Plasma processing device

Abstract

The present invention provides a plasma processing apparatus capable of adjusting the supply amount of ions generated by plasma. It comprises: a processing chamber; a rotating stage disposed within the processing chamber and capable of circumferentially mounting a substrate; a processing gas supply nozzle capable of supplying processing gas to the rotating stage; a plasma antenna located on the processing chamber, covering at least a portion of the processing gas supply nozzle; and an ion trapping plate disposed above the processing gas supply nozzle, within the processing chamber, at least partially overlapping the plasma antenna.

Description

Technical Field

[0001] This invention relates to plasma processing apparatus. Background Technology

[0002] Conventionally, a plasma processing apparatus with an antenna device is known, which includes: a plurality of antenna members extending along a predetermined rotational shape having a long side direction and a short side direction, and having their ends connected to each other in pairs with their connection positions in the long side direction facing each other in the short side direction; a connecting member that connects the ends of adjacent plurality of antenna members to each other, is deformable and conductive; and at least two up-and-down movement mechanisms that are individually connected to at least two of the plurality of antenna members, enabling at least two of the plurality of antenna members to move up and down to change the bending angle with the connecting member as a fulcrum (for example, see Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-41685 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] This disclosure provides a plasma processing apparatus capable of adjusting the supply of ions generated by plasma.

[0008] Solution for solving the problem

[0009] To achieve the above objectives, a plasma processing apparatus according to a technical solution of the present invention comprises:

[0010] Processing room;

[0011] A rotating stage, located within the processing chamber, is capable of circumferentially placing a substrate.

[0012] A processing gas supply nozzle is provided, which is capable of supplying processing gas to the rotary table;

[0013] A plasma antenna, positioned on the processing chamber at least partially covering the processing gas supply nozzle; and

[0014] An ion trapping plate is positioned above the processing gas supply nozzle within the processing chamber, at least partially overlapping with the plasma antenna.

[0015] The effects of the invention

[0016] According to this disclosure, the supply of ions generated by the plasma antenna can be adjusted. Attached Figure Description

[0017] Figure 1 This is a schematic longitudinal sectional view of an example of a plasma processing apparatus according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic top view of an example of a plasma processing apparatus according to an embodiment of the present invention.

[0019] Figure 3 This is a cross-sectional view of the plasma processing apparatus according to an embodiment of the present invention along the concentric circles of the base.

[0020] Figure 4 This is a longitudinal sectional view of an example of the plasma generation section of a plasma processing apparatus according to an embodiment of the present invention.

[0021] Figure 5 This is an exploded perspective view of an example of the plasma generation unit of a plasma processing apparatus according to an embodiment of the present invention.

[0022] Figure 6 This is a perspective view of an example of the frame of the plasma processing apparatus provided in the plasma generation section according to an embodiment of the present invention.

[0023] Figure 7 This is a longitudinal sectional view of the plasma processing apparatus according to an embodiment of the present invention, showing a vacuum container cut along the rotation direction of the base.

[0024] Figure 8 This is a perspective view showing, enlarged, the plasma processing gas nozzle of the plasma processing apparatus according to an embodiment of the present invention located in the plasma processing area.

[0025] Figure 9 This is a top view of an example of the plasma generation section of a plasma processing apparatus according to an embodiment of the present invention.

[0026] Figure 10 This is a partial perspective view of the Faraday shield provided in the plasma generation section of the plasma processing apparatus according to an embodiment of the present invention.

[0027] Figure 11 This is a perspective view of a plasma generating apparatus according to an embodiment of the present invention.

[0028] Figure 12 This is a side view of a plasma generating apparatus according to an embodiment of the present invention.

[0029] Figure 13 This is a side view of the antenna.

[0030] Figure 14This is a diagram showing an example of a plasma processing apparatus of this embodiment equipped with an ion-capturing plate.

[0031] Figure 15 This is a diagram showing an example of an ion trapping plate.

[0032] Figure 16 This is a diagram showing an example of a movable ion trapping plate.

[0033] Figure 17 This is a diagram showing an example of the configuration of an ion trapping plate inside a vacuum container. Detailed Implementation

[0034] Hereinafter, with reference to the accompanying drawings, a method for carrying out the present invention will be described.

[0035] [Structure of the plasma processing device]

[0036] Figure 1 A schematic longitudinal sectional view showing an example of a plasma processing apparatus according to an embodiment of the present invention. Additionally, Figure 2 A schematic top view showing an example of the plasma processing apparatus of this embodiment. Furthermore, in Figure 2 For ease of explanation, the depiction of the top plate 11 has been omitted.

[0037] like Figure 1 As shown, the plasma processing apparatus of this embodiment includes: a vacuum container 1, which is generally circular in top view; and a base 2 disposed inside the vacuum container 1, having a rotation center at the center of the vacuum container 1, and used to rotate the wafer W.

[0038] Vacuum container 1 is a processing chamber used to house a wafer W and perform plasma treatment on films or the like formed on the surface of the wafer W. Vacuum container 1 includes a container body 12 and a top plate (top) 11 located opposite the recess 24 (described later) of the base 2. Furthermore, a ring-shaped sealing member 13 is provided at the periphery of the upper surface of the container body 12. The top plate 11 is configured to be detachable from the container body 12. The diameter (inner diameter) of the vacuum container 1 when viewed from above is not limited, and can be, for example, approximately 1100 mm.

[0039] A separation gas supply pipe 51 is connected to the center of the upper surface side inside the vacuum container 1. The separation gas supply pipe 51 supplies separation gas to suppress the mixing of different processing gases in the central region C inside the vacuum container 1.

