Plasma processing apparatus and plasma processing method

Abstract

Provided is a technique for preventing a plasma processing failure in the vicinity of the outer periphery of a substrate to be processed. Provided is a technique comprising: a processing chamber in which a substrate to be processed is subjected to plasma processing; a high-frequency power supply that supplies microwave power via the waveguide tube; a dielectric plate which is disposed above the processing chamber and through which the microwaves pass; a sample stage on which a substrate to be processed is placed; an electromagnet configured to surround the periphery of the processing chamber and generate a first static magnetic field; a static magnetic field generating device disposed below the substrate to be processed; and a control device for controlling the electromagnet, in which the static magnetic field generation device generates the second static magnetic field in the first static magnetic field in a direction in which the static magnetic field parallel to the central axis of the processing chamber is enhanced, and the control device controls the electromagnet such that the angle of the magnetic lines of the third static magnetic field with respect to the surface to be processed of the substrate to be processed becomes a desired angle. The third static magnetic field is a static magnetic field formed by overlapping the first static magnetic field and the second static magnetic field.

Description

Technical Field

[0001] The present disclosure relates to a plasma processing device and a plasma processing method, and in particular to a plasma processing device and a plasma processing method for generating plasma in a processing chamber by using the interaction between microwaves and a static magnetic field to perform plasma processing on a substrate to be processed arranged in the processing chamber. Background Art

[0002] Plasma processing devices are used in the production of semiconductor integrated circuit elements (hereinafter also referred to as semiconductor elements or elements) that constitute semiconductor integrated circuits. In order to improve the performance of elements and reduce costs, the miniaturization of elements is constantly progressing. In the past, due to the two-dimensional miniaturization of elements, the number of elements that can be manufactured by one processed substrate (semiconductor wafer, semiconductor substrate, also simply referred to as substrate) increased, thereby reducing the manufacturing cost of each element, and the performance of semiconductor integrated circuits was improved by miniaturization effects such as shortening the wiring length. However, if the size of the semiconductor element becomes nanometer-level, which is close to the size of an atom, the difficulty of two-dimensional miniaturization becomes significantly higher, and new materials and three-dimensional element structures must be used to deal with it. Due to these changes, the difficulty of manufacturing is further increased, and the number of manufacturing processes increases, and the increase in manufacturing costs has become a serious problem.

[0003] If tiny foreign matter or contaminants are attached to semiconductor integrated circuit components during manufacturing, it will become a fatal defect. Therefore, semiconductor integrated circuit components are manufactured in a clean room where foreign matter and contaminants are removed and the temperature and humidity are controlled to the best. With the miniaturization of components, the cleanliness of the clean room required for manufacturing increases, and the construction and maintenance of the clean room require huge expenses. Therefore, it is sought to efficiently utilize the clean room space for production. From this point of view, semiconductor manufacturing equipment strictly seeks miniaturization and low cost.

[0004] In addition, the in-plane uniformity of the plasma treatment of the substrate to be processed is also very important. In the manufacture of semiconductor integrated circuit elements, a disk-shaped silicon wafer with a diameter of 300 mm is often used as the substrate to be processed. A large number of semiconductor integrated circuit elements are made on this silicon wafer. If the in-plane uniformity of the plasma treatment is poor, the number of good products (good semiconductor chips) that meet the product specifications that can be obtained from one silicon wafer will decrease. Similarly, the stability of the plasma treatment of each substrate to be processed is also very important. When the quality of the plasma treatment is unstable, for example, when the quality changes over time, the proportion of good products is also reduced.

[0005] Among the plasma processing devices that generate plasma by electromagnetic waves, plasma processing devices that use microwaves with a frequency of several GHz, typically 2.45 GHz, as electromagnetic waves are widely used. In particular, there are plasma processing devices that use the electron cyclotron resonance (ECR) phenomenon caused by combining microwaves and a static magnetic field. In this plasma processing device, there are excellent features such as being able to generate plasma relatively stably even under conditions such as extremely low pressure, which are usually difficult to generate plasma, and being able to control the distribution of plasma by the distribution of the static magnetic field.

[0006] Generally, it is known that electrons moving in a plasma to which a static magnetic field is applied are subjected to a force called the Lorentz force, and diffusion in a direction perpendicular to the static magnetic field is suppressed. Similarly, it is known that ions in a plasma diffuse together due to an electric field generated between them and the electrons, which is a phenomenon called bipolar diffusion. Through these effects, a static magnetic field is applied to the plasma, and diffusion in a direction perpendicular to the static magnetic field is suppressed, thereby controlling the density distribution of the plasma.

[0007] In the plasma processing apparatus used in the manufacture of semiconductor integrated circuit elements, plasma called low-temperature plasma is often used, in which the temperature of electrons and ions is greatly different. Although it depends on the plasma generation conditions, in low-temperature plasma, the temperature of electrons is said to be in the order of several eV, and the temperature of ions is in the order of 0.1 eV. Usually, in plasma, the density of electrons and ions is roughly equal, and they remain electrically neutral. However, near the surface where the plasma contacts the substrate to be processed and the processing chamber, the high-speed electrons escape to the wall due to the high temperature, creating a region called the sheath where the remaining ions become excessive.

[0008] In the sheath, a strong electric field caused by charge separation is locally generated. In particular, the sheath formed at the interface of the processed substrate will have a great impact on the quality of plasma processing. If high-frequency power is applied to the processed substrate, a DC bias voltage is generated in the processed substrate according to the voltage and current characteristics of the sheath, which can control the energy of the ions in the plasma incident on the surface of the processed substrate. By optimizing this energy, for example in the case of plasma etching, the quality of plasma processing such as etching speed and shape can be improved. For example, in a plasma processing device, a high-frequency power supply device (radio frequency (RF) power supply device) with a frequency of 400kHz to 13.56MHz is electrically connected to the processed substrate to apply a high-frequency bias to the sheath. When making the connection, an automatic matcher is often used to eliminate power mismatch.

[0009] Theoretical treatments related to the sheath are described in many known documents. For example, Non-Patent Document 1 describes that ions are incident on the interface between plasma and the sheath at a speed greater than the Bohm speed shown in Formula 1.

[0010] V Bohm =√((eTe) / mi)…Formula 1

[0011] Here, VBohm: Bohm velocity (m / s), e: electron charge (=1.602×10-19C), m i : mass of ions (kg), T e : Electron temperature (V).

