Plasma Processing Equipment

Abstract

To provide a plasma processing apparatus capable of accurately detecting a change in a detection position and changing the detection position.SOLUTION: A plasma processing apparatus 1 includes a light projecting unit 81 capable of irradiating the surface of a processed object 100 with light through a window 23, and a light receiving unit 82 that can receive the reflected light that is reflected on the surface of the processed object and emitted through the window. On the periphery of the window, a first inclined surface 23a1 inclined with respect to the central axis of the window, and a second inclined surface 23a2 inclined with respect to the central axis of the window in a direction opposite to the first inclined surface are provided. The light projecting unit faces the first inclined surface. The light receiving unit faces the second inclined surface.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] An embodiment of the present invention relates to a plasma processing apparatus. [Background technology]

[0002] In a plasma processing apparatus used for dry etching, etc., the end point of the plasma processing is detected based on a change in the emission spectrum of the plasma (for example, see Patent Document 1). However, changes in the emission spectrum of the plasma and changes in the scattering intensity of the light irradiated onto the surface of the workpiece result in changes in light over a relatively wide range, and therefore the intensity of the light incident on the sensor that detects the end point is the average value of the light intensity over a relatively wide range, making it difficult to detect slight changes on the surface of the workpiece.

[0003] Also, a technique has been proposed in which a sensor is provided on the side of a chamber and detection light is made incident on a detection position from a direction inclined with respect to the surface of the workpiece (see, for example, Patent Document 2). However, if a sensor is provided on the side of the chamber and the detection light is incident on the detection position from a direction inclined with respect to the surface of the workpiece, the irradiation area of ​​the detection light at the detection position becomes large, and when the irradiation area of ​​the detection light becomes large, information about the surroundings of the detection position is mixed in, making it difficult to detect slight changes at the detection position.

[0004] Furthermore, when a sensor is provided on the side of the chamber, a window for transmitting the detection light must be provided in the side wall of the chamber. However, since the side wall of the chamber is provided with a nozzle for supplying gas into the chamber, a load lock chamber, and the like, the location of the window is limited. Furthermore, a large window cannot be provided in consideration of the airtightness of the chamber. If the location of the window is limited or if a large window cannot be provided, it becomes difficult to change the detection position.

[0005] Therefore, there has been a demand for the development of a plasma processing apparatus that is capable of detecting changes in the detection position with high accuracy and that allows the detection position to be changed. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2007-66935 A [Patent Document 2] Japanese Patent Application Publication No. 7-58081 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a plasma processing apparatus capable of detecting a change in a detection position with high accuracy and capable of changing the detection position. [Means for solving the problem]

[0008] The plasma processing apparatus according to the embodiment includes a chamber capable of maintaining an atmosphere reduced in pressure below atmospheric pressure, a gas supply unit capable of supplying gas to the inside of the chamber, a stage provided in the chamber on which a workpiece can be placed, a pressure reduction unit capable of reducing the pressure inside the chamber, a window provided in the chamber facing the stage, a plasma generation unit provided outside the chamber on the opposite side of the window from the stage and capable of generating plasma inside the chamber, a light projection unit capable of irradiating light onto the surface of the workpiece through the window, and a light receiving unit capable of receiving the reflected light reflected by the surface of the workpiece and emitted through the window. The window is provided at its periphery with a first inclined surface inclined with respect to the central axis of the window, and a second inclined surface inclined with respect to the central axis of the window and inclined in the opposite direction to the first inclined surface. The light projection unit faces the first inclined surface. The light receiving unit faces the second inclined surface. Effect of the Invention

[0009] According to an embodiment of the present invention, a plasma processing apparatus is provided that is capable of detecting a change in a detection position with high accuracy and that allows the detection position to be changed. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view illustrating a plasma processing apparatus according to an embodiment of the present invention. [Diagram 2] 10A to 10C are schematic cross-sectional views for illustrating a detection unit according to a comparative example. [Diagram 3] 13A and 13B are schematic cross-sectional views for illustrating a detection portion according to another comparative example. [Figure 4] 4 is a schematic cross-sectional view illustrating a light projecting portion, a light receiving portion, an inclined surface, and an inclined surface. FIG. [Diagram 5] 1 is a schematic plan view illustrating a light projecting portion, a light receiving portion, an inclined surface, and an inclined surface. FIG. [Figure 6] 11A to 11C are schematic cross-sectional views for illustrating a change in the detection position. [Figure 7] 1 is a schematic diagram illustrating a moving portion; [Figure 8] 8 is a schematic diagram of the moving part in FIG. 7 as viewed from the X direction. [Figure 9] 11 is a schematic diagram for illustrating a guide. FIG. [Figure 10] 11 is a schematic diagram for illustrating a guide. FIG. [Figure 11] 11 is a schematic diagram of the guide in FIG. 10 as viewed from the Z direction. [Figure 12] 13(a) to 13(c) are schematic diagrams illustrating the case. [Figure 13] 1 is a schematic diagram illustrating a plurality of moving parts; [Figure 14] 10A to 10C are schematic diagrams for illustrating the configuration of a cover that corresponds to the second cover. [Figure 15] 13 is a schematic side view illustrating a cover moving portion. FIG. [Figure 16] 11 is a schematic perspective view illustrating a cover moving portion. FIG. [Figure 17]1A and 1B are schematic plan views illustrating a jig used for window maintenance. [Figure 18] FIG. 1 is a schematic diagram illustrating the installation of windows. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment will be described with reference to the drawings. In the drawings, like elements are designated by like reference numerals and detailed description thereof will be omitted as appropriate. In each drawing, the arrows X, Y, and Z represent three directions that are perpendicular to each other. For example, the arrows X and Y represent the horizontal direction, and the arrow Z represents the vertical direction.

[0012] In the following, as an example, a dual frequency plasma processing apparatus having an inductively coupled electrode in the upper part and a capacitively coupled electrode in the lower part will be exemplified. However, the method of generating plasma is not limited to this. For example, the plasma processing apparatus may be a plasma processing apparatus using inductively coupled plasma (ICP) or a plasma processing apparatus using capacitively coupled plasma (CCP).

[0013] Furthermore, the present invention is not limited to a plasma processing apparatus that generates plasma using high frequency waves, but may be, for example, a plasma processing apparatus that generates plasma using microwaves. That is, the plasma processing apparatus 1 according to this embodiment may have a window that faces a stage on which an object to be processed is placed and that allows an electromagnetic field to pass through.

[0014] It should be noted that since known techniques can be applied to the general configuration of plasma processing apparatuses using inductively coupled plasma, capacitively coupled plasma, and microwave plasma, detailed descriptions of these plasma processing apparatuses will be omitted.

