KR20130047532A - Apparatus and method for treating substrate - Google Patents

Abstract

PURPOSE: Substrate processing apparatus and impedance matching method are provided to quickly match impedance by compensating attenuated impedance variation in a matching circuit through a transformer although impedance varies in a wide range in a process chamber. CONSTITUTION: A substrate processing apparatus(100) includes a process chamber(1000), a high frequency power supply(2000), an impedance matching apparatus(3000) and a transmission line(110). The high frequency power supply generates high frequency power. The process chamber performs a plasma process using the high frequency power. The matching circuit compensates varying impedance of the process chamber. The transformer is arranged in between the process chamber and matching circuit and attenuates the impedance of the process chamber. [Reference numerals] (1000) Process chamber; (2000) High frequency power supply; (3000) Impedance matching apparatus

Description

Substrate Processing Equipment and Impedance Matching Method {APPARATUS AND METHOD FOR TREATING SUBSTRATE}

The present invention relates to a substrate processing apparatus and an impedance matching method, and more particularly, to a substrate processing apparatus and an impedance matching method for matching impedance during a plasma process.

Impedance matching is essential because high frequency power is used to generate plasma in a plasma process in which a substrate is treated with plasma. Impedance matching is to adjust the impedance of the transmitting and receiving end of the power in the same way in order to effectively transmit power, the plasma process requires impedance matching between the power supply for providing high-frequency power and the chamber to generate and maintain the plasma.

Since the impedance of the plasma is determined by various variables including the type, temperature, and pressure of the source gas, the impedance of the chamber changes continuously during the process. Therefore, the matching of the impedance in the plasma process is performed by compensating for the impedance of the chamber which is changed into a matching circuit having a circuit composed of a capacitor or an inductor.

However, since there is a limit in response speed for adjusting impedance by adjusting capacitance or inductance, a time delay occurs in impedance matching. Particularly, when the impedance of the chamber is changed to a large width as the plasma is generated at the beginning of the process, it rapidly changes. In this case, an arc is generated in the chamber due to the reflected wave generated by not responding quickly to the impedance of the chamber, and the density of the plasma in the chamber is increased. There is a deviation.

One object of the present invention is to provide a substrate processing apparatus and a substrate processing method for quickly performing impedance matching.

Another object of the present invention is to provide a substrate processing apparatus and a substrate processing method for performing impedance matching on a high frequency power of a wide frequency band.

The problem to be solved by the present invention is not limited to the above-described problem, the objects that are not mentioned will be clearly understood by those skilled in the art from the present specification and the accompanying drawings. .

The present invention provides a substrate processing apparatus.

One aspect of the substrate processing apparatus according to the present invention, a high frequency power source for generating a high frequency power; A process chamber performing a plasma process using the high frequency power; A matching circuit for compensating for the changing impedance of the process chamber; And a transformer disposed between the process chamber and the matching circuit to attenuate the impedance of the process chamber.

The transformer may be a Ruthroff transformer.

The rootloft transformer may be a 1: 4 unbalanced-to-unbalanced transformer.

The substrate processing apparatus includes an impedance measuring instrument for measuring impedance of the process chamber; A reflection power meter for measuring the reflection power; And a controller configured to control the matching circuit based on the measured values of the impedance measuring instrument and the reflected power measuring instrument.

The matching circuit includes a plurality of capacitors arranged in parallel with each other and a plurality of switches connected to the plurality of capacitors, wherein the controller generates a control signal based on the measured values, and the matching circuit includes: According to the control signal, the plurality of switches can be opened and closed.

The matching circuit may be an inverse-L-type circuit.

The process chamber may include a housing providing a space in which the plasma process is performed and a plasma generator providing plasma to the housing using the high frequency power.

The plasma generator may be a capacitively coupled plasma (CCP) generator including a plurality of electrodes spaced apart from each other in the housing.

The high frequency power source, the matching circuit and the transformer are plural, and the high frequency power source generates high frequency power of different frequencies, and the high frequency power of different frequencies is applied to the plurality of electrodes. The matching circuit and the transformer may be connected to each of the applied electrodes.

