KR20170073055A - Electrostatic chuck - Google Patents

Abstract

The present invention relates to an electrostatic chuck, and more particularly, to an electrostatic chuck for fixing a substrate with an electrostatic attraction force in a process chamber for manufacturing a flat panel display.
The present invention is characterized in that first and second positive electrode power supply terminals and first and second negative electrode power supply terminals are respectively provided at both ends of first and second chuck electrodes for generating an electrostatic force of the electrostatic chuck, A direct current voltage between the positive and negative electrodes is applied to the first negative electrode power supply terminal and the second positive electrode power supply terminal respectively located at both ends of the first chuck electrode and the first positive electrode power supply terminal and the second positive electrode power supply terminal, The positive and negative dc voltages are respectively applied to the power terminal and the second negative electrode power terminal to generate heat in the first and second chuck electrodes to thereby prevent the moisture from being adsorbed and absorbed by the electrostatic chuck At the same time, the moisture adsorbed and absorbed by the electrostatic chuck are removed.

Description

Electrostatic chuck}

The present invention relates to an electrostatic chuck, and more particularly, to an electrostatic chuck for fixing a substrate with an electrostatic attraction force in a process chamber for manufacturing a flat panel display.

2. Description of the Related Art [0002] In recent years, as the society has become a full-fledged information age, a display field for processing and displaying a large amount of information has rapidly developed, and a variety of flat display devices have been developed Be in the spotlight.

Specific examples of the flat panel display device include a liquid crystal display device (LCD), a plasma display panel (PDP), a field emission display (FED) Electroluminescence Display Device (ELD), and Organic Light Emitting Diode (OLED). These flat panel display devices have excellent performance in reducing thickness, weight, and power consumption. ).

Such a flat panel display device includes a thin film deposition process for forming a thin film of a predetermined material on a substrate surface, a photo-lithography process for exposing a selected portion of the thin film, a process for removing the exposed portion of the thin film, The dry etching process including the dual thin film deposition process and the like are carried out in a normally closed process chamber and the process chambers of the respective process chambers A chuck for fixing the substrate is provided.

Here, the chuck can be classified into mechanical type, vacuum type, and electrostatic type according to the substrate fixing principle. However, by using the absorption principle by the electrostatic force, the chuck can minimize the physical contact with the substrate, Electrostatic chuck (ESC) is in the spotlight.

When the substrate moves to another process after a plurality of processes are performed in a closed process chamber after the substrate is mounted on the electrostatic chuck, the electrostatic chuck is extracted to the outside of the process chamber, So as to be fixed.

During the movement of the electrostatic chuck outside the process chamber, the electrostatic chuck is exposed to the atmosphere. In the process of being exposed to the atmosphere, the electrostatic chuck sucks and absorbs moisture in the air.

The moisture adsorbed and absorbed by the electrostatic chuck causes a short of the power supply line of the electrostatic chuck or shortens the life of the electrostatic chuck itself.

SUMMARY OF THE INVENTION The present invention has as its first object to remove water adsorbed and absorbed by an electrostatic chuck without any additional apparatus or process.

The second object is to improve the efficiency of the process.

In order to achieve the above object, according to the present invention, there is provided an electrostatic chuck wherein a substrate is seated and fixed in a substrate processing apparatus, comprising: a chuck base; A chuck body fixed above the chuck base, on which the substrate is seated and fixed; A first chuck electrode provided in the chuck body and having first and second cathode power terminals at both ends; And a second chuck electrode disposed within the chuck body and spaced apart from the first chuck electrode and having a first cathode power terminal and a second cathode power terminal at both ends, The first and second chuck electrodes and the first and second chuck electrodes are electrically connected to each other, and when a voltage is applied to the first cathode power terminal, an electrostatic force is generated between the first and second chuck electrodes, The first and second chuck electrodes provide an electrostatic chuck that generates heat when voltage is applied to both the first negative electrode power supply terminal and the second positive electrode power supply terminal at the same time.

As described above, according to the present invention, the electrostatic chuck is provided with first and second positive electrode power supply terminals and first and second negative electrode power supply terminals respectively at both ends of first and second chuck electrodes for generating an electrostatic force In a situation in which the substrate is not required to be chucked, the direct-current voltages of the positive and negative electrodes are respectively applied to the first negative electrode power supply terminal and the second positive electrode power supply terminal respectively located at both ends of the first chuck electrode, The first and second chuck electrodes generate a heat by applying a DC voltage between the positive and negative electrodes to the first positive power supply terminal and the second negative power supply terminal, respectively.