[0015] Moreover, the processing object 100 to be processed by the plasma processing apparatus 1 according to this embodiment may be, for example, a photomask, a mask blank, a wafer, a glass substrate, etc. However, the processing object 100 is not limited to the above-mentioned examples, and may be any object having a portion to be processed by radicals or ions generated by exciting and activating a gas G, which will be described later, with plasma.

[0016] 1 is a schematic cross-sectional view illustrating a plasma processing apparatus 1 according to the present embodiment. As shown in FIG. 1, the plasma processing apparatus 1 may be provided with a chamber 2, a power supply unit 3, a power supply unit 4, a pressure reducing unit 5, a gas supply unit 6, a mounting table 7, a detection unit 8, and a controller 9.

[0017] The controller 9 has, for example, a calculation unit such as a CPU (Central Processing Unit) and a storage unit such as a memory. The controller 9 can be, for example, a computer. The controller 9 controls the operation of each element provided in the plasma processing apparatus 1 based on a control program stored in the storage unit. Note that a known technique can be applied to the control program that controls the operation of each element, and therefore a detailed description thereof will be omitted.

[0018] The chamber 2 has an airtight structure capable of maintaining an atmosphere at a reduced pressure lower than atmospheric pressure. The chamber 2 has, for example, a substantially cylindrical shape. The chamber 2 can be made of, for example, a metal such as an aluminum alloy. The chamber 2 can be grounded.

[0019] A hole 2a for loading and unloading the processing object 100 can be provided in the side wall of the chamber 2. A load lock chamber 21 can be connected to the portion of the chamber 2 where the hole 2a is provided. A gate valve 22 can be provided in the load lock chamber 21. When performing plasma processing, the hole 2a is closed airtight by the gate valve 22. When loading and unloading the processing object, the hole 2a is connected to the load lock chamber 21 by the gate valve 22.

[0020] A window 23 is provided in the ceiling of the chamber 2 so as to be airtight. The window 23 faces the mounting table 7 (electrostatic chuck 71) on which the workpiece 100 is placed. The window 23 has a plate shape. An electromagnetic field can pass through the window 23. The window 23 can be made of a material that is not easily damaged during plasma processing. The window 23 can be made of a dielectric material such as quartz.

[0021] The power supply unit 3 generates plasma P in the internal space of the chamber 2. The power supply unit 3 is provided outside the chamber 2, on the opposite side of the window 23 from the mounting table 7. In the plasma processing apparatus 1, the power supply unit 3 serves as a plasma generating part capable of generating plasma P inside the chamber 2.

[0022] The power supply unit 3 includes, for example, an antenna 31, a matching box 32, and a power supply 33. The antenna 31 can be provided outside the chamber 2 and on the window 23. The antenna 31 is electrically connected to a power source 33 via a matching box 32. The antenna 31 can have, for example, a plurality of coils that generate an electromagnetic field and a plurality of capacitors. In addition, a cover 34 that covers the antenna 31 and the window 23 can be further provided. The cover 34 can be made of metal and can be grounded. In addition, a Faraday shield can be further provided between the antenna 31 and the window 23.

[0023] The matching device 32 may include a matching circuit for matching the impedance between the power source 33 side and the impedance on the plasma P side.

[0024] The power supply 33 may be a high-frequency power supply. The power supply 33 applies high-frequency power having a frequency of, for example, about 100 KHz to 100 MHz to the antenna 31. In this case, the power supply 33 applies high-frequency power having a frequency suitable for generating plasma P (for example, 13.56 MHz) to the antenna 31. The power supply 33 may also be configured to change the frequency of the high-frequency power it outputs.

[0025] The power supply unit 4 is provided for so-called bias control. That is, the power supply unit 4 is provided for controlling the energy of ions drawn into the treatment object 100. In this case, if the energy of ions drawn into the treatment object 100 is increased, the sputtering effect caused by ions is more likely to occur. On the other hand, if the energy of ions drawn into the treatment object 100 is decreased, chemical treatment by radicals is more likely to occur.

[0026] The power supply unit 4 includes, for example, a base 41, a matching box 42, and a power supply 43. The base 41 is provided on the bottom of the chamber 2 via an insulating member 41a. The insulating member 41a can cover the side surface of the base 41. The insulating member 41a can be made of a dielectric material such as quartz.

[0027] The base 41 is electrically connected to a power source 43 via a matching box 42. An electrostatic chuck 71 can be provided on the base 41. The base 41 serves as an electrode to which high-frequency power is applied from the power source 43, and also serves as a support base for supporting the electrostatic chuck 71. In this case, the base 41 has a flow path therein for flowing cooling water, and can also cool the electrostatic chuck 71. The base 41 can be made of a metal such as an aluminum alloy, for example.

[0028] The matching box 42 is electrically connected between the base 41 and the power source 43. The matching box 42 may include a matching circuit for matching the impedance between the power source 43 side and the impedance on the plasma P side.

[0029] The power supply 43 may be a high-frequency power supply. The power supply 43 applies to the base 41 high-frequency power having a frequency suitable for attracting ions (for example, a frequency of 1 MHz to 27 MHz).

[0030] The pressure reducing section 5 reduces the pressure inside the chamber 2 to a predetermined pressure. The pressure reducing unit 5 includes, for example, an opening / closing valve 51, a pump 52, and a pressure controller 53. The on-off valve 51 can be connected to, for example, a hole 2b provided in a side wall of the chamber 2. The on-off valve 51 opens and closes a flow path between the chamber 2 and the pump 52. The on-off valve 51 can be, for example, a poppet valve.

[0031] The pump 52 may be, for example, a turbo molecular pump (TMP).

[0032] The pressure controller 53 can be provided between the opening and closing valve 51 and the pump 52. The pressure controller 53 controls the internal pressure of the chamber 2 to a predetermined pressure based on the output of a vacuum gauge (not shown) or the like that detects the internal pressure of the chamber 2. The pressure controller 53 can be, for example, an APC (Auto Pressure Controller) or the like.

[0033] The gas supply unit 6 supplies the gas G to the internal space of the chamber 2 through the nozzles 2c provided on the side wall of the chamber 2. In this case, a plurality of the nozzles 2c can be provided at approximately equal intervals around the central axis of the chamber 2. In this way, it is possible to suppress the concentration of the gas G from varying in the region where the plasma P is generated.

[0034] The gas supply unit 6 includes, for example, a gas source 61, a gas controller 62, and an opening / closing valve 63. The gas source 61 supplies the gas G to the inside of the chamber 2 via a gas controller 62 and an opening / closing valve 63. The gas source 61 may be, for example, a high-pressure cylinder that stores the gas G. The gas source 61 may also be, for example, factory piping.

