Low Temperature Electrostatic Chuck

Abstract

The present disclosure relates to a low-temperature electrostatic chuck, and a technical problem to be solved is to provide a low-temperature electrostatic chuck that can be attached to equipment and prevents the formation of frost, ice, moisture, etc. on the equipment. To this end, the present disclosure provides a low-temperature electrostatic chuck including a base member and a support member including a first dielectric layer coated on the base member, an electrode layer provided on the first dielectric layer, and a second dielectric layer coated on the first dielectric layer and the electrode layer, the base member including a first flow path through which a first fluid at a first temperature provided to an upper region flows, and a second flow path through which a second fluid at a second temperature higher than the first temperature provided to a lower region flows.

Description

[Technical field]

[0001] The present disclosure relates to low temperature electrostatic chucks. [Background technology]

[0002] 2. Description of the Related Art Generally, semiconductor devices are manufactured through a number of unit processes, including a thin film deposition process and an etching process. The etching process is mainly performed using a plasma etching apparatus in which a plasma reaction is induced.

[0003] In recent years, plasma etching has been required to be performed at low temperatures to form structures having a high aspect ratio or to ensure high selectivity when etching a wafer using a photoresist film.

[0004] Due to such low temperature etching, the electrostatic chuck also becomes cold, which causes various problems in the equipment to which the electrostatic chuck is attached and mounted. For example, since the electrostatic chuck is cold and the equipment is at room temperature, frost, ice, or water may form on the equipment. Such moisture may affect various mechanical / electrical structures of the equipment, and may ultimately cause wafer defects.

[0005] The above information disclosed in the Background of the Invention is intended to enhance understanding of the background of the present invention only, and may therefore include information that does not constitute prior art. Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present disclosure is to provide a low-temperature electrostatic chuck that can be attached to equipment and prevents the formation of frost, ice, moisture, or the like on the equipment. [Means for solving the problem]

[0007] The low-temperature electrostatic chuck according to the present disclosure includes a base member; and a support member including a first dielectric layer coated on the base member, an electrode layer provided on the first dielectric layer, and a second dielectric layer coated on the first dielectric layer and the electrode layer; the base member may include a first flow path through which a first fluid at a first temperature provided to an upper region flows, and a second flow path through which a second fluid at a second temperature higher than the first temperature provided to a lower region flows.

[0008] In some examples, the first temperature may be between -200°C and 0°C, and the second temperature may be between 0°C and 80°C. In some examples, the base member can further include a thermal isolation cavity provided between the first flow path and the second flow path.

[0009] In some examples, the thermal blocking cavity may include a first thermal blocking cavity provided between the first flow path and the second flow path, and a second thermal blocking cavity provided between the first flow paths and connected to the first thermal blocking cavity.

[0010] In some examples, the thermal blocking cavity may include a first thermal blocking cavity provided between the first flow path and the second flow path, and a second thermal blocking cavity provided between the second flow path and connected to the first thermal blocking cavity.

[0011] In some examples, the thermal blocking cavity may include a first thermal blocking cavity provided between the first flow path and the second flow path, a second thermal blocking cavity provided between the first flow paths and connected to the first thermal blocking cavity, and a third thermal blocking cavity provided between the second flow paths and connected to the first thermal blocking cavity.

[0012] In some examples, the interior of the heat blocking cavity may be filled with a thermal insulating material. In some examples, the heat blocking cavity has a YSZ (Yttria-stabilized zirconia) coating on the upper or lower surface, a YSZ plate bonded thereto, or an Al 2 TiO 5 is coated or Al 2 TiO 5 The plates may be bonded.

[0013] In some examples, the base member can further include a thermal barrier heater provided between the first flow path and the second flow path. In some examples, the base member may further include: a thermal blocking cavity provided between the first flow path and the second flow path; and a thermal blocking heater provided between the first flow path and the second flow path.

[0014] In some examples, the device can further include a bonding layer interposed between the base member and the support member. In some examples, the bonding layer may include a silicone polymer family or a metal family.

[0015] In some examples, the bonding layer may include at least one of one-part silicone, two-part silicone, one-part epoxy, two-part epoxy, and polyurethane having a thermal conductivity between 0.3 W / mK and 3 W / mK.

[0016] In some examples, the bonding layer can include at least one of a ceramic filler and a metallic filler. In some examples, the bonding layer may include a metallized brazing layer, an active metal brazing layer, a diffusion bonded layer, a friction welded layer, or a laser welded layer between the base member and the support member. Effect of the Invention

