JP6084784B2 - 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 window made of a dielectric, for example, 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. In addition, it is expected that the size of a substrate housed in a chamber and subjected to plasma processing, for example, FPD (Flat Panel Display), will continue to increase, so it is necessary to increase the size of the dielectric window facing the substrate. Since it is necessary to ensure rigidity when the size 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

    Also in the ICP antenna facing the conductor window, it is conceivable to reinforce the induction electric field by applying the technique of Patent Document 1 described above. However, in the technique of Patent Document 1 described above, the ICP antenna and the conductor window are Since it is necessary to provide a separate floating coil, there is a problem that the configuration of the apparatus 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, the plasma processing apparatus is one wall portion of the processing chamber facing the inductively coupled antenna, A window member made of a conductor constituting the one wall portion that is not directly electrically connected to another wall portion and interposed between the mounting table and the inductively coupled antenna, and both ends connected to the window member and a conductive wire that is, the window member and the conductive wire to form a closed circuit, wherein the conductors have at least one capacitor, said closed circuit is not present in said window member in a plane parallel to, the closed The surface where the circuit exists And Kimado member is characterized by crossing.

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, the plasma processing apparatus is one wall portion of the processing chamber facing the inductively coupled antenna, A window member made of a conductor constituting the one wall portion that is not directly electrically connected to another wall portion and interposed between the mounting table and the inductively coupled antenna, and both ends connected to the window member The window member and the conductor form a closed circuit, the conductor has at least one capacitor, the window member is divided into a plurality of divided pieces, and one end of the conductor is one Contact the split piece The other end of the conducting wire is connected to the other divided piece, and the one divided piece and the other divided piece are adjacent to each other and separated by a dielectric disposed therebetween so that they are not electrically connected to each other. A part of the dielectric between the one divided piece and the other divided piece is formed thinly without being in direct contact with the first divided piece.

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; and a conductor wire connected at both ends to the window member; the window member and the conductor wire form a closed circuit. the conductors have at least one capacitor, said closed circuit is not present in said window member in a plane parallel to, and the surface on which the closed circuit is present and wherein the window member is characterized by crossing.

In order to achieve the above object, an antenna structure according to 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. to a window member made of a conductor, and a conductor having both ends connected to the window member, said window member and said wire form a closed circuit, wherein the conductors have at least one capacitor, the closed The circuit does not exist in a plane parallel to the window member, and the plane on which the closed circuit exists intersects the window member .

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, a window member made of a conductor interposed between the inductively coupled antenna and the plasma, and a conductive wire. The conductive wire is a plasma generation method using an antenna structure having at least one capacitor, wherein both ends of the conductive wire are connected to the window member to form a closed circuit, and the reactance of the closed circuit becomes negative The capacitance of the capacitor is adjusted so that the closed circuit does not exist in a plane parallel to the window member, and the surface where the closed circuit exists and the window member intersect each other. It is connected to a window member at both ends .

  According to the present invention, a closed circuit is formed by connecting both ends of a conductor to a window member made of a conductor facing an inductively coupled antenna connected to a high-frequency power source, and the conductor has at least one capacitor. As a result, the magnetic field generated from the inductively coupled antenna generates an induced current in the closed circuit by electromagnetic induction, and the induced current is generated along the window member that generates a magnetic field along the window member constituting the closed circuit. Since the magnetic field generates an induced electric field, and as a result, plasma is generated, an independent floating coil can be created by controlling the induced current generated in the closed circuit by changing the capacitance of the capacitor and adjusting the reactance of the closed circuit. A decrease in plasma generation efficiency can be prevented without the provision. 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. It is a perspective view which shows schematically the structure of the window member and ICP antenna in FIG. 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 presence or absence of a closed circuit, and the distribution of the electron density in processing space. It is a perspective view which shows the 1st modification of the window member of FIG. 2, and an ICP antenna. It is a perspective view which shows the 2nd modification of the window member of FIG. 2, and an ICP antenna. It is a perspective view which shows the 3rd modification of the window member of FIG. 2, and an ICP antenna. It is a perspective view which shows the 4th modification of the window member of FIG. 2, and an ICP antenna. It is a perspective view which shows the 5th modification of the window member of FIG. 2, and an ICP antenna. It is a perspective view which shows the 6th modification of the window member of FIG. 2, and an ICP antenna. It is a perspective view which shows the 7th modification of the window member of FIG. 2, and an ICP antenna. It is a perspective view which shows the 8th modification of the window member of FIG. 2, and an ICP antenna. It is a perspective view which shows the 9th modification of the window member of FIG. 2, and an ICP antenna. It is a perspective view which shows the 10th modification of the window member and ICP antenna of FIG. It is a perspective view which shows the 11th modification of the window member of FIG. 2, and an ICP antenna. 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 supported by a support portion 12 provided in the chamber 11 via at least an insulating member or an insulating coating (both not shown). As a result, the window member 14 and the chamber 11 are not in direct contact and are not electrically connected. In addition, by controlling the thickness of the insulating member or insulating film that isolates the window member 14 and the chamber 11 from each other, it is possible to suppress inductive coupling between the window member 14 and the chamber 11.

