TW201306671A - Antenna unit for inductively coupled plasma and inductively coupled plasma processing apparatus - Google Patents

Abstract

The present invention provides an antenna unit for inductively coupled plasma capable of performing plasma distribution control on the outer region of a rectangular substrate. The portion of antenna (13) of the antenna unit (50) that entirely forms the inductive electric field is constituted a rectangular plane corresponding to the rectangular substrate (G), and has a first antenna portion (13a) and a second antenna portion (13b) constituted by winding plural antenna wires into spiral shape; four corner portions of the rectangular plane are formed with the plural antenna wires of the first antenna portion (13a), and the four corner portions are combined at positions different from the rectangular plane; the central portions of the four edges of the rectangular plane are formed with the plural antenna wires of the second antenna portion (13b), and the central portion of the four edges are combined at positions different from the rectangular plane.

Description

Inductively coupled plasma antenna unit and inductively coupled plasma processing device

The present invention relates to an inductively coupled plasma antenna unit used for performing inductively coupled plasma processing on a rectangular substrate such as a glass substrate for manufacturing a flat panel display (FPD), and an inductively coupled plasma processing apparatus using the same.

In a manufacturing step of a flat panel display (FPD) such as a liquid crystal display (LCD), a plasma processing step of performing plasma etching, a film forming process, or the like on a rectangular rectangular substrate is used, and electricity is used for performing such plasma processing. Various plasma processing apparatuses such as a slurry etching apparatus and a plasma CVD film forming apparatus. As a plasma processing apparatus, a capacitive coupling plasma processing apparatus has been conventionally used, and recently, an Inductively Coupled Plasma (ICP) processing apparatus which has an excellent advantage, that is, a high-density plasma can be obtained at a high degree of vacuum. Attention.

Inductively coupled plasma processing apparatus, the top wall of the processing container accommodating the substrate to be processed is composed of a dielectric window, and a high frequency antenna is disposed on the upper side of the dielectric window, and the processing gas is supplied to the processing container and the high The frequency antenna supplies high-frequency power, and an inductively coupled plasma is generated in the processing container, and the inductively coupled plasma is used to perform a predetermined plasma treatment on the substrate to be processed. As the high-frequency antenna, a planar coil antenna that forms a predetermined pattern in a planar shape is often used.

An inductively coupled plasma processing apparatus using a planar coil antenna generates plasma in a space directly below a planar antenna in a processing container, at which time, The electric field strength at each position directly below the line is proportional to the distribution of the high plasma density region and the low plasma density region, and thus the pattern shape of the planar antenna is an important factor determining the plasma density distribution.

In the case where the rectangular substrate for FPD manufacturing is subjected to plasma treatment, the planar antenna is a shape in which the overall shape corresponds to a rectangular substrate. For example, Patent Document 1 discloses that a planar antenna having a rectangular shape is formed as a whole, and the planar antenna has an outer antenna portion and an inner antenna portion; the outer antenna portion constitutes an outer portion, and an arrangement region thereof is formed in a frame shape; and the inner antenna portion is The inner portion is formed in the outer antenna portion, and the arrangement region is also formed in a frame shape.

In the planar antenna disclosed in Patent Document 1, the outer antenna portion and the inner antenna portion are arranged such that the positions of the four antenna wires are sequentially shifted by 90° to form a substantially frame-like spiral shape. In general, since the plasma diffuses isotropically, it has a property of being axisymmetric. Even in the case of using such a frame antenna, since the plasma of the corner portion tends to be weak, the number of corners is rounded. It is set to be larger than the central portion of the side (see the second drawing of Patent Document 1).

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2007-311182

However, recently, finer control of the plasma distribution at the corners and the center of the side of the outer side region of the rectangular substrate is required, and the technique according to Patent Document 1 may have a corresponding difficulty. For example, in the outer region of the rectangular substrate, it is possible to reduce the etching rate at the central portion of the side portion and increase the etching rate of the corner portion, etc., and it is difficult to cope with such a requirement according to the technique of Patent Document 1.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an inductively coupled plasma antenna unit and an inductively coupled plasma processing apparatus capable of performing plasma distribution control of a region outside a rectangular substrate.

In order to solve the above problems, a first aspect of the present invention provides an antenna unit for an inductively coupled plasma, which is an inductively coupled plasma antenna unit having a coil-shaped antenna for use in an inductively coupled plasma processing apparatus. An inductively coupled plasma for generating a plasma treatment on a rectangular substrate is formed in the processing chamber; wherein the antenna forms a rectangular plane corresponding to the rectangular substrate and forms a plurality of antenna lines. a first antenna unit and a second antenna unit that are formed in a spiral shape; the plurality of antenna lines of the first antenna unit are four corner portions forming the rectangular plane, and are different from the rectangular plane The four corner portions are coupled to each other; the plurality of antenna lines of the second antenna portion are central portions of the four sides forming the rectangular plane, and the four sides are different from the rectangular plane. The central portion is coupled; the first antenna portion and the second antenna portion are independently supplied with high frequency power.

