KR20130054184A - High-frequency antenna circuit and inductively coupled plasma processing apparatus - Google Patents

Abstract

PURPOSE: A high-frequency antenna circuit and an inductively coupled plasma processing device are provided to improve power efficiency by suppressing heat generation of a matching circuit. CONSTITUTION: A high-frequency antenna circuit includes a plasma generation antenna(16), a high-frequency power supply(18), and a matching circuit(19). The plasma generation antenna is composed of multiple sectionalized antennas(16-1,...,16-5) and generates plasma in a processing chamber. The high-frequency power supply supplies high-frequency power to the plasma generation antenna. The matching circuit is inserted between the high-frequency power supply and the plasma generation antenna. The multiple sectionalized antennas form the plasma generation antenna, and high-frequency power is distributed to the multiple sectionalized antennas after passing through the matching circuit. Parallel resonance capacitor circuits(30-1,...,30-5) are installed at each of the multiple sectionalized antennas in parallel.

Description

HIGH FREQUENCY ANTENNA CIRCUIT AND INDUCTIVELY COUPLED PLASMA PROCESSING APPARATUS}

The present invention relates to a high frequency antenna circuit and an inductively coupled plasma processing apparatus.

With the increase in the size of the glass substrate used for FPD, the plasma apparatus which processes this is also required to control plasma of a large area. Conventionally, although an inductively coupled plasma processing apparatus capable of obtaining a high density plasma has been used for processing a glass substrate, in order to comply with the above requirements, a method that can be divided into antennas and controlled for each divided antenna has been taken.

As a method of a split antenna, one is comprised by the spiral antenna comprised by the some antenna piece, and the dielectric or aluminum arrange | positioned between the said spiral antenna and a process chamber, and by combination with the window divided into multiple numbers (patent document 1). Moreover, as another method, what arrange | positioned the linear antenna for every divided aluminum window (patent document 1 similarly) is used.

In addition, Patent Literature 2 describes a technique in which a parallel resonant circuit is provided in an antenna and the current flowing through the antenna is increased.

Japanese Patent Laid-Open No. 2011-029584 Japanese Patent Laid-Open No. 2010-135298

However, in an inductively coupled plasma processing apparatus having a split antenna and distributing and supplying current through a matching circuit from a high frequency power source, if a large induction field is to be formed inside the processing chamber, the current to be distributed to each split antenna must be increased. do. As a result, a large current flows through the matching circuit, the matching circuit generates heat, and the power loss increases.

In order to suppress the heat generation of the matching circuit, the distribution current distributed to each of the divided antennas from the high frequency power supply through the matching circuit may be reduced. However, when the distribution current is reduced, it is difficult to form a sufficient induction electric field inside the processing chamber.

The present invention provides a high frequency that can form a sufficient induction electric field inside a processing chamber of an inductively coupled plasma processing apparatus that includes a split antenna and distributes and supplies current from a high frequency power source through a matching circuit while suppressing heat generation of the matching circuit. An antenna circuit and an inductively coupled plasma processing apparatus are provided.

A high frequency antenna circuit according to a first aspect of the present invention is a high frequency antenna circuit for generating an inductively coupled plasma in a processing chamber for processing a substrate in an inductively coupled plasma processing apparatus, and a plasma generating antenna for generating plasma in the processing chamber. And a high frequency power supply for supplying high frequency power to the plasma generating antenna, a matching circuit interposed between the high frequency power supply and the plasma generating antenna, and a high frequency power after passing through the matching circuit. And a plurality of divided antennas to be distributed and a parallel resonant capacitor circuit provided in parallel to each of the plurality of divided antennas.

An inductively coupled plasma processing apparatus according to a second aspect of the present invention is an inductively coupled plasma processing apparatus for generating an inductively coupled plasma in a processing chamber for processing a substrate, and is provided on a ceiling plate provided above the processing chamber and on the ceiling plate. And a plasma generating antenna comprising a plurality of split antennas, and a parallel resonant capacitor circuit provided in parallel with each of the plurality of split antennas.