[0035] The gas G may be one that generates desired radicals or ions when excited and activated by the plasma P. For example, when the plasma processing is an etching process, the gas G may be one that generates radicals or ions that can etch the exposed surface of the processing object 100. In this case, the gas G may be, for example, a gas containing chlorine or a gas containing fluorine. For example, the gas G may be a mixed gas of chlorine gas and oxygen gas, CHF 3 , CHF 3 and CF 4 Mixture of gases, SF 6 and a mixture of helium gas.

[0036] The gas controller 62 can be provided between the gas source 61 and the chamber 2. The gas controller 62 controls at least one of the flow rate and pressure of the gas G supplied from the gas source 61. The gas controller 62 can be, for example, a mass flow controller (MFC).

[0037] The on-off valve 63 can be provided between the gas controller 62 and the chamber 2. The on-off valve 63 controls the start and stop of the supply of the gas G. The on-off valve 63 can be, for example, a two-port solenoid valve. The function of the on-off valve 63 can also be provided in the gas controller 62.

[0038] The mounting table 7 is provided inside the chamber 2, and the processing object 100 is placed thereon. The mounting table 7 includes, for example, an electrostatic chuck 71, a mask ring 72, a power supply unit 73, a temperature control unit 74, and lift pins 75.

[0039] The electrostatic chuck 71 generates an electrostatic force to adsorb the workpiece 100. The electrostatic chuck 71 may be one that uses Coulomb force or one that uses Johnsen-Rahbek force. The electrostatic chuck 71 can also control the temperature of the workpiece 100 during processing. That is, the electrostatic chuck 71 has at least the function of adsorbing the workpiece 100, and can also have the function of controlling the temperature of the workpiece 100.

[0040] The electrostatic chuck 71 can be provided on the base 41. The electrostatic chuck 71 can have, for example, a plate-shaped dielectric and an electrode provided inside the dielectric. The dielectric can be made of, for example, ceramics such as aluminum oxide.

[0041] A plurality of grooves can be provided on the surface of the dielectric. A temperature control gas is supplied to the plurality of grooves from a temperature control unit 74. The supplied temperature control gas flows through the space defined by the grooves and the placed workpiece 100, and heat is exchanged between the temperature control gas and the workpiece. The dielectric may have a plurality of holes penetrating the thickness direction. A lift pin 75 may be provided in each of the plurality of holes.

[0042] The electrode has a plate shape and can be made of a metal such as tungsten or molybdenum. The electrode can be either a monopolar or bipolar type. For example, in the case of a bipolar type, two electrodes can be provided side by side on the same plane.

[0043] The mask ring 72 has a cylindrical shape and can be provided, for example, near the periphery of the upper surface of the base 41 or near the periphery of the upper surface of the electrostatic chuck 71. The mask ring 72 can be made of a dielectric material such as quartz.

[0044] The power supply unit 73 includes, for example, a DC power supply 73a and a changeover switch 73b. The DC power supply 73a is electrically connected to an electrode of the electrostatic chuck 71. When a voltage is applied to the electrode by the DC power supply 73a, an electric charge is generated on the surface of the electrode facing the workpiece 100. Therefore, an electrostatic force is generated between the electrode and the workpiece 100, and the workpiece 100 is attracted to the electrostatic chuck 71 by the generated electrostatic force.

[0045] The changeover switch 73b is electrically connected between the DC power supply 73a and the electrode of the electrostatic chuck 71, and switches between attracting the workpiece 100 and releasing the attracting state.

[0046] The temperature control unit 74 supplies a temperature control gas to the electrostatic chuck 71 . The temperature control unit 74 includes, for example, a gas source 74a, a gas controller 74b, a temperature adjustment unit 74c, and an opening / closing valve 74d.

[0047] The gas source 74a may be, for example, a high-pressure cylinder containing a temperature control gas. The gas source 74a may be, for example, factory piping. The temperature control gas may be, for example, helium gas.

[0048] The gas controller 74b may be provided between the gas source 74a and the electrostatic chuck 71. The gas controller 74b controls, for example, the flow rate of the temperature control gas supplied from the gas source 74a. The gas controller 74b may be, for example, an MFC.

[0049] The temperature adjustment unit 74c can be provided between the gas controller 74b and the electrostatic chuck 71. The temperature adjustment unit 74c adjusts the temperature of the processing object 100 by adjusting the temperature of a temperature control gas. The temperature adjustment unit 74c can be, for example, at least one of a heating device such as a heater and a cooling device equipped with a heat exchanger or the like.

[0050] The opening and closing valve 74d can be provided between the temperature adjustment unit 74c and the electrostatic chuck 71. The opening and closing valve 74d controls the start and stop of the supply of the temperature control gas. The opening and closing valve 74d can be, for example, a two-port solenoid valve. The function of the opening and closing valve 74d can also be provided in the gas controller 74b.

[0051] A plurality of lift pins 75 may be provided. When transferring the processed object 100 to a transport device (not shown) or receiving the unprocessed object 100 from the transport device (not shown), the plurality of lift pins 75 are raised to protrude from the upper surface of the electrostatic chuck 71. When processing the object 100, the plurality of lift pins 75 are lowered to move the plurality of lift pins 75 below the upper surface of the electrostatic chuck 71. The plurality of lift pins 75 can be raised and lowered by, for example, a control motor such as a servo motor, an air cylinder, or the like.

[0052] Before describing the detector 8 according to the present embodiment, a detector 180 and a detector 280 according to comparative examples will be described. FIG. 2 is a schematic cross-sectional view illustrating a detection unit 180 according to a comparative example. FIG. 2 shows a case where a detection unit 180 and a transmission window 121 are provided instead of the detection unit 8 according to the present embodiment.

[0053] 2, the detection unit 180 according to the comparative example has a light projecting unit 180a and a light receiving unit 180b. The transmission windows 121 are provided on the side wall of the chamber 2 at positions facing the light projecting unit 180a and the side wall of the chamber 2 at positions facing the light receiving unit 180b.

[0054] The detection light emitted from the light-projecting unit 180a passes through the transmission window 121 and enters a detection position on the surface of the object 100 to be processed. The detection light is irradiated onto the surface of the object 100 to be processed at an angle θa between the surface of the object 100 and the detection light. The detection light that enters the detection position is reflected, passes through the transmission window 121, and enters the light-receiving unit 180b. The light-receiving unit 180b converts the reflected light that enters into an electrical signal according to the amount of received light. The controller 9 detects the state of the object 100 to be processed based on the electrical signal.

[0055] Here, it is assumed that the detection light is irradiated perpendicularly to a detection position on the surface of the processing object 100. The detection light is emitted from the light projecting unit 180a and spreads before reaching the surface of the processing object 100. In general, the irradiation area of ​​the detection light at the detection position is determined in advance based on the diameter of the aperture of the light projecting unit 180a and the spread of the detection light. In this case, if the irradiation area of ​​the detection light at the detection position becomes large, information around the detection position is likely to be mixed into the detection result. Therefore, it is preferable to make the irradiation area of ​​the detection light at the detection position as small as possible. The spread of the detection light is proportional to the distance L1 shown in FIG. 3.