The present invention provides an impedance matching method.

One aspect of the impedance matching method according to the present invention is a method of matching impedance in a substrate processing apparatus that performs a plasma process using high frequency power, wherein the transformer disposed between the matching circuit and the process chamber is a plasma process. The impedance of the process chamber that changes during the process is attenuated, and the matching circuit compensates for the attenuated impedance to perform impedance matching.

The transformer may be a 1: 4 transformer, and the matching circuit may perform impedance matching by compensating for 1/4 of the change in impedance of the process chamber.

According to the present invention, the matching circuit compensates the amount of impedance change attenuated through the transformer, so that the matching circuit can be quickly matched even if the impedance varies greatly in the process chamber.

According to the present invention, since the impedance matching is made quickly, the delay time is reduced, and the reflected wave can be removed to remove arc discharge from the process chamber, thereby increasing the process efficiency.

According to the present invention, since the root loft transformer is used, impedances can be matched to high frequency power of various frequencies having a wide bandwidth.

The effects of the present invention are not limited to the above-mentioned effects, and the effects not mentioned can be clearly understood by those skilled in the art from the present specification and the accompanying drawings.

1 is a schematic view of a substrate processing apparatus.
2 is a configuration diagram of an embodiment of the substrate processing apparatus of FIG. 1.
3 is a circuit diagram of an embodiment of the matching circuit of FIG. 2.
4 is a circuit diagram of another embodiment of the matching circuit of FIG.
5 is a circuit diagram of another embodiment of the matching circuit of FIG.
6 is a circuit diagram of one embodiment of the transformer of FIG.
7 is a plan view of the transformer of FIG. 6.
FIG. 8 is a diagram illustrating that a plurality of transformers of FIG. 6 are connected.
FIG. 9 is a graph illustrating a change in current by the transformer of FIG. 6.
FIG. 10 is a graph illustrating a change in voltage by the transformer of FIG. 6.
FIG. 11 is a graph illustrating a change in impedance by the transformer of FIG. 6.
12 to 14 are configuration diagrams of modified examples of the substrate processing apparatus of FIG. 1.
FIG. 15 is a graph illustrating impedance matching in the substrate processing apparatus of FIG. 14.

The terms and accompanying drawings used herein are for the purpose of illustrating the present invention easily, and the present invention is not limited by the terms and drawings.

The detailed description of known techniques which are not closely related to the idea of the present invention among the techniques used in the present invention will be omitted.

Hereinafter, the substrate processing apparatus 100 according to the present invention will be described.

The substrate processing apparatus 100 performs a plasma process. The plasma process may be a plasma deposition process, a plasma etching process, a plasma ashing process, a plasma cleaning process, or the like. In such a plasma process, the plasma may be formed by applying high frequency power to the source gas. Of course, the substrate processing apparatus 100 according to the present invention may perform various plasma processes in addition to the above examples.

On the other hand, the substrate here is a comprehensive concept including both a semiconductor device, a flat panel display (FPD) and other substrates used in the manufacture of articles having a circuit pattern formed on a thin film.

1 is a schematic diagram of a substrate processing apparatus 100.

Referring to FIG. 1, the substrate processing apparatus 100 may include a process chamber 1000, a high frequency power supply 2000, an impedance matching apparatus 3000, and a transmission line 110. The process chamber 1000 performs a plasma process using high frequency power. The high frequency power source 2000 generates high frequency power, and the transmission line 110 connects the high frequency power source 2000 and the process chamber 1000 to transmit the high frequency power to the process chamber 1000. The impedance matching device 3000 matches an impedance between the high frequency power supply 2000 and the process chamber 1000.

Hereinafter, an embodiment of the substrate processing apparatus 100 according to the present invention will be described.

2 is a configuration diagram of an embodiment of the substrate processing apparatus 100 of FIG. 1.

The process chamber 1000 includes a housing 1100 and a plasma generator 1200.

The housing 1100 provides a space in which the plasma process is performed.

The plasma generator 1200 provides a plasma to the housing 1100. The plasma generator 1200 generates plasma by applying high frequency power to the source gas.

