at least two high-frequency power supplies 8 may also be two high-frequency power supplies including a high-frequency power supply for supplying high-frequency current to the first antenna 71 and the second antenna 72, and a high-frequency power supply for supplying high-frequency current to the third antenna 73 and the fourth antenna 74.

[0085] exist Figure 8 In the example shown, the plurality of detectors D include a first detector D1, a second detector D2, and a third detector D3, which are respectively provided on the third side 3c, the fourth side 3d, and the fifth side 3e of the flange 3. The first detector D1 is arranged between the first antenna 71 and the second antenna 72. The second detector D2 is arranged between the second antenna 72 and the third antenna 73. The third detector D3 is arranged between the third antenna 73 and the fourth antenna 74. In addition, as shown in FIG. Figure 7 As shown, two detection units other than the first detection unit D1 , the second detection unit D2 , and the third detection unit D3 may be provided along the left-right direction on each of the third side 3 c , the fourth side 3 d , and the fifth side 3 e .

[0086] The first detection unit D1 detects the temperature of a first position below the first detection unit D1 on the surface of the substrate W. The second detection unit D2 detects the temperature of a second position below the second detection unit D2 on the surface of the substrate W. The third detection unit D3 detects the temperature of a third position below the third detection unit D3 on the surface of the substrate W.

[0087] The acquisition unit 21 acquires the temperatures of the positions corresponding to the detectors D on the surface of the substrate W from the detectors D. The acquisition unit 21 stores the temperatures of the positions corresponding to the detectors D on the substrate W as substrate W temperature distribution data in the storage unit 22 .

[0088] The power supply control unit 231 retrieves temperature distribution data of the substrate W from the storage unit 22 and, based on this temperature distribution data, individually controls the waveforms of the high-frequency currents supplied by the at least two high-frequency power supplies 8 to the multiple antennas 7. The power supply control unit 231 can control the waveforms of the high-frequency currents supplied by the at least two high-frequency power supplies 8 to the multiple antennas 7 to reduce the temperature difference between the first position and the second position. For example, if the temperature at the first position is higher than the temperature at the second position, the power supply control unit 231 reduces the duty cycle of the high-frequency current supplied to the first antenna 71 and the second antenna 72, which are positioned across the first position when viewed from above, to reduce the temperature at the first position. This reduces the temperature at the first position, thereby reducing the temperature difference between the first and second positions.

[0089] This structure makes it possible to uniformly distribute the temperature of the substrate W. This allows for stabilization of product quality and improvement of yield.

[0090] (Summarize)

[0091] A plasma processing apparatus according to a first embodiment of the present invention is a plasma processing apparatus for processing a substrate using plasma, the plasma processing apparatus comprising: a vacuum vessel; a plasma generating unit for generating plasma within the vacuum vessel; a high-frequency power supply for supplying a high-frequency current to the plasma generating unit; an observation window disposed in the vacuum vessel; and a detection unit for detecting the temperature of the substrate via the observation window. The high-frequency power supply intermittently generates the plasma by periodically increasing and decreasing the magnitude of the high-frequency current, and the detection unit detects the temperature of the substrate synchronously with the extinction of the plasma.

[0092] The plasma processing apparatus according to the second embodiment of the present invention, according to the first aspect, further includes a control unit configured to control the waveform of the high-frequency current based on the temperature of the substrate detected by the detection unit.

[0093] The plasma processing device of embodiment 3 of the present invention is based on the form 1, including: multiple plasma generating parts; at least two high-frequency power supplies that supply high-frequency current to the multiple plasma generating parts; and multiple detection parts. The plasma processing device also includes a control part that individually controls the waveforms of the high-frequency current supplied by the at least two high-frequency power supplies to the multiple plasma generating parts based on the temperatures of the substrate detected by the multiple detection parts.

[0094] In the plasma processing device of embodiment 4 of the present invention, according to form 3, the multiple detection parts include: a first detection part, which detects the temperature at a first position of the substrate; and a second detection part, which detects the temperature at a second position of the substrate. The control part controls the waveform of the high-frequency current supplied by the at least two high-frequency power supplies to the multiple plasma generating parts respectively to reduce the difference between the temperature at the first position and the temperature at the second position.

[0095] In the plasma processing apparatus according to the fifth embodiment of the present invention, according to the second to fourth aspects, the control unit controls the ratio of the period during which the high-frequency current is equal to or greater than a first current value, corresponding to the lighting of the plasma.

[0096] In the plasma processing apparatus according to the sixth embodiment of the present invention, according to the first to fifth aspects, the detection portion is provided at a position facing the surface of the substrate.

[0097] The plasma processing apparatus according to a seventh embodiment of the present invention, according to the first to sixth aspects, further includes an illumination unit configured to illuminate the interior of the vacuum container.