[0012] That is, it is known that in the sheath layer connected to the substrate to be processed, ions are incident on the sheath end at an initial velocity higher than the Bohm velocity, and are accelerated by the electric field of the sheath layer to reach the substrate to be processed. The electric field of the sheath layer can be controlled by high-frequency bias, which can improve the quality of plasma processing.

[0013] In a plasma processing device using the aforementioned electron cyclotron resonance (ECR), microwaves are often injected from a region with a strong static magnetic field in parallel with the static magnetic field, and further, microwaves are often injected as circularly polarized waves (hereinafter referred to as R waves) whose electric field rotates right-handedly relative to the static magnetic field. This is because the R wave is not cut off in a strong magnetic field domain exceeding the ECR condition, and can also propagate in a high-density domain, which is clear in theory. Here, the so-called ECR condition refers to a static magnetic field in which the electron cyclotron frequency and the microwave frequency are consistent. When the microwave frequency is 2.45GHz, the ECR condition is equivalent to a static magnetic field of 875 Gauss. That is, the R wave injected from a strong magnetic field domain above the ECR condition can also propagate in the plasma when a high-density plasma is generated, so that the microwave power can be propagated to the region causing ECR (the surface of the electron cyclotron resonance (ECR): called the ECR surface), so that it can be absorbed efficiently. Furthermore, the surface of the processed surface of the processed substrate is opposite to the surface into which the microwave is injected, and is often arranged in a weak magnetic field domain roughly perpendicular to the static magnetic field.

[0014] Generally, when a semiconductor integrated circuit element is manufactured using a plasma etching device, the processing conditions are adjusted according to the film thickness and type of the film to be processed so as to optimize the processing quality of the etching process. The processing conditions include the type and flow rate of the gas used in the etching process, the pressure of the plasma processing chamber, the power for plasma generation, the RF bias power given to the processed substrate, etc. In particular, in an etching device using an ECR plasma source, the diffusion and generation area of ​​the plasma can be controlled by a static magnetic field, and the distribution of the static magnetic field is an important parameter. In ECR plasma, it is believed that the absorption of microwave power into the plasma is strongly caused locally on the ECR surface, and in particular, the position of the ECR surface is important in controlling the generation area of ​​the plasma. It is believed that the generation of ions and chemically active free radicals is actively carried out near the ECR surface. By adjusting the distance between the ECR surface and the processed surface of the processed substrate, the ratio and density of ions and free radicals on the processed surface of the processed substrate can be adjusted, and the optimization of the plasma processing quality such as the processing shape can be achieved.

[0015] In plasma etching, the gas flow rate and pressure are also important parameters. By applying RF bias to the substrate to be processed and attracting ions in the plasma, the etching rate on the surface of the substrate to be processed where the ions collide (the processed surface of the substrate to be processed) can be increased, and the anisotropy of the processed shape can be improved. Under low pressure, since the frequency of collision between ions and neutral gas molecules is reduced, the linearity of ions increases. Therefore, in order to improve the anisotropy of the processed shape, etching treatment under low pressure is effective. In addition, if the gas flow rate is increased, not only the supply of active species required for the etching reaction increases, but also the re-adhesion of the reaction products to the surface of the substrate to be processed is reduced, which is beneficial in increasing the etching rate. Etching in such a low-pressure and high-flow gas is beneficial for high-quality processing. However, low pressure and high gas flow are in a trade-off relationship that is difficult to take into account at the same time. Therefore, in a plasma etching device, it is important to improve the vacuum exhaust capacity of the plasma etching device.

[0016] exist Figure 1An etching device 0100 is shown as a comparative example of a plasma processing device using ECR. An electromagnet 0102 is arranged around a roughly cylindrical plasma processing chamber 0107, and a static magnetic field for causing ECR can be applied to the plasma processing chamber 0107. The electromagnet 0102 is composed of a multi-stage solenoid coil. A yoke 0110 is arranged around the outer side of these solenoid coils. By adjusting the strength of the magnetic field generated by each solenoid coil, the static magnetic field distribution in the processing chamber 0107 can be controlled. Microwaves are supplied to the cavity 0104 from a circular waveguide 0101 arranged along the central axis of the plasma processing chamber 0107. The microwaves are shaped into electromagnetic field distribution by the cavity 0104, and are introduced into the plasma processing chamber 0107 from the cavity 0104 through the microwave introduction window 0105 and the shower plate 0106 arranged on the surface opposite to the surface of the processed surface of the processed substrate 0103 inside the plasma processing chamber 0107. Microwaves with a frequency of 2.45 GHz are mostly used. The gas used in the etching process is supplied to the interior of the processing chamber 0107 from the gas supply device not shown in the figure through the microscopic gap between the microwave introduction window 0105 and the shower plate 0106 not shown in the figure and the plurality of fine gas supply holes not shown in the figure provided on the shower plate 0106. Quartz is mostly used for the microwave introduction window 0105 and the shower plate 0106 as a material that transmits microwaves and is unlikely to have adverse effects on the plasma processing. In addition, the inner surface of the plasma processing chamber 0107 is mostly protected by an inner cylinder such as quartz to prevent damage caused by plasma. In this example, a silicon substrate 0103 having a diameter of 300 mm is used as a substrate to be processed.

[0017] Prior art literature

[0018] Non-patent literature

[0019] Non-patent literature 1: Michael A. Lieberman and Allan J. Lichtenberg, Principles of plasma discharges and materials processing, Second Edition, Wiley-Interscience, First published 27 January 2005, John Wiley & Sons, Inc. Summary of the invention

[0020] Problems to be solved by the invention

[0021] use Figure 1When the plasma etching device 0100 shown in the figure performs etching and performs shape evaluation, depending on the processing conditions, sometimes an abnormal shape that becomes asymmetric in the inner and outer directions of the processed substrate 0103 can be seen on the outer periphery of the processed substrate 0103. The shape of plasma etching is a complex phenomenon in which various factors are intertwined with each other, and it is difficult to determine the cause. However, there is a possibility that the cause is the re-adhesion of the etching reaction product generated by the processed substrate 0103. In other words, there is a possibility that the density distribution of the reaction product on the processed substrate 0103 is uneven, and more re-adhesion occurs on one side.

[0022] The present disclosure provides a technique for preventing a plasma treatment defect near the outer periphery of a substrate to be treated. Other problems and novel features will become apparent from the description of this specification and the accompanying drawings.

[0023] Means for solving problems

[0024] The outline of the representative aspects of the present disclosure will be briefly described as follows.