In the above-described first aspect, the plurality of antenna lines constituting the first antenna unit may have a first planar portion forming the corner portion and a portion between the first planar portions. a first three-dimensional portion that is in a retracted state above the first planar portion; and the plurality of antenna lines that constitute the second antenna portion have a second planar portion that forms a central portion of the side and a second planar portion The second portion is a retracted state above the second planar portion. Further, the first antenna unit and the second antenna unit are positions of four antenna lines, respectively. It is configured by winding in a 90° step by step.

According to a second aspect of the present invention, there is provided an antenna unit for an inductively coupled plasma, which is an inductively coupled plasma antenna unit having a plurality of coil-shaped antennas, wherein a portion of the plurality of antennas forming an induced electric field constitutes a rectangular plane And arranging the antennas to be concentric, and the antennas are used to generate an inductively coupled plasma for performing plasma processing on the rectangular substrate in a processing chamber of the inductively coupled plasma processing apparatus; At least the outermost circumference of the antenna, the rectangular plane corresponds to the rectangular substrate, and has a first antenna portion and a second antenna portion configured by winding a plurality of antenna wires in a spiral shape; and the plurality of first antenna portions The root antenna line is formed by forming four corner portions of the rectangular plane and combining the four corner portions at positions different from the rectangular plane; and the plurality of antenna lines of the second antenna portion are formed a central portion of four sides of the rectangular plane, and a central portion of the four sides is joined at a position different from the rectangular plane; the first antenna portion and the second antenna Independently supplied high frequency power.

According to a third aspect of the present invention, there is provided an inductively coupled plasma processing apparatus comprising: a processing chamber, a mounting table, a processing gas supply system, an exhaust system, an inductively coupled plasma antenna unit, and a power supply mechanism; a chamber for accommodating a rectangular substrate and performing a plasma treatment; the mounting table is a rectangular substrate placed in the processing chamber; the processing gas supply system supplies a processing gas to the processing chamber; the exhaust system is The processing chamber performs exhausting; the inductively coupled plasma antenna unit has a coil-shaped antenna, and the antenna is used to generate a moment in the processing chamber The inductively coupled plasma is subjected to plasma processing; the power supply mechanism supplies high frequency power to the antenna; and the antenna, which forms an induced electric field, is a rectangular plane corresponding to the rectangular substrate, and has a a plurality of antennas are wound into a spiral shape to form a first antenna portion and a second antenna portion; and the plurality of antenna wires of the first antenna portion are formed by four corner portions of the rectangular plane, and The four corner portions are joined at different positions on the rectangular plane; the plurality of antenna lines of the second antenna portion are central portions that form four sides of the rectangular plane, and are different from the rectangular plane. The central portion of the four sides is coupled to each other, and the power feeding mechanism supplies the high-frequency power independently to the first antenna portion and the second antenna portion.

According to a fourth aspect of the present invention, there is provided an inductively coupled plasma processing apparatus comprising: a processing chamber, a mounting table, a processing gas supply system, an exhaust system, an inductively coupled plasma antenna unit, and a power supply mechanism; a chamber for accommodating a rectangular substrate and performing a plasma treatment; the mounting table is a rectangular substrate placed in the processing chamber; the processing gas supply system supplies a processing gas to the processing chamber; the exhaust system is Exhausting in the processing chamber; the inductively coupled plasma antenna unit has a plurality of coil-shaped antennas for generating inductively coupled plasma for plasma processing of the rectangular substrate in the processing chamber; The mechanism supplies high-frequency power to the antenna; the plurality of antennas form a rectangular electric plane, and the antennas are arranged in a concentric shape, and at least the outermost circumference of the plurality of antennas has a rectangular plane Corresponding to the aforementioned rectangular substrate, and will be complex a plurality of antennas are wound in a spiral shape to form a first antenna portion and a second antenna portion; and the plurality of antenna wires of the first antenna portion are four corner portions forming the rectangular flat surface, and The four corner portions are joined at different positions on the rectangular plane; the plurality of antenna lines of the second antenna portion are central portions that form four sides of the rectangular plane, and are different from the rectangular plane. The central portion of the four sides is coupled to each other, and the power feeding mechanism supplies the high frequency power independently to the first antenna portion and the second antenna portion.

According to the present invention, the entire portion of the antenna forming the induced electric field is a rectangular plane corresponding to the rectangular substrate, and the plurality of antenna lines of the first antenna portion are four corner portions forming a rectangular plane, and are in a rectangular shape. Four corners are combined at different positions of the plane; a plurality of antenna lines of the second antenna portion are central portions of four sides forming a rectangular plane, and the central portions of the four sides are combined at positions different from the rectangular plane. Since the high-frequency power is independently supplied to the first antenna portion and the second antenna portion, the electric field intensity of the central portion of the corner portion and the side portion can be controlled, and the plasma distribution of the outer region of the rectangular substrate can be controlled.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a cross-sectional view showing an inductively coupled plasma processing apparatus according to an embodiment of the present invention. This apparatus is used for etching of a metal film, an ITO film, an oxide film, and the like, and a plasma cleaning process of a photoresist film when a thin film transistor is formed on a rectangular substrate, for example, a FPD glass substrate. As the FPD, for example, liquid crystal Display, electroluminescence (EL) display, plasma display panel (PDP), etc.

