BIPOLAR ELECTROSTATIC CHUCK HAVING ELECTRODE ON PORTION THEREOF

Technical Field

[0Q01] The present disclosure relates to a bipolar electrostatic chuck, and more particularly, to a bipolar electrostatic chuck for holding a large-area substrate using an electrostatic force.

Background Art

[00Q2] A wafer or a substrate (e.g , a glass substrate) as an object to be processed is subjected to various processing procedures such as etching, CVD, sputtering, ion implantation, ashing and/or evaporation deposition in a process of manufacturing a semiconductor, a display panel, or the like. In such a case, stable holding of an object to be processed is required, and a mechanical damp or a vacuum chuck may be used for this purpose, but an electrostatic chuck is also widely used.

[0003] An electrostatic chuck (ESC) uses an electrostatic force between two objects having different electrical potentials. A conventional general electrostatic chuck is configured in a structure including a metal plate, a dielectric layer stacked on the upper side of the metal plate via an organic adhesive such as a silicone resin, and electrodes formed in the dielectric layer.

[0QQ4] An electrostatic chuck in which the electrodes formed in the dielectric layer have a single polarity of is referred to as a monopolar electrostatic chuck (a monopolar ESC or a unipolar ESC), and an electrostatic chuck in which the electrodes have two polarities different from each other is referred to as a bipolar electrostatic chuck (a bipolar ESC).

[0QQ5] Meanwhile, as recent wafers or glass substrates have become larger, electrostatic chucks have also become larger, and a method of forming a dielectric layer and electrodes using plasma spraying has been used in the manufacture of electrostatic chucks. [0006] A chucking force is one of the first factors to be considered in manufacturing an electrostatic chuck. When the supplied electric energy (amount of accumulated electric charges) is the same, the electrostatic force increases as the area of the electrodes increases. Thus, in a conventional electrostatic chuck, electrodes are made to occupy a significant proportion of the total area of the electrostatic chuck.

[0007] This tendency appears in both the conventional monopolar electrostatic chuck and the bipolar electrostatic chuck. In particular, in the bipolar electrostatic chuck, electrodes are formed over the total area of the electrostatic chuck, and the tendency becomes more pronounced.

[0008] However, as electrostatic chucks are enlarged in area, when the specific gravity and position of the area in which the electrodes are formed are not carefully considered, the total cost of manufacturing the electrostatic chucks is increased and an inappropriately excessive chucking force, which may be harmful to a wafer or a substrate, may be applied to the wafer or the substrate.

[0009] In addition, when a substrate is processed using an electrostatic chuck having a large area, there is a high possibility of the occurrence of stains due to a temperature deviation or a potential difference in a processing chamber, and the development of an electrostatic chuck capable of solving such a problem is required

[0010] ⁴ Prior Art Document

(Patent Document 1) Korean Patent No. 10-1797927 (registered on Nov 09, 2017); and

(Patent Document 2) Korean Patent No. 10-1775135 (registered on Aug. 30, 2017). Detailed Description of the invention

Technical Problem

[0011] An aspect of the present disclosure is to provide a bipolar electrostatic chuck capable of providing an appropriate holding force while lowering manufacturing costs and preventing the occurrence of stains on a substrate in a substrate processing process.

Technical Solution

[0012] In order to achieve the aspects described above, there is provided a bipolar electrostatic chuck for holding a large-area substrate, particularly wherein each side of which has a size of 2000 mm or larger. The bipolar electrostatic chuck may include: a base; a lower dielectric layer formed on the upper surface of the base, particularly the entire upper surface of the base; an edge electrode part formed along a rim on an upper side of the lower dielectric layer, the edge electrode part including a first electrode and a second electrode, which is spaced apart from the first electrode and has a polarity different from the polarity of the first electrode; and an upper dielectric layer formed on an upper side of the lower dielectric layer and the edge electrode part, in which, in a plan view, the bipolar electrostatic chuck is divided into an edge electrode forming area, which corresponds to an area from corners to the edge electrode part, and a central area, which corresponds to an area other than the edge electrode forming area.

[0013] In the bipolar electrostatic chuck according to the present disclosure, the area (A) of the edge electrode forming area may be in a range of 20% to 35% of a total area of the bipolar electrostatic chuck.