[0017] The present disclosure provides a low-temperature electrostatic chuck that can be attached to equipment and prevents the formation of frost, ice, moisture, or the like on the equipment. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 2a] 1A-1D are cross-sectional views illustrating a method for manufacturing an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 2b] 1A-1D are cross-sectional views illustrating a method for manufacturing an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 2c] 1A-1D are cross-sectional views illustrating a method for manufacturing an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 2d] 1A-1D are cross-sectional views illustrating a method for manufacturing an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 3a] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 3b] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 4] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 5a] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 5b] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 5c] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 6] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 7] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 8a] 1A-1D are cross-sectional views illustrating a method for manufacturing an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 8b] 1A-1D are cross-sectional views illustrating a method for manufacturing an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 8c]1A-1D are cross-sectional views illustrating a method for manufacturing an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 9a] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 9b] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 10] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 11a] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 11b] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 11c] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. [Figure 12] FIG. 1 illustrates a cross-sectional view of an exemplary low-temperature electrostatic chuck in accordance with the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present disclosure is provided to more completely explain the present invention to those having ordinary skill in the art, and the following examples can be modified into many other forms, and the scope of the present invention is not limited to the following examples. Rather, these examples are provided to make the present disclosure more complete and complete, and to fully convey the idea of ​​the present invention to those skilled in the art.

[0020] In the following drawings, the thickness and size of each layer are exaggerated for convenience and clarity of description, and the same reference numerals in the drawings refer to the same elements. As used herein, the term "and / or" includes any one and all combinations of one or more of the listed items. In addition, in this specification, "connected" refers not only to the case where member A and member B are directly connected, but also to the case where member A and member B are indirectly connected with member C interposed between them.

[0021] The terms used in this specification are for describing specific embodiments and are not intended to limit the present invention. As used in this specification, the singular form can include the plural form unless the context clearly indicates otherwise. In addition, as used in this specification, "comprise", "include" and / or "comprising", "including" specify the presence of each mentioned shape, number, step, operation, member, element and / or group thereof, but do not exclude the presence or addition of one or more other shapes, numbers, operations, members, elements and / or groups thereof.

[0022] In this specification, terms such as "first" and "second" are used to describe various members, parts, regions, layers, and / or portions, but it is clear that these members, parts, regions, layers, and / or portions should not be limited by these terms. These terms are used only to distinguish one member, part, region, layer, or portion from another region, layer, or portion. Thus, a "first" member, part, region, layer, or portion described in detail below can be referred to as a "second" member, part, region, layer, or portion without departing from the teachings of the present invention.

[0023] Space-related terms such as "beneath," "below," "lower," "above," and "upper" may be used to facilitate understanding of one element or feature from another element or feature shown in the drawings. Such space-related terms are used to facilitate understanding of the present invention in various process or use states of the present invention, and are not intended to limit the present invention. For example, when an element or feature in the drawings is turned over, an element or feature described as "below" or "below" becomes "upper" or "above." Thus, "below" is a concept that encompasses "upper" or "below."

[0024] First, the coating type low-temperature electrostatic chuck will be described. 1 is a cross-sectional view of an exemplary low-temperature electrostatic chuck 100A in accordance with the present disclosure. In the example shown in FIG. 1, the exemplary low-temperature electrostatic chuck 100A in accordance with the present disclosure can include a base member 110 and a support member 120.

[0025] The base member 110 may include a lower region 111 and an upper region 112 provided on the lower region 111. In some examples, the upper region 112 may be provided with a number of first flow paths 113 having a predetermined pitch through which a first fluid at a first temperature flows, and the lower region 111 may be provided with a number of second flow paths 114 having a predetermined pitch through which a second fluid at a second temperature higher than the first temperature flows.

[0026] In some examples, the first temperature can be between about -200°C and about 0°C, and the second temperature can be between about 0°C and about 80°C. In some examples, the first and second fluids can include He, Ne, Ar, Kr, or Xe in liquid or gaseous state. The first and second fluids can differ from each other only in temperature and can be the same material, or can differ from each other in temperature and material.

[0027] Although the cross-sectional view of FIG. 1 shows multiple first and second flow channels 113, 114, in a substantially planar state, they may be provided in the form of one or multiple spirals or helices. In some examples, the base member 110 can further include an elongated thermal blocking cavity 115 provided between the first flow passage 113 and the second flow passage 114 .

[0028] In some examples, the heat blocking cavity 115 is hollow, which allows the first flow path 113 and the second flow path 114 to be blocked from heat exchange with each other. This allows the upper region 112 of the base member 110 to maintain a first temperature of the first flow path 113 (e.g., about -200°C to about 0°C), and the lower region 111 of the base member 110 to maintain a second temperature of the second flow path 114 (e.g., about 0°C to about 80°C).

[0029] In some examples, the thickness of the thermal blocking cavity 115 may be about 1% to about 30% of the thickness of the base member 110. If the thickness of the thermal blocking cavity 115 is less than about 1% of the thickness of the base member 110, the thermal blocking effect between the upper region 112 and the lower region 111 of the base member 110 may be small, while if the thickness of the thermal blocking cavity 115 is about 30% higher than the thickness of the base member 110, the thickness of the base member 110 may be relatively (unnecessarily) large. In some examples, the thermal blocking cavity 115 may be filled with a thermal insulating material (e.g., aerogel, perlite, foam glass, mineral wool, glass wool, etc.). In some examples, the upper surface and / or lower surface of the thermal blocking cavity 115 may be filled with a thermal insulating material such as YSZ (Yttria-stabilized zirconia) or Al, which has low thermal conductivity. 2 TiO 5 Coated or YSZ plate or Al 2 TiO 5 The plates may be bonded.

