Susceptor including purge gas flow passage

Abstract

To provide a susceptor that suppresses loss, due to a shaft, of heat generated from a heating element of a plate.SOLUTION: Disclosed is a susceptor including a purge gas channel for supplying purge gas. The present disclosure provides a susceptor including: a plate 110 having a heating element layer 112 embedded therein; and a hollow shaft 120 joined to a lower end of the plate. The plate includes a purge gas channel layer disposed on a plane different from that of the heating element layer. The purge gas channel layer includes an internal channel 114, and multiple radial branch channels 116 extending outward from the internal channel.SELECTED DRAWING: Figure 2A

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 Art

[0002] Generally, a semiconductor device or a display device is manufactured by a semiconductor process in which a plurality of thin film layers including a dielectric layer and a metal layer are sequentially laminated on a glass substrate, a flexible substrate, or a semiconductor wafer substrate and then patterned. These 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 chemical vapor deposition (LPCVD) process, a plasma enhanced chemical vapor deposition (PECVD) process, a metal organic CVD (MOCVD) process, and the like. Such CVD apparatuses and PVD apparatuses are provided with a susceptor for supporting a glass substrate, a flexible substrate, a semiconductor wafer substrate, etc. and processing a semiconductor process. Such a susceptor can be provided with a heater plate having a heating element for heating the substrate while supporting the substrate, installed in the CVD apparatus and the PVD apparatus. Further, the susceptor may be provided with a radio frequency (RF) electrode instead of or in addition to the heating element, and may also be used for plasma formation in an etching process of a thin film layer formed on the substrate.

[0003] On the other hand, in order to suppress non-uniform deposition of a thin film at the end of a wafer in a thin film deposition process using a susceptor, etc., it is necessary to provide a purge gas flow path for supplying a purge gas to the end of the wafer.

[0004] On one hand, the purge gas flow path formed inside the susceptor can have a radial flow path structure to ensure symmetry with respect to the center of the plate.

[0005] However, since the lengths of the radial flow paths from the flow path on the shaft side where the purge gas flows in are different, there is a problem that it is difficult to uniformly supply the purge gas around the wafer, or at a specific point where a plurality of radial flow paths branch off when joining with the shaft, there is a problem that cracks are likely to occur at the branch point due to the large pressure applied during the pressure joining of the plate and the shaft.

Summary of the Invention

Problems to be Solved by the Invention

[0006] The present invention has been devised to solve the above problems, and an object of the present invention is to provide a susceptor having a purge gas flow path structure capable of uniformly supplying the purge gas near the wafer edge.

[0007] Another object of the present invention is to provide a susceptor having a purge gas flow path structure suitable for suppressing cracks generated during pressure joining of the plate and the shaft.

[0008] Another object of the present invention is to provide a susceptor structure capable of suppressing heat transfer from the plate to the shaft.

Means for Solving the Problems

[0009] In order to achieve the above technical problems, the present invention provides a susceptor including a plate in which a heating element layer is embedded and a hollow shaft joined to the lower end of the plate, wherein the plate includes a purge gas flow path layer disposed on a plane different from the heating element layer, and the purge gas flow path layer includes an internal flow path and a plurality of radial flow paths extending outward from the internal flow path.

[0010] In the present invention, the hollow shaft includes a side wall extending in the longitudinal direction and a connecting portion that forms a joining portion with the plate at the end of the side wall, and the internal flow path can have a shape corresponding to the connecting portion of the shaft.

[0011] In the present invention, the internal flow path and the connecting portion may be circular. At this time, on the plane obtained by projecting the plate, it is preferable that the internal flow path is limited within the contour of the connecting portion.

[0012] In the present invention, the internal flow path may be arranged relatively close to the center of the plate within the contour of the connecting portion.

[0013] Further, in the present invention, the ratio of the width of the internal flow path to the width of the connecting portion is preferably 0.1 to 0.7.

