KR101490415B1 - Apparatus and method for plasma treatment - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma processing apparatus and a processing method for performing a predetermined process on a substrate by using plasma, and by optimally designing factors affecting the plasma processing process, And a plasma processing apparatus and a processing method capable of preventing deformation and breakage of a substrate or each of components.

Plasma treatment, electrostatic chuck

Description

[0001] APPARATUS AND METHOD FOR PLASMA TREATMENT [0002]

TECHNICAL FIELD [0001] The present invention relates to a plasma processing apparatus and a plasma processing method for performing predetermined processing using a plasma on a substrate to be processed.

2. Description of the Related Art Generally, in a manufacturing process of a semiconductor wafer, a thin film transistor (TFT) or a glass substrate (hereinafter, referred to as a substrate) used for a flat panel display, a substrate transferred into a process chamber is fixed And a predetermined processing is performed on the fixed substrate using a plasma in a vacuum atmosphere.

2. Description of the Related Art In the field of semiconductors, circuit integration and lightening have been progressed in recent years, and the area of manufacture of a flat panel display device is becoming larger. Accordingly, the importance of the technique of accurately fixing the substrate to the processing position is emphasized.

Techniques for fixing the substrate to the processing position in the process chamber include a method using a clamp, a method using vacuum pressure, or an electrostatic chuck (ESC) And a method of using an electrostatic chuck having an excellent process uniformity is increasingly applied. The fixing method of the substrate using the electrostatic chuck prevents the damage of the substrate and reduces the defect rate of the product because the substrate is adsorbed by using the electrostatic force.

1, a conventional electrostatic chuck includes a base member 1 positioned at the lowermost part thereof, and an upper insulating layer (not shown) disposed on the upper side of the base member 1 and coated with ceramics whose surface is an insulator, respectively 2 and a lower insulating layer 3 and an electrode pattern 4 provided between the upper insulating layer 2 and the lower insulating layer 3 and to which a predetermined power source is applied, ), The upper insulating layer 2 and the lower insulating layer 3 are firmly attached to each other by an adhesive material.

The upper surface of the upper insulating layer 2 is provided with a plurality of protrusions 5 arranged at predetermined intervals and the substrate S is seated on the upper side of the protrusions 5. [ A space between the upper insulating layer 2 and the substrate S is supplied with a cooling gas for cooling the substrate S during the plasma processing process of the substrate S.

A direct current power of approximately -1000 V to +1000 V is applied to the electrode pattern 4 to generate an electrostatic force due to polarization at the surface of the substrate S and the upper insulating layer 2, The substrate S is chucked by the electrostatic chuck by the electrostatic force.

The degree to which the substrate S is processed in the plasma processing apparatus using the electrostatic chuck is affected by various factors. These factors include the pressure inside the process chamber, the chucking force that the substrate S is attracted to the electrostatic chuck, the formation state of the plasma during the process, the temperature of the substrate S during the process, And a separation step.

First, in relation to the chucking force of the substrate S, the electrostatic chuck fixes the substrate S by the electrostatic force generated by the voltage applied to the electrode pattern 4, The size of the voltage applied to the pattern 4 and the height of the space between the substrate S and the upper insulator 2.

The temperature of the substrate S can be raised because the plasma has a low pressure or a high temperature and the substrate S is exposed to the plasma with respect to the temperature of the substrate S, There is a risk of deformation or breakage of the substrate S. Accordingly, the cooling gas is supplied to the space between the substrate S and the upper insulator 2 to prevent the temperature of the substrate S from becoming excessively high.

A cooling gas supply device is provided as a supply source of the cooling gas to the outside of the process chamber for supplying the cooling gas and a supply for supplying the cooling gas to the space between the substrate S and the upper insulator 2 and the cooling gas supply device And a valve for controlling the supply amount of the cooling gas on the supply passage.

The supply of the cooling gas is closely related to the chucking force of the substrate S. When the chucking force of the substrate S is weak and the supplied amount of the cooling gas is large, And the cooling gas may leak from the space between the electrostatic chuck and the substrate S. As a result, the cooling efficiency of the substrate S may be deteriorated.

Regarding the formation state of the plasma, the plasma in the process chamber is supplied with a reaction gas into the process chamber, and at the same time, a high frequency voltage is applied to a pair of electrodes disposed inside the process chamber to form a high frequency electric field The formation state of the plasma can be controlled by adjusting the voltage applied to the electrode, and the formation state of the plasma can be determined from the voltage value sensed by the voltage sensor and the waveform thereof.