  The window member 14 has a size that can cover at least the entire surface of the substrate S mounted on the mounting table 12. In addition, the window member 14 may be comprised from the some division | segmentation piece 35 so that it may mention later.

  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 on the side wall of the chamber 11, and the processing gas supplied from the processing gas supply device 24 is introduced into the chamber 11. However, since it is desirable to supply the processing gas not from the side wall of the chamber 11 but from the upper part of the chamber 11 from the viewpoint of processing uniformity, for example, when the window member 14 is constituted by a plurality of divided pieces 35. May be provided with a gas inlet in a beam portion supporting each divided piece 35.

  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 pass through the window member when the window member is formed of a dielectric as in the conventional case, but when the window member 14 is formed of a conductor as in the present embodiment. Passes through the peripheral edge of the window member 14 and passes through the slit when the window member 14 is formed with a slit, and each divided piece 35 when the window member 14 is composed of a plurality of divided pieces 35. A magnetic field is formed in the chamber 11 through the gap. 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 perspective view schematically showing the configuration of the window member and the ICP antenna in FIG.

  In FIG. 2, the window member 14 has a rectangular shape, and the ICP antenna 13 includes two linear parallel portions 13 a arranged in parallel with the window member 14, and two rising vertically from the both ends of the parallel portion 13 a with respect to the window member 14. And vertical portions 13b and 13c. The parallel portion 13a is disposed partially along the diagonal line of the window member 14, the vertical portion 13b is connected to the high frequency power supply 26 through the matching unit 25, and the vertical portion 13c is grounded. An insulating material 27 is disposed between the window member 14 and the connecting portion 13d of the parallel portion 13a and the vertical portion 13b, and the connecting portion 13e of the parallel portion 13a and the vertical portion 13c, and the window member 14 is connected to the ICP antenna 13. Insulated.

  Further, the plasma processing apparatus 10 has a conductive wire 28 whose both ends are connected to both vertices 14 a and 14 b related to one diagonal line of the window member 14, and the conductive wire 28 has a capacitor 29.

  The conducting wire 28 and the window member 14 form an annular closed circuit 30 indicated by a broken line in the figure, but the closed circuit 30 does not exist in a plane parallel to the window member 14, and the surface where the closed circuit 30 exists and the window member 14. Are connected to the window member 14 at both ends thereof. Further, since the parallel portion 13a of the ICP antenna 13 is disposed along the upper surface of the window member 14, the ICP antenna 13 and the closed circuit 30 are close to each other. In the present embodiment, the ICP antenna 13, the window member 14, and the conducting wire 28 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 31 flows through the ICP antenna 13, the high frequency current 31 generates a magnetic force line 32 around the ICP antenna 13. Since the closed circuit 30 is close to the ICP antenna 13, the magnetic lines of force 32 generated around the ICP antenna 13 pass through the annular portion 30 a formed by the closed circuit 30. At this time, an induced current 33 flows in the closed circuit 30 by electromagnetic induction of the magnetic lines of force 32, and the induced current 33 generates magnetic lines of force (hereinafter referred to as “sub-magnetic lines of force”) 34 that pass through the annular portion 30 a.

  In the present embodiment, the magnetic field lines 32 pass through the peripheral edge of the window member 14 to generate a magnetic field (hereinafter referred to as “main magnetic field”) in the processing space PS, but the magnetic field lines 32 are distributed along the window member 14. Therefore, the main magnetic field is also generated along the window member 14. Further, the secondary magnetic field lines 34 also pass through the peripheral edge of the window member 14 to generate a magnetic field (hereinafter referred to as “sub-magnetic field”) in the processing space PS, but the secondary magnetic field lines 34 are also generated along the window member 14. Therefore, the main magnetic field and the sub magnetic field overlap in the processing space PS.