[0014] In the present invention, the shaft includes a side wall flow path extending in the longitudinal direction of the side wall within the side wall, and it is preferable that the end of the side wall flow path is aligned with the internal flow path.

[0015] At this time, it further includes a mount coupled to the end of the shaft, and further includes a purge line along the periphery of the side wall at the end of the shaft, and the purge line may be connected to the side wall flow path.

[0016] In the present invention, it is preferable that the end of the side wall flow path is located at an intermediate point between adjacent radial flow paths on the internal flow path.

[0017] In the present invention, the shaft includes a plurality of side wall flow paths extending in the longitudinal direction of the side wall within the side wall, and it is preferable that each end of the plurality of side wall flow paths is aligned with the internal flow path.

[0018] In the present invention, it is preferable that the plurality of radial channels are symmetric with respect to the center of the plate. Also, in the present invention, the number of the plurality of radial channels may be 4 to 10.

Advantages of the Invention

[0019] According to the present invention, it becomes possible to provide a purge gas channel that is symmetric with respect to the center of the plate and uniformly supply purge gas near the edge of the wafer.

[0020] Also, according to the present invention, it becomes possible to provide a purge gas channel pattern that disperses the channel branching points of the purge gas and suppresses the occurrence of cracks during the pressure bonding of the plate and the shaft.

[0021] Also, according to the present invention, it becomes possible to provide a susceptor structure that suppresses the loss of heat generated from the heating element of the plate to the shaft.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2A

Figure 2B

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0023] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Here, the same reference numerals are given to the same components in each figure as much as possible. Also, detailed descriptions of functions and / or configurations that are already known are omitted. The content disclosed below focuses on the parts necessary for understanding the operations according to various embodiments, and descriptions of elements that may obscure the gist of the description are omitted. Also, some components in the drawings can be illustrated exaggeratedly, omitted, or schematically. The size of each component does not entirely reflect the actual size, and thus, the content described herein is not limited by the relative size and spacing of the components depicted in each figure.

[0024] When describing embodiments of the present invention, if it is determined that a specific description of a known technique related to the present invention may obscure the gist of the present invention, the detailed description thereof is omitted. And the terms described below are terms defined in consideration of the functions in the present invention, and they can be changed depending on the intention or convention of the user, operator, etc. Therefore, the definition should be given based on the content throughout this specification. The terms used in the detailed description are merely for describing the embodiments of the present invention and should never be restrictive. Unless otherwise specified, the singular form of the expression includes the meaning of the plural form. In this description, expressions such as "including" or "comprising" are for indicating a certain characteristic, number, step, operation, element, part thereof, or combination, and should not be construed as excluding the existence or possibility of one or more other characteristics, numbers, steps, operations, elements, part thereof, or combination other than those described.

[0025] Note that terms such as first, second, etc. may be used to describe various components, but the various components are not limited by these terms, and these terms are only used for the purpose of distinguishing one component from another.

[0026] (a) of FIG. 1 is a diagram schematically showing a purge gas flow path structure formed on a susceptor plate according to an embodiment of the present invention, and (b) of FIG. 1 is a diagram schematically showing a state in which a shaft is coupled to the plate.

[0027] Referring to FIG. 1(a), illustratively, inside the plate 110, purge gas flow paths 114 and 116 for supplying purge gas from the center of the plate to the outside are provided.

[0028] As shown in the figure, the purge gas flow path includes an internal flow path 114 and a radial branch flow path 116 extending from the internal flow path to the outside of the plate. In the present invention, the internal flow path 114 may follow the shape of the plate. As shown in the figure, a circular internal flow path 114 is formed according to the circular plate shape. However, in the present invention, it goes without saying that the shape of the internal flow path is not necessarily limited to the plate shape.

[0029] In the present invention, the internal flow path may be formed to conform to the circumferential direction of the shaft or may be formed to correspond to the joining portion of the shaft.

