JP2010135727A - Plasma processing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To execute a plasma process with high in-plane uniformity to a workpiece. <P>SOLUTION: An antenna 5 is so provided as to face a mounting table 27 via a dielectric window member 3. The antenna 5 is constituted by a plurality of linear antenna members 51 which have equal length to one another and are arranged horizontally in parallel to one another. One end side of the antenna 5 is connected to a high frequency power supply part 6 via a power supply side conductive path 61, and further the other end side is connected to a grounding point via a grounding side conductive path 62. At least one of the power supply side conductive path 61 and the grounding side conductive path 62 is provided with a potential distribution adjusting capacitor 7 for adjusting a potential distribution of the antenna 5, and the capacitor is set so that impedance of each high frequency route from the high frequency power supply part 6 to the grounding point via each antenna member 51 becomes equal. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for performing predetermined plasma processing on an object to be processed such as a glass substrate for manufacturing an FPD (flat panel display), for example.

  In the FPD manufacturing process, there is a process of subjecting a target object such as an LCD (liquid crystal display) substrate to a predetermined plasma process such as an etching process or a film forming process. As a plasma processing apparatus that performs these steps, for example, a plasma processing apparatus that uses inductively coupled plasma (ICP) has attracted attention because it can generate high-density plasma. In this inductively coupled plasma processing apparatus, for example, a processing container is divided into upper and lower parts by a dielectric member, a substrate mounting table is provided in a lower processing space, and a radio frequency (RF) antenna is provided in the upper space. The inductively coupled plasma is formed in the processing space by supplying high frequency power to the antenna, and the processing gas supplied into the processing space is converted into plasma, thereby performing a predetermined plasma processing. Has been.

  As an antenna used in such an inductively coupled plasma processing apparatus, a spiral antenna is generally used in which an antenna wire is circularly wound in a plane. In the case of a large object to be processed, since the impedance of the antenna becomes large, a plurality of spiral antennas are used in combination. However, the glass substrate for the FPD substrate is becoming larger and larger, so that the length of the spiral antenna per one becomes longer, so that the impedance is increased, the high-frequency current is reduced accordingly, and high-density plasma may not be obtained. .

  In order to reduce the impedance, there are methods to increase the number of antenna branches and shorten the spiral antenna per antenna, or insert a capacitor at the end or middle of the antenna. In this case, however, the antenna structure is complicated. Therefore, handling becomes difficult, and the adjustment work of the antenna potential in the surface direction of the object to be processed becomes complicated. As a result, it is difficult to obtain plasma with high uniformity.

  For this reason, the present inventors have studied a configuration in which the antenna has a linear shape and the length of the antenna is shortened, thereby reducing the impedance. However, in order to construct a large antenna using a linear antenna, it is necessary to arrange a plurality of antennas. In this case, for example, as shown in FIG. 27, a plurality of antennas 11 having the same length are simply arranged in parallel to each other. The antennas 11 are arranged at predetermined intervals, both ends of each antenna 11 are connected to the conductive wires 12 and 13, and one of the conductive wires 12 is connected to a high frequency power supply unit 14 having a high frequency power supply and a matching unit, and the other In the configuration in which the conductive wire 13 is grounded, since the impedance of the path from the feeding point to the grounding point via each antenna 11 is different among the antennas 11, the magnitudes of currents flowing through the antennas 11 are different. It becomes difficult to generate plasma with high uniformity in the body surface direction.

  On the other hand, Patent Document 1 describes a configuration that includes a planar coil 34 in which eight linear metal conductor elements 51 to 58 are arranged in parallel to each other in an apparatus for generating inductively coupled plasma using a linear antenna. ing. Of these elements 51 to 58, the two central elements 54 and 55 have the same electrical length to the terminals 62 and 64 connected to the cables 67 and 72, respectively.

  However, also in this apparatus, since the change in the electrical length of the path from the cable 67 to the cable 72 via the elements 51 to 58 increases toward the outside of the planar coil 34, as a result, the planar coil 34. It is impossible to obtain a uniform impedance in the plane. In addition, this apparatus is intended to process a liquid crystal display having a planar rectangular structure with a side of 75 cm × 85 cm, for example, and the length of each of the conductor elements 51 to 58 is derived from the high frequency source 38. By setting to about 1.41 m which is about 1/16 of the wavelength (22.53 m) of the frequency (13.56 MHz), current and voltage fluctuations in each of the conductor elements 51 to 58 are prevented from becoming large.

  However, in recent years, there is an increasing trend toward larger substrates, and a larger glass substrate having a side of about 2 m may be processed. However, the length of the metal conductor elements 51 to 58 of Patent Document 1 is such a size of glass. It is difficult to perform highly uniform plasma processing on the substrate. Moreover, since the impedance will increase if the metal conductor elements 51 to 58 are made longer than 2 m, it is difficult to solve the problem of the present invention from this point.

JP-T-2001-511945 (FIG. 2)

  The present invention has been made under such circumstances, and it is an object of the present invention to increase the impedance of an antenna in an apparatus that generates inductively coupled plasma using an antenna and performs plasma processing on an object to be processed. It is another object of the present invention to provide a plasma processing apparatus capable of controlling the electric field distribution in the surface direction of the object to be processed and thereby adjusting the plasma density distribution.

For this reason, the plasma processing apparatus of the present invention generates an induction electric field in the processing container supplied with the processing gas, converts the processing gas into plasma, and plasmas the target object mounted on the mounting table in the processing container. In a plasma processing apparatus that performs processing,
An antenna including a plurality of linear antenna members which are provided outside the processing atmosphere so as to face the mounting table via the processing atmosphere, each having the same length and arranged in parallel to each other;
A high-frequency power supply for supplying high-frequency power to the antenna;
A power supply side conductive path for connecting one end side of the antenna to the high frequency power supply unit;
A ground-side conductive path for connecting the other end of the antenna to a ground point;
A capacitor for adjusting the potential distribution for adjusting the potential distribution of the antenna, provided on at least one of the power source side conductive path and the ground side conductive path,
The impedance of each high-frequency path from the high-frequency power supply unit to the ground point through each antenna member is set to be equal to each other.

The plasma processing apparatus of the present invention generates an induction electric field in a processing container supplied with a processing gas, converts the processing gas into plasma, and performs plasma processing on a target object placed on a mounting table in the processing container. In the plasma processing apparatus for performing
An antenna including a plurality of linear antenna members which are provided outside the processing atmosphere so as to face the mounting table via the processing atmosphere, each having the same length and arranged in parallel to each other;
A high-frequency power supply for supplying high-frequency power to the antenna;
A power supply side conductive path for connecting one end side of the antenna to the high frequency power supply unit;
A ground-side conductive path for connecting the other end of the antenna to a ground point;
A capacitor for adjusting a potential distribution for adjusting a potential distribution of the antenna, provided on at least one of the power supply side conductive path and the ground side conductive path;
An impedance adjusting capacitor provided on at least one of the power supply side conductive path and the ground side conductive path, for adjusting the impedance of a high frequency path from the high frequency power supply section to the ground point via each antenna member; It is characterized by providing.

  The interval between the antenna members may be configured to be adjustable. In this case, for example, one end side and the other end side of the antenna member may be connected to a moving unit that is movable in the arrangement direction of the antenna members. .