However, in the conventional electrostatic chuck, a current leaks through the electrostatic chuck even when the electrostatic chuck is in an insulated state during a process of plasma processing, There is a problem that the applied voltage becomes small in size and the substrate S can not be suitably chucked on the electrostatic chuck.

In addition, when the chucking of the substrate S is not properly performed, the cooling gas leaks out, so that the cooling action is not smoothly performed and the temperature of the substrate S rises. As a result, There is a problem that the substrate S is damaged as well as the surface of the substrate S.

In order to solve such a problem, a method of increasing the chucking force of the substrate S by increasing the degree of application of the DC power may be considered. In such a case, however, since the chucking force of the substrate S becomes large, S is deformed or broken, and the amount of leakage current from the electrostatic chuck increases due to an excessive voltage, so that the electrostatic chuck is broken.

When the electrostatic chuck is broken, an arcing phenomenon occurs between the substrate S and the electrostatic chuck, and a hole is formed in the substrate S by the arcing phenomenon. When a hole is formed in the substrate S, There is a problem that plasma is concentrated on the surface of the substrate, and thus various parts including the electrode are damaged.

On the other hand, in the plasma process using the electrostatic chuck, even if the power applied to the electrode pattern 4 is cut off, the charges on the electrode pattern 4 remain unremoved, thereby reducing the efficiency of the electrostatic chuck and shortening the service life There is a problem.

The electrostatic force is set in accordance with the material of the substrate S and the thickness of the substrate S. If a uniform electrostatic force can not be maintained between a plurality of insulators, an electrostatic force error occurs, The substrate S may not be properly separated from the electrostatic chuck at the time of separating the substrate S from the substrate S, resulting in sticking phenomenon, or deformation and cracking of the substrate S, .

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of applying a voltage and a method of supplying a cooling gas to an electrode pattern of an electrostatic chuck in a plasma processing apparatus, And a plasma processing apparatus and a processing method capable of improving the plasma processing condition of the substrate.

It is another object of the present invention to provide a plasma processing apparatus capable of detecting the amount of leakage current, the supply amount of the cooling gas, and the formation state of the plasma sensed by the voltage sensor, And to provide a plasma processing apparatus and a processing method capable of preventing breakage.

It is also an object of the present invention to provide a plasma processing apparatus and a processing method capable of smoothly performing a dechucking process of a substrate by effectively removing an electrostatic force between the substrate and the electrostatic chuck after plasma processing of the substrate have.

According to an aspect of the present invention, there is provided a plasma processing method including: a first step of applying power to an electrostatic chuck on which a substrate is placed; a second step of supplying a cooling gas between the substrate and the electrostatic chuck; And a third step of forming a plasma inside the plasma display panel. The first step is a step of applying a voltage stepwise so that the waveform of the magnitude of the applied voltage with respect to time has a stepped shape.

Here, in the first step, it is optimal that the time for which the power source is applied and reaches the required voltage is in the range of 0.5 to 1.0 seconds.

It is also preferable that the cooling gas is supplied so as to gradually increase to the required amount in the second step.

On the other hand, when the amount of leakage current leaked through the electrostatic chuck exceeds a predetermined value in the first step, the second step or the third step so as to prevent the problem of deformation or breakage of components of the substrate or the processing apparatus It is preferable to stop the plasma treatment process.

In the second or third step, it is preferable to stop the plasma treatment process when the supply amount of the cooling gas exceeds a predetermined value.

In the third step, when the value detected by the voltage sensor provided on the power supply line for forming the plasma deviates from the error range of the preset value, it is preferable to stop the plasma processing.

Further, in the second or third step, it is preferable to stop the plasma treatment process when the supply amount of the cooling gas rapidly changes.

In this way, when the plasma processing process is interrupted, it is preferable that the plasma processing is displayed to the user so that the user can respond quickly.

On the other hand, after the completion of the plasma processing on the substrate, the electrostatic force between the substrate and the electrostatic chuck is effectively canceled, so as to smoothly perform the dechucking process of the substrate, It is desirable to ground the chuck.

The dechucking process of the substrate can be performed by reducing the DC power applied to the electrostatic chuck and simultaneously applying a power source having a pulse wave to the electrostatic chuck so as to effectively cancel the electrostatic force between the substrate and the electrostatic chuck .