[0040] The base 2 is fixed at its center to a generally cylindrical core 21. The base 2 is configured such that it rotates about a vertical axis relative to a rotation axis 22 that is connected to the lower surface of the core 21 and extends in the vertical direction. Figure 2In the example shown, the base 2 rotates freely clockwise using the drive unit 23. The diameter of the base 2 is not limited; for example, it can be set to approximately 1000 mm.

[0041] The rotating shaft 22 and the drive unit 23 are housed in the housing 20, and the flange portion on the upper surface of the housing 20 is hermetically mounted to the lower surface of the bottom part 14 of the vacuum container 1. In addition, a purge gas supply pipe 72 is connected to the housing 20, which is used to supply nitrogen or the like as a purge gas (separation gas) to the area below the base 2.

[0042] The portion of the bottom part 14 of the vacuum container 1 near the outer periphery of the core 21 is formed into a ring shape to constitute a protrusion 12a, which approaches the base 2 from below.

[0043] A circular recess 24, for mounting a wafer W with a diameter of, for example, 300 mm, is formed on the surface of the base 2 as a substrate mounting area. This recess 24 is provided at multiple locations, for example, five locations, along the rotation direction of the base 2. The recess 24 has an inner diameter slightly larger than the diameter of the wafer W, specifically about 1 mm to 4 mm larger. Furthermore, the depth of the recess 24 is configured to be approximately equal to or greater than the thickness of the wafer W. Therefore, when the wafer W is housed in the recess 24, the surface of the wafer W is at the same height as the surface of the area of ​​the base 2 where the wafer W is not mounted, or the surface of the wafer W is lower than the surface of the base 2. Moreover, regarding the depth of the recess 24, if it is deeper than the thickness of the wafer W, it will affect film deposition; therefore, a depth not exceeding about three times the thickness of the wafer W is preferable. Additionally, a through hole (not shown) is formed on the bottom surface of the recess 24, through which three lifting pins, such as those described later, are used to lift the wafer W from below to raise or lower it.

[0044] like Figure 2As shown, the first processing region P1, the second processing region P2, and the third processing region P3 are arranged separately from each other along the rotation direction of the base 2. The third processing region P3 is a plasma processing region, and therefore, it can also be referred to as the plasma processing region P3 hereafter. In addition, at a position opposite to the area through which the recess 24 of the base 2 passes, a plurality of gas nozzles 31, 32, 33, 34, 35, 41, and 42 made of, for example, quartz are arranged radially and spaced apart from each other along the circumference of the vacuum container 1. These gas nozzles 31 to 35, 41, and 42 are arranged between the base 2 and the top plate 11. In addition, these gas nozzles 31 to 34, 41, and 42 are installed, for example, horizontally extending from the outer peripheral wall of the vacuum container 1 toward the central region C and opposite to the wafer W. Furthermore, the gas nozzle 35 bends after extending from the outer peripheral wall of the vacuum container 1 toward the central region C, and extends in a straight line counterclockwise (opposite to the rotation direction of the base 2) along the central region C. Figure 2 In the example shown, plasma processing gas nozzles 33, 34, 35, 41, 32, 42, and 33 are arranged in this order from the feed port 15 (described later) clockwise (in the direction of rotation of the base 2). Furthermore, the gas supplied by the second processing gas nozzle 32 is in most cases a gas of the same nature as the gas supplied by the plasma processing gas nozzles 33-35; however, if the supply of this gas can be sufficient using the plasma processing gas nozzles 33-35, the second processing gas nozzle 32 may not be required.

[0045] Alternatively, the plasma processing gas nozzles 33-35 can be replaced by a single plasma processing gas nozzle. In this case, for example, similar to the second processing gas nozzle 32, a plasma processing gas nozzle extending from the outer peripheral wall of the vacuum container 1 toward the central region C can also be provided.

[0046] The first processing gas nozzle 31 constitutes a first processing gas supply unit. Additionally, the second processing gas nozzle 32 constitutes a second processing gas supply unit. Furthermore, plasma processing gas nozzles 33 to 35 each constitute plasma processing gas supply units. Additionally, separation gas nozzles 41 and 42 each constitute separation gas supply units.

[0047] Each nozzle 31-35, 41, 42 is connected to a gas supply source (not shown) via a flow regulating valve.

[0048] On the lower surface side (opposite to the base 2) of these nozzles 31-35, 41, 42, gas ejection holes 36 are formed at multiple locations along the radial direction of the base 2, for example at equal intervals, for ejecting the aforementioned gases. The separation distance between the lower edge of each nozzle 31-35, 41, 42 and the upper surface of the base 2 is configured, for example, to be about 1-5 mm.

[0049] The region below the first processing gas nozzle 31 is a first processing region P1 for adsorbing the first processing gas onto the wafer W. The region below the second processing gas nozzle 32 is a second processing region P2 for supplying the wafer W with a second processing gas capable of reacting with the first processing gas to generate reaction products. Additionally, the region below the plasma processing gas nozzles 33-35 is a third processing region P3 for modifying the film on the wafer W. Separation gas nozzles 41 and 42 are provided to form a separation region D that separates the first processing region P1 from the second processing region P2 and separates the third processing region P3 from the first processing region P1. Furthermore, no separation region D is provided between the second processing region P2 and the third processing region P3. This is because, in most cases, a portion of the components contained in the mixture of the second processing gas supplied to the second processing region P2 and the mixture supplied to the third processing region P3 are common to the second processing gas; therefore, it is not necessary to specifically use a separation gas to separate the second processing region P2 from the third processing region P3.