  Further, for example, a plurality of linear antenna members each having the same length may form a segment that is adjacent to each other and connected in parallel to each other, and a plurality of the segments may be arranged, where the segments are even numbers. The power source side conductive path and the ground side conductive path are lines that determine the combination of tournaments by connecting adjacent segments so that the physical lengths of the high frequency paths are equal between the segments. Wiring in a staircase pattern is preferable. Furthermore, it is preferable that the arrangement intervals of the antenna members are equal in any segment.

Furthermore, the antenna is provided between a plurality of dense portion regions in which a plurality of antenna members are arranged at a first interval, and between the dense portion regions. And a sparse part region arranged at a large second interval. Here, the first interval may be an interval between antenna members constituting the segment, and the second interval may be an interval between adjacent segments. The interval between the segments is configured to be adjustable, for example. Further, one end and the other end of the segment are connected to a moving unit that is movable in the arrangement direction of the segments, for example.
Furthermore, a dielectric window member provided between the mounting table and the antenna for defining the processing atmosphere is provided, and the dielectric window member includes a plurality of plates provided to face the mounting table. And a plurality of partition portions provided so as to be orthogonal to the antenna member along the length direction of the dielectric member in order to support the dielectric member. It may be configured.

  Here, a processing gas chamber is formed inside the partition portion, and a gas supply hole communicating with the processing gas chamber is formed on the lower surface of the partition portion to supply the processing gas to the processing container. It is preferable. Each of the plurality of partition portions is provided so as to be suspended from the ceiling portion of the processing container by a suspension support portion. Inside the suspension support portion, a processing gas communicating with the processing gas chamber of the partition frame portion is provided. It is preferable that a flow path is formed. Furthermore, the capacitor for adjusting the potential distribution is for adjusting the impedance so that the potential at the central portion in the length direction of the antenna member becomes zero.

  According to the present invention, in an apparatus that generates inductively coupled plasma using an antenna and performs plasma processing on an object to be processed, the antenna is configured by arranging linear antenna members having the same length. The increase in the impedance of the antenna member can be suppressed, and high-density plasma can be generated. According to the first aspect of the present invention, since the impedances of the high-frequency paths from the high-frequency power supply unit to the grounding point through the antenna members are set to be equal to each other, The uniformity of the electric field is improved, so that plasma with high uniformity can be generated, and plasma processing with high in-plane uniformity can be performed on the object to be processed.

  Further, according to the invention of claim 2, since the impedance adjustment capacitor can be used to adjust the impedance of the high-frequency path separately for the antenna member, the degree of automatic adjustment of the impedance of the high-frequency path is increased. For example, when the uniformity of the electric field in the surface direction of the object to be processed is increased, or when a large number of antenna members are provided, the electric field distribution is adjusted to change the electric field distribution between the inside and the outside in the arrangement direction of the antenna members. As a result, it is possible to improve the uniformity of the plasma processing on the object to be processed.

It is a longitudinal cross-sectional view which shows the plasma processing apparatus which concerns on one embodiment of this invention. It is a schematic perspective view which shows a part of said plasma processing apparatus. It is the top view which shows the antenna and dielectric window member which are provided in the said plasma processing apparatus, and sectional drawing of a dielectric window member. It is the top view which shows the antenna and dielectric material window member which are provided in the said plasma processing apparatus, and the connection figure of a conductive path. FIG. 4 is a characteristic diagram showing a relationship between an antenna potential and a position on a high frequency path, and a characteristic diagram showing a relationship between a plasma density and a position on the high frequency path. FIG. 4 is a characteristic diagram showing a relationship between an antenna potential and a position on a high frequency path, and a characteristic diagram showing a relationship between a plasma density and a position on the high frequency path. It is a characteristic view which shows the time change of the electric potential of an antenna. It is a characteristic view which shows the relationship between the arrangement method of an antenna member, and a plasma density. It is a top view which shows the other structural example of an antenna. It is a top view which shows the other example of an antenna. It is a perspective view which shows the other example of an antenna. It is a perspective view which shows the detail of the antenna member which comprises the said antenna. It is the schematic which showed the conductive path of the said antenna It is explanatory drawing which shows the relationship between arrangement | positioning of the said antenna member, and the plasma density distribution formed. It is explanatory drawing which shows the relationship between arrangement | positioning of the said antenna member, and the plasma density distribution formed. It is explanatory drawing which shows the relationship between arrangement | positioning of the said antenna member, and the plasma density distribution formed. It is explanatory drawing which shows the relationship between arrangement | positioning of the said antenna member, and the plasma density distribution formed. It is explanatory drawing which shows the relationship between arrangement | positioning of the said antenna member, and the plasma density distribution formed. It is a perspective view which shows the other example of an antenna. It is the schematic which showed the conductive path of the said antenna It is the top view and side view which show other example of an antenna. It is a schematic block diagram of the plasma processing apparatus containing the said antenna. It is explanatory drawing which shows an example of the recipe of the said plasma processing apparatus. It is a graph which shows distribution of the ashing rate of an evaluation test. It is a graph which shows distribution of the ashing rate of an evaluation test. It is a graph which shows distribution of the ashing rate of an evaluation test. It is a top view which shows the connection relation with the high frequency power supply part in the conventional linear antenna member.

Hereinafter, embodiments of the plasma processing apparatus of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of the plasma processing apparatus. In FIG. 1, reference numeral 2 denotes a processing container which is airtightly configured in, for example, a rectangular tube shape and grounded. The processing container 2 is made of a conductive material such as aluminum, and the inside of the dielectric window member 3 that is transparent to high frequency is hermetically divided into upper and lower portions, and the upper side of the dielectric window member 3 has an antenna chamber 21, The lower side is configured as a plasma generation chamber 22. A mounting table 27 for mounting a glass substrate G, which is a substrate, is provided inside the plasma generation chamber 22. As the glass substrate G, for example, a square glass substrate formed in a rectangular shape with a side of 2 m for FPD manufacture is used.

  The mounting table 27 is surrounded by an insulating member 28 on the side periphery and the peripheral side of the bottom, and is supported by the insulating member 28 while being insulated from the bottom wall of the processing vessel 2. ing. The mounting table 27 is connected to a bias high-frequency power supply unit 29 including a bias high-frequency power source and a matching device for supplying high-frequency power for biasing, for example, high-frequency power of 3.2 MHz, to the mounting table 27. Has been. In addition, the mounting table 27 incorporates a lifting pin (not shown) for transferring the glass substrate G to / from an external transfer means.

The dielectric window member 3 is a substantially plate-like body provided to face the mounting table 27 so as to constitute a ceiling portion of the plasma generation chamber 22 in order to define a processing atmosphere. A beam portion 31 made of a metal material and a plate-like dielectric member 32 whose side portions are supported by the beam portion 31 are provided. The dielectric member 32 is made of ceramics such as quartz or aluminum oxide (Al ₂ O ₃ ). Further, when the plasma treatment is performed on the glass substrate G, the pressure inside the plasma generation chamber 22 is set to a vacuum state and a predetermined strength is required, so that the thickness is set to about 30 mm, for example.

  As shown in the schematic perspective view of FIG. 2 and the plan view of FIG. 3, the beam portion 31 protrudes inward from the side wall of the processing container 2 and forms an outer frame portion 33 constituting the bottom portion of the antenna chamber 21, and the outer frame. A plurality of, for example, four partition portions 34 extending in parallel with each other in the Y direction in the drawing are provided inside the portion 33. By the partition portion 34, five divided regions parallel to the Y direction are formed inside the outer frame portion 33, and the dielectric member 32 is disposed in each of the divided regions. As shown in FIG. 1, for example, a step portion 35 for supporting the dielectric member 32 is formed in the outer frame portion 33 and the partition portion 34, and the dielectric member 32 is also engaged with the step portion 35. The step portion 36 is formed, and the dielectric member 32 is fitted into the beam portion 31 to constitute the dielectric window member 3.

