JP5934030B2 - Plasma processing apparatus, plasma generation apparatus, antenna structure, and plasma generation method - Google Patents

Description

  The present invention relates to a plasma processing apparatus, a plasma generation apparatus, an antenna structure, and a plasma generation method for generating plasma using an ICP (Inductive Coupling Plasma) antenna.

  In a plasma processing apparatus including a chamber and an ICP (Inductive Coupling Plasma) antenna disposed outside the chamber, the ceiling portion of the chamber facing the ICP antenna is configured by a dielectric material, for example, a dielectric window made of quartz. . In this plasma processing apparatus, a high-frequency current flows through an ICP antenna connected to a high-frequency power source, and the high-frequency current generates lines of magnetic force in the ICP antenna. The generated magnetic field lines pass through the dielectric window and generate a magnetic field along the ICP antenna in the chamber. When the magnetic field changes with time, an induced electric field is generated, and electrons accelerated by the induced electric field collide with molecules or atoms of the processing gas introduced into the chamber to generate plasma. Since the induction electric field is generated along the ICP antenna, plasma is also generated along the ICP antenna in the chamber.

  Since the dielectric window partitions the inside of the chamber, which is a reduced pressure environment, from the outside of the chamber, which is an atmospheric pressure environment, the dielectric window needs to have a thickness that can secure rigidity capable of withstanding the pressure difference. Further, since it is expected that the size of a substrate housed in a chamber and subjected to plasma processing, for example, an FPD (Flat Panel Display) will continue to increase in the future, the diameter of the dielectric window facing the substrate is increased. Since it is necessary to ensure rigidity when the diameter is increased, it is necessary to further increase the thickness of the dielectric window.

  However, as the dielectric window becomes thicker, the weight of the dielectric window increases and the cost also rises. Therefore, the ceiling of the chamber is made of a highly rigid and inexpensive conductor such as a conductor window made of metal. It has been proposed to do. Since the metal shields the magnetic field lines in the conductor window, a slit penetrating the conductor window is provided, and the magnetic field lines are transmitted through the slit. However, since the number and size of slits to be provided are limited, the transmission efficiency of magnetic lines of force is reduced in the conductor window, and as a result, plasma generation efficiency is reduced in the chamber.

  On the other hand, it has been proposed to provide a floating coil with a capacitor outside the chamber and in the vicinity of the ICP antenna (see, for example, Patent Document 1). In this floating coil, an induced current flows due to electromagnetic induction by magnetic lines generated by the ICP antenna. The induced current generates magnetic lines in the floating coil, and the generated magnetic lines pass through the dielectric window and follow the floating coil in the chamber. To generate a magnetic field. That is, in the chamber, not only the magnetic field along the ICP antenna but also the magnetic field along the floating coil is generated, so that the floating coil serves as an auxiliary antenna, and the induced electric field generated in the chamber becomes strong, resulting in the generation of plasma. A decrease in efficiency can be prevented.

JP2011-119659A

  Even in the ICP antenna facing the conductor window, it is conceivable to reinforce the induction electric field by applying the technique of the above-mentioned Patent Document 1, but it is necessary to provide a floating coil in addition to the ICP antenna. There is a problem that becomes complicated.

  An object of the present invention is to provide a plasma processing apparatus, a plasma generation apparatus, an antenna structure, and a plasma generation method capable of simplifying the configuration of the apparatus and preventing a decrease in plasma generation efficiency.

In order to achieve the above object, a plasma processing apparatus of the present invention includes a processing chamber that accommodates a substrate, a mounting table that is disposed inside the processing chamber and mounts the substrate, and a front surface outside the processing chamber. In a plasma processing apparatus comprising an inductively coupled antenna disposed to face a mounting table and connected to a high-frequency power source, a wall portion of the processing chamber facing the inductively coupled antenna is formed, and the mounting table and the induction Further comprising a window member made of a conductor interposed between the coupling antennas, the window member is divided into a plurality of divided pieces, the plurality of divided pieces are not in direct contact with each other so as not to be electrically connected to each other, at least some of the divided pieces are connected by a wire to form a closed circuit, said closed circuit, have at least one capacitor in said wire to connect each of the divided pieces, Li said closed circuit Inductance capacitance of the capacitor so that the negative and said Rukoto adjusted.

