Substrate with purge gas flow path

Abstract

The present invention relates to a susceptor having a purge gas flow path for supplying a purge gas. The present invention provides a susceptor including a plate in which a heat generating body layer is embedded, and a hollow type shaft joined to a lower end of the plate, the plate having a purge gas flow path layer disposed on a different plane from the heat generating body layer, the purge gas flow path layer including an inner flow path and a plurality of radial branch flow paths extending outward from the inner flow path.

Description

TECHNICAL FIELD

[0001] The present invention relates to a susceptor, and more particularly, to a susceptor having a purge gas flow path for supplying a purge gas. BACKGROUND

[0002] Generally, a semiconductor device or a display device is manufactured by a semiconductor process of sequentially stacking a plurality of thin film layers including a dielectric layer and a metal layer on a glass substrate, a flexible substrate, or a semiconductor wafer substrate, and then performing patterning. The thin film layers are sequentially deposited on the substrate by a Chemical Vapor Deposition (CVD) process or a Physical Vapor Deposition (PVD) process. The CVD process includes a Low Pressure CVD (LPCVD) process, a Plasma Enhanced CVD (PECVD) process, a Metal Organic CVD (MOCVD) process, etc. A susceptor for supporting the glass substrate, the flexible substrate, the semiconductor wafer substrate, etc. and processing the semiconductor process is provided in such a CVD device and a PVD device. Such a susceptor is provided in the CVD device and the PVD device, and can have a heating plate in which a heating element is built-in to heat the substrate while supporting the substrate. In addition, the susceptor can form a plasma by providing a high frequency (RF) electrode instead of the heating element or additionally providing the high frequency (RF) electrode on the basis of the heating element in a process of an etching process, etc. for the thin film layer formed on the substrate.

[0003] In addition, in order to prevent uneven deposition of a local thin film of an end portion of a wafer in a process of a thin film deposition process, etc. using the susceptor, it is necessary to provide a purge gas flow path for supplying a purge gas to the end portion of the wafer.

[0004] In addition, the purge gas flow path formed in the interior of the susceptor can have a flow path of a radial structure to secure symmetry with respect to the center of the plate.

[0005] However, in the radial branch flow path, the lengths of the flow paths from the axis side to which the purge gas flows are different from each other, and thus there is a problem in that it is difficult to supply the purge gas uniformly to the circumference of the wafer, or the plurality of radial branch flow paths are branched at a specific branch point of junction with the axis, and thus there is a problem in that cracks are easily generated at the branch point due to a large pressure applied when the plate is press-fitted with the axis. SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] The present application is made to solve the above problems, and has an object to provide a susceptor having a purge gas flow path structure capable of supplying a uniform purge gas to the vicinity of the edge of a wafer.

[0008] Further, the present application has an object to provide a susceptor having a purge gas flow path structure suitable for suppressing cracking at the time of press-fitting of a plate and a shaft.

[0009] Further, the present application has an object to provide a susceptor structure capable of suppressing heat transfer from a plate to a shaft.

[0010] Means for solving the problems

[0011] To solve the above-described technical problems, the present application provides a ceramic susceptor including a plate in which a heat generating body layer is embedded, and a hollow shaft fitted to the lower end of the plate, the plate having a purge gas flow path layer disposed on a different plane from the heat generating body layer, the purge gas flow path layer including: an inner flow path; and a plurality of radial branch flow paths extending outward from the inner flow path.

[0012] In the present application, the hollow shaft has a side wall extending in the length direction and a connecting portion forming a fitting portion with the plate at the end of the side wall, and the inner flow path can be formed in a shape matching the connecting portion of the shaft.

[0013] In the present application, the inner flow path and the connecting portion can be circular. At this time, it is preferable that the inner flow path be limited inside the outline of the connecting portion when projected onto the plane of the plate.

[0014] In the present application, the inner flow path is disposed at a position closer to the center of the plate within the outline of the connecting portion.

[0015] Further, in the present application, the ratio of the width of the inner flow path to the width of the connecting portion is preferably 0.1 to 0.7.

[0016] In the present application, it is preferable that the shaft have a side wall flow path extending in the length direction of the side wall within the side wall, the end portion of the side wall flow path being aligned with the inner flow path.

[0017] At this time, a mounting member combined with the end portion of the shaft and a purge line formed along the side wall circumference of the end portion of the shaft can also be included, the purge line being connectable to the side wall flow path.

