Wafer-supporting edge ring

Abstract

The present invention provides a wafer-supporting edge ring comprising: a first edge ring positioned outside a wafer to support the outer periphery of the wafer; and a second edge ring positioned outside the first edge ring to support the outer periphery of the first edge ring. According to the present invention, the wafer-supporting edge ring is formed of multiple separate segments, and can thus prevent thermal shock damage caused by the temperature difference between the inner and outer peripheries thereof. Furthermore, the wafer-supporting edge ring comprises: the first edge ring positioned at an inner side to support a wafer; and the second edge ring positioned at an outer side to support the first edge ring, whereby heat transfer from the wafer can be blocked, and the temperature difference at the outer periphery of the wafer can be reduced.

Description

Wafer support edge ring

[0001] The present invention relates to an edge ring that supports a wafer in a process chamber for semiconductor manufacturing.

[0002] A process chamber for semiconductor manufacturing can perform semiconductor processes, such as heat treatment, while supporting a wafer using edge rings in its internal space. Additionally, the heat treatment process may include processes such as heat treatment of various thin films deposited on the semiconductor wafer, ion implantation, and activation. The heat treatment process may utilize a Rapid Thermal Process (RTP) that performs heat treatment at 1,000 to 1,200°C for several seconds using a halogen lamp. Furthermore, to reduce the heat treatment time to the range of msec to usec, the heat treatment process may utilize a Xe-flash lamp and employ methods such as Flash Lamp Annealing (FLA) or Laser Spike Annealing (LSA), which irradiate in the range of μsec to msec.

[0003] The above heat treatment process requires small temperature deviations and high temperature uniformity due to the miniaturization of semiconductor technology. The wafer can generally be heat-treated while its outer periphery is supported by an edge ring. Since heat is conducted and released from the outer periphery to the edge ring, the temperature of the outer periphery becomes relatively lower, which can cause a temperature difference between the center and the outer periphery. Therefore, it is necessary to reduce the temperature difference between the center and the outer periphery of the wafer during the heat treatment process. Additionally, the edge ring may be damaged by thermal shock due to the temperature difference occurring between the inner and outer peripheries.

[0004] The present invention aims to provide a wafer support edge ring that is separated into multiple parts to prevent thermal shock damage caused by temperature differences between the inner and outer parts.

[0005] In addition, the present invention aims to provide a wafer support edge ring that reduces the temperature variation of the wafer during a heat treatment process.

[0006] The wafer support edge ring of the present invention is characterized by comprising a first edge ring located on the outer side of a wafer to support the outer periphery of the wafer, and a second edge ring located on the outer side of the first edge ring to support the outer periphery of the first edge ring.

[0007] In addition, the first edge ring and the second edge ring may be formed from any one of silicon carbide (SiC), quartz, and graphite.

[0008] In addition, the first edge ring and the second edge ring may be formed of different materials.

[0009] In addition, the first edge ring may be formed of a material having a lower thermal conductivity than the second edge ring.

[0010] In addition, the first edge ring may be formed of sintered SiC, and the second edge ring may be formed of CVD-SiC.

[0011] Additionally, the first edge ring may include a first main body ring formed in a ring shape having a predetermined width and thickness, a first seating ring having a first seating area formed in a stepped shape extending downward from the upper surface of the first main body ring to be seated on the outer periphery of the wafer, and a first support ring having a predetermined thickness, with its upper end coupled to the outer periphery of the first main body ring and extending to a predetermined height in the downward direction; and the second edge ring may include a second main body ring formed in a ring shape having a predetermined width and thickness, a second seating ring having a second seating area formed in a stepped shape extending downward from the upper surface of the second main body ring to be seated on the first support ring of the first edge ring, and a second support ring having a predetermined thickness, with its upper end coupled to the outer periphery of the second main body ring and extending to a predetermined height in the downward direction.

[0012] Additionally, the first seating ring may include a first seating inclined ring, the upper end of which is coupled to the inner end of the first main body ring and extends to a predetermined height in a downward direction, and a first seating horizontal ring, the outer end of which is coupled to the lower end of the first seating inclined ring and extends horizontally inward to form the first seating area, and the second seating ring may include a second seating inclined ring, the upper end of which is coupled to the inner end of the second main body ring and extends to a predetermined height in a downward direction, and a second seating horizontal ring, the outer end of which is coupled to the lower end of the second seating inclined ring and extends horizontally inward to form the second seating area.

[0013] In addition, the thickness of the second seating area may be thinner than the thickness of the second main body ring.

[0014] In addition, the second main body ring may further include a second blocking groove in the shape of a groove that extends from the lower surface to the upper surface and forms a ring shape.

[0015] In addition, the second seating ring may further include a second stop ring that is ring-shaped and is formed to protrude along the inner circumference of the second seating area from the upper surface of the second seating ring.