In order to achieve the above object, a plasma generation apparatus of the present invention is a plasma generation apparatus for generating plasma in a decompression chamber, the inductively coupled antenna being disposed outside the decompression chamber and connected to a high frequency power source, A window member made of a conductor interposed between the inductively coupled antenna and the plasma in the decompression chamber, the window member being divided into a plurality of divided pieces, and the plurality of divided pieces are not electrically connected to each other. in not in direct contact manner, at least some of the divided piece is connected by wires to form a closed circuit, said closed circuit, have at least one capacitor in said wire to connect each of the divided pieces, the the capacitance of the capacitor as the reactance of the closed circuit is negative and said Rukoto adjusted.

In order to achieve the above object, an antenna structure of the present invention includes an inductively coupled antenna connected to a high frequency power source, and is interposed between the inductively coupled antenna and the plasma generated by the inductively coupled antenna. A window member made of a conductor, wherein the window member is divided into a plurality of divided pieces, the plurality of divided pieces are not in direct contact with each other so that they are not electrically connected to each other, and at least some of the divided pieces are are connected by a wire to form a closed circuit, said closed circuit, have at least one capacitor in said wire to connect each of the divided pieces, electrostatic of the capacitor as a reactance of the closed circuit is negative capacity is characterized Rukoto adjusted.

In order to achieve the above object, a plasma generation method of the present invention includes an inductively coupled antenna connected to a high frequency power source, and a window member made of a conductor interposed between the inductively coupled antenna and the plasma, The window member is divided into a plurality of divided pieces, and the plurality of divided pieces is a plasma generation method using an antenna structure that is insulated from each other, and has at least some of the divided pieces and at least one capacitor. A closed circuit is formed by connecting with conducting wires, and the capacitance of the capacitor is adjusted so that the reactance of the closed circuit becomes negative.

  According to the present invention, the window member made of a conductor facing the inductively coupled antenna connected to the high frequency power source is divided into a plurality of divided pieces, and at least some of the divided pieces are connected by the conductive wires to form a closed circuit. Since the closed circuit has at least one capacitor in the conductor connecting each segment, the closed circuit has a capacitor and faces the inductively coupled antenna. As a result, the magnetic field generated from the inductively coupled antenna generates an induced current in the closed circuit by electromagnetic induction, the induced current generates a magnetic field in the closed circuit, and the magnetic field generated in the closed circuit generates an induced electric field. As a result, plasma is generated, so that by changing the capacitance of the capacitor and adjusting the reactance of the closed circuit to control the induced current generated in the closed circuit, the plasma can be generated without adding a new auxiliary antenna. A decrease in efficiency can be prevented. That is, the configuration of the apparatus can be simplified, and a decrease in plasma generation efficiency can be prevented.

It is sectional drawing which shows schematically the structure of the plasma processing apparatus which concerns on embodiment of this invention. FIG. 2 is a plan view when the window member and the ICP antenna in FIG. 1 are viewed along a hollow arrow in FIG. 1. It is a figure for demonstrating the induced current produced | generated by the closed circuit in FIG. It is a graph which shows the relationship between the electrostatic capacitance of a conducting wire capacitor, and an induction current. It is a top view which shows the 1st modification of the window member in FIG. It is a top view which shows the 2nd modification of the window member in FIG. It is a top view which shows the 3rd modification of the window member in FIG. It is a top view which shows the 4th modification of the window member in FIG. It is a top view which shows the 5th modification of the window member in FIG. It is a top view which shows the 6th modification of the window member in FIG. It is a top view which shows the 7th modification of the window member in FIG. It is a top view which shows the 8th modification of the window member in FIG. It is a top view which shows the 9th modification of the window member in FIG. It is a top view which shows the 10th modification of the window member in FIG. It is a top view which shows the 1st modification of the window member in FIG. It is a top view which shows the 1st modification of the window member in FIG. It is a top view which shows the 13th modification of the window member in FIG. It is a top view which shows the 14th modification of the window member in FIG. It is a top view which shows the 15th modification of the window member in FIG. It is a top view which shows the 16th modification of the window member in FIG. It is a top view which shows the 17th modification of the window member in FIG. It is sectional drawing which shows schematically the structure of the plasma production apparatus which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, a plasma processing apparatus according to an embodiment of the present invention will be described.