As a result, there is an effect of preventing moisture from being adsorbed and absorbed by the electrostatic chuck, and at the same time, there is an effect of removing moisture adsorbed and absorbed by the electrostatic chuck.

Therefore, there is an effect that it is possible to prevent a short circuit of the power supply line of the electrostatic chuck by the moisture adsorbed or absorbed by the electrostatic chuck, or a problem that the lifetime of the electrostatic chuck itself is shortened. Further, It is possible to shorten the processing time and improve the efficiency of the process.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view schematically showing the inside of a substrate processing apparatus provided with an electrostatic chuck according to an embodiment of the present invention; FIG.
Figure 2a is a detailed cross-sectional view of the electrostatic chuck of Figure 1;
FIG. 2B is a plan view schematically showing the arrangement of the first and second chuck electrodes of the electrostatic chuck of FIG. 1; FIG.
3 is a plan view schematically showing the inside of a clean room for manufacturing a flat display device.
4A to 4B are cross-sectional views schematically showing a driving principle of an electrostatic chuck according to an embodiment of the present invention.

The present invention provides an electrostatic chuck wherein a substrate is seated and fixed in a substrate processing apparatus, the electrostatic chuck having a chuck body on which the substrate is seated and fixed and a chuck body provided on both sides of the chuck body, And a second chuck electrode disposed inside the chuck body and spaced apart from the first chuck electrode and having a first cathode power terminal and a second cathode power terminal at both ends of the first chuck electrode, An electrostatic force is generated between the first and second chuck electrodes when a voltage is applied between the first positive electrode power supply terminal and the first negative electrode power supply terminal, And the first and second chuck electrodes provide an electrostatic chuck that generates heat when voltage is applied to both the first negative electrode power supply terminal and the second positive electrode power supply terminal at the same time.

In this case, the substrate is fixed to the surface of the chuck body by the electrostatic force. When a voltage is applied to the first anode power terminal of the first chuck electrode, a chucking force of the anode is generated, When a voltage is applied to the first negative electrode power terminal, a chucking force of the negative electrode is generated, and the electrostatic force is generated by the chucking force of the positive electrode and the negative electrode.

The first and second chuck electrodes are sandwiched between the first and second insulating layers. The first and second chuck electrodes are connected to the chuck body And has a spiral structure from the edge of the chuck body toward the center along the shape of the chuck body.

The first and second chuck electrodes may be formed of one selected from the group consisting of a bar type, a ring type, and a disk type, And the second cathode power terminal and the second cathode power terminal are spaced apart from each other.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view schematically showing the inside of a substrate processing apparatus provided with an electrostatic chuck according to an embodiment of the present invention. FIG. 2 (a) is a detailed sectional view of the electrostatic chuck of FIG. 1, And a plan view schematically showing the arrangement of the second chuck electrodes.

1, the substrate processing apparatus 100 includes a chamber 110 provided with a space in which a substrate 1 is processed, a substrate holder 110 provided below the chamber 110, Unit 120 and a gas injection unit 130 provided at an upper portion of the substrate positioning unit 120 to inject a process gas for depositing or etching a thin film.

At this time, the substrate placing unit 20 is made of an electrostatic chuck which chucks or dechucks the substrate 1 using an electrostatic force.

The substrate 1 is chucked to a substrate holding unit 120 (hereinafter referred to as an electrostatic chuck) 120 inside the chamber 110 to process the substrate 1 in the substrate processing apparatus 100, ), And then the process of dechucking for the next step is repeated several times.

Here, the electrostatic chuck 120 is a substrate support for fixing the substrate 1 by using an electrostatic force. As shown in FIG. 2A, the electrostatic chuck 120 includes a chuck base 121 serving as a supporting frame erected from the bottom of the chamber 110, And a chuck body 123 which is fixed to the upper portion and directly supports the substrate 1 and exerts an attractive force by static electricity.