The plasma processing apparatus and the plasma processing method according to the present invention improve the plasma processing condition of the substrate and prevent deformation and breakage of the substrate or each of the components by suggesting the optimal design of the factors affecting the plasma processing process There is an effect that can be done.

Hereinafter, preferred embodiments of a plasma processing apparatus and a processing method according to the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 2, the plasma processing apparatus according to the present invention includes a process chamber 10 in which a sealed space is maintained to maintain a constant pressure therein, An upper electrode 20 provided on the upper side of the inside of the process chamber 10 to which a predetermined power is applied and a base member 21 on the inner lower side of the process chamber 10 To form a predetermined electric field in the process chamber 10 by interaction with the upper electrode 20 so that a predetermined electric power is applied and the reaction gas in the process chamber 10 is converted into a plasma state. An electrode 30, an exhaust device 40 for forming a vacuum atmosphere in the process chamber 10 or discharging a reactive gas, and a plasma generator 40 for detecting the state of plasma formed in the process chamber. The upper electrode 20 and the lower electrode 30 A voltage sensor 50 installed on the connection line 51 for transmitting the electric power to the lower electrode 30 and detecting the magnitude of the applied high frequency voltage; And a DC power supply device 70 for applying a DC power to the electrostatic chuck 60. The plasma processing apparatus 10 is provided on one side wall of the process chamber 10 to perform plasma processing of the substrate S And a dechucking unit for separating the substrate S from the electrostatic chuck 60 after the completion of the plasma processing for the substrate S. The EPD (End Point Detector) do.

A side wall of the process chamber 10 is provided with a transfer passage 12 for loading and unloading the substrate S into and out of the process chamber 10 and an opening and closing device for opening and closing the transfer passage 12 13).

The reaction gas supply device supplies a reaction gas used for forming plasma to the inside of the process chamber 10 and is provided on the upper side of the process chamber 10 to diffuse the reaction gas to uniformly supply the reaction gas into the process chamber. And a member (11).

The voltage detector 50 senses the voltage value or waveform of the voltage applied to the upper electrode 20 or the lower electrode 30 and determines the formation state of the plasma in the process chamber 10 from the voltage value.

3, the electrostatic chuck 60 includes an upper insulating layer 61 (see FIG. 3) in which the upper surface of the lower electrode 30 located on the upper side of the base member 21 is coated with ceramics whose surface is an insulator, And a lower insulating layer 62 and an electrode pattern 63 formed between the upper insulating layer 61 and the lower insulating layer 62 and supplied with a predetermined power from the DC power supply device 70 And the base member 21, the lower electrode 30, the upper insulating layer 61, and the lower insulating layer 62 are firmly attached to each other by an adhesive material.

The electrode pattern 63 serves to generate an electrostatic force as the DC power is applied. The electrode pattern 63 is formed in various shapes according to the shape of the substrate S to be processed. The electrode pattern 63 is made of metal such as copper (Cu), nickel (Ni), or tungsten (W).

The upper surface of the upper insulating layer 61 is provided with a plurality of protrusions 64 arranged at predetermined intervals and the protrusions 64 are coated with ceramics which is an insulator. The substrate S is seated on the upper side of the protrusion 64 and the space A between the protrusions 64, that is, the space A between the substrate S and the upper insulating layer 61, (He) gas, and the cooling gas functions to maintain the temperature of the substrate S at an appropriate temperature.

The projections 64 are preferably formed in a shape in which the width of the projections 64 is reduced toward the substrate S so that the substrate S can be easily contacted and separated. In this embodiment, .

A cooling gas supplying device 101 is provided as a supply source of a cooling gas to the outside of the process chamber 10 and a space A between the substrate S and the upper insulating layer 61 is provided, And a unit pressure regulator 103 (UPC) and a plurality of valves 104 for controlling the supply amount of the cooling gas are provided on the supply passage 102 Respectively.

A wall 65 projecting from the upper insulating layer 61 and extending along the periphery of the upper insulating layer 61 so as to maintain the airtightness of the space A between the substrate S and the upper insulating layer 61 And the substrate S is seated to be in contact with the upper side of the wall 65. The wall 65 serves to prevent the cooling gas supplied to the space A between the substrate S and the upper insulating layer 61 from leaking.