This plasma processing apparatus has a square tubular and airtight main body container 1 made of a conductive material, for example, an aluminum which is anodized on the inner wall surface. The main body container 1 is assembled to be decomposable and grounded through the grounding wire 1a. The main body container 1 is vertically divided into an antenna chamber 3 and a processing chamber 4 by a dielectric wall 2. Therefore, the dielectric body wall 2 is the top wall constituting the processing chamber 4. The dielectric body wall 2 is made of ceramic such as Al ₂ O ₃ , quartz or the like.

A shower housing 11 for supplying a processing gas is embedded in a lower portion of the dielectric body wall 2. The shower housing 11 is provided in a cross shape, and has a structure in which the dielectric body wall 2 is supported from below. The shower housing 11 for supporting the dielectric body wall 2 is suspended from the top of the main body container 1 by a plurality of suspension devices (not shown).

The shower housing 11 is made of a conductive material, and is preferably made of a metal such as aluminum which is anodized on the inner surface, thereby preventing corrosion of the treated gas and causing contamination. A horizontally extending gas flow path 12 is formed in the shower housing 11, and the gas flow path 12 communicates with a plurality of gas discharge holes 12a extending downward. On the other hand, at the center of the upper surface of the dielectric body wall 2, the gas supply pipe 20a is provided in communication with the gas flow path 12. The gas supply pipe 20a is connected from the top of the main body container 1 to the outside thereof, and is connected to a process gas supply system 20 including a processing gas supply source, a valve system, and the like. Therefore, in the plasma processing, the processing gas supplied from the processing gas supply system 20 is supplied into the shower housing 11 through the gas supply pipe 20a, and the gas discharge hole 12a from the lower side thereof faces the processing chamber 4. Spit inside.

A support frame 5 projecting inward is provided between the side wall 3a of the antenna chamber 3 of the main body container 1 and the side wall 4a of the processing chamber 4, and the dielectric body wall 2 is placed on the support frame 5.

An antenna unit 50 including a high frequency (RF) antenna 13 is disposed in the antenna room 3. By supplying high frequency power to the high frequency antenna 13, an induced electric field can be formed in the processing chamber 4, and the processing gas supplied from the shower housing 11 can be plasmad by the induced electric field. Further details of the antenna unit 50 will be described later.

Below the inside of the processing chamber 4, a mounting table 23 on which the rectangular substrate G is placed is provided so as to face the high-frequency antenna 13 via the dielectric body wall 2. The mounting table 23 is made of a conductive material such as aluminum whose surface is anodized. The rectangular substrate G placed on the mounting table 23 is sucked and held by an electrostatic chuck (not shown).

The mounting table 23 is housed in the insulator frame 24 and supported by a hollow pillar 25 . The pillar 25 is inserted through the bottom of the main body container 1 so as to maintain the airtight state, and is supported by an elevating mechanism (not shown) disposed outside the main body container 1. When the rectangular substrate G is carried in and out, the elevating mechanism is used. The mounting table 23 is driven in the vertical direction. Further, between the insulator frame 24 for accommodating the mounting table 23 and the bottom of the main body container 1, a bellows 26 capable of hermetically surrounding the support post 25 is disposed, whereby the processing container 4 can be secured even if the mounting table 23 moves up and down. Air tightness inside. Further, the side wall 4a of the processing chamber 4 is provided with a loading/unloading port 27a for carrying in and out the rectangular substrate G, and a gate valve 27 for opening and closing the rectangular substrate G.

Through the power supply line 25a disposed in the hollow pillar 25, through the integration The high frequency power supply 29 is connected to the mounting table 23. In the high-frequency power source 29, high-frequency power for bias voltage, for example, high-frequency power having a frequency of 6 MHz is applied to the mounting table 23 in the plasma processing. The ions in the plasma generated in the processing chamber 4 are efficiently sucked by the rectangular substrate G by the high-frequency power for the bias.

Further, the mounting table 23 is provided with a temperature control means and a temperature sensor (not shown) including a heating means such as a ceramic heater for controlling the temperature of the rectangular substrate G, a refrigerant flow path, and the like. The piping and wiring of the mechanisms and members are led out to the outside of the main body container 1 through the hollow pillars 25.

At the bottom of the processing chamber 4, an exhaust device 30 including a vacuum pump or the like is connected to the exhaust pipe 31. The processing chamber 4 is exhausted by the exhaust device 30, and the inside of the processing chamber 4 is set and maintained in a predetermined vacuum atmosphere (for example, 1.33 Pa) in the plasma processing.

A cooling space (not shown) is formed on the back side of the rectangular substrate G placed on the mounting table 23, and a He gas flow path 41 for supplying a constant pressure of heat, that is, He gas, is provided. By supplying the heat transfer gas to the back side of the rectangular substrate G as described above, it is possible to avoid temperature rise and temperature change of the rectangular substrate G under vacuum.