The double chuck base 121 may be made of aluminum (Al) or an aluminum alloy. In particular, when the advancing process in the chamber 110 is a thin film deposition using a plasma or a dry etching, 1) can serve also as another electrode which electrically acts on the plasma electrode disposed on the upper surface. In this case, an RF voltage is applied to the plasma electrode and a bias voltage is applied to the chuck base 121.

On the upper surface of the chuck base 121, a chuck body 123 is adhered and fixed.

The chuck body 123 may be made of ceramic. For example, the chuck body 123 may be made of alumina (Al2O3), yttrium oxide (Y2O3), aluminum nitride, or the like. The chuck body 123 may be anodizing, sintering, or the like.

The chuck body 123 is a part where an electrostatic attraction force is exerted to fix the substrate 1 while simultaneously fixing the substrate 1 and includes a first insulating layer 125a and an electrode part 200 located on the first insulating layer 125a, And a second insulating layer 125b that covers the electrode unit 200 and on which the substrate 1 is mounted.

Here, the electrode unit 200 includes first and second chuck electrodes 210 and 220 having two different polarities, and the first and second chuck electrodes 210 and 220 are alternately arranged .

That is, the DC voltage of the anode is applied to the first chuck electrode 210, so that the first chuck electrode 210 generates the chucking force of the anode, and the DC voltage of the cathode is applied to the second chuck electrode 220 So that the second chuck electrode 220 generates a chucking force of the negative electrode.

Accordingly, an electrostatic force is generated between the first and second chuck electrodes 210 and 220 due to the positive and negative chucking forces.

The electrode unit 200 may be made of a conductive metal, and preferably made of tungsten (W) having a low specific resistance.

2B, the first and second chuck electrodes 210 and 220 of the electrode unit 200 are spaced apart from each other by a predetermined distance. The chuck body 123 Like the shell of the shell from the edge of the shell to the center of the shell.

The electrode unit 200 may have various shapes. For example, the electrode unit 200 may be formed in various shapes such as a bar type, a ring type, a disk type, and the like.

Here, the chucking and dechucking of the electrostatic chuck 120 will be described in more detail. After the substrate 1 is loaded into the chamber 110, the first and second chuck electrodes The electrostatic force generated by the positive and negative chucking forces of the first and second chuck electrodes 210 and 220 is generated on the surface of the electrostatic chuck 120 so that the substrate 1 is firmly fixed.

In this state, when the process is completed in the chamber 110, the DC voltage of the positive and negative electrodes supplied to the first and second chuck electrodes 210 and 220 is cut off, and the substrate 1 is transferred to the electrostatic chuck 120 ) In order to perform the dechucking operation.

A first positive power supply terminal 211 and a first negative power supply terminal 221 are provided at one end of each of the first and second chuck electrodes 210 and 220 to apply a DC voltage to the positive and negative electrodes, The electrostatic chuck 120 according to the embodiment of the present invention includes the second negative electrode power supply terminal 213 and the second positive electrode power supply terminal 223 as the other ends of the first and second chuck electrodes 210 and 220.

That is, the first chuck electrode 210 has a first anode power supply terminal 211 at one end and a second cathode power supply terminal 213 at the other end thereof. A power source terminal 221 and a second positive electrode power source terminal 223 at the other end.

Accordingly, the electrostatic chuck 120 according to the embodiment of the present invention can prevent the electrostatic force due to the positive and negative chucking forces generated by the DC voltages of the positive and negative electrodes applied to the first and second chuck electrodes 210 and 220 When the substrate 1 is not chucked, heat is dissipated through DC voltages of the positive and negative electrodes supplied to both ends of the first and second chuck electrodes 210 and 220 .

In order to chuck the substrate 1 through the electrostatic chuck 120, the first positive electrode power supply terminal 211 and the second positive electrode power supply terminal 211 provided at one ends of the first and second chuck electrodes 210 and 220, respectively, A direct current voltage between the anode and the cathode is applied to the cathode power supply terminal 221 to generate a chucking force of the anode on the first chuck electrode 210 and a chucking force of the cathode on the second chuck electrode 220 .

An electrostatic force is generated between the first and second chuck electrodes 210 and 220 by the chucking forces of the positive and negative electrodes so that the electrostatic chuck 120 chucks the substrate 1. [

When the electrostatic chuck 120 is not required to chuck the substrate 1, the first positive electrode power supply terminal 211 and the second negative electrode power supply terminal 213, which are located at both ends of the first chuck electrode 210, A direct current voltage of positive polarity and a negative polarity is applied to the first chuck electrode 220 and the first negative power supply terminal 221 and the second positive power supply terminal 223 located at both ends of the second chuck electrode 220, Voltage is applied.