[0016] Additionally, the first edge ring may include a first main body ring formed in a ring shape having a predetermined width and thickness, a first seating ring having a first seating area formed in a stepped shape extending downward from the upper surface of the first main body ring to be seated on the outer periphery of the wafer, and a first support ring having an upper end coupled to the outer periphery of the first main body ring, extending downward, and formed at a height smaller than the thickness of the first main body ring; and the second edge ring may include a second main body ring formed in a ring shape having a predetermined width and thickness, a second seating ring having a second seating area formed in a stepped shape extending downward from the upper surface of the second main body ring to be seated on the first support ring, and a second support groove extending upward from the outer lower surface of the second main body ring and formed as a ring-shaped groove along the lower surface.

[0017] In addition, the second main body ring may further include a second blocking groove in the shape of a groove that extends from the lower surface to the upper surface and forms a ring shape.

[0018] Since the wafer support edge ring of the present invention is formed by separating it into multiple parts, it can prevent thermal shock damage caused by the temperature difference between the inner and outer parts.

[0019] In addition, the wafer support edge ring of the present invention comprises a first edge ring located on the inner side to support the wafer and a second edge ring located on the outer side to support the first edge ring, thereby blocking heat transfer of the wafer and reducing the temperature difference on the outer periphery of the wafer.

[0020] In addition, the wafer support edge ring of the present invention can efficiently reduce the temperature variation of the wafer because the second edge ring is formed of a different material from the first edge ring, thereby relatively reducing heat transfer.

[0021] In addition, the wafer support edge ring of the present invention may have a blocking groove to reduce heat transfer from the second edge ring, thereby reducing the heat transferred to the second edge ring.

[0022] In addition, the wafer support edge ring of the present invention can reduce the heat transferred to the second edge ring by relatively reducing the thickness of the second seating area where the first edge ring is seated in the second edge ring.

[0023] In addition, the wafer support edge ring of the present invention can reduce the contact area between the second edge ring and the first edge ring, thereby reducing the heat transferred from the first edge ring to the second edge ring.

[0024] FIG. 1 is a vertical cross-sectional view of a substrate heat treatment device equipped with an edge ring for wafer support according to one embodiment of the present invention.

[0025] FIG. 2 is a vertical cross-sectional view of an edge ring for wafer support according to one embodiment of the present invention.

[0026] FIG. 3 is a vertical cross-sectional view of an edge ring for wafer support according to another embodiment of the present invention.

[0027] FIG. 4 is a vertical cross-sectional view of an edge ring for wafer support according to another embodiment of the present invention.

[0028] Figure 5 shows the measurement results for the temperature distribution of the wafer according to the embodiments of the present invention.

[0029] Figure 6 is a simulation result of the temperature distribution of the edge ring according to an embodiment of the present invention.

[0030] Figure 7 is the result of measuring the change in average temperature over time of the wafer and edge ring in Example 2 of the present invention.

[0031] The wafer support edge ring according to an embodiment of the present invention will be described in more detail below through the examples and the attached drawings.

[0032]

[0033] First, the structure of an edge ring for wafer support according to one embodiment of the present invention will be described.

[0034] FIG. 1 is a vertical cross-sectional view of a substrate heat treatment device equipped with a wafer support edge ring according to one embodiment of the present invention. FIG. 2 is a vertical cross-sectional view of a wafer support edge ring according to one embodiment of the present invention.

[0035]

[0036] A wafer support edge ring (100) according to one embodiment of the present invention may include a first edge ring (110) and a second edge ring (120), with reference to FIGS. 1 and 2. Additionally, the wafer support edge ring (100) may additionally include at least one edge ring having a structure similar to the first edge ring (110) inside the first edge ring (110). Additionally, the wafer support edge ring (100) may additionally include at least one edge ring having a structure similar to the first edge ring (110) or the second edge ring (120) between the first edge ring (110) and the second edge ring (120). The wafer support edge ring (100) may additionally include at least one edge ring having a structure similar to the second edge ring (120) on the outer side of the second edge ring (120). Accordingly, the wafer support edge ring (100) may be formed with a plurality of edge rings including the first edge ring (110) and the second edge ring (120). The wafer support edge ring (100) may be mounted inside a substrate heat treatment device in which a heat treatment process of the wafer (a) is performed to support the wafer (a).

[0037] Additionally, the wafer support edge ring (100) is formed such that the contact surfaces of the first edge ring (110) and the second edge ring (120) can accommodate the portions of variation caused by thermal expansion or thermal contraction when thermal expansion or thermal contraction occurs, thereby preventing the first edge ring (110) and the second edge ring (120) from being damaged by thermal shock. That is, the wafer support edge ring (100) may include a tolerance for thermal expansion or thermal contraction between the first edge ring (110) and the second edge ring (120).