  Such a dielectric window member 3 is placed in a processing container so that the dielectric window member 3 is horizontal in a state where the dielectric window member 3 is suspended from the ceiling portion of the processing container 2 by a suspension support part 4 extending in the Z direction in FIG. 2 is provided. The suspension support portion 4 has a processing gas flow passage 41 formed therein, and has one end connected to the upper surface of the partition portion 34 and the other end connected to the ceiling portion 20 of the processing vessel 2.

Further, as shown in the AA ′ cross-sectional view of the dielectric window member 3 in FIG. 3B, the suspension support portion 4 extends along the length direction (Y direction in the drawing) inside the partition portion 34. A processing gas chamber 42 is formed so as to communicate with the flow passage 41, and a number of gas supply holes 43 are formed in the lower surface of the partition portion 34 at predetermined intervals along the length direction thereof. Yes.
Further, a gas flow path 44 is formed in the ceiling portion 20 of the processing container 2 so as to communicate with the flow path 41 of the suspension support section 4, and a processing gas supply system 45 is connected to the gas flow path 44. Has been. The processing gas supply system 45 includes a gas supply path 45a connected to the gas flow path 44, a flow rate adjusting unit 45b, and a processing gas supply source 45c. As described above, the dielectric window member 3 also serves as a gas supply means for supplying the processing gas into the plasma generation chamber 22, and is supplied from the processing gas supply system 45 to the partition portion 34 via the suspension support portion 4. The processing gas is supplied into the plasma generation chamber 22 through the gas supply hole 43 on the lower surface of the partition part 34.

  In the antenna chamber 21 thus formed by the dielectric window member 3, linear antenna members 51 are arranged in a plane in the vicinity of the dielectric window member 3 so as to face the dielectric window member 3. An antenna 5 is provided. The antenna 5 is configured by arranging a plurality of linear antenna members 51 each having the same length in parallel to each other and arranging a plurality of segments 52 connected in parallel to each other in parallel. . In this example, the antenna member 51 is arranged to extend in the X direction in the drawing so as to be orthogonal to the partition portion 34 of the dielectric window member 3. In the drawing, the antenna member 51 is represented by a single black line in order to avoid confusion in the drawing.

The segment 52 of this example has a plurality of antenna members 51 having the same diameter and the same physical length, for example, four antenna members 51 arranged in parallel to each other at equal intervals, in the length direction (X direction). Both end sides are connected by an antenna member 50 extending in the Y direction in the drawing, and the antenna members 51 are connected in parallel to each other.
And the antenna 5 is arranged an even number of segments 52, the segments 52 are provided in ^the 2 ⁿ example 2 ^two in this example (4). In these segments 52 (52A to 52D), the antenna members 51 of the segments 52 adjacent to each other are provided in parallel to each other, and the segments 52 adjacent to each other than the interval L1 between the antenna members 51 constituting one segment 52. The intervals L2 are arranged so as to be larger.

  As a result, the antenna 5 includes a dense region 52 (segment 52) in which a plurality of antenna members 51 are arranged closely at a first interval, and a sparse portion in which a plurality of antenna members 51 are arranged at a second interval. Regions 53 (between adjacent segments 52) are alternately provided in the Y direction. And the suspension support part 4 of the said dielectric material window member 3 is provided in the said sparse part area | region 53 between the said adjacent segments 52 so that it may not interfere with the many antenna members 51 arranged.

  As shown in FIG. 2, the segment 52 includes a horizontal region 54 extending in the X direction so as to face the mounting table 27, and both the horizontal regions 54 in the length direction of the segment 52 (the X direction). The outer region 55, that is, both end portions in the length direction of the segment 52, for example, stand vertically on the upper side. As shown in FIGS. 1 to 3, the horizontal region 54 of the segment 52 is set to a size that covers the length in the X direction of the glass substrate G placed on the placement table 27. The segments 52 are arranged over the entire processing container 2 so as to cover the length of the glass substrate G in the Y direction. In this example, the X-direction length central portion of the plasma generation chamber 22 is aligned with the X-direction length central portion of the glass substrate G placed on the mounting table 27, and the horizontal region of the segment 52 The dimensions and installation positions of the plasma generation chamber 22, the mounting table 27, and the segment 52 are set so as to align with the central portion in the length direction in 54.

  One end of the antenna 5 is connected to the antenna 5 through a power supply side conductive path 61. The high frequency power for generating inductively coupled plasma, for example, high frequency power having a frequency of 13.56 MHz is supplied to the antenna 5. Are connected to a high-frequency power supply unit 6 for generating plasma. Here, as shown in FIGS. 2 and 4, in the power source side conductive path 61, the electrical length of the path from the connection portion with each segment 52 to the high frequency power source portion 6 becomes equal for each segment 52. Is set to Here, the electrical length is equal means that the impedance of the conductive path 61 from the high frequency power supply unit 6 to the connection portion of each segment 52 is equal, and the physical length of the conductive path 61 is equal. In addition, even if the physical lengths are different, the cross-sectional area of the conductive path 61 is different, and as a result, the impedance of the conductive path 61 from the high-frequency power supply unit 6 to the connecting portion becomes equal, or as described later The case where the impedance is adjusted to include the element for adjusting the impedance is also included.

  In this example, the power supply-side conductive path 61 is set so that the physical lengths from the connection portion to each segment 52 to the high-frequency power supply portion 6 are equal. Specifically, referring to FIG. 2 and FIG. 4, the power source side conductive path 61 includes segments 52 </ b> A and 52 </ b> B adjacent to each other from the one end side in the arrangement direction (Y direction in the drawing) of the antenna members 51 in the first stage. Next, the adjacent segments 52C and 52D are connected by the first-stage conductive path 61b. The intermediate points of the first-stage conductive paths 61a and 61b are connected by the second-stage conductive path 61c, and the intermediate point of the second-stage conductive path 61c and the high-frequency power supply unit 6 are connected by the termination conductive path 61d. Configured to be connected.

  The other end of the antenna 5 is connected to the ground by a ground-side conductive path 62, and a capacitance variable capacitor 7 serving as a capacitor for adjusting the potential distribution is provided between the antenna 5 and the ground point. As shown in FIGS. 2 and 4, the ground-side conductive path 62 is set so that the electrical length from the connection portion to each segment 52 to the variable capacitance capacitor 7 is equal to each segment 52. Has been. In this example, the ground-side conductive path 62 is set so that the physical length from the connection portion with each segment 52 to the variable capacitance capacitor 7 is equal.

  That is, for example, as shown in FIGS. 2 and 4, the ground-side conductive path 62 includes segments 52 </ b> A and 52 </ b> B adjacent to each other from the one end side in the arrangement direction (Y direction in the drawing) of the antenna members 51. Next, the segments 52C and 52D adjacent to each other are connected by the first-stage conductive path 62b. The intermediate points of the first-stage conductive paths 62a and 62b are connected by a second-stage conductive path 62c, and the intermediate point of the second-stage conductive path 62c and the capacitance variable capacitor 7 are connected by the conductive path 62d. Configured to be connected. Further, since the physical length to the variable capacitor 7 is equal, the physical length of the conductive path 62 connecting each segment 52 and the ground point is also equal. Thus, in this example, the electrical lengths (impedances) of the high-frequency paths are equal to each other by aligning the physical lengths of the high-frequency paths from the high-frequency power supply unit 6 to the ground point in the segments 52A to 52D. It is set to be. More specifically, the high-frequency path refers to a path that passes through each segment from the downstream side of the matching unit in the high-frequency power supply unit 6 for generating plasma to reach the grounding point.

