KR20120136289A - Antenna unit for inductively coupled plasma and apparatus for inductively coupled plasma processing - Google Patents

Abstract

PURPOSE: An antenna unit for inductively coupled plasma and an apparatus for processing the inductively coupled plasma are provided to control electric field intensity of an edge portion and a central portion of a side by supplying high frequency power to a first antenna unit and second antenna unit, respectively. CONSTITUTION: A part forming an induced electric field of an antenna(13) comprises a rectangular shaped plane corresponding to a rectangular substrate. A first antenna portion(13a) is formed by winding a plurality of antenna wires in a spiral shape. The plurality of antenna wires of the first antenna portion forms four edge portions for the rectangular shaped plane. The plurality of antenna wires of the first antenna portion combines four edge portions at a position which is different from the rectangular shaped plane. A second antenna portion(13b) forms the central portion of the four sides of the rectangular shaped plane. The plurality of antenna wires of the second antenna portion is prepared in order to combine the central portion of four sides at the position which is different from the rectangular shaped plane.

Description

ANTENNA UNIT FOR INDUCTIVELY COUPLED PLASMA AND APPARATUS FOR INDUCTIVELY COUPLED PLASMA PROCESSING

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna unit for inductively coupled plasma used when performing inductively coupled plasma processing on a rectangular substrate such as a glass substrate for flat panel display (FPD) manufacturing, and an inductively coupled plasma processing apparatus using the same.

In a flat panel display (FPD) manufacturing process, such as a liquid crystal display (LCD), there exists a process of performing plasma processing, such as plasma etching and film-forming processing, on a rectangular rectangular substrate made of glass, and a plasma etching apparatus is performed in order to perform such plasma processing. Various plasma processing apparatuses, such as a plasma CVD film-forming apparatus, are used. Conventionally, a capacitively coupled plasma processing apparatus has been widely used as a plasma processing apparatus. In recent years, attention has been paid to an inductively coupled plasma (ICP) processing apparatus which has a great advantage that a high density plasma can be obtained with high vacuum.

The inductively coupled plasma processing apparatus arranges a high frequency antenna on an upper side of a dielectric window constituting a ceiling wall of a processing container containing a substrate to be processed, supplies a processing gas into the processing container, and supplies high frequency power to the high frequency antenna. By supplying, an inductively coupled plasma is generated in a processing container, and a predetermined plasma treatment is performed to the to-be-processed substrate by this inductively coupled plasma. As a high frequency antenna, the planar coil antenna which comprises a predetermined | prescribed planar shape is used abundantly.

In an inductively coupled plasma processing apparatus using a planar coil antenna, plasma is generated in a space immediately below the planar antenna in the processing vessel, but at that time, a high plasma density region and a low plasma are proportional to the electric field strength at each position immediately below the antenna. Because of the distribution of the density region, the pattern shape of the planar antenna has become an important factor in determining the plasma density distribution.

In the case of performing a plasma treatment on a rectangular substrate for manufacturing an FPD, a flat antenna is used that has a shape corresponding to the rectangular substrate as a whole. For example, Patent Document 1 has an outer antenna portion in which an arrangement region constituting the outer portion forms a frame shape, and an inner antenna portion in which the arrangement region similarly constitutes an inner portion provided in the outer antenna portion and forms an inner portion, and as a whole Disclosed is a planar antenna having a rectangular shape.

In the planar antenna disclosed in Patent Literature 1, the outer antenna portion and the inner antenna portion are arranged in a vortex such that the four antenna lines are shifted by 90 ° in position so that the whole becomes a substantially frame shape. In general, plasma has a property of being symmetrical because it is intended to diffuse isotropically, and even when such a frame-shaped antenna is used, the plasma of the edge portion tends to be weak, so that the edge portion is closer to the edge portion than the center portion of the edge. The number of turns is increased (see FIG. 2 of Cited Document 1).

(Prior art technical literature)

(Patent Literature)

(Patent Document 1) Japanese Unexamined Patent Publication No. 2007-311182

However, in recent years, it is required to control the plasma distribution of the edge part and the edge center in the outer area | region of a rectangular substrate more finely, and the technique of patent document 1 may be difficult to respond. For example, although there exists a request to raise the etching rate of a corner part, suppressing the etching rate of a side center part in the outer area | region of a rectangular board | substrate, the technique of patent document 1 is difficult to respond to such a request.

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

In order to solve the above problems, in a first aspect of the present invention, there is provided an antenna unit for inductively coupled plasma having a coil-shaped antenna for generating an inductively coupled plasma for plasma processing a rectangular substrate in a processing chamber of an inductively coupled plasma processing apparatus. The said antenna has the 1st antenna part and 2nd antenna part which the part which forms an induction electric field generally comprises the rectangular shape plane corresponding to the said rectangular substrate, and winds a plurality of antenna lines in a vortex shape. The plurality of antenna lines of the first antenna unit form four corner portions of the rectangular plane, and are provided to join the four corner portions at positions different from the rectangular plane, and the second antenna The negative plurality of antenna lines is 4 in the rectangular plane The center portion of the four sides is formed, and the center portion of the four sides is provided at a position different from the rectangular plane, and the first antenna portion and the second antenna portion are each independently supplied with high frequency power. An antenna unit for inductively coupled plasma is provided.