As the plasma generator 1200, a capacitively coupled plasma generator (CCPG) 1200a may be used. The capacitively coupled plasma generator 1200a may include a plurality of electrodes positioned inside the housing 1100.

For example, the capacitively coupled plasma generator 1200a may include a first electrode 1210 and a second electrode 1220. The first electrode 1210 is disposed above the inside of the housing 1100, the second electrode 1220 is disposed below the inside of the housing 1100, and the first electrode 1210 and the second electrode 1220 It may be arranged up and down parallel to each other. High frequency power may be applied to one of the two electrodes 1210 and 1220 through the transmission line 110, and the other may be grounded and grounded. When high frequency power is applied, a capacitor electric field is formed between the first electrode 1210 and the second electrode 1220. The source gas between the positive electrodes 1210 and 1220 may be ionized by receiving electrical energy from a storage electric field and may be in a plasma state. On the other hand, such a source gas may be introduced into the housing 1100 from an external gas supply source (not shown).

The high frequency power supply 2000 generates high frequency power. Here, the high frequency power source 2000 may generate high frequency power in a pulse mode. The high frequency power supply 2000 may generate high frequency power of a specific frequency. For example, the high frequency power source 1000 may generate power of 2Mhz, 13.56Mhz, and 100Mhz frequency. Of course, the high frequency power supply 2000 may generate high frequency power of a frequency other than the aforementioned frequency.

The transmission line 110 transmits the high frequency power from the high frequency power source 2000 to the process chamber 1000.

As such, when high frequency power is transmitted through the transmission line 110, if the impedances of the transmitting end and the receiving end of the power do not match, a reflected wave may be generated to generate reflected power. In the case of high-frequency power, delay power is generated in non-consumable circuits such as capacitors and inductors during the transmission process, and reflected waves are generated by the phase difference. When such reflected waves occur, not only the power transmission efficiency is lowered, Electric power transmitted from the 2000 to the process chamber 1000 becomes nonuniform, making it difficult to generate a plasma or maintain a uniform density. In addition, when the reflected wave is accumulated in the process chamber 1000, an arc discharge may be induced to directly damage the substrate S.

The impedance matching device 3000 may match the impedance. If the impedance is matched, no reflected wave occurs and power can be transmitted efficiently.

The impedance matching device 3000 may include a matching circuit 3100, a transformer 3200, a controller 3300, an impedance measuring device 3400, and a reflected power measuring device 3500.

The matching circuit 3100 matches the impedance of the process chamber 1000 side and the high frequency power supply 2000 side. The matching circuit 3100 includes circuit elements such as a capacitor or an inductor. All or part of the circuit elements of the matching circuit 3100 may be variable circuit elements.

3 is a circuit diagram of an embodiment of the matching circuit 3100 of FIG.

According to an embodiment, the matching circuit 3100 may include a variable capacitor 3110 and an inductor 3120. Referring to FIG. 3, the variable capacitor 3110 may be connected in parallel on the transmission line 110, and the inductor 3120 may be connected in series. The matching circuit 3100 may adjust the capacitance of the variable capacitor 3110 to match impedance.

The variable capacitor 3110 may include a plurality of capacitors 3111 and a plurality of switches 3112. The plurality of capacitors 3111 may be connected in parallel with each other. The plurality of switches 3112 may be connected to each of the plurality of capacitors 3111, and may be opened and closed under the control of the controller 3300, which will be described later.

The switch 3112 adjusts a short circuit between the capacitor and the high frequency transmission line 110 according to a control signal from the controller 3300. The plurality of capacitors are each connected to a switch 3112 which regulates its short. For example, the controller 3300 may transmit a control signal for controlling a short circuit of each switch 3112, and the switch 3112 may adjust a short circuit of each capacitor accordingly.

Such a switch 3112 may be a digital switch. For example, an RF relay, a pin diode, or a metal-oxide semiconductor field effect transistor (MOSFET) may be used as the switch 3112. Since the digital switch opens and closes the capacitor 3110 corresponding to the ON / OFF signal, the impedance can be compensated with a faster response speed than the mechanically driven switch. Therefore, the response speed of impedance matching can be improved, the delay time can be reduced, and the reflected wave can be eliminated.