[0Q14] The bipolar electrostatic chuck according to the present disclosure may further include a center electrode part formed in an exact center thereof on the upper side of the lower dielectric layer and including a third electrode and a fourth electrode, which is spaced apart from the third electrode and has a polarity different from the polarity of the third electrode, in which the upper dielectric layer may be formed on the upper side of the lower dielectric layer, the edge electrode part, and the center electrode part, and, in the plan view, the area (B) of a center electrode forming area defined by an outer boundary of the center electrode part may be in the range of 2% to 5% of the total area of the bipolar electrostatic chuck

[0015] In the bipolar electrostatic chuck according to the present disclosure, when the total area is in the range of 2200 mm * 2500 mm to 3100 mm * 3400 mm, the edge electrode forming area may have a width of 200mm and the center electrode forming area may have an area of 300mm * 300mm.

[OQ183 In the bipolar electrostatic chuck according to the present disclosure, the upper dielectric layer may include a first upper dielectric layer formed on the edge electrode part, and a second upper dielectric layer connected to the lower dielectric layer in the central area, and the first upper dielectric layer may have a dielectric constant higher than the dielectric constant of the second upper dielectric layer or a specific resistance value smaller than the specific resistance value of the second upper dielectric layer.

[0Q17] In the bipolar electrostatic chuck according to the present disclosure, the upper dielectric layer may include a first upper dielectric layer formed on the edge electrode part, a second upper dielectric layer connected to the lower dielectric layer in the central area, and a third upper dielectric layer formed on the upper side of the center electrode part, in which the first upper dielectric layer and the third upper dielectric layer have a dielectric constant higher than the dielectric constant of the second upper dielectric layer or a specific resistance value lower than the specific resistance value of the second upper dielectric layer.

[0018] In the bipolar electrostatic chuck according to the present disclosure, the upper dielectric layer may include a fourth upper dielectric layer connected to the lower dielectric layer in the central area, and a fifth upper dielectric layer formed on an upper side of the edge electrode part and the fourth upper dielectric layer, in which the fifth upper dielectric layer may have a dielectric constant higher than a dielectric constant of the fourth upper dielectric layer or a specific resistance value smaller than the specific resistance value of the fourth upper dielectric layer. [0Q19] In the bipolar electrostatic chuck according to the present disclosure, the upper dielectric layer may include a fourth upper dielectric layer connected to the lower dielectric layer in the central area, and a sixth upper dielectric layer formed on the upper side of the edge electrode part, the center electrode part, and the fourth upper dielectric layer, in which the sixth upper dielectric layer may have a dielectric constant higher than the dielectric constant of the fourth upper dielectric layer or a specific resistance value smaller than the specific resistance value of the fourth upper dielectric layer.

[0020] In the bipolar electrostatic chuck according to the present disclosure, the upper dielectric layer may include a first concave part, which serves as a boundary between the edge electrode forming area and the central area and has a concave upper surface, and a second concave part, which extends across the central area and has a concave upper surface.

[0021] In the bipolar electrostatic chuck according to the present disclosure, the upper dielectric layer may include a first concave part, which serves as a boundary between the edge electrode forming area and the central area and has a concave upper surface, a second concave part, which extends across the central area and has a concave upper surface, and a third concave part, which serves as a boundary between the central area and the center electrode forming area and has a concave upper surface

[0022] In the bipolar electrostatic chuck according to the present disclosure, the second upper dielectric layer may be formed of AI ₂ O ₃ , and the first upper dielectric layer and the third upper dielectric layer may be formed of A! ₂ G ₃ to which particles of at least one selected from among TiC, TiG ₂ , Cr ₂ 0 ₃ , MnOa, COC, and CuO are added

[0Q23] In the bipolar electrostatic chuck according to the present disclosure, the first upper dielectric layer, the second upper dielectric layer, and the third upper dielectric layer may have a surface roughness (Ra) of 2 to 3.5 pm or 0.8 pm. Advantageous Effects

[0Q24] According to the present disclosure, it is possible to provide a bipolar electrostatic chuck capable of optimizing functions while lowering manufacturing costs, and capable of preventing the occurrence of stains due to a temperature variation or a potential difference during the process of manufacturing a substrate.