Each component of the plasma processing apparatus is controlled by a control unit 80 that is connected to a microprocessor (computer). Further, the control unit 80 is connected to a user interface 81 including a keyboard for inputting an operation such as command input for the operator to manage the plasma processing apparatus, and visualizing the operation state of the plasma processing apparatus. Display the display, etc. Further, the control unit 80 is connected to the storage unit 82, and the memory unit 82 stores a control program for realizing various processes executed by the plasma processing device under the control of the control unit 80, in order to comply with the processing conditions. A program for executing processing of each component of the plasma processing apparatus, that is, a processing menu. The processing menu is a memory medium stored in the storage unit 82. The memory medium can be a hard disk built in a computer, a semiconductor memory, or a portable person such as a CDROM, a DVD, or a flash memory. Further, the menu may be appropriately transmitted from another device, for example, through a dedicated line. Further, if necessary, an arbitrary processing menu is called from the storage unit 82 by the instruction from the user interface 81, and the control unit 80 is executed, whereby the plasma processing apparatus performs the desired operation under the control of the control unit 80. deal with.

Next, the antenna unit 50 described above will be described in detail.

Fig. 2 is a plan view showing an example of an antenna unit used in an antenna unit of the apparatus of Fig. 1; and Fig. 3 is a plan view showing a first antenna unit of a radio-frequency antenna used in the antenna unit of Fig. 2; A perspective view showing a first antenna portion of a radio-frequency antenna used in the antenna unit of FIG. 2; and a fifth view showing a second antenna portion of the radio-frequency antenna used in the antenna unit of FIG. 2; FIG. A perspective view showing a second antenna portion of the radio-frequency antenna used in the antenna unit of Fig. 2 is shown.

As shown in FIG. 2, the high-frequency antenna 13 of the antenna unit 50 forms an induced electric field (which contributes to plasma generation), and the entire portion facing the dielectric body wall 2 has a rectangular shape corresponding to the rectangular substrate G ( The frame-like plane has a first antenna portion 13a and a second antenna portion 13b which are formed by winding a plurality of antennas in a spiral shape. The antenna line of the first antenna portion 13a is formed Four corners of a rectangular plane, and four corners are joined at a position different from the rectangular plane. Further, the antenna line of the second antenna portion 13b is a central portion of the four sides forming a rectangular flat surface, and the central portions of the four sides are joined at positions different from the rectangular flat surface.

The power supply to the first antenna portion 13a is transmitted through the four terminals 22a and the power supply line 69 provided around the gas supply pipe 20a, and the power supply to the second antenna portion 13b is transmitted through the gas supply pipe 20a. The terminal 22b and the power supply line 79 are performed.

As shown in Fig. 1, the first power feeding member 16a is connected to each of the four terminals 22a of the first antenna portion 13a, and the second power feeding member 16b is connected to each of the four terminals 22b of the second antenna portion 13b (in the first figure). Only one is displayed). The four first power feeding members 16a are connected to the power supply line 19a, and the four second power feeding members 16b are connected to the power supply line 19b. The power supply line 19a is connected to the integrator 14a and the first high frequency power supply 15a, and the power supply line 19b is connected to the integrator 14b and the second high frequency power supply 15b. By the first high-frequency power supply 15a and the second high-frequency power supply 15b, for example, high-frequency power of a frequency of 13.56 MHz can be independently supplied from the first antenna portion 13a and the second antenna portion 13b, and the control unit 80 can be independently used. The current values supplied thereto are independently controlled.

The high-frequency antenna 13 is disposed so as to be separated from the dielectric body wall 2 by a separator 17 formed of an insulating member, and its arrangement region corresponds to the rectangular substrate G.

The first antenna portion 13a of the high-frequency antenna 13 forming the four corner portions of the rectangular flat surface is wound by four antenna lines 61, 62, 63, 64 as shown in Figs. 3 and 4 . Wrapped to form a planar shape in a frame-like multiple (four Heavy) antenna. Specifically, the positions of the antenna wires 61, 62, 63, 64 are sequentially shifted by 90°, and the portions forming the four corners of the rectangular plane facing the dielectric wall 2 are formed into a plane. The portions 61a, 62a, 63a, and 64a; the portions between the plane portions 61a, 62a, 63a, and 64a are three-dimensional portions 61b, 62b, 63b, and 64b that are located at positions different from the rectangular plane and are retracted upward. . The three-dimensional portions 61b, 62b, 63b, and 64b are disposed at positions that do not contribute to plasma generation.

Further, the second antenna portion 13b constituting the central portion of the four sides of the rectangular plane of the radio-frequency antenna 13 is four antenna lines 71, 72, and 73 as shown in Figs. 5 and 6 . 74 is wound to form a multiple (quadruple) antenna having a planar shape in a frame shape. Specifically, the positions of the antenna wires 71, 72, 73, 74 are sequentially shifted by 90°, and the portions forming the central portions of the four sides facing the rectangular plane of the dielectric body wall 2 are formed. The flat portions 71a, 72a, 73a, and 74a, and the portions between the flat portions 71a, 72a, 73a, and 74a are the three-dimensional portions 71b, 72b, and 73b that are retracted to a position different from the rectangular plane. 74b. The three-dimensional portions 71b, 72b, 73b, and 74b are disposed at positions that do not contribute to plasma generation.