The capacitance of the variable capacitor 3110 may be determined by a combination of states of the switch 3112. That is, the capacitance of the variable capacitor 3110 may be determined as the sum of the capacitances of the capacitors 3111 of which the switch 3112 is closed among the capacitors 3111 connected in parallel.

Here, the plurality of capacitors 3111 may all have the same capacitance. Or the plurality of capacitors 3111 each have a ratio of capacitances of 1: 2: 3:... may be provided to be: n. Alternatively, the plurality of capacitors 3111 may have a capacitance ratio of 1:21:22:... May be provided to be: 2n.

Since the total capacitance of the variable capacitor 3110 is composed of a combination of sums of the connected capacitors 3111, if the capacitor 3111 has a capacity according to the above-described value, the capacitance of the variable capacitor 3110 can be easily controlled, and a wide range can be obtained. It can respond.

In the above description, the matching circuit 3100 including one variable capacitor 3110 and the inductor 3120 has been described. However, the types, numbers, and connection relationships of the circuit elements constituting the matching circuit 3100 may be different from each other. have.

4 is a circuit diagram of another embodiment of the matching circuit 3100 of FIG. 2, and FIG. 5 is a circuit diagram of another embodiment of the matching circuit 3100 of FIG. 2.

Referring to FIG. 4, the matching circuit 3100 includes an L capacitor including a variable capacitor 3110a connected in parallel to the transmission line 110, a capacitor 3110b connected in series, and an inductor 3120. It can be implemented as a circuit of. Referring to FIG. 5, the matching circuit 3100 is a pie type (π type) circuit including an inductor 3120 and a variable capacitor 3110a and a capacitor 3110b connected in parallel to the transmission line 110. Can be implemented. Of course, the matching circuit 3100 may be implemented as an inverse L type circuit, various known circuits, and a circuit appropriately modified as necessary in addition to the above examples.

The transformer 3200 is installed on the transmission line 110 to convert the impedance of the input side and the output side.

FIG. 6 is a circuit diagram of one embodiment of the transformer 3200 of FIG. 2, and FIG. 7 is a plan view of the transformer 3200 of FIG. 6.

Referring to FIG. 6, a root loft transformer may be used as the transformer 3200. The root loft transformer has the advantage of being capable of impedance conversion over a wide bandwidth and excellent transmission efficiency. 6 and 7 illustrate 1: 4 unbalanced-to-unbalanced rootloft transformers. As shown in FIG. 7, the 1: 4 rootloft transformer may be manufactured by winding a twisted line around an annular core using the bootstrap principle. At this time, when the values of the first coil L1 and the second coil L2 are the same, the conversion ratio of the impedance of the output side to the input side becomes 1: 4.

In this root loft transformer, increasing the number of twisted turns around the core changes the conversion ratio of the impedance. Rootloft transformers operate as 1: 2.25 untransformers for three-line twists and have a conversion ratio of 1: 1.78 for four-line twists.

On the other hand, if the root loft transformer is connected in series can have a larger conversion ratio.

FIG. 8 illustrates that a plurality of transformers 3200 of FIG. 6 are connected.

Referring to FIG. 8, when two 1: 4 unary root loft transformers are arranged in series, the conversion ratio of the primary output side to the input side has a conversion ratio of 1: 4 to the primary output side is 1: 4. As a result, the impedance conversion ratio of the final output side to the input side may be 1:16.

In the substrate processing apparatus 100, the transmission line 110 may be connected to the process chamber 1000 from the high frequency power supply 2000, and the matching circuit 3100 and the transformer 3200 may be connected therebetween. That is, the transmission line 110 may connect the high frequency power source 2000, the matching circuit 3100, the transformer 3200, and the process chamber 1000 in this order.

Accordingly, the high frequency power supply 2000 and the matching circuit 3200 may be disposed on the input side of the transformer 3200, and the process chamber 1000 may be placed on the output side of the transformer 3200. Accordingly, the transformer 3200 may attenuate the impedance of the process chamber 1000.