According to the present invention, it is possible to provide a high frequency antenna circuit and an inductively coupled plasma processing apparatus capable of improving the power efficiency of an inductively coupled plasma processing apparatus having a split antenna while suppressing heat generation of the matching circuit.

1 is a cross-sectional view schematically showing an inductively coupled plasma processing apparatus according to an embodiment of the present invention.
FIG. 2A is a plan view illustrating an example of a metal window and a high frequency antenna of the inductively coupled plasma processing apparatus shown in FIG. 1. FIG.
2B is a plan view illustrating an example of a metal window and a high frequency antenna in the case of nine divisions.
2C is a plan view illustrating an example of a metal window and a high frequency antenna in the case of 25 divisions.
3 is a circuit diagram showing an example of a circuit of a high frequency antenna circuit included in the inductively coupled plasma processing apparatus in one embodiment of the present invention.
4 is a circuit diagram showing a first modification of the high frequency antenna circuit.
5 is a circuit diagram showing a second modification of the high frequency antenna circuit.
6 is a plan view illustrating a first modification of the split antenna;
FIG. 7 is a circuit diagram showing a circuit example of a high frequency antenna circuit included in the inductively coupled plasma processing apparatus having the split antenna shown in FIG. 6. FIG.
8 is a circuit diagram illustrating a third modification of the high frequency antenna circuit.
9 is a circuit diagram showing a fourth modification of the high-frequency antenna circuit.
10 is a circuit diagram showing a fifth modification of the high-frequency antenna circuit.
11 is a circuit diagram showing a sixth modification example of the high-frequency antenna circuit.
12 is a plan view illustrating a second modification of the divided antenna;
FIG. 13 is a circuit diagram illustrating one circuit example of a high frequency antenna circuit included in an inductively coupled plasma processing apparatus having a split antenna shown in FIG. 12. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to an accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows schematically the inductively coupled plasma processing apparatus which concerns on one Embodiment of this invention, and FIG. 2A is a top view which shows an example of the metal window and the high frequency antenna of the inductively coupled plasma processing apparatus shown in FIG. This apparatus is used for the etching of a metal film, an ITO film, an oxide film, etc. at the time of forming a thin film transistor on the glass substrate for FPDs, and the ashing process of a resist film, for example. Here, as FPD, a liquid crystal display (LCD), an electroluminescence (EL) display, a plasma display panel (PDP), etc. are illustrated.

As shown in Fig. 1, the inductively coupled plasma processing apparatus has a rectangular cylindrical hermetic processing chamber 1 made of a conductive material, for example, aluminum whose inner wall surface is anodized (anodized). The processing chamber 1 is grounded by the ground wire 1a.

The inside of the processing chamber 1 is divided into the antenna chamber 3 and the processing chamber 4 up and down by the metal window 2 formed insulated from the processing chamber 1. In this example, the metal window 2 constitutes a ceiling plate provided inside the processing chamber 1, and is made of, for example, a nonmagnetic material and a conductive metal. Examples of the nonmagnetic and conductive metal are aluminum or an alloy containing aluminum.

Between the side wall 3a of the antenna chamber 3 and the side wall 4a of the processing chamber 4, the cross shape also serves as a support shelf 5 protruding into the processing chamber 1 and a shower housing for supplying the processing gas. Support beams 6 are provided. When the support beam 6 also serves as a shower housing, a processing gas flow path 7 is formed inside the support beam 6 to extend parallel to the surface to be processed of the substrate G to be processed. The process gas flow path 7 communicates with a plurality of process gas discharge holes 7a for discharging the process gas into the process chamber 4.

The process gas supply pipe 8 is connected to the upper part of the support beam 6 so that it may communicate with the gas flow path 7. The process gas supply pipe 8 penetrates from the ceiling of the process chamber 1 to the outside of the process chamber 1 and is connected to a process gas supply system 9 including a process gas supply source, a valve system, and the like. At the time of plasma processing, process gas is supplied from the process gas supply system 9 to the process gas flow path 7 of the support beam 6 via the process gas supply pipe 8, and the process gas discharge hole 7a. Is discharged from the inside of the processing chamber 4. The support shelf 5 and the support beam 6 are made of a conductive material, preferably metal. An example of the metal is aluminum.