[0098] A control method for a plasma processing apparatus according to an eighth embodiment of the present invention is a control method for a plasma processing apparatus that processes a substrate using plasma, wherein the plasma processing apparatus comprises: a vacuum vessel; a plasma generating unit that generates plasma within the vacuum vessel; a high-frequency power supply that supplies a high-frequency current to the plasma generating unit; an observation window disposed in the vacuum vessel; and a detection unit that detects the temperature of the substrate via the observation window. The control method for the plasma processing apparatus includes: a plasma generating step in which the plasma is intermittently generated by periodically increasing and decreasing the magnitude of the high-frequency current using the high-frequency power supply; and a detection step in which the temperature of the substrate is detected by the detection unit in synchronization with the extinction of the plasma.

[0099] [Software-based implementation example]

[0100] The function of the monitoring device 20 (hereinafter referred to as "device") is a program for enabling a computer to function as the device, which can be realized by a program for enabling the computer to function as each control block of the device (especially each unit included in the control unit 23).

[0101] In this case, the apparatus includes a computer having at least one control device (e.g., a processor) and at least one storage device (e.g., a memory) as hardware for executing the program. The functions described in each embodiment are implemented by executing the program using the control device and the storage device.

[0102] The program may be recorded in one or more non-temporary computer-readable recording media. The recording medium may or may not be included in the apparatus. In the latter case, the program may be supplied to the apparatus via any transmission medium, whether wired or wireless.

[0103] Furthermore, some or all of the functions of each control block can be implemented using logic circuits. For example, integrated circuits incorporating logic circuits that function as each control block are also within the scope of the present invention. Furthermore, the functions of each control block can also be implemented using, for example, a quantum computer.

[0104] Furthermore, each process described in the above embodiments may be executed by AI (Artificial Intelligence). In such a case, the AI may be executed by the control device or by another device (e.g., an edge computer or a cloud server).

[0105] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0106] Explanation of Figure Numbers

[0107] 1.1A: Plasma treatment device

[0108] 7: Antenna (plasma generating unit)

[0109] 8: High frequency power supply

[0110] 11: Observation window

[0111] 20: Surveillance Device

[0112] 23: Control Department

[0113] D: Detection Department

[0114] D1: First detection unit

[0115] D2: Second detection unit

[0116] L: Lighting Department

Claims

1. A plasma processing apparatus for processing a substrate using plasma, the plasma processing apparatus comprising: Vacuum container; a plasma generating unit for generating plasma in the vacuum container; a high-frequency power supply for supplying high-frequency current to the plasma generating portion; An observation window is provided in the vacuum container; as well as a detection unit, detecting the temperature of the substrate through the observation window, The high-frequency power supply intermittently generates the plasma by periodically increasing and decreasing the magnitude of the high-frequency current. The detection unit detects the temperature of the substrate in synchronization with the extinction of the plasma. 2 . The plasma processing apparatus according to claim 1 , further comprising a control unit configured to control a waveform of the high-frequency current based on the temperature of the substrate detected by the detection unit.

3. The plasma processing apparatus according to claim 1, comprising: a plurality of said plasma generating parts; At least two of the high-frequency power supplies supply high-frequency current to the plurality of plasma generating parts; as well as a plurality of said detection parts, The plasma processing apparatus further includes a control unit configured to individually control waveforms of the high-frequency currents supplied by the at least two high-frequency power supplies to the plurality of plasma generating units based on the temperatures of the substrate detected by the plurality of detectors.

4. The plasma processing apparatus according to claim 3, wherein: The plurality of detection units include: a first detection unit for detecting the temperature at a first position of the substrate; and a second detection unit for detecting the temperature at a second position of the substrate. The control unit controls the waveforms of the high-frequency currents supplied by the at least two high-frequency power supplies to the plurality of plasma generating units, respectively, to reduce a temperature difference between the first position and the second position.

5. The plasma processing apparatus according to claim 2 or 3, wherein: The control unit controls the ratio of a period in which the magnitude of the high-frequency current is equal to or greater than a first current value, corresponding to lighting of the plasma.

6. The plasma processing apparatus according to claim 1, wherein The detection portion is provided at a position facing the surface of the substrate. 7 . The plasma processing apparatus according to claim 1 , further comprising a lighting unit configured to illuminate the interior of the vacuum container.

8. A method for controlling a plasma processing apparatus, wherein the plasma processing apparatus processes a substrate using plasma, wherein The plasma processing device comprises: Vacuum container; a plasma generating unit for generating plasma in the vacuum container; a high-frequency power supply for supplying high-frequency current to the plasma generating portion; An observation window is provided in the vacuum container; as well as a detection unit for detecting the temperature of the substrate through the observation window, The control method of the plasma processing apparatus includes: a plasma generating step of intermittently generating the plasma by periodically increasing and decreasing the magnitude of the high-frequency current using the high-frequency power supply; as well as The detection step is to detect the temperature of the substrate by the detection unit in synchronization with the extinction of the plasma.

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