In general, the high frequency power supply 2000 has a fixed impedance, for example 50 Ohm, while the process chamber 1000 has an impedance ranging from a few Ohm to as high as 300 Ohm during the plasma process. When the impedance of the process chamber 1000 is transmitted to the input side through the transformer 3200, the impedance of the process chamber 1000 is reduced in the matching circuit 3100 connected to the input side because the 1: 4 untransformer is attenuated to about 70 Ohm. Even if the width is changed to several hundred Ohm, the impedance can be matched between the process chamber 1000 and the high frequency power supply 2000 by adjusting the impedance only by the reduction ratio according to the conversion ratio.

In particular, in the initial stage of the plasma process, while the plasma is generated by the high-speed pulse while the process chamber 1000 is supplied with power in a pulse mode, the impedance changes largely. The matching circuit 3100 is attenuated by the transformer 3200. Since the impedance can be matched by compensating the impedance of the changed range, the matching speed of the impedance can be improved.

FIG. 9 is a graph illustrating a change in current by the transformer 3200 of FIG. 6. FIG. 10 is a graph illustrating a change in voltage by the transformer 3200 of FIG. 6, and FIG. 11 is a graph illustrating a change in impedance by the transformer 3200 of FIG. 6.

9 to 10, in the case of using the 1: 4 union root loft transformer, the current and voltage values are doubled in the high frequency power supply 2000 side compared to the process chamber 1000 in the case of the high frequency power supply having a frequency of 2 Mhz. It can be seen that the impedance is attenuated to 1/4.

However, the transformer 3200 is not necessarily limited to the above-described example, and the root loft transformer may be replaced with a transformer that performs other functions similar or similar thereto.

The controller 3300 generates a control signal for impedance compensation based on the measured values of the impedance measuring device 3400 and the reflected power measuring device 3500 and sends the control signal to the matching circuit 3100 to control the matching circuit 3100. Here, the impedance measuring unit 3400 measures the impedance of the process chamber 1000 and transmits the measured value to the controller 3300. In addition, the reflected power measuring device 3500 measures the reflected power by the reflected wave, and transmits the measured value to the controller 3300.

For example, the control signal may be a control signal for turning on and off the plurality of switches 3120 of the matching circuit 3100. In the matching circuit 3100, the capacitance may be adjusted while the switch 3120 is opened and closed according to a control signal.

Such a controller 3300 may be implemented in a computer or similar device using hardware, software, or a combination thereof.

In hardware, the controller 3300 may include application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), and processors (processors). It can be implemented as micro-controllers, microprocessors, or electrical devices that perform similar control functions.

In addition, in software, the controller 3300 may be implemented by software code or software application written in one or more programming languages. The software is executed by a hardware-implemented control unit. The software may be installed by being transmitted from an external device such as a server in the hardware configuration described above.

In the above description, the substrate processing apparatus 100 has been described with reference to the process chamber 1000 including the capacitively coupled plasma generator 1200a to which high frequency power of a single frequency is applied. However, the substrate processing apparatus 100 is different from this. It may be configured to.

12 to 14 are configuration diagrams of modified examples of the substrate processing apparatus 100 of FIG. 1.

Referring to FIG. 12, in the substrate processing apparatus 100, an inductively coupled plasma generator (ICPG) 1200b may be used instead of the capacitively coupled plasma generator 1200a in the process chamber 1000. The inductively coupled plasma generator 1200b may be installed at a portion where the source gas flows into the process chamber 1000 to form an induction electric field. Accordingly, the source gas flowing into the process chamber 1000 may be ionized by an induction electric field to be in a plasma state.

In addition, in the substrate processing apparatus 100, the process chamber 1000 may simultaneously perform a plasma process using high frequency power having different frequencies. In the case of the plasma etching process, if the plasma process is performed using a plurality of different high frequency powers, an etching effect superior to that of using a single frequency high frequency power may be obtained.