[0030] In the present invention, the plate 110 may be formed of a plate-shaped ceramic. Illustratively, 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, B x C y , BN, SiO2, SiC, YAG, YAP, and YAM, and preferably may be aluminum nitride (AlN). On the other hand, when the ceramic material is AlN, the plate composition may further include at least one metal compound, preferably a metal oxide, selected from the group consisting of Y, Mg, Al, and / or Ti.

[0031] On one side, a plurality of radial channels 116 branch out at regular intervals or at a fixed angle along the periphery of the internal channel 114. In the present invention, the number of the radial channels and the interval between the channels are not particularly limited. However, in order to supply the purge gas uniformly along the outer periphery of the plate, it is preferable that the plurality of radially branched channels 116 are symmetrically distributed at a fixed angular interval with respect to the center of the plate. Further, in the present invention, for example, 4, 6, 8, 10, 12 or more radial channels may be provided.

[0032] Moreover, in the present invention, it goes without saying that the channel widths of the internal channel 114 and the radial channels 116 may be designed to be the same as or different from each other.

[0033] FIG. 1(b) is a diagram schematically showing a state in which the plate 110 and the shaft 120 are coupled. Referring to this figure, when projected onto the plate plane, the position of the internal channel 114 of the plate overlaps with the position of the joining portion of the shaft 120, and preferably, the position of the internal channel 114 may be limited within the joining portion of the shaft 120.

[0034] FIGS. 2A and 2B are diagrams schematically showing cross-sections cut in the directions of A-A' and B-B' in FIG. 1(b), respectively.

[0035] Referring to FIG. 2A, a heating element layer 112 is embedded in the plate 110. The heating element layer may be composed of a metal heating element in the shape of a coil or a plate, and can form a predetermined pattern in a plane. Further, the heating element layer 112 can have a multilayer structure or form a multi-zone for precise temperature control. In the present invention, the heating element forming the heating element layer may be composed of at least one metal selected from the group consisting of tungsten (W), molybdenum (Mo), silver (Ag), gold (Au), niobium (Nb) and titanium (Ti) or an alloy thereof, and preferably, it may be composed of molybdenum (Mo). The heating element 112 may be connected to a power supply terminal via a power supply rod (not shown). The power supply rod may pass through the internal space of the shaft 120 and extend to the outside through a mount.

[0036] On the other hand, inside the plate below the heating element 112, a purge gas flow path layer including an internal flow path 114 and a radial flow path 116 branching from the internal flow path 114 is provided.

[0037] The purge gas flow path layer is provided on a plane different from the heating element layer 112. Although it is shown in the present invention that the flow path layer is provided below the heating element layer, it goes without saying that the flow path layer may be provided above the heating element layer.

[0038] On the other hand, a hollow shaft 120 is provided below the plate 110. The shaft includes a side wall 122 extending in the axial direction and a connecting portion 124 forming a joint portion with the plate 110 at one end of the side wall. In the present invention, the connecting portion 124 may be a flange, but is not limited thereto. The other end 126 of the side wall may be coupled to a structure such as a mount (not shown).

[0039] The shaft 120 may be formed of a ceramic material. Exemplarily, the ceramic material is Al2O3, Y2O3, ZrO2, TiN, AlN, TiC, MgO, CaO, CeO2, TiO2, B x C yIt may contain at least one substance selected from the group consisting of BN, SiO2, SiC, YAG, YAP, and YAM, or a compound thereof, and preferably may be aluminum nitride (AlN). On the other hand, when the ceramic material is AlN, the plate composition may further contain at least one metal compound selected from the group consisting of Y, Mg, Al, and / or Ti, preferably a metal oxide. Preferably, the shaft may be made of a ceramic material with low thermal conductivity. Exemplarily, the shaft may be an AlN sintered body containing 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 AlN together with the addition of Al2O3 or maintaining the content of metal elements in the sintered body at 1000 ppm or less, a shaft with a very low thermal conductivity can be realized.