In the first aspect, the plurality of antenna lines constituting the first antenna portion are located above the first planar portion which becomes a portion between the first plane portion forming the corner portion and the first plane portion. The plurality of antenna lines that have a first three-dimensional portion in a retracted state, and the plurality of antenna lines constituting the second antenna portion include the second planar portion that forms the center portion of the side and the second planar portion that is part of the second planar portion. It can be set as the structure which has the 2nd solid part of the state which retracted to the upper surface of the planar part. The first antenna section and the second antenna section can be configured such that the four antenna lines are wound by shifting positions by 90 degrees in each.

In the second aspect of the present invention, a plurality of coil-shaped antennas for generating an inductively coupled plasma for plasma processing a rectangular substrate in a processing chamber of an inductively coupled plasma processing apparatus, and the plurality of antennas are portions for forming an induction electric field. An inductively coupled plasma antenna unit constituting the overall rectangular plane, and these antennas are arranged concentrically, at least the outermost periphery of the plurality of antennas, the rectangular plane corresponds to the rectangular substrate, And a first antenna portion and a second antenna portion formed by winding a plurality of antenna lines in a vortex shape, wherein the plurality of antenna lines of the first antenna portion form four corner portions of the rectangular plane, The four wools in positions different from the shape plane And a plurality of antenna lines of the second antenna portion, forming a central portion of four sides of the rectangular plane, and at a position different from the rectangular plane, at the center of the four sides. It is provided so as to combine, and the first antenna unit and the second antenna unit, each provides an antenna unit for inductively coupled plasma, characterized in that the high frequency power is independently supplied.

In the third aspect of the present invention, there is provided a processing chamber for accommodating a rectangular substrate and performing plasma processing, a mounting table on which a rectangular substrate is mounted in the processing chamber, a processing gas supply system for supplying a processing gas into the processing chamber, and the processing chamber. An inductively coupled plasma antenna unit having an exhaust system for evacuating the inside, a coil-shaped antenna for generating an inductively coupled plasma for plasma processing a rectangular substrate in the processing chamber, and a power supply mechanism for supplying high frequency power to the antenna; The antenna has a first antenna portion and a second antenna portion, each of which forms an induction electric field, which constitutes a rectangular planar plane corresponding to the rectangular substrate as a whole, and a plurality of antenna lines are wound in a spiral shape. A plurality of antenna lines of the first antenna unit is the rectangular In addition to forming four corner portions of the shape plane, the four corner parts are provided so as to join the four corner parts at a position different from the rectangular shape plane, and the plurality of antenna lines of the second antenna portion are the rectangular shape plane. The center portion of the four sides of the side is formed, and at a position different from the rectangular plane, the center portion of the four sides is provided to be coupled, and the power feeding mechanism is provided in the first antenna portion and the second antenna portion. Independently coupled to each other to provide an inductively coupled plasma processing apparatus for supplying a high frequency power.

In the fourth aspect of the present invention, there is provided a processing chamber for accommodating a rectangular substrate and performing plasma processing, a mounting table on which a rectangular substrate is mounted in the processing chamber, a processing gas supply system for supplying a processing gas into the processing chamber, and the processing chamber. An antenna unit for inductively coupled plasma having an exhaust system for exhausting the inside, a plurality of coil-shaped antennas for generating an inductively coupled plasma for plasma processing a rectangular substrate in the processing chamber, and a power supply mechanism for supplying high frequency power to the antenna; In the plurality of antennas, the portions forming the induction electric field generally constitute a rectangular plane, these antennas are arranged concentrically, and at least the outermost periphery of the plurality of antennas has a rectangular plane. A plurality of antennas corresponding to the rectangular substrate It has a 1st antenna part and a 2nd antenna part which wind a line in a vortex shape, The some antenna line of the said 1st antenna part forms four corner | angular parts of the said rectangular plane, and it is different from the said rectangular plane In another position, a plurality of antenna lines of the second antenna portion are provided so as to join the four corner portions, and at the same time form a central portion of four sides of the rectangular plane, and are different from the rectangular plane. The inductively coupled plasma processing apparatus of claim 4, wherein the center portion of the four sides is coupled to each other, and the power supply mechanism independently supplies high frequency power to the first antenna portion and the second antenna portion. to provide.