Referring to FIG. 13, in the substrate processing apparatus 100, both electrodes 1210a and 1210b of the capacitively coupled plasma generator 1200a are connected to two high frequency power sources 2000a and 2000b that generate high frequency power at different frequencies. Each can be connected. Accordingly, different high frequency powers are applied to the first electrode 1210a and the second electrode 1210b to simultaneously perform a plasma process using high frequency power of two different frequencies.

Referring to FIG. 14, three or more different frequencies may be used in the substrate processing apparatus 100. For example, in the process chamber 1000, a first electrode 1210a may be disposed above the housing 1100 and spaced below the second electrode 1210b and a third electrode 1210c. . In this case, high frequency power sources 2000a, 2000b, and 2000c generating different first high frequency powers, second high frequency powers, and third high frequency powers may be connected to the electrodes 1210a, 1210b, and 1210c, respectively. Accordingly, the plasma processing may be performed by three high frequency powers at the same time in the process chamber 1000. For example, the first high frequency power, the second high frequency power, and the third high frequency power may be 2Mhz, 13.6Mhz, and 100Mhz, respectively. In some cases, the second electrode 1210b and the third electrode 1210c may be integrally provided.

In the case of using a wide bandwidth at the same time it is difficult to predict the change in impedance, it is difficult to match the impedance because the bandwidth is different, the root loft transformer can be effectively used because the impedance can be converted over a wide bandwidth.

FIG. 15 is a graph illustrating impedance matching in the substrate processing apparatus 100 of FIG. 14.

Referring to FIG. 15, it can be seen that when a 1: 4 unlanguage loop loft transformer is used, impedances are simultaneously matched to a fixed impedance of 50 Ohm at the high frequency power supply 2000 side for three bandwidths of 2Mhz, 13.6Mhz, and 100Mhz.

Hereinafter, an impedance matching method using the substrate processing apparatus 100 according to the present invention will be described. However, the impedance matching method may be performed using the same or similar other device in addition to the substrate processing apparatus 100 described above. In addition, the impedance matching method may be stored in a computer-readable recording medium in the form of a code or a program for performing the impedance matching method.

In the impedance matching method, the source gas is first introduced into the process chamber 1000 from a gas supply source (not shown). When the source gas is introduced, the high frequency power source 1000 generates high frequency power, and the high frequency power is transmitted to the plasma generator 1200 through the transmission line 110. The plasma generator 1200 ionizes the source gas using high frequency power to form a plasma. When the plasma is formed, the process chamber 1000 processes the substrate using the plasma. As described above, the plasma impedance or the plasma impedance may be changed by various process conditions such as foreign matters generated from the substrate in the process of generating the plasma and processing the substrate, the density of the plasma, the type of the source gas, and the internal temperature and the internal pressure of the process chamber 1000. The impedance of the process chamber 1000 is changed. In particular, in the initial stage of the plasma process of supplying high frequency power in the pulse mode, its impedance may change rapidly.

The impedance measurer 3400 measures the impedance of the process chamber 1000 and applies the measured value to the controller 3300. In addition, as impedance changes, impedance matching may be broken and reflected waves may be generated. The reflected power measuring device 3500 measures the reflected power of the high frequency power supply 2000 and applies the measured value to the controller 3300.

The controller 3300 obtains measurement values from the impedance measuring device 3400 and the reflected power measuring device 3500 to generate a control signal, and transmits the generated control signal to the matching circuit 3100.

In the matching circuit 3100, the plurality of switches 3112 are opened or closed according to the control signal. The variable capacitor 3110 has its capacitance adjusted by the sum of the capacitances of the capacitors 3111 connected to the closed switch 3112 of the plurality of switches 3112. As a result, impedance matching between the high frequency power supply 2000 and the process chamber 1000 may be performed. However, the circuit configuration of the matching circuit 3100 is not limited to the variable capacitor 3110, and in other configurations, similarly, the impedance may be compensated according to the control signal.

In the matching process of the impedance, the controller 3300 transmits a digital signal, and the digital switch 3112 implemented as a diode or a transistor is turned on and off according to the control signal, and thus the impedance is faster than the mechanical drive switch. You can compensate.