The EPD system 80 includes a view port 81 provided through one side wall of the process chamber, a transparent window 82 provided in the view port 81, a transparent window 82 and an optical cable 83 And an optical analyzer 84 connected thereto.

When the light received by the transparent window 82 of the view port 81 is transmitted to the optical analyzer 84 through the optical cable 83, the EPD system 80 transmits the optical signal of the specific wavelength And the end point of the plasma process is determined.

The dechucking unit is provided between the electrode pattern 63 of the electrostatic chuck 60 and the DC power supply 70 so as to allow at least one of the electrode patterns 63 to be selectively connected to the DC power supply 70 or the ground And a port 90 of the control unit.

The port 90 is provided with a switch such as a relay capable of selectively releasing and maintaining the ground state and the port 90 is connected to the DC power supply device 70 in the process of chucking the substrate S onto the electrostatic chuck To the electrode pattern 63. In the process of dechucking the substrate S from the electrostatic chuck, the electrode pattern 63 is connected to the ground.

The port 90 is preferably provided to be connected to various points of the electrode pattern 63 in order to smoothly apply power from the DC power supply device 70 to the electrode pattern 63, It is preferable to smoothly move the charge toward the ground in the dechucking process to effectively remove the charge on the electrode pattern 63. [

It is preferable to further include sensing means for detecting whether the grounding is correctly performed by detecting the charged state of the electrode pattern 63 in real time.

4, the dechucking unit removes the charge on the electrode pattern 63 after the plasma treatment of the substrate S to remove the charges on the electrode pattern 63 and between the substrate S and the electrostatic chuck 60 And an AC power supply 91 connected to the electrode pattern 63 to apply an AC power to the electrode pattern 63 so that the electrostatic force of the electrode pattern 63 can be released.

The AC power supply 91 is connected to a DC power supply (not shown) for dechucking the substrate S from the electrostatic chuck 60 after the plasma processing of the substrate S in the process chamber 10 is finished And the role of applying AC power to the electrode pattern 63 while reducing the voltage applied from the electrode pattern 63 to the electrode pattern 63 or connecting the electrode pattern 63 to the ground by the operation of the port 90 .

According to another embodiment of the present invention, since the AC power applied to the electrode pattern 63 is pulse wave, a power source applied to the electrode pattern 63 for dechucking the substrate S from the electrostatic chuck 60 The charge on the electrode pattern 63 can be effectively removed as compared with the case where it is temporarily disconnected.

In the meantime, when the AC power is applied to the electrode pattern 63 as in the other embodiment of the present invention, the port 90 for selectively connecting the electrode pattern 63 to the DC power supply device 70 or the ground May not be provided. In this case, the dechucking process of the substrate S is performed by reducing the voltage applied from the DC power supply device 70 while changing the AC power of the AC power supply device 91 to the electrode pattern 63 of the electrostatic chuck 60 ).

In addition, it is preferable to further include sensing means for sensing the charged state of the electrode pattern 63 in real time so as to determine whether the charge on the electrode pattern 63 has been removed.

5, the dechucking unit includes a power supply device 92 provided separately from the DC power supply device 70, a power supply device 92, and an electrode pattern (not shown) And a signal conversion device 93 connected to the signal conversion device 93 and the signal conversion device 93, respectively.

The signal converting apparatus 93 removes the charge on the electrode pattern 63 after the plasma processing of the substrate S to remove the charges on the substrate S The power supplied from the power supply device 92 is converted into a pulse wave signal and applied to the electrode pattern 63 of the electrostatic chuck 60 so that the electrostatic force between the electrostatic chucks 60 can be released.

Here, the signal conversion device 93 is connected to a separate power supply device 92, but the present invention is not limited thereto. The signal conversion device 93 may be connected to the DC power supply device 70, Converted into a pulsed wave signal, and applied to the electrode pattern 63. [0064]

According to another embodiment of the present invention, the dechucking process of the substrate S may be performed by reducing the voltage applied from the DC power supply device 70 to the electrode pattern 63, Converting the power supplied from the power supply device 92 into a pulse wave signal through the signal conversion device 93 and applying the pulse wave signal to the electrode pattern 63 while connecting the electrode pattern 63 to the ground. Therefore, in order to dechuck the substrate S from the electrostatic chuck 60, the charge on the electrode pattern 63 can be effectively removed as compared with the case where the power source applied to the electrode pattern 63 is temporarily blocked.