In this example, the metal window 2 is divided into four parts as the metal windows 2-1 to 2-4 as shown in FIG. 2A. In this example, the planar shape of the processing chamber 4 is rectangular. In this example, the support beam 6 is formed in a cross shape when viewed from a plane so as to connect the midpoints of the sides from the center of the rectangle, and the support shelf 5 is formed around the support beam 6 of the cross shape. Surround. Thereby, four openings are formed in a lattice pattern between the support shelf 5 and the support beam 6. Each of the four metal windows 2-1 to 2-4 is mounted on the support shelf 5 and the support beam 6 via the insulator 10 so as to close the four openings, respectively. Thereby, the metal windows 2-1 to 2-4 are insulated from the support shelf 5, the support beam 6, and the processing chamber 1, and the metal windows 2-1 to 2-4. ) Are also insulated from each other. The material of the insulator 10 is, for example, ceramic or polytetrafluoroethylene (PTFE). In addition, the cross section cut along the line I-I shown in FIG. 2A corresponds to the cross section shown in FIG.

The mounting table 11 is disposed on the bottom wall 4b of the processing chamber 4. The mounting table 11 is made of a conductive material, for example, aluminum whose surface is anodized, and is disposed on the bottom wall 4b in a state insulated from the bottom wall 4b by the insulator 12. In addition, the mounting table 11 is connected to the bias power supply 23 via the matching circuit 22 in this example. On the loading surface of the loading table 11, the to-be-processed substrate G, for example, an LCD glass substrate, is mounted. The to-be-processed substrate G mounted on the mounting table 11 is adsorbed and held on the mounting surface of the mounting table 11 by an electrostatic chuck (not shown) provided inside the mounting table 11.

Moreover, the carry-in / out port 4c for carrying in and out of the to-be-processed substrate G is formed in the side wall 4a of the process chamber 4. The inlet / outlet 4c is opened and closed by the gate valve 13.

In addition, an exhaust port 4d is formed in the bottom wall 4b of the processing chamber 4. The exhaust pipe 14 is connected to the exhaust port 4d. The exhaust pipe 14 is connected to an exhaust device 15 including a vacuum pump and the like. The exhaust device 15 exhausts the inside of the processing chamber 4 through the exhaust pipe 14 and the exhaust port 4d. The inside of the processing chamber 4 is set to a predetermined vacuum degree, for example, a low pressure, for example, 1.33 Pa, while plasma processing is performed with respect to the to-be-processed substrate G, for example.

Inside the antenna chamber 3, a radio frequency (RF) antenna 16 is disposed so as to face each of the metal windows 2-1 to 2-4. The high frequency antenna 16 is spaced apart from the metal windows 2-1 to 2-4 by the spacer 21 made of an insulating member. The high frequency antenna 16 is a plasma generating antenna that generates plasma inside the processing chamber 1 and, in this example, inside the processing chamber 4.

The high frequency antenna 16 of this example is divided into four corresponding to the metal windows 2-1 to 2-4, and each of the divided antennas 16-1 to 16 is independent for each of the metal windows 2-1 to 2-4. It is comprised as a collection of -4). As shown in Fig. 2, the divided antennas 16-1 to 16-4 of this example each include a plurality of linear antennas, and in this example, four linear antennas. The plurality of linear antennas of the present example are arranged to traverse the metal windows 2-1 to 2-4 from one end to the other end of the metal windows 2-1 to 2-4, and are connected in parallel with each other. In addition, the circuit example of a high frequency antenna circuit is mentioned later.