[0025] According to one embodiment of the present disclosure, a technology (plasma processing device or etching processing method) having the following characteristics is provided, comprising: a processing chamber that performs plasma processing on a substrate to be processed; a high-frequency power supply that supplies microwave power via a waveguide; a dielectric plate that is arranged above the processing chamber and through which the microwaves pass; a sample stage that carries the substrate to be processed; an electromagnet that is arranged to surround the processing chamber and generate a first static magnetic field; a static magnetic field generating device that is arranged below the substrate to be processed; and a control device that controls the electromagnet, the static magnetic field generating device generating a second static magnetic field in a direction that enhances a static magnetic field parallel to a central axis of the processing chamber in the first static magnetic field, the control device controlling the electromagnet so that the angle of the magnetic field lines of a third static magnetic field relative to the processed surface of the substrate to be processed becomes a desired angle, the third static magnetic field being a static magnetic field in which the first static magnetic field and the second static magnetic field overlap.

[0026] Effects of the Invention

[0027] According to the present disclosure, it is possible to prevent a defect in plasma processing near the outer periphery of a substrate to be processed.

[0028] More specifically, the control device controls the multi-stage electromagnet to control the angle of the static magnetic field caused by the multi-stage electromagnet and the static magnetic field generating device relative to the surface of the processed surface of the processed substrate. Therefore, by utilizing the etching process of the plasma processing device or the plasma processing method involved in the present disclosure, the incident angle of the ions incident on the processed substrate can be controlled, thereby solving the above-mentioned problem. That is, since the ions are incident on the sheath end formed on the surface of the processed surface of the processed substrate along the magnetic force lines, the angle of the magnetic force lines near the periphery of the processed substrate relative to the surface of the processed surface of the processed substrate can be controlled to be, for example, approximately vertical (approximately 90°). Thus, near the periphery of the processed substrate, the incident angle of the ions can be controlled to improve shape abnormalities. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic side cross-sectional view of a microwave plasma etching device according to a comparative example.

[0030] Figure 2 It is a schematic side cross-sectional view of the microwave plasma etching device involved in the embodiment.

[0031] Figure 3 It is a schematic diagram of the magnetic field line distribution of the microwave plasma etching device involved in the embodiment.

[0032] Figure 4 It is an explanatory diagram of a control device according to an embodiment.

[0033] Figure 5 It is a graph showing the angle of magnetic field lines on the substrate to be processed.

[0034] Figure 6 It is a graph showing the ECR height and the radius of the substrate to be processed.

[0035] Figure 7 It is a graph showing the angle of the magnetic field lines on the substrate to be processed and the radius of the substrate to be processed. DETAILED DESCRIPTION

[0036] The following is an explanation of the embodiments using the accompanying drawings. In the following description, the same components are sometimes labeled with the same reference numerals, and repeated descriptions are omitted. In addition, in order to make the description clearer, the accompanying drawings are sometimes schematically expressed compared with the actual method, but this is only an example and does not limit the interpretation of the present invention.

[0037] use Figures 2 to 7 A microwave plasma etching device according to an embodiment will be described. Figure 21 is a schematic side cross-sectional view (longitudinal cross-sectional view) of a microwave plasma etching device according to an embodiment. The processed substrate 0210 is, for example, a disk-shaped single crystal silicon substrate with a diameter of 300 mm, and a semiconductor integrated circuit element is made on the processed substrate 0210. Figure 2 In the microwave plasma etching device (hereinafter also simply referred to as a plasma etching device or a plasma processing device) 0200 shown, plasma generated inside a roughly cylindrical processing chamber 0209 is used to perform plasma processing (here, etching processing) on ​​a structure formed by other processes on the surface of a processed substrate 0210 placed on a substrate electrode 0211 serving as a sample stage. The processed substrate 0210 is disc-shaped when viewed from the upper surface side, and requires plasma processing that is axisymmetric with respect to a central axis passing through the center point of the disc-shaped processed substrate 0210. Therefore, the plasma etching device 0200 also has a structure that is basically axisymmetric with respect to the central axis when viewed from the upper surface side. In addition, the substrate electrode 0211 is set to a circular shape when viewed from the upper surface side, and is set to a shape that is axisymmetric with respect to the central axis. Here, the center point of the disc-shaped processed substrate 0210 is symmetrical with respect to the central axis. Figure 3 The central axis passing through the center point (O) of the substrate 0210 to be processed corresponds to the central point O of the substrate 0210 to be processed. Figure 3 The axisymmetric relationship with respect to the central axis is referred to as the Z axis. Figure 3 The so-called axisymmetric structure refers to the Figure 3 The v-axis as the central axis can be replaced by the central axis of the plasma etching device 0200 or the central axis of the processing chamber 0209. In this case, the center point (O) of the processed substrate 0210 and the center point of the substrate electrode 0211 are arranged on the axis of the central axis.

[0038] The microwave generated from the microwave source 0230 as a radio frequency power supply is propagated to the circular waveguide 0201 via a microwave propagation device 0231 including an isolator, an automatic matching device, a rectangular waveguide, a circular polarization wave generator, etc. In other words, the microwave source 0230 supplies microwave power to the circular waveguide 0201. The circular waveguide 0201 is set to a cylindrical or circular tube shape, and the center of its cylindrical shape is arranged on the central axis (Z axis). That is, the center of the circular waveguide 0201 is coaxially arranged with the central axis of the processing chamber 0209. In addition, the microwave source 0230 is configured to supply microwave power to the processing chamber 0209 via the waveguide 0201.

[0039] The circularly polarized microwave passing through the circular waveguide 0201 is in the lowest order mode of the circular waveguide 0201, namely, TE 11The mode is transmitted to the cavity portion 0206. In this example, microwaves with a frequency of 2.45 GHz are used. In addition, the circular waveguide 0201 uses a circular waveguide with a diameter that can only propagate the lowest order mode.

[0040] The electromagnetic field of the microwave is shaped in the cavity 0206, and the shaped electromagnetic field is injected into the processing chamber 0209 via the microwave introduction window 0207 and the shower plate 0208. The microwave introduction window 0207 and the shower plate 0208 are arranged above the processing chamber 0209, and can be regarded as a dielectric plate that can transmit microwaves. The microwave introduction window 0207 can be regarded as a surface arranged on one side intersecting with the central axis of the processing chamber 0209. As the material of the microwave introduction window 0207 and the shower plate 0208, it is desirable to use a material, i.e., a dielectric, that has a small microwave loss, high plasma resistance, and does not have an adverse effect on the plasma treatment. In the present embodiment, quartz is used as the material of the microwave introduction window 0207 and the shower plate 0208. A gas used in the etching process is supplied from a gas supplier (not shown) into the processing chamber 0209 in a given amount through a small gap (not shown) between the microwave introduction window 0207 and the shower plate 0208 and a plurality of supply holes (not shown) provided in the shower plate 0208 .

