WO2011152620A2 - Electrostatic chuck and a substrate-processing device comprising the same - Google Patents

Abstract

An electrostatic chuck comprises an electrostatic layer and a heat-emitting layer. The electrostatic layer has disposed therein an electrostatic electrode which generates an electrostatic force for securing a substrate placed thereon, while also having a first heat transfer coefficient. The heat-emitting layer is disposed underneath the electrostatic layer and has disposed therein a heat-emitting electrode for heating the substrate, while also having a second heat transfer coefficient higher than the first heat transfer coefficient.

Description

Electrostatic chuck and substrate processing apparatus including the same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic chuck and a substrate processing apparatus including the same, including an electrostatic chuck for fixing a substrate, such as a wafer or a glass plate, used for manufacturing an integrated circuit device, using electrostatic power, and the same. An apparatus for processing a substrate.

In general, integrated circuit devices are manufactured by performing a deposition process, an etching process, a photolithography process, an ion implantation process, and the like on a substrate such as a wafer or a glass plate, and examples thereof include semiconductor devices or display devices. Can be.

Among the processes, the etching process may include a process chamber providing a space for performing the gas, a gas providing unit connected to the process chamber from the outside to provide a process gas corresponding to the etching process to the inside of the process chamber, and The process is performed by a substrate processing apparatus including an electrostatic chuck which is disposed inside the process chamber and supports the substrate and is fixed using electrostatic power.

Here, the electrostatic chuck includes an electrostatic layer on which the substrate is placed while an electrostatic electrode generating electrostatic power is disposed, and a heat generating layer on which a heating electrode for heating the substrate is disposed below the electrostatic layer.

Here, the heat generating electrode is uniformly disposed in the form of spirals or irregularities when viewed in a plan view, and has a high electrical conductivity and a high thermal conductivity for heat generation.

Thus, the heat generating layer has high electrical resistance because the role of insulating the heat generating electrode between the heat generating electrodes is very important.

However, since the heating layer has low thermal conductivity along with high electrical resistance for the insulating role, heat from the heating electrode may not be smoothly transferred to the interface of the substrate, and thus the substrate may not be uniformly heated. have.

An object of the present invention is to provide an electrostatic chuck capable of uniformly heating the substrate while supporting and fixing the substrate using electrostatic force.

Another object of the present invention is to provide a substrate processing apparatus including the electrostatic chuck described above.

In order to achieve the above object of the present invention, an electrostatic chuck according to one aspect includes an electrostatic layer and a heat generating layer.

The electrostatic layer has a first heat transfer coefficient while the electrostatic electrode generating the electrostatic force is disposed to fix the substrate placed thereon. The heat generating layer is disposed below the electrostatic layer, and has a second heat transfer coefficient higher than the first heat transfer coefficient while a heat generating electrode for heating the substrate is disposed.

Here, the heat generating layer may be made of a ceramic material including magnesia (MgO), yttria (Y ₂ O ₃ ) alone or a mixture thereof in aluminum nitride (AlN). In addition, the second heat transfer coefficient may be 150 to 250 W / (m · K).

In addition, the heating layer may have the same thickness as the heating electrode and have a structure surrounding the side surface of the heating electrode. In addition, the electrostatic layer may have a thickness of 1 to 5mm.

The electrostatic chuck may further include a heat insulation layer disposed below the heat generating layer and having a third heat transfer coefficient lower than the first heat transfer coefficient. Thus, the heat insulation layer may have a thickness of 0.05 to 0.5mm.

In addition, the upper surface of the heating layer may be disposed in contact with the lower surface of the electrostatic layer, the lower surface of the heating layer may be disposed in contact with the upper surface of the heat insulating layer.

In order to achieve the above object of the present invention, a substrate processing apparatus according to one aspect includes a process chamber, a gas providing unit and an electrostatic chuck.

The process chamber provides space for processing a substrate. The gas providing unit is connected to the process chamber and provides a process gas for processing the substrate into the process chamber. The electrostatic chuck is disposed inside the process chamber and is fixed while supporting a substrate to be processed through the process gas.