[0030] In some examples, the lower region 111 of the base member 110 may be directly or indirectly coupled to the equipment. As described above, even if the upper region 112 of the base member 110 is maintained at a low temperature of about -200°C to about 0°C, the lower region 111 of the base member 110 may be maintained at about 0°C to about 80°C (preferably at room temperature of about 1°C to 35°C), so that no frost, ice or moisture is formed in the attachment region of the etching equipment to which the low-temperature electrostatic chuck 100A is coupled. Therefore, defects in semiconductor wafers due to moisture during the semiconductor manufacturing process may be prevented.

[0031] In some examples, the base member 110 may be made of pure titanium, a titanium alloy, pure aluminum, or an aluminum alloy. For reference, pure titanium and / or a titanium alloy have a thermal expansion coefficient (unit: m / m° C.) of about 7×10 -6 to approximately 11×10 -6 while pure aluminum and / or aluminum alloys have a thermal expansion coefficient of 23×10 -6It could be.

[0032] The support member 120 may be provided directly on the base member 110 without a bonding layer. In some examples, the support member 120 may include a first dielectric layer 121, an electrode layer 123, and a second dielectric layer 122. The first dielectric layer 121 may be provided coated directly on the base member 110 without a bonding layer. The electrode layer 123 may be provided on the first dielectric layer 121. The second dielectric layer 122 may be provided coated directly on the first dielectric layer 121 and the electrode layer 123.

[0033] In some examples, the first dielectric layer 121 may be provided by being directly coated on the base member 110 using an atmospheric plasma spray method. In some examples, the second dielectric layer 122 may be provided by being directly coated on the electrode layer 123 and the first dielectric layer 121 using an atmospheric plasma spray method. In some examples, aerosol deposition, arc spray, high velocity oxygen-fuel spray, cold spray, or flame spray may be used in addition to the atmospheric plasma spray method.

[0034] In some examples, at least one of the first and second dielectric layers 121, 122 may be provided as a ceramic. In some examples, at least one of the first and second dielectric layers 121, 122 may be provided as a ceramic. 2 ), Beryllium oxide (BeO), Aluminum oxide (Al 2 O 3 ), aluminum nitride (AlN), silicon carbide (SiC), silicon nitride (Si 3 N 4 ) or aluminum titanate (Al 2 TiO 5 In some examples, at least one of the first and second dielectric layers 121, 122 may include yttrium oxide (Y 2 O 3 ), yttrium oxyfluoride (YOF) or yttrium fluoride (YF 3 ). For reference, the thermal expansion coefficient of zirconia is about 11×10 -6The thermal expansion coefficient of beryllium oxide is about 8×10 -6 The thermal expansion coefficient of aluminum oxide is about 7.3×10 -6 The thermal expansion coefficient of aluminum nitride is about 4.4×10 -6 The thermal expansion coefficient of silicon carbide is about 3.7 x 10 -6 The thermal expansion coefficient of silicon nitride is about 3.4×10 -6 The thermal expansion coefficient of aluminum titanate is about 1×10 -6 The thermal expansion coefficients of yttrium oxide, yttrium oxyfluoride, and yttrium fluoride are about 10 to about 10.5×10 -6 It is.

[0035] Therefore, by appropriately selecting materials for the base member 110 and the support member 120 having a small difference in thermal expansion coefficient therebetween, it is possible to minimize the warping phenomenon of the low-temperature electrostatic chuck 100A caused by the difference in thermal expansion coefficient therebetween.

[0036] In some examples, the base member 110 and / or the support member 120 may be provided in the form of a generally circular plate when viewed from above if it is intended for a semiconductor wafer, and in some examples, the base member 110 and / or the support member 120 may be provided in the form of a generally rectangular plate when viewed from above if it is intended for a display glass.

[0037] In some examples, when the low-temperature electrostatic chuck 100A is used for semiconductor manufacturing, the diameter of the support member 120 may be about 100 mm to about 400 mm. In some examples, when the low-temperature electrostatic chuck 100A is used for display manufacturing, the length of one side of the support member 120 may be about 400 mm to about 3500 mm.

[0038] In this manner, the present disclosure provides a low-temperature electrostatic chuck 100A that can be directly or indirectly mounted on an etching device, and further includes a thermal blocking cavity 115 between the upper and lower regions to prevent heat from being transferred from the upper region to the lower region and prevent frost, ice, moisture, etc. from being formed on the etching device.

[0039] 2a-2d are schematic diagrams illustrating a method for manufacturing an exemplary low-temperature electrostatic chuck 100A in accordance with the present disclosure. 2a illustrates an example low-temperature electrostatic chuck 100A in accordance with the present disclosure at an early stage in its manufacture. A base member 110 may be provided having an upper region 112 with multiple first flow passages 113 through which a first fluid flows at a first temperature, a lower region 111 with multiple second flow passages 114 through which a second fluid flows at a second temperature higher than the first temperature, and a thermal isolation cavity 115 between the first and second flow passages 113 and 114. In some examples, the base member 110 may be made of pure titanium, a titanium alloy, pure aluminum, or an aluminum alloy.