[0041] Around the outer side (around the outer periphery) of the cylindrical processing chamber 0209, three levels of electromagnets 0203, 0204, and 0205 are provided. The multi-level electromagnets 0203, 0204, and 0205 can also be regarded as being coaxially (or axially symmetrically) arranged with the central axis so as to surround the processing chamber 0209. Furthermore, a yoke 0202 is provided around the outer sides of these electromagnets 0203, 0204, and 0205. The yoke 0202 is preferably made of a material with high magnetic permeability. In this example, an iron yoke is used. The electromagnets 0203, 0204, and 0205 are electrically connected to a control device 0250, and the control device 0250 is configured to control the driving current value of the electromagnets 0203, 0204, and 0205.

[0042] In this example, the first electromagnet 0203 as the upper electromagnet is arranged to surround the upper side portion of the outer side of the processing chamber 0209 except the setting portion of the circular waveguide 0201. The second electromagnet 0204 as the intermediate electromagnet is arranged to surround the upper side side portion of the outer side of the processing chamber 0209 below the first electromagnet 0203. In this example, the second electromagnet 0204 is arranged around the upper side side portion of the outer side of the processing chamber 0209 so as to surround the outer side of the cavity 0206 and the microwave introduction window 0207. The third electromagnet 0205 as the lower electromagnet is arranged to surround the side portion of the middle portion of the outer side of the processing chamber 0209 below the second electromagnet 0204. In this example, the third electromagnet 0205 is arranged around the side portion of the middle portion of the outer side of the processing chamber 0209 between the shower plate 0208 and the static magnetic field generating device 0212 described later.

[0043] In the present embodiment, as an example, three-stage electromagnets 0203, 0204, and 0205 are used. The number of electromagnets may be set to multiple levels such as 4 or 5 in accordance with the need to finely adjust the distribution of the static magnetic field. In addition, the number of electromagnets may be reduced to 2. In the present embodiment, the following divergent magnetic field is made by these electromagnets 0203, 0204, and 0205: the static magnetic field is strong in the area on the upper side of the processing chamber 0209 or the area on the side of the microwave input window 0207, and the static magnetic field is weak in the area on the lower side of the processing chamber 0209 (the area of ​​the processing chamber 0209 corresponding to the lower side of the shower plate 0208, or the area of ​​the processing chamber 0209 corresponding to the upper side of the substrate electrode 0211 described later). The structures of the electromagnets 0203, 0204, and 0205 are axisymmetric (axisymmetric relative to the Z axis) when viewed from the upper surface side, and the static magnetic fields generated by these electromagnets 0203, 0204, and 0205 are also axisymmetric when viewed from the upper surface side. Through this structure, the electron cyclotron resonance (ECR) condition, i.e., the ECR surface (ECR surface) of 875 Gauss, can be set in the processing chamber 0209, and the driving current value supplied to the electromagnets 0203, 0204, and 0205 can be adjusted by the control device 0250 to control the distance between the ECR surface and the processed surface of the processed substrate 0210 (also called ECR height (h)) and the shape of the ECR surface. Through the interaction between the microwaves and the static magnetic field, plasma can be generated in the processing chamber 0209. Here, the electron cyclotron resonance can be regarded as the electron cyclotron resonance caused by the interaction between the microwaves from the microwave source 0230 and the static magnetic field (also referred to as the first static magnetic field) generated by the electromagnets 0203 , 0204 , and 0205 .

[0044] A substrate 0210 to be processed and a substrate electrode 0211 having a placement surface for holding the substrate 0210 to be processed are arranged in the processing chamber 0209. The substrate electrode 0211 is arranged opposite to the microwave introduction window 0207 inside the processing chamber 0209, and is configured such that the substrate 0210 to be processed is arranged on the placement surface of the substrate electrode 0211 in a state where the center point of the substrate 0210 to be processed is coaxially arranged with the center axis.

[0045] The substrate electrode 0211 is built with a mechanism for electrostatically adsorbing and holding the substrate 0210 to be processed, a mechanism for temperature control of the substrate 0210 to be processed, and a mechanism for supplying RF (Radio frequency) bias to the substrate 0210 to be processed. A vacuum exhaust device 0214 is provided in the processing chamber 0209 via an exhaust speed adjustment mechanism 0213. A given gas is supplied to the processing chamber 0209 at a given pressure and a given flow rate through the exhaust speed adjustment mechanism 0213, the vacuum exhaust device 0214, and a gas supply mechanism (not shown). Since the etching process is also affected by the flow of gas in the processing chamber 0209, the structure of the gas flow (for example, the configuration positions of the multiple supply holes provided in the shower plate 0208) is also axisymmetric so as to be axisymmetric when observed from the upper surface side.

[0046] A static magnetic field generating device 0212 as a static magnetic field generating source is provided on the back side of the substrate electrode 0211 opposite to the mounting surface of the substrate electrode 0211. In this example, the static magnetic field generating device 0212 is built into the substrate electrode 0211. In addition, in a state where the processed substrate 0210 is mounted on the mounting surface of the substrate electrode 0211, the static magnetic field generating device 0212 can also be said to be arranged on the back side of the processed substrate 0210 relative to the processed surface of the processed substrate 0210. Alternatively, the static magnetic field generating device 0212 can also be said to be arranged below the processed substrate 0210.