  At this time, 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 is weakened, and the plasma generation efficiency is reduced.

Therefore, in the present embodiment, the direction in which the induced current 33 flows is the same as the direction in which the high-frequency current 31 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 33 flowing through the closed circuit 30 is expressed by the following approximate expression (1).
I _IND ≈ −MωI _RF / (L _S −1 / C _S ω) (1)
Here, I _IND is an induction current 33, M is a mutual inductance between the ICP antenna 13 and the closed circuit 30, ω is an angular frequency, I _RF is a high frequency current 31, L _S is a self-inductance of the closed circuit 30, and C _S is The capacitance of the capacitor 29, L _S −1 / C _S ω, is the reactance of the closed circuit 30.

From the above approximate expression (1), when the reactance of the closed circuit 30 is made negative, the sign (positive or negative) of I _IND (inductive current 33) becomes the same as the sign of I _RF (high frequency current 31). Is the same as the direction in which the high-frequency current 31 flows. In this embodiment, the capacitance (C _S ) of the capacitor 29 is adjusted so that the reactance of the closed circuit 30 becomes negative. If the capacitor 29 is a fixed capacitance capacitor, the capacitance is adjusted by replacing the capacitor 29.

  As described above, by making the reactance of the closed circuit 30 negative, the direction in which the induced current 33 flows can be made the same as the direction in which the high-frequency current 31 flows, so that the main magnetic field and the sub magnetic field have 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 field lines 32 are attenuated when passing through the peripheral edge of the window member 14 and reaching the processing space PS, it is possible to prevent the plasma generation efficiency from being lowered.

  That is, according to the plasma processing apparatus 10 according to the present embodiment, it is possible to simplify the configuration of the apparatus and prevent a decrease in plasma generation efficiency without providing an independent floating coil.

  Further, in order to efficiently generate the induced current 33, it is preferable to reduce the absolute value of the reactance of the closed circuit 30 and to increase the capacitance of the capacitor 29 from the approximate expression (1).

  FIG. 4 is a graph showing the relationship between the presence or absence of a closed circuit and the distribution of electron density in the processing space.

  In the plasma processing apparatus 10, the inventors remove the insulating material 27 and connect the ICP antenna 13 directly to the window member 14 through the connecting portions 13 d and 13 e, so that the window member 14 and the mounting table 12 are paired in parallel. The electron density when functioning as a flat plate electrode is indicated by “●”, the capacitance of the capacitor 29 is minimized, and the reactance of the closed circuit 30 is maximized. The electron density when only the antenna 13 is functioned is indicated by “▲”, and the induced current 33 is caused to flow through the closed circuit 30 by increasing the capacitance of the capacitor 29 and reducing the reactance of the closed circuit 30, thereby generating an ICP antenna. The electron density when not only 13 but also the closed circuit 30 functions as an antenna by causing the induced current 33 to flow through the closed circuit 30 is indicated by “x”.

  When the window member 14 functions as a parallel plate electrode paired with the mounting table 12, the plasma is uniformly distributed in the processing space PS and the electron density is uniform, but only an electric field is generated in the processing space PS. Since no magnetic field is generated, electrons are not accelerated in the processing space PS and do not collide with the molecules and electrons of the processing gas so much. As a result, the plasma generation efficiency is lowered, and the electron density is lowered overall. .

  When only the ICP antenna 13 is functioned, a main magnetic field is generated in the processing space PS, but the parallel portion 13a does not exist in the vicinity of both vertices 14a and 14b of the window member 14, and therefore the main magnetic field is generated by the window member. It was found that the strength was particularly strong in the vicinity of the center portion of 14, and as a result, the electron density was particularly high near the center portion of the window member 14.

  On the other hand, when not only the ICP antenna 13 but also the closed circuit 30 functions as an antenna, not only a main magnetic field but also a sub-magnetic field is generated in the processing space PS, so that a strong magnetic field is generated in the processing space PS. It turned out that an electron density becomes high in the whole processing space PS. In particular, the two apexes 14a and 14b, which are the connection positions of the conducting wire 28 and the window member 14, exist near the peripheral edge of the window member 14, and the magnetic lines of force can pass therethrough with a high magnetic flux density. , 14b, the sub-magnetic field becomes stronger, and thus the electron density is locally increased near both vertices 14a, 14b.