[0050] The first processing gas is supplied from the first processing gas nozzle 31 as the raw material gas constituting the main component of the desired membrane, as detailed below. For example, if the desired membrane is a silicon oxide membrane (SiO2), a silicon-containing gas such as an organoaminosilane gas is supplied. The second processing gas is supplied from the second processing gas nozzle 32 as the reaction gas capable of reacting with the raw material gas to generate reaction products. For example, if the desired membrane is a silicon oxide membrane (SiO2), an oxidizing gas such as oxygen or ozone gas is supplied. A mixed gas containing the same gas as the second processing gas and a rare gas is supplied from the plasma processing gas nozzles 33-35 to perform a modification treatment on the formed membrane. Here, the plasma processing gas nozzles 33-35 are configured to supply gas to different regions on the base 2. Therefore, the supply can also be performed in such a way that the flow rate ratio of the rare gas is different for each region, so that the modification treatment is carried out uniformly overall.

[0051] Figure 3 This is a cross-sectional view showing the plasma processing apparatus of this embodiment along concentric circles of the base. Furthermore, Figure 3 It is a cross-sectional view from the separation region D through the first processing region P1 to the separation region D.

[0052] The top plate 11 of the vacuum container 1 in the separation region D is provided with a generally fan-shaped protrusion 4. The protrusion 4 is installed on the back of the top plate 11, and a flat, lower top surface 44 (first top surface) is formed inside the vacuum container 1 as the lower surface of the protrusion 4, and a top surface 45 (second top surface) located on both sides of the top surface 44 that is higher than the top surface 44.

[0053] like Figure 2 As shown, the convex portion 4 forming the top surface 44 has a fan-shaped planar shape with the top cut off into an arc. Furthermore, a groove 43 extending radially is formed at the center of the convex portion 4, and the gas separation nozzles 41 and 42 are housed within this groove 43. Additionally, the peripheral portion of the convex portion 4 (the portion near the outer edge of the vacuum container 1) is bent into an L-shape, facing the outer end face of the base 2 and slightly separated from the container body 12, to prevent the processing gases from mixing with each other.

[0054] A nozzle cap 230 is provided above the first processing gas nozzle 31 to allow the first processing gas to flow along the wafer W, and to allow the separation gas to flow away from the vicinity of the wafer W and instead flow on the top plate 11 side of the vacuum container 1. Figure 3 As shown, the nozzle cover 230 includes: a generally box-shaped cover body 231 with an opening on its lower surface to accommodate the first processing gas nozzle 31; and a flow straightener 232, which is a plate-like body, connected to portions of the lower surface opening of the cover body 231 located upstream and downstream of the base 2 in the direction of rotation. Furthermore, the sidewall of the cover body 231 located at the rotation center of the base 2 extends toward the base 2 in a manner opposite to the top tip of the first processing gas nozzle 31. Additionally, the sidewall of the cover body 231 located at the outer edge of the base 2 has a notch formed in a manner that does not interfere with the first processing gas nozzle 31.

[0055] like Figure 2 As shown, a plasma generating device 80 is provided above the plasma processing gas nozzles 33-35 to plasmaize the plasma processing gas ejected into the vacuum container 1.

[0056] Figure 4 A longitudinal sectional view showing an example of the plasma generation unit in this embodiment. Additionally, Figure 5 An exploded perspective view showing an example of the plasma generation unit in this embodiment. Furthermore, Figure 6 A perspective view showing an example of the frame of the plasma generating section provided in this embodiment.

[0057] The plasma generating device 80 is constructed by spiraling an antenna 83, formed of metal wire or the like, in three layers around a vertical axis. Furthermore, the plasma generating device 80 is configured to surround a strip-shaped region extending radially along the base 2 when viewed from above, and to span the diameter portion of the wafer W on the base 2.

[0058] Antenna 83 is connected to a high-frequency power supply 85, for example, with a frequency of 13.56 MHz and an output power of for example, 5000 W, via a matching converter 84. Furthermore, antenna 83 is configured to be hermetically separated from the internal region of vacuum container 1. Additionally, in Figure 1 and Figure 2 The device includes a connection electrode 86 for electrically connecting the antenna 83 to the matching unit 84 and the high-frequency power supply 85.

[0059] Furthermore, the antenna 83 has a structure capable of bending up and down, and is equipped with a vertical movement mechanism that enables the antenna 83 to automatically bend up and down. Figure 2 These details are omitted here. The details will be described later.

[0060] like Figure 4 and Figure 5 As shown, an opening 11a is formed on the top plate 11 above the gas nozzles 33-35 for plasma processing, which is generally fan-shaped when viewed from above.

[0061] Furthermore, an ion-capturing plate 140 is disposed above the gas nozzles 33-35 for plasma processing. The ion-capturing plate 140 is a shielding plate used to limit the supply of generated plasma ions to the wafer W and improve the in-plane uniformity of plasma processing. Details of the ion-capturing plate 140 will be described later. First, the structural elements other than the ion-capturing plate 140, which are prerequisites for the plasma processing apparatus, will be described.

[0062] like Figure 4 As shown, an annular member 82 is hermetically provided in the opening 11a along the opening edge of the opening 11a. The frame 90, described later, is hermetically provided on the inner circumferential surface of the annular member 82. That is, the annular member 82 is hermetically provided at a position where its outer circumferential side faces the inner circumferential surface 11b of the top plate 11 facing the opening 11a, and its inner circumferential side faces the flange 90a of the frame 90, described later. Thus, by means of the annular member 82, a frame 90 made of a dielectric such as quartz is provided in the opening 11a, so that the antenna 83 is located at a position lower than the top plate 11. The bottom surface of the frame 90 constitutes the top surface 46 of the plasma processing region P3.