According to the present invention, the antenna comprises a rectangular plane in which a portion forming an induction electric field generally corresponds to a rectangular substrate, and the plurality of antenna lines of the first antenna unit forms four corner portions of the rectangular plane. In addition, in the position different from a rectangular plane, four edge parts are provided so that a couple of antenna lines may form the center part of four sides of a rectangular plane, In the other positions, the center portion of the four sides is provided to be coupled, and since the high frequency power is independently supplied to the first antenna portion and the second antenna portion, the electric field strength of the corner portion and the center portion of the side can be controlled. The plasma distribution control in the outer region of the rectangular substrate can be performed.

1 is a cross-sectional view showing an inductively coupled plasma processing apparatus according to an embodiment of the present invention.
FIG. 2 is a plan view illustrating an example of an antenna unit used in the inductively coupled plasma processing apparatus of FIG. 1.
3 is a plan view illustrating a first antenna part of a high frequency antenna used in the antenna unit of FIG. 2.
4 is a perspective view illustrating a first antenna unit of a high frequency antenna used in the antenna unit of FIG. 2.
FIG. 5 is a plan view illustrating a second antenna unit of the high frequency antenna used in the antenna unit of FIG. 2.
FIG. 6 is a perspective view illustrating a second antenna unit of the high frequency antenna used for the antenna unit of FIG. 2.
FIG. 7 is a diagram showing another embodiment for realizing individual current control of the first antenna unit and the second antenna unit. FIG.
8 is a view showing another form for realizing individual current control of the first antenna portion and the second antenna portion.
9 is a plan view illustrating an example of an antenna unit including an outer antenna and an inner antenna.
10 is a plan view showing another example of an antenna unit including an outer antenna and an inner antenna.
11 is a plan view showing an example of an antenna unit including an intermediate antenna in addition to the outer antenna and the inner antenna.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to an accompanying drawing. 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 a metal film, an ITO film, an oxide film, etc., or an ashing process of a resist film when forming a thin film transistor on a rectangular substrate such as a glass substrate for FPD. As FPD, a liquid crystal display, an electro luminescence (EL) display, a plasma display panel (PDP), etc. are illustrated.

This plasma processing apparatus has a prismatic airtight body container 1 made of a conductive material, for example, aluminum whose inner wall surface is anodized. This main body container 1 is assembled so that it can be decomposed | disassembled, and is grounded by the ground wire 1a. The main body container 1 is divided into the antenna chamber 3 and the processing chamber 4 up and down by the dielectric wall 2. Thus, the dielectric wall 2 constitutes a ceiling wall of the processing chamber 4. The dielectric wall 2 is made of ceramics such as Al ₂ O ₃ , quartz and the like.

In the lower portion of the dielectric wall 2, a shower housing 11 for supplying a processing gas is fitted. The shower housing 11 is provided in a cross shape and has a structure which supports the dielectric wall 2 from below. In addition, the shower housing 11 supporting the dielectric wall 2 is suspended from the ceiling of the main body container 1 by a plurality of suspenders (not shown).

The shower housing 11 is made of an anodized aluminum inner surface so that no contaminants are generated by corrosion with a conductive material, preferably a metal, for example, a processing gas. A gas flow passage 12 extending horizontally is formed in the shower housing 11, and a plurality of gas discharge holes 12a extending downward are in communication with the gas flow passage 12. On the other hand, the gas supply pipe 20a is provided in the center of the upper surface of the dielectric wall 2 so that it may communicate with this gas flow path 12. The gas supply pipe 20a penetrates from the ceiling of the main body container 1 to the outside thereof and is connected to a processing 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 processing chamber 4 is provided from the gas discharge hole 12a on the lower surface thereof. Is discharged within.

The support shelf 5 which protrudes inward is provided between the side wall 3a of the antenna chamber 3 in the main body container 1, and the side wall 4a of the process chamber 4, and this support shelf 5 The dielectric wall 2 is mounted on the top.

In the antenna chamber 3, an antenna unit 50 including a high frequency (RF) antenna 13 is disposed. When high frequency power is supplied to the high frequency antenna 13, an induction electric field is formed in the processing chamber 4, and the processing gas supplied from the shower housing 11 is converted into plasma by this induction electric field. In addition, the detail of the antenna unit 50 is mentioned later.

In the lower part of the process chamber 4, the mounting table 23 for mounting the rectangular substrate G is provided so as to face the high frequency antenna 13 with the dielectric wall 2 interposed therebetween. The mounting table 23 is made of a conductive material such as aluminum whose surface is anodized. The rectangular substrate G mounted on the mounting table 23 is attracted and held by an electrostatic chuck (not shown).

The mounting table 23 is housed in the insulator case 24 and is supported by the hollow support 25. The strut 25 penetrates the bottom of the main body container 1 while maintaining an airtight state, and is supported by a lifting mechanism (not shown) disposed outside the main body container 1, and is supported by the lifting mechanism at the time of carrying in and out of the rectangular substrate G. As a result, the mounting table 23 is driven in the vertical direction. Moreover, between the insulator case 24 which accommodates the mounting base 23, and the bottom of the main body container 1, the bellows 26 which surrounds the support | pillar 25 airtightly is arrange | positioned, and thereby mounts The airtightness in the processing container 4 is ensured also by the up-down movement of the base 23. Moreover, the sidewall 4a of the process chamber 4 is provided with the carry-in / out port 27a for carrying in and out of the rectangular substrate G, and the gate valve 27 which opens and closes it.