[0040] 2b is a diagram illustrating a later stage of manufacturing an exemplary low-temperature electrostatic chuck 100A according to the present disclosure. A first dielectric layer 121 may be directly coated on the base member 110. In some examples, aluminum oxide powder may be directly coated on the base member 110 by atmospheric plasma spraying. This allows the first dielectric layer 121 to be provided directly on the base member 110 without a bonding layer being present between the base member 110 and the first dielectric layer 121. Undescribed reference numeral 150 in the figure denotes a powder spray nozzle.

[0041] 2c illustrates a later stage of fabrication of an exemplary low-temperature electrostatic chuck 100A according to the present disclosure. An electrode layer 123 may be provided on the first dielectric layer 121. The electrode layer 123 may also be provided by a plating method or by various spraying methods as described above. The electrode layer 123 may include tungsten (W) and / or titanium (Ti).

[0042] 2d illustrates a later stage of manufacturing an exemplary low-temperature electrostatic chuck 100A according to the present disclosure. The second dielectric layer 122 may be directly coated on the first dielectric layer 121 and the electrode layer 123. In some examples, aluminum oxide powder may be coated on the first dielectric layer 121 and the electrode layer 123 by atmospheric plasma spraying. Here, the first dielectric layer 121, the electrode layer 123, and the second dielectric layer 122 may be defined or referred to as the support member 120.

[0043] 3a and 3b are cross-sectional views of other exemplary low-temperature electrostatic chucks 200A, 200B according to the present disclosure. In the example shown in FIG. 3a and FIG. 3b, another exemplary low-temperature electrostatic chuck 200A according to the present disclosure may include a thermal blocking heater 215. In some examples, the thermal blocking heater 215 may be provided between the first flow passage 113 and the second flow passage 114 in approximately parallel. In some examples, the thermal blocking heater 215 may include a nickel-chromium hot wire and an insulator covering the same. In the cross-sectional state of FIG. 3a and FIG. 3b, a number of thermal blocking heaters 215 are shown, but in a substantially planar state, the thermal blocking heaters 215 may be provided in the form of one or a number of spirals or helices. The thermal blocking heater 215 prevents the heat of the first flow passage 113 from being transferred to the second flow passage 114, and as a result, the temperature of the second flow passage 114 may be adjusted to a temperature similar to the temperature of the equipment (e.g., room temperature).

[0044] In some examples, the thermal blocking heater 215 may be provided in a position that does not correspond to (vertically offset from) the first flow path 113 and the second flow path 114 (see FIG. 3a), or in a position that corresponds to (vertically the same as) the first flow path 113 and the second flow path 114 (see FIG. 3b).

[0045] Meanwhile, in the low-temperature electrostatic chucks 200A and 200B according to the present disclosure, after the etching process of the semiconductor wafer is completed at a cryogenic temperature, the operation of the first flow passage 113 can be stopped and instead the temperature of the thermal blocking heater 215 can be further increased.

[0046] For example, by increasing the temperature of the thermal blocking heater 215 to about 50°C to about 100°C, the temperature of the semiconductor wafer can also reach the above temperature range, preventing moisture from remaining on the surface of the semiconductor wafer when it is removed from the process chamber.

[0047] FIG. 4 is a cross-sectional view of an exemplary low-temperature electrostatic chuck 300A according to the present disclosure. In the example shown in FIG. 4, another exemplary low-temperature electrostatic chuck 300A according to the present disclosure may further include a thermal blocking cavity 115 and a thermal blocking heater 215. In some examples, the thermal blocking cavity 115 and the thermal blocking heater 215 may be provided between the first flow passage 113 and the second flow passage 114 in approximately parallel relation. In some examples, the thermal blocking cavity 115 may be located at the top and the thermal blocking heater 215 may be located at the bottom, but vice versa is also possible. The thermal blocking cavity 115 and the thermal blocking heater 215 prevent the heat of the first flow passage 113 from being transferred to the second flow passage 114, so that the temperature of the second flow passage 114 can be adjusted to a temperature similar to that of the equipment. In addition, after the etching process is completed, the temperature of the semiconductor wafer can be quickly increased to room temperature using the thermal blocking heater 215.

[0048] TIFF2025508947000002.tif107170

[0049] TIFF2025508947000003.tif81170

[0050] 5c, the thermal blocking cavity 415 may include a first thermal blocking cavity 4151 provided between the first flow path 113 and the second flow path 114, a second thermal blocking cavity 4152 provided between the first flow path 113 and connected to the first thermal blocking cavity 4151, and a third thermal blocking cavity 4153 provided between the second flow path 114 and connected to the first thermal blocking cavity 4151. In some examples, the width of the first thermal blocking cavity 4151 may be greater than the widths of the second and third thermal blocking cavities 4152, 4153. In some examples, the thermal blocking cavity 415 may have a generally "+" cross-sectional shape.