  FIG. 1 is a cross-sectional view schematically showing a configuration of a plasma processing apparatus according to an embodiment of the present invention.

  In FIG. 1, a plasma processing apparatus 10 is disposed, for example, at a chamber 11 (processing chamber, decompression chamber) that houses a glass substrate (hereinafter simply referred to as “substrate”) S for FPD, and at the bottom of the chamber 11. A mounting table 12 for mounting the substrate S on the upper surface, an ICP antenna 13 (inductive coupling antenna) disposed outside the chamber 11 so as to face the mounting table 12 inside the chamber 11, and a ceiling portion of the chamber 11 And a window member 14 interposed between the mounting table 12 and the ICP antenna 13.

  The chamber 11 has a substantially casing shape, and is sized to accommodate a 10th generation substrate S having a size of 2880 mm × 3130 mm, for example. The chamber 11 has an exhaust device 15, and the exhaust device 15 evacuates the chamber 11 to make the inside of the chamber 11 a reduced pressure environment. On the other hand, the outside of the chamber 11 is an atmospheric pressure environment, and the window member 14 partitions the inside of the chamber 11 from the outside. The window member 14 is made of a conductor, for example, a metal such as aluminum, or a semiconductor, for example, silicon. The window member 14 is composed of a plurality of divided pieces, and has a size capable of covering at least the entire surface of the substrate S placed on the mounting table 12 as a whole.

  The mounting table 12 is made of a conductive member, and includes a rectangular parallelepiped susceptor 16 that functions as a base, and an electrostatic chuck 17 formed on the upper surface of the susceptor 16. The susceptor 16 is connected to a high frequency power source 20 through a power supply rod 18 and a matching unit 19. The high frequency power supply 20 supplies relatively low high frequency power, for example, high frequency power of 13.56 MHz or less to the susceptor 16, and generates a bias potential in the susceptor 16. As a result, ions in the plasma generated in the processing space PS between the mounting table 12 and the window member 14 are drawn into the substrate S mounted on the mounting table 12.

  The electrostatic chuck 17 is made of a dielectric member containing an electrode plate 21, and a DC power source 22 is connected to the electrode plate 21. The electrostatic chuck 17 electrostatically attracts the substrate S to the mounting table 12 by electrostatic force caused by a DC voltage applied from the DC power supply 22.

  A processing gas introduction port 23 is provided in the beam portion 12 that supports the window member 14, and the processing gas supplied from the processing gas supply device 24 is introduced into the chamber 11.

  The ICP antenna 13 is formed of an annular conductor or a conductor plate disposed along the upper surface of the window member 14, and is connected to a high frequency power supply 26 through a matching unit 25. In addition, in this specification and a claim, a conducting wire and a conductor board are named generically and are called a conducting wire.

  In the plasma processing apparatus 10, a high-frequency current flows through the ICP antenna 13, and the high-frequency current generates lines of magnetic force in the ICP antenna 13. The generated magnetic field lines are transmitted through the window member when the window member is formed of a dielectric as in the prior art, but when the window member 14 is formed of a conductor as in the present embodiment. Passes through a slit formed in the window member 14 or a gap between the divided pieces, and forms a magnetic field in the chamber 11. When the magnetic field changes with time, an induced electric field is generated, and electrons accelerated by the induced electric field collide with molecules or atoms of the processing gas introduced into the chamber 11 to generate plasma.

  Ions in the generated plasma are attracted to the substrate S by the bias potential of the susceptor 16, and radicals in the plasma move to reach the substrate S, and each of the substrates S is subjected to plasma processing, for example, physical etching processing or chemicals. Etching process is performed.

  FIG. 2 is a plan view of the window member and the ICP antenna in FIG. 1 when viewed along the white arrow in FIG.

  In FIG. 2, the window member 14 is divided into a plurality of divided pieces, for example, four triangular divided pieces 27, and an insulating material 28 made of a dielectric member is interposed between the divided pieces 27. Therefore, the four divided pieces 27 are not in direct contact so as not to be electrically connected to each other.