The antenna wires 61, 62, 63, 64 of the first antenna portion 13a are supplied with power through the four terminals 22a and the power supply line 69, and the antenna wires 71, 72, 73, 74 of the second antenna portion 13b are used. Power is supplied through the four terminals 22b and the power supply line 79.

Next, the processing operation when the plasma etching process is performed on the rectangular substrate G using the inductively coupled plasma processing apparatus of the above configuration will be described.

First, in the state where the gate valve 27 is opened, by the transport mechanism (not shown) The rectangular substrate G is carried into the processing chamber 4, and placed on the mounting surface of the mounting table 23, and then the rectangular substrate G is fixed to the mounting table 23 by an electrostatic chuck (not shown). Next, in the processing chamber 4, the processing gas supplied from the processing gas supply system 20 is discharged from the gas discharge hole 12a of the shower housing 11 into the processing chamber 4, and is passed through the exhaust pipe 31 through the exhaust device 30. Vacuum evacuation is performed in the processing chamber 4, whereby the processing chamber is maintained at a pressure atmosphere of, for example, about 0.66 to 26.6 Pa.

In addition, in the cooling space on the back side of the rectangular substrate G, in order to avoid temperature rise and temperature change of the rectangular substrate G, He gas which is a heat transfer gas is supplied through the He gas flow path 41.

Then, high frequency electric power of, for example, 13.56 MHz is applied to the first antenna portion 13a constituting the corner portion of the radio-frequency antenna 13 and the second portion constituting the center portion of the side portion from the first high-frequency power source 15a and the second high-frequency power source 15b. The antenna portion 13b passes through the dielectric body wall 2 to form an induced electric field corresponding to the rectangular substrate G in the processing chamber 4. The processing gas is plasma-formed in the processing chamber 4 by the induced electric field thus formed, and a uniform and high-density inductively coupled plasma is generated in a region corresponding to the rectangular substrate G.

As a result, the portion of the radio-frequency antenna 13 that faces the dielectric wall 2 is composed of the first antenna portion 13a and the second antenna portion 13b, and the entire shape is a frame shape corresponding to the rectangular substrate G. Therefore, the rectangular substrate G can be used. The whole supply of plasma.

As described above, in the related art, the antenna having a frame-shaped structure has a tendency to weaken the plasma at the corners. Therefore, in Patent Document 1, the number of windings of the antenna for the corner is set to be the center of the side. More and seek plasma uniformity In recent years, it has been demanded to finely control the distribution of the plasma at the corners of the outer region of the rectangular substrate and the center of the side, and it is difficult to cope with the technique of Patent Document 1.

Therefore, in the present embodiment, the high-frequency antenna 13 forms an induced electric field (helps plasma generation), and the entire portion facing the dielectric body wall 2 constitutes a rectangular (frame-like) plane corresponding to the rectangular substrate G. Further, the first antenna portion 13a that forms the four corners of the antenna line and the second antenna portion 13b that forms the central portion of the four sides of the antenna line are provided to the first antenna portion 13a and the second antenna portion 13b. The high-frequency power from the first high-frequency power source 15a and the second high-frequency power source 15b are independently supplied, and the current value flowing through the control unit 80 is controlled, so that the corner portion of the outer region of the rectangular substrate G can be The plasma distribution in the center of the side is finely controlled to perform the desired plasma treatment.

In addition, the first antenna portion 13a is a multiplexed (quadruple) antenna in which the positions of the four antenna wires 61, 62, 63, and 64 are sequentially shifted by 90° to form a frame shape. The position corresponding to each of the corner portions becomes a flat portion 61a, 62a, 63a, 64a which contributes to the plasma formation facing the dielectric body wall 2, and the portion between the flat portions 61a, 62a, 63a, 64a becomes The three antenna portions 13b, 62b, 63b, and 64b are retracted to the upper portion, and the second antenna portion 13b is also wound by sequentially shifting the positions of the four antenna wires 71, 72, 73, and 74 by 90°. On the other hand, a plurality of (quadruple) antennas having a planar shape in a frame shape are formed at the positions corresponding to the central portion of the four sides, and are flat portions 71a, 72a, and 73a that contribute to plasma generation while facing the dielectric body wall 2. 74a, the portion between the plane portions 71a, 72a, 73a, 74a becomes helpless The slurry is generated and retracted to the upper three-dimensional portions 71b, 72b, 73b, and 74b. The first antenna portion 13a and the second antenna portion 13b are basically in the form of a conventional multiple antenna, and are simply combined with each other. Independent plasma distribution control of the corners and the central portion of the sides can be achieved.