[0056] However, as shown in Fig. 2, when a light projecting unit 180a is provided on the side of the chamber 2 and the detection light is irradiated onto the surface of the object 100 from a direction inclined with respect to the surface of the object 100, the irradiation area of ​​the detection light at the detection position becomes larger than the above-mentioned predetermined irradiation area. For example, in Fig. 2, the irradiation area of ​​the detection light at the detection position spreads in the X direction. Therefore, information about the surroundings of the detection position is mixed into the detection result, making it difficult to detect a slight change at the detection position.

[0057] Furthermore, when the distance L between the mounting table 7 on which the workpiece 100 is placed and the window 23 provided above the mounting table 7 becomes longer, the radicals generated by the plasma P generated directly below the window 23 tend to be deactivated before reaching the workpiece 100 placed on the mounting table 7. Therefore, the distance L between the mounting table 7 and the window 23 tends to become shorter. When the distance L between the mounting table 7 and the window 23 becomes shorter, the angle θa between the surface of the workpiece 100 and the detection light becomes smaller. The smaller the angle θa, the larger the spread of the irradiation area in the X direction becomes. Therefore, the irradiation area of ​​the detection light at the detection position becomes even larger.

[0058] Furthermore, in recent years, the processed parts have become finer, and for example, the opening ratio of the formed irregularities, holes, etc. may be 1% or less. In such cases, the amount of material removed is reduced, so the change in the detection light becomes even more minute, making it more difficult to detect the optical change at the detection position. In this way, when the detection unit 180 is provided on the side of the chamber 2, it becomes difficult to detect optical changes at the detection position with good accuracy.

[0059] As described above, the nozzle 2c for supplying the gas G into the chamber 2 and the load lock chamber 21 are provided on the side wall of the chamber 2, so that the installation position of the window 23 is limited. In addition, since the chamber 2 needs to have an airtight structure, it is difficult to provide a large window 23. If the installation position of the window 23 is limited or if a large window 23 is not provided, the arrangement of the light projecting unit 180a and the light receiving unit 180b is limited. If the arrangement of the light projecting unit 180a and the light receiving unit 180b is limited, the detection position is limited, making it difficult to change the detection position.

[0060] As described above, if the detection unit 180 is provided on the side of the chamber 2, it becomes difficult to improve the detection accuracy and change the detection position.

[0061] FIG. 3 is a schematic cross-sectional view illustrating a detection unit 280 according to another comparative example. FIG. 3 shows a case where a detector 280 is provided in place of the detector 8 according to the present embodiment. As shown in Fig. 3, the detection unit 280 can be a so-called light-emitting and receiving sensor in which a light-emitting unit and a light-receiving unit are integrated. The detection unit 280 is provided outside the chamber 2, on the opposite side of the window 23 from the mounting table 7 side. The detection unit 280 makes detection light incident on the detection position from a direction approximately perpendicular to the surface of the workpiece 100, and receives the reflected light reflected at the detection position. In this way, the irradiation area of ​​the detection light at the detection position becomes approximately the same as the above-mentioned predetermined irradiation area. Therefore, it becomes easy to detect a change at the detection position with high accuracy.

[0062] However, as described above, the antenna 31, the Faraday shield, and the like are provided above the window 23. Therefore, the arrangement of the detection unit 280 is limited by the antenna 31, the Faraday shield, and the like. Therefore, if the detection unit 280 is provided above the window 23, even if the detection accuracy is improved, it becomes difficult to change the detection position.

[0063] Returning to FIG. 1, the detection unit 8 according to this embodiment will now be described. The detector 8 detects the state of the treatment object 100 based on an optical change that occurs during the plasma treatment. For example, the detector 8 can be used to detect the end point of the plasma treatment.

[0064] As shown in FIG. 1, the detection unit 8 includes, for example, a light projecting unit 81 and a light receiving unit . The light-projecting unit 81 may be, for example, a light-emitting diode or a laser diode. The light-projecting unit 81 may irradiate detection light onto the surface of the object 100 to be processed through the window 23. The light-projecting unit 81 may be provided facing an inclined surface 23a1 to be described later.

[0065] The light receiving unit 82 can receive reflected light that is reflected on the surface of the processing object 100 and exits through the window 23. For example, the light receiving unit 82 can receive interference light generated when the detection light is incident on the detection position of the processing object 100 and convert it into an electrical signal. The light receiving unit 82 can be, for example, a photodiode. Note that the light receiving unit 82 is not limited to a photodiode, and can be anything that can detect optical changes. The light receiving unit 82 can be provided facing the inclined surface 23a2 described below.

[0066] The light receiving unit 82 may further include a spectroscope. If a spectroscope is provided, light having a predetermined wavelength can be extracted, thereby improving the detection accuracy. The controller 9 can detect the state of the processing object (for example, the end point of the plasma processing) based on the signal from the light receiving unit 82.

[0067] 1, a portion of the periphery of the window 23 is provided with an inclined surface 23a1 (corresponding to an example of a first inclined surface) and an inclined surface 23a2 (corresponding to an example of a second inclined surface). If the inclined surfaces 23a1 and 23a2 are uneven, the unevenness will cause light to be scattered, so it is preferable to increase the flatness of the inclined surfaces 23a1 and 23a2. For example, the surface roughness of the inclined surfaces 23a1 and 23a2 can be reduced to Ra 0.02 or less by optical polishing.

[0068] FIG. 4 is a schematic cross-sectional view illustrating light projecting portion 81, light receiving portion 82, inclined surface 23a1, and inclined surface 23a2. FIG. 5 is a schematic plan view illustrating the light projecting portion 81, the light receiving portion 82, the inclined surface 23a1, and the inclined surface 23a2.

[0069] 4 and 5, for example, one end of the inclined surface 23a1 can be connected to the surface of the window 23 opposite to the mounting table 7 side. For example, the other end of the inclined surface 23a1 can be connected to a side surface of the window 23. For example, one end of the inclined surface 23a2 can be connected to the surface of the window 23 opposite to the mounting table 7 side. For example, the other end of the inclined surface 23a2 can be connected to a side surface of the window 23.

[0070] As shown in FIG. 5, in a plan view, the inclined surface 23a2 can be provided at a position facing the inclined surface 23a1 across the central axis 23b of the window 23. 4, inclined surface 23a1 is inclined with respect to central axis 23b of window 23. Inclined surface 23a2 is inclined with respect to central axis 23b of window 23. The inclination direction of inclined surface 23a2 is opposite to the inclination direction of inclined surface 23a1.