[0038] The above substrate heat treatment device may be a general heat treatment device used in the heat treatment process of a wafer (a) in a semiconductor manufacturing process. For example, the above substrate heat treatment device (10) may be equipped with a process chamber (20), a beam irradiation module (30), and a substrate rotation module (40), as shown in FIG. 1. Additionally, the above substrate heat treatment device (10) may further include a gas injection module for injecting process gas, although not specifically illustrated.

[0039] The above substrate heat treatment device (10) can perform manufacturing processes such as an epitaxial process, a crystallization process, an ion implantation process, or an activation process on a wafer (a). The above substrate heat treatment device (10) can heat the wafer (a) by irradiating it with a laser beam generated from a beam irradiation module (30).

[0040] The process chamber (20) may provide an internal space in which a wafer (a) is received and heat-treated. The process chamber (20) may include an outer housing (21), an inner housing (22), a beam irradiation plate (23), and a rotating support (24). The outer housing (21), the inner housing (22), and the beam irradiation plate (23) may form an internal space in which the wafer (a) is located. Additionally, the beam irradiation plate (23) may be located below the wafer (a) and allow a laser beam irradiated from the beam irradiation module (30) to be transmitted and irradiated to the bottom of the wafer (a). Meanwhile, the beam irradiation plate (23) may be located above the wafer (a) depending on the position of the beam irradiation module (30). The beam irradiation plate (23) may be formed of a transparent plate through which the laser beam is transmitted, such as quartz or glass. The above-mentioned rotating support (24) can support the wafer support edge ring (100) and the wafer (a) on the inside. Additionally, the wafer (a) and the wafer support edge ring (100) can be rotated by the above-mentioned substrate rotation module (40). Meanwhile, when the above-mentioned beam irradiation module (30) rotates, the rotating support (24) and the wafer (a) may not rotate.

[0041] The beam irradiation module (30) may be located at the bottom of the beam irradiation plate (23) inside the inner housing (22). The beam irradiation module (30) may irradiate a laser beam onto the lower surface of the wafer (a) through the beam irradiation plate (23) from outside the process chamber (20). The beam irradiation module (30) may include a VCSEL element that generates a laser beam. Additionally, the beam irradiation module (30) may include a halogen lamp instead of the VCSEL element. Meanwhile, the beam irradiation module (30) may be located on the upper surface of the wafer (a) from outside the process chamber (20). In this case, the beam irradiation plate (23) may be coupled to the outer housing (21) on the upper surface of the wafer (a).

[0042] The substrate rotation module (40) may include an inner rotation means (41) and an outer rotation means (42). The substrate rotation module (40) can rotate the rotation support (24) in a non-contact manner in a horizontal direction. More specifically, the inner rotation means (41) may be coupled to the lower part of the rotation support (24) in the chamber lower space of the process chamber (20). The inner rotation means (41) may be formed with a structure similar to a motor rotor. Additionally, the outer rotation means (42) may be located on the outside of the process chamber (20) opposite the inner rotation means (41). The outer rotation means (42) may rotate the inner rotation means (41) non-contact using magnetic force. The outer rotation means (42) may be formed with a structure similar to a motor stator.

[0043] The wafer support edge ring (100) is positioned between the rotating support (24) and the wafer (a), is supported by the rotating support (24), and can support the outer side of the wafer (a) located on the inside. More specifically, the wafer support edge ring (100) may be formed to include a first edge ring (110) that supports the outer periphery of the wafer (a) and a second edge ring (120) that supports the outer periphery of the first edge ring (110). Additionally, the outer periphery of the second edge ring (120) may be supported by a substrate support. The rotating support (24) is formed in a ring shape overall, and a rotating mounting ring on which the wafer support edge ring (100) is seated may be formed on the inside. Additionally, a rotating protrusion ring may be formed on the upper surface of the rotating mounting ring of the rotating support (24). The above-mentioned rotating protrusion ring is formed in a ring shape along the inner circumference on the upper surface of the rotating seating ring, and can prevent the wafer support edge ring (100) from coming off.

[0044] The wafer support edge ring (100) of the present invention is formed by dividing it into an edge ring including a first edge ring (110) and a second edge ring (120), so thermal shock damage caused by a difference in internal temperature distribution compared to an edge ring formed as a whole can be prevented.

[0045] The wafer support edge ring (100) may have a first edge ring (110) and a second edge ring (120) formed from any one material selected from silicon carbide (SiC), quartz, and graphite. The first edge ring (110) and the second edge ring (120) may be formed from the same material or a different material selected from silicon carbide (SiC), quartz, and graphite.

[0046] In addition, the wafer support edge ring (100) of the present invention is formed by dividing into a first edge ring (110) and a second edge ring (120) that supports the first edge ring (110) on the outside of the first edge ring (110), so that heat transfer of the wafer (a) can be blocked and the temperature difference with respect to the outer periphery of the wafer (a) can be reduced.