Accordingly, the electrostatic chuck has an electrostatic layer having a first heat transfer coefficient and an electrostatic layer having a first heat transfer coefficient while the electrostatic chuck is placed on top of the substrate and generates an electrostatic force for fixing the substrate, and heats the substrate. The heat generating electrode may include a heat generating layer having a second heat transfer coefficient higher than the first heat transfer coefficient.

Thus, the heating layer may have the same thickness as the heating electrode and may have a structure surrounding the side surface of the heating electrode.

The upper surface of the heat generating layer may be disposed in contact with the lower surface of the electrostatic layer, and the lower surface of the heat generating layer may be disposed in contact with the upper surface of the heat insulating layer.

According to such an electrostatic chuck and a substrate processing apparatus including the same, heat generation for heating the substrate under the electrostatic layer having the first heat transfer coefficient while the electrostatic electrode generating the electrostatic force is disposed to fix the substrate placed thereon. By configuring the heat generating layer on which the electrode is disposed to have a second heat transfer coefficient higher than the first heat transfer coefficient, the heat generated from the heat generating electrode is preferentially uniformly spread in the heat generating layer, and then the relatively low first heat transfer coefficient By being provided to the substrate through the electrostatic layer having a, it is possible to uniformly heat the substrate.

Therefore, the quality of integrated circuit devices such as semiconductor devices or display devices manufactured by treating the substrate through a process gas can be improved.

1 is a configuration diagram schematically showing an electrostatic chuck according to an embodiment of the present invention.

2 is a view illustrating in detail the electrostatic layer, the heating layer and the heat insulating layer in the electrostatic chuck of FIG.

3 is a configuration diagram schematically illustrating a substrate processing apparatus according to an embodiment of the present invention.

Hereinafter, an electrostatic chuck and a substrate processing apparatus including the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing the drawings, similar reference numerals are used for similar elements. In the accompanying drawings, the dimensions of the structures are shown in an enlarged scale than actual for clarity of the invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described on the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, parts, or combinations thereof.

On the other hand, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

1 is a configuration diagram schematically showing an electrostatic chuck according to an embodiment of the present invention, Figure 2 is a view showing in detail the electrostatic layer, the heating layer and the heat insulating layer in the electrostatic chuck of FIG.

1 and 2, an electrostatic chuck 100 according to an embodiment of the present invention includes an electrostatic layer 200, a heat generating layer 300, a heat insulating layer 400, and a support body 500.

The electrostatic layer 200 supports the substrate 10 placed thereon. Here, the substrate 10 may be a wafer or glass plate for manufacturing a semiconductor device or a display device of an integrated circuit device.

In the electrostatic layer 200, an electrostatic electrode 210 for generating electrostatic force is disposed to fix the substrate 10. Here, the electrostatic electrode 210 may be buried in a wide plate form inside the electrostatic layer 200. The electrostatic electrode 210 may be made of tungsten (W) or molybdenum (Mo) having a low coefficient of thermal expansion.

The electrostatic layer 200 is made of an insulating ceramic material. Specifically, the electrostatic layer 200 may be made of alumina (Al ₂ O ₃ ) or yttria (Y ₂ O ₃ ) as a base material. For example, the electrostatic layer 200 may have a form in which magnesia (MgO) or silicon oxide (SiO ₂ ) is added to alumina (Al ₂ O ₃ ) in an amount of about 90 to 96%, or about 90% or more. It may have a form in which alumina (Al ₂ O ₃ ) is added to tria (Y ₂ O ₃ ).

In this case, the electrostatic layer 200 has a volume resistance of about 10 ¹⁴ to 10 ¹⁶ Ωcm, which indicates high insulation, and may have a first heat transfer coefficient of about 10 to 30 W / (m · K).

The heat generating layer 300 is disposed under the electrostatic layer 200. The heating layer 300 is provided with a heating electrode 310 for generating heat in order to heat the substrate 10.