The high frequency power supply 29 is connected to the mounting table 23 via the matching device 28 by the feed line 25a provided in the hollow support 25. The high frequency power supply 29 applies a high frequency power for bias, for example, a high frequency power of 6 MHz to the mounting table 23 during the plasma processing. By this high frequency power for bias, ions in the plasma generated in the processing chamber 4 are attracted to the rectangular substrate G effectively.

Moreover, in the mounting table 23, in order to control the temperature of the rectangular substrate G, the temperature control mechanism which consists of heating means, such as a ceramic heater, a refrigerant | coolant flow path, etc., and a temperature sensor are provided (all are not shown). Piping and wiring to these mechanisms and members are all led out of the main body container 1 through the hollow support 25.

An exhaust device 30 including a vacuum pump or the like is connected to the bottom of the processing chamber 4 via an exhaust pipe 31. The exhaust chamber 30 exhausts the processing chamber 4, and during the plasma processing, the processing chamber 4 is set and held in a predetermined vacuum atmosphere (for example, 1.33 kPa).

A cooling space (not shown) is formed on the back side of the rectangular substrate G mounted on the mounting table 23, and a He gas flow passage 41 for supplying He gas as a gas for heat transfer at a constant pressure is provided. By supplying the heat transfer gas to the rear surface side of the rectangular substrate G in this manner, it is possible to avoid the temperature rise and the temperature change of the rectangular substrate G under vacuum.

Each component of this plasma processing apparatus is connected to the control part 80 which consists of a microprocessor (computer), and is controlled by it. In addition, the control unit 80 includes a user interface 81 including a keyboard for performing an input operation such as a command input for managing a plasma processing apparatus by an operator, a display for visualizing and displaying the operation status of the plasma processing apparatus, and the like. Connected. In addition, the control unit 80 includes a control program for realizing various processes executed in the plasma processing apparatus under the control of the control unit 80, or a program for executing the processing in each component of the plasma processing apparatus in accordance with processing conditions, that is, The storage unit 82 in which the processing recipe is stored is connected. The processing recipe is stored in the storage medium in the storage unit 82. The storage medium may be a hard disk or a semiconductor memory built into a computer, or may be a portable medium such as a CDROM, a DVD, a flash memory, or the like. Further, the recipe may be appropriately transmitted from another device, for example, via a dedicated line. Then, if necessary, the plasma processing apparatus is controlled under the control of the control unit 80 by calling an arbitrary processing recipe from the storage unit 82 and executing the control unit 80 by an instruction from the user interface 81 or the like. The desired processing in is performed.

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

FIG. 2 is a plan view showing an example of an antenna unit used in the antenna unit of the apparatus of FIG. 1, FIG. 3 is a plan view showing a first antenna portion of a high frequency antenna used in the antenna unit of FIG. 2, and FIG. 4 is an antenna unit of FIG. 5 is a plan view showing a first antenna portion of the high frequency antenna used in FIG. 5, FIG. 5 is a plan view showing a second antenna portion of the high frequency antenna used in the antenna unit of FIG. 2, and FIG. 6 is a second view of the high frequency antenna used in the antenna unit of FIG. It is a perspective view which shows an antenna part.

As shown in FIG. 2, the high frequency antenna 13 of the antenna unit 50 has a rectangular shape (frame) in which a portion facing the dielectric wall 2 forming an induction electric field contributing to plasma generation corresponds to a rectangular substrate G as a whole. Shape) and the 1st antenna part 13a and the 2nd antenna part 13b which wind a some antenna line in a vortex shape. The antenna line of the 1st antenna part 13a forms four corner | angular parts of a rectangular planar surface, and is provided so that the four corner | parts may be joined in a position different from a rectangular planar plane. The antenna line of the second antenna portion 13b forms a central portion of four sides of the rectangular plane, and is provided to engage the central portions of these four sides at a position different from the rectangular plane.

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

As shown in FIG. 1, the 1st power supply member 16a is respectively connected to the four terminal 22a of the 1st antenna part 13a, and it is respectively connected to the four terminals 22b of the 2nd antenna part 13b. The second power feeding member 16b is connected (only one is shown in FIG. 1). Four first feed members 16a are connected to a feed line 19a, and four second feed members 16b are connected to a feed line 19b. The matching line 14a and the 1st high frequency power supply 15a are connected to the feed line 19a, and the matching line 14b and the 2nd high frequency power supply 15b are connected to the feed line 19b. Thereby, the high frequency power of which the frequency is 13.56 MHz is independent from the 1st high frequency power supply 15a and the 2nd high frequency power supply 15b to the 1st antenna part 13a and the 2nd antenna part 13b, respectively. It is supplied, and the control part 80 is able to control the current value supplied to these independently.