To one end of each of the divided antennas 16-1 to 16-4, a power supply member (only 17-1 to 17-4 (17-1, 17-2) is shown in FIG. 1) is connected. The high frequency power is distributed and supplied to the divided antennas 16-1 to 16-4 through the matching circuit 19 and the power supply members 17-1 to 17-4 from the high frequency power source 18. An example of the frequency of high frequency power is 13.56 MHz, for example. The matching circuit 19 interposed between the high frequency power source 18 and the split antennas 16-1 to 16-4 is a circuit that performs impedance matching between the high frequency power source 18 side and the plasma load side, and generally a matcher. It is called. The matcher includes a variable capacitor or variable inductor, or a variable capacitor and a variable inductor therein, and performs impedance matching between the high frequency power supply 18 side and the plasma load side by controlling the capacitance of the capacitor and the inductance of the inductor. .

The other end of each of the split antennas 16-1 to 16-4 is connected to the side wall 3a of the antenna chamber 3 or a ground potential member separately provided, for example, and grounded. In that case, the terminal capacitor | condenser may be provided between the division antennas 16-1 to 16-4 and the ground potential member, such as the side wall 3a of the antenna chamber 3 and the like.

The high frequency electric power supplied to the split antennas 16-1 to 16-4 forms an induction electric field in the process chamber 4. The processing gas discharged from the gas discharge hole 7a into the processing chamber 4 is converted into plasma by an induction electric field formed in the processing chamber 4.

The inductively coupled plasma processing apparatus is configured to be connected to and controlled by a control unit 50 made of a computer. The user interface 51 and the storage unit 52 are connected to the control unit 50. The user interface 51 includes a keyboard for the process manager to perform command input operations and the like for managing the inductively coupled plasma processing apparatus, a display for visualizing and displaying the operation status of the inductively coupled plasma processing apparatus. In the storage unit 52, a control program for realizing various processes executed by the inductively coupled plasma processing apparatus by the control of the control unit 50, or the respective components of the inductively coupled plasma processing apparatus in accordance with processing conditions are executed. The program to be executed, i.e. the recipe, is stored. The recipe may be stored in a hard disk or a semiconductor memory, or may be set in a predetermined position of the storage unit 52 in a state of being accommodated in a portable storage medium such as a CD-ROM or a DVD. In addition, the recipe may be appropriately transmitted from another apparatus via, for example, a dedicated line. Then, if necessary, an arbitrary recipe is called from the storage unit 52 by the instruction from the user interface 51 and executed in the control unit 50, so that the inductively coupled plasma processing apparatus is controlled under the control of the control unit 50. The desired process of is performed.

3 is a circuit diagram showing an example of a circuit of a high frequency antenna circuit included in the inductively coupled plasma processing apparatus according to the embodiment of the present invention.

As shown in FIG. 3, the high frequency antenna circuit includes the high frequency antenna (plasma generating antenna) 16, the high frequency power source 18, and the matching circuit 19 described above. The high frequency antenna 16 is composed of a plurality of split antennas, in this example, four split antennas 16-1 to 16-4. The high frequency powers after passing the matching circuit 19 from the high frequency power source 18 are distributed to the divided antennas 16-1 to 16-4. In the split antennas 16-1 to 16-4 of this example, a plurality of linear antennas are connected in parallel. In this example, four linear antennas L1a to L1d,... , L4a to L4d are connected in parallel. In addition, since the linear antenna is not a coil antenna but has an inductance component, the linear antennas L1a to L1d,. , L4a to L4d are represented as inductors. And the high frequency antenna circuit of this example has parallel resonant capacitor circuits 30-1 to 30-4 connected in parallel to each of the split antennas 16-1 to 16-4. The parallel resonant capacitor circuits 30-1 to 30-4 include capacitors C1 to C4 therein. Thus, each of the divided antennas 16-1 to 16-4 and each of the parallel resonant capacitor circuits 30-1 to 30-4 constitutes a total of four LC circuits.

As for the value of the inductance L of the split antennas 16-1 to 16-4 and the value of the capacitance C of the parallel resonant capacitor circuits 30-1 to 30-4, the LC circuit resonates in parallel and the split antenna ( It is set to the value through which the maximum loop current flows through 16-1 to 16-4, or that the loop current sufficiently flows through the split antennas 16-1 to 16-4 near the state where the LC circuit is in parallel resonance. .