In the case where the electrode pattern 63 is applied with the power converted to the pulsed wave signal as in the other embodiment of the present invention, the electrode pattern 63 may be selectively supplied to the DC power supply device 70 or the ground The port 90 may not be provided. In this case, the dechucking process of the substrate S is performed by applying a power source having a pulse wave to the electrode pattern 63 of the electrostatic chuck 60 while reducing the magnitude of the voltage applied from the DC power supply device 70 Lt; / RTI >

In addition, it is preferable to further include sensing means for sensing the charged state of the electrode pattern 63 in real time so as to determine whether the charge on the electrode pattern 63 has been removed.

Hereinafter, the plasma processing process of the plasma processing apparatus according to the present invention will be described in detail.

6, the process of the plasma processing apparatus using the electrostatic chuck 60 according to the present invention includes the steps of (1) transferring the substrate S into the process chamber 10, (S10) of placing the wafer W on the chuck 60 and forming a vacuum inside the process chamber 10, (2) applying a direct current power to the static billet 60 (S20), and (3) A step S30 of supplying a cooling gas to the space A between the substrate S and the electrostatic chuck 60 and a step S30 of applying a bias voltage to the upper electrode 20 and the lower electrode 30, (S40) of forming plasma in the chamber 10, (5) terminating the plasma process by the EPD system 80 (S50), and (6) (7) terminating the supply of the cooling gas (S70); (8) shutting off the DC power applied to the electrode pattern (63) of the electrostatic chuck (60) The substrate S is detached from the electrostatic chuck 60 Significantly to step (S80) and (9) Step (S90) for exhausting the reaction gas inside the process chamber 10 is composed of nine steps.

The first step S10 is to transfer the substrate S to the inside of the process chamber 10 through the transfer passage 12 and to place the substrate S on the electrostatic chuck 60, 40 to form a vacuum chamber inside the process chamber 10.

Step S20 of applying DC power to the electrostatic chuck 60 is performed by applying a direct current power to the electrode pattern 63 of the electrostatic chuck 60 to cause polarization phenomenon on the surfaces of the substrate S and the upper insulating layer 61 The substrate S is chucked by the electrostatic chuck 60 by the electrostatic force.

Here, the chucking force, which is the force that the substrate S is attracted to the electrostatic chuck 60, is greatly affected by the magnitude of the voltage applied to the electrode pattern 63. When the applied voltage is small, the chucking force is weak Vibration or the like may be generated on the substrate S during the plasma processing process. If the applied voltage is large, the substrate S may be damaged by a large chucking force, and the electrostatic chuck 60 may be damaged A problem arises in that the amount of leaked current increases. Therefore, an optimum design for the range of the magnitude of the applied voltage and the method of applying the voltage is required.

The adjustment of the magnitude of the voltage applied to the electrode pattern 63 of the electrostatic chuck 60 can be judged from the magnitude of the amount of current leaked through the electrostatic chuck. That is, the value of the leakage current is set in a state in which the chucking force is optimal, and the magnitude of the voltage is determined by determining the increase or decrease in the magnitude of the set value.

A step S30 of supplying a cooling gas between the substrate S and the electrostatic chuck 60 is performed in a space A between the cooling gas supplying device 101 and the substrate S and the electrostatic chuck 60, And injecting a cooling gas such as helium gas into the space A between the substrate S and the electrostatic chuck 60 through the supply passage 102 connecting the substrate S and the electrostatic chuck 60.

That is, when the temperature of the substrate S is excessively high, there is a risk that the temperature of the substrate S is excessively high because the substrate S is exposed to the plasma during the process. If the temperature of the substrate S is excessively high, There is a problem of defective, which is supplemented properly through the cooling gas.

Here, the supply amount of the cooling gas is controlled through the pressure regulator 103 provided on the supply path 102, and the cooling efficiency of the cooling gas is closely related to the chucking force of the substrate S. That is, in a state where the chucking force of the substrate S is optimal, the cooling gas flows into the space A between the substrate S and the electrostatic chuck 60 to perform the cooling action, The substrate S vibrates due to the pressure of the supplied cooling gas and the cooling gas leaks from the space A between the substrate S and the electrostatic chuck 60 so that the cooling efficiency A problem of degradation occurs. Therefore, an optimal design for the supply amount and the supply method of the cooling gas is required.