[0051] FIG. 6 is a cross-sectional view of an exemplary low-temperature electrostatic chuck 500A in accordance with the present disclosure. As shown in FIG. 6 , in another exemplary low-temperature electrostatic chuck 500A according to the present disclosure, in particular, the base member 110 may include a thermal blocking cavity 415 provided between the first flow passage 113 and the second flow passage 114, and may further include an insulating material 510 having a thermal conductivity of less than about 10 provided in the thermal blocking cavity 415.

[0052] In some examples, the thermal insulation material 510 is YSZ (Yttria-stabilized zirconia) or Al coated on the thermal barrier cavity 415. 2 TiO 5 , or a YSZ plate or Al bonded to the thermal barrier cavity 415 2 TiO 5 The insulation material 510 may include a plate. In some examples, the insulation material 510 may have a thermal conductivity of about 0.1 W / mK to about 0.35 W / mK. In some examples, the insulation material 510 may have a height (thickness) smaller than the height (thickness) of the thermal barrier cavity 415, so that a substantial upper region and / or lower region of the thermal barrier cavity 415 may remain in the form of a cavity.

[0053] In some examples, the thermal blocking cavity 415 may include a first thermal blocking cavity 4151 extending between the first flow path 113 and the second flow path 114, a second thermal blocking cavity 4152 extending from the first thermal blocking cavity 4151 to the first flow path 113, and a third thermal blocking cavity 4153 extending from the first thermal blocking cavity 4151 to the second flow path 114. In some examples, the insulating material 510 may be located in the first thermal blocking cavity 4151 extending between the first flow path 113 and the second flow path 114.

[0054] In this manner, the present disclosure provides a structure in which the lower region 111 (relatively high temperature region) and the upper region 112 (relatively low temperature region) of the base member 110 are unlikely to exchange heat with each other, thereby preventing the formation of frost, ice, moisture, etc. on the equipment and providing a variety of low-temperature electrostatic chucks that can be attached to equipment.

[0055] Next, the bonding type low-temperature electrostatic chuck will be described, in which the description of the structure, material and / or function that overlaps with the coating type low-temperature electrostatic chuck will be minimized.

[0056] 7 is a cross-sectional view of an exemplary low-temperature electrostatic chuck 100B in accordance with the present disclosure. In the example shown in FIG. 7, the exemplary low-temperature electrostatic chuck 100B in accordance with the present disclosure can include a base member 110, a support member 120, and a bonding layer 130.

[0057] The bonding layer 130 may be interposed between the base member 110 and the support member 120. In some examples, the bonding layer 130 may include a silicone polymer-based or metal-based bonding layer. In some examples, the silicone polymer-based bonding layer may enable the electrostatic chuck to be used at a temperature range of about -200°C to about 0°C, and the metal-based bonding layer may enable the electrostatic chuck to be used at a temperature range of about 0°C to about 80°C.

[0058] In some examples, the silicone polymer based bonding layer can include at least one of a one-part silicone, a two-part silicone, a one-part epoxy, a two-part epoxy, and a polyurethane having a thermal conductivity of about 0.3 W / mK to about 3 W / mK.

[0059] In some examples, one-part silicone (or one-part epoxy) begins to harden when it reacts with moisture in the air, so if it is stored in a container that prevents contact with air and applied to the base member 110, the hardening will gradually diffuse from the surface to the inside. In some examples, two-part silicone (or two-part epoxy) hardens as the two parts (curing agent and base) are mixed on the base member 110, regardless of moisture in the air. In some examples, the polyurethane adhesive may also contain one-part polyurethane or two-part polyurethane.

[0060] In some examples, the bonding layer 130 may further include a nano-filler, such as a ceramic filler or a metal filler, to improve thermal conductivity. In some examples, the average size of the nano-filler may be about 1 nm to about 10 μm. In some examples, the weight (wt%) of the nano-filler may be about 5 wt% to about 95 wt%. If the weight of the nano-filler is less than about 5 wt%, the thermal conductivity may be lower than the target value. If the weight of the nano-filler is more than about 95%, the viscosity may be relatively high, making it difficult to spray / apply the adhesive. In some examples, the thickness of the bonding layer 130 may be about 1 μm to about 100 mm. If the thickness of the bonding layer 130 is less than about 1 μm, the thermal conductivity is excellent, but the thermal diffusion performance is reduced, so the thermal uniformity of the support member 120 may be reduced. If the thickness of the bonding layer 130 is greater than about 100 mm, the thermal uniformity of the support member 120 may be high due to excellent thermal diffusion performance, but the thermal conductivity may be low.

[0061] In some examples, the nano-fillers can include pure titanium (CTE: 8.6), beryllium oxide (CTE: 8), and / or aluminum oxide (CTE: 7.3). In some examples, the nano-fillers can include a material (metal or ceramic) similar to or the same as the base member 110 and / or the support member 120.