[0047] The static magnetic field on the surface of the processed surface of the processed substrate 0210 is set to be a static magnetic field (also called a third static magnetic field) in which the first static magnetic field generated by the electromagnets 0203, 0204, and 0205 and the second static magnetic field generated by the static magnetic field generating device 0212 overlap (synthesize). The static magnetic field generating device 0212 is set to be a structure that generates the second static magnetic field in the direction of enhancing the static magnetic field parallel to the central axis of the processing chamber 0209 in the first static magnetic field. The static magnetic field generating device 0212 can control the angle of the static magnetic field (third static magnetic field) to be perpendicular (90 degrees) or approximately perpendicular (approximately 90 degrees) to the surface of the processed surface of the processed substrate 0210. As the static magnetic field generating device 0212, an electromagnet or a permanent magnet can be used. In this embodiment, a structural example using a permanent magnet as the static magnetic field generating device 0212 is described. If an electromagnet is used as the static magnetic field generating device 0212, there is an advantage that the size and distribution of the static magnetic field can be easily controlled by adjusting the driving current. However, in this case, a cooling mechanism, a current supply mechanism, etc. are required, which is sometimes not conducive to the miniaturization of the static magnetic field generating device 0212. In addition, the static magnetic field generating device 0212 is preferably arranged near the surface of the substrate 0210 to be processed. If the static magnetic field generating device 0212 is arranged at a position far from the surface of the substrate 0210 to be processed, the static magnetic field generated by the static magnetic field generating device 0212 needs to be a strong static magnetic field. Therefore, this is because the miniaturization of the static magnetic field generating device 0212 is further difficult. Since the exhaust performance is reduced if a large electromagnet is located in the vacuum exhaust path, in this embodiment, the static magnetic field generating device 0212 using a permanent magnet that can be miniaturized is arranged near the substrate 0210 to be processed. Specifically, the static magnetic field generating device 0212 using a permanent magnet is provided on the back side of the substrate electrode 0211 that is opposite to the loading surface of the substrate 0210 to be processed. The static magnetic field generating device 0212 using a permanent magnet has a circular shape when viewed from the upper surface side. Similarly, the substrate electrode 0211 also has a circular shape when viewed from the upper surface side.

[0048] Figure 3 Schematic diagram of the magnetic field line distribution of the microwave plasma etching device involved in the embodiment. Figure 3 , the arrangement of the circular waveguide 0201, the substrate to be processed 0210, the substrate electrode 0211, and the static magnetic field generating device 0212 when viewed from the upper surface side, and the relationship between the origin O, the z-axis, and the r-axis described later are shown. In addition, the short control line indicated by the dotted arrow output from the control device 0250 is originally connected to Figure 2 Similarly connected to electromagnets 0203, 0204, 0205, but in order to Figure 3 The simplification is shown by short control lines.

[0049] exist Figure 3 The schematic diagram shows the magnetic field lines (also called first magnetic field lines) 0301 generated only by the electromagnets 0203, 0204, and 0205, and the magnetic field lines (also called second magnetic field lines) 0302 generated only by the static magnetic field generating device 0212. In fact, the static magnetic fields generated by the magnetic field lines 0301 and 0302 overlap, but Figure 3 In order to facilitate the explanation of the operation, the magnetic lines 0301 and 0302 are shown when the other side does not exist. Figure 3 In the figure, when observed from the upper surface side, the central axis of the surface of the processed surface of the disk-shaped processed substrate 0210 is taken as the origin O, the z-axis is shown in the longitudinal direction, and the r-axis is shown in the radial direction. The magnetic lines of force 0301 of the electromagnets 0203, 0204, and 0205 are downward on the z-axis, and the magnetic lines of force 0302 of the static magnetic field generating device 0212 are also downward on the z-axis, generating a static magnetic field in a direction that enhances each other. That is, the static magnetic field generating device 0212 generates a static magnetic field that enhances the direction of the magnetic lines of force 0302 of the static magnetic field parallel to the central axis in the static magnetic field of the magnetic lines of force 0301 generated by the multi-stage electromagnets 0203, 0204, and 0205. Conversely, a static magnetic field in which both are upward can also be used. On the other hand, it can be seen that if the r-axis component is viewed from the surface of the substrate 0210 to be processed (on the r-axis), the magnetic force lines 0301 generated by the electromagnets 0203, 0204, and 0205 are directed outward, and the magnetic force lines 0302 generated by the static magnetic field generating device 0212 are directed inward, and the r-direction components of the static magnetic field are mutually offset (weakened) by the overlap of the two. Figure 3 In the structure shown, near the surface of the substrate 0210 to be processed, the static magnetic field is adjusted to a more vertical direction relative to the surface of the substrate 0210 to be processed by the static magnetic field generating device 0212. Figure 3 , the three-stage structure of electromagnets 0203, 0204, and 0205 is described, but it is clear that the same effect of verticalizing the static magnetic field can also be obtained in structures with other electromagnets. Among them, when the number of electromagnets is small, the number of parameters for adjustment is small, so as described later, the degree of freedom of adjustment is sometimes reduced. In order to adjust the parameters such as the height of the ECR surface while verticalizing the static magnetic field on the processed substrate 0210 described later, it is preferred to set electromagnets (0203, 0204, 0205) with more than two stages.

[0050] like Figure 3As shown, when viewed from the upper surface side, the centers of the circular waveguide 0201, the substrate electrode 0211, the processed substrate 0210, the substrate electrode 0211, and the static magnetic field generating device 0212 are arranged coaxially with the origin O which is the center axis of the surface of the processed surface of the disc-shaped processed substrate 0210, and are arranged to be axisymmetric with respect to the z-axis passing through the origin O. With regard to the sizes of the substrate electrode 0211, the processed substrate 0210, the substrate electrode 0211, and the static magnetic field generating device 0212 when viewed from the upper surface side, in this example, the disc-shaped (or circular) substrate electrode 0211 is the largest, followed by the disc-shaped (or circular) static magnetic field generating device 0212 using a permanent magnet, and the disc-shaped (or circular) processed substrate 0210 is the third largest. Thus, the angle of the third static magnetic field obtained by synthesizing the first static magnetic field of the electromagnets 0203, 0204, and 0205 and the second static magnetic field generating device 0212 at the periphery of the processed surface of the processed substrate 0210 can be controlled to be perpendicular (90 degrees) or approximately perpendicular (approximately 90 degrees) to the surface of the processed surface of the processed substrate 0210.

[0051] pass Figure 4 The operation of the control device 0250 that controls the electromagnets 0203, 0204, and 0205 will be described below. Figure 4 is an explanatory diagram of a control device according to an embodiment of the present invention. Figure 2 , 3 The control device 0250 includes the current control device 400 and a plurality of current sources CS1, CS2, and CS3. In this example, the plurality of current sources CS1, CS2, and CS3 correspond to the three-stage electromagnets 0203, 0204, and 0205, and an example of three current sources CS1, CS2, and CS3 is shown.