  Here, as shown in FIG. 2, the power supply side conductive paths 61a to 61c and the ground side conductive paths 62a to 62c include a horizontal conductive path and an upright conductive path. The adjacent segments 52 are connected to each other so that the electrical lengths of the high-frequency paths are equal to each other so as to determine the combination of tournaments.

  The variable capacitance capacitor 7 is provided between the junction point of each ground side conductive path 62 and the ground point in the terminal conductive path 62d, and adjusts the capacitance to adjust the impedance of the antenna 5, thereby adjusting the antenna 5's impedance. This is for adjusting the potential distribution in the length direction. The adjustment of the potential distribution will be described with reference to FIGS. FIG. 5A is a configuration diagram when the variable capacitor 7 is not provided. In this case, the potential distribution in the length direction (X direction in the drawing) of the antenna 5 at a certain time is shown in FIG. It goes up as shown.

  On the other hand, when the variable capacitance capacitor 7 is provided, the temporal change in potential at the position P1 on the outlet side of the high frequency power supply unit 6 and the position P2 on the inlet side of the variable capacitance capacitor 7 in FIG. As shown in FIG. 6B, the phase is shifted by 90 degrees from each other, so that the distribution of the potential Vp (high frequency peak potential) at a certain moment in the length direction of the antenna 5 is as shown in FIG. That is, since the potential at the position P2 becomes negative according to the capacitance of the variable capacitance capacitor 7, the potential distribution from the position P1 to the position P2 has a zero point on the way. Therefore, the zero point position of the potential Vp can be freely set in the length direction of the antenna 5 by adjusting the capacitance of the variable capacitance capacitor 7. In this example, the zero point position is zero at the center position P3 in the length direction of the antenna 5. It is adjusted so that the point is located. By adjusting the potential distribution in the length direction of the antenna 5 in this way, the plasma density in the length direction of the antenna can be controlled.

Returning to FIG. 1, the processing container 2 is provided with an opening 23 on the side wall of the processing container 2 so that the glass substrate G can be transferred into and out of the plasma generation chamber 22 of the processing container 2 by a gate valve 24. In addition, an exhaust passage 25 is connected to the bottom of the exhaust passage 25, and the other end side of the exhaust passage 25 is connected to a vacuum pump 26 serving as a vacuum exhaust means via an exhaust amount adjusting unit 26a.
The plasma processing apparatus is configured to be controlled by a control unit. This control unit is composed of a computer, for example, and includes a CPU, a program, and a memory. In the program, a command (each step) is incorporated so that a control signal is sent from the control unit to each part of the plasma processing apparatus and a predetermined plasma process is performed. This program is stored in a storage unit such as a computer storage medium such as a flexible disk, a compact disk, a hard disk, or an MO (magneto-optical disk) and installed in the control unit.

  Next, the operation of the above embodiment will be described. First, the gate valve 24 is opened, and the glass substrate G is carried into the plasma generation chamber 22 from the opening 23 by an external transfer means (not shown), and is placed on the mounting table 27 via a lift pin (not shown). Next, while supplying the processing gas from the processing gas supply system 45 into the plasma generation chamber 22, the inside of the plasma generation chamber 22 is evacuated to a predetermined degree of vacuum by the vacuum pump 26 through the exhaust passage 25. The antenna chamber 21 is set to an atmospheric atmosphere.

  Next, high frequency power of, for example, 13.56 MHz is supplied from the high frequency power supply unit 6 to the antenna 5. As a result, an induction electric field is generated around the antenna 5, and the processing gas in the processing container 2 is turned into plasma (activated) by the energy of the electric field to generate plasma. Then, a high frequency power of 3.2 MHz, for example, is supplied from the bias high frequency power supply unit 29 to the mounting table 27, whereby ions in the plasma are drawn toward the mounting table 27, and the glass substrate G is etched.

  Here, the four segments 52 made of the antenna member 51 are connected to each other as shown in the combination diagram of the tournament with respect to the high-frequency power supply point and the grounding point as described above. Since the impedances of the high-frequency paths are equal, when the processing container 2 is viewed in the Y direction (arrangement direction of the antennas 5), the potential of each segment 52 becomes the same potential. The segment 52 has a plurality of linear antenna members 51, in this example, four antenna members 51. More specifically, the outer two antenna members 51 and the inner two antenna members 51 have a path length. Are different within the segment 52. Therefore, each segment 52 has a slight potential distribution, not the same potential when viewed in the arrangement direction, but the pattern of this potential distribution is aligned between the segments 52.

  If the arrangement interval of the antenna members 51 is the same over the entire antenna 5, the plasma density has a mountain-shaped distribution with a high center and low ends as shown in FIG. That is, the plasma density distribution in which the plasma density is highest on the lower side of the antenna member 51 provided in the central portion among all the antenna members 51 and gradually decreases from the antenna member 51 toward the outside. It becomes. For this reason, in the whole antenna 5, the difference in height of the plasma density becomes large, and the in-plane uniformity of the plasma density is lowered.

  On the other hand, in the present embodiment, the dense region 52 and the sparse region 53 are alternately formed by increasing the interval L2 between the adjacent segments 52 to be larger than the interval L1 between the antenna members 51 in the segment 52. Therefore, as shown in FIG. 8A, the plasma density has a mountain-shaped distribution for each segment 52. Therefore, the plasma density distribution along the surface direction of the object to be processed is uniform. It will be expensive. That is, in the dense region 52, the plasma density increases at a position corresponding to the central antenna member 51, but the change in plasma density is small. Since the dense region 52 and the sparse region 53 are alternately arranged in the arrangement direction, a plasma having a small density change is continuously formed in the arrangement direction. Uniformity is improved.

  Then, regarding the length direction of the antenna 5, as shown in FIG. 6B, the potential of the central portion in the length direction of the antenna member 51 becomes zero, and the potential distribution is relative to this zero point. It becomes symmetrical. In this case, the capacitive coupling is increased at the periphery of the antenna member 51, the inductive coupling is small, and the potential distribution is symmetrical with respect to the central portion in the length direction of the antenna member 51. Therefore, the plasma density distribution is shown in FIG. As shown, the result is a mountain-shaped distribution with a higher plasma density in the center.

On the other hand, in the configuration in which the capacitor is not provided, as shown in FIG. 5C, the plasma density on the grounding point side where the potential Vp is low is high and the plasma density on the high frequency power supply unit 6 side is low, Since the plasma density on the one side in the length direction of the antenna member 51 is high and the plasma density on the other side is low, the uniformity is lowered.
From the above, in the processing container 2, both the X direction (the length direction of the antenna member 51) and the Y direction (the arrangement direction of the antenna members 51) are along the surface direction of the object to be processed (X , In the Y plane), the uniformity of the electric potential distribution is high, so that the uniformity of the electric field is improved. For this reason, in-plane uniformity of the plasma density is increased, and plasma processing with high uniformity is performed within the surface of the object to be processed.