Brief Description of the Drawings

[0Q25] FIG. 1A is a plan view schematically illustrating a bipolar electrostatic chuck according to an embodiment of the present disclosure;

[0026] FIG. 1 B is a cross-sectional view schematically illustrating a bipolar electrostatic chuck of FIG. 1A;

[0Q27] FIG. 2A is a plan view schematically illustrating a bipolar electrostatic chuck according to another embodiment of the present disclosure;

[0028] FIG. 2B is a cross-sectional view schematically illustrating a bipolar electrostatic chuck of FIG, 2A;

[0029] FIG. 3A and 3B are cross-sectional views schematically illustrating a bipolar electrostatic chuck according to still another embodiment of the present disclosure; FIG. 4A is a perspective view schematically illustrating a bipolar electrostatic chuck according to still another embodiment of the present disclosure;

[0030] FIG. 4B is a cross-sectional view schematically illustrating a bipolar electrostatic chuck of FIG. 4A;

[0031] FIG. 5A is a perspective view schematically illustrating a bipolar electrostatic chuck according to yet another embodiment of the present disclosure; and [0Q32] FIG. 5B is a cross-sectional view schematically illustrating a bipolar electrostatic chuck of FIG. 5A.

Descriptions of Reference Numerals of Drawings

[0Q33] 1 : bipolar electrostatic chuck, 10: base,

[0034] 20: lower dielectric layer, 30: edge electrode part,

[0035] 31 : first electrode, 32: second electrode,

[0036] 40: center electrode part, 41 : third electrode, 42: fourth electrode, 50: upper dielectric layer, 51 : first upper dielectric layer, 52: second upper dielectric layer,

[0037] 53: third upper dielectric layer, 54: fourth upper dielectric layer,

[0038] 55: fifth upper dielectric layer, 56: sixth upper dielectric layer,

[0039] 57: first concave part, 58: second concave part, 59: third concave part, T1 : edge electrode forming area,

[0040] T2: center electrode forming area, T3: central area

Mode for Carrying Out the invention

[0041] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. However, in the following description of the present disclosure, descriptions of well-known functions or constructions will be omitted in order to make the gist of the present disclosure clear.

[0042] FIG. 1A and 1 B show a plan view (FIG. 1A) and a cross- sectional view (FIG. 1 B) schematically illustrating a bipolar electrostatic chuck 1 according to an embodiment of the present disclosure, and FIG. 2A and 2B show a plan view (FIG. 2A) and a cross-sectional view (FIG. 2B) schematically illustrating a bipolar electrostatic chuck 1 according to another embodiment of the present disclosure. [0Q43] FIGS. 1A to 2B are schematic and are partially exaggerated for convenience of description of the technical features of a bipolar electrostatic chuck 1 according to the present disclosure, and this is also the same in FIGS. 3A to 5B. The bipolar electrostatic chuck 1 according to the present disclosure has the technical features described in the present disclosure, and of course, shapes, patterns, specifications, and the like can be variously formed.

[0044] A bipolar electrostatic chuck having electrodes on a portion thereof (hereinafter, referred to as a“bipolar electrostatic chuck 1”) according to the present disclosure relates to an electrostatic chuck 1 , which is configured to hold a wafer or a substrate as an object to be processed in a process of manufacturing a semiconductor or a display panel using an electrostatic force, and which is suitable for holding a large-area substrate bipolar electrostatic chuck 1 , in particular for holding a large-area substrate constituting an Organic Light-Emitting Diode (OLED) display panel.

[0045] The bipolar electrostatic chuck 1 according to the present disclosure includes a base 10, a lower dielectric layer 20, an electrode part (an edge electrode part 30 and a center electrode part 40), and an upper dielectric layer 50. Hereinafter, the side on which the base 10 is formed will be referred to as a lower side, and the side on which the upper dielectric layer 50 is formed will be referred to as an upper side.

[0048] The bipolar electrostatic chuck 1 according to the present disclosure may include a base 10, a lower dielectric layer 20, an edge electrode part 30 and an upper dielectric layer 50 (see FIG. 1 B), which are laminated in the vertical direction. Alternatively, the bipolar electrostatic chuck 1 may include a base 10, a lower dielectric layer 20, an edge electrode part 30, a center electrode part 40, and an upper dielectric layer 50 (see FIG. 2B), which are laminated in the vertical direction.

[0Q47] In recent years, demand for large-area displays has been steadily increasing, and an increase in the size of glass substrates is also required in order to improve a chamfering rate during the manufacture of display panels. The sizes of substrates for manufacturing display panels may be classified by generation. For example, substrates used for 8 ^th generation panels may have a size of 2200 mm * 2500 m, substrates used for 10 ^th generation panels may have a size of 2940 mm * 3340 mm, and substrates used for 11 ^th generation panels may have a size of 3000 mm * 3320 mm.