The heating electrode 310 has a thickness of about 0.005 to 0.3 mm, a width of about 0.5 to 10 mm, and a length of about 3 to 30 m so as to have a resistance of about 1 to 100 kPa for heating the substrate 10 to about 0 to 100 ° C. It can be configured as. Accordingly, the heating electrode 310 may be uniformly disposed in the form of a spiral or an uneven shape when viewed in plan view.

In addition, the heating electrode 310 is made of metal paste such as silver (Ag), gold (Au), nickel (Ni), tungsten (W), molybdenum (Mo), or titanium (Ti) to form the substrate 10. It is possible to implement a temperature for heating. Alternatively, the heating electrode 310 may be made of a powder material such as tungsten (W), molybdenum (Mo), or titanium (Ti), and may include gold (Au), nickel (Ni), titanium (Ti), or nitride. It may be manufactured through a thin film material such as titanium (TiN).

The heating layer 300 has a structure surrounding the side surface of the heating electrode 310. In this case, the heating layer 300 preferably has the same thickness t1 as the heating electrode 310 so as to surround all front sides of the heating electrode 310. Thus, the heat generating layer 300 is exposed to the upper and lower surfaces of the top and bottom, the top surface is in contact with the electrostatic layer 200, the bottom surface is in contact with the heat insulating layer 400. That is, the upper surface of the heating layer 300 is in contact with the lower surface of the electrostatic layer 200, and the lower surface of the heating layer 300 is in contact with the upper surface of the heat insulating layer 400.

As mentioned, when the heat generating layer 300 surrounds the side surface of the heat generating electrode 310, the thermal conductivity of the heat generating layer 300 increases, and as a result, the heat generating layer 300 itself also has an advantage of acting as a heat generating electrode. That is, since the heat generating layer 300 has a structure surrounding the side surface of the heat generating electrode 310, a portion serving as the heat generating electrode 310 is enlarged.

In addition, the thickness t1 of the heating layer 300 may be configured to be thicker than that of the heating electrode 310. At this time, when the thickness t1 of the heat generating layer 300 exceeds about 1.5 times that of the heat generating electrode 310, excessive heat is generated from the heat generating electrode 310 to heat the substrate 10 to about 0 to 100 ° C. In addition, the thickness t1 is too thick to efficiently transfer heat to the electrostatic layer 200 and the substrate 10, and the heating electrode 310 may be damaged due to excessive thermal stress. have. Therefore, the thickness t1 of the heat generating layer 300 is preferably configured to be about 1.5 times thicker than the heat generating electrode 310.

The heat generating layer 300 is made of an insulating ceramic material so as to be insulated from each other at portions facing each other of the heating electrode 310 having a spiral shape or an uneven shape. In addition, the heat generating layer 300 is less than the first heat transfer coefficient of about 10 to 30 W / (m · K) of the electrostatic layer 200 in order to spread the heat generated from the heat generating electrode 310 as uniformly as possible in the lateral direction. Has a high second heat transfer coefficient.

Accordingly, when the second heat transfer coefficient is less than about 150 W / (m · K), the rate at which heat generated from the heating electrode 310 is transferred to the substrate 10 via the heating layer 300 and the electrostatic layer 200 is increased. It is not preferable because the process time is slowed down and the process time is long, and when it exceeds about 250 W / (m · K), the heat generated from the heat generating electrode 310 passes through the heat generating layer 300 and the electrostatic layer 200 and the substrate 10. ) Is very fast, but the difference between the first and second heat transfer coefficients of each of the heating layer 300 and the electrostatic layer 200 is very large, so that the temperature variation of the heating layer 300 and the ceiling layer 200 is very high. It is not preferable because the electrostatic layer 200 accumulates fatigue due to thermal stress or heat shock.

Therefore, it is preferable that the second heat transfer coefficient is about 150 to 250 W / (m · K) so that the heat from the heat generating electrode 310 is uniformly spread on the substrate 10 in the heat generating layer 300.

To this end, the heat generating layer 300 is prepared by adding about 90% of aluminum nitride (AlN), which is superior in thermal conductivity to other ceramic materials, to which magnesia (MgO) or yttria (Y ₂ O ₃ ) are added. can do.