[0018] In the present application, it is preferable that the end portion of the side wall flow path be located at an intermediate position between the radial branch flow paths adjacent to each other on the inner flow path.

[0019] In the present application, preferably, the shaft has a plurality of side wall flow paths extending along the length direction of the side wall inside the side wall, and each end portion of each of the plurality of side wall flow paths is aligned with the internal flow path.

[0020] In the present application, the plurality of radial branch flow paths are preferably symmetrical with respect to the center of the plate. In addition, the number of the plurality of radial branch flow paths in the present application can be 4 to 10.

[0021] Effects of the Invention

[0022] According to the susceptor of the present application, by providing the purge gas flow paths symmetrical with respect to the center of the plate, it is possible to supply the purge gas uniformly to the vicinity of the edge of the wafer.

[0023] In addition, according to the susceptor of the present application, by dispersing the branch points of the flow paths of the purge gas, it is possible to provide a purge gas flow path pattern capable of suppressing cracks generated at the press-fitting of the plate and the shaft.

[0024] Further, according to the susceptor of the present application, it is possible to provide a susceptor structure capable of suppressing the loss of heat generated from the heat generating body of the plate to the shaft. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1A and Figure 1B is a diagram schematically showing a purge gas flow path structure of a susceptor according to an embodiment of the present application.

[0026] Figure 2A and Figure 2B is Figure 1B is a sectional view of the susceptor in

[0027] Figure 3A and Figure 3B is a diagram for explaining a flow path structure of a susceptor according to an embodiment of the present application.

[0028] Figure 4 is a photograph for explaining a temperature variation based on a shaft position in a conventional susceptor.

[0029] EXPLANATION OF REFERENCE NUMERALS

[0030] 110: plate

[0031] 112: heat generating body layer

[0032] 114: internal flow path

[0033] 115: communication hole

[0034] 116: branch flow path

[0035] 120: shaft

[0036] 122: side wall

[0037] 124: connecting portion

[0038] 128: side wall flow path

[0039] 130: mount DETAILED DESCRIPTION

[0040] Hereinafter, the present application will be described in detail with reference to the accompanying drawings. At this time, the same constituent elements in each drawing are denoted by the same reference numerals as far as possible. In addition, the explanation of known functions and / or configurations will be omitted. The following disclosure will mainly explain the parts necessary for understanding the operation of various embodiments, and the explanation of elements that can blur the gist of the explanation will be omitted. In addition, some of the constituent elements in the drawings can be enlarged, omitted, or schematically shown. The size of each constituent element cannot fully reflect the actual size, and thus the contents described herein are not limited by the relative size or interval of the constituent elements shown in each drawing.

[0041] In explaining embodiments of the present application, if it is judged that the detailed explanation of the known technology related to the present application unnecessarily obscures the gist of the present application, the detailed explanation thereof will be omitted. Also, the terms described later are terms defined in consideration of the functions of the present application, and can be different according to the intention of the user, the operator, or the precedent. Therefore, the definition thereof should be made based on the contents of the entire specification. The terms used in the present specification are used only to explain embodiments of the present application, and are not intended to limit. Unless otherwise specified, the singular expression should include the plural expression. The expression "include" or "have" or the like in the present specification is used to indicate any feature, number, step, action, component or a combination thereof, and should not be understood as excluding the existence or possibility of addition of one or more other features, numbers, steps, actions, components or combinations thereof.

[0042] In addition, the first, second, and the like terms, although can be used to explain various constituent elements, the constituent elements are not limited to the terms, and the terms are used only to distinguish one constituent element from another.

[0043] Figure 1A FIG. 1 is a view schematically showing a purge gas flow path structure formed on a plate of a susceptor according to an embodiment of the present application, Figure 1B FIG. 2 is a view schematically showing a state in which a shaft is coupled to the plate.

[0044] Referring to Figure 1A For example, the purge gas flow paths 114, 116 for supplying a purge gas from the center of the plate to the outside are provided inside the plate 110.

[0045] As shown in the figure, the purge gas flow paths 114 and 116 may include: an internal flow path 114; and radially branched flow paths 116 extending from the internal flow path 114 to the outside of the plate 110. In this invention, the internal flow path 114 may follow the shape of the plate. As shown in the figure, a circular internal flow path 114 can be formed according to the shape of a circular plate. However, in this invention, it is obvious that the shape of the internal flow path 114 is not necessarily limited by the shape of the plate.