The high frequency antenna 13 is disposed apart from the dielectric wall 2 by a spacer 17 made of an insulating member, and the arrangement region corresponds to the rectangular substrate G.

As shown in FIGS. 3 and 4, the first antenna portion 13a forming the four corner portions of the rectangular plane of the high frequency antenna 13 has four antenna lines 61, 62, 63, and 64. The multi (quadruple) antenna is constructed so that the planar shape becomes a picture frame shape by winding. Specifically, the antenna lines 61, 62, 63, and 64 are wound by shifting positions by 90 degrees, and the portion forming the four corner portions of the rectangular plane facing the dielectric wall 2 is formed by a plane portion ( 61a, 62a, 63a, 64a, and the portion between these planar portions 61a, 62a, 63a, 64a is retracted upward so as to be in a position different from the rectangular plane. 62b, 63b, 64b). These solid portions 61b, 62b, 63b, 64b are disposed at positions not contributing to the generation of plasma.

Moreover, as shown to FIG. 5 and FIG. 6, the 2nd antenna part 13b which comprises the center part of the four sides of the said rectangular plane of the high frequency antenna 13 has four antenna lines 71, 72, 73, and; 74 is wound so that a multiple (quadruple) antenna is formed so that the plane shape becomes a frame shape. Specifically, the antenna lines 71, 72, 73, and 74 are wound by shifting positions by 90 degrees, and the portion forming the central portion of the four sides of the rectangular plane facing the dielectric wall 2 is formed by a flat portion ( 71a, 72a, 73a, 74a, and the portion between these planar portions 71a, 72a, 73a, 74a is retracted upward so as to be in a position different from the rectangular plane. 72b, 73b, 74b). These solid portions 71b, 72b, 73b, 74b are disposed at positions not contributing to the generation of plasma.

The antenna lines 61, 62, 63, and 64 of the first antenna portion 13a are fed through the four terminals 22a and the feed lines 69 described above, and the antenna lines of the second antenna portion 13b ( 71 72, 73, and 74 are fed through the four terminals 22b and the feed line 79 described above.

Next, the processing operation at the time of performing a plasma etching process with respect to the rectangular substrate G using the inductively coupled plasma processing apparatus comprised as mentioned above is demonstrated.

First, the rectangular substrate G is carried in into the process chamber 4 by the conveyance mechanism (not shown) from the gate valve 27 opened, and it mounts on the mounting surface of the mounting table 23, and then the electrostatic chuck (illustration) Rectangular substrate G is fixed on the mounting table 23 by means of (not shown). Next, while discharging the processing gas supplied from the processing gas supply system 20 into the processing chamber 4 from the gas discharge hole 12a of the shower housing 11 into the processing chamber 4, the exhaust apparatus 30 is discharged to the exhaust apparatus 30. By evacuating the inside of the processing chamber 4 through the exhaust pipe 31, the inside of the processing chamber is maintained in a pressure atmosphere of, for example, about 0.66 to 26.6 kPa.

At this time, the He gas is supplied as the heat transfer gas through the He gas flow passage 41 in order to avoid the temperature rise and the temperature change of the rectangular substrate G in the cooling space on the rear surface side of the rectangular substrate G.

Next, a high frequency of 13.56 MHz, for example, is formed from the first high frequency power source 15a and the second high frequency power source 15b, and the first antenna part 13a and the side center part which respectively constitute corner portions of the high frequency antenna 13 are constituted. Is applied to the second antenna portion 13b, thereby forming an induction electric field corresponding to the rectangular substrate G in the processing chamber 4 through the dielectric wall 2. The induction electric field thus formed causes plasma processing gas in the processing chamber 4 to generate a uniform high density inductively coupled plasma in a region corresponding to the rectangular substrate G.

As a result, the high frequency antenna 13 has a frame shape in which the overall shape formed by the first antenna portion 13a and the second antenna portion 13b of the portion facing the dielectric wall 2 corresponds to the rectangular substrate G. Therefore, the plasma can be supplied to the entire rectangular substrate G.

As described above, since the plasma of the edge portion tends to be weakened only by forming the antenna line in a frame shape as in the related art, in Patent Document 1, the number of turns of the antenna line increases in the corner portion than in the center portion of the side. Although the uniformity of plasma is aimed at, in recent years, the plasma distribution of the edge part and edge center in the outer area | region of a rectangular substrate is controlled more finely, and the technique of patent document 1 is difficult to respond.