In detail, the heating layer 300 may be manufactured by forming the material in the form of ceramic bulk, ceramic paste, or ceramic thin film, and the like, and may be an adhesive method, a paste printing method, or a deposition method. The heat generating layer 300 manufactured as described above may have a volume resistance of about 10 ⁸ to 10 ¹⁶ cm ³ , similar to that of the electrostatic layer 200, thereby exhibiting high insulation.

As such, when the electrostatic electrode 210 is disposed, the second heat transfer coefficient higher than the first heat transfer coefficient of the heat generating layer 300 having the heat generating electrode 310 disposed below the electrostatic layer 200 having the first heat transfer coefficient is obtained. In this configuration, the heat generated from the heating electrode 310 is preferentially uniformly spread in the heating layer 300 and then provided to the substrate 10 through the electrostatic layer 200 having a relatively low first heat transfer coefficient. By doing so, the substrate 10 can be uniformly heated.

In this case, when the thickness t2 of the electrostatic layer 200 is less than about 1 mm, it is not preferable to uniformly spread the heat spread from the heat generating layer 300. The efficiency delivered to 10 is reduced, which makes it difficult to heat the substrate 10 to a desired temperature, which is undesirable. Therefore, the electrostatic layer 200 preferably has a thickness t2 of about 1 to 5 mm.

The heat insulation layer 400 is disposed under the heat generating layer 300. The heat insulation layer 400 blocks the heat generated downward from the heating electrode 310 to guide the heat upward. To this end, the heat insulation layer 400 has a third heat transfer coefficient lower than the first heat transfer coefficient of the electrostatic layer 200 as well as the second heat transfer coefficient of the heat generating layer 300.

Thus, the heat insulating layer 400 may be made of a glass-based ceramic material of a high temperature baking type such as silicon oxide (SiO ₂ ), magnesia (MgO), zinc oxide (ZnO), or the like. Alternatively, the heat insulating layer 400 may be made of a polymer material such as silicon, acrylic, epoxy, or the like, or may be made of a material in which two or more are mixed.

Accordingly, the third heat transfer coefficient of the heat insulating layer 400 may be about 0.5 to 5 W / (m · K), and may be about 10 ⁸ to 10 ¹⁶ Ωcm, similar to the electrostatic layer 200 and the heat generating layer 300. It may have a volume resistance.

On the other hand, when the thickness t3 of the heat insulation layer 400 is less than about 0.05 mm, the temperature of the substrate 10 may not be uniform due to the influence of the cooling fluid flowing in the flow path 510 of the support body 500 disposed below. In addition, since the thermal efficiency delivered to the substrate 10 is lowered, it is not preferable because a large amount of heat must be generated from the heating electrode 310 unnecessarily.

In addition, in the above case, as a relatively large amount of heat is transferred to the support body 500 disposed under the heat insulation layer 400, a large amount of cooling fluid flows into the flow path 510 or is cooled. It is not preferable because it is time consuming.

On the other hand, when the thickness t3 of the heat insulating layer 400 exceeds about 0.5 mm, there is no change in the effect of blocking heat from the heating electrode 310, which is not preferable in terms of structure. Therefore, it is preferable that the heat insulation layer 400 has a thickness t3 of about 0.05 to 0.5 mm that can effectively block heat transferred from the heating electrode 310 to the support body 500 without being thick.

The support body 500 is disposed below the heat insulation layer 400. The support body 500 supports the insulating layer 400 through the adhesive layer 600 disposed between the insulating layer 400 and serves as a pedestal as a whole.

The support body 500 has a flow path 510 uniformly distributed therein. Thus, the support body 500 may cool the heat partially transferred from the heat insulation layer 400 by flowing a cooling fluid into the flow path 510.

3 is a configuration diagram schematically illustrating a substrate processing apparatus according to an embodiment of the present invention.

In this embodiment, since the electrostatic chuck has the same configuration as that shown in FIGS. 1 and 2, the same reference numerals will be used, and detailed description thereof will be omitted.

Referring to FIG. 3, the substrate processing apparatus 1000 according to the exemplary embodiment includes a process chamber 700, a gas providing unit 800, and an electrostatic chuck 100.