[0071] For example, when window 23 is made of quartz and the internal pressure of chamber 2 is about 0.1 Pa to 100 Pa, angle θ1 between inclined surface 23a1 and the surface of window 23 opposite to the mounting table 7 side can be set to "θ1≦43°," as shown in Fig. 4. In this way, it is possible to prevent the detection light emitted from light-projecting unit 81 and introduced into window 23 via inclined surface 23a1 from being totally reflected by the surface of window 23 facing the mounting table 7.

[0072] The angle θ2 between the inclined surface 23a2 and the surface of the window 23 opposite to the mounting table 7 side can be set to "θ2≦43°." In this way, it is possible to prevent the reflected light that is reflected at the detection position of the workpiece 100 and enters the surface of the window 23 facing the mounting table 7 from being totally reflected by the surface of the window 23 facing the mounting table 7.

[0073] Furthermore, the angle θ2 can be set to be the same as the angle θ1. However, when the angles θ1 and θ2 are set to be the same, a difference on the order of a manufacturing error can be tolerated. In other words, the angle θ2 can be set to be approximately the same as the angle θ1.

[0074] There are no particular limitations on the planar dimension L2 of inclined surface 23a1 and the planar dimension L3 of inclined surface 23a2 shown in Fig. 5. For example, as shown in Fig. 5, planar dimension L2 of inclined surface 23a1 can be equal to or larger than planar dimension L4 of light-projecting portion 81. For example, planar dimension L3 of inclined surface 23a2 can be equal to or larger than planar dimension L5 of light-receiving portion 82. In this case, planar dimension L3 of inclined surface 23a2 may be the same as or different from planar dimension L2 of inclined surface 23a1.

[0075] A gap may be provided between the light-projecting end of light-projecting unit 81 and inclined surface 23a1, or, as shown in FIG. 4, the light-projecting end of light-projecting unit 81 may be brought into contact with inclined surface 23a1. However, if a gap is provided between the end of the light-projecting unit 81 on the light-projecting side and the inclined surface 23a1, when vibration is applied to the plasma processing apparatus 1, the light-projecting unit 81 and the inclined surface 23a1 will vibrate separately, which may cause noise. In addition, noise may be generated when external light is incident on the inclined surface 23a1 through the gap. Therefore, it is preferable to bring the end of the light-projecting unit 81 on the light-projecting side into contact with the inclined surface 23a1. Note that a light guide having an optical fiber or the like may be provided between the end of the light-projecting unit 81 on the light-projecting side and the inclined surface 23a1. If a light guide is provided, it becomes easy to arrange the light-projecting unit 81 at any position.

[0076] A gap may be provided between the light-receiving end of the light-receiving portion 82 and the inclined surface 23a2, or the light-receiving end of the light-receiving portion 82 may be in contact with the inclined surface 23a2, as shown in FIG. 4. However, if a gap is provided between the end of the light receiving side of the light receiving unit 82 and the inclined surface 23a2, when vibration is applied to the plasma processing apparatus 1, the light receiving unit 82 and the inclined surface 23a2 will vibrate separately, which may cause noise. In addition, noise may be generated when external light is incident on the light receiving unit 82 through the gap. Therefore, it is preferable to bring the end of the light receiving side of the light receiving unit 82 into contact with the inclined surface 23a2. Note that a light guide having an optical fiber or the like may be provided between the end of the light receiving side of the light receiving unit 82 and the inclined surface 23a2. If a light guide is provided, it becomes easy to arrange the light receiving unit 82 at any position.

[0077] The window 23 does not have an antenna 31, a Faraday shield, or the like provided on its periphery. Therefore, the inclined surface 23a1 and the inclined surface 23a2 can be provided at any position, making it easy to detect a desired position on the surface of the object 100 to be treated. As described above, the smaller the angle θa, the larger the irradiation area. By irradiating the detection light from the inclined surface 23a1 of the window 23, the angle θa can be made larger than that of the detection unit 180. Therefore, the irradiation area can be made smaller than that of the detection unit 180.

[0078] In addition, although the example has been described in which one set of inclined surface 23a1 and inclined surface 23a2 is provided, multiple sets of inclined surface 23a1 and inclined surface 23a2 may be provided. If multiple sets of inclined surface 23a1 and inclined surface 23a2 are provided, inclined surface 23a1 and inclined surface 23a2 can be selected according to a desired detection position.

[0079] Next, the change of the detection position will be described. If a plurality of pairs of inclined surfaces 23a1 and 23a2 are provided, the detection position can be changed by selecting inclined surface 23a1 and inclined surface 23a2. The detection position can also be changed when a pair of inclined surfaces 23a1 and 23a2 is provided. In the following, a case where a pair of inclined surfaces 23a1 and 23a2 is provided will be described.

[0080] FIG. 6 is a schematic cross-sectional view for illustrating the change of the detection position. 6, by moving light-projecting unit 81 along the inclination direction of inclined surface 23a1, it is possible to change the incident position (detection position) of the detection light on the surface of object 100. If the incident position of the detection light changes, the incident position of the reflected light on inclined surface 23a2 changes, and therefore light-receiving unit 82 is moved according to the incident position of the reflected light on inclined surface 23a2. In this way, it is possible to easily change the detection position on the surface of the processing object 100. Therefore, it is possible to detect the processing state at a plurality of points on the surface of the processing object 100.

[0081] In the example shown in Fig. 6, light-projecting unit 81 is moved along the inclination direction of inclined surface 23a1, but light-projecting unit 81 may be moved in the Y direction along inclined surface 23a1 as shown in Fig. 5. Also, light-projecting unit 81 may be moved in the inclination direction of inclined surface 23a1 and in the Y direction. That is, if light projecting portion 81 is provided so as to be movable along inclined surface 23a1 and light receiving portion 82 is provided so as to be movable along inclined surface 23a2, the detection position can be changed.

[0082] Furthermore, when a plurality of pairs of inclined surfaces 23a1 and 23a2 are provided, the selection of an inclined surface can be combined with the movement of light projecting unit 81 and light receiving unit 82 along the inclined surface.

[0083] The light projecting unit 81 and the light receiving unit 82 can be moved, for example, by an operator changing the mounting positions of the light projecting unit 81 and the light receiving unit 82. As shown in FIG. 1, a moving unit 81a (corresponding to an example of a first moving unit) for moving the light projecting unit 81 and a moving unit 82a (corresponding to an example of a second moving unit) for moving the light receiving unit 82 can be further provided. The moving units 81a and 82a can be, for example, a single-axis table capable of single-axis control or a two-axis table capable of two-axis control. In addition, a combination of a plurality of single-axis tables or a combination of a single-axis table and a two-axis table can also be used. If the moving units 81a and 82a are provided, it becomes possible to sequentially change the detection position by the controller 9. Therefore, it becomes possible to detect the processing state of a plurality of points on the surface of the processing object 100 in real time.