  That is, according to the plasma processing apparatus 10 according to the present embodiment, a strong magnetic field is applied to the processing space PS by causing the closed circuit 30 to function as an antenna by causing the induced current 33 to flow not only to the ICP antenna 13 but also to the closed circuit 30. It was found that the generation efficiency of plasma can be improved.

  Further, as described above, the connection position between the conductive wire 28 and the window member 14 can pass the magnetic lines of force with a high magnetic flux density, and the sub-magnetic field can be strengthened in the vicinity of the connection position. By changing the connection position between the conductor 28 and the window member 14 according to the plasma distribution, the plasma distribution in the processing space PS can be made uniform. For example, if the conductor 28 is connected to the window member 14 at a position facing the portion where the plasma density is to be increased in the processing space PS, the sub-magnetic field in the portion where the plasma density is desired to be increased can be increased. The plasma generation efficiency by the sub magnetic field can be improved and the plasma density can be increased.

  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, the parallel portion 13a of the ICP antenna 13 does not need to be arranged along the diagonal line of the window member 14, and may be arranged in parallel with the long side of the window member 14 as shown in FIG. Variation of). Further, the conductive wire 28 does not need to be connected to both the vertices 14a and 14b of the window member 14, and particularly if the magnetic lines 32 can pass through the annular portion 30a of the closed circuit 30 formed together with the window member 14, the connecting portion is Not constrained. For example, when the parallel part 13a of the ICP antenna 13 is arranged in parallel with the long side of the window member 14, the conductor 28 is connected to both short sides 14c and 14d of the window member 14 as shown in FIG. 30 may be formed parallel to the long side of the window member 14.

  Further, the conductor 28 does not need to be connected to the peripheral portion of the window member 14, and as shown in FIG. 6, the conductor 28 is connected to the window member 14 as long as the magnetic lines 32 can pass through the annular portion 30 a of the closed circuit 30. You may connect to places other than a peripheral part (2nd modification). That is, the closed circuit 30 may be smaller than the window member 14. Further, the conductor 28 is connected to a portion other than the peripheral portion of the window member 14 to reduce the closed circuit 30, thereby limiting the range in which the secondary magnetic field is generated and locally improving the plasma distribution in the processing space PS. It can be carried out.

  Moreover, the parallel part 13a in the ICP antenna 13 may not be formed in a straight line shape, and may be wound and formed in a coil shape as shown in FIG. 7, for example (third modified example). Furthermore, if the magnetic line 32 can pass through the annular portion 30a of the closed circuit 30, the conductive wire 28 is also wound so as to form a passage surface 30b through which the magnetic line 32 passes, for example, as shown in FIG. It may be formed in a coil shape (fourth modification).

  Furthermore, the surface where the closed circuit 30 exists and the window member 14 do not need to intersect. For example, the surface where the closed circuit 30 exists and the window member 14 may be parallel (fifth modification). In this case, as shown in FIG. 9, an annular portion 28 a is formed by the conducting wire 28, and the surface on which the annular portion 28 a exists is parallel to the window member 14.

  Further, the window member 14 is divided into a plurality of divided pieces 35, and the divided pieces 35 are separated from each other by a dielectric (not shown) and do not have to be in direct contact with each other so as not to be electrically connected to each other (sixth) Modification). In this case, as shown in FIG. 10, the adjacent two divided pieces 35 are connected by a conductive wire 36 (another conductive wire) and are electrically connected to each other, and one end of the conductive wire 28 is connected to the one divided piece 35. The other end is connected to another divided piece 35. In particular, in one divided piece 35, one end of the conductive wire 28 is connected to an edge portion 35a away from the place where the conducting wire 36 is connected, and in the other divided piece 35, the edge portion away from the place where the conducting wire 36 is connected. The other end of the conducting wire 28 is connected to 35b. Thereby, the closed circuit 30 along the arrangement direction of two adjacent divided pieces 35 can be formed. In addition, as shown in FIG. 11, the conducting wire 36 may also have the capacitor | condenser 37 (7th modification).

  The number of divided pieces 35 constituting the closed circuit 30 is not limited to two. For example, when generating a wide range of sub-magnetic fields in the processing space PS, the closed circuit 30 is formed by combining three or more divided pieces 35. It is preferable to do this. That is, the distribution of the sub magnetic field in the processing space PS can be arbitrarily adjusted by changing the combination of the plurality of divided pieces 35.