[0062] In some examples, the metallurgical bonding layer 130 may include a metallized brazing layer, an active metal brazing layer, a diffusion bonding layer, a friction welding layer, and / or a laser welding layer between the base member (i.e., metal) 110 and the support member (i.e., ceramic) 120. Alternatively, glass frit bonding, metal brazing bonding, diffusion bonding, and / or diffusion brazing bonding may be used.

[0063] As an example, the metallized brazing layer can be provided by forming a metal layer on the ceramic surface and then bonding using a brazing alloy. Methods for forming the metal layer include a method of applying an intermetallic compound, precipitating the metal by thermal decomposition, and reacting with the ceramic, a method of precipitating the metal in the gas phase, and a method of plating using a physical method such as deposition or sputtering. As an example, the Mo-Mn method can be used. In this method, Mo or Mo-Mn powder is mixed with a binder in an organic solvent to form a paste, which is then applied to the ceramic, metallized, and brazed. As an example, Ti can be metallized and stabilized zirconia (PSZ) and Ti-6Al-4V can be bonded at about 820°C. As an example, the zirconia surface can be metallized with Ti and then bonded using an Ag-28Cu-based brazing alloy. In some examples, a Ti-O compound (TiO, Ti) is applied to the surface of the metallized zirconia. 2 O 3 , Ti 3 O 5 , TiO 2 A black reaction layer made of a black fluorine-containing compound (e.g., fluorine-containing ...) is provided, which improves the wettability of the ceramic surface and realizes good bonding.

[0064] For example, active metal brazing layers are not only reliable and economical for manufacturing small products, but also suitable for mass production processes where products with complex shapes must be joined in one operation. An alloy in which an appropriate amount of Group IV active metals such as Ti and Zr are added to soft metals such as Ni, Cu, and Ag is used as a brazing alloy, and direct joining is performed in a vacuum or inert atmosphere. The active metals such as Ti and Zr contained in the brazing alloy react with the ceramic to form oxides, nitrides, or carbides at the interface, thereby achieving joining. In addition, Ag, Cu, etc. are segregated in the center to form a soft layer, which has a stress relaxation effect, improving the joining strength.

[0065] In some cases, the diffusion bonding layer is a layer obtained by bonding two materials together and using the diffusion of atoms that occurs between the bonding surfaces. It is characterized by little thermal stress or deformation after bonding and little deterioration of materials due to structural changes, and is capable of bonding not only homogeneous materials but also dissimilar materials with different properties and complex shapes. There are two methods for bonding: one is to pressurize and heat the metal under a stress that barely deforms it, and the other is to pressurize and heat the metal so that it deforms. Bonding is performed through a three-step process: plastic deformation due to high-temperature creep, disappearance of voids due to the diffusion of each atom, and grain boundary migration. In the diffusion bonding method, important factors for bonding include vacuum atmosphere control, heating and maintaining the temperature of the bonding materials, and reducing the thermal stress that occurs when the temperature rises and falls.

[0066] In some examples, the friction weld layer can be obtained by rotating the metal and ceramic while applying pressure, heating them with the frictional heat, and then applying pressure to bond them together when they reach a certain temperature. In some cases, the laser beam welded layer is a layer obtained by using high-density energy as a heat source, and high-power lasers include CO2 lasers and Nd:YAG lasers. Although lasers are thermal processes, they have a small beam and a high energy density (10 6 W / cm 2As a result, the effect of heat is small, welding can be performed within a small deformation range, and fine welding is possible due to the good controllability of the input energy.

[0067] In this manner, the present disclosure can provide a low-temperature electrostatic chuck 100B in which the distance between the first flow passage 113 in the base member 110 and the support member 120 is relatively increased by interposing a bonding layer 130 having high thermal conductivity between the base member 110 and the support member 120, thereby achieving high temperature uniformity on the support member 120.

[0068] In some examples, the electrostatic chuck may be used in a temperature range of about −200° C. to about 0° C. In some examples, the standard deviation of the thermal expansion coefficients between the base member 110, the support member 120, and the bonding layer 130 may be about 0.01% to about 10%. Thus, in the range of about −200° C. to about 0° C., which is the operating temperature of the electrostatic chuck, the warping phenomenon caused by the difference in the thermal expansion coefficients between the base member 110, the support member 120, and the bonding layer 130 may be minimized, and as a result, the flatness of the electrostatic chuck may be excellently maintained in a low-temperature environment.

[0069] In some examples, when the base member 110 is made of pure titanium (CTE: 8.6), the first and second dielectric layers 121, 122 constituting the support member 120 are made of beryllium oxide (CTE: 8), and the bonding layer 130 is made of pure titanium (CTE: 8.6) or beryllium oxide (CTE: 8), the standard deviation of the CTE may be about 0.4%. In some examples, when the base member 110 is made of pure titanium (CTE: 8.6), the first and second dielectric layers 121, 122 constituting the support member 120 are made of aluminum oxide (CTE: 7.3), and the bonding layer 130 is made of aluminum oxide (CTE: 7.3), the standard deviation of the CTE may be about 0.9%.