[0047] The first edge ring (110) and the second edge ring (120) may preferably be formed of materials having different heat transfer characteristics to reduce the temperature variation on the outer periphery of the wafer (a). The first edge ring (110) may be formed of a material having a lower thermal conductivity than the second edge ring (120). Additionally, the first edge ring (110) may be formed of a material having a higher specific heat than the second edge ring (120). For example, the first edge ring (110) may be formed of sintered SiC, and the second edge ring (120) may be formed of CVD-SiC. Here, the sintered CVD may refer to SiC manufactured by sintering a powder containing SiC powder with a particle size at the micro level. The above CVD-SiC may refer to high-purity SiC obtained by depositing SiC onto graphite using CVD (chemical vapor deposition) and then removing the graphite.

[0048] In addition, in the following description, the inner side, inner end, inner surface, or inner circumference refers to the direction, end, or end surface in which the wafer (a) is located for each component, and the outer side, outer end, inner surface, or outer circumference may refer to the direction, end, or end surface opposite to the direction in which the wafer (a) is located.

[0049]

[0050] The first edge ring (110) may include a first body ring (111), a first seating ring (112), and a first support ring (113). The first edge ring (110) may be formed in a ring shape overall. The first edge ring (110) may be located on the outer periphery of a wafer (a) to support the wafer (a). The first edge ring (110) may be formed integrally with the first body ring (111), the first seating ring (112), and the first support ring (113). That is, the first edge ring (110) may be formed to include the first body ring (111), the first seating ring (112), and the first support ring (113) by processing a ring having a predetermined thickness and width.

[0051] As described above, the first edge ring (110) may be formed of a material having a lower thermal conductivity than the second edge ring (120). The first edge ring (110) may be formed of sintered SiC. The first edge ring (110) may have a thermal conductivity of 120 to 240 W / mK. The first edge ring (110) may have a specific heat of 750 to 810 J / kgK.

[0052] The first edge ring (110) may be formed with a thickness of 0.3 to 0.6 mm overall. The first edge ring (110) may be formed with a thickness smaller than that of the second edge ring (120).

[0053] The first main body ring (111) may be formed in a ring shape having a predetermined width and thickness. The first main body ring (111) may be formed with an appropriate width and outer diameter to have the strength required to support the wafer (a) located inside. The first main body ring (111) may be formed in a ring shape where the width is greater than the thickness. The first main body ring (111) may be formed with a thickness of 0.3 to 0.6 mm. The inner diameter of the first main body ring (111) may be formed to be larger than the outer diameter of the wafer (a).

[0054] The first mounting ring (112) may be formed in an "L" shape. More specifically, the first mounting ring (112) may include a first mounting inclined ring (112a) and a first mounting horizontal ring (112b). The first mounting ring (112) may be formed in a stepped shape extending downward from the upper surface of the first main body ring (111) to provide a first mounting area (112c) on which the outer periphery of the wafer (a) is mounted. The first mounting ring (112) is coupled to the inner side of the first main body ring (111) and can support the wafer (a) located on the inner side. That is, the first mounting ring (112) can support the outer periphery of the wafer (a) mounted in the mounting area. More specifically, the first mounting ring (112) can support the lower surface of the outer periphery of the wafer (a). The upper end of the first mounting ring (112) may be coupled to the inner end of the first main body ring (111) and may be located lower than the first main body ring (111). That is, the upper end of the first mounting inclined ring (112a) of the first mounting ring (112) may be coupled to the inner end of the first main body ring (111), and the outer end of the first mounting horizontal ring (112b) may be coupled to the lower end of the first mounting inclined ring (112a). The first mounting ring (112) may be formed with the same thickness as the first main body ring (111). In addition, the first mounting ring (112) may be formed with a thicker thickness than the first main body ring (111) to stably support the wafer (a).

[0055] The first mounting inclined ring (112a) has a predetermined thickness, and its upper end is coupled to the inner circumference of the first main body ring (111) and can be extended downward to a predetermined height. The first mounting inclined ring (112a) can be extended downward in a vertical direction or in an inwardly inclined direction from the inner circumference of the first main body ring (111). The first mounting inclined ring (112a) can be formed to a height that corresponds approximately to the thickness of the wafer (a). The first mounting inclined ring (112a) can be formed to have the same thickness as the first main body ring (111). Additionally, the first mounting inclined ring (112a) can be formed to have a thicker thickness than the first main body ring (111) in order to stably support the wafer (a).

[0056] The first horizontal mounting ring (112b) has a predetermined thickness and can be formed so that its outer edge is joined to the lower end of the first inclined mounting ring (112a) and extends horizontally inward. The first horizontal mounting ring (112b) may have a first mounting area (112c) on which the lower surface of the outer edge of the wafer (a) is mounted. The first horizontal mounting ring (112b) can be formed with a width necessary to stably support the wafer (a). The first horizontal mounting ring (112b) can be formed with the same thickness as the first vertical mounting ring. Additionally, the first horizontal mounting ring (112b) can be formed with a thicker thickness than the first inclined mounting ring (112a) to stably support the wafer (a).