[0046] In this invention, the internal flow path 114 can be formed in a manner that matches the circumferential direction of the shaft 110, or in a manner that corresponds to the engagement portion of the shaft 110.

[0047] In this invention, the plate 110 can be made of plate-shaped ceramic. For example, the ceramic material may include at least one substance or a compound thereof selected from the group consisting of Al2O3, Y2O3, ZrO2, TiN, AlN, TiC, MgO, CaO, CeO2, TiO2, BxCy, BN, SiO2, SiC, YAG, YAP, and YAM, preferably aluminum nitride (AlN). Additionally, when the ceramic material is AlN, the composition of the plate 110 may also include at least one metal compound (preferably a metal oxide) selected from the group consisting of Y, Mg, Al, and Ti.

[0048] Furthermore, multiple radial branch flow paths 116 branch off at predetermined intervals or angles along the circumference of the inner flow path 114. While the number of radial branch flow paths or the spacing between them is not specifically limited in this invention, the multiple radial branch flow paths 116 are preferably symmetrically distributed at predetermined angular intervals relative to the center of the plate 110 to supply a uniform purge gas along the outer periphery of the plate 110. Additionally, in this invention, for example, four, six, eight, ten, twelve, or more radial branch flow paths may be provided.

[0049] Furthermore, in this invention, it is natural that the flow path widths of the internal flow path 114 and the radial branch flow path 116 can be designed to be the same or different from each other.

[0050] Figure 1B This is a schematic diagram showing the combined state of plate 110 and shaft 120. Referring to the accompanying drawing, when the plane of plate 110 is projected, the position of the internal flow path 114 of plate 110 overlaps with the position of the joint of shaft 120. Preferably, the position of the internal flow path 114 is confined within the joint of shaft 120.

[0051] Figure 2A and Figure 2B These are exemplarily shown in Figure 1BFIG. 2 is a view of a cross section taken in the A-A' direction and the B-B' direction in FIG. 1.

[0052] Referring to Figure 2A A heat generating body layer 112 can be embedded in the inside of the plate 110. The heat generating body layer 112 can be composed of a coil or a plate-shaped metal heat generating body, and can be formed with a predetermined pattern on a plane. In addition, the heat generating body layer 112 can form a multi-layer structure or a plurality of zones for implementing precise temperature control. In the present application, the heat generating body forming the heat generating body layer 112 is at least one metal selected from a group consisting of tungsten (W), molybdenum (Mo), silver (Ag), gold (Au), niobium (Nb), titanium (Ti), or an alloy thereof, and is preferably made of molybdenum (Mo). The heat generating body layer 112 can be connected to a power terminal through a power supply rod (not shown). The power supply rod can pass through the inside space of the shaft 120 and extend to the outside through a mount.

[0053] In addition, a purge gas flow path layer can be provided in the inside of the plate 110 at the lower end of the heat generating body layer 112, and the purge gas flow path layer includes an internal flow path 114 and a radial branch flow path 116 branched from the internal flow path 114.

[0054] The purge gas flow path layer is provided on a different plane from the heat generating body layer 112. In the present application, although the case where the purge gas flow path layer is provided at the lower end of the heat generating body layer 112 is shown, it is self-evident that the purge gas flow path layer can be provided at the upper end of the heat generating body layer 112.

[0055] In addition, a hollow shaft 120 can be provided at the lower end of the plate 110. The hollow shaft 120 has a side wall 122 extending in the axial direction, and a connecting portion 124 forming a joint with the plate 110 at one end of the side wall 122. In the present application, the connecting portion 124 can be a flange, but is not limited thereto. The other end 126 of the side wall 122 can be combined with a structure such as a mount (not shown).

[0056] The shaft 120 can be made of a ceramic material. For example, the ceramic material can include at least one substance selected from the group consisting of AI2O3, Y2O3, ZrO2, TiN, AlN, TiC, MgO, CaO, CeO2, TiO2, BxCy, BN, SiO2, SiC, YAG, YAP, and YAM, or a compound thereof, and preferably, aluminum nitride (AlN). In addition, when the ceramic material is AlN, the composition of the plate 110 can further include at least one metal compound (preferably, a metal oxide) selected from the group consisting of Y, Mg, Al, and Ti. The shaft 120 is preferably made of a ceramic material having low thermal conductivity. For example, the shaft 120 can be an AlN sintered body including 2 wt% or less of yttria as a sintering aid, and the thermal conductivity can be controlled by the content of the sintering aid such as yttria. By artificially introducing impurities into the inside of AlN, for example, by adding AI2O3, or by maintaining the content of metal elements in the sintered body to be 1000 ppm or less, a shaft having extremely low thermal conductivity can be implemented.