[0063] like Figure 6As shown, the frame 90 is formed such that the peripheral portion on the upper side extends horizontally in a flange shape to form a flange portion 90a, and when viewed from above, the central portion is recessed towards the interior region of the vacuum container 1 on the lower side.

[0064] The frame 90 is configured to span the radial diameter portion of the wafer W on the base 2 when the wafer W is located below the frame 90. Furthermore, a sealing member 11c, such as an O-ring, is provided between the annular member 82 and the frame 90.

[0065] The internal atmosphere of the vacuum container 1 is made airtight by means of the annular member 82 and the frame 90. Specifically, the annular member 82 and the frame 90 are inserted into the opening 11a, and then the frame 90 is pressed downwards and circumferentially by a pressing member 91 formed in a frame shape along the upper surface of the annular member 82 and the contact portion between the annular member 82 and the frame 90. The pressing member 91 is then fixed to the top plate 11 using bolts (not shown). Thus, the internal atmosphere of the vacuum container 1 is made airtight. Furthermore, in Figure 5 For simplicity, the annular member 82 is omitted in the diagram.

[0066] like Figure 6 As shown, a protrusion 92 extending vertically toward the base 2 is formed on the lower surface of the frame 90 in such a way that it surrounds the processing area P3 on the lower side of the frame 90 in the circumferential direction. Furthermore, the aforementioned plasma processing gas nozzles 33-35 are housed in the area enclosed by the inner circumferential surface of the protrusion 92, the lower surface of the frame 90, and the upper surface of the base 2. In addition, the protrusion 92 located at the base end (inner wall side of the vacuum container 1) of the plasma processing gas nozzles 33-35 has a notch formed in a generally arcuate shape along the outline of the plasma processing gas nozzles 33-35.

[0067] like Figure 4 As shown, protrusions 92 are formed circumferentially on the lower side (third processing region P3) of the frame 90. The sealing member 11c is isolated from the plasma by utilizing these protrusions 92. Therefore, even if plasma diffuses from the third processing region P3, for example, toward the sealing member 11c, it will be deactivated before reaching the sealing member 11c because it travels below the protrusions 92.

[0068] In addition, such as Figure 4As shown, plasma processing gas nozzles 33-35 are located in the third processing area P3 below the frame 90 and are connected to the argon supply source 120, the helium supply source 121, and the oxygen supply source 122. Furthermore, flow controllers 130, 131, and 132 are respectively provided between the plasma processing gas nozzles 33-35 and the argon, helium, and oxygen supply sources 120, 121, and 122. Ar, He, and O2 gases are supplied from the argon, helium, and oxygen supply sources 120, 121, and 122 to each plasma processing gas nozzle 33-35 at a predetermined flow ratio (mixing ratio) via the flow controllers 130, 131, and 132, respectively, and the flow ratio of Ar, He, and O2 gases is determined according to the region being supplied.

[0069] Furthermore, if there is only one plasma processing gas nozzle, for example, the mixture of Ar gas, He gas and O2 gas described above can be supplied to one plasma processing gas nozzle.

[0070] Figure 7 This is a longitudinal sectional view showing the vacuum container 1 cut along the rotation direction of the base 2. (See diagram below.) Figure 7 As shown, during plasma processing, the base 2 rotates clockwise. Therefore, N2 gas, accompanying the rotation of the base 2, intrudes from the gap between the base 2 and the protrusion 92 towards the lower side of the frame 90. Consequently, gas is ejected from the lower side of the frame 90 into the gap to prevent N2 gas from intruding into the lower side of the frame 90 through the gap. Specifically, as... Figure 4 and Figure 7 As shown, the gas ejection port 36 of the plasma processing gas nozzle 33 is arranged facing the gap, that is, upstream and downward in the rotational direction of the base 2. The orientation angle θ of the gas ejection port 36 of the plasma processing gas nozzle 33 relative to the vertical axis can also be as follows: Figure 7 For example, the angle is about 45°, but it can also be about 90° opposite to the inner surface of the protrusion 92. In other words, the orientation angle θ of the gas ejection port 36 can be set within a range of about 45° to 90°, which can properly prevent the intrusion of N2 gas, depending on the application.

[0071] Figure 8 This is a magnified perspective view of the plasma processing gas nozzles 33-35 located in the plasma processing region P3. (See diagram below.) Figure 8As shown, the plasma processing gas nozzle 33 is a nozzle capable of covering the entire recess 24 of the wafer W and supplying plasma processing gas to the entire surface of the wafer W. The plasma processing gas nozzle 34 is positioned slightly above the plasma processing gas nozzle 33, roughly overlapping it, and has a length approximately half that of the plasma processing gas nozzle 33. The plasma processing gas nozzle 35 extends from the outer peripheral wall of the vacuum container 1 along a radius downstream of the fan-shaped plasma processing region P3 in the rotational direction relative to the base 2, and then bends linearly along the central region C after reaching the vicinity of the central region C. For ease of distinction, the plasma processing gas nozzle 33 covering the entire surface may be referred to as the base nozzle 33, the plasma processing gas nozzle 34 covering only the outer surface as the outer nozzle 34, and the plasma processing gas nozzle 35 extending inward as the axial nozzle 35.

[0072] The base nozzle 33 is a gas nozzle used to supply plasma processing gas to the entire surface of the wafer W, such as... Figure 7 As described above, plasma processing gas is ejected toward the protrusion 92, which forms the side of the plasma processing area P3.

[0073] In addition, the outer nozzle 34 is a nozzle used to supply plasma processing gas to the outer region of the wafer W.