[0057] The first support ring (113) may have a predetermined thickness and be formed so that its upper end is connected to the outer circumference of the first main body ring (111) and extends downward to a predetermined height. The first support ring (113) may extend downward in a vertical direction or in an inwardly inclined direction from the outer circumference of the first main body ring (111). The first support ring (113) may be formed to a height greater than the height of the first seating ring (112). The first support ring (113) may be formed to have the same thickness as the first main body ring (111). Additionally, the first support ring (113) may be formed to have a thicker thickness than the first main body ring (111) in order to stably support the first main body ring (111).

[0058]

[0059] The second edge ring (120) may include a second body ring (121), a second seating ring (122), and a second support ring (123). The second edge ring (120) may further include a second stop ring (124) and a second blocking groove (125).

[0060] The second edge ring (120) may be formed in an overall ring shape. The second edge ring (120) may be positioned at the first edge ring (110) to support the outer side of the first edge ring (110). Additionally, the outer side of the second edge ring (120) may be supported on the inner side of the rotational support (24). The second edge ring (120) may be formed integrally with the second main body ring (121), the second seating ring (122), and the second support ring (123). That is, the second edge ring (120) may be formed by processing a ring having a predetermined thickness and width to include the second main body ring (121), the second seating ring (122), and the second support ring (123).

[0061] As described above, the second edge ring (120) may be formed of a material having a higher thermal conductivity than the first edge ring (110). The second edge ring (120) may be formed of CVD-SiC. The second edge ring (120) may have a thermal conductivity of 320 to 3800 W / mK. The first edge ring (110) may have a specific heat of 640 to 700 J / kgK.

[0062] The second edge ring (120) may be formed with a thickness of 1.0 to 1.5 mm overall. The second edge ring (120) may be formed with a thickness greater than that of the first edge ring (110).

[0063] The second main body ring (121) may be formed in a ring shape having a predetermined width and thickness. The second main body ring (121) may be formed with an appropriate width and outer diameter to have the strength required to support the first edge ring (110) located on the inside and the wafer (a). The second main body ring (121) may be formed in a ring shape where the width is greater than the thickness. The second main body ring (121) may be formed with a thickness of 1.0 to 1.5 mm. The inner diameter of the second main body ring (121) may be formed to be larger than the outer diameter of the first edge ring (110).

[0064] The second mounting ring (122) may be formed in an "L" shape. More specifically, the second mounting ring (122) may include a second mounting inclined ring (122a) and a second mounting horizontal ring (122b). The second mounting ring (122) may be formed in a stepped shape extending downward from the upper surface of the second main body ring (121) to provide a second mounting area (122c) on which the outer circumference of the first edge ring (110) is mounted. The second mounting ring (122) is coupled to the inner side of the second main body ring (121) and can support the first edge ring (110) located on the inner side. The second mounting ring (122) may be formed such that the thickness of the second mounting area (122c) on which the first edge ring (110) is mounted is the same as or thicker than other parts of the second mounting ring (122). For example, the thickness of the second mounting area (122c) may be formed such that it is the same as or thicker than the thickness of the second main body ring (121).

[0065] The second mounting ring (122) can support the first support ring (113) of the first edge ring (110) which is mounted in the second mounting area (122c). More specifically, the second mounting ring (122) can support the lower end of the first support ring (113). The upper end of the second mounting ring (122) may be coupled to the inner end of the second main body ring (121) and may be located lower than the second main body ring (121). That is, the upper end of the second mounting inclined ring (122a) may be coupled to the inner end of the second main body ring (121), and the outer end may be coupled to the lower end of the second mounting inclined ring (122a). The second seating ring (122) may be formed with the same thickness as the second main body ring (121). Additionally, the second seating ring (122) may be formed with a thicker thickness than the second main body ring (121) to stably support the first edge ring (110).

[0066] The second seating inclined ring (122a) has a predetermined thickness and can be formed so that its upper end is coupled to the inner circumferential end of the second main body ring (121) and extends to a predetermined height in a downward direction. The second seating inclined ring (122a) can extend downward in a vertical direction or in an inwardly inclined direction from the inner circumferential end of the second main body ring (121). The second seating inclined ring (122a) can be formed to a height that corresponds approximately to the height of the first support ring (113). The second seating inclined ring (122a) can be formed to have the same thickness as the second main body ring (121). The second seating ring (122) can be formed to have a thickness of 1.0 to 1.5 mm overall. Additionally, the second mounting inclined ring (122a) may be formed with a thicker thickness than the second main body ring (121) to stably support the first edge ring (110).