Therefore, in the present embodiment, the high frequency antenna 13 constitutes a rectangular (frame) plane in which the part facing the dielectric wall 2 forming the induction electric field contributing to the plasma generation corresponds to the rectangular substrate G as a whole. And a first antenna portion 13a in which the antenna lines form four corner portions, and a second antenna portion 13b in which the antenna lines form a central portion of four sides, and the first antenna portion 13a and Independently supply the high frequency power from the first high frequency power supply 15a and the second high frequency power supply 15b to the second antenna unit 13b, and control the current values flowing through them by the control unit 80. As a result, the plasma distribution at the corner portion and the edge center in the outer region of the rectangular substrate G can be more finely controlled, and the desired plasma treatment can be performed.

In addition, the first antenna portion 13a constitutes a multiple (quadruple) antenna in which the four antenna lines 61, 62, 63, and 64 are shifted in positions of 90 degrees so that the flat shape wound around them becomes a frame shape. At the positions corresponding to the four corner portions, between the planar portions 61a, 62a, 63a, 64a and the planar portions 61a, 62a, 63a, 64a contributing to the generation of plasma facing the dielectric wall 2; The portion is formed of three-dimensional portions 61b, 62b, 63b, and 64b upwardly retracted so as not to contribute to plasma generation, and the second antenna portion 13b also has four antenna lines 71, 72, 73, and 74. A quadruple antenna in which the planar shape wound by shifting the position by 90 ° is formed into a frame shape, and at a position corresponding to the centers of the four sides, the plane contributing to the generation of plasma facing the dielectric wall 2. The portions 71a, 72a, 73a, 74a, and the portions between these flat portions 71a, 72a, 73a, 74a do not contribute to plasma generation. And the three-dimensional portions 71b, 72b, 73b, 74b, which have been evacuated from each other, and the first antenna portion 13a and the second antenna portion 13b basically follow a conventional form of multiple antennas, and relatively combine them. By the simple configuration, independent plasma distribution control can be realized in the corner portion and the edge center portion.

In the above, the frame-shaped high frequency antenna 13 is constituted by the two antenna parts of the first antenna part 13a corresponding to the corner portion and the second antenna part corresponding to the center of the edge, and these are independently controlled by current. Although the example which made it possible was shown, you may comprise three or more antenna parts, and you may make them control current independently. For example, the center of the side may be divided into two antenna parts of the second antenna part and the third antenna part, and the center of the side may be divided into three, and the middle part divided into three may be divided into the second antenna part and the middle part between the middle part. The configuration may be the same as that of the third antenna unit. In addition, the configuration similar to this is possible.

In addition, instead of connecting separate high frequency power supplies to the first antenna section 13a and the second antenna section 13b to perform current value control, as shown in FIG. 7, high frequency power from one high frequency power supply 15 is used. After dividing into the power splitter 83, the high frequency power is supplied to each of the first antenna portion 13a and the second antenna portion 13b via the matchers 14a and 14b, and the first antenna portion 13a and the first antenna portion 13a. The current value control of the second antenna unit 13b may be performed. Thereby, a load of equipment can be reduced by one high frequency power supply. 8, the current value of the 1st antenna part 13a and the 2nd antenna part 13b by providing the impedance adjustment mechanism 84 which consists of a variable capacitor etc. in either of the feed line 19a or 19b. Control may be performed. In this case, what is necessary is just to provide one high frequency power supply 15 and one matcher 14, and can reduce a burden on equipment.

Next, another example of the antenna unit will be described.

9 is a plan view illustrating another example of the antenna unit. When the rectangular substrate G becomes large, the plasma power of the center portion is weakened only by the frame-shaped high frequency antenna 13 whose contour is rectangular, making it difficult to form a uniform plasma. So, in this example, as shown in FIG. 9, the said high frequency antenna 13 is arrange | positioned as an outer antenna, and the inner side antenna 113 of the frame shape which has a concentric rectangular outline is arrange | positioned inside it, The antenna unit 50a is constituted, and the plasma density of the inner region corresponding to the center 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 high frequency antenna 13. That is, the planar shape of the part facing the dielectric wall 2 forms a frame shape as a whole, among which the first antenna part 113a constituting four corner parts and the second antenna part 113b constituting the center part of each side. Has Like the high 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 controlled independently. Thereby, the plasma density distribution of the edge part and edge center part of the inner antenna 113 can also be adjusted, and it can make plasma density more uniform.