The equation of parallel resonance is as shown in the following equation.

In Equation 1, L is inductance, C is capacitance, and ω is each frequency. Each frequency ω = 2πf (f is a frequency).

Conventionally, in an inductively coupled plasma processing apparatus having a split antenna and distributing and supplying a current through a matching circuit from a high frequency power source, in order to form a large induction field in the interior of the processing chamber, it is necessary to increase the current flowing through each split antenna. As a result, a large current must be applied to the matching circuit. When a large current flows through a matching circuit, there exists a situation that the coil and capacitor provided in the matching circuit generate heat, and power loss will increase.

In response to this situation, the inductively coupled plasma processing apparatus according to the embodiment connects the parallel resonant capacitor circuits 30-1 to 30-4 to each of the split antennas 16-1 to 16-4 in parallel. . Using these parallel resonant capacitor circuits 30-1 to 30-4, when performing plasma processing, the split antennas 16-1 to 16-4 and the parallel resonant capacitor circuits 30-1 to 30-4 are used. The included LC circuit is placed in parallel resonance or in a state close to the parallel resonance. As a result, a loop current flows through the LC circuit. As a result of the loop current flowing through the LC circuit, a large current can flow through the split antennas 16-1 to 16-4 even if the current flowing through the matching circuit 19 is reduced. By reducing the current flowing through the matching circuit 19, the current values flowing through the coils Lmatch, the capacitors C1match, and C2match provided inside the matching circuit 19 can be reduced, and these heat generations can be suppressed.

Therefore, according to the inductively coupled plasma processing apparatus having the divided antenna according to the embodiment, the inductively coupled plasma processing is provided with the divided antenna and divides and supplies current from the high frequency power supply through the matching circuit while suppressing heat generation of the matching circuit. A high frequency antenna circuit and an inductively coupled plasma processing apparatus capable of forming a sufficient induction electric field in the processing chamber of the apparatus can be obtained.

In the above embodiment, the capacitors C1 to C4 included in the parallel resonant capacitor circuits 30-1 to 30-4 were capacitively fixed. However, the capacitors C1 to C4 are not limited to the capacitance fixed type, but may be the variable capacitance capacitors VC1 to VC4 as shown in FIG. 4. When the variable capacitance capacitors VC1 to VC4 are used, the capacitances of the parallel resonant capacitor circuits 30-1 to 30-4 can be adjusted independently of each of the split antennas 16-1 to 16-4. This makes it possible to adjust the state of parallel resonance for each of the split antennas 16-1 to 16-4.

In addition, the capacitive variable capacitors VC1 to VC4 have a higher price than the capacitive fixed capacitors C1 to C4. For this reason, when the price of an inductively coupled plasma processing apparatus is to be kept low, the capacitive fixed capacitors C1 to C4 may be selected as the capacitors of the parallel resonant capacitor circuits 30-1 to 30-4.

On the other hand, when the intensity of the induction electric field formed in the processing chamber 4 is adjusted to control the plasma distribution in the processing chamber 4, etc., the parallel resonant capacitor circuits 30-1 to 30-4 are used. The capacitors of the variable capacitance capacitors VC1 to VC4 may be selected as the capacitor.

In addition, as shown in FIG. 5, between the current distribution point N1 in the feed path and the distribution point side connection point N2 of the split antennas 16-1 to 16-4 and the parallel resonant capacitor circuits 30-1 to 30-4. The variable capacitance capacitors VCa to VCd for distribution current control may be provided. When the variable capacitance capacitors VCa to VCd for distribution current control are provided, they are independent for each of the division antennas 16-1 to 16-4 to adjust the distribution currents supplied to the division antennas 16-1 to 16-4, respectively. Can be. Even by adjusting the distribution current, the intensity of the induction electric field formed in the processing chamber 4 can be adjusted for each of the split antennas 16-1 to 16-4, for example, to be generated inside the processing chamber 4. It is possible to control the plasma distribution.