[0Q48] It is required that the bipolar electrostatic chuck 1 of the present disclosure used for holding such a large-area substrate S (a substrate, each side of which has a length of 2000 mm or more) also be large, and in a plan view, the total area (see FIG. 1A and FIG. 2A) may have a size of 2200 mm * 2500 mm or more (d1 * d2), or the total area may be in the range of 2200 mm * 2500 mm to 3100 mm * 3400 mm. Specifically, the bipolar electrostatic chuck 1 of the present disclosure may have a size of 2980 mm * 3280 mm.

[0049] The base 10 may be made of various materials ensuring sufficient mechanical rigidity, and is preferably made of a metal material. Specifically, the base 10 may be made of aluminum, stainless steel, or the like. The base 10 is in the form of a rectangular plate as a whole.

[0050] The lower dielectric layer 20 may formed on the entire upper surface of the base 10, and may be laminated on and bonded to the base 10. The lower dielectric layer 20 forms an insulating layer between the base 10 and the electrode part (the edge electrode part 30 and the center electrode part 40). The lower dielectric layer 20 may be formed of various dielectric materials having an insulating property, and may be formed of a ceramic material. In this case, the lower dielectric layer 20 may be formed on the upper surface of the base 10 through a plasma spraying method, a sol-gel method, or the like. More specifically, the lower dielectric layer 20 may be made of a material selected from or a combination of AI ₂ q ₃ , Y ₂ O ₃ , Zr0 ₂ , MgO, SIC, AIN, SL ₃ N ₄ , and Si0 ₂ . In particular, the lower dielectric layer 20 may be made of Al ₂ 0 ₃ .

[0Q51] The edge electrode part 30 may be made of a conductor, particularly tungsten. The edge electrode part 30 is electrically connected to a separately provided DC power supply. The formation of the DC power supply and the connection of the DC power supply with the electrode part (the edge electrode part 30 and the center electrode part 40) may be implemented through various known methods.

[0052] The edge electrode part 30 is divided into first electrodes 31 and second electrodes 32, which are spaced apart from each other, and may have different polarities during the supply of electric energy through the DC power supply. That is, when the positive (+) polarity is applied to the first electrodes 31 , the negative (-) polarity is applied to the second electrodes 32.

[0053] The edge electrode part 30 is formed on the upper side of the lower dielectric layer 20, and may be formed through plasma spraying or the like. In this case, the first electrodes 31 and the second electrodes 32, which form the edge electrode part 30, may be formed in various known patterns.

[0Q54] The upper dielectric layer 50 is formed on the upper side of the lower dielectric layer 20 and the edge electrode 30 and is laminated on and bonded to the lower dielectric layer 20 and the edge electrode part 30. The upper dielectric layer 50 constitutes the entire upper surface of the bipolar electrostatic chuck 1 , and the upper surface of the upper dielectric layer 50 is brought into contact with the substrate S. As the upper dielectric layer 50 is formed, the edge electrode part 30 is buried between the lower dielectric layer 20 and the upper dielectric layer 50.

[0Q55] The upper dielectric layer 50 may be formed of various dielectric materials having an insulating property, and may be formed of a ceramic material in this case, the upper dielectric layer 50 may be formed on the upper side of the lower dielectric layer 20 and the edge electrode part 30 through a plasma spraying method, a sol-gel method, or the like. The upper dielectric layer 50 may be made of the same material and through the same method as the lower dielectric layer 20.

[0056] The upper dielectric layer 50 is preferably formed to have a uniform deposition height and surface roughness over the entire area thereof. Specifically, the surface roughness Ra of the upper dielectric layer 50 may have any value in the range of 2 to 3.5 ym or may have a value of 0.8 ym.

[0057] In the present disclosure, the edge electrode part 30 is not formed over the entire area of the bipolar electrostatic chuck 1 , but is formed in a partial area, particularly along the rim of the electrostatic chuck 1. In a plan view (that is, when viewing the bipolar electrostatic chuck 1 from above), the edge electrode part 30 is formed only in the rim portion of the bipolar electrostatic chuck 1 and not in the central portion of the bipolar electrostatic chuck.