A step S40 of forming a plasma in the process chamber 10 is performed by supplying the reaction gas into the process chamber 10 in a vacuum atmosphere by the reaction gas supply device and supplying the reaction gas to the upper electrode 20 and the lower electrode A predetermined electric field is formed between the upper electrode 20 and the lower electrode 30 when a predetermined electric power is applied to the upper electrode 20 and the lower electrode 30 and the reaction gas is activated by the electric field to form a plasma.

The step S50 of terminating the plasma process by the EPD system 80 is a process in which the light received by the transparent window 82 of the view port 81 of the EPD system 80 is transmitted through the optical cable 83 to the optical analyzer 84 The optical analyzer 84 amplifies the transmitted light, detects a specific wavelength band to determine an end point of the plasma process, and terminates the plasma process.

The step of terminating the formation of the plasma within the process chamber 10 may include controlling the reaction gas supply device to shut off the supply of the reaction gas into the process chamber 10, And blocking the high-frequency voltage applied to the lower electrode 30.

The step S70 of terminating the supply of the cooling gas controls the pressure regulator 103 or the valve 104 to supply the cooling gas to the space A between the substrate S and the electrostatic chuck 60 .

The step S80 of dechucking the substrate S from the electrostatic chuck 60 by interrupting the DC power applied to the electrode pattern 63 of the electrostatic chuck 60 is performed by the electrode pattern 63 of the electrostatic chuck 60 In order to prevent problems such as deformation and breakage of the substrate S due to the sticking phenomenon caused by the charge remaining on the electrode pattern 63 when the power source applied to the electrode pattern 63 is temporarily cut off, (63) to the ground.

That is, the port 90 cuts off the power applied to the electrode pattern 63 by the operation of the switch, and at the same time connects the electrode pattern 63 to the ground, whereby the charges on the electrode pattern 63 It is moved to the ground and removed. When the sensing means senses the charged state of the electrode pattern 63 and the grounding is completed correctly, the substrate S is dechucked from the electrostatic chuck.

The process of dechucking the substrate S from the electrostatic chuck S80 may be performed while reducing the magnitude of the voltage applied from the power supply device 70 to the electrode pattern 63 after the completion of the plasma process, Or by applying a power source having a pulse wave.

The process of discharging the reaction gas inside the process chamber 10 (S90) comprises a process of controlling the exhaust device 40 to remove the reaction gas inside the process chamber 10. [

Hereinafter, the present invention proposes an optimal design that can prevent breakage of the substrate S and parts of the processing apparatus, and can smoothly perform the plasma processing process.

First, the continuation condition of the plasma processing process is set as follows.

(1) The amount of leakage current should be less than a predetermined value (1 mA) in step (S20) of applying DC power to the electrostatic chuck 60. (2) In step (S30) The supply amount of the cooling gas controlled by the pressure regulator 103 is not more than the set value (1 mA) and the supply amount of the cooling gas controlled by the pressure regulator 103 is supplied at the predetermined amount (10 sccm), (3) The supply amount of the cooling gas controlled by the pressure regulator 103 is equal to or less than the set value (1 mA) and supplied from the predetermined amount (10 sccm), and the voltage value detected by the voltage sensor 50 Three conditions that the formation state of the plasma is good are set, and in the case where such conditions are not satisfied in the plasma processing process, the problems caused by stopping the plasma processing step at each step are prevented in advance.

7, in step S20 of applying DC power to the electrostatic chuck 10, the leakage current is set to a value equal to or less than a predetermined value (1 mA), preferably about 70% It is preferable that the processing step is performed as it is, and when the leakage current amount exceeds the predetermined value, preferably exceeds the predetermined value of about 70%, the processing step is stopped and the substrate S or the processing Thereby preventing problems such as deformation or breakage of parts of the apparatus (S21).

8, in relation to the method of applying power to the electrostatic chuck 10, the DC power is stepped up so that the waveform of the magnitude of the voltage with respect to the time of the applied DC power becomes a stepped shape (A), (b) when the voltage is gradually increased so that the waveform forms a slope, and (c) when the required voltage is applied at a time so that the waveform has a vertical straight line, (B) shows a case where the DC power source is applied stepwise with respect to (c) when the DC power source is applied to the substrate S or the plasma processing apparatus It is possible to achieve the object of the present invention which can prevent the breakage and smoothly perform the etching process.