[0040] Referring to FIG. 2B, a side wall flow path 128 for the flow of 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 within the side wall of the shaft 120 and communicates with the internal flow path 114 of the plate. For this purpose, a communication hole 115 may be provided at the lower end of the internal flow path 114 of the plate 110. In the present invention, the side wall flow path may be separated from the inner wall and the outer wall of the shaft by at least 3 mm or more.

[0041] In the present invention, the communication hole 115 is aligned with the internal flow path 114 and the side wall flow path. At this time, the communication hole 115 is preferably formed at a position away from the branch point of the radial flow path 116 in the internal flow path 114, that is, at a non-intersecting point between the internal flow path and the radial flow path. This prevents the gas flowing in from the communication hole 115 from being excessively discharged into a specific radial flow path 116. Preferably, the communication hole 115 is preferably located in the middle of the branch points of adjacent radial flow paths 116 on the internal flow path. In the present invention, the lengths of the plurality of radial flow paths 116 may be set to be the same.

[0042] Although two side wall channels 128 are shown in the figure, it is of course understood that the present invention is not limited thereto. One side wall channel 128 or two or more side wall channels may be provided, and an appropriate number of communication holes for uniform inflow of purge gas may be provided.

[0043] On the other hand, in the present invention, although the side wall channel is shown as a one-dimensional channel extending in the axial direction of the shaft and having a predetermined length, the present invention is not limited thereto, and it goes without saying that it may be a two-dimensional cylindrical channel extending along the circumference of the side wall of the shaft.

[0044] The shaft may be joined to the plate. At this time, a ceramic binder or a ceramic paste may be used as the joining agent. In the present invention, the ceramic binder or the ceramic paste may be mainly composed of aluminum nitride, but is not limited thereto.

[0045] The flow path structure of the present invention described with reference to FIGS. 1, 2A, and 2B has the advantage that by dispersing the branch points at multiple locations in the internal flow path, structurally vulnerable parts inside the plate can be dispersed. In this way, it becomes possible to provide a purge gas flow path pattern that can suppress cracks generated during the pressure joining of the plate and the shaft by dispersing the flow path branch points of the purge gas.

[0046] At the same time, the branch structure has a radial structure that is symmetric with respect to the center of the plate, so that the purge gas can be ejected uniformly from the end of the plate.

[0047] In addition, the flow path structure of the present invention can provide a heat insulation mechanism that suppresses heat transfer to the shaft. This will be described with reference to FIG. 4.

[0048] (a) and (b) of FIG. 3 show internal flow paths 114 having different areas on the plate projection plane. In (a) and (b) of FIG. 3, the internal flow path 114 is located inside the contour of the connecting portion 122, but the width w1 of the internal flow path 114 may be adjusted.

[0049] If the width W1 of the internal flow path increases from (a) to (b) of FIG. 3, the flow path area intervening between the heating element layer 112 and the connecting portion 124 of the shaft increases. In the present invention, heat transfer by the flow path must depend on radiation or convection, and when compared with a plate body having high thermal conductivity, it can function as a heat insulating or heat shielding element. In particular, since heat loss to the shaft occurs through the joint portion between the shaft and the plate, that is, the shaft connecting portion, heat loss from the heating element layer can be suppressed by aligning the internal flow path with the shaft connecting portion.

[0050] In the present invention, the width w1 of the internal flow path may be designed to be smaller than the width w2 of the shaft connecting portion 124. In the present invention, the ratio of the internal flow path width w1 to the connecting portion width w2 may be 0.1 or more, 0.2 or more, 0.3 or more, 0.4 or more, or 0.5 or more. Also, the ratio of the internal flow path width w1 to the connecting portion width w2 may 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. Preferably, the ratio may be 0.1 to 0.7. Also, according to the present invention, by adjusting the width of the internal flow path, it becomes possible to prevent heat loss by the shaft or suppress crack generation. For example, if the ratio of the internal flow path width w1 to the connecting portion width w2 is less than 0.1, it is difficult to prevent heat loss, and if the ratio of the internal flow path width exceeds 0.7, cracks may occur.