Of course, the variable capacitance capacitors VCa to VCd for distribution current control can be used in combination with the variable capacitance capacitors VC1 to VC4 for parallel resonance control shown in FIG. 4. When used together, it is possible to independently control the distribution current and the parallel resonance, so that, for example, the advantage that the plasma distribution can be controlled more accurately can be obtained.

In addition, the plasma distribution inside the processing chamber 4 has an optimum distribution for each application. For example, the storage unit 52 stores the capacitance values of the capacitive variable capacitors VC1 to VC4 or the capacitive values of the capacitive variable capacitors VCa to VCd, or both of them, which are optimal plasma distribution for each application. According to this, the capacitance variable capacitors VC1 to VC4 or the capacitance variable capacitors VCa to VCd or both capacitance values are adjusted. In this way, by using one inductively coupled plasma processing apparatus, an optimum plasma distribution is formed inside the processing chamber 4 for each application, thereby enabling plasma processing.

In addition, as shown in FIG. 6, the divided antennas may not be divided for each of the divided metal windows 2-1 to 2-4. In the example shown in FIG. 6, five split antennas 16-1 to 16-5 are provided for the metal windows 2-1 to 2-4. In this example, the division antennas 16-1 to 16-4 are arranged at the periphery of the top plate of the processing chamber 4, and the division antennas 16-5 are arranged at the center of the processing chamber 4. In addition, as shown in the circuit diagram of FIG. 7, parallel resonant capacitor circuits 30-1 to 30-5 are connected in parallel to each of the split antennas 16-1 to 16-5.

In this manner, the above-described advantages can be obtained even if the divided antennas 16-1 to 16-5 are not divided for each of the metal windows 2-1 to 2-4.

In addition, in the split antenna shown in Fig. 2A, as shown in Fig. 8, for example, parallel resonant with split antennas 16-1 to 16-4 and split antennas 16-1 to 16-4. The ammeter 40 may be provided between the ground point side connection point N3 of the capacitor circuits 30-1 to 30-4. Using the ammeter 40, the current value actually flowing through the split antennas 16-1 to 16-4 is monitored, and this monitoring result is fed back to the capacitive variable capacitors VCa to VCe for distribution current control. For example, the capacitances of the variable capacitance capacitors VCa to VCe are adjusted so that the plasma distribution inside the processing chamber 4 becomes uniform or the plasma distribution inside the processing chamber 4 is optimal for the application.

With this configuration, the distribution current can be controlled based on the value of the current actually flowing in the split antennas 16-1 to 16-4, and the plasma distribution generated inside the processing chamber 4 can be controlled with higher precision. can do.

In addition, as shown in FIG. 9, when the parallel resonant capacitor circuits 30-1 to 30-4 are provided with the capacitive variable capacitors VC1 to VC4, the result of monitoring by the ammeter 40 is resonated. The feedback may be fed back to the variable capacitance capacitors VC1 to VC4 for control. In this case, the parallel resonant capacitor circuits 30-1 to 30-4 and the split antennas 16-1 to 16-4 are based on the values of currents actually flowing through the split antennas 16-1 to 16-4. Can be controlled so that the plasma distribution inside the processing chamber 4 becomes uniform or the plasma distribution inside the processing chamber 4 is optimal for the application. The current flowing through the split antenna can be controlled.

In addition, although not shown in particular, the monitoring result by the ammeter 40 is fed back to the capacitive variable capacitors VC1 to VC4 for resonance state control and the variable variable capacitors VCa to VCd for distribution current control, so that the resonance state of the LC circuit and It is also possible to control both of the distribution currents. In this case, the controllability to control the plasma distribution inside the processing chamber 4 to be uniform or the plasma distribution inside the processing chamber 4 to be the optimum distribution for the application can be further improved.

In addition, although the case where the division antenna is divided into four in FIG. 8 and FIG. 9 was demonstrated, when the division antenna is divided into five as shown in FIG. 6, an ammeter is similarly provided and a current value is measured, It goes without saying that the distribution of the plasma density can be controlled by controlling the variable capacitance capacitors.