In the above example, the frame antenna-shaped high-frequency antenna 13 is formed by a total of two antenna portions corresponding to the first antenna portion 13a corresponding to the corner portion and the second antenna portion 13b corresponding to the center of the side, and can be independently performed. Current control; however, it may be constituted by three or more antenna sections, and it is also possible to perform current control independently of them. For example, the center of the side may be divided into two antenna portions including the second antenna portion and the third antenna portion. Further, the center of the side is divided into three parts, and the middle portion is set as the second antenna portion, and the intermediate portion is interposed therebetween. The both side portions may be set as the third antenna portion. Other configurations that are permitted in this manner can also be employed.

Further, in addition to the current value control by connecting different high-frequency power sources to the first antenna unit 13a and the second antenna unit 13b, as shown in Fig. 7, the high-frequency power from the high-frequency power source 15 can be passed via After the power splitter 83 is divided, the first antenna portion 13a and the second antenna portion 13b are supplied with high-frequency power via the integrators 14a and 14b, and current values of the first antenna portion 13a and the second antenna portion 13b are controlled. In this way, a high-frequency power supply can be used, which can reduce the burden on the device. Further, as shown in Fig. 8, the first antenna portion 13a and the second antenna portion 13b may be formed by providing an impedance adjusting mechanism 84 including a variable capacitor or the like in any of the power supply lines 19a and 19b. Current value control. In this case, as long as one high frequency power source 15 and one integrator 14 are provided, the burden on the device can be further reduced.

Next, other examples of the antenna unit will be described.

Fig. 9 is a plan view showing another example of the antenna unit. When the rectangular substrate G is enlarged and the frame-shaped high-frequency antenna 13 has a rectangular shape, the plasma power in the central portion is weak, and it is difficult to form a uniform plasma. Then, in the present example, as shown in FIG. 9, the outer antenna is the inner antenna 113 in which the radio antenna 13 is disposed, and the inner antenna 113 having a rectangular frame shape concentrically arranged inside, thereby constituting the antenna unit 50a. Thus, the plasma density of the inner region corresponding to the central portion of the rectangular substrate G is increased to make the plasma density more uniform. In this example, the inner antenna 113 has the same structure as the above-described high frequency antenna 13. In other words, the entire planar shape of the portion facing the dielectric body wall 2 has a frame shape, and has a first antenna portion 113a constituting the four corner portions thereof and a second antenna portion 113b constituting a central portion of each side. Further, similarly to the radio-frequency antenna 13 constituting the outer antenna, the current value of the first antenna portion 113a and the current value of the second antenna portion 113b are independently controlled. Thereby, the plasma density distribution of the corner portion and the central portion of the inner antenna 113 can be adjusted to make the plasma density more uniform.

However, the most prominent portion of the plasma density at the center and the corner is the outer peripheral portion. As long as the outer antenna is constructed using the high-frequency antenna 13, the plasma density distribution can be sufficiently controlled, so the inner antenna does not have to be used. The same configuration as that of the high-frequency antenna 13 is not particularly limited as long as the outer antenna can independently control the current values of the corner portion and the center portion of the side. For example, as shown in FIG. 10, the antenna unit 50b having the inner antenna 123 may be used. In other words, the inner antenna 123 is a multiplexed (quadruple) antenna in which four antenna lines 91, 92, 93, and 94 are wound to form a spiral shape. Specifically, the positions of the antenna wires 91, 92, 93, and 94 are sequentially shifted by 90° to be wound. The arrangement area of the antenna wires is substantially frame-shaped, and the number of windings of the corner portion having a tendency to weaken the plasma is larger than the number of windings at the center portion of the side. In the illustrated example, the number of corner turns is three, and the number of turns at the center of the side is two. Further, a crank portion (curved portion) 98 is formed in each antenna wire, and a plasma generating region surrounded by the outer contour line and the inner contour line of the inner antenna 123 is linearly symmetric with respect to the center line of the two sides penetrating the opposing direction. (Mirror-symmetric), so that the plasma generation region can face the rectangular substrate G. That is, it is possible to generate a plasma in a state of being opposed to the rectangular substrate G, and it is possible to improve the uniformity of the plasma.

Further, as the inner antenna, a general multiplex antenna as in the above-described Patent Document 1 can be used.

Furthermore, it is also possible to arrange three or more frame antennas concentrically. In this case, at least the outermost antenna must be independently controlled in current at least in the two portions of the corner and the center of the side.

Further, as shown in Fig. 11, the intermediate antenna 133 having the same structure as that of the first antenna portion 13a can be disposed between the outer antenna 13 and the inner antenna 123 to constitute the antenna unit 50c. According to this configuration, only the corner portion of the region between the outer antenna 13 and the inner antenna 123 can be reinforced to perform so-called local plasma distribution control, and the controllability of the plasma distribution can be improved. Instead of the intermediate antenna 133, an intermediate antenna having the same structure as that of the second antenna portion 13b may be provided between the outer antenna 13 and the inner antenna 123 to perform local plasma distribution control. Further, instead of the intermediate antenna 133, an antenna similar to the outer antenna 13 may be provided. The antenna is composed of an antenna portion similar to the antenna portion 13a and an antenna portion similar to the antenna portion 13b. That is, the three-day sky consisting of the outer antenna, the middle antenna, and the inner antenna In the line, the outer antenna and the intermediate antenna employ the split antenna configuration disclosed in the present invention. According to this configuration, it is possible to realize a plasma processing apparatus which can perform uniform processing even in the case where the substrate to be processed becomes larger. The inner antenna is of course not limited to the structure of the inner antenna 123.