  On the other hand, the adjacent divided pieces 27 are connected to each other by one conductive wire 29 or one conductive wire 30 with a capacitor, and the window member 14 is closed by three conductive wires 29, one conductive wire 30 with a capacitor, and four divided pieces 27. A circuit 31 is formed. Since the ICP antenna 13 is disposed along the upper surface of the window member 14, the ICP antenna 13 and the closed circuit 31 are close to each other. In the present embodiment, the closed circuit 31 is surrounded by the ICP antenna 13 in plan view. As a capacitor (hereinafter referred to as “conductive capacitor”) in the conductive wire 30 with a capacitor, a variable capacitance capacitor or a fixed capacitance capacitor is used. In the present embodiment, the ICP antenna 13, the insulating material 28, the three conductors 29, the one capacitor-equipped conductor 30, and the window member 14 constitute an antenna structure.

  FIG. 3 is a diagram for explaining the induced current generated in the closed circuit in FIG.

  In FIG. 3, when a high-frequency current 32 flows through the ICP antenna 13, the high-frequency current 32 generates a magnetic force line 33 that passes through the annular portion 13 a formed by the ICP antenna 13. Since the closed circuit 31 is close to the ICP antenna 13, the magnetic force lines 33 passing through the annular portion 13 a of the ICP antenna 13 also pass through the annular portion 31 a formed by the closed circuit 31. At this time, an induced current 34 flows in the closed circuit 31 by electromagnetic induction of the magnetic lines of force 33. The induced current 34 generates a magnetic field line (hereinafter referred to as “sub-magnetic field line”) (not shown) that passes through the annular portion 31a.

  In the present embodiment, the magnetic field lines 33 pass through the gaps between the adjacent divided pieces 27 among the plurality of divided pieces 27 constituting the window member 14 and generate a magnetic field (hereinafter referred to as “main magnetic field”) in the processing space PS. Although the magnetic field lines 33 are distributed so as to draw a closed loop along the current flow path in the ICP antenna 13, the main magnetic field is generated in the annular portion 13 a of the ICP antenna 13. The secondary magnetic field lines generated by the closed circuit 31 of the window member 14 also form a magnetic field (hereinafter referred to as “sub-magnetic field”) in the processing space PS. The secondary magnetic field lines follow the current flow path in the closed circuit 31. The secondary magnetic field is generated in the annular portion 31 a of the closed circuit 31 because it is distributed so as to draw a closed loop.

  Here, if the main magnetic field and the sub magnetic field are opposite to each other in the processing space PS, they cancel each other, so that the induced electric field generated in the processing space PS by the magnetic field becomes weak, and the plasma generation efficiency decreases.

Therefore, in the present embodiment, the direction in which the induced current 34 flows is the same as the direction in which the high-frequency current 32 flows in order to make the directions of the main magnetic field and the sub-magnetic field the same. As disclosed in Patent Document 1 described above, the induced current 34 flowing through the closed circuit 31 is expressed by the following approximate expression (1).
I _IND ≈ −MωI _RF / (L _S −1 / C _S ω) (1)
Here, I _IND is the induced current 34, M is the mutual inductance between the ICP antenna 13 and the closed circuit 31, ω is the angular frequency, I _RF is the high frequency current 32, L _S is the self-inductance of the closed circuit 31, and C _S is The capacitance of the lead capacitor, L _S −1 / C _S ω, is the reactance of the closed circuit 31.

From the approximate expression (1), when the reactance of the closed circuit 31 is made negative, the sign (positive or negative) of I _IND (inductive current 34) becomes the same as the sign of I _RF (high frequency current 32), and the induced current 34 The direction in which the high frequency current 32 flows is the same as the direction in which the high frequency current 32 flows. In this embodiment, the capacitance (C _S ) of the lead wire capacitor is adjusted so that the reactance of the closed circuit 31 becomes negative. When the lead wire capacitor is a fixed capacitance capacitor, the capacitance is adjusted by replacing the lead wire capacitor.