In this case, the case (a) in which DC power was stepwise applied was optimal, and the time from the first voltage to the required voltage was most preferably from 0.5 second to 1.0 second.

On the other hand, if the amount of leakage current exceeds the preset value and the plasma processing process is interrupted in step S20 of applying DC power to the electrostatic chuck 10, step S22 is further provided . Therefore, when the plasma process is interrupted due to the excess of the leakage current, the user can recognize the plasma process quickly and respond appropriately.

As shown in Fig. 9, in the step S30 of supplying the cooling gas, when the amount of leakage current is equal to or less than a predetermined value (1 mA), preferably about 70% of the preset value, If the amount of leakage current exceeds a predetermined value, and preferably exceeds a predetermined level of about 70%, the processing process is stopped to change or break the components of the substrate S or the processing apparatus (S31).

In addition, in the step S30 of supplying the cooling gas, even when the leakage current amount is equal to or less than a predetermined value, the supply amount of the cooling gas controlled by the pressure regulator 103 deviates from the error range of the predetermined amount (10 sccm) The process is stopped (S32).

When the waveform of the supply amount of the cooling gas sensed by the pressure regulator 103 changes abruptly when the leakage current amount is equal to or less than a predetermined value in the step S30 of supplying the cooling gas, In this case, too, the plasma treatment process is interrupted to prevent problems such as breakage of the plasma treatment device (S32).

10, when the supply amount of the cooling gas to be controlled by the pressure regulator 103 is temporarily supplied (e), the chucking force of the substrate (S) S is oscillated, it is preferable to control the pressure regulator 103 so that the supply amount of the cooling gas gradually increases to the required amount (d).

On the other hand, in the step S30 of supplying the cooling gas, if the amount of leakage current exceeds a predetermined value, or the supply amount of the cooling gas deviates from an error range of a predetermined value, or the supply amount of the cooling gas rapidly changes, If it is interrupted, it is preferable to further include a step (S33) of displaying this to the user. Therefore, when the plasma processing process is interrupted, the user can quickly recognize this and can respond appropriately.

As shown in FIG. 11, in the plasma forming step S40, the process is performed as it is at the level of the leakage current of not more than a predetermined value (1 mA), preferably about 70% When the amount of leakage current exceeds a predetermined value, and preferably exceeds a predetermined level of about 70%, the processing process is interrupted so that the problem of deformation or breakage of the substrate S or parts of the processing apparatus (S41).

When the supply amount of the cooling gas controlled by the pressure regulator 103 deviates from the error range of the predetermined amount (10 sccm) even in the case where the leakage current amount is equal to or less than the preset value in the plasma forming step S40, The process is interrupted to prevent problems such as breakage of the plasma processing apparatus (S42).

When the waveform of the supply amount of the cooling gas sensed by the pressure regulator 103 is abruptly changed in the plasma forming step S40 when the amount of leakage current is less than a predetermined value, this means leakage of the cooling gas In this case, too, the plasma treatment process is interrupted to prevent problems such as breakage of the plasma treatment apparatus (S42).

Further, even if the leakage current amount is equal to or less than a predetermined value in the plasma forming step S40, if the formed state of the plasma judged from the voltage value VDC of the DC power source sensed by the voltage sensor 50 is not good That is, when the voltage value sensed by the voltage detector 50 deviates from an error range of a predetermined value, the plasma processing process is interrupted to prevent the problem of breakage of the plasma processing apparatus (S43).

On the other hand, in the plasma forming step (S40), when the leakage current amount exceeds a predetermined value, the supply amount of the cooling gas deviates from an error range of a predetermined value, the supply amount of the cooling gas rapidly changes, If the plasma processing process is interrupted, it is preferable that the step (S44) is further provided to the user. Therefore, when the plasma processing process is interrupted, the user can quickly recognize this and can respond appropriately.

Each of the conditions for performing the plasma treatment process described above may be applied to the plasma treatment process individually or a combination thereof, and all the conditions may be applied together.

As described above, the plasma processing apparatus and the processing method according to the present invention provide optimal design for the voltage application method and the cooling gas supply method applied to the electrostatic chuck 60, And it is possible to prevent breakage of the substrate S or parts of the processing apparatus.