[0057] Referring to Figure 2B A side wall flow path 128 for flowing a purge gas is provided in the side wall 122 of the shaft 120. The side wall flow path 128 extends in the axial direction of the shaft 120 within the side wall 122 of the shaft 120, and is connected to the internal flow path 114 of the plate 110. For this purpose, a communication hole 115 can be provided at the lower end of the internal flow path 114 of the plate 110. In the present application, the side wall flow path 128 can be spaced apart from the inner wall and the outer wall of the shaft 120 by 3 mm or more.

[0058] In the present application, the communication hole 115 is aligned with the internal flow path 114 and the side wall flow path 128. At this time, preferentially, the communication hole 115 is formed at a position on the internal flow path 114 away from the branch points of the radially branched flow paths 116, that is, at a non-crossing point between the internal flow path 114 and the radially branched flow paths 116. This prevents the gas flowing from the communication hole 115 from being excessively discharged to a specific radially branched flow path 116. Preferably, the communication hole 115 is located at a position on the internal flow path 114 between the branch points of the radially branched flow paths 116 adjacent to each other. In the present application, the lengths of the plurality of radially branched flow paths 116 can be set to be the same.

[0059] Although two side wall flow paths 128 are shown in the drawings, it is of course understood that the present application is not limited thereto. One side wall flow path 128 or a plurality of side wall flow paths 128 of two or more can be provided, and in order to flow a uniform purge gas, a proper number of communication holes can be provided.

[0060] Further, in the present application, the side wall flow path 128 is shown as a one-dimensional flow path extending in the axial direction of the shaft 120 and having a predetermined length, but the present application is not limited thereto, and it is self-evident that a two-dimensional cylindrical flow path extending in the circumference of the side wall 122 of the shaft 120.

[0061] The shaft 120 can be joined with the plate 110. At this time, a ceramic adhesive or a ceramic grease can be used as a joining agent. In the present application, the ceramic adhesive or the ceramic grease can be one using aluminum nitride as a main raw material, but is not limited thereto.

[0062] Referring to Figure 1A , Figure 1B , Figure 2A and Figure 2B , the flow path structure of the present application can have the advantage of dispersing structural weak portions in the interior of the plate by distributing branch points to a plurality of positions of the internal flow path. As described above, by dispersing the flow path branch points of the purge gas, a purge gas flow path pattern capable of suppressing the generation of cracks during the press joining of the plate and the shaft can be provided.

[0063] Further, at the same time, the branch structure can uniformly eject the purge gas at the end portions of the plate by realizing a radial structure symmetrical with respect to the center of the plate.

[0064] Further, the flow path structure of the present application can provide a heat insulation mechanism that suppresses the transfer of heat to the shaft. In this regard, a description will be given with reference to Figure 4

[0065] Figure 3A and Figure 3B show that the internal flow path 114 has different areas in the projection plane of the plate. In Figure 3A and Figure 3B , the internal flow path 114 is located inside the outline of the connecting portion 122, but the width w1 of the internal flow path 114 can be adjusted.

[0066] As shown in Figures 3A-3B , if the width w1 of the internal flow path 114 increases, the flow path area provided between the heat generating body layer 112 and the connecting portion 124 of the shaft 120 increases. In the present application, since the transfer of heat through the flow path is performed by radiation or convection, it can function as a heat blocking or insulating element compared to a plate body having a high thermal conductivity. In particular, since heat loss of the shaft 120 occurs at the joint portion of the shaft 120 and the plate 110 (i.e., the shaft connecting portion), it is possible to suppress the heat loss from the heat generating body layer 112 by aligning the internal flow path 114 with the connecting portion 124 of the shaft 120.

[0067] ​In the present application, the width wl of the internal flow path 114 can be designed to be smaller than the width w2 of the connecting portion 124 of the shaft 120. In the present application, the ratio of the width wl of the internal flow path 114 to the width w2 of the connecting portion 124 can be 0.1 or more, 0.2 or more, 0.3 or more, 0.4 or more, or 0.5 or more. In addition, the ratio of the width wl of the internal flow path 114 to the width w2 of the connecting portion 124 can be 1 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, or 0.4 or less. The ratio is preferably 0.1 to 0.7. In addition, according to the present application, by adjusting the width wl of the internal flow path 114, heat loss through the shaft 120 can be prevented or the generation of cracks can be suppressed. For example, if the ratio of the width wl of the internal flow path 114 to the width w2 of the connecting portion 124 does not reach 0.1, it is difficult to prevent heat loss, and if the ratio exceeds 0.7, cracks can be generated.