[0Q58] Accordingly, in the present disclosure, the bipolar electrostatic chuck 1 may be divided into an edge electrode forming area T1 in which the edge electrode part 30 is formed from the edges of the bipolar electrostatic chuck 1 and a central area T3 other than the edge electrode forming area T1 , and a boundary b1 between the edge electrode forming area T1 and the central area T3 is formed.

[0053] The area (A) of the edge electrode forming region T 1 may be set to satisfy the range of 20% to 35% of the total area of the bipolar electrostatic chuck 1 , and the width d3 of the edge electrode forming area Ϊ1 may be made constant along the entire rim of the bipolar electrostatic chuck 1.

[0060] In the present disclosure, when the total area (d1 * d2) of the bipolar electrostatic chuck 1 is 2200 mm * 2500 mm to 3100 mm * 3400 mm, the edge electrode forming area T1 is formed to have a predetermined width d3 of 200 mm along the rim of the bipolar electrostatic chuck 1.

[0061] With the above-mentioned configuration, in the bipolar electrostatic chuck 1 according to the present disclosure, an electrostatic force may be rapidly generated along the rim portion and a potential difference may not be generated, and when the substrate S is chucked, a uniform and stable chucking force is applied along the rim portion of the substrate S. [0Q62] As described above, since the electrodes are not formed over the entire area of the bipolar electrostatic chuck 1 in the present disclosure, it is possible to provide an appropriate holding force while reducing manufacturing costs it is also possible to prevent the occurrence of a temperature deviation or a potential difference, so that the occurrence of stains on the substrate S can be effectively prevented.

[Goes] Meanwhile, as described above, the bipolar electrostatic chuck 1 according to the present disclosure may further include a center electrode part 40 in addition to the edge electrode part 30. in this case, the base 10, the lower dielectric layer 20, the edge electrode part 30, and the upper dielectric layer 50 may be made of the same material and through the same method as described above. However, the upper dielectric layer 50 is formed on the upper side of the lower dielectric layer 20, the edge electrode part 30, and the center electrode part 40 (see FIG. 2B), and is laminated on and bonded to the lower dielectric layer 20, the edge electrode part 30, and the center electrode part 40.

[0064] The edge electrode part 30 and the center electrode part 40 are embedded between the lower dielectric layer 20 and the upper dielectric layer

[0Q65] The center electrode part 40 is preferably formed in the center on the upper side of the lower dielectric layer 20, and may be made of a conductor, particularly tungsten. The center electrode part 40 is electrically connected to the DC power supply.

[0066] The center electrode part 40 is divided into third electrodes 41 and fourth electrodes 42, which are spaced apart from each other and have different polarities during the supply of electric energy through the DC power supply. That is, when the positive (+) polarity is applied to the third electrodes 41 , the negative {-) polarity is applied to the fourth electrodes 42.

[0067] The center electrode part 40 is formed on the upper side of the lower dielectric layer 20, and may be formed through plasma spraying or the like in this case, the third electrodes 41 and the fourth electrodes 42, which form the center electrode part 40, may be formed in various known patterns

[0068] In a plan view, the area (B) of the center electrode forming area

T2 defined by the outer boundary b2 of the center electrode part 40 may be set to satisfy the range of 2% to 5% of the total area of the bipolar electrostatic chuck 1 (d1 * d2).

[0089] In the present disclosure, when the total area of the bipolar electrostatic chuck 1 is 2200 mm * 2500 mm to 3100 mm * 3400 mm, the center electrode forming area T2 (d4 * d5) may be set to have a size of 300 mm * 300 mm in the center of the bipolar electrostatic chuck 1.

[0070] With this configuration, in the bipolar electrostatic chuck 1 according to the present disclosure, a uniform and stable chucking force is applied along the rim of the substrate S during chucking of the substrate S. in addition, an auxiliary chucking force acts on the central portion of the substrate S, so that the substrate S can be fixed more stably.

[0071] In this case, it is also possible to prevent the occurrence of a temperature deviation or a potential difference, so that the occurrence of stains on the substrate S in a substrate processing process can be effectively prevented.

[0072] FIGS 3A and 3B show cross-sectional views schematically illustrating a bipolar electrostatic chuck 1 according to still another embodiment of the present disclosure. When the bipolar electrostatic chuck 1 according to the present disclosure includes a base 10, a lower dielectric layer 20, an edge electrode part 30, and an upper dielectric layer 50, the upper dielectric layer 50 may be divided into a first upper dielectric layer 51 and a second upper dielectric layer 52 (see FIG. 3A).