In such a plasma processing apparatus, since the antenna 5 is configured using the linear antenna member 51, the length of the antenna member 51 is shorter than that of the spiral antenna, and the impedance can be reduced. For this reason, compared with the case where a spiral antenna is used, the antenna potential can be easily suppressed.
Further, as described above, the impedance of each segment 52 is made uniform, the potential distribution is adjusted using the variable capacitor 7 so that the potential Vp of the central portion in the length direction of the antenna member 51 becomes zero, the antenna member By alternately forming dense portion regions 52 and sparse portion regions 53 having different arrangement intervals of 51, plasma with high uniformity is generated in the arrangement direction and the length direction of the antenna members 51 in the processing container 2. Therefore, plasma processing with high in-plane uniformity can be performed on the object to be processed. Furthermore, by connecting each segment 52 to the high-frequency power supply point and the grounding point as shown in the combined diagram of the tournament, the impedance of each segment 52 can be made uniform with a simple configuration, which is effective. .

  Further, in the present invention, since the partition portion 34 of the dielectric window member 3 is provided so as to be orthogonal to the antenna member 51 of the antenna 5, generation of induced current in the partition portion 34 is suppressed, and induction from the antenna 5 is performed. The electric field is smoothly transmitted to the plasma generation chamber 22 while suppressing unnecessary attenuation. In addition, a plurality of partition portions 34 are provided to form a plurality of divided regions, and the dielectric member 32 is disposed in each of the divided regions. Therefore, the dielectric member 32 provided in one divided region can be reduced in size. Can be The periphery of the miniaturized dielectric member 32 is supported by the beam portion 31 including the partition portion 34 and the outer frame portion 33, so that the space between the plasma generation chamber 22 in a vacuum atmosphere and the antenna chamber 21 in an atmospheric atmosphere is reduced. A sufficient strength can be ensured when airtightly partitioning. Furthermore, since the processing gas is supplied to the plasma generation chamber 22 through the partition portion 34 of the dielectric window member 3, and the dielectric window member 3 also serves as the processing gas supply means, the constituent members of the plasma processing apparatus are reduced. In addition, the apparatus can be simplified, and the manufacturing cost can be reduced.

Next, another configuration example of the antenna will be described with reference to FIG. The antenna 81 in the configuration of FIG. 9A has ²ⁿ segments 82, which in this example are 2 ³ segments, each consisting of two antenna members 80 having the same diameter and the same length extending in parallel with each other. (8 pieces). In this example, four antenna members 80 constituting two segments 82 are arranged at equal intervals from each other at an interval L1 to form a dense region 82 in which the antenna members 80 are closely arranged, and two segments 82 are formed. Between the two adjacent segments 82, a sparse part region 85 is formed in which the antenna members 80 are arranged at intervals L2 larger than the intervals L1 and the antenna members 80 are sparsely arranged. Then, each segment 82 is connected to each other by a power supply side conductive path 83 and a ground side conductive path 84 with respect to a high frequency power supply point and a ground point which are the output ends of the high frequency power supply unit 6 as shown in a combined diagram of a tournament. Accordingly, the physical lengths of the paths from the high-frequency power supply unit 6 to the ground point in each segment 82 are set to be equal to each other.

Further, the antenna 86 in the configuration of FIG. 9B has 2 ⁿ segments 88, each of which is composed of three antenna members 87 that are linearly parallel to each other and have the same physical length, in this example 2 ^2. It is the structure provided, and is comprised similarly to the above-mentioned antenna 5 except the number of the antenna members 87 differing.

  Furthermore, in the present invention, as shown in FIG. 10, a variable capacitance capacitor for impedance adjustment may be provided on the power supply conductive path side. In the antenna 9 of this example, for example, four segments 91A to 91D are arranged in the Y direction. On the power feeding side of the antenna 9, the two outer segments 91A and 91D are connected to each other by a power supply side conductive path 92a. A variable capacitance capacitor 93A for impedance adjustment is provided between the high-frequency power supply unit 6 and the junction between the conductive path 92a and the conductive path 92b, and is connected to the high-frequency power supply unit 6 through the conductive path 92b. Further, the inner two segments 91B and 91C are connected to each other by a power supply side conductive path 92a, and are connected to the high frequency power supply unit 6 through a conductive path 92d, and a junction point between the conductive path 92c and the conductive path 92d and a high frequency A variable capacitance capacitor 93B for adjusting impedance is provided between the power supply units 6.

  On the other hand, on the ground side of the antenna 9, the two outer segments 91A and 91D are connected by a ground side conductive path 93a and grounded via a conductive path 93b, and a junction between the conductive path 93a and the conductive path 93b. And a grounding point is provided with a fixed capacitor 94A for adjusting the potential distribution. The two inner segments 91B and 91C are connected to each other by a ground-side conductive path 93c and grounded via a conductive path 93d, and between the junction point of the conductive path 93c and the conductive path 93d and the ground point. Is provided with a fixed capacitor 94B for adjusting the potential distribution.

  In this example, the variable capacitance capacitors 93A and 93B include the impedance of the high-frequency path from the high-frequency power supply unit 6 to the ground point through the inner segments 91B and 91C, and the outer segments 91A and 91D. Used to change the impedance of the high frequency path. For example, by adjusting the capacitances of the variable capacitance capacitors 93A and 93B so that the impedance of the high-frequency path through the outer segments 91A and 91D is larger than the impedance of the high-frequency path through the inner segments 91B and 91C, The high-frequency current flowing through the inner segments 91B and 91C is made larger than the high-frequency current flowing through the outer segments 91A and 91D, and the plasma density of the inner segments 91B and 91C is increased with respect to the outer segments 91A and 91D. The in-plane distribution of plasma density can be controlled.

  Further, for example, by adjusting the variable capacitance capacitors 93A and 93B so that the impedance of the high-frequency path through the outer segments 91A and 91D is smaller than the impedance of the high-frequency path through the inner segments 91B and 91C, The in-plane distribution of the plasma density may be adjusted so that the plasma density of the inner segments 91B and 91C is smaller than that of the outer segments 91A and 91D.

  In this way, by adjusting the impedances of the high-frequency paths through the outer segments 91A and 91D and the inner segments 91B and 91C by the variable capacitance capacitors 93A and 93B, the inner segments 91B and 91C in the surface direction of the substrate are adjusted. Since the plasma density can be finely controlled between the plasma generated by the above and the plasma generated by the outer segments 91A and 91D, the in-plane distribution (uniformity) can be further finely adjusted. Here, the variable capacitance capacitors 93A and 93B are provided in both the inner segments 91B and 91C and the outer segments 91A and 91D in this example, but may be provided in either one.

By providing the variable capacitor for impedance adjustment in this way, the impedance of the high-frequency path can be adjusted by dividing into segments, so the degree of automatic adjustment of the impedance of the high-frequency path is increased. Thereby, for example, the uniformity of the electric field in the surface direction of the glass substrate G can be improved, or the electric field distribution can be adjusted to change the electric field distribution between the inner side and the outer side of the segment arrangement direction. It is possible to improve the uniformity of the plasma treatment for the object to be processed.
Also, as shown in FIG. 10, if segments are connected as shown in the tournament diagram and a plurality of segments are connected to a common variable capacitance capacitor, a single variable capacitance capacitor can be used for a plurality of segments at the same time. The impedance of the high frequency path can be adjusted, and the adjustment becomes easy.