[0067] The second horizontal mounting ring (122b) has a predetermined thickness and can be formed so that its outer edge is joined to the lower end of the second inclined mounting ring (122a) and extends horizontally inward. The second horizontal mounting ring (122b) may have a second mounting area (122c) on which the first support ring (113) of the first edge ring (110) is mounted. The second horizontal mounting ring (122b) can be formed with a width necessary to stably support the first support ring (113) of the first edge ring (110). The second horizontal mounting ring (122b) can be formed with the same thickness as the second vertical mounting ring. The second horizontal mounting ring (122b) can be formed with a thickness of 1.0 to 1.5 mm. Additionally, the second mounting horizontal ring (122b) may be formed with a thicker thickness than the first mounting inclined ring (112a) to stably support the first edge ring (110).

[0068] The second support ring (123) may have a predetermined thickness and be formed so that its upper end is connected to the outer end of the second main body ring (121) and extends downward to a predetermined height. The second support ring (123) may extend downward in a vertical direction or in an inwardly inclined direction from the outer periphery of the first main body ring (111). The second support ring (123) may be formed with a height smaller than that of the second seating ring (122). The second support ring (123) may be formed with the same thickness as the second main body ring (121). Additionally, the second support ring (123) may be formed with a thicker thickness than the second main body ring (121) to stably support the second main body ring (121).

[0069] The second stop ring (124) is ring-shaped and may be formed to protrude along the inner circumference of the second seating area (122c) from the upper surface of the second seating ring (122). The second stop ring (124) may be formed in a semicircular shape with a vertical cross-section convex upward or in a square shape with rounded corners. The second stop ring (124) may prevent the first support ring (113) seated in the second seating area (122c) from detaching from the second seating area (122c). The second stop ring (124) may be formed at a height such that its upper end is spaced apart from the lower surface of the first main body ring (111) when the first support ring (113) is seated in the second seating area (122c). The second support ring (123) can be formed integrally with the second seating ring (122).

[0070] The second blocking groove (125) may be formed as a ring-shaped groove extending from the lower surface of the second main body ring (121) upward. The second blocking groove (125) may reduce the vertical cross-sectional area of ​​the second main body ring (121), thereby reducing the transfer of heat to the outside through the second main body ring (121). The second blocking groove (125) may be formed with a predetermined depth and width on the lower surface of the second main body ring (121). The second blocking groove (125) may be formed with a predetermined depth to maintain the strength required for the second main body ring (121) to support the first edge ring (110). For example, the second blocking groove (125) may be formed with a depth of 0.4 to 0.7 times the total thickness of the second main body ring (121). Additionally, the second blocking groove (125) may be formed with a predetermined width to maintain the strength required for the second main body ring (121) to support the first edge ring (110). The second blocking groove (125) may be formed on the inner lower surface of the second main body ring (121). Additionally, the second blocking groove (125) may be located in the middle or on the outer side of the second main body ring (121).

[0071]

[0072] Next, an edge ring for wafer support according to another embodiment of the present invention will be described.

[0073] FIG. 3 is a vertical cross-sectional view of an edge ring for wafer support according to another embodiment of the present invention.

[0074] A wafer support edge ring (200) according to another embodiment of the present invention may include a first edge ring (110) and a second edge ring (220), with reference to FIG. 3. Compared to the wafer support edge ring (100) according to one embodiment of FIG. 2, the wafer support edge ring (200) may have the first edge ring (110) formed with the same or similar structure, and the structure of the second edge ring (220) may be formed differently. Therefore, the following description will focus on the second edge ring (220). Additionally, the wafer support edge ring (200) may be assigned the same reference numerals for configurations identical or similar to the wafer support edge ring (100) of FIG. 2, and specific descriptions may be omitted.

[0075] The second edge ring (220) may include a second body ring (121), a second seating ring (222), and a second support ring (123). The second edge ring (220) may further include a second stop ring (124) and a second blocking groove (125).

[0076] The second seating ring (222) may be formed in an "L" shape. More specifically, the second seating ring (222) may include a second seating inclined ring (122a) and a second seating horizontal ring (222b). The second seating ring (222) may have a second seating area (222c) on which the outer periphery of the first edge ring (110) or the first support ring (113) is seated. The thickness of the second seating area (222c) of the second seating ring (222) may be formed to be thinner than other parts of the second seating ring (222). Additionally, the thickness of the second seating area (222c) may be formed to be thinner than the thickness of the second main body ring (121). Accordingly, the second seating ring (222) can reduce the transfer of heat from the first support ring (113) of the first edge ring (110) to the second main body ring (121).

[0077] The second mounting horizontal ring (222b) may have a second mounting area (222c) formed therein where the first support ring (113) of the first edge ring (110) is mounted. The second mounting horizontal ring (222b) may be formed with a thinner thickness than the second mounting vertical ring. The second mounting horizontal ring (222b) may be formed with a thickness of 0.4 to 0.8 mm. Accordingly, the second mounting horizontal ring (222b) can reduce the transfer of heat from the first support ring (113) of the first edge ring (110) to the second mounting inclined ring (122a) and the second main body ring (121).