[0084] 1, a cover 83 for covering the light-projecting unit 81 and the light-receiving unit 82 may be further provided. The cover 83 is made of metal and may be grounded. When the light-projecting unit 81 and the light-receiving unit 82 are arranged, a hole may be provided in the cover 34 described above. If a hole is provided in the cover 34, the electromagnetic field generated in the antenna 31 may leak to the outside of the plasma processing apparatus 1. If the cover 83 is provided, the electromagnetic field leaking from the cover 34 can be prevented from leaking to the outside of the plasma processing apparatus 1. The cover 34 may cover the antenna 31, the light-projecting unit 81, the light-receiving unit 82, and the moving units 81a and 82a.

[0085] Next, an example of a specific configuration of the moving sections 81a and 82a will be described. FIG. 7 is a schematic diagram illustrating the moving units 181 and 182. As shown in FIG. The moving unit 181 is an example of a specific configuration of the moving unit 81 a that moves the light projecting unit 81 . The moving section 182 is an example of a specific configuration of the moving section 82a that moves the light receiving section 82. 7, a light projecting unit 81 can be attached to moving unit 181. A light receiving unit 82 can be attached to moving unit 182. Moving unit 181 is provided at a position facing moving unit 182 with window 23 in between. The configuration of moving section 181 can be similar to the configuration of moving section 182. Therefore, hereinafter, the configuration of moving section 182 will be mainly described.

[0086] FIG. 8 is a schematic diagram of the moving portion 182 in FIG. 7 as viewed from the X direction. As shown in FIGS. 7 and 8, the moving portion 182 (181) has a guide 182a (181a), a guide 182b (181b), and a case 182c (181c). The guide 182a (181a) is provided on the outer surface of the cover .

[0087] FIG. 9 is a schematic diagram illustrating the guide 182a (181a). FIG. 10 is a schematic diagram illustrating the guide 182b (181b). FIG. 11 is a schematic diagram of the guide 182b (181b) in FIG. 10 as viewed from the Z direction.

[0088] As shown in FIGS. 8 and 9, the guide 182a (181a) has a pair of rails 182a1 (181a1) and a base 182a2 (181a2). The pair of rails 182a1 (181a1) are provided around a hole 34a provided in the cover 34. The pair of rails 182a1 (181a1) face each other across the hole 34a. For example, the pair of rails 182a1 (181a1) extend along the long sides of the rectangular hole 34a.

[0089] The pedestal 182a2 (181a2) is provided on a pair of rails 182a1 (181a1). The pedestal 182a2 (181a2) is provided movably along the pair of rails 182a1 (181a1). A rectangular hole 182a3 (181a3) is provided on the surface of the pedestal 182a2 (181a2) facing the cover 34. In addition, a holding device (not shown) for holding the position of the pedestal 182a2 (181a2) may be provided.

[0090] The guide 182a (181a) is not limited to the illustrated configuration, and may be any guide mechanism capable of linear movement. For example, the guide 182a (181a) may be a guide mechanism having a linear bearing.

[0091] As shown in FIGS. 8, 10, and 11, the guide 182b (181b) is provided on a base 182a2 (181a2). The guide 182b (181b) has a pair of rails 182b1 (181b1) and a base 182b2 (181b2). The pair of rails 182b1 (181b1) are provided around the hole 182a3 (181a3) provided in the base 182a2 (181a2). The pair of rails 182b1 (181b1) face each other with the hole 182a3 (181a3) in between. For example, the pair of rails 182b1 (181b1) extend along the long sides of the rectangular hole 182a3 (181a3).

[0092] The base 182b2 (181b2) is provided on a pair of rails 182b1 (181b1). The base 182b2 (181b2) is provided so as to be movable along the pair of rails 182b1 (181b1). A hole 182b4 (181b4) into which the case 182c (181c) is inserted is provided on the surface of the base 182b2 (181b2) facing the cover 34. A screw hole 182b5 (181b5) into which the enamel set (set screw) 182b3 (181b3) is screwed is provided on the opposite side surface of the base 182b2 (181b2). A holding device (not shown) for holding the position of the base 182b2 (181b2) may be provided.

[0093] The guide 182b (181b) is not limited to the illustrated configuration, and may be any guide mechanism capable of linear movement. For example, the guide 182b (181b) may be a guide mechanism having a linear bearing.

[0094] As shown in FIG. 7, a light projecting unit 81 is provided inside case 181c, and a light receiving unit 82 is provided inside case 182c. 12(a) to (c) are schematic views illustrating the case 182c (181c). As shown in Fig. 12(a), the case 182c (181c) may be a box having a substantially rectangular parallelepiped shape. On the opposing side surfaces in the short side direction of the case 182c (181c), a recessed groove 182c1 (181c1) is provided extending in the longitudinal direction of the case 182c (181c). On one side surface in the longitudinal direction of the case 182c (181c), the light receiving surface (light projecting surface) of the light receiving unit 82 (light projecting unit 81) is exposed, and wiring is drawn out from the other side surface.

[0095] A screw hole (not shown) is provided on the side of the case 182c (181c) where the recessed groove 182c1 (181c1) is not provided. A groove (not shown) is also provided on the side of the light receiving unit 82 (light projecting unit 81). An enamel set (set screw) is screwed into the screw hole provided on the side of the case 182c (181c), and the enamel set (set screw) is inserted into the groove provided on the side of the light receiving unit 82 (light projecting unit 81). The light receiving unit 82 (light projecting unit 81) is fixed to the case 182c (181c) by being pressed by the inserted enamel set.

[0096] The method of fixing the light receiving unit 82 (light projecting unit 81) to the case 182c (181c) is not limited to the above. For example, a plurality of recesses are provided on the side surface of the light receiving unit 82 (light projecting unit 81), and a hole is provided on the side surface of the case 182c (181c) where the recessed groove 182c1 (181c1) is not provided. Then, a pin may be inserted into one of the plurality of recesses provided in the light receiving unit 82 (light projecting unit 81) through the hole provided on the side surface of the case 182c (181c), thereby fixing the light receiving unit 82 (light projecting unit 81) to the case 182c (181c). In addition, the outer periphery of the light receiving unit 82 (light projecting unit 81) is male-threaded, and a hole penetrating the case 182c (181c) in the longitudinal direction is female-threaded. The light receiving unit 82 (light projecting unit 81) may be fixed to the case 182c (181c) by screwing the light receiving unit 82 (light projecting unit 81) into the case 182c (181c).