Further, the plasma processing apparatus and the processing method according to the present invention may further include a step of performing a plasma processing process according to the amount of leakage current from the electrostatic chuck 60 during the plasma processing process, the supply amount of the cooling gas, It is possible to prevent breakage of the parts and smoothly perform the plasma processing process.

The plasma processing apparatus according to the present invention can completely remove the electrostatic force between the substrate S and the electrostatic chuck 60 by removing the charges on the electrode pattern through the dechucking unit after the plasma processing of the substrate S Therefore, there is an effect that the dechucking process of the substrate S can be performed smoothly while preventing the electrostatic chuck 60 from causing an error in electrostatic force, a sticking phenomenon, and deformation or breakage of the substrate S.

1 is a partial sectional view showing a conventional electrostatic chuck.

2 is a longitudinal sectional view showing a plasma processing apparatus according to the present invention.

3 is an enlarged partial sectional view of an electrostatic chuck of a plasma processing apparatus according to the present invention.

4 is a schematic view showing another embodiment of the electrostatic chuck and dechucking unit of the plasma processing apparatus according to the present invention.

5 is a schematic view showing still another embodiment of the electrostatic chuck and dechucking unit of the plasma processing apparatus according to the present invention.

6 is a flowchart showing a plasma processing process of the plasma processing apparatus according to the present invention.

7 is a flowchart showing a processing process corresponding to the amount of leakage current in the step of applying DC power to the electrostatic chuck of the plasma processing apparatus according to the present invention.

8 is a graph showing a comparison of a method of applying DC power to the electrostatic chuck in the plasma processing apparatus according to the present invention.

FIG. 9 is a flowchart showing a processing process corresponding to the amount of leakage current and the supply amount of cooling gas in the step of supplying cooling gas in the plasma processing apparatus according to the present invention.

10 is a graph showing a comparison of the method of supplying the cooling gas in the plasma processing apparatus according to the present invention.

FIG. 11 is a flowchart showing the process steps corresponding to the amount of leakage current, the supply amount of cooling gas, and the plasma forming state in the step of forming plasma in the plasma processing apparatus according to the present invention.

DESCRIPTION OF THE REFERENCE SYMBOLS

S: substrate 10: process chamber

11: diffusion member 12:

13: opening and closing device 20: upper electrode

21: base member 30: lower electrode

40: Exhaust device 50: Voltage detector

51: connection line 60: electrostatic chuck

61: upper insulator 62: lower insulator

63: electrode pattern 64: projection

65: wall 70: DC power supply

80: EPD system 81: view port

82: transparent window 83: optical cable

84: Optical analyzer 90: Port

91: AC power supply 92: Power supply

93: Signal conversion device 101: Cooling gas supply device

102: supply passage 103: pressure regulator

104: Valve

Claims (28)

A first step of applying power to an electrostatic chuck on which a substrate is placed so that a waveform having a magnitude of an applied voltage with respect to time has a stepped shape; A second step of supplying a cooling gas between the substrate and the electrostatic chuck; A third step of forming a plasma inside the process chamber; And And stopping the plasma processing step when the supply amount of the cooling gas is abruptly changed in the second step or the third step. The method according to claim 1, And the second step comprises supplying the cooling gas so as to gradually increase to a required amount. 3. The method of claim 2, Further comprising the step of stopping the plasma processing step when the amount of leakage current leaked through the electrostatic chuck exceeds a predetermined value in the first step, the second step or the third step. The method of claim 3, Further comprising the step of stopping the plasma processing step when the supply amount of the cooling gas exceeds a predetermined value in the second step or the third step. 5. The method of claim 4, And stopping the plasma processing step when the value detected by the voltage detector provided on the power supply line for forming the plasma deviates from an error range of a predetermined value in the third step . delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete 6. The method according to any one of claims 1 to 5, Further comprising the step of cutting off the DC power applied to the electrostatic chuck and grounding the electrostatic chuck after the completion of the plasma treatment on the substrate. 6. The method according to any one of claims 1 to 5, Further comprising the step of reducing the DC power applied to the electrostatic chuck after the completion of the plasma treatment on the substrate and applying a power source having a pulse wave to the electrostatic chuck. 6. The method according to any one of claims 1 to 5, Further comprising the step of indicating if the plasma processing process is interrupted. The method according to claim 1, Wherein in the first step, a time for which power is applied to a required voltage is in a range of 0.5 to 1.0 seconds.

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