[0078]

[0079] Next, an edge ring for wafer support according to another embodiment of the present invention will be described.

[0080] FIG. 4 is a vertical cross-sectional view of an edge ring for wafer support according to another embodiment of the present invention.

[0081] A wafer support edge ring (300) according to another embodiment of the present invention may include a first edge ring (310) and a second edge ring (320), with reference to FIG. 4. Compared to the wafer support edge ring (100) according to one embodiment of FIG. 2, the wafer support edge ring (300) may have a different structure in some parts of the first edge ring (310) and the second edge ring (320). Therefore, the following description will focus on the parts where the structures of the first edge ring (310) and the second edge ring (320) are different. Additionally, the wafer support edge ring (300) may be given the same reference numerals for configurations identical or similar to the wafer support edge ring (100) of FIG. 2, and specific descriptions may be omitted.

[0082]

[0083] The first edge ring (310) may include a first body ring (111), a first seating ring (112), and a first support ring (313).

[0084] The first support ring (313) may be formed in a ring shape that protrudes downward from the outer end of the first main body ring (111). The first support ring (313) may be formed in a semicircular shape with a vertical cross-section that is convex downward or in a square shape with rounded corners. The first support ring (313) may be formed with a height smaller than the thickness of the first main body ring (111). The first support ring (313) may be supported by contacting the second seating area (222c) of the second edge ring (320) at its bottom or lower surface. Since the first support ring (313) is formed in a semicircular shape or a rounded square shape, the contact area with the second seating area (222c) of the second edge ring (320) may be reduced. Therefore, the first support ring (313) can reduce the transfer of heat to the second edge ring (320).

[0085] The second edge ring (320) may include a second body ring (121), a second seating ring (322), a second blocking groove (125), and a second support groove (326). The second edge ring (320) may be formed in a plate shape and a ring shape. The second edge ring (320) may be formed in a ring shape with a uniform thickness throughout. The second seating ring (322) may be formed with a thickness smaller than that of the second body ring (121). The second edge ring (320) may be formed with a thickness of 0.4 to 0.8 mm.

[0086] The second seating ring (322) can be coupled so as to extend outward from the lower outer surface of the second main body ring (121). That is, the inner surface of the second seating ring (322) can be coupled to the lower outer surface of the second main body ring (121). The upper surface of the second seating ring (322) can be stepped with respect to the upper surface of the second main body ring (121) to form a second seating area (322c). Since the second seating ring (322) is formed with a thickness smaller than that of the second main body ring (121), the transfer of heat from the first edge ring (310) to the second main body ring (121) can be reduced.

[0087] The second support groove (326) may be formed as a groove that extends upward from the outer lower surface of the second main body ring (121) and forms a ring shape along the lower surface. The second support groove (326) may provide a space for receiving a rotational projection ring of a rotational support member (24) located on the outer side. The second support groove (326) may be formed with a depth greater than the height of the rotational projection ring. Additionally, the second support groove (326) may be formed with a width greater than the width of the rotational projection ring. When the second support groove (326) is coupled with the rotational projection ring, the lower surface of the second main body ring (121) may come into contact with the upper surface of the rotational seating ring of the rotational support member (24). Therefore, the second support groove (326) can enable the second main body ring (121) to be stably supported by the rotational seating ring.

[0088]

[0089] The following describes the evaluation results of an edge ring for wafer support according to one embodiment of the present invention.

[0090] In this evaluation, wafer support edge rings were configured for each example as follows.

[0091] - Example 1: Edge ring in which the second blocking groove in FIG. 2 is omitted

[0092] - Example 2: Edge ring in which the second blocking groove in FIG. 3 is omitted

[0093] - Example 3: Edge ring of Fig. 3

[0094] - Example 4: Edge ring in which the second blocking groove is omitted in FIG. 4

[0095]

[0096] Figure 5 shows the measurement results for the temperature distribution of the wafer according to the embodiments of the present invention.

[0097] As shown in FIG. 5, the temperature difference between the middle and outer periphery of the wafer is not large, and the width of the region where the temperature is relatively lower at the outer periphery is formed small. Therefore, the edge ring according to the embodiments of the present invention was evaluated to reduce the temperature difference of the wafer.

[0098] Figure 6 is a simulation result of the temperature distribution of the edge ring according to an embodiment of the present invention.

[0099] As shown in FIG. 6, the second edge ring was evaluated to have a relatively lower temperature compared to the first edge ring. Therefore, the first edge ring is evaluated to reduce the heat transferred to the second edge ring. Additionally, in Example 1, the temperature of the outer periphery of the first edge ring was evaluated to be relatively lower compared to other examples. Therefore, the edge ring of Example 1 is evaluated to have a relatively lower efficiency in blocking heat transferred to the second edge ring compared to other examples. Furthermore, the edge rings of Examples 2 to 4 are evaluated to have relatively small temperature variations among the outer periphery of the first edge ring. Therefore, the edge rings of Examples 2 to 4 are evaluated to have similar efficiency in blocking heat transferred to the second edge ring.