The process chamber 700 provides space for processing the substrate 10 to manufacture integrated circuit devices such as semiconductor devices or display devices. For example, an etching process may be performed on the substrate 10 in the process chamber 700. At this time, the interior of the process chamber 700 may be maintained in a high vacuum state to make the etching process more smoothly.

The gas provider 800 is connected to the process chamber 700. The gas provider 800 provides a process gas 20 for processing the substrate 10 from the outside into the process chamber 700. In this case, the gas providing unit 800 may be connected to the upper portion of the process chamber 700 for smooth provision.

Here, the process gas 20 may be an inert gas for generating plasma required for the etching process, or a source gas for substantial etching. Meanwhile, a high frequency voltage may be applied to the gas providing unit 800 from the outside so that the plasma is generated inside the process chamber 700.

The electrostatic chuck 100 is disposed inside the process chamber 700. Specifically, the electrostatic chuck 100 is disposed below the process chamber 700 to fix the substrate 10 while supporting the substrate 10.

Since the electrostatic chuck 100 can uniformly heat the substrate 10 as described with reference to FIGS. 1 and 2, the semiconductor device manufactured by treating the substrate 10 through the process gas 20. Alternatively, the quality of integrated circuit devices such as display devices can be improved.

Although the detailed description of the present invention has been described with reference to the preferred embodiments of the present invention, those skilled in the art or those skilled in the art will have the idea of the present invention described in the claims to be described later. It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

Claims (12)

1. An electrostatic layer having a first heat transfer coefficient while an electrostatic electrode generating electrostatic force is disposed to fix the substrate placed thereon; And

   An electrostatic chuck disposed under the electrostatic layer, the heat generating layer having a second heat transfer coefficient higher than the first heat transfer coefficient while a heat generating electrode for heating the substrate is disposed.
2. The electrostatic chuck of claim 1, wherein the heating layer is made of a ceramic material including aluminum nitride (AlN), magnesia (MgO), yttria (Y ₂ O ₃ ), or a mixture thereof.
3. The electrostatic chuck of claim 1, wherein the second heat transfer coefficient is 150 to 250 W / (m · K).
4. The electrostatic chuck of claim 1, wherein the heat generating layer has the same thickness as the heat generating electrode and has a structure surrounding a side surface of the heat generating electrode.
5. The electrostatic chuck of claim 1, wherein the electrostatic layer has a thickness of 1 to 5 mm.
6. The electrostatic chuck of claim 1, wherein an upper surface of the heat generating layer has a structure in contact with a lower surface of the electrostatic layer.
7. The electrostatic chuck of claim 1, further comprising a heat insulation layer disposed under the heat generating layer and having a third heat transfer coefficient lower than the first heat transfer coefficient.
8. The electrostatic chuck of claim 7, wherein the heat insulation layer has a thickness of 0.05 to 0.5 mm.
9. The electrostatic chuck of claim 7, wherein the heat insulation layer has a structure in which an upper surface thereof is in contact with a lower surface of the heat generating layer.
10. A process chamber providing space for processing a substrate;

    A gas provider connected to the process chamber and providing a process gas to process the substrate into the process chamber; And

    An electrostatic chuck disposed in the process chamber and supporting and fixing the substrate processed through the process gas,

    The electrostatic chuck is

    An electrostatic layer having a first heat transfer coefficient on which the substrate is placed, wherein an electrostatic electrode for generating electrostatic force for fixing the substrate is disposed; And

    And a heat generating layer disposed under the electrostatic layer, the heat generating layer having a second heat transfer coefficient higher than the first heat transfer coefficient while the heat generating electrode for heating the substrate is disposed.
11. The substrate treating apparatus of claim 10, wherein the heat generating layer has a same thickness as the heat generating electrode and has a structure surrounding a side surface of the heat generating electrode.
12. The substrate processing apparatus of claim 10, wherein an upper surface of the heat generating layer is disposed in contact with a lower surface of the electrostatic layer, and a lower surface of the heat generating layer is disposed in contact with an upper surface of the heat insulating layer.

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