As a result, heat is generated in the first and second chuck electrodes 210 and 220, and moisture adsorbed and absorbed by the electrostatic chuck 120 is removed.

Therefore, it is possible to prevent a short circuit of the power supply line of the electrostatic chuck 120 by the moisture adsorbed or absorbed by the electrostatic chuck 120 or shorten the lifetime of the electrostatic chuck 120 itself . This will be described in more detail with reference to FIG. 3 and FIG.

FIG. 3 is a plan view schematically showing the inside of a clean room for manufacturing a flat display device, and FIGS. 4a to 4b are cross-sectional views schematically showing the driving principle of the electrostatic chuck according to the embodiment of the present invention.

Here, various manufacturing processes of the flat panel display device are performed in a clean room 300, which is an environmentally controlled closed space, in which various factors such as temperature, humidity, illuminance, air flow, air pressure, 300 are respectively provided with pan filters to control the internal temperature and humidity as well as to circulate the air in the clean room 300 and to maintain a high degree of cleanliness.

As shown in FIG. 3, in the clean room 300, a plurality of process chambers 310 performing the same or related functions are arranged in a group.

The inside of the clean room 300 can be divided into a vacuum chamber 320 where the various process chambers 310 are located and a standby portion 330. In the vacuum chamber 320, The substrate 1 is chucked by the electrostatic chuck 120 in the process chambers 310.

When the processed substrate 1 is moved to another clean room to proceed to another process, the electrostatic chuck 120 is moved from the standby portion 330 inside the clean room 100 to the starting point of the A line along the B line .

At this time, moisture or the like in the air is adsorbed and absorbed by the electrostatic chuck 120 moving through the air gap 330 inside the clean room 100. In this way, when the electrostatic chuck 120 absorbs moisture and absorbs moisture The short circuit of the power supply line of the electrostatic chuck 120 or the lifetime of the electrostatic chuck 120 itself is shortened.

Therefore, the electrostatic chuck 120 according to the embodiment of the present invention is not required to have a separate process for removing the moisture adsorbed and hygroscopic on the electrostatic chuck 120. The electrostatic chuck 120 according to the embodiment of the present invention includes the chuck body 123 for generating the electrostatic force The electrostatic chuck 120 moves along the line B at the standby portion 330 by applying the direct voltage of the positive electrode and the negative electrode to both ends of the first and second chuck electrodes 210 and 220, Heat is generated from the two-electrode electrodes 210 and 220 so that the moisture absorbed and adsorbed by the electrostatic chuck 120 is removed.

4A, when the electrostatic chuck 120 is moved along the line A in the vacuum 320 inside the clean room 300, DC voltages of positive and negative electrodes are applied to the first negative power supply terminal 211 and the first negative power supply terminal 221 provided at one end of the second chuck electrode 220, respectively.

Therefore, the electrostatic chuck 120 is held in the chucking state of the substrate 1 through the electrostatic force generated by the chucking force of the anode of the first chuck electrode 210 and the chucking force of the cathode of the second chuck electrode 220, And moves along the line A at the vacuum 320 inside the clean room 300.

When the substrate 1 is chucked on the electrostatic chuck 120, the DC voltage of the positive and negative electrodes supplied to the first and second chuck electrodes 210 and 220 is cut off, Is detached from the electrostatic chuck 120, and then the substrate 1 is moved into another clean room.

At this time, the electrostatic chuck 120 moves to the starting point of the A line along the line B at the waiting portion 330 inside the clean room 300. At this time, as shown in FIG. 4B, The voltage of the anode is applied to the first anode power supply terminal 211 provided at one end of the first electrode 210 and the second cathode power supply terminal 213 provided at the other end of the first chuck electrode 210 applies a voltage The voltage is applied.

The voltage of the negative electrode is applied to the first negative electrode power supply terminal 221 provided at one end of the second chuck electrode 220 and the voltage of the second positive electrode power supply terminal 223 The voltage of the anode is applied.