Further, the capacitor for adjusting the potential distribution may be provided in the power supply side conductive path connecting the antenna and the high frequency power supply unit. Further, as the capacitor for adjusting the potential distribution, either a fixed capacitance capacitor or a variable capacitance capacitor may be used.
Furthermore, the antenna of the present invention may be provided so as to be embedded in the dielectric window member. Furthermore, the interval L2 between the adjacent segments is made narrower than the interval L1 between the antenna members in the same segment, and a sparse part region in which the antenna members are arranged sparsely is formed by the antenna member constituting the segment, You may make it form the dense part area | region where an antenna member is arranged closely by the antenna member of mutually adjacent segments. The plasma processing of the present invention can be applied to film formation processing, etching processing, resist film ashing processing, and the like.

  By the way, as described above, as the antenna used in the inductively coupled plasma processing apparatus, a spiral antenna in which an antenna wire is planarly wound in a ring shape is generally used as described above, but a large substrate is processed. In the case of the device, since the impedance of the antenna becomes large and high-density plasma may not be obtained, in order to prevent this, in each of the embodiments described above, each antenna has a linear shape, and the impedance per antenna Is suppressed. However, depending on the arrangement interval of the linear antenna members, it may be difficult to control the in-plane uniformity of the processing substrate. Therefore, an embodiment in which the antenna members can be changed to an arbitrary interval will be described below with reference to FIG. In this embodiment, an antenna 100 is provided instead of the antenna 5 in the antenna chamber 21 formed by the dielectric window member 3.

  The antenna 100 includes two antenna members 101 extending in a direction orthogonal to the partition portion 34 of the dielectric window member 3. Each antenna member 101 is provided in parallel to each other, is configured to have the same shape and the same length, and further, both end portions thereof form a bent portion 102 that is bent upward. As shown in FIG. 12, each bending region 102b is provided with a mounting hole 103 penetrating in the length direction of the antenna member 101.

  In the antenna chamber 21, taps 104 a and 104 b that extend horizontally perpendicular to the extending direction of the antenna member 101 are provided on both ends of the antenna member 101. Since the taps 104a and 104b are configured similarly, the tap 104a will be described as a representative. A large number of screw holes 105 into which the screws 106 are screwed to the respective taps 104a along the extending direction of the tap 104a. Is provided.

  The antenna member 101 can be detachably attached to the taps 104a and 104b by screwing (screwing) the screws 106 into the screw holes 105 of the taps 104a and 104b through the attachment holes 103 of the bent portion 102. By selecting the screw hole 105, the installation position of each antenna member 101 in the Y direction (direction orthogonal to the antenna member 101) and the interval between the antenna members 101 can be freely adjusted.

  A power supply side conductive path 111 and a ground side conductive path 112 are connected to one end side and the other end side of the antenna member 101 attached to the taps 104a and 104b, respectively. The power supply side conductive path 111 and the ground side conductive path 112 are bent and extended in the lateral direction after going upward, for example, like the power supply side conductive path 61 and the ground side conductive path 62 of FIG.

  FIG. 13 shows the antenna 100 as an electrically equivalent diagram. Referring to FIG. 13 as well, reference numerals 113 and 114 in FIG. 13 denote connection points between the antenna member 101 and the power supply side conductive path 111, and the antenna. Connection points between the member 101 and the ground side conductive path 112 are shown. The power supply-side conductive path 111 includes a first-stage power-supply-side conductive path 111a that connects the antenna members 101 to each other, and a second-stage power-supply-side conductive path that is connected to the high-frequency power supply unit 6 from an intermediate point of the conductive path 111a. 111b. Thus, the lengths of the conductive paths from the high frequency power supply unit 6 to each connection point 113 are configured to be equal, and thereby the impedances from the high frequency power supply unit 6 to each connection point 113 are set to be equal.

  The power supply side conductive path 112 is a first stage power supply side conductive path 112 a that connects the antenna members 101, and a second stage that connects the intermediate point of the conductive path 112 a and the grounding point via the variable capacitance capacitor 7. Power supply side conductive path 112b. In this way, the lengths of the conductive paths from the respective connection points 114 to the ground point are configured to be equal, whereby the impedances from the respective connection points 114 to the ground point of the antenna member 101 and the ground side conductive path 112 are equal to each other. Is set to Further, the impedances of the antenna members 101 are set to be equal to each other, and accordingly, the electrical lengths of the high-frequency paths constituted by the antenna members 101 are set to be equal to each other.

  In the antenna 100 described above, how the plasma density distribution 8 formed in the plasma generation chamber 22 changes every time the distance between the antenna members 101 is changed will be described with reference to FIGS. In each figure, the reference numeral (a) attached after the figure number shows an example of the layout of the arrangement of the antenna members 101 in the antenna chamber 21, and the reference numeral (b) after the figure number shows the same figure. The plasma density distribution 8 formed in the plasma generation chamber 22 when the number (a) layout is adopted is shown. In each example, the antenna member 101 is symmetrically positioned at an intermediate position of the antenna chamber 21 in the Y direction, and the intermediate position of the glass substrate G in the Y direction and the intermediate position of the antenna chamber in the Y direction overlap each other. In addition, the plasma density distribution 8 of each FIG. 14-18 (b) is shown based on the result confirmed by the below-mentioned evaluation test.

  First, the case where the antenna member 101 has the layout shown in FIG. 14A in which the antenna member 101 is installed at a relatively close distance in the central portion of the antenna chamber 21 will be described. Thus, when the distance between the antenna members 101 is short, the two antenna members 101 function as if they are one thick antenna member, and the two antenna members 101 are connected to each other as shown in FIG. An induction magnetic field 110 is formed so as to surround it as a book antenna member. The induction magnetic field 110 formed here has an effect of generating a magnetic field stronger than the induction magnetic field formed by one antenna member 110 when the antenna members 110 appear to be bundled.

  In the plasma generation chamber 22, the plasma density is highest at the central portion where the antenna member 101 is provided above, and gradually increases from the central portion toward the outside along the arrangement direction of the antenna members 101. This results in a plasma density distribution 8 in which the plasma density decreases. Incidentally, a chain line 80 in FIG. 14B shows a plasma density distribution formed when one of the two antenna members 101 is not provided and only the other one is provided. In this example, since the two antenna members 101 function as one antenna member 101 as described above, the plasma density distribution 8 is obtained when only one antenna member 101 indicated by the chain line is provided. The plasma density distribution is substantially the same. However, as compared with the case where only one antenna member 101 is provided, a strong induction magnetic field is formed as described above, so that the plasma generation chamber 22 is compared with the case where only one antenna member 101 is provided. The plasma density distribution 8 in the central part of becomes large.

  FIGS. 15 to 18 show the plasma density distribution 8 when the antenna member 101 is placed away from the central portion of the antenna chamber 21 as compared with FIG. 14, and thus the antenna member 101. Are relatively separated from each other, an induction magnetic field 110 is individually formed around each antenna member 101. The chain line 80 in each of FIGS. 15 to 18 (b) indicates the plasma density distribution formed when one antenna member 101 exists alone as in FIG. 14 (b). When only one 101 is provided, the plasma density distribution is high under the antenna member 101 as indicated by the chain line 80, and the plasma density decreases as the distance from the antenna member 101 increases in the lateral direction. Further, the plasma density distribution 8 formed in the plasma generation chamber 22 is a combination of the plasma density distributions formed for each of the antenna unit 101 materials.