[0074] The axial nozzle 35 is a nozzle used to supply plasma processing gas to the central region of the wafer W near the axial side of the substrate 2.

[0075] Furthermore, if only one gas nozzle is used for plasma processing, only the base nozzle 33 needs to be installed.

[0076] Next, the Faraday shield 95 of the plasma generating device 80 will be described in more detail. For example... Figure 4 and Figure 5 As shown, a grounded Faraday shield 95 is housed on the upper side of the frame 90. The Faraday shield 95 is made of a conductive plate-shaped metal plate, such as copper, formed in a manner that generally follows the internal shape of the frame 90. The Faraday shield 95 has a horizontal surface 95a that is horizontally fixed along the bottom surface of the frame 90 and a vertical surface 95b that extends circumferentially upward from the outer end of the horizontal surface 95a. It can also be configured to be approximately hexagonal when viewed from above.

[0077] Figure 9This is a top view of an example of a plasma generating device 80, omitting the detailed construction of the antenna 83 and the up-and-down movement mechanism. Figure 10 A partial perspective view is shown of a Faraday shield 95 provided in the plasma generating device 80.

[0078] When viewed from the rotation center of the base 2, the upper edges of the right and left sides of the Faraday shield 95 extend horizontally to the right and left respectively to form support portions 96. Furthermore, a frame-like body 99 is provided between the Faraday shield 95 and the frame 90. This frame-like body 99 supports the support portion 96 from below and is supported by the flange portion 90a on the side of the frame 90 near the center region C and the flange portion 90a on the side of the outer edge of the base 2, respectively.

[0079] When an electric field reaches wafer W, electrical wiring and other components formed inside wafer W can sometimes suffer electrical damage. Therefore, as... Figure 10 As shown, a number of slits 97 are formed on the horizontal plane 95a to prevent the electric field component in the electric field and magnetic field (electromagnetic field) generated by the antenna 83 from going to the wafer W below, and to allow the magnetic field to reach the wafer W.

[0080] like Figure 9 and Figure 10 As shown, slits 97 are formed circumferentially below the antenna 83 in a direction orthogonal to the winding direction of the antenna 83. Here, the slits 97 are formed with a width less than 1 / 10000 of the wavelength corresponding to the high frequency supplied to the antenna 83. Furthermore, grounded conductive paths 97a formed of conductors or the like are arranged circumferentially at one and the other ends of each slit 97 in the long side direction, sealing off the opening ends of these slits 97. In the Faraday shield 95, an opening 98 is formed in the center of a region offset from the region where these slits 97 are formed, i.e., the region where the antenna 83 is wound, for confirming the luminescence state of the plasma by means of this region. Furthermore, in Figure 2 For simplicity, slit 97 is omitted, and the example of the formation area of ​​slit 97 is represented by a dashed line.

[0081] like Figure 5 As shown, an insulating plate 94, made of quartz or the like, with a thickness of approximately 2 mm, is stacked on the horizontal surface 95a of the Faraday shield 95 to ensure insulation between it and the plasma generating device 80 mounted above the Faraday shield 95. That is, the plasma generating device 80 is configured to cover the interior of the vacuum container 1 (the wafer W on the base 2) through the frame 90, the Faraday shield 95, and the insulating plate 94.

[0082] Next, an example of the antenna device 81 for holding the antenna and the plasma generating device 80 according to an embodiment of the present invention will be described.

[0083] Figure 11 This is a perspective view of the antenna device 81 and the plasma generating device 80. Figure 12 This is a side view of the antenna device 81 and the plasma generating device 80.

[0084] The antenna device 81 includes an antenna 83, a connecting electrode 86, a vertical moving mechanism 87, a linear encoder 88, and a fulcrum fixture 89.

[0085] In addition, the plasma generating device 80 also includes an antenna device 81, a matching device 84, and a high-frequency power supply 85.

[0086] Antenna 83 includes antenna members 830, connecting members 831, and spacers 832. Antenna 83 is generally configured in a spiral or rotating shape, and when viewed from above, it is a slender ring with a long side and a short side (or width) direction. As a top-view shape, it has a frame shape that is approximately an ellipse with angles or a chamfered rectangle. This rotating shape of antenna 83 is formed by connecting antenna members 830. Antenna members 830 are components constituting a part of antenna 83, and antenna 83 is formed by connecting the ends of multiple smaller antenna members 830 extending along the rotating shape to each other. Antenna members 830 include a straight portion 8301 with a straight shape and a curved portion 8302 with a curved shape for connecting the straight portions 8301 to each other in a curved manner.

[0087] Therefore, by combining and connecting the straight portion 8301 and the curved portion 8302, the two ends 830a and 830b and the central portions 830c and 830d of the antenna component 830 are connected to form a rotating shape as a whole. Figure 11 In the antenna 83, as a whole, the two ends 830a and 830b have a near-circular arc shape, while the central portions 830c and 830d have a straight line shape. Thus, the straight-shaped antenna members 830c and 830d in the center connect the near-circular-shaped antenna members 830a and 830b at the two ends, and the central antenna members 830c and 830d are roughly parallel to each other. The antenna 83 as a whole has a shape where antenna members 830c and 830d form the long side and antenna members 830a and 830b form the short side.

[0088] In addition, such as Figure 11As shown, antenna components 830a and 830b are formed by connecting three straight sections 8301 to each other through two curved sections 8302, creating an approximately arc-shaped configuration. Antenna component 830c is composed of a longer straight section 8301. Furthermore, as... Figure 11 and Figure 12 As shown, the antenna component 830d is constructed by connecting two longer straight sections 8301 and a shorter straight section between them with a height difference between them by means of two smaller curved sections 8302.