[0052] The current control device 400 has a function of obtaining the driving current of the electromagnets 0203, 0204, 0205 so that the angle of the static magnetic field in the surface of the processed surface of the processed substrate 0210 is perpendicular to the surface of the processed surface while satisfying the input static magnetic field specification 401. The static magnetic field specification 401 is input to the current control device 400, and the current control device 400 obtains the current control signals S1, S2, S3 according to the static magnetic field specification 401 and sends them to the current sources CS1, CS2, CS3. The current sources CS1, CS2, CS3 supply the driving currents I1, I2, I3 to the electromagnets 0203, 0204, 0205 respectively in accordance with the current control signals S1, S2, S3. Thus, the current control device 400 can control the magnetic field lines 0301 generated from the multi-stage electromagnets 0203, 0204, 0205 and the static magnetic field based thereon. Figure 4The case where the electromagnets 0203, 0204, and 0205 are three-stage is described, but the same is true for other stages.

[0053] In the present embodiment, the static magnetic field specification 401 is set as the specification of the static magnetic field determined by the distance between the ECR surface on the central axis (z-axis) of the microwave plasma etching device 0200 and the surface of the processed surface of the processed substrate 0210 (hereinafter referred to as the ECR height (h)) as a parameter. As mentioned above, this is because the ECR surface is an important parameter that affects the characteristics of plasma processing. The static magnetic field specification 401 can also be other items or multiple items, but the number of items of the specification that can be set is limited by the number of levels of the electromagnet (0203, 0204, 0205). For example, in the case of using a 1-level electromagnet, if the static magnetic field near the surface of the processed surface of the processed substrate 0210 is controlled to be perpendicular to the surface of the processed surface of the processed substrate 0210, the current value supplied to the electromagnet is uniquely determined, and there is no room for adjusting the static magnetic field specification 401 such as the ECR height. In principle, a maximum of one static magnetic field specification 401 can be satisfied in a 2-stage electromagnet, and a maximum of two static magnetic field specifications 401 can be satisfied in a 3-stage electromagnet. The same is true for electromagnets of 4 or higher stages. It goes without saying that, for example, the static magnetic field specification 401 can be reduced to one item in a 3-stage electromagnet to provide redundancy.

[0054] In general, when there are multiple static magnetic field generating sources (0212), the overall static magnetic field becomes a superposition of the static magnetic fields when each static magnetic field generating source (0212) is separately present. In the storage device in the current control device 400, the first distribution data in the processing chamber 0209 of the static magnetic flux density generated by the permanent magnet (0212) monomer and the second distribution data in the processing chamber 0209 of the static magnetic flux density generated by the multi-stage electromagnet (0203, 0204, 0205) monomer driven by a given current are stored as reference data. These first distribution data and the second distribution data can be used to obtain the static magnetic flux density at any coordinate (r, z) in the processing chamber 0209 by linear superposition using the following formula 2.

[0055]

Mathematical formula 1

[0056] Number 1

[0057]

[0058] B r (r, z): I flows through all electromagnets i (i = 1, 2, 3). i The r-direction component of the magnetic flux density at the coordinate (r, z) in the processing chamber of the case (A) (here, electromagnet 1 corresponds to electromagnet 0203, electromagnet 2 corresponds to electromagnet 0204, and electromagnet 3 corresponds to electromagnet 0205)

[0059] B z (r, z): I flows through all electromagnets i (i = 1, 2, 3). i The z-direction component of the magnetic flux density at the coordinate (r, z) in the processing chamber in case (A)

[0060] B ir (r, z): A given current I flows only through the electromagnet i (i=1, 2, 3) at the coordinate (r, z) in the processing chamber. 0i (A) The r-direction component of the magnetic flux density

[0061] B iz (r, z): A given current 1 flows only through the electromagnet i (i=1, 2, 3) at the coordinate (r, z) in the processing chamber. 0i The z-direction component of the magnetic flux density in case (A)

[0062] B mr (r, z): The r-direction component of the magnetic flux density of the permanent magnet at the coordinate (r, z) in the processing chamber only

[0063] B mz (r, z): z-direction component of the magnetic flux density of the permanent magnet at the coordinate (r, z) in the processing chamber only

[0064] In this embodiment, B is obtained in advance by theoretical calculation based on the finite element method. ir , B iz (i=1、2、3)、B mr , B mz Alternatively, a value actually measured using a magnetic sensor may be used, or a value may be obtained by theoretical calculation at any time.

[0065] For example, if we want to control the r component of the magnetic flux density at a certain point (r0, z0) to a specific value B 0r In the case of i (i = 1, 2, 3) have a linear function relationship. For example, if currents I1 and I2 are assigned to the range of electromagnets 0203 and 0204 to obtain current I3, and if this value is the range of electromagnet 0205, the magnetic flux density distribution can be further obtained using equation 2. From the obtained magnetic flux density distribution, a combination of currents I1, I2, and I3 that meets the desired specifications can be searched.

[0066] In the above, the case where the number of stages of the electromagnets is three has been described, but the same is true even if the number of stages is other than three.

[0067] In the present embodiment, it is desirable to control the angle of the magnetic force lines on the surface of the processed surface of the processed substrate 0210 to be perpendicular (or approximately perpendicular) to the surface of the processed surface of the processed substrate 0210. Furthermore, since a divergent magnetic field is used, there is a tendency for the deviation of the magnetic force lines from the perpendicular to become larger as the distance from the center point O of the processed substrate 0210 increases. In addition, by setting the r component of the magnetic flux density to zero, the angle of the magnetic force lines can be made perpendicular to the surface of the processed surface of the processed substrate 0210. Based on the above, the r component of the magnetic flux density at the outermost peripheral position of the processed substrate 0210 is controlled to zero.

[0068] Figure 5 It is a graph showing the angle of magnetic field lines on the substrate being processed. Figure 5 To illustrate an example of controlling the angle of the magnetic field lines on the processed substrate 0210 to be vertical. Figure 5 In the graph, the vertical axis represents the angle θ (°) of the magnetic flux density vector on the processed substrate 0210 relative to the surface of the processed substrate 0210. The horizontal axis represents the radius r (mm) on the processed substrate. In the graph, the case where a permanent magnet is configured as the static magnetic field generating device 0212 (with a permanent magnet: represented by line L1) and the case where it is not configured (without a permanent magnet: represented by line L2) are compared. The permanent magnet is used for adjustment so that the magnetic field lines become vertical (90°) at a position of 150 mm radius of the outermost circumference of the processed substrate 0210 with a diameter of 300 mm. It can be seen that by using a permanent magnet, it can be vertical to approximately the entire surface of the processed substrate 0210 (radius r is within the range of 0 mm to 150 mm).