  As described above, by making the reactance of the closed circuit 31 negative, the direction in which the induced current 34 flows is the same as the direction in which the high-frequency current 32 flows, so that the main magnetic field and the sub-magnetic field are in the same direction in the processing space PS. The induced electric field generated in the processing space PS can be strengthened. As a result, even if the magnetic lines of force 33 can only pass through the gaps between the adjacent divided pieces 27 among the plurality of divided pieces 27 constituting the window member 14, it is possible to prevent the plasma generation efficiency from being lowered. Can do.

  That is, according to the plasma processing apparatus 10 according to the present embodiment, the configuration of the apparatus can be simplified and plasma generation can be performed without adding an antenna such as a floating coil as in Patent Document 1 described above. A decrease in efficiency can be prevented.

  Further, in order to efficiently generate the induced current 34, it is preferable to reduce the absolute value of the reactance of the closed circuit 31 and to increase the capacitance of the conducting capacitor from the above approximate expression (1).

  FIG. 4 is a graph showing the relationship between the capacitance of the lead wire capacitor and the induced current.

The inventors set the pressure in the chamber 11 of the plasma processing apparatus 10 to 10 mTorr by the exhaust apparatus 15 and processed the mixed gas of Ar gas and O ₂ gas as the processing gas so that the flow rates become 300 sccm and 30 sccm, respectively. The gas was introduced into the chamber 11 through the gas inlet 23, high frequency power having a frequency of 13.56 MHz was supplied from the high frequency power supply 26 to the ICP antenna 13 at 1000 W, and the capacitance of the lead capacitor in the closed circuit 31 was increased. However, as shown in the graph of FIG. 4, it was confirmed that the induced current 34 increased at an accelerated rate. It was also confirmed that the high frequency current 32 decreased as the induced current 34 increased.

  The reason why the high-frequency current 32 is decreased is considered to be that the proportion of the supplied high-frequency power consumed for generating the induction current 34 is increased and the proportion consumed for generating the high-frequency current 32 is decreased.

  Further, it was confirmed that the increase degree of the induced current 34 was larger than the decrease degree of the high-frequency current 32. In other words, when high frequency power of the same magnitude is supplied to the ICP antenna 13, compared to the value of the high frequency current 32 when the high frequency current 32 is supplied only to the ICP antenna 13 without supplying the induction current 34 to the closed circuit 31. It was confirmed that the total value of the high-frequency current 32 and the induced current 34 when the induced current 34 was passed not only through the ICP antenna 13 but also through the closed circuit 31 was increased. This is considered to be because the reactance of the closed circuit 31 is greatly reduced from the reactance of the ICP antenna 13 when changing the capacitance of the lead wire capacitor, and as a result, the generation efficiency of the induced current 34 is increased.

  The inventors of the present invention have found that the induction current 34 does not flow through the closed circuit 31 under the above-described conditions while the high frequency power of 13.56 MHz supplied from the high frequency power supply 26 to the ICP antenna 13 is maintained at 1000 W, and As a result, it was confirmed that the plasma electron density in the processing space PS increased by about 40%. This is because the total value of the high frequency current 32 and the induced current 34 can be made larger than the value of the high frequency current 32 when the induced current 34 is not passed through the closed circuit 31 by passing the induced current 34 through the closed circuit 31, and as a result It was considered that a stronger magnetic field could be generated in the chamber 11.

  That is, according to the plasma processing apparatus 10 according to the present embodiment, even when high frequency power of the same magnitude is supplied to the ICP antenna 13, the induced current is generated using the closed circuit 31 in addition to the ICP antenna 13. By generating 34, the plasma generation efficiency can be improved.

  In addition, since the generation efficiency of the induction current 34 is high, in order to further improve the plasma generation efficiency when high frequency power of the same magnitude is supplied to the ICP antenna 13, the reactance of the closed circuit 31 maintains a negative value. It is preferable to increase the induced current 34 by decreasing the absolute value of the reactance of the closed circuit 31 by increasing the capacitance of the lead capacitor within the range. Furthermore, when controlling the plasma density, if it is desired to increase the plasma density in the chamber 11, the induced current 34 is reduced by increasing the capacitance of the lead capacitor and decreasing the absolute value of the reactance of the closed circuit 31. To increase the plasma generation efficiency, thereby increasing the plasma density. If the plasma density in the chamber 11 is desired to be reduced, the capacitance of the lead capacitor is reduced to achieve a closed circuit. By improving the absolute value of the reactance of 31, the induction current 34 can be reduced to reduce the plasma generation efficiency, thereby reducing the plasma density.