Further, the present invention is not limited to the above embodiment, and various modifications can be made. For example, the arrangement of the antenna wires for the antenna is not limited to the one described in the above embodiment, and the rectangular contour having at least the outer peripheral portion of the rectangular substrate is provided, and the portion corresponding to the outer circumference of the rectangular substrate has at least two regions. The current values of the regions are independently controlled, and are not particularly limited. Further, although the number of turns of the antenna wire is exemplified as 3, it is not limited thereto. In addition, the antenna is a quadruple antenna in which four antennas are wound by a wire to form a spiral, but it can also be composed of multiple antennas other than four.

Further, in the above embodiment, the top of the processing chamber is constituted by a dielectric body wall, and the antenna is disposed outside the processing chamber, that is, above the dielectric wall of the top; however, as long as the antenna and the plasma generating region can be It is also possible to isolate the dielectric wall, and it is also possible to adopt a configuration in which the antenna is disposed in the processing chamber.

Further, although the above embodiment has been described in the case where the present invention is applied to an etching apparatus, it can be applied to other plasma processing apparatuses such as CVD film formation. Further, although an example in which an FPD board is used as a rectangular substrate is shown, it can also be applied to a case where another rectangular substrate such as a solar cell is processed.

1‧‧‧ body container

2‧‧‧Dielectric wall (dielectric member)

3‧‧‧Antenna room

4‧‧‧Processing room

13‧‧‧High frequency antenna

13a‧‧‧1st antenna

13b‧‧‧2nd antenna

14‧‧‧ Integrator

15‧‧‧High frequency power supply

15a‧‧‧1st high frequency power supply

15b‧‧‧2nd high frequency power supply

16a, 16b‧‧‧Power supply components

19,19a,19b‧‧‧Power supply line

20‧‧‧Processing gas supply system

22a, 22b‧‧‧ terminals

23‧‧‧ mounting table

30‧‧‧Exhaust device

50, 50a, 50b, 50c‧‧‧ antenna unit

61,62,63,64,71,72,73,74,91,92,93,94‧‧‧ antenna lines

61a, 62a, 63a, 64a, 71a, 72a, 73a, 74a ‧ ‧ flat

61b, 62b, 63b, 64b, 71b, 72b, 73b, 74b‧‧‧3

69,79‧‧‧Power supply line

80‧‧‧Control Department

81‧‧‧User interface

82‧‧‧Memory Department

83‧‧‧Power splitter

84‧‧‧Impedance adjustment mechanism

98‧‧‧Bend

113,123‧‧‧Inside antenna

113a‧‧‧1st antenna

113b‧‧‧2nd antenna

133‧‧‧Intermediate antenna

G‧‧‧Rectangle substrate

Fig. 1 is a view showing an inductively coupled plasma portion of an embodiment of the present invention. A cross-sectional view of the device.

Fig. 2 is a plan view showing an example of an antenna unit used in the inductively coupled plasma processing apparatus of Fig. 1.

Fig. 3 is a plan view showing a first antenna portion of a radio-frequency antenna used in the antenna unit of Fig. 2;

Fig. 4 is a perspective view showing the first antenna portion of the radio-frequency antenna used in the antenna unit of Fig. 2;

Fig. 5 is a plan view showing a second antenna portion of the radio-frequency antenna used in the antenna unit of Fig. 2;

Fig. 6 is a perspective view showing a second antenna portion of the radio-frequency antenna used in the antenna unit of Fig. 2.

Fig. 7 shows another mode in which current control is performed individually for the first antenna portion and the second antenna portion.

Fig. 8 shows still another embodiment in which current control is performed individually for the first antenna portion and the second antenna portion.

Fig. 9 is a plan view showing an example of an antenna unit including an outer antenna and an inner antenna.

Fig. 10 is a plan view showing another example of an antenna unit including an outer antenna and an inner antenna.

Fig. 11 is a plan view showing an example of an antenna unit further including an intermediate antenna in addition to the outer antenna and the inner antenna.

13‧‧‧High frequency antenna

13a‧‧‧1st antenna

13b‧‧‧2nd antenna

20a‧‧‧ gas supply pipe

22a, 22b‧‧‧ terminals

69,79‧‧‧Power supply line

50‧‧‧Antenna unit

Claims (8)