[0068] In addition, although the internal flow path 114 is shown as being disposed at the center of the profile of the connecting portion 124 in the drawing, the present application is not limited thereto. In the present application, the internal flow path 114 can be disposed closer to the center of the plate 110 inside (on the inner side) of the profile of the connecting portion 124, or can be disposed in a manner biased toward the outer side of the plate 110.

[0069] Figure 4 is a photograph for explaining temperature changes based on the position of the shaft in a conventional susceptor. The susceptor of Figure 4 was operated at a temperature of 650°C, and the temperatures measured at each fulcrum ①, ②, ③, ④, ⑤ are shown in Table 1 below.

[0070] [Table 1]

[0071] fulcrum temperature ① 609.7℃ ② 529.0℃ ③ 468.0℃ ④ 404.5℃ ⑤ 327.9℃

[0072] As can be seen from Table 1, the vicinity of the mount is exposed to a high-temperature environment of 300°C or more. Heat generated in the heater plate is transmitted through the shaft, and the temperature reaches a high temperature of 300°C or more in the lower end region ⑤ for mounting the mount 130, and thus a problem of melting of the O-ring for sealing the mount 130 occurs, and in a serious case, a problem of release of the vacuum of the chamber can occur. Therefore, the purge gas through the side wall flow path 128 of the side wall 122 of the shaft 120 can be used as a cooling gas. That is, by forming a purge line along the circumference of the side wall 122 at the lower end portion of the shaft 120, it is possible to reduce the amount of heat transmitted to the mount 130.

[0073] As described above, in the present application, specific matters such as specific constituent elements and limited examples and drawings have been described, but this is provided only to assist in understanding the overall of the present application, and the present application is not limited to the described examples, and a person of ordinary skill in the art to which the present application pertains can make various modifications and changes within the scope of the essential characteristics of the present application. Therefore, the spirit of the present application should not be limited to the described examples and determined, and all technical ideas of equivalent or equivalent changes to the appended claims should be interpreted as included within the scope of the present application.

Claims

1. A susceptor comprising a plate in which a heat-generating body layer is embedded, and a hollow shaft joined to a lower end of the plate, characterized in that, the plate has a purge gas flow path layer disposed in a different plane from the heat-generating body layer, the purge gas flow path layer includes: an inner flow path; and a plurality of radially branched flow paths extending outward from the inner flow path, the shaft has: a side wall extending in the length direction of the shaft; and a connecting portion forming a joint with the plate at the end of the side wall, the inner flow path is formed in a shape matching the connecting portion of the shaft, in a projection onto the plane of the plate, the inner flow path is disposed inside the outline of the connecting portion, the shaft has a side wall flow path extending in the length direction of the side wall inside the side wall, in the plate, a communication hole is formed at the lower end of the inner flow path, the communication hole aligning with the side wall flow path and the inner flow path.

2. The susceptor according to claim 1, characterized in that, the inner flow path and the connecting portion are formed in a circular shape.

3. The susceptor according to claim 1, characterized in that, the inner flow path is disposed closer to the center of the plate inside the outline of the connecting portion.

4. The susceptor according to claim 1, characterized in that, the ratio of the width of the inner flow path to the width of the connecting portion is 0.1 to 0.

7.

5. The susceptor according to claim 1, characterized in that, the end of the side wall flow path is located at an intermediate position between adjacent radially branched flow paths on the inner flow path.

6. The base of claim 1, wherein further comprising: a mount coupled to the end of the shaft; and a purge line formed along the side wall circumference of the end of the shaft, the purge line is connected to the side wall flow path.

7. The susceptor according to claim 1, characterized in that, the shaft has a plurality of side wall flow paths extending in the length direction of the side wall inside the side wall, each end of each of the plurality of side wall flow paths aligns with the inner flow path.

8. The susceptor according to claim 1, characterized in that, the plurality of radially branched flow paths are symmetric with respect to the center of the plate.

9. The susceptor according to claim 1, characterized in that, the number of the plurality of radially branched flow paths is 4 to 10.

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