  Since the secondary magnetic field is generated in the annular portion 31a of the closed circuit 31 and the secondary magnetic field also generates an induced electric field, the distribution of plasma in the chamber 11 can be controlled by adjusting the position of the closed circuit 31. . For example, as shown in FIG. 2, each conductor 29 and capacitor-equipped conductor 30 are arranged symmetrically with respect to the center of the ICP antenna 13, and the closed circuit 31 is formed symmetrically with respect to the center of the ICP antenna 13. Can be generated symmetrically with respect to the center of the ICP antenna 13. In FIG. 2, since there is only one lead wire 30 with a capacitor, the arrangement is asymmetric with respect to the center of the ICP antenna 13. However, as will be described later, for example, they face each other across the center of the ICP antenna 13. By replacing the conducting wire 29 at the position with a conducting wire with a capacitor and arranging it symmetrically, it is possible to generate plasma with better symmetry.

  Further, since the main magnetic field is generated in the annular portion 13a of the ICP antenna 13, and the main magnetic field generates an induction electric field, from the viewpoint of uniformizing plasma processing applied to the substrate S, as shown in FIG. The center of the ICP antenna 13 is preferably coincident with the center of the chamber 11, so that not only the plasma by the sub-magnetic field but also the plasma by the main magnetic field can be generated symmetrically with respect to the center of the chamber 11.

  Furthermore, the position of the closed circuit 31 may be adjusted in accordance with the plasma distribution in the chamber 11. For example, when the plasma density in the center is low in the chamber 11, as shown in FIG. The lead wire 30 with a capacitor is arranged close to the center of the ICP antenna 13, and the closed circuit 31 is formed from the center of the ICP antenna 13 (first modification). As a result, plasma generated by the sub magnetic field can be generated intensively at the center of the ICP antenna 13, that is, the center of the chamber 11, thereby improving the plasma distribution in the chamber 11.

  Although the present invention has been described above by using the embodiment, the present invention is not limited to the above-described embodiment.

  For example, from the viewpoint of generating plasma in a wide range in the chamber 11, as shown in FIGS. 2 and 5, each lead wire 29 and the lead wire 30 with a capacitor are offset from the ICP antenna 13 and the closed circuit 31 is placed in the ICP antenna. It is preferably offset from 13. Thereby, the plasma by a submagnetic field can be generated in the position away from the plasma by a main magnetic field. Here, the offset refers to a positional relationship that does not overlap in a direction perpendicular to a plane parallel to the closed circuit 31 and the ICP antenna 13.

  The window member 14 is not limited to the case where the window member 14 is divided into four divided pieces 27. The window member 14 is divided into at least two divided pieces 27 and insulated from each other, and a closed circuit 31 is formed by the conductive wire 29 and the conductive wire 30 with a capacitor. It only has to be done. For example, the window member 14 may be divided into 12 divided pieces 27 as shown in FIGS. 6 and 7, and the window member 14 may be divided into 16 divided pieces 27 as shown in FIGS. It may be divided.

  Further, each closed circuit 31 may have a plurality of conductors 30 with capacitors as shown in FIG. 6 (second modified example). For example, as shown in FIG. You may connect all the division | segmentation pieces 27 with the conducting wire 30 with a capacitor | condenser (3rd modification). Thereby, the symmetry of the closed circuit 31 is enhanced, and therefore the symmetry of the distribution of plasma generated by the sub-magnetic field in the chamber 11 can be further improved.

  For example, even when the window member 14 is divided into the same 16 divided pieces 27, each divided piece 27 may be formed of triangular divided pieces as shown in FIG. 9), it may be composed of rectangular divided pieces as shown in FIG. 9 (fifth modification).