[0089] The antenna component 830 is formed in a multi-layered manner to create a rotatable shape. Figure 11 , Figure 12 The image shows an antenna component 830 forming a three-layered rotating shape.

[0090] The connecting member 831 is a component used to connect adjacent antenna components 830 to each other, and is made of a conductive and deformable material. The connecting member 831 may also be made of, for example, a flexible substrate, and may be made of copper. Copper is a raw material with high conductivity and flexibility, therefore, it is suitable for connecting antenna components 830 to each other.

[0091] Because the connecting member 831 is made of a flexible material, the antenna member 830 can be bent using the connecting member 831 as a fulcrum. Therefore, the antenna member 830 can be maintained in a bent state at the location of the connecting member 831, allowing for various changes in the three-dimensional shape of the antenna 83. The distance between the antenna 83 and the wafer W affects the intensity of the plasma processing; there is a tendency for the intensity of the plasma processing to increase if the antenna 83 is brought closer to the wafer W, and to decrease if the antenna 83 is moved further away from the wafer W.

[0092] Furthermore, the method for determining the shape of antenna 83 and the details of its shape will be described later.

[0093] When the wafer W is placed on the recess 24 of the base 2 and the base 2 is rotated for plasma processing, the center side of the base 2 moves slower and the outer periphery moves faster because the wafer W is arranged along the circumference of the base 2. Therefore, there is a tendency for the intensity (or amount) of plasma processing on the center side of the wafer W, which is irradiated by plasma for a longer period, to be higher than the intensity of plasma processing on the outer periphery. To correct this, for example, if the shape is such that the antenna member 830a at the end arranged on the center side is bent upwards and the antenna member 830b arranged on the outer periphery is bent downwards, the intensity of plasma processing on the center side can be reduced and the intensity of plasma processing on the outer periphery can be increased, thus uniformizing the overall amount of plasma processing in the radial direction of the base 2.

[0094] In addition, Figure 11 In this configuration, four connecting members 830a to 830d are provided to connect the four antenna components 830a to 830d. ​​However, the number of antenna components 830 and connecting members 831 can be increased or decreased depending on the application. Alternatively, at a minimum, antenna components 830a and 830b with two ends can be configured as a long U-shaped structure extending not only to the ends but also to the center, with two connecting members 831 connecting the two antenna components 830a and 830b. Furthermore, if a more varied shape of the antenna 83 is desired, it can be configured with four antenna components 830 in the center to further increase the bendable portion.

[0095] In any case, it is preferable that the positions of the opposing connecting members 831 are the same in the long side direction, that is, the lengths of the opposing antenna members 830 in the long side direction are equal. As described above, when adjusting the height of the antenna 83 in the long side direction, the bent portions are preferably configured to be opposite each other in the short side direction and aligned in the long side direction. In this embodiment, the connecting member 831 connecting antenna members 830a and 830c and the connecting member 831 connecting antenna members 830a and 830d are configured to be opposite each other in the short side direction and at the same position in the long side direction. Similarly, the connecting member 831 connecting antenna members 830b and 830c and the connecting member 830b and 830d are also configured to be opposite each other in the short side direction and at the same position in the long side direction. By setting it in this way, the shape of the antenna 83 can be changed in a way that adjusts the intensity of plasma treatment in the long side direction.

[0096] However, if it is desired to tilt the bent part to create a parallelogram-like deformation, the following structure is also possible: the connecting members 831 are not facing each other directly in the short side direction, but facing each other in the tilt direction, and the positions of the connecting members 831 in the long side direction are set at different positions on the antenna member 830c side and the antenna member 830d side.

[0097] Spacer 832 is a component used to separate the upper and lower layers of the multilayer antenna component 830, so that even if the antenna 83 is deformed, the upper and lower layers will not come into contact and cause a short circuit.

[0098] The vertical movement mechanism 87 is a mechanism for moving the antenna component 830 vertically. The vertical movement mechanism 87 includes an antenna holding part 870, a driving part 871, and a frame 872. The antenna holding part 870 holds the antenna 83, and the driving part 871 is a driving part for moving the antenna 83 vertically using the antenna holding part 870. The antenna holding part 870 only needs to be able to hold the antenna component 830 of the antenna 83, and can have various structures, for example, such as... Figure 12 As shown, it can also be a structure that covers the area around the antenna component 830 and maintains the antenna component 830.

[0099] The drive unit 871 is also simple; it only needs to be able to move the antenna component 830 up and down. Various drive components can be used, for example, a pneumatically driven cylinder can also be used. Figure 12 The example shown is an example in which a cylinder is applied to the drive unit 871 of the vertical movement mechanism 87. Alternatively, a motor or the like can also be used in the vertical movement mechanism 87.

[0100] The frame 872 is a support for holding the drive unit 871 in a proper position. Furthermore, the antenna holding part 870 is held by the drive unit 871.

[0101] The vertical movement mechanism 87 is individually provided on at least two of the multiple antenna components 830a to 830d. ​​In this embodiment, the deformation of the antenna 83 is not adjusted by a worker, but is automatically performed using the vertical movement mechanism 87. Therefore, it is preferable to provide a vertical movement mechanism 87 individually on each of the antenna components 830a to 830d, and to perform independent operations to deform the antenna 83 into various shapes. Therefore, it is preferable to provide a vertical movement mechanism 87 individually on each of the antenna components 830a to 830d, or, if not on all antenna components 830a to 830d, to provide a vertical movement mechanism 87 on at least two of the antenna components 830a to 830d.