[0100] Figure 7 is the result of measuring the change in average temperature over time of the wafer and edge ring in Example 2 of the present invention.

[0101] As shown in FIG. 7, the average temperature of the first edge ring is equal to or similar to the average temperature of the wafer depending on the heating time, but the second edge ring is evaluated to have a lower average temperature than the first edge ring. Therefore, the first edge ring of Example 2 is evaluated to efficiently block heat transferred to the second edge ring.

[0102]

[0103] The embodiments disclosed in this specification are merely the most preferred embodiments selected and presented to aid the understanding of those skilled in the art among various possible embodiments, and the technical concept of this invention is not necessarily limited or restricted only by these embodiments. Various changes, additions, and modifications are possible within the scope of the technical concept of this invention, and equivalent other embodiments can be implemented.

Claims

1. A first edge ring located on the outer side of the wafer and supporting the outer periphery of the wafer, and A wafer support edge ring characterized by including a second edge ring located on the outer side of the first edge ring and supporting the outer periphery of the first edge ring.

2. In Paragraph 1, A wafer support edge ring characterized in that the first edge ring and the second edge ring are formed from any one of silicon carbide (SiC), quartz, and graphite.

3. In Paragraph 1, A wafer support edge ring characterized in that the first edge ring and the second edge ring are formed of different materials.

4. In Paragraph 3, A wafer support edge ring characterized in that the first edge ring is formed of a material having a lower thermal conductivity than the second edge ring.

5. In Paragraph 3, The first edge ring is formed of sintered SiC, and A wafer support edge ring characterized in that the second edge ring is formed of CVD-SiC.

6. In Paragraph 1, The above-mentioned first edge ring is A first main body ring formed in a ring shape having a predetermined width and thickness, and A first mounting ring having a first mounting area formed in a stepped shape extending downward from the upper surface of the first main body ring, on which the outer periphery of the wafer is mounted, and It includes a first support ring having a predetermined thickness, wherein the upper end is coupled to the outer circumference of the first main body ring and extends to a predetermined height in a downward direction, The above second edge ring is A second main body ring formed in a ring shape having a predetermined width and thickness, and A second seating ring having a second seating area formed in a stepped shape extending downward from the upper surface of the second main body ring, on which the first support ring of the first edge ring is seated, and A wafer support edge ring characterized by having a predetermined thickness and including a second support ring, the upper end of which is coupled to the outer circumference of the second main body ring and extends to a predetermined height in the downward direction.

7. In Paragraph 6, The above-mentioned first seating ring is A first seating inclined ring, the upper end of which is coupled to the inner circumference of the first main body ring and extends downward to a predetermined height, and It includes a first horizontal mounting ring, the outer end of which is coupled to the lower end of the first mounting inclined ring and extends horizontally inward to form the first mounting area. The above second seating ring is A second seating inclined ring, the upper end of which is coupled to the inner circumference of the second main body ring and extends downward to a predetermined height, and A wafer support edge ring characterized by including a second mounting horizontal ring, the outer end of which is coupled to the lower end of the second mounting inclined ring and extends inwardly in a horizontal direction to form the second mounting area.

8. In Paragraph 7, A wafer support edge ring characterized in that the thickness of the second seating area is thinner than the thickness of the second main body ring.

9. In Paragraph 6, A wafer support edge ring characterized by the above-mentioned second main body ring further including a second blocking groove in the shape of a groove that extends from the lower surface to the upper surface and forms a ring shape.

10. In Paragraph 7, A wafer support edge ring characterized by the second seating ring being ring-shaped and further including a second stop ring formed by protruding along the inner circumference of the second seating area from the upper surface of the second seating ring.

11. In Paragraph 1, The above-mentioned first edge ring is A first main body ring formed in a ring shape having a predetermined width and thickness, and A first mounting ring having a first mounting area formed in a stepped shape extending downward from the upper surface of the first main body ring, on which the outer periphery of the wafer is mounted, and It includes a first support ring, the upper end of which is coupled to the outer circumference of the first main body ring and extends downward, and is formed with a height smaller than the thickness of the first main body ring. The above second edge ring is A second main body ring formed in a ring shape having a predetermined width and thickness, and A second seating ring having a second seating area formed in a stepped shape extending downward from the upper surface of the second main body ring, on which the first support ring is seated, and A wafer support edge ring characterized by including a second support groove that extends upward from the outer lower surface of the second main body ring and is formed as a ring-shaped groove along the lower surface.

12. In Paragraph 11, A wafer support edge ring characterized by the above-mentioned second main body ring further including a second blocking groove in the shape of a groove that extends from the lower surface to the upper surface and forms a ring shape.

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