[0073] The first upper dielectric layer 51 is a portion formed on the edge electrode part 30, and the second upper dielectric layer 52 is a portion connected to the lower dielectric layer 20 in the central area T3 [0Q74] Each of the first upper dielectric layer 51 and the second upper dielectric layer 52 may be formed of a dielectric material having an insulating property, and may be formed of a ceramic material. In this case, the first upper dielectric layer 51 and the second upper dielectric layer 52 may be formed through a plasma welding method, a sol-gel method, or the like.

[0Q75] The first upper dielectric layer 51 and the second upper dielectric layer 52 are formed individually, and it is preferable to form one of them and then to form the other. Of course, after the first upper dielectric layer 51 and the second upper dielectric layer 52 are formed, a separate surface processing may be performed in order to secure a constant height and surface roughness Ra of the entire upper dielectric layer 50.

[0076] In the bipolar electrostatic chuck 1 according to the present disclosure, the first upper dielectric layer 51 may have a dielectric constant higher than that of the second upper dielectric layer 52 or a specific resistance value smaller than that of the second upper dielectric layer 52. The second upper dielectric layer 52 may be made of AI2O3, Y2O3, ZrG ₂ , MgO, SiC, AIN, Si ₃ N ₄ , Si02, and so on, and the first upper dielectric layer 51 may be made in the form in which particles formed of at least one of TIC, Ti0 ₂ , Cr ₂ 0 ₃ , MnC , CoC, and CuO are added to a base material such as AI ₂ q3, Y2O3, Zr0 _2, MgO, SiC, AIN, S13N4, or Si0 ₂ . Preferably, the second upper dielectric layer 52 may be made of Ai ₂ 0 ₃ , and the first upper dielectric layer 51 may be made of Al ₂ 0 ₃ to which particles of at least one of TIC, Ti0 ₂ , Cr ₂ 0 ₃ , Mn0 ₂ , CoC, and CuO are added.

[0077] Meanwhile, when the bipolar electrostatic chuck 1 according to the present disclosure includes a base 1 0, a lower dielectric layer 20, an edge electrode part 30, a center electrode part 40, and an upper dielectric layer 50, the upper dielectric layer 50 may be divided into a first upper dielectric layer 51 , a second upper dielectric layer 52, and a third upper dielectric layer 53 (see FIG 3B).

[8078] Here, the first upper dielectric layer 51 is a portion formed on the edge electrode part 30, the third upper dielectric layer 53 is a portion formed on the center electrode part 40, and the second upper dielectric layer 52 is a portion connected to the lower dielectric layer 20 in the central area T3.

[OQ733 Each of the first upper dielectric layer 51 , the second upper dielectric layer 52, and the third upper dielectric layer 53 may be formed of a dielectric material having an insulating property, and may be formed of a ceramic material. In this case, the first upper dielectric layer 51 , the second upper dielectric layer 52, and the third upper dielectric layer 53 may be formed through a plasma welding method, a sol-gel method, or the like.

[0080] The first upper dielectric layer 51 , the second upper dielectric layer 52 and the third upper dielectric layer 53 may be formed individually. However, it is preferable to form the first upper dielectric layer 51 and the third upper dielectric layer 53 together. Of course, after the first upper dielectric layer 51 , the second upper dielectric layer 52, and the third upper dielectric layer 53 are formed, separate surface processing may be performed in order to secure a constant surface roughness Ra of the upper dielectric layer 50.

[0Q81] In the bipolar electrostatic chuck 1 according to the present disclosure, the first upper dielectric layer 51 and the third upper dielectric layer 53 may have a dielectric constant higher than that of the second upper dielectric layer 52 or a specific resistance value smaller than that of the second upper dielectric layer 52. The second upper dielectric layer 52 may be made of AbOs, Y2O3, ZrC >2, MgO, SIC, AIN, S13N4, SIC >2, and so on, and the first upper dielectric layer 51 and the third upper dielectric layer 53 may be made in the form in which particles formed of at least one of TIC, Ti0 ₂ , OG ₂ (¾, Mn0 ₂ , CoC, and CuO are added to a base material such as AI ₂ 0 ₃ , Y2O3, ZrG ₂ , MgO, SiC, AIN, ShN,*, or SI0 ₂ . Preferably, the second upper dielectric layer 52 may be made of AbCA, and the first upper dielectric layer 51 and the third upper dielectric layer 53 may be made of AI ₂₍ ¾ to which particles of at least one of TIC, Ti0 ₂ , Cr ₂ 03, Mn0 ₂ , CoC, and CuO are added.