[0097] 12(b) and (c), the case 182c (181c) is inserted into the hole 182b4 (181b4) of the base 182b2 (181b2). The enamel set (set screw) 182b3 (181b3) is screwed into the screw hole 182b5 (181b5) of the base 182b2 (181b2). The enamel set (set screw) 182b3 (181b3) protrudes into the hole 182b4 (181b4) and is inserted into the dug groove 182c1 (181c1) of the case 182c (181c). Therefore, it is possible to adjust the position of the case 182c (181c) relative to the base 182b2 (181b2), and therefore the position of the light receiving unit 82 (light projecting unit 81) relative to the inclined surface 23a2 of the window 23. In addition, the case 182c (181c) is connected to the cover 34 via the base 182b2 (181b2). Therefore, the light receiving unit 82 (light projecting unit 81) can be connected to the cover 34. It is also possible to provide a holding device (not shown) for holding the position of the case 182c (181c).

[0098] The method of connecting the base 182b2 (181b2) and the case 182c (181c) is not limited to the illustrated configuration. For example, a plurality of recesses may be provided on the side surface of the case 182c (181c) instead of the groove 182c1 (181c1), and a hole may be provided instead of the screw hole 182b5 (181b5) of the base 182b2 (181b2). Then, a pin may be inserted into one of the recesses provided in the case 182c (181c) through the hole provided in the base 182b2 (181b2), thereby connecting the base 182b2 (181b2) and the case 182c (181c). The case 182c (181c) may also be clamped and fixed in a vice. In this case, the clamping portion of the vice is inserted into the hole of the base 182b2 (181b2) and protrudes into the hole 182b4 (181b4).

[0099] When a plurality of light projecting units 81 (light receiving units 82) are provided, a plurality of moving units 181 (182) can be provided. FIG. 13 is a schematic diagram for illustrating a plurality of moving parts. As shown in FIG. 13, when a plurality of moving parts 181 (182) are provided, a guide 182a (181a) may be used for both. In this way, the structure of the moving part can be simplified.

[0100] 14 is a schematic diagram illustrating the configuration of the cover 83, which corresponds to the second cover. As described above, the cover 83 can be provided on the cover 34. The cover 83 is made up of a main body 83b and a door 83a. The main body 83b is, for example, a metal tube. One end of the main body 83b is connected to the cover 34. If the hole 34a of the cover 34 can be sealed between the cover 83 and the ceiling of the chamber 2, the surface of the main body 83b that contacts the chamber 2 can be omitted. In other words, the main body 83b may be a metal plate having an n-shaped cross section. The door 83a is, for example, a metal plate. The door 83a is provided at the other end of the main body 83b so as to be openable and closable. For example, the door 83a is connected to the other end of the main body 83b via a hinge. 14, when the door 83a is closed, the door 83a forms the outer surface of the cover 83. In addition, the door 83a may be provided with a stopper (not shown) for maintaining the door 83a in an open state.

[0101] 1, the cover 83 covers the light projecting unit 81, the light receiving unit 82, and the moving units 81a, 82a (181, 182). Furthermore, the light projecting unit 81, the light receiving unit 82, and the moving units 81a, 82a (181, 182) may require maintenance or adjustment by an operator. If the cover 83 is provided with the door 83a, maintenance and adjustment can be easily performed by an operator.

[0102] As described above, the cover 83 can suppress the electromagnetic field leaking from the cover 34 from leaking to the outside of the plasma processing apparatus 1. The cover 83 can also prevent disturbance light from entering the light-projecting unit 81 and the light-receiving unit 82.

[0103] Next, maintenance of the plasma processing apparatus 1 according to this embodiment will be described. As shown in FIG. 1, a window 23, a power supply unit 3, and a detection unit 8 are provided on the ceiling side of the chamber 2. These elements require maintenance. For example, the window 23 is damaged over time as a result of performing plasma processing. This requires replacement or repair of the window 23. Also, parts of the power supply unit 3 and the detection unit 8 may need to be replaced or adjusted.

[0104] However, the window 23, the power supply unit 3, and the detector 8 are covered with a cover 34 for blocking the electromagnetic field generated by the antenna 31. Therefore, it is necessary to remove the cover 34 when performing maintenance and to reinstall the cover 34 after the maintenance. As described above, the cover 34 is provided with a moving section to which the light projecting section 81 is attached and a moving section to which the light receiving section 82 is attached. Therefore, when reinstalling the cover 34, it is necessary to place the cover 34 in the original position.

[0105] Therefore, the plasma processing apparatus 1 according to the present embodiment is provided with a cover moving unit 10 capable of moving the cover 34 up and down. FIG. 15 is a schematic side view illustrating the cover moving part 10. As shown in FIG. FIG. 16 is a schematic perspective view for illustrating the cover moving part 10. As shown in FIG. As shown in FIGS. 15 and 16, the cover moving section 10 has, for example, a holding section 11, a driving section 12, and a plurality of positioning pins 13.

[0106] The holding portion 11 holds the cover 34 . The drive unit 12 raises and lowers the holder 11. When the holder 11 is raised by the drive unit 12, the cover 34 held by the holder 11 moves above the chamber 2. This allows the window 23 and the power supply unit 3 provided on the ceiling side of the chamber 2 to be exposed, facilitating maintenance of the window 23 and the power supply unit 3. 16, the driving unit 12 can also rotate the holding unit 11. For example, the driving unit 12 can rotate the holding unit 11 when raising the holding unit 11 or at the raised end. In this way, the cover 34 can be moved to the side of the chamber 2, making maintenance of the window 23 and the power supply unit 3 even easier. Furthermore, since the light-projecting unit 81 and the light-receiving unit 82 can be moved together with the cover 34, maintenance is made even easier. The work of removing the light-projecting unit 81 and the light-receiving unit 82 can be omitted. Furthermore, the light-projecting unit 81 and the light-receiving unit 82 are fixed to the cover 34. Therefore, when the cover 34 is returned to its original position for reinstallation, the light-projecting unit 81 and the light-receiving unit 82 also return to their original positions. Therefore, readjustment of the optical axes of the light-projecting unit 81 and the light-receiving unit 82 can also be made easy.

[0107] 16, a plurality of positioning pins 13 can be provided on the ceiling of the chamber 2. Furthermore, holes into which the positioning pins 13 are inserted can be provided in the holder 11 or the cover 34. When the holder 11 is lowered by the drive unit 12, the positioning pins 13 are inserted into the holes provided in the holder 11 or the cover 34. Therefore, the cover 34 can be placed in its original position.