  Further, a plurality of closed circuits 31 may be formed in the window member 14. In particular, when a plurality of ICP antennas 13 are arranged, it is preferable that each closed circuit 31 is arranged close to each other corresponding to each ICP antenna 13. Thereby, the induction current 34 can be efficiently generated in each corresponding closed circuit 31 by the high-frequency current 32 flowing through each ICP antenna 13. Further, the ICP antennas 13 may be arranged concentrically as shown in FIG. 6, or may be individually arranged in parallel as shown in FIG. 10 (sixth modification). At this time, by adjusting the reactance of each closed circuit 31 individually, the strength of the sub-magnetic field generated along each closed circuit 31 is individually adjusted, thereby locally increasing the plasma density in the chamber 11. As a result, the density distribution of the plasma can be controlled more finely.

  Further, when a plurality of closed circuits 31 are formed in the window member 14, each closed circuit 31 does not have to correspond to a different ICP antenna 13, and for example, as shown in FIGS. Four closed circuits 31 may be arranged for the antenna 13 (seventh modification), and four closed circuits 31 may be arranged for each of the four ICP antennas 13 (eighth modification). Example). Further, as shown in FIG. 13, eight closed circuits 31 may be arranged for one ICP antenna 13 (the ninth modification), and as shown in FIG. 16 closed circuits 31 may be arranged (tenth modification).

  Furthermore, the present invention may be applied to a plasma processing apparatus that performs plasma processing on a disk-shaped semiconductor wafer. In this case, the window member 14 has a disk shape, but as shown in FIGS. 15 and 16. These are divided into a plurality of divided pieces 27 and a closed circuit 31 is provided corresponding to each ICP antenna 13. Also in this case, in each closed circuit 31, each divided piece 27 may be connected by a lead wire 29 or a lead wire 30 with a capacitor (FIG. 15, eleventh modification), or each split piece 27 may be connected only to the lead wire 30 with a capacitor. May be connected (FIG. 16, 12th modification).

  Further, the present invention may be applied only to a part of the window member 14, and in this case, as shown in FIG. 17, a part of the window member 14 is divided into a plurality of divided pieces 27, and each ICP antenna 13. A closed circuit 31 is provided corresponding to (13th modification).

  Further, two adjacent segment pieces 27 may be connected not only by one conductor 29 or capacitor-equipped conductor 30 but also by a plurality of conductors 29 or a capacitor-provided conductor 30 as shown in FIG. 18 (fourteenth modification). Example). Thereby, the several closed circuit 31 can be formed easily.

  In addition, as shown in FIG. 19, the insulating material 28 between two adjacent divided pieces 27 is utilized as a dielectric, and the capacitance of a part 28 a of the insulating material 28 is adjusted to adjust the two divided pieces 27 and A capacitor may be constituted by a part 28a of the insulating material 28 (a fifteenth modification). As shown in FIG. 20, the thickness of a part 28b of the insulating material 28 between two adjacent divided pieces 27 is set. The capacitor may be constituted by two thin pieces 27 and a part 28b of the insulating material 28 (a sixteenth modification). Thereby, the closed circuit 31 can be formed without using the conducting wire 30 with a capacitor, and the number of parts can be reduced.

  Furthermore, each conducting wire 29 and the conducting wire 30 with the capacitor may not be arranged symmetrically with respect to the center of the ICP antenna 13. For example, as shown in FIG. 21, the conducting wire 30 with a capacitor and a part of the conducting wire 29 may be arranged away from the center of the ICP antenna 13 and the remaining conducting wires 29 may be arranged apart from the center of the ICP antenna 13 ( Seventeenth modification). Thereby, the closed circuit 31 can be unevenly distributed with respect to the ICP antenna 13, that is, the center of the chamber 11. As a result, for example, when the plasma due to the main magnetic field is unevenly distributed in the chamber 11 due to the internal structure of the chamber 11, the closed circuit 31 is unevenly distributed so as to face the portion where the plasma density due to the main magnetic field is low. The plasma can be evenly distributed in 11.

  In addition, since the present invention improves the plasma generation efficiency, the present invention is applied not only to the plasma processing apparatus 10 that performs plasma processing on the substrate S inside, but also to a plasma generation apparatus as a plasma source for plasma used in various applications. be able to. For example, as shown in FIG. 22, the plasma generating apparatus 35 to which the present invention is applied is obtained by removing the mounting table 12 and the components related to the mounting table 12 from the plasma processing apparatus 10 of FIG. 11 can be used as a remote plasma apparatus that takes out plasma from 11 and supplies it to other locations.