[0Q82] With this configuration, it is possible to increase the electrostatic force in the edge electrode forming area T1 (or the edge electrode forming area T1 and the center electrode forming area T2) under the same power supply and electrode conditions, it is possible to reduce the possibility of charge accumulation due to the leakage current in the central area T3 (in the case where the center electrode forming area T2 is provided, the central area T3 except for the center electrode forming area T2), and chucking and dechucking of the substrate S are able to be performed more stably and effectively.

[0083] FIGS 4A and 4B show a perspective view (FIG. 4A) and a cross-sectional view (FIG. 4B) schematically illustrating a bipolar electrostatic chuck 1 according to still another embodiment of the present disclosure, and FIGS. 5A and 5B show a perspective view (FIG. 5A) and a cross-sectional view (FIG. 5B) schematically illustrating a bipolar electrostatic chuck 1 according to yet another embodiment of the present disclosure.

[0084] When the bipolar electrostatic chuck 1 according to the present disclosure includes a base 10, a lower dielectric layer 20, an edge electrode part 30, and an upper dielectric layer 50, the upper dielectric layer 50 may be divided into a fourth upper dielectric layer 54 and a fifth upper dielectric layer 55 (see FIG. 4A and 4B).

[0085] At this time, the upper dielectric layer 50 may further include a first concave part 57 and a second concave part 58.

[0088] The fourth upper dielectric layer 54 is a portion connected to the lower dielectric layer 20 in the central area T3, and the fifth upper dielectric layer 55 is a portion formed on the upper side of the edge electrode part 30 and the fourth upper dielectric layer 54.

[0087] Each of the fourth upper dielectric layer 54 and the fifth upper dielectric layer 55 may be formed of a dielectric material having an insulating property, and may be formed of a ceramic material in this case, the fourth upper dielectric layer 54 and the fifth upper dielectric layer 55 may be formed through a plasma welding method, a sol-gel method, or the like. [0Q88] Of course, the fifth upper dielectric layer 55 is formed after forming the fourth upper dielectric layer 54, and it is preferable to form the fourth upper dielectric layer 54 to have a height, which is the same as or higher than that of the edge electrode part 30.

[0Q89] In the bipolar electrostatic chuck 1 according to the present disclosure, the fifth upper dielectric layer 55 may have a dielectric constant higher than that of the fourth upper dielectric layer 54 or a specific resistance value smaller than that of the fourth upper dielectric layer 54. The fourth upper dielectric layer 54 may be made of AI4O5, Y2O3, Zr0 ₂ , MgO, SIC, AIN, Si3N ₄ , SiG ₂ , and so on, and the fifth upper dielectric layer 55 may be made in the form in which particles formed of at least one of TiC, Ti0 ₂ , Cr ₂ 03, Mn0 ₂ , CoC, and CuO are added to a base material such as Ai ₂ 03, Y ₂ 03, Zr0 ₂ , MgO, SiC, AIN, S1 ₃ N ₄ , or Si0 ₂ . Preferably, the fourth upper dielectric layer 54 may be made of A! ₂ q3, and the fifth upper dielectric layer 55 may be made of AI ₂ G ₃ to which particles of at least one of TiC, Ti0 ₂ , Cr ₂ G ₃ , Mn0 ₂ , CoC and CuO are added.

[0090] The first concave part 57 forms a boundary between the edge electrode forming area T1 and the central area T3 and is formed in the shape of a concave groove in the upper surface of the upper dielectric layer 50 It is preferable to form the first concave part 57 to extend to the upper end surface of the fourth upper dielectric layer 54, and along the first concave part 57, the fifth upper dielectric layer 55 is physically divided into the part of the edge electrode forming area T1 and the part of the central area T3

[0091] The second concave part 58 extends across the central area T3, and is formed in the shape of a concave groove in the upper surface of the upper dielectric layer 50.

[0092] In addition, when the bipolar electrostatic chuck 1 according to the present disclosure includes a base 10, a lower dielectric layer 20, an edge electrode part 30, a center electrode part 40, and an upper dielectric layer 50, the upper dielectric layer 50 may be divided into a fourth upper dielectric layer 54 and a sixth upper dielectric layer 56 (see FIG. 5A and 5B). [0Q93] At this time, the upper dielectric layer 50 may further include a first concave part 57, a second concave part 58, and a third concave part 59.