In addition, as shown in FIG. 6, when the division antenna is divided into the division antenna 16-5 at the center of the ceiling plate and the division antennas 16-1 to 16-4 at the periphery of the ceiling plate, FIG. As shown in the figure, for example, the variable capacitance capacitor VCe may not be provided in the split antenna 16-5 in the central portion near the current supply unit.

Similarly, as shown in Fig. 11, only the parallel resonant capacitor circuit 30-5 connected in parallel to the split antenna 16-5 in the center portion can be set as the capacitance fixed capacitor C5.

In this way, the current value actually flowing to the split antenna 16-5 in the center can be determined from the ratio with the current value flowing to the other split antennas 16-1 to 16-4, and the split antenna 16- at the peripheral portion can be determined. The distribution current to 1 to 16-4, the resonance state in each LC circuit, or both can be controlled. For this reason, the number of the variable capacitance capacitors can be reduced, and the distribution current based on the current value actually flowing through the split antennas 16-1 to 16-4, or the resonance state in each LC circuit, or both control thereof, The advantage that it can carry out with a simpler structure can be obtained.

In addition, as shown in FIG. 2B, the periphery is divided into eight divisions of the division antennas 16-1 to 16-8, and the nine divisions having a 3 × 3 lattice pattern as a whole are combined with the central division antenna 16-9. 2C or 25-divided into 5 x 5 lattice shapes of the divided antennas 16-1 to 16-25 as shown in FIG. 2C, the center divided antennas 16-9 or 16- likewise are used. A capacitor connected in parallel to 25) can be used as a capacitance fixed capacitor, and a capacitor connected in parallel to another divided antenna can be used as a variable capacitor. The same modification can also be applied to the case of dividing into more than 25 and having a split antenna at the center. In addition, when it is not necessary to be concerned with the fact that the divided antenna to which the capacitive fixed capacitor as a reference is connected in parallel is in the center, the divided antenna is divided into an even number such as 4x2 division or 4x4x16 division. Even if there is no, the above modification can be applied.

In addition, in the said embodiment, although the metal window 2 was used as the top plate of the process chamber 4, it is also possible to use a dielectric window, for example, a window made of quartz as the top plate of the process chamber 4.

In the case where the dielectric windows 2a-1 to 2a-4 are used for the ceiling plate of the processing chamber 4, as shown in FIG. 12, the divided antennas 16-1 to 16-4 are not linear antennas, but are spiral. You can do it with an antenna. In the case of a spiral antenna, as shown in the circuit diagram of Fig. 13, the divided antennas 16-1 to 16-4 are each composed of one coil L1 to L4. For this reason, the number of antennas becomes small compared with the case where several linear antennas are connected in parallel, and the electric current which flows through the matching circuit 19 becomes small. However, in each of the divided antennas 16-1 to 16-4, there is no change in the distribution of current from the high frequency power source 18 through the matching circuit 19. For this reason, even if the split antennas 16-1 to 16-4 are each composed of one spiral antenna, the matching circuits (parallel circuits 30-1 to 30-4 are connected in parallel to the spiral antenna). The current flowing in 19 can be further reduced, and the above-described advantages can be obtained. The advantage of this is that the number of divisions of the divided antennas is "3x3 = 9", "4x4 = 16", "5x5 = 25" from "2x2 = 4" as in the present embodiment. ,… As it increases, it gets better.

In addition, the dielectric windows 2a-1 to 2a-4 are stacked on the support shelf 5 and the support beam 6 without interposing the insulator 10 as shown in FIG. 12.

Although not particularly shown, when the dielectric window is used for the ceiling plate, the dielectric window itself may not be divided.

12 and 13 can be used in combination with the examples shown in FIGS. 4 to 11.

In addition, although the division antenna divided into four or more was demonstrated in detail in this embodiment, it is not limited to these, The division antenna divided into two or three also applies similarly if it divides into two or more. Can be.

Moreover, ashing, etching, CVD film-forming, etc. are mentioned as a plasma process which an inductively coupled plasma processing apparatus performs.

In addition, although a FPD board | substrate was used as a to-be-processed substrate, it is applicable also when processing another board | substrate, such as a semiconductor wafer, as a to-be-processed substrate.