As a result, heat is generated from the first and second chuck electrodes 210 and 220 and the electrostatic chuck 120 is moved along the line B at the standby portion 330 inside the clean room 300. [ It is possible to prevent moisture in the air from being adsorbed and absorbed by the electrostatic chuck 120 due to the heat generated from the first and second chuck electrodes 210 and 220 and also to prevent the moisture adsorbed and absorbed by the electrostatic chuck 120 .

As a result, the moisture absorbed and adsorbed by the electrostatic chuck 120 can be removed, shorting of the power supply line of the electrostatic chuck 120 is caused by the moisture adsorbed or absorbed by the electrostatic chuck 120, It is possible to prevent the problem that the life of the electrostatic chuck 120 itself is shortened.

In addition, since the electrostatic chuck 120 does not require a separate process for removing moisture absorbed and adsorbed, the process time can be shortened and the efficiency of the process can be improved.

As described above, the electrostatic chuck 120 according to the embodiment of the present invention includes the first and second positive electrode power supply terminals 211 and 211 at both ends of the first and second chuck electrodes 210 and 220 for generating electrostatic force, 223 and first and second negative electrode power supply terminals 221 and 213 are respectively provided for each of the first and second chuck electrodes 210 and 220. When chucking the substrate 1, The substrate 1 is chucked by applying a DC voltage of positive polarity and negative polarity to the first negative electrode power supply terminal 211 and the first negative electrode power supply terminal 221. When the substrate 1 is not chucked, A direct current voltage of positive polarity and a negative polarity is respectively applied to the first positive power supply terminal 211 and the second negative power supply terminal 213 located at both ends of the first chuck electrode 220, The positive and negative DC voltages are respectively applied to the negative power supply terminal 221 and the second positive power supply terminal 223 so that the first and second chuck electrodes 210 and 220 Such that heat is generated.

This prevents water from being adsorbed and absorbed by the electrostatic chuck 120 and removes moisture adsorbed and absorbed by the electrostatic chuck 120.

Therefore, it is possible to prevent a short circuit of the power supply line of the electrostatic chuck 120 by the moisture adsorbed or absorbed by the electrostatic chuck 120 or shorten the lifetime of the electrostatic chuck 120 itself In addition, since the electrostatic chuck 120 does not require a separate process for removing the moisture absorbed and adsorbed, the process time can be shortened and the efficiency of the process can be improved.

The present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention.

215: Chuck body
210 and 220: first and second chuck electrodes
211: First anode power terminal
213: Second negative electrode power terminal
221: First negative electrode power supply terminal
223: Second anode power terminal

Claims (7)

An electrostatic chuck wherein a substrate is seated and fixed in a substrate processing apparatus,
A chuck body on which the substrate is seated and fixed;
A first chuck electrode provided in the chuck body and having first and second cathode power terminals at both ends;
A second chuck electrode provided in the chuck body and spaced apart from the first chuck electrode and having first and second cathode power terminals at both ends,
/ RTI >
When a voltage is applied to the first positive electrode power supply terminal and the first negative electrode power supply terminal, an electrostatic force is generated between the first and second chuck electrodes,
When a voltage is simultaneously applied to the first positive electrode power supply terminal and the second negative electrode power supply terminal and the voltage is simultaneously applied to the first negative electrode power supply terminal and the second positive electrode power supply terminal, Electrostatic chuck.
The method according to claim 1,
And the substrate is fixed to the surface of the chuck body by the electrostatic force.
The method according to claim 1,
A chucking force of an anode is generated when a voltage is applied to the first cathode power terminal of the first chuck electrode and a chucking force of the cathode is generated when a voltage is applied to the first cathode power terminal of the second chuck electrode, Wherein the electrostatic force is generated by a chucking force of the positive electrode and the negative electrode.
The method according to claim 1,
Wherein the chuck body includes first and second insulating layers, and the first and second chuck electrodes are interposed between the first and second insulating layers.
The method according to claim 1,
Wherein the first and second chuck electrodes have a spiral structure from the edge of the chuck body toward the center along the shape of the chuck body.
The method according to claim 1,
Wherein the first and second chuck electrodes are formed of one selected from a bar type, a ring type, and a disk type.
The method according to claim 1,
Wherein the first anode power terminal and the first anode power terminal are spaced apart from each other and the second cathode power terminal and the second anode power terminal are spaced apart from each other.

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