[0108] 17(a) and (b) are schematic plan views illustrating a jig 123 used for the maintenance of the window 23. FIG. FIG. 17(b) is a schematic enlarged view of part A of the jig 123 in FIG. 17(a). FIG. 18 is a schematic diagram illustrating the installation of the window 23. As shown in Figures 17(a) and 18, the jig 123 has a substantially circular ring shape. The jig 123 has a plurality of holes 123b for inserting the positioning pins 13. It is preferable that the positioning pins 13 are arranged asymmetrically with respect to the circular jig 123 so that the jig 123 is always arranged at a predetermined position and in a predetermined orientation every time maintenance is performed. In this way, the positioning pins 13 are arranged so that they will not fit into the holes 123b in any other orientation than the predetermined position. 17(a) and (b), a protrusion 123a is provided on the inner wall of the jig 123. The tip of the protrusion 123a is capable of contacting a flat surface 23a3 provided on the periphery of the window 23. That is, the periphery of the window 23 is provided with a flat surface 23a3 that comes into contact with the protrusion 123a provided on the inner wall of the approximately annular jig 123.

[0109] 18, when installing the window 23, first, the jig 123 is installed on the ceiling of the chamber 2. At this time, the positioning pin 13 is inserted into the hole 123b, so that the jig 123 is installed at a predetermined position in a predetermined orientation. Next, the window 23 is inserted into the jig 123, and the flat surface 23a3 of the window 23 is brought into contact with the protrusion 123a of the jig 123. In this manner, the position of the window 23 relative to the chamber 2 can be determined. Next, after the window 23 is fixed to the chamber 2 , the jig 123 is removed from the chamber 2 . Using the jig 123 makes it easier to place the window 23 in place.

[0110] Although the embodiments have been described above, the present invention is not limited to these descriptions. With respect to the above-described embodiments, those skilled in the art may add or remove components or modify the design, or add or omit steps or change conditions, as appropriate, and these are also included within the scope of the present invention as long as they incorporate the characteristics of the present invention. Furthermore, the elements of each of the above-described embodiments can be combined to the greatest extent possible, and combinations of these are also included within the scope of the present invention as long as they include the features of the present invention.

[0111] For example, an elastic body may be provided on one side surface in the longitudinal direction of the case 182c (181c). One side surface in the longitudinal direction of the case 182c (181c) is a surface that comes into contact with the window 23. Therefore, it is preferable that the elastic body is made of a material having a lower hardness than the window 23. The elastic body may be, for example, rubber or sponge. By providing the elastic body, it is possible to prevent the window 23 from being damaged when the cover moving unit 10 returns the cover 34 to its original position. Note that, in the case where the elastic body does not prevent light from passing through the light receiving surface (light projecting surface) of the light receiving unit 82 (light projecting unit 81), the elastic body may also be provided on the light receiving surface (light projecting surface) of the light receiving unit 82 (light projecting unit 81).

[0112] For example, the case 182c (181c) may be moved to a position away from the window 23 as shown in FIG. 12(b) before the cover 34 is returned to its original position. In this way, the window 23 can be prevented from being damaged when the cover moving unit 10 returns the cover 34 to its original position. Compared to the case where the elastic body is provided, the optical axes of the light projecting unit 81 and the light receiving unit 82 need to be readjusted. Therefore, the amount of work by the worker increases. Therefore, the time required for maintenance increases. However, if the base 182b2 (181b2) is held on the pair of rails 182b1 (181b1), the position of the case 182c (181c) in the Y direction is the same as the original position. Therefore, compared to the case where the light projecting unit 81 and the light receiving unit 82 are separate from the cover 34, it is easy to readjust the optical axes of the light projecting unit 81 and the light receiving unit 82. Therefore, the amount of work by the worker decreases. As a result, the time required for maintenance decreases. [Explanation of symbols]

[0113] 1 plasma processing apparatus, 2 chamber, 3 power supply unit, 4 power supply unit, 5 pressure reducing section, 6 gas supply section, 7 mounting table, 8 detection section, 9 controller, 10 cover moving section, 23 window, 23a1 inclined surface, 23a2 inclined surface, 23a3 flat surface, 23b central axis, 31 antenna, 34 cover, 81 light projecting section, 81a moving section, 82 light receiving section, 82a moving section, 100 processing object, 123 jig, 123a convex section, G gas

Claims

1. A chamber capable of maintaining an atmosphere reduced in pressure below atmospheric pressure; a gas supply unit capable of supplying a gas into the chamber; a stage provided inside the chamber and capable of supporting an object to be treated; a pressure reducing unit capable of reducing the pressure inside the chamber; a window provided in the chamber and facing the stage; a plasma generating unit that is provided outside the chamber, on a side opposite to the side of the window from the mounting table, and that is capable of generating plasma inside the chamber; a light projection unit capable of irradiating light onto a surface of the workpiece through the window; a light receiving unit capable of receiving reflected light that is reflected by a surface of the object to be processed and exits through the window; Equipped with The periphery of the window is a first inclined surface inclined with respect to a central axis of the window; a second inclined surface inclined relative to a central axis of the window and having an inclination direction opposite to that of the first inclined surface; is established, The light projecting unit faces the first inclined surface, The light receiving unit faces the second inclined surface.

2. 2 . The plasma processing apparatus according to claim 1 , wherein, in a plan view, the second inclined surface faces the first inclined surface across a central axis of the window.

3. 3. The plasma processing apparatus according to claim 1, wherein the following formula is satisfied, where θ1 is an angle between the first inclined surface and a surface of the window opposite to the mounting table side: θ1=θ2 / θ3. θ1≦43°

4. 4. The plasma processing apparatus according to claim 1, wherein the following formula is satisfied, when an angle between the second inclined surface and a surface of the window opposite to the mounting table side is θ2: θ2≦43°

5. an angle between the first inclined surface and a surface of the window opposite to the mounting table side is θ1; 5. The plasma processing apparatus according to claim 1, wherein when the angle between the second inclined surface and the surface of the window opposite the mounting table side is θ2, the angle θ2 is approximately the same as the angle θ1.

6. the light projecting unit is provided to be movable along the first inclined surface, 6. The plasma processing apparatus according to claim 1, wherein the light receiving section is provided so as to be movable along the second inclined surface.

7. A first moving unit capable of moving the light projecting unit; A second moving unit capable of moving the light receiving unit; The plasma processing apparatus according to claim 6, further comprising:

8. a cover that covers an antenna provided in the plasma generating unit and the window; A cover moving unit capable of raising and lowering the cover; 8. The plasma processing apparatus according to claim 1, further comprising:

9. The plasma generating device further includes a cover for covering an antenna provided in the plasma generating unit and the window, The plasma processing apparatus according to claim 7 , wherein the first moving part and the second moving part are attached to the cover.

10. 10. The plasma processing apparatus according to claim 1, wherein a flat surface is provided on the periphery of the window, the flat surface being in contact with a protrusion provided on an inner wall of a substantially annular jig.

11. A second cover that covers the light-emitting unit and the light-receiving unit, 11. The plasma processing apparatus according to claim 1, wherein an outer surface of the second cover is openable and closable.

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