Here, the matching circuit 3100 may match the impedance by compensating for the amount of change that is attenuated through the transformer 3200 instead of the amount of change of impedance that is actually changed in the process chamber 1000. The transformer 3200 may be disposed between the matching circuit 3100 and the process chamber 1000 to attenuate the impedance of the process chamber 1000 with respect to the matching circuit 3100 side. When a 1: 4 unified root loft transformer is used, the impedance of the process chamber 1000 is attenuated to 1/4. Accordingly, the matching circuit 3100 may match the impedance by compensating an impedance of 1/4 of the impedance change amount of the process chamber 1000.

In particular, since the impedance of the process chamber 1000 changes rapidly in the process of supplying power in the initial pulse mode of the plasma process, even when the matching circuit 3100 uses a digital switch, a minimum delay time may occur. As such, the impedance change width is attenuated and the response speed of the matching circuit 3200 is improved, thereby minimizing the generation of reflected waves.

The above-described embodiments of the present invention are described in order to facilitate understanding of the present invention to those skilled in the art, so the present invention is not limited to the above embodiments.

Therefore, it is to be understood that the present invention may be embodied in many other specific forms without departing from the spirit or essential characteristics thereof. For example, the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. All of the modifications are included.

In addition, the scope of protection of the present invention should be construed according to the following claims, and all inventions within the scope of the claims should be construed as being included in the scope of the present invention.

100: substrate processing apparatus
1000: high frequency power
110: transmission line
1000: process chamber
1100: housing
1200: plasma generator
1210: electrode
3000: Impedance Matching Device
3100: matching circuit
3200: transformer
3300: controller
3400: Impedance Meter
3500: reflected power meter

Claims (11)

A high frequency power source generating high frequency power;
A process chamber performing a plasma process using the high frequency power;
A matching circuit for compensating for the changing impedance of the process chamber;
A transformer disposed between the process chamber and the matching circuit to attenuate the impedance of the process chamber;
Substrate processing apparatus. The method of claim 1,
The transformer is a Ruthroff transformer
Substrate processing apparatus. The method of claim 2,
The rootloft transformer is a 1: 4 unbalanced-to-unbalanced transformer
Substrate processing apparatus. 4. The method according to any one of claims 1 to 3,
An impedance measuring instrument for measuring impedance of the process chamber;
A reflection power meter for measuring the reflection power; And
And a controller for controlling the matching circuit based on the measured values of the impedance measuring instrument and the reflected power measuring instrument.
Substrate processing apparatus. 5. The method of claim 4,
The matching circuit includes a plurality of capacitors disposed in parallel with each other and a plurality of switches connected to the plurality of capacitors, respectively.
The controller generates a control signal based on the measured values,
The matching circuit opens and closes the plurality of switches according to the control signal.
Substrate processing apparatus. 4. The method according to any one of claims 1 to 3,
The matching circuit is an inverse-L-type circuit.
Substrate processing apparatus. 4. The method according to any one of claims 1 to 3,
The process chamber includes a housing providing a space in which the plasma process is performed and a plasma generator providing plasma to the housing using the high frequency power.
Substrate processing apparatus. The method of claim 7, wherein
The plasma generator is a capacitively coupled plasma (CCP) generator including a plurality of electrodes spaced apart from each other inside the housing.
Substrate processing apparatus. 9. The method of claim 8,
The high frequency power source, the matching circuit and the transformer are plural,
The high frequency power source generates high frequency power of different frequencies,
The high frequency power of the different frequencies is applied to the plurality of electrodes,
The matching circuit and the transformer are connected to each electrode to which the high frequency power is applied.
Substrate processing apparatus. In the method of matching the impedance in the substrate processing apparatus performing a plasma process using a high frequency power,
A transformer disposed between the matching circuit and the process chamber attenuates the impedance of the process chamber that changes during the plasma process, and the matching circuit compensates for the attenuated impedance to perform impedance matching.
Impedance matching method. The method of claim 10,
The transformer is a 1: 4 transformer,
The matching circuit performs impedance matching by compensating for 1/4 of the change in impedance of the process chamber.
Impedance matching method.

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