[0094] As described above, the fourth upper dielectric layer 54 is a portion connected to the lower dielectric layer 20 in the central area T3, and the sixth upper dielectric layer 56 is a portion formed on the upper side of the edge electrode part 30, the center electrode part 40, and the fourth upper dielectric layer 54.

[0095] Each of the fourth upper dielectric layer 54 and the sixth upper dielectric layer 56 may be formed of a dielectric material having an insulating property, and may be formed of a ceramic material in this case, the fourth upper dielectric layer 54 and the sixth upper dielectric layer 56 may be formed through a plasma welding method, a sol-gel method, or the like.

[0096] Of course, the sixth upper dielectric layer 56 is formed after forming the fourth upper dielectric layer 54, and it is preferable to form the fourth upper dielectric layer 54 to have a height, which is the same as or higher than those of the edge electrode part 30 and the central electrode part 40.

[0Q97] In the bipolar electrostatic chuck 1 according to the present disclosure, the sixth upper dielectric layer 56 may have a dielectric constant higher than that of the fourth upper dielectric layer 54 or a specific resistance value smaller than that of the fourth upper dielectric layer 54, and the sixth upper dielectric layer 56 may be made of the same material as the above- described fifth upper dielectric layer 55

[0098] The first concave part 57 forms a boundary between the edge electrode forming area T1 and the central area T3 and is formed in the shape of a concave groove in the upper surface of the upper dielectric layer 50. It is preferable to form the first concave part 57 to extend to the upper end surface of the fourth upper dielectric layer 54, and along the first concave part 57, the sixth upper dielectric layer 56 is physically divided into the part of the edge electrode forming area T 1 and the part of the central area T3. [0Q99] The second concave part 58 extends across the central area T3, and is formed in the shape of a concave groove in the upper surface of the upper dielectric layer 50

[00100] The third concave part 59 forms a boundary between the centra! area T3 and the center electrode forming area T2 and is formed in the shape of a concave groove in the upper surface of the upper dielectric layer 50. It is preferable to form the third concave part 59 so as to extend to the upper end surface of the fourth upper dielectric layer 54, and along the third concave part 59, the sixth upper dielectric layer 58 is physically divided into the part of the central area T3 and the part of the center electrode forming area T2.

[8Q181] With this configuration, it is possible to improve the electrostatic force in the edge electrode forming area T1 (or the edge electrode forming area T1 and the center electrode forming area T2) under the same power supply and electrode conditions, it is possible to reduce the possibility of charge accumulation due to the leakage current in the central area T3 (in the case where the center electrode forming area T2 is provided, the central area T3 except for the center electrode forming area T2), and chucking and dechucking of the substrate S are able to be performed more effectively.

[00102] Since the upper dielectric layer 50 includes the first concave part 57 and the second concave part 58 or includes the first concave part 57, the second concave part 58, and the third concave part 59, it is possible to prevent the occurrence of stains due to a temperature variation more effectively, and the concave parts are able to help smooth movement of an insulating gas, such as helium, filled in a space between the substrate S and the bipolar electrostatic chuck 1.

[0Q103] Although specific embodiments of the present disclosure have been described and illustrated above, it is evident to a person ordinarily skilled in the art that the present disclosure is not limited to the described embodiments, and various changes and modifications can be made without departing from the technical idea and scope of the present disclosure. Accordingly, such modifications or variations should not be understood separately from the technical spirit and viewpoint of the present disclosure, and the modifications and variations should be deemed to fail within the scope of the claims of the present disclosure.

Industrial Applicability

[00104] With a bipolar electrostatic chuck having electrodes on a portion thereof according to the present disclosure, it is possible to provide a bipolar electrostatic chuck which has optimized functions at reduced manufacturing cost and is capable of preventing the occurrence of stains due to a temperature variation or a potential difference during the process of manufacturing a substrate. In this point of view, since the present disclosure overcomes the limits of existing technologies, there is a good chance that an apparatus to which the present disclosure is applied will be commercially available or will be marketed without being limited to an apparatus that uses the related technique of the present disclosure. Further, it is evident that it is possible to carry out the present disclosure in practice. Thus, the present disclosure can be industrially used.