  Further, when the closed circuit 30 is configured by a plurality of divided pieces 35, the ICP antenna 13 does not have to face all the divided pieces 35 as long as the magnetic lines of force 32 can pass through the annular portion 30 a of the closed circuit 30. For example, as shown in FIG. 12, one end of the conducting wire 28 is connected to the top portion 35 c of one divided piece 35, and the other end of the conducting wire 28 is connected to the top portion 35 d of the other divided piece 35. While the closed circuit 30 is formed by the conducting wire 28, the ICP antenna 13 may face only one divided piece 35 (eighth modification). At this time, since the induced current 33 flows through the other divided pieces 35 constituting the closed circuit 30, a magnetic field may be generated also in the portion of the processing space PS facing the other divided pieces 35 where the ICP antenna 13 does not face. it can.

  Further, when the closed circuit 30 is configured by a plurality of divided pieces 35, as shown in FIG. 13, a part 38a of the dielectric 38 between two adjacent divided pieces 35 may be formed thinly. The capacitance of the part 38a of the thinly formed dielectric 38 is increased and functions as a capacitor. Therefore, the closed circuit 30 can be formed without providing the capacitor 29 on the conducting wire 28, so that the configuration of the closed circuit 30 can be simplified and the number of parts can be reduced (the ninth modification).

  Further, when the window member 14 is divided into a plurality of divided pieces 35, as shown in FIG. 14, a conductive wire 28 is provided corresponding to each of the divided pieces 35, and both ends of each of the conductive wires 28 are provided in each of the divided pieces 35. May be connected to form a closed circuit 30 in each of the divided pieces 35 (a tenth modification). In this case, the sub-magnetic field in the part of the processing space PS facing each divided piece 35 can be individually adjusted, so that the plasma distribution in the processing space PS can be adjusted more finely.

  In order to form a uniform plasma on the entire surface of the window member 14, it is desirable to provide the conductive wires 28 corresponding to all the divided pieces 35. However, the shape of the processing space PS (for example, an asymmetric shape) or the like When there is a factor causing the density distribution to be non-uniform, or when it is desired to make the density distribution of the plasma intentionally biased, the lead wires 28 correspond to some of the divided pieces 35 instead of all of the divided pieces 35. May be provided. That is, according to the shape of the processing space PS, the content of the plasma processing, and the like, in the present embodiment, it is only necessary that the conductive wire 28 is provided corresponding to at least one divided piece 35.

  Further, the shape of the window member 14 is not limited to a rectangle, and may be a circle, for example. Also in this case, as shown in FIG. 15, the window member 14 is divided into a plurality of divided pieces 39, and the adjacent divided pieces 39 are connected by the conductive wires 28 and 36 to form a closed circuit (the eleventh modification). Example).

  In the plasma processing apparatus 10 described above, the capacitor 29 included in the conducting wire 28 is a capacitor with a fixed capacity, but the capacitor 29 may be configured with a variable capacity capacitor. In this case, the value of the induced current 33 is changed by adjusting the capacitance of the capacitor 29 according to the density of the plasma in the processing space PS, and the strength of the sub magnetic field generated in the processing space PS is changed. Thereby, the density distribution of the plasma in the processing space PS can be adjusted.

  In addition, since the present invention improves the plasma generation efficiency, the present invention can be applied not only to the plasma processing apparatus 10 that performs plasma processing on the substrate S but also to a plasma generation apparatus as a plasma source of plasma used in various applications. Can do. For example, as shown in FIG. 16, the plasma generation apparatus 40 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. It can be used as a remote plasma apparatus that takes out plasma from the chamber 11 and supplies it to other locations.

PS processing space S substrate 10 plasma processing apparatus 11 chamber 12 mounting table 13 ICP antenna 14 window member 28, 36 conducting wire 29 capacitor 30 closed circuit 35, 39 split piece 38 dielectric 40 plasma generating apparatus

Claims (16)