[0069] Figure 6 is a graph showing the ECR height and the radius of the substrate being processed. Figure 7 is a graph showing the angle of the magnetic field lines on the substrate being processed and the radius of the substrate being processed. Figure 6 and Figure 7 , the results are shown when the ECR height (h (mm)) is controlled to 150 mm, 170 mm, 185 mm, and 200 mm. Figure 6 represents the ECR height (h (mm)) at each radius (r (mm)), Figure 7 represents the angle θ (°) of the magnetic field lines on the substrate 0210 being processed. Figure 7 In FIG. 1 , since graphs with different current values ​​almost overlap, the line becomes one.

[0070] exist Figure 6, line L21 is the case where the ECR height (h (mm)) is adjusted to 150mm, and the driving current values ​​(ampere: A) of the electromagnets 0203, 0204, and 0205 are set to 27A, 12A, and 17A. Line L22 is the case where the ECR height (h (mm)) is adjusted to 170mm, and the driving current values ​​(A) of the electromagnets 0203, 0204, and 0205 are set to 27A, 26A, and 14A. Line L23 is the case where the ECR height (h (mm)) is adjusted to 185mm, and the driving current values ​​(A) of the electromagnets 0203, 0204, and 0205 are set to 27A, 26A, and 10A. Line L24 is the case where the ECR height (h (mm)) is adjusted to 200mm, and the driving current values ​​of the electromagnets 0203, 0204, and 0205 are set to 27A, 30A, and 4A.

[0071] exist Figure 7 In the figure, line L31 is the same as line L21, when the ECR height (h (mm)) is adjusted to 150 mm, and the driving current values ​​(A) of the electromagnets 0203, 0204, and 0205 are set to 27 A, 12 A, and 17 A. Line L32 is the same as line L22, when the ECR height (h (mm)) is adjusted to 170 mm, and the driving current values ​​(A) of the electromagnets 0203, 0204, and 0205 are set to 27 A, 26 A, and 14 A. Line L33 is the same as line L23, when the ECR height (h (mm)) is adjusted to 185 mm, and the driving current values ​​(A) of the electromagnets 0203, 0204, and 0205 are set to 27 A, 26 A, and 10 A. Line L34 is the same as line L24 when the ECR height (h (mm)) is adjusted to 200 mm, and the driving current values ​​(A) of the electromagnets 0203, 0204, and 0205 are set to 27 A, 30 A, and 4 A.

[0072] Therefore, if Figure 6 and Figure 7 As can be seen, when the diameter of the substrate 0210 to be processed is 300 mm, when the radius r of the substrate 0210 to be processed is within 0 mm to 150 mm, and the angle θ (°) of the magnetic field line is substantially vertical (90°), the ECR height h can be adjusted to a desired height of 150 mm to 200 mm. The diameter of the substrate 0210 to be processed is not limited to 300 mm, and may be smaller or larger than 300 mm.

[0073] Thus, it is possible to prevent the plasma treatment from being bad near the periphery of the substrate 0210 to be processed. That is, the shape of the plasma treatment near the center of the substrate 0210 to be processed and the shape of the plasma treatment near the periphery of the substrate 0210 to be processed can be made the same. Furthermore, the shape of the plasma treatment from the vicinity of the center of the substrate 0210 to the vicinity of the periphery of the substrate 0210 to be processed can be made the same. Therefore, the quality of the plasma treatment can be made uniform over the entire processed surface of the substrate 0210 to be processed.

[0074] In addition, since the distance between the ECR surface and the processed surface of the processed substrate can be adjusted, the ratio and density of ions and free radicals on the processed surface of the processed substrate 0210 can be adjusted, and the quality of plasma processing such as the plasma processing shape can be optimized.

[0075] Here, as shown in (A) to (C) below, the current control device 400 controls the drive current values ​​I1, I2, and I3 supplied to the electromagnets 0203, 0204, and 0205 of the plurality of stages.

[0076] (A) The current control device 400 controls the driving current values ​​I1, I2, and I3 supplied to the multi-stage electromagnets 0203, 0204, and 0205 to control the angle of the static magnetic field (third static magnetic field) based on the magnetic field lines (first static magnetic field) synthesized (overlapped) by the static magnetic field lines 0301 generated by the multi-stage electromagnets 0203, 0204, and 0205 and the static magnetic field (second static magnetic field) based on the magnetic field lines 0302 generated by the static magnetic field generating device 0212 relative to the surface of the processed surface of the processed substrate. In other words, the current control device 400 is configured to control the electromagnets (0203, 0204, and 0205) so that the angle of the magnetic field lines of the third static magnetic field relative to the processed surface of the processed substrate 0210 becomes a desired angle.

[0077] (B) In addition, the current control device 400 controls the driving current values ​​of the multi-stage electromagnets 0203, 0204, and 0205 so that 1) at the peripheral portion of the processed surface of the processed substrate 0210, the angle of the third static magnetic field relative to the surface of the processed surface becomes approximately vertical (approximately 90 degrees), and 2) the height between the ECR surface and the surface of the processed surface of the processed substrate 0210 becomes the desired height.

[0078] (C) In addition, the current control device 400 controls the driving current values ​​of the multi-stage electromagnets 0203, 0204, and 0205 so that the angle of the third static magnetic field relative to the surface of the processed surface becomes approximately vertical (approximately 90 degrees) over the entire area of ​​the processed surface of the processed substrate 0210.

[0079] The plasma processing method using the plasma etching apparatus 0200 according to the present embodiment includes the following steps S1, S2, S3, and S4.

[0080] (Step S1) A substrate carrying step of placing the substrate to be processed 0210 on the placing surface of the substrate electrode 0211 in the processing chamber 0209.

[0081] (Step S2 ) A plasma generating step of generating plasma in the processing chamber 0209 .

[0082] (Step S3) A plasma processing step of supplying gas into the processing chamber 0209 to perform plasma processing.

[0083] (Step S4) After the plasma processing step is completed, a substrate unloading step is performed in which the processed substrate 0210 is carried out of the processing chamber 0209.

[0084] In step S2 , the multi-pole electromagnets 0203 , 0204 , and 0205 are controlled by the current control device 400 to generate a first static magnetic field based on the first magnetic force lines 0301 .