However, since the nonuniformity of the plasma density in the center and corners of the edge is most prominent in the outer circumference, only the outer antenna is constituted by the high frequency antenna 13 so that the plasma density distribution can be sufficiently controlled. The antenna may not necessarily be the same as the high frequency antenna 13, and is not particularly limited as long as at least the outer antenna can independently control the current values of the corner portion and the side center portion. For example, the antenna unit 50b having the inner antenna 123 as shown in FIG. 10 may be used. That is, the inner antenna 123 constitutes a multiple (quadruple) antenna in which four antenna lines 91, 92, 93, and 94 are wound to form an entire spiral shape. Specifically, the antenna lines 91, 92, 93, and 94 are wound by shifting positions by 90 degrees, and the arrangement area of the antenna lines forms a substantially frame shape, and the number of turns of the edge portion where the plasma tends to be weakened is changed. I am going to increase more than the number of turns of the center. In the example of illustration, the number of turns of a corner part is three, and the number of turns of the center part of a side is two. Further, the crank portion (bending portion) 98 is formed on each antenna line such that the plasma generation region enclosed by the outer and inner lines of the inner antenna 123 is line symmetrical (mirror symmetry) with respect to the centerline crossing two opposite sides. Since the plasma generation region is formed, the plasma generation region can be aligned to the rectangular substrate G. That is, the plasma of the state uniform to the rectangular substrate G can be produced, and the uniformity of plasma can be improved.

As the inner antenna, a conventional multiple antenna such as Patent Document 1 may be used.

Moreover, you may arrange | position three or more frame-shaped antennas concentrically. In this case, it is necessary for at least the outermost antenna to be able to perform current control independently of at least the two portions of the corner portion and the side center.

11, the antenna unit 50c provided with the intermediate antenna 133 of the same structure as the said 1st antenna part 13a between the outer antenna 13 and the inner antenna 123 may be sufficient. . With this configuration, it is possible to perform partial plasma distribution control, that is, to reinforce only the corner portion of the region between the outer antenna 13 and the inner antenna 123, thereby improving controllability of the plasma distribution. Instead of the intermediate antenna 133, an intermediate antenna having the same configuration as that of the second antenna unit 13b may be provided between the outer antenna 13 and the inner antenna 123 to perform partial plasma distribution control. Instead of the intermediate antenna 133, an antenna such as an outer antenna 13 composed of an antenna portion such as the antenna portion 13a and an antenna portion such as the antenna portion 13b may be provided. That is, in the triple antenna which consists of an outer antenna, an intermediate antenna, and an inner antenna, an outer antenna and an intermediate antenna become the structure of the split antenna disclosed in this application. This configuration can realize a plasma processing apparatus capable of uniform processing even when the substrate to be processed is further enlarged. It goes without saying that the inner antenna is not limited to the configuration of the inner antenna 123.

In addition, this invention can be variously modified without being limited to the said embodiment. For example, the layout of the antenna lines in the antenna is not limited to that shown in the above embodiments, and has at least a rectangular outline covering the outer periphery of the rectangular substrate, and a portion corresponding to the outer periphery of the rectangular substrate has at least two regions. However, the present invention is not limited as long as the current values in these areas can be controlled independently. In addition, although the example of the number of turns of an antenna line was shown, it is not limited to this. In addition, although the antenna was configured as a quadruple antenna in which four antenna lines were wound to form a spiral, the antenna may be configured as multiple antennas other than quadruple.

In the above embodiment, the structure in which the ceiling of the processing chamber is constituted by the dielectric wall and the antenna is disposed on the upper surface of the dielectric wall of the ceiling outside the processing chamber has been described. If possible, the antenna may be arranged in the processing chamber.

In addition, in the said embodiment, although the case where this invention was applied to the etching apparatus was shown, it can apply to other plasma processing apparatuses, such as CVD film-forming. Moreover, although the example which used the FPD board | substrate was shown as a rectangular board | substrate, it is applicable also when processing other rectangular board | substrates, such as a solar cell.

1: body container
2: dielectric wall (dielectric member)
3: antenna chamber
4: treatment chamber
13: high frequency antenna
13a: first antenna unit
13b: second antenna unit
14: Matching machine
15: high frequency power supply
15a: first high frequency power supply
15b: second high frequency power supply
16a, 16b: feeding member
19, 19a, 19b: feeder
20: process gas supply system
22a, 22b: terminal
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 wire
61a, 62a, 63a, 64a, 71a, 72a, 73a, 74a: flat part
61b, 62b, 63b, 64b, 71b, 72b, 73b, 74b: solid part
69, 79: feeder
80: control unit
81: user interface
82: memory
83: power splitter
84: impedance adjustment mechanism
98: bend
113, 123: inner antenna
113a: first antenna unit
113b: second antenna unit
133: intermediate antenna
G: rectangular substrate

Claims (8)