DESCRIPTION OF SYMBOLS 10 Plasma processing apparatus 11 Chamber 12 Mounting stand 13 ICP antenna 14 Window member 26 High frequency power supply 27 Split piece 28 Insulation material 29 Conductor 30 Conductor 31 with a capacitor Closed circuit 34 Inductive current

Claims (13)

A processing chamber that accommodates the substrate, a mounting table that is disposed inside the processing chamber and mounts the substrate, and is disposed outside the processing chamber so as to face the mounting table and is connected to a high-frequency power source. In a plasma processing apparatus comprising an inductively coupled antenna,
A wall portion of the processing chamber facing the inductively coupled antenna is configured, and further includes a window member made of a conductor interposed between the mounting table and the inductively coupled antenna,
The window member is divided into a plurality of divided pieces,
The plurality of divided pieces are not in direct contact with each other so as not to be electrically connected to each other,
At least some of the segments are connected by a conductive wire to form a closed circuit;
The closed circuit may have at least one capacitor in said wire to connect each of the divided pieces,
The plasma processing apparatus in which the electrostatic capacitance of the capacitor as the reactance of the closed circuit is negative and said Rukoto adjusted. The plasma processing apparatus according to claim 1, wherein said conductor, characterized in that are arranged symmetrically with respect to the center of the inductively coupled antenna. The plasma processing apparatus according to claim 1 or 2, wherein each of said conductors and having the capacitor. The conductor plasma processing apparatus according to any one of claims 1 to 3, characterized in that it is arranged to the inductive coupling antenna and offset. The capacitor is the capacitance variable capacitor, any one of claims 1 to 4 the capacitance of the capacitor in accordance with at least one of the density and density distribution of the processing chamber of the plasma is characterized in that it is adjusted The plasma processing apparatus according to 1. The plasma processing apparatus according to any one of claims 1 to 5, characterized in that the position of the wires in accordance with the plasma distribution in the processing chamber is adjusted. The plasma processing apparatus according to any one of claims 1 to 6, wherein a plurality of said closed circuit is formed in the window member. A plasma generator for generating plasma in a decompression chamber,
An inductively coupled antenna disposed outside the decompression chamber and connected to a high frequency power source; and a window member made of a conductor interposed between the inductively coupled antenna and the plasma in the decompression chamber,
The window member is divided into a plurality of divided pieces,
The plurality of divided pieces are not in direct contact with each other so as not to be electrically connected to each other,
At least some of the segments are connected by a conductive wire to form a closed circuit;
The closed circuit may have at least one capacitor in said wire to connect each of the divided pieces,
The electrostatic capacitance of the capacitor as the reactance of the closed circuit is negative is adjusted plasma generating apparatus according to claim Rukoto. 9. The plasma generating apparatus according to claim 8, wherein the conducting wires are arranged symmetrically with respect to the center of the inductively coupled antenna. In an antenna structure including an inductively coupled antenna connected to a high frequency power source,
A window member made of a conductor interposed between the inductively coupled antenna and the plasma generated by the inductively coupled antenna;
The window member is divided into a plurality of divided pieces,
The plurality of divided pieces are not in direct contact with each other so as not to be electrically connected to each other,
At least some of the segments are connected by a conductive wire to form a closed circuit;
The closed circuit may have at least one capacitor in said wire to connect each of the divided pieces,
Antenna structures capacitance of the capacitor as a reactance of the closed circuit is negative and said Rukoto adjusted. The antenna structure according to claim 10, wherein the conducting wire is disposed symmetrically with respect to a center of the inductively coupled antenna. An inductively coupled antenna connected to a high frequency power supply; and a window member made of a conductor interposed between the inductively coupled antenna and the plasma, the window member being divided into a plurality of divided pieces, and the plurality of divided pieces Is a plasma generation method using antenna structures that are insulated from each other,
Connecting at least some of the divided pieces with a conductor having at least one capacitor to form a closed circuit;
A plasma generation method comprising adjusting a capacitance of the capacitor so that a reactance of the closed circuit becomes negative. 13. The plasma generation method according to claim 12 , wherein the capacitor is a variable capacitance capacitor, and the capacitance of the capacitor is adjusted according to at least one of plasma density and density distribution in the processing chamber.

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