An antenna unit for inductively coupled plasma is an inductively coupled plasma antenna unit having a coil-shaped antenna for generating a plasma treatment for a rectangular substrate in a processing chamber of an inductively coupled plasma processing apparatus a coupling plasma, wherein the antenna forms a rectangular planar plane corresponding to the rectangular substrate, and has a first antenna portion configured by winding a plurality of antennas in a spiral shape and a second antenna portion; the plurality of antenna lines of the first antenna portion are four corner portions forming the rectangular flat surface, and the four corner portions are joined at positions different from the rectangular plane; the second antenna The plurality of antenna wires of the antenna portion are central portions of the four sides forming the rectangular flat surface, and the central portions of the four sides are coupled at positions different from the rectangular plane; the first antenna portion and the second portion The antenna sections are each independently supplied with high frequency power. The inductively coupled plasma antenna unit according to the first aspect of the invention, wherein the plurality of antenna lines constituting the first antenna unit have a first planar portion forming the corner portion and forming the first portion a first three-dimensional portion that is in a retracted state above the first planar portion, and a plurality of antenna lines that form the second antenna portion: a second planar portion that forms a central portion of the side And forming the aforementioned second plane The second portion is a retracted state above the second planar portion. The inductively coupled plasma antenna unit according to the first or second aspect of the invention, wherein the first antenna portion and the second antenna portion are sequentially shifted by positions of four antenna lines. °The winding is configured. An inductively coupled plasma antenna unit is an inductively coupled plasma antenna unit having a plurality of coil-shaped antennas, wherein a part of the plurality of antennas forming an induced electric field constitutes a rectangular plane, and the antennas are configured Concentrically, the antennas are used to generate an inductively coupled plasma for performing plasma processing on a rectangular substrate in a processing chamber of the inductively coupled plasma processing apparatus; wherein at least the outermost circumference of the plurality of antennas is The rectangular planar surface corresponds to the rectangular substrate, and has a first antenna portion and a second antenna portion that are formed by winding a plurality of antenna wires in a spiral shape; and the plurality of antenna wires of the first antenna portion form the aforementioned Four corner portions of the rectangular plane are joined to each other at a position different from the rectangular plane; and the plurality of antenna lines of the second antenna portion are formed at the center of four sides of the rectangular plane And connecting the central portion of the four sides at a position different from the rectangular plane; the first antenna portion and the second antenna portion are independently supplied with a high frequency electric power. Inductively coupled plasma antenna as described in claim 4 In any one of the plurality of antennas, the one of the plurality of antennas has a plurality of antenna lines, and a part of the plurality of antennas is disposed in a desired portion to form an induced electric field forming portion, and the remaining portion is a backflow that does not form an induced electric field. unit. An inductively coupled plasma processing apparatus, comprising: a processing chamber, a mounting table, a processing gas supply system, an exhaust system, an antenna unit for inductively coupled plasma, and a power supply mechanism; the processing chamber is for housing a rectangular substrate And performing a plasma treatment; the mounting table is configured to mount a rectangular substrate in the processing chamber; the processing gas supply system supplies a processing gas to the processing chamber; and the exhaust system exhausts the processing chamber; The antenna unit for inductively coupled plasma has a coil-shaped antenna for generating an inductively coupled plasma for performing plasma processing on a rectangular substrate in the processing chamber; the power supply mechanism supplies high frequency power to the antenna; In the antenna, the entire portion forming the induced electric field is a rectangular flat surface corresponding to the rectangular substrate, and has a first antenna portion and a second antenna portion which are formed by winding a plurality of antenna wires in a spiral shape. a plurality of antenna lines of the antenna portion are four corner portions forming the rectangular plane, and are different from the rectangular plane Positioning the four corners; the plurality of antenna lines of the second antenna portion forming the rectangle a central portion of the four sides of the planar plane, and a central portion of the four sides is coupled to a position different from the rectangular plane; the power feeding mechanism independently supplies the first antenna portion and the second antenna portion with a high frequency electric power. An inductively coupled plasma processing apparatus, comprising: a processing chamber, a mounting table, a processing gas supply system, an exhaust system, an antenna unit for inductively coupled plasma, and a power supply mechanism; the processing chamber is for housing a rectangular substrate And performing a plasma treatment; the mounting table is configured to mount a rectangular substrate in the processing chamber; the processing gas supply system supplies a processing gas to the processing chamber; and the exhaust system exhausts the processing chamber; The antenna unit for inductively coupled plasma has a plurality of coil-shaped antennas for generating inductively coupled plasma for performing plasma processing on a rectangular substrate in the processing chamber; the power supply mechanism supplies high supply to the antenna a plurality of antennas, wherein a part of the plurality of antennas forming the induced electric field constitutes a rectangular plane, and the antennas are arranged concentrically, and a rectangular plane of at least the outermost circumference of the plurality of antennas corresponds to the rectangular substrate, and a plurality of antennas are wound in a spiral shape to form a first antenna portion and a second antenna portion; and the first antenna portion A plurality of antenna wires are formed in the four corners of a rectangular plane, and the four corners of the bonded portion with the rectangular plane different positions; The plurality of antenna wires of the second antenna portion are central portions that form four sides of the rectangular flat surface, and the central portions of the four sides are coupled at positions different from the rectangular planar surface. The power supply mechanism is The first antenna unit and the second antenna unit independently supply high-frequency power. The inductively coupled plasma processing apparatus according to claim 6 or 7, further comprising a control unit configured to control a current value flowing through the first antenna portion and a current flowing through the second antenna portion value.