One; Processing chamber
16; High frequency antenna (plasma generating antenna)
16-1 to 16-5; Split antenna
18; High frequency power source
19; Matching circuit
30-1 to 30-5; Parallel resonant capacitor circuit

Claims (14)

An inductively coupled plasma processing apparatus comprising: a high frequency antenna circuit for generating an inductively coupled plasma in a processing chamber for processing a substrate,
A plasma generating antenna generating plasma in the processing chamber;
A high frequency power supply for supplying high frequency power to the plasma generating antenna;
A matching circuit interposed between the high frequency power supply and the plasma generating antenna;
A plurality of split antennas constituting the plasma generating antenna, wherein high frequency power is distributed after passing through the matching circuit;
And a parallel resonant capacitor circuit provided in parallel to each of said plurality of divided antennas. An inductively coupled plasma processing apparatus for generating an inductively coupled plasma in a processing chamber for processing a substrate,
A ceiling plate installed above the processing chamber;
A plasma generation antenna provided on the ceiling plate and configured of a plurality of split antennas;
And a parallel resonant capacitor circuit provided in parallel with each of said plurality of split antennas. The inductively coupled plasma processing apparatus according to claim 2, wherein the ceiling plate is made of a metal plate divided equally with the plurality of divided antennas. The inductively coupled plasma processing apparatus according to claim 3, wherein the plurality of split antennas are formed in parallel in a plurality of parallel lines corresponding to the divided metal plates, respectively. The inductively coupled plasma processing apparatus according to claim 2, wherein the ceiling plate is composed of at least one dielectric plate. The inductively coupled plasma processing apparatus according to claim 5, wherein the plurality of split antennas are each formed in a spiral shape. The inductively coupled plasma processing apparatus according to any one of claims 2 to 6, wherein at least one of the parallel resonant capacitor circuits includes a capacitive fixed capacitor connected in parallel to the split antenna. The inductive coupling according to any one of claims 2 to 6, wherein at least one of the parallel resonant capacitor circuits includes a capacitive variable capacitor for resonance state control connected in parallel to the split antenna. Plasma processing apparatus. 7. The variable capacitance type according to any one of claims 2 to 6, wherein a current distribution point for distributing current to the split antenna and a connection point on the split point side of the split antenna and the parallel resonant capacitor circuit are provided. An inductively coupled plasma processing apparatus, further comprising a capacitor. The method of claim 8, wherein the split antenna comprises a split antenna disposed at the center of the ceiling plate, and a split antenna disposed at the periphery of the ceiling plate,
An inductively coupled plasma processing apparatus, wherein the variable capacitance capacitor for controlling the resonance state is provided in a split antenna disposed at a periphery of the ceiling plate. The split antenna according to claim 9, wherein the split antenna includes a split antenna disposed at the center of the ceiling plate and a split antenna disposed at the periphery of the ceiling plate.
The capacitive variable capacitor for controlling the distribution current is provided in a split antenna disposed at the periphery of the ceiling plate. The split antenna according to claim 9, wherein the split antenna includes a split antenna disposed at the center of the ceiling plate and a split antenna disposed at the periphery of the ceiling plate.
The inductively coupled plasma processing apparatus, wherein the variable capacitance capacitor for controlling the resonance state and the variable capacitance capacitor for controlling the distribution current are provided in a split antenna disposed at the periphery of the ceiling plate. According to claim 8, further comprising an ammeter provided between the split antenna and the ground point,
Inductive coupling, characterized in that for feeding back the monitoring result by the ammeter to the capacitive variable capacitor for controlling the resonance state, the resonance state of the LC circuit including the split antenna and the parallel resonance capacitor circuit is controlled. Plasma processing apparatus. 10. The method of claim 9, further comprising an ammeter disposed between the split antenna and the ground point,
Inductively coupled plasma processing apparatus, characterized in that for controlling the distribution current to the divided antenna by feeding back the monitoring result by the ammeter to the variable capacitance capacitor for controlling the distribution current.

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