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,
One wall portion of the processing chamber facing the inductively coupled antenna, the first wall portion not electrically connecting directly to the other wall portion of the processing chamber, and the mounting table and the induction A window member made of a conductor interposed between the coupled antennas;
A conductive wire having both ends connected to the window member;
The window member and the conductor form a closed circuit;
The conductor has at least one capacitor;
The plasma processing apparatus, wherein the closed circuit does not exist in a plane parallel to the window member, and the plane on which the closed circuit exists intersects the window member.   2. The plasma processing apparatus according to claim 1, wherein the capacitance of the capacitor and a predetermined frequency for generating plasma of the high-frequency power source are adjusted so that reactance of the closed circuit becomes negative.   The plasma processing apparatus according to claim 1, wherein the conductive wire is connected to the window member at a position facing a portion where the plasma density in the processing chamber is desired to be increased.   The window member is divided into a plurality of divided pieces, the conductive wires are provided corresponding to at least one of the divided pieces, and both ends of the conductive wires are connected to the divided pieces provided corresponding to the conductive wires. The plasma processing apparatus according to claim 1, wherein the plasma processing apparatus is a plasma processing apparatus. The window member is divided into a plurality of divided pieces,
One end of the conducting wire is connected to one of the divided pieces, the other end of the conducting wire is connected to the other divided piece, and the one divided piece and the other divided piece are separated by a conducting wire different from the conducting wire. The plasma processing apparatus according to claim 1, wherein the plasma processing apparatus is connected.   6. The plasma processing apparatus according to claim 5, wherein the inductively coupled antenna faces only the one divided piece. 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,
One wall portion of the processing chamber facing the inductively coupled antenna, the first wall portion not electrically connecting directly to the other wall portion of the processing chamber, and the mounting table and the induction A window member made of a conductor interposed between the coupled antennas;
A conductive wire having both ends connected to the window member;
The window member and the conductor form a closed circuit;
The conductor has at least one capacitor;
The window member is divided into a plurality of divided pieces,
One end of the conducting wire is connected to one of the divided pieces, and the other end of the conducting wire is connected to the other divided piece,
The one divided piece and the other divided piece are adjacent to each other and separated by a dielectric disposed therebetween, and are not in direct contact with each other so as not to be electrically connected to each other;
A part of the dielectric between the one divided piece and the other divided piece is formed thin.   The plasma processing apparatus according to claim 1, wherein the conducting wire is wound so as to form a passing surface through which a magnetic line of force generated from the inductively coupled antenna passes.   2. The capacitor is a variable capacitance capacitor, and a value of an induced current flowing through the closed circuit is changed by adjusting a capacitance of the capacitor in accordance with a plasma density in the processing chamber. The plasma processing apparatus of any one of thru | or 8. 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;
A window member made of a conductor interposed between the inductively coupled antenna and the plasma in the decompression chamber;
A conductive wire having both ends connected to the window member;
The window member and the conductor form a closed circuit;
The conductor has at least one capacitor;
The closed circuit does not exist in a plane parallel to the window member, and the surface on which the closed circuit exists intersects the window member.   11. The plasma generation apparatus according to claim 10, wherein the capacitance of the capacitor and a predetermined frequency for generating plasma of the high-frequency power source are adjusted so that reactance of the closed circuit becomes negative. The window member is divided into a plurality of divided pieces,
One end of the conducting wire is connected to one of the divided pieces, the other end of the conducting wire is connected to the other divided piece, and the one divided piece and the other divided piece are separated by a conducting wire different from the conducting wire. The plasma generation apparatus according to claim 10, wherein the plasma generation apparatus is connected. 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;
A conductive wire having both ends connected to the window member;
The window member and the conductor form a closed circuit;
The conductor has at least one capacitor;
The antenna structure according to claim 1, wherein the closed circuit does not exist in a plane parallel to the window member, and the plane in which the closed circuit exists intersects the window member. The window member is divided into a plurality of divided pieces,
One end of the conducting wire is connected to one of the divided pieces, the other end of the conducting wire is connected to the other divided piece, and the one divided piece and the other divided piece are separated by a conducting wire different from the conducting wire. claim 1 3 Symbol mounting of the antenna structure, characterized in that it is connected. 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, and a conductor are used, and the conductor uses an antenna structure having at least one capacitor. A plasma generation method comprising:
Connecting both ends of the conducting wire to the window member to form a closed circuit;
Adjust the capacitance of the capacitor so that the reactance of the closed circuit becomes negative,
The conducting wire is connected to the window member at both ends so that the closed circuit does not exist in a plane parallel to the window member, and the plane where the closed circuit exists and the window member intersect. Plasma generation method. The capacitor is the capacitance variable capacitor of claim 1 5, wherein changing the value of the induced current flowing through the closed circuit by adjusting the capacitance of the capacitor depending on the density of the plasma Plasma generation method.

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