[0070] 8a-8c are schematic diagrams illustrating a method for manufacturing an exemplary low-temperature electrostatic chuck 100B in accordance with the present disclosure. 8a illustrates an example low-temperature electrostatic chuck 100B in accordance with the present disclosure at an early stage in its manufacture. A base member 110 may be provided having an upper region 112 with multiple first flow passages 113 through which a first fluid flows at a first temperature, a lower region 111 with multiple second flow passages 114 through which a second fluid flows at a second temperature higher than the first temperature, and a thermal isolation cavity 115 between the first and second flow passages 113 and 114. In some examples, the base member 110 may be made of pure titanium, a titanium alloy, or aluminum.

[0071] 8b illustrates a later stage in the manufacture of an exemplary low-temperature electrostatic chuck 100B in accordance with the present disclosure. A bonding layer 130 may be provided on the base member 110. In some examples, the bonding layer 130 may be provided on the base member 110 via a dispenser, sprayer, jetting device, 3D printer, or the like. The bonding layer 130 may be provided on the entire top surface of the base member 110 or may be provided in a dot array form on the entire top surface.

[0072] 8c illustrates a later stage of manufacturing an exemplary low-temperature electrostatic chuck 100B according to the present disclosure. A support member 120 including a first dielectric layer 121, a second dielectric layer 122, and an electrode layer 123 may be attached to the bonding layer 130. In some examples, the first dielectric layer 121 may be provided as aluminum oxide. In some examples, the first dielectric layer 121 may be provided in a plate form through a sintering process. In some examples, the electrode layer 123 may be provided on the first dielectric layer 121. The electrode layer 123 may be provided by a plating method or various spraying methods. The electrode layer 123 may include tungsten (W) and / or titanium (Ti). In some examples, the second dielectric layer 122 may be directly coated on the first dielectric layer 121 and the electrode layer 123. In some examples, aluminum oxide powder may be coated on the first dielectric layer 121 and the electrode layer 123 by atmospheric plasma spraying.

[0073] In this way, the base member 110 contains titanium, and the support member 120 and the bonding layer 130 contain aluminum oxide, so that the standard deviation of the thermal expansion coefficients of the base member 110, the support member 120 and the bonding layer 130 is less than about 2%, and as a result, even if the electrostatic chuck is used in a low-temperature environment of about -200°C to about 0°C, the base member 110, the support member 120 and the bonding layer 130 are hardly warped and maintain excellent flatness. Therefore, the fixing force of the glass or wafer by the electrostatic chuck can be maintained excellently.

[0074] 9a and 9b are cross-sectional views of other exemplary low-temperature electrostatic chucks 200C, 200D according to the present disclosure. 9a and 9b, another exemplary low-temperature electrostatic chuck 200C, 200D according to the present disclosure may include a thermal blocking heater 215. In some examples, the thermal blocking heater 215 may be provided substantially parallel between the first flow passage 113 and the second flow passage 114. In some examples, the thermal blocking heater 215 may be made of a nickel-chromium hot wire and an insulator covering the hot wire. The thermal blocking heater 215 prevents the heat of the first flow passage 113 from being transferred to the second flow passage 114, so that the temperature of the second flow passage 114 can be adjusted to a temperature similar to the temperature of the equipment (e.g., room temperature).

[0075] In some examples, the thermal blocking heater 215 may be provided at a position not corresponding to the first flow path 113 and the second flow path 114 (see FIG. 9a), or at a position corresponding to the first flow path 113 and the second flow path 114 (see FIG. 9b).

[0076] FIG. 10 is a cross-sectional view of an exemplary low-temperature electrostatic chuck 300B in accordance with the present disclosure. 10, another exemplary low-temperature electrostatic chuck 300B according to the present disclosure may further include a thermal blocking cavity 115 and a thermal blocking heater 215. In some examples, the thermal blocking cavity 115 and the thermal blocking heater 215 may be provided in parallel between the first flow passage 113 and the second flow passage 114. In some examples, the thermal blocking cavity 115 may be located at the top and the thermal blocking heater 215 may be located at the bottom, although vice versa is also possible.

[0077] 11a-11c are cross-sectional views of exemplary low-temperature electrostatic chucks 400D, 400E, and 400F according to the present disclosure. In some examples, such as the electrostatic chuck 400D shown in FIG. 11a, the thermal blocking cavity 415 may include a first thermal blocking cavity 4151 provided between the first flow path 113 and the second flow path 114, and a second thermal blocking cavity 4152 provided between the first flow path 113 and connected to the first thermal blocking cavity 4151.

[0078] In some examples, such as the electrostatic chuck 400E shown in FIG. 11b, the thermal blocking cavity 415 may include a first thermal blocking cavity 4151 provided between the first flow path 113 and the second flow path 114, and a second thermal blocking cavity 4152 provided between the second flow path 114 and connected to the first thermal blocking cavity 4151.