[0085] In step S2, as described above, as shown in (A) to (C), the current control device 400 controls the driving current values ​​I1, I2, and I3 supplied to the multi-stage electromagnets 0203, 0204, and 0205. That is, step S2 includes: a first step of controlling the multi-stage electromagnets 0203, 0204, and 0205 so that the angle of the magnetic force lines of the third static magnetic field relative to the processed surface of the processed substrate 0210 becomes a desired angle. Furthermore, step S2 includes: a second step of controlling the multi-stage electromagnets 0203, 0204, and 0205 so that the height from the processed surface of the processed substrate 0210 to the electron cyclotron resonance surface becomes a desired height. Here, the first step is set as a step of controlling the multi-stage electromagnets 0203, 0204, and 0205 so that the angle of the magnetic force lines of the third static magnetic field relative to the outer periphery of the processed surface of the processed substrate 0210 becomes approximately 90 degrees. In addition, the first step is a step of controlling the multi-stage electromagnets 0203, 0204, and 0205 so that the angle of the magnetic field lines of the third static magnetic field in the entire area of ​​the processed surface of the processed substrate 0210 becomes approximately 90 degrees. In addition, the plasma generation step (step S2) and the plasma processing step (step S3) are sometimes defined as one step.

[0086] Therefore, since the incident angle of ions incident on the processed substrate 0210 can be controlled by etching processing using the plasma processing device 0200 or the plasma processing method involved in the present disclosure, the above-mentioned problem can be solved. Since the ions are incident on the sheath end formed on the surface of the processed surface of the processed substrate 0210 along the magnetic force lines, the angle of the magnetic force lines near the outer periphery of the processed substrate 0210 relative to the surface of the processed surface of the processed substrate 0210 can be controlled to be, for example, approximately vertical (90°). Thus, the shape abnormality in plasma processing can be improved by controlling the incident angle of ions near the outer periphery of the processed substrate 0210, and the quality of plasma processing such as the plasma processing shape can be improved.

[0087] The above describes the case where the magnetic field lines on the processed substrate 0201 are controlled to be perpendicular to the surface of the processed substrate, but they can also be controlled to a given angle. That is, as a static magnetic field specification, in addition to the ECR height, the angle of the magnetic field lines relative to the surface of the processed substrate can also be added to the specification. The asymmetric shape at the periphery of the processed substrate seen in the plasma etching device of the comparative example can be improved by controlling the incident angle of the ions.

[0088] As mentioned above, the disclosure made by the present inventor has been specifically described based on the embodiments, but it is needless to say that the present disclosure is not limited to the above-mentioned embodiments and that various modifications are possible.

[0089] Description of Reference Numerals

[0090] 0101: circular waveguide, 0102: electromagnet, 0103: substrate to be processed, 0104: cavity, 0105: microwave introduction window, 0106: shower plate, 0107: plasma processing chamber, 0201: circular waveguide, 0202: yoke, 0203: electromagnet, 0204: electromagnet, 0205: electromagnet, 0206: cavity, 0207: microwave introduction window, 0208: shower plate, 0209: processing chamber, 0210: substrate to be processed, 0211: substrate electrode, 0212: static magnetic field generating device, 0213: exhaust speed adjusting mechanism, 0214: vacuum exhaust device, 0250: control device, 0301: magnetic field lines (first magnetic field lines), 0302: magnetic field lines (second magnetic field lines), 400: current control device, 401: static magnetic field specifications.

Claims

1. A plasma processing device, characterized in that: have: a processing chamber for performing plasma processing on a substrate to be processed; a high frequency power source that supplies microwave power via a waveguide; a dielectric plate disposed above the processing chamber and through which the microwaves pass; A sample stage, on which the processed substrate is placed; An electromagnet, which is arranged to surround the processing chamber and generate a first static magnetic field; A static magnetic field generating device, which is arranged below the substrate to be processed; and a control device, which controls the electromagnet, The static magnetic field generating device generates a second static magnetic field in the first static magnetic field in a direction to enhance the static magnetic field parallel to the central axis of the processing chamber. The control device controls the electromagnet so that the angle of the magnetic field lines of the third static magnetic field relative to the processed surface of the processed substrate becomes a desired angle. The third static magnetic field is a static magnetic field in which the first static magnetic field and the second static magnetic field overlap.

2. The plasma processing device according to claim 1, characterized in that: The static magnetic field generating device is a permanent magnet.

3. The plasma processing device according to claim 2, characterized in that: The desired angle is approximately 90 degrees.

4. The plasma processing device according to claim 2, characterized in that: The control device controls the electromagnet so that the angle of the outer peripheral portion of the processed surface becomes approximately 90 degrees and the height from the processed surface to the electron cyclotron resonance surface becomes a desired height. The electron cyclotron resonance is electron cyclotron resonance caused by the interaction between the microwave and the first static magnetic field.

5. The plasma processing device according to claim 4, characterized in that: The control device controls the electromagnet so that the angle in the entire area of ​​the processed surface becomes substantially 90 degrees.

6. A plasma treatment method, characterized in that: It is a plasma processing method using a plasma processing device. The plasma processing device comprises: a processing chamber for performing plasma processing on a substrate to be processed; a high frequency power source that supplies microwave power via a waveguide; a dielectric plate disposed above the processing chamber and through which the microwaves pass; A sample stage, on which the processed substrate is placed; An electromagnet, which is arranged to surround the processing chamber and generate a first static magnetic field; and a static magnetic field generating device configured to generate a second static magnetic field in the first static magnetic field in a direction to enhance the static magnetic field parallel to the central axis of the processing chamber, and arranged below the substrate to be processed, The plasma processing method comprises: a first step of controlling the electromagnet so that the angle of the magnetic field lines of the third static magnetic field relative to the processing surface of the processing substrate becomes a desired angle, The third static magnetic field is a static magnetic field in which the first static magnetic field and the second static magnetic field overlap.

7. The plasma processing method according to claim 6, characterized in that: The desired angle is approximately 90 degrees.

8. The plasma processing method according to claim 6, characterized in that: The plasma processing method further comprises: a second step of controlling the electromagnet so that the height from the processed surface to the electron cyclotron resonance surface becomes a desired height, The first step is a step of controlling the electromagnet so that the angle of the outer peripheral portion of the processed surface becomes approximately 90 degrees. The electron cyclotron resonance is electron cyclotron resonance caused by the interaction between the microwave and the first static magnetic field.

9. The plasma processing method according to claim 8, characterized in that: The first step is a step of controlling the electromagnet so that the angle in the entire area of ​​the processed surface becomes substantially 90 degrees.

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