An antenna unit for inductively coupled plasma having a coil-shaped antenna for generating an inductively coupled plasma for plasma processing a rectangular substrate in a processing chamber of an inductively coupled plasma processing apparatus,
The said antenna has a 1st antenna part and a 2nd antenna part which the part which forms an induction electric field generally comprises the rectangular shape plane corresponding to the said rectangular substrate, and winds a plurality of antenna lines in a vortex shape,
The plurality of antenna lines of the first antenna unit are provided so as to form four corner portions of the rectangular plane and to couple the four corner portions at a position different from the rectangular plane.
The plurality of antenna lines of the second antenna unit are provided so as to form a central portion of four sides of the rectangular plane, and to combine the central portions of the four sides at a position different from the rectangular plane.
The first antenna unit and the second antenna unit are each independently supplied with high frequency power
An antenna unit for inductively coupled plasma, characterized in that.
The method of claim 1,
The plurality of antenna lines constituting the first antenna portion include a first three-dimensional portion in a state where the first planar portion forming the corner portion and the first planar portion which becomes a portion between the first planar portion and the retracted upwards Have wealth,
The plurality of antenna lines constituting the second antenna portion include a second three-dimensional portion in a state where the second planar portion that forms the center portion of the side and the second planar portion that becomes a portion between the second planar portion and retract upwards Wealthy
An antenna unit for inductively coupled plasma, characterized in that.
3. The method according to claim 1 or 2,
The antenna unit for inductively coupled plasma, wherein the first antenna unit and the second antenna unit are wound by shifting four antenna lines by 90 ° in each.
And a plurality of coil-shaped antennas for generating an inductively coupled plasma for plasma processing the rectangular substrate in the processing chamber of the inductively coupled plasma processing apparatus, wherein the plurality of antennas form a rectangular plane as a whole of a portion forming the induction field. An antenna unit for inductively coupled plasma in which these antennas are arranged concentrically,
At least the outermost periphery of the plurality of antennas has a first antenna portion and a second antenna portion whose rectangular plane corresponds to the rectangular substrate, and which comprises a plurality of antenna lines wound in a spiral shape,
The plurality of antenna lines of the first antenna unit are provided so as to form four corner portions of the rectangular plane and to couple the four corner portions at a position different from the rectangular plane.
The plurality of antenna lines of the second antenna unit are provided so as to form a central portion of four sides of the rectangular plane, and to combine the central portions of the four sides at a position different from the rectangular plane.
The first antenna unit and the second antenna unit are each independently supplied with high frequency power
An antenna unit for inductively coupled plasma, characterized in that.
The method of claim 4, wherein
Of the plurality of antennas, any one other than the outermost circumference has a plurality of antenna lines, and a part of the plurality of antennas forms a portion which forms an induction field disposed at a desired portion, and the remaining portion forms an induction field. An antenna unit for inductively coupled plasma, characterized in that it has a configuration that is a retracted portion that does not.
A processing chamber which accommodates a rectangular substrate and performs plasma processing;
A mounting table on which a rectangular substrate is mounted in the processing chamber;
A process gas supply system for supplying a process gas into the process chamber,
An exhaust system for exhausting the inside of the processing chamber;
An antenna unit for inductively coupled plasma having a coil-shaped antenna for generating an inductively coupled plasma for plasma processing a rectangular substrate in the processing chamber;
Power feeding mechanism for feeding high frequency power to the antenna
And,
The said antenna has a 1st antenna part and a 2nd antenna part which the part which forms an induction electric field generally comprises the rectangular shape plane corresponding to the said rectangular substrate, and winds a plurality of antenna lines in a vortex shape,
The plurality of antenna lines of the first antenna unit are provided so as to form four corner portions of the rectangular plane and to couple the four corner portions at a position different from the rectangular plane.
The plurality of antenna lines of the second antenna unit are provided so as to form a central portion of four sides of the rectangular plane, and to combine the central portions of the four sides at a position different from the rectangular plane.
The power supply mechanism independently supplies high frequency power to the first antenna portion and the second antenna portion, respectively.
Inductively coupled plasma processing apparatus, characterized in that.
A processing chamber which accommodates a rectangular substrate and performs plasma processing;
A mounting table on which a rectangular substrate is mounted in the processing chamber;
A process gas supply system for supplying a process gas into the process chamber,
An exhaust system for exhausting the inside of the processing chamber;
An antenna unit for inductively coupled plasma having a plurality of coil-shaped antennas for generating inductively coupled plasma for plasma processing a rectangular substrate in the processing chamber;
Power feeding mechanism for feeding high frequency power to the antenna
And,
In the plurality of antennas, portions forming the induction electric field generally constitute a rectangular plane, these antennas are arranged concentrically, and at least the outermost periphery of the plurality of antennas has a rectangular plane that is the rectangular substrate. And a first antenna portion and a second antenna portion formed by winding a plurality of antenna lines in a vortex shape,
The plurality of antenna lines of the first antenna unit are provided so as to form four corner portions of the rectangular plane and to couple the four corner portions at a position different from the rectangular plane.
The plurality of antenna lines of the second antenna unit are provided so as to form a central portion of four sides of the rectangular plane, and to combine the central portions of the four sides at a position different from the rectangular plane.
The power supply mechanism independently supplies high frequency power to the first antenna portion and the second antenna portion, respectively.
Inductively coupled plasma processing apparatus, characterized in that.
The method according to claim 6 or 7,
And a control unit for controlling a current value flowing in the first antenna unit and a current value flowing in the second antenna unit.

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