  Then, as shown in FIGS. 15 to 18, the mounting position of the antenna member 101 is shifted toward the peripheral edge of the antenna chamber 21, and the plasma density formed in the plasma generation chamber 22 as the distance between the antenna members 101 increases. Regarding the distribution 8, the plasma density in the central portion in the generation chamber 22 decreases, whereas the plasma density in the peripheral portion increases. For example, in FIGS. 15A and 16A in which the antenna member 101 is provided relatively close to each other, as in the case of the layout of FIG. 14A, FIGS. As shown in FIG. 16 (b), the central portion side of the plasma generation chamber 22 has a higher density distribution than the peripheral portion side. In the layout of FIG. 17A in which the distance between the antenna members 101 is larger than the layout of FIGS. 15A and 16A, a substantially uniform plasma is generated in the plasma generation chamber 22 as shown in FIG. 17B. In the layout of FIG. 18A in which the density distribution 8 is formed and the antenna member 101 is further apart from the density distribution 8, the peripheral side of the plasma generation chamber 22 is compared to the central side as shown in FIG. 18B. High density distribution.

  In the antenna 100 that can change the distance between the antenna members 101 in this way, the plasma density distribution formed in each part in the plasma generation chamber 22 is controlled by adjusting the distance between the two antenna members 101 and performing processing. be able to. For example, the plasma density distribution in the plasma generation chamber 22 may change depending on the processing conditions such as the type of gas and the supply amount of the gas. When the processing conditions are changed in this way, the antenna member 101 in the antenna 100 is changed. This is advantageous because a highly uniform process can be performed on the glass substrate G.

  Moreover, when it is set as the structure which can change the position of an antenna member, as the number of the antenna members 101, it is not restricted to two pieces. FIG. 19 is a perspective view of the antenna 120 when the number of the antenna members 101 is four, and FIG. 20 shows the antenna 120 as an electrically equivalent diagram. In this antenna 120, the first and second antenna members 101 constitute one segment (dense area) 121, and the third and fourth antenna members constitute one segment 121 when viewed in the arrangement direction of the antenna members 101. is doing. 19 and 20, portions that are configured in the same manner as the antenna 100 are denoted by the same reference numerals.

  The antenna member 101 is connected to the high-frequency power supply unit 6 via the power supply side conductive path 123 and to the ground point via the ground side conductive path 124. In FIG. 20, 125 is a connection point between the power supply side conductive path 123 and each antenna member 101, and 126 in the figure is a connection point between the ground side conductive path 124 and each antenna member 101.

  The power supply side conductive path 123 and the ground side conductive path 124 are configured in a diagram shape that determines the combination of tournaments by connecting the segments 121 adjacent to each other as in the other embodiments. Specifically, in the power supply side conductive path 123, the second stage conductive path 123b connects between the intermediate points of the first stage conductive paths 123a that connect the antenna members 101 of the same segment 121 to each other. A third-stage conductive path 123c connects the intermediate point of the conductive path 123b and the high-frequency power supply unit 6. By wiring in this way, the lengths of the conductive paths from the high frequency power supply unit 6 to each antenna member 101 are made equal, and the respective impedances of the respective conductive paths are set to be equal.

  In the ground-side conductive path 124, the second-stage conductive path 124b connects the intermediate points of the first-stage conductive paths 124a that connect the antenna members 101 of the same segment 121 to each other. A third-stage conductive path 124c connects the middle point of the path 124b and the high-frequency power supply unit 6. By wiring in this way, the length of the conductive path from each antenna member 101 to the ground point is made equal, and the impedance of each conductive path is set equal. By configuring each conductive path in this way, the electrical lengths of the high-frequency paths are set to be equal to each other as in the above-described embodiments.

  Even in the antenna 120 configured as described above, the distance between the antenna members 101 constituting the same segment 121 and the distance between the antenna members 101 constituting different segments 121 can be freely adjusted, so that the antenna 120 is formed in the plasma generation chamber 22. The plasma density distribution can be controlled. Further, as described above, by bringing the antenna member 101 closer, the induction magnetic field to be formed can be strengthened to obtain a high etching rate, so that the position of the antenna member 101 is adjusted between different segments 121 and within the same segment 121. Thus, such a high etching rate can be obtained.

  Further, the distance between the antenna members may be automatically adjusted. FIGS. 21A and 21B show the plane and side surfaces of such an antenna 130, respectively. The antenna 130 will be described with a focus on differences from the antenna 100. Both ends of the two antenna members 101 are connected to the drive unit 131, respectively. For example, the drive unit 131 is configured to be movable in the antenna chamber 21 along a guide rail 132 extending in the arrangement direction of the antenna members 101. The upstream side of the variable capacitance capacitor 7 in the power supply side conductive path 111 and the ground side conductive path 112 is configured by flexible wiring so as not to hinder the movement of the antenna member 101.

  An example of the configuration of the control unit provided in the plasma processing apparatus including the antenna 130 will be described with reference to FIG. The control unit 140 in the figure includes a bus 141, and a CPU 142 and a recipe storage unit 143 are connected to the bus 141. The recipe storage unit 143 stores a plurality of processing recipes set with respect to the gas type to be supplied to the processing container 2, the gas flow rate, and the like, and each of these processing recipes includes setting of the interval of the antenna member 101.

For example, when the user selects a processing recipe via a selection unit (not shown) configured by a keyboard or the like, the selected processing recipe is read from the recipe storage unit 143 by the CPU 142. Then, a control signal corresponding to the read processing recipe is output from the control unit 140 to the driving unit 131 of the plasma processing apparatus. The drive unit 131 that has received the control signal moves as indicated by an arrow in FIG. 21A, and is controlled so that the interval of the antenna member 101 becomes the interval set in the selected processing recipe. The gas set in the selected processing recipe is supplied at the same flow rate set in the processing recipe, and processing is performed.

  In the plasma processing apparatus, when the substrate G is continuously transferred to the processing container 2, for example, the processing recipe is selected for each lot of the substrate G to control the distance between the antenna members 101. Further, as a processing recipe, as shown in FIG. 23, the interval of the antenna member 101 may be set to change according to the time zone of the process, and the antenna member 101 may be processed during processing of one substrate G. The plasma treatment may be performed by changing the interval.

  Thus, even when the antenna member moves, a capacitor for adjusting the impedance of each segment can be attached as shown in FIG.

(Evaluation test)
An evaluation test for examining a plasma density distribution was performed using a plasma processing apparatus including the antenna 100. The distance between the antenna members 101 is changed for each test, the plasma processing is performed on the substrate G coated with the photoresist, the formed plasma is observed, and the antenna arrangement direction on the substrate G after the processing is performed. The ashing rate of photoresist was investigated. As processing conditions for the substrate G, the pressure in the plasma generation chamber 22 was 10 mTorr, and the power supplied from the high-frequency power supply unit 6 was 2000 W.

  In the antenna chamber 21, when the distance from the center portion of the substrate to the end portion when viewed in the arrangement direction of the antenna members 101 is L, the distance between the antenna members 101 is about 1/3 L in the evaluation test 1 and the evaluation test. 2 was about 2 / 3L, evaluation test 3 was about L, evaluation test 4 was about 4 / 3L, and evaluation test 5 was about 2L. FIG. 14A to FIG. 19A described in the embodiment show the layout of the antenna member 101 in each of the evaluation tests 1 to 5. The measurement position of the ashing rate of each substrate G was an arbitrary position from the center of the substrate G toward the one end side and the other end side of the substrate G along the Y direction (arrangement direction of the antenna members).