[0102] exist Figure 11 and Figure 12In the diagram, only one vertical movement mechanism 87 is shown, but the antenna members 830a to 830d, which are the objects of bending, are each provided with a separate vertical movement mechanism 87. For example, if a vertical movement mechanism 87 for moving antenna member 830a vertically is provided on the center side in the rotation direction of the base 2, and vertical movement mechanisms 87 for moving antenna members 830c and 830d vertically are also provided, then antenna members 830a, 830c, and 830d can be deformed into any shape. In this case, for example, if it is desired to bend the antenna member 830a at the center end upwards, the following action can be performed: the corresponding vertical movement mechanism 87 lifts the antenna member 830a, and the corresponding vertical movement mechanism 87 fixes or pulls down the antenna members 830c and 830d, thereby deforming the antenna 83 by means of multiple vertical movement mechanisms 87 working together. When the connecting member 831 is flexible enough that the antenna 83 can be bent simply by the up-and-down movement of the corresponding up-and-down moving mechanism 87, such an action is not necessarily required. Although the connecting member 831 can deform, when the deformation requires a certain amount of force, the bending action of the antenna 83 can also be performed by using multiple up-and-down moving mechanisms 87 in cooperation.

[0103] Furthermore, using the connecting member 831 as a fulcrum, the angle formed by the antenna members 830a to 830d on both sides of the connecting member 831 and the connecting member 831 is changed, thereby bending the antenna 83.

[0104] The linear encoder 88 is a device that detects position on a straight axis and outputs position information. This allows for accurate measurement of the distance between the antenna member 830a and the upper surface of the Faraday shield 95. Furthermore, the linear encoder 88 can be installed at any location where accurate position information is desired, and multiple encoders can be installed. Additionally, the linear encoder 88 can be any type—optical, magnetic, or electromagnetic induction—as long as it can measure the position and height of the antenna 83. Moreover, as long as it can measure the position and height of the antenna 83, a height measuring component other than the linear encoder 88 can be used.

[0105] The fulcrum fixture 89 is used to fix the lowest antenna member 830 into a rotatable component. This facilitates tilting of the antenna 83. Furthermore, the fulcrum fixture 89 is generally provided to support the lowest antenna member 830b at its outer periphery. This is because, as described above, there are many cases where the antenna 83 is deformed to have a higher center side. However, it is not necessary to provide the fulcrum fixture 89; preferably, a vertical movement mechanism 87 for moving the antenna member 830b vertically is used instead.

[0106] The connecting electrode 86 includes an antenna connection portion 860 and an adjustment busbar 861. The connecting electrode 86 is a connection wiring that supplies high-frequency power output from the high-frequency power supply 85 to the antenna 83. The antenna connection portion 860 is a connection wiring that is directly connected to the antenna 83. The adjustment busbar 861 is a portion designed with elasticity to absorb deformation when the antenna connection portion 860 moves up and down due to the up and down movement of the antenna 83. Since it is an electrode, it is entirely made of conductive materials such as metal.

[0107] Thus, an antenna device 81 and a plasma generating device 80 that can automatically deform the shape of the antenna 83 into any shape can also be used.

[0108] Figure 13 This is a side view of antenna 83 according to an embodiment of the present invention. Figure 13 As shown, the bending angle of the antenna component 830 can be varied by using the connecting member 831 as a fulcrum, and the height of the antenna component 830 can also be varied according to the location.

[0109] However, if the height of the antenna component 830a is too high, the distance between the bottom surface of the frame 90 and the antenna component 830a will be too long, making it difficult for the plasma power to reach the vacuum container 1. This can lead to problems such as difficulty in plasma ignition and easy deactivation. Specifically, for example, if the height of the antenna component 830a is set to 20mm or more, such phenomena are likely to occur.

[0110] Therefore, it is necessary to homogenize the plasma intensity between the central axis and the outer periphery of the rotating stage 2 without making the distance between the antenna component 830a and the bottom surface of the frame 90 too large.

[0111] According to this viewpoint, the height of the antenna component 830a is reduced as much as possible, and any shortfall in adjustment is compensated for by installing an ion trapping plate 140 inside the vacuum container 1 (see reference). Figure 4 ).

[0112] [Ion Capture Plate]

[0113] Figure 14 This diagram shows an example of a plasma processing apparatus according to this embodiment, equipped with an ion-capturing plate. Figure 14 The plasma processing region P3 is shown in magnification in the image. Figure 14 The plasma processing area P3 is shown in perspective; the frame 90° is transparent, therefore it is synonymous with the top view. Figure 4 As described above, the ion trapping plate 140 is disposed inside the vacuum container 1.

[0114] like Figure 14As shown, for example, the ion-capturing plate 140 is configured to partially overlap with the shape of the bottom surface of the frame 90. Figure 14 In the ion trapping plate 140, a portion of the coverage area 83c of the antenna 83 between location 83a and location 83b is covered by the ion trapping plate 140.

[0115] The coverage area 83c primarily includes the region of antenna 83 near the center of the rotating stage 2, but excludes the outermost periphery of antenna 83. That is, it becomes such that the region near the center of antenna 83 is primarily covered by the ion trapping plate 140, while the outer periphery of antenna 83 is less covered or completely uncovered.

[0116] Thus, by placing an ion trapping plate 140 in the area overlapping with the antenna 83, ions generated by the plasma can be blocked, thereby reducing the plasma's oxidation capacity. Therefore, the ion trapping plate 140 can also be referred to as an ion baffle or ion shield. As a result, even if the set height of the antenna 83 (antenna member 830a) is reduced, the oxidation capacity of the region on the central axis side of the rotating stage 2 can be reduced, and the plasma oxidation capacity in the radial direction can be made uniform.