[0079] In some examples, such as the electrostatic chuck 400F shown in FIG. 11c, the thermal blocking cavity 415 may include a first thermal blocking cavity 4151 provided between the first flow path 113 and the second flow path 114, a second thermal blocking cavity 4152 provided between the first flow path 113 and connected to the first thermal blocking cavity 4151, and a third thermal blocking cavity 4153 provided between the second flow path 114 and connected to the first thermal blocking cavity 4151.

[0080] FIG. 12 is a cross-sectional view of an exemplary low-temperature electrostatic chuck 500B in accordance with the present disclosure. As shown in FIG. 12 , in another exemplary low-temperature electrostatic chuck 500B according to the present disclosure, in particular, the base member 110 may include a thermal blocking cavity 415 provided between the first flow passage 113 and the second flow passage 114, and may include an insulating material 510 having a thermal conductivity of less than about 10 provided in the thermal blocking cavity 415.

[0081] In some examples, the thermal insulation material 510 is YSZ (Yttria-stabilized zirconia) or Al coated on the thermal barrier cavity 415. 2 TiO 5 , or a YSZ plate or Al bonded to the thermal barrier cavity 415 2 TiO 5 It may include a plate.

[0082] In some examples, the insulation material 510 may be located in a first thermal blocking cavity 4151 extending between the first flow path 113 and the second flow path 114, and additionally, the thermal blocking cavity 415 may further include a second thermal blocking cavity 4152 extending from the first thermal blocking cavity 4151 to the first flow path 113, and a third thermal blocking cavity 4153 extending from the first thermal blocking cavity 4151 to the second flow path 114.

[0083] What has been described above is merely one embodiment for implementing an exemplary low-temperature electrostatic chuck according to the present disclosure, and the present invention is not limited to the above embodiment. As claimed in the following claims, it can be said that anyone having ordinary knowledge in the field to which the invention pertains can implement various modifications without departing from the gist of the present invention, to the extent that they encompass the technical spirit of the present invention.

Claims

1. A base member; and a support member comprising a first dielectric layer coated on said base member, an electrode layer provided on said first dielectric layer, and a second dielectric layer coated on said first dielectric layer and said electrode layer; The base member includes a first flow passage through which a first fluid having a first temperature is provided to an upper region, and a second flow passage through which a second fluid having a second temperature, higher than the first temperature, is provided to a lower region.

2. 2. The low temperature electrostatic chuck of claim 1, wherein said first temperature is between -200°C and 0°C and said second temperature is between 0°C and 80°C.

3. The low temperature electrostatic chuck of claim 1 , wherein the base member further includes a thermal isolation cavity provided between the first and second flow passages.

4. 4. The low-temperature electrostatic chuck of claim 3, wherein the thermal blocking cavity includes: a first thermal blocking cavity provided between the first flow passage and the second flow passage; and a second thermal blocking cavity provided between the first flow passage and coupled to the first thermal blocking cavity.

5. 4. The low-temperature electrostatic chuck of claim 3, wherein the thermal blocking cavity includes a first thermal blocking cavity provided between the first flow passage and the second flow passage, and a second thermal blocking cavity provided between the second flow passage and coupled to the first thermal blocking cavity.

6. 4. The low-temperature electrostatic chuck of claim 3, wherein the thermal blocking cavity includes: a first thermal blocking cavity provided between the first flow passage and the second flow passage; a second thermal blocking cavity provided between the first flow passage and connected to the first thermal blocking cavity; and a third thermal blocking cavity provided between the second flow passage and connected to the first thermal blocking cavity.

7. 4. The low-temperature electrostatic chuck of claim 3, wherein the interior of said heat blocking cavity is filled with a heat insulating material.

8. The heat insulating cavity is coated with YSZ (Yttrium-stabilized zirconia) on the upper or lower surface, or a YSZ plate is bonded to the cavity, or an Al ２ TiO ５ is coated or Al ２ TiO ５ 4. The low temperature electrostatic chuck of claim 3, wherein the plates are bonded together.

9. 2. The low temperature electrostatic chuck of claim 1, wherein the base member further comprises a thermal barrier heater provided between the first flow passage and the second flow passage.

10. The base member is a thermal isolation cavity provided between the first flow path and the second flow path; and 10. The low temperature electrostatic chuck of claim 1, further comprising: a thermal barrier heater provided between said first flow path and said second flow path.

11. 10. The low temperature electrostatic chuck of claim 1 further comprising a bonding layer interposed between said base member and said support member.

12. 12. The low temperature electrostatic chuck of claim 11, wherein the bonding layer comprises a silicone polymer family or a metal family.

13. 12. The low temperature electrostatic chuck of claim 11, wherein the bonding layer comprises at least one of one-part silicone, two-part silicone, one-part epoxy, two-part epoxy, and polyurethane having a thermal conductivity between 0.3 W / mK and 3 W / mK.

14. 12. The low temperature electrostatic chuck of claim 11, wherein the bonding layer comprises at least one of a ceramic filler and a metallic filler.

15. 12. The low temperature electrostatic chuck of claim 11, wherein the bonding layer comprises a metallized brazing layer, an active metal brazing layer, a diffusion bonded layer, a friction welded layer, or a laser welded layer between the base member and the support member.

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