  As an observation result of the plasma during processing on the substrate G, in the evaluation tests 1 and 2, the plasma was observed to be strong in the central portion of the plasma generation chamber 22 and weak in the peripheral portion. In the evaluation test 3, the plasma was observed in the central part of the plasma generation chamber 22 slightly stronger than the peripheral part, and in the evaluation test 4, the central part and the peripheral part were observed with high uniformity. In the evaluation test 5, plasma was weakly observed at the central portion of the plasma generation chamber 22 and strongly observed at the peripheral portion.

  Table 1 above shows the ashing rate measured at each part of the substrate G in the evaluation tests 1 to 5, and FIGS. 24A to 26E show the tables as graphs. As the measurement position, the center of the substrate is 0, and the distance from the center to the peripheral edge on one end and the other end of the substrate is shown. The sign of-is added to each. The higher the ashing rate, the higher the plasma density above it. In the evaluation tests 1 to 3, the distribution is such that a convex graph is drawn in which the ashing rate at the center of the substrate G is higher than the ashing rate at the periphery, and in the evaluation test 4, the ashing rate and the periphery of the center of the substrate G The ashing rate has a distribution that draws a flat graph with a substantially uniform ashing rate. In the evaluation test 5, the ashing rate at the peripheral portion is a concave graph distribution higher than the ashing rate at the central portion.

  From the results of the evaluation tests 1 to 5, it is shown that the plasma density distribution in the plasma generation chamber 22 can be controlled by controlling the distance between the antenna members 101, and the ashing rate in the plane of the substrate can be controlled. It was. In the evaluation test 1 in which the distance between the antenna members 101 is the shortest, the ashing rate at the center of the substrate below the antenna member 101 is particularly high, and the ashing on the lower side of the antenna member 101 in the other evaluation tests is performed. Higher than the rate. From this, it was shown that when the antenna member 101 is disposed close to the antenna member 101, the distribution of the plasma density around the antenna member 101 can be increased and a high ashing rate can be obtained. In the evaluation tests 1 to 5, the ashing rate of the photoresist was examined. Similarly, in the etching, the distance between the antenna members 101 is controlled to control the plasma density distribution in the plasma generation chamber 22 and the substrate. It is clear that the etching rate in the plane can be controlled. As mentioned above, although embodiment which can change between antenna members to arbitrary intervals was described, the antenna member of the above-mentioned embodiment was replaced with the segment which a plurality of antenna members connected in parallel, and between these segments was made into arbitrary intervals. It is good also as a structure which can be changed.

2 Processing container 21 Antenna chamber 22 Plasma generating chamber 3 Dielectric window member 31 Beam portion 32 Dielectric member 33 Outer frame portion 34 Partition portion 4 Suspension support portion 41 Flow path 42 Processing gas chamber 43 Gas supply hole 5, 100 Antenna 51 101 antenna member 52 segment 53 sparse area 54 horizontal area 6 high frequency power supply 61 power supply side conductive path 62 ground side conductive path 7, 71 variable capacitance capacitor 131 drive unit 140 control unit

Claims (15)

In a plasma processing apparatus that generates an induction electric field in a processing container supplied with a processing gas, converts the processing gas into plasma, and performs plasma processing on an object to be processed placed on a mounting table in the processing container.
An antenna including a plurality of linear antenna members which are provided outside the processing atmosphere so as to face the mounting table via the processing atmosphere, each having the same length and arranged in parallel to each other;
A high-frequency power supply for supplying high-frequency power to the antenna;
A power supply side conductive path for connecting one end side of the antenna to the high frequency power supply unit;
A ground-side conductive path for connecting the other end of the antenna to a ground point;
A capacitor for adjusting the potential distribution for adjusting the potential distribution of the antenna, provided on at least one of the power source side conductive path and the ground side conductive path,
A plasma processing apparatus, wherein impedances of each high-frequency path from the high-frequency power supply unit to the ground point via each antenna member are set to be equal to each other. In a plasma processing apparatus that generates an induction electric field in a processing container supplied with a processing gas, converts the processing gas into plasma, and performs plasma processing on an object to be processed placed on a mounting table in the processing container.
An antenna including a plurality of linear antenna members which are provided outside the processing atmosphere so as to face the mounting table via the processing atmosphere, each having the same length and arranged in parallel to each other;
A high-frequency power supply for supplying high-frequency power to the antenna;
A power supply side conductive path for connecting one end side of the antenna to the high frequency power supply unit;
A ground-side conductive path for connecting the other end of the antenna to a ground point;
A capacitor for adjusting a potential distribution for adjusting a potential distribution of the antenna, provided on at least one of the power supply side conductive path and the ground side conductive path;
An impedance adjusting capacitor provided on at least one of the power supply side conductive path and the ground side conductive path, for adjusting the impedance of the high frequency path from the high frequency power supply unit to the ground point via each antenna member; A plasma processing apparatus comprising:   The plasma processing apparatus according to claim 1, wherein an interval between the antenna members is configured to be adjustable.   The plasma processing apparatus according to claim 3, wherein one end side and the other end side of the antenna member are connected to a moving unit that is movable in the arrangement direction of the antenna members.   4. A plurality of linear antenna members each having an equal length form a segment formed adjacent to each other and connected in parallel to each other, and a plurality of the segments are arranged. The plasma processing apparatus according to claim 1.   An even number of the segments are arranged, and the power supply side conductive path and the ground side conductive path are connected to each other so that the physical lengths of the high-frequency paths are equal between the segments. 6. The plasma processing apparatus according to claim 5, wherein the plasma processing apparatus is wired in a staircase pattern to determine a combination.   The plasma processing apparatus according to claim 5, wherein the antenna members are arranged at equal intervals in any segment. The antenna is
A plurality of dense regions in which a plurality of antenna members are arranged at a first interval;
8. A sparse part region provided between the dense part regions, wherein a plurality of antenna members are arranged at a second interval larger than the first interval. The plasma processing apparatus according to any one of the above.   The plasma processing apparatus according to claim 8, wherein the first interval is an interval between antenna members constituting the segment, and the second interval is an interval between adjacent segments.   The plasma processing apparatus according to claim 5, wherein an interval between the segments is configured to be adjustable.   The plasma processing apparatus according to claim 10, wherein one end and the other end of the segment are connected to a moving unit that is movable in the arrangement direction of the segments. A dielectric window member provided between the mounting table and the antenna to define the processing atmosphere;
The dielectric window member includes a plurality of plate-like dielectric members provided to face the mounting table,
A plurality of partition portions provided so as to be orthogonal to the antenna member along a length direction of the dielectric member to support the dielectric member. The plasma processing apparatus according to any one of 11.   A processing gas chamber is formed inside the partition portion, and a gas supply hole communicating with the processing gas chamber is formed on the lower surface of the partition portion to supply a processing gas to the processing container. The plasma processing apparatus according to claim 12.   The plurality of partition portions are provided so as to be suspended from the ceiling portion of the processing container by suspension support portions, respectively, and the inside of the suspension support portions allows passage of processing gas communicating with the processing gas chamber of the partition frame portion. The plasma processing apparatus according to claim 13, wherein a flow path is formed. 15. The capacitor for adjusting the potential distribution is for adjusting impedance so that a potential at a central portion in the length direction of the antenna member becomes zero. The plasma processing apparatus as described in one.

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