[0117] Furthermore, the ion trapping plate 140 does not necessarily need to trap ions; it is sufficient to simply shield (block) ions. It is sufficient to locally restrict the supply of oxidizing gas ions to the wafer W in the region on the central axis side of the antenna 83.

[0118] For example, the height of the antenna component 830a can be set to 15mm, 10mm, 0mm, or less than 15mm to prevent plasma deactivation and ignition failure.

[0119] Furthermore, the shape of the ion baffle 140 and the area overlapping with the antenna 83 can be configured in various ways depending on the application. Figure 14 In the case of the ion capture plate 140, the top view shape is configured such that it is tilted across the antenna 83, but it can be deformed in various ways depending on the application.

[0120] Figure 15 This is a diagram showing an example of an ion-capturing plate 140. The ion-capturing plate 140 has a side 141 extending circumferentially along the central axis of the rotating stage 2, and a side 145 extending radially. Furthermore, in a manner connecting the end of the central axis side of the side 141 and the end of the outer periphery of the radially extending side 145, there is a side 142 extending obliquely in the radial direction and a side 143 extending circumferentially. Sides 142 and 143 are connected curvilinearly by a rounded corner portion 144, forming a curved angle.

[0121] The ion trapping plate 140 is preferably configured as a plate, as described in the text. This is because the space inside the vacuum container 1 is limited, and a thinner plate shape is sufficient to achieve the function of shielding or trapping ions.

[0122] The material of the ion trapping plate 140 can be appropriately used depending on the application, as long as it can block or trap ions. For example, quartz can also be used. Considering that the frame 90 is also made of quartz, which can withstand high temperatures and is not prone to pollution, quartz is the preferred material.

[0123] Figure 16 This is a diagram showing an example of a movable ion-capturing plate 146. (See diagram for example.) Figure 16 As shown, a pivot 150 can be set, and the movable ion capture plate 146 can be rotated and moved around the pivot 150 to change the range of the coverage antenna 83.

[0124] When configured as a movable ion-capturing plate 146, it is preferable to make the overall structure relatively small, and to configure it in a shape that allows it to move within the plasma processing region P3. Figure 16 In the middle, it is made of a thinner tip and the overall width is smaller than that of the ion capture plate 140.

[0125] By configuring it as a movable type, the amount of ions captured and blocked can be adjusted according to the process, and the oxidation capacity can be finely adjusted. Thus, the movable ion capture plate 146 can also be configured in this way depending on the application.

[0126] Figure 17 This is a diagram showing an example of the configuration of an ion trapping plate inside a vacuum container 1. Figure 17 (a) shows an example where the ion trapping plate 147 is located in the area on the left side of the frame 90. Thus, the ion trapping plate 147 can be configured either left or right, as long as it can effectively cover the area on the central axis of the antenna 83.

[0127] Figure 17 (b) is a partial cross-sectional view showing an example of the vertical configuration of a plasma processing apparatus equipped with an ion-capturing plate 147. Figure 17 As shown in (b), the ion trapping plate 147 is disposed above the plasma processing gas nozzles 33-35. The ion trapping plate 147 may also have multiple claws 148 and be fixed to the plasma processing gas nozzles 33-35. Figure 17 In (b), an example is given in which the ion trapping plate 147 is placed on the plasma processing gas nozzles 33-35, but it can also be supported by other support members and disposed above the plasma processing gas nozzles 33-35 at an open interval.

[0128] In addition, ion trapping plates 140 and 146 can also be installed inside the vacuum container 1, just like ion trapping plate 147.

[0129] By setting ion-capturing plates 140, 146, and 147 on or above the plasma processing gas nozzles 33-35, ions can be captured without obstructing the flow of the plasma processing gas, and the oxidation capacity can be adjusted.

[0130] This allows for a reduction in the tilt of antenna 83, maintaining the plasma in a stable state.

[0131] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments, and various modifications and substitutions can be applied to the above embodiments without departing from the scope of the present invention.

Claims

1. A plasma processing apparatus, wherein, The plasma processing device has the following features: Processing room; A rotating stage, located within the processing chamber, is capable of circumferentially placing a substrate. A processing gas supply nozzle is provided, which is capable of supplying processing gas to the rotary table; A plasma antenna, positioned on the processing chamber at least partially covering the processing gas supply nozzle; and An ion trapping plate is positioned above the processing gas supply nozzle within the processing chamber, at least partially overlapping with the plasma antenna. The plasma antenna is configured to cover the rotary table in the radial direction. The ion-capturing plate has a top-view shape that extends in the radial direction. The ion trapping plate is configured such that the region of the ion trapping plate overlapping with the plasma antenna is wider on the central side of the rotating stage than on the outer periphery side.

2. The plasma processing apparatus according to claim 1, wherein, The plasma antenna has a spiral shape extending along the radial direction. The ion-capturing plate is configured to obliquely cover a portion of the plasma antenna.

3. The plasma processing apparatus according to claim 1 or 2, wherein, The plasma antenna is configured at an angle such that the portion near the center side of the rotating stage is higher than the portion near the outer periphery side.

4. The plasma processing apparatus according to claim 1 or 2, wherein, The ion capture plate is disposed on the processing gas supply nozzle.

5. The plasma processing apparatus according to claim 1 or 2, wherein, The ion-capturing plate is composed of components capable of shielding ions.

6. The plasma processing apparatus according to claim 5, wherein, The ion-capturing plate is made of quartz.

7. The plasma processing apparatus according to claim 1 or 2, wherein, The ion-capturing plate is movable.

8. The plasma processing apparatus according to claim 7, wherein, The ion-capturing plate is fixed on the central side by a pivot, allowing for angle adjustment.

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