[0051] On the other hand, although the drawings show an internal flow path arranged at the center of the contour of the connecting portion, the present invention is not limited to this. In the present invention, the internal flow path may be arranged relatively close to the center side of the plate inside the contour of the connecting portion, or conversely, may be arranged so as to be biased to the outside of the plate.

[0052] Figure 4 is a photograph for explaining the temperature change due to the shaft position in a conventional susceptor. After operating the susceptor of Figure 4 at a temperature of 650°C, Table 1 shows the temperatures measured at each point, circle 1, circle 2, circle 3, circle 4, and circle 5.

[0053]

Table 1

[0054] From Table 1, it can be seen that the vicinity of the mount is exposed to a high temperature of 300°C or more. Although the heat generated by the heater plate is transmitted through the shaft, the temperature becomes 300°C or more until it reaches the lower end region (circle 5) where the mount 130 is attached, and there is a problem that the O-ring sealing the mount melts. In serious cases, there is a problem that the vacuum in the chamber is released. To prevent this, the purge gas passing through the side wall flow path on the side wall of the shaft can be utilized as a cooling gas. That is, by forming a purge line along the periphery of the side wall at the lower end of the shaft, the heat transmitted to the mount can be reduced.

[0055] As described above, the present invention has been described with specific matters such as specific components, limited embodiments, and drawings, but this is only provided to assist in a more general understanding of the present invention. The present invention is not limited to the above embodiments, and those having ordinary knowledge in the field to which the present invention pertains can make various modifications and variations without departing from the essential characteristics of the present invention. Therefore, the idea of the present invention should not be defined only by the described embodiments, and not only the scope of the following claims, but also any technical ideas having modifications equivalent or equivalent to this scope of claims should be interpreted as being included in the scope of rights of the present invention.

Explanation of Reference Numerals

[0056] 110 Plate 112 Heating Element Layer 114 Internal Flow Path 115 Communication hole 116 Branch flow path 120 Shaft 122 Shaft side wall 124 Shaft connection part 128 Side wall flow path 130 Mount

Claims

1. A susceptor including a plate in which a heating element layer is embedded, and a hollow shaft joined to a lower end of the plate, The plate includes a purge gas flow path layer disposed on a different plane from the heating element layer, The purge gas flow path layer includes an inner flow path and a plurality of radial flow paths extending outward from the inner flow path.

2. The hollow shaft is The susceptor of claim 1 , further comprising a sidewall extending in a longitudinal direction and a connector at an end of the sidewall that forms a joint with the plate.

3. The susceptor of claim 2 , wherein the internal passage has a shape that corresponds to a coupling portion of the shaft.

4. The susceptor of claim 3 , wherein the internal passages and connections are circular.

5. The susceptor according to claim 3 , wherein on a plane onto which the plate is projected, the internal flow passage is disposed within an outline of the connecting portion.

6. The susceptor of claim 5 , wherein the internal passage is disposed relatively close to a center of the plate within a contour of the connector.

7. The susceptor according to claim 5, wherein a ratio of a width of the internal flow passage to a width of the connecting portion is 0.1 to 0.

7.

8. the shaft includes a sidewall passage extending within the sidewall along the length of the sidewall; The susceptor of claim 5 , wherein an end of the sidewall channel is aligned with the interior channel.

9. The susceptor of claim 8 , wherein an end of the sidewall channel is located on the interior channel at a midpoint between adjacent radial channels.

10. a mount coupled to an end of the shaft; a purge line along a sidewall of the shaft end; The susceptor of claim 8 , wherein the purge line is coupled to the sidewall channel.

11. the shaft includes a plurality of sidewall channels extending within the sidewall along the length of the sidewall; The susceptor of claim 5 , wherein each end of the plurality of sidewall channels is aligned with the interior channel.

12. The susceptor of claim 1 , wherein the plurality of radial channels are symmetrical about a center of the plate.

13. The susceptor according to claim 11, wherein the number of the plurality of radial channels is 4 to 10.

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