Thin film deposition reaction chamber and thin film deposition equipment

Abstract

The present invention discloses a thin film deposition reaction chamber and a thin film deposition device. An annular convex structure or an annular concave structure is arranged at the edge of a heating plate bearing region. In this way, the concave structure or the convex structure can be arranged at the edge of the heating plate bearing region according to whether the distribution intensity of plasma is greater at the center or the edge of a wafer during the thin film deposition process. The distance between the edge of the bearing region and a shower plate is thereby reduced or increased, and the quality of the thin film deposited at the edge of the wafer is changed, thereby ensuring the uniformity of the film quality at the center and edge of the wafer.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor process technology, and in particular to a thin film deposition reaction chamber and a thin film deposition device. Background Art

[0002] Plasma-Enhanced Atomic Layer Deposition (PEALD) is a technology that uses plasma to deposit metal or semiconductor materials in the form of atomic layers on the surface of a wafer to form a thin film.

[0003] At present, the reaction chamber used for depositing thin films usually has a shower plate as the upper electrode plate, a heating plate carrying the wafer and acting as the lower electrode plate, and radio frequency is applied to form plasma from the reaction gas sprayed from the shower plate to participate in the deposition reaction to form a thin film.

[0004] However, the area of ​​the current heating plate usually used to support the wafer is flat, and the plasma distribution intensity is different at the edge and center of the heating plate, which directly affects the quality of the deposited film, that is, the quality of the film at the center and edge of the wafer surface is different and not uniform enough. Summary of the invention

[0005] The object of the present invention is to provide a thin film deposition reaction chamber and a thin film deposition device, which can reduce or increase the distribution intensity of plasma at the edge of the supporting area, thereby changing the quality of the thin film deposited at the edge of the wafer, thereby ensuring the uniformity of the film quality at the center and edge of the wafer.

[0006] In the first aspect, the present invention provides a thin film deposition reaction chamber, comprising a chamber body and a spray plate and a heating plate located in the chamber, the spray plate and the heating plate being opposite to each other and spaced apart, the side of the heating plate facing the spray plate having a bearing area adapted to the size of a wafer, the edge portion of the bearing area being provided with an annular convex structure or an annular concave structure, the inner edge of the convex structure being farther away from the spray plate than the outer edge, and the inner edge of the concave structure being closer to the spray plate than the outer edge.

[0007] In an optional embodiment, the protruding structure or the recessed structure has a stepped structure.

[0008] In an optional embodiment, the step structure has 1-5 step layers.

[0009] In an optional embodiment, when the number of step layers of the step structure is 2 or more, the ratio of the height of one of two adjacent steps to the height of the other step is 1.1-2.

[0010] In an optional embodiment, when the number of step layers of the step structure is 2 or more, the ratio of the radius of one of two adjacent step layers to the radius of the other step layer is 1.05-1.5.

[0011] In an optional embodiment, the outer radius of the protruding structure is the same as the radius of the wafer.

[0012] In an optional embodiment, the outer radius of the recessed structure is the same as the radius of the wafer.

[0013] In an optional embodiment, a vertical distance between a portion of the protruding structure closest to the shower plate and a middle portion of the bearing area is H1, wherein 0

[0014] In an optional embodiment, a vertical distance between a portion of the recessed structure that is far from the shower plate and a middle portion of the bearing area is H2, wherein 0<H2≤20 mm.

[0015] In a second aspect, the present invention provides a thin film deposition device, comprising the thin film deposition reaction chamber described in any one of the aforementioned embodiments.

[0016] The beneficial effects of the embodiments of the present invention include:

[0017] By providing an annular raised structure at the edge portion of the bearing area of ​​the heating plate, the portion of the heating plate where the raised structure is provided will be closer to the shower plate than the central portion. Since both the shower plate and the heating plate are charged bodies, the electric field strength at the edge portion of the bearing area will be greater than that at the central portion, thereby increasing the distribution intensity of the plasma between the edge portion of the bearing area and the shower plate, thereby increasing the film quality at the edge portion of the wafer, and making the film quality at the central and edge portions of the wafer uniform. In other words, an annular recessed structure is provided at the edge portion of the bearing area of ​​the heating plate, so that the recessed structure is farther away from the shower plate than the central portion of the bearing area, thereby making the electric field strength at the edge portion of the bearing area smaller than that at the central portion, thereby reducing the distribution intensity of the plasma between the edge portion of the bearing area and the shower plate, thereby reducing the film quality at the edge portion of the wafer, and making the film quality at the central and edge portions of the wafer uniform. In summary, depending on whether the plasma distribution intensity is greater in the center or edge of the wafer during the thin film deposition process, a concave structure or a convex structure can be set at the edge of the heating plate's supporting area, so that the distance from the edge of the supporting area to the shower plate can be reduced or increased accordingly, thereby changing the quality of the deposited film at the edge of the wafer, thereby ensuring the uniformity of the film quality in the center and edge of the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] ​In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 is a schematic diagram of a thin film deposition reaction chamber;

[0020] Figure 2 Schematic diagram of the heating plate structure one of this embodiment;

[0021] Figure 3 This is a schematic diagram of the second structural form of the heating plate of this embodiment;

[0022] Figure 4 This is a schematic diagram of the step height dimensions of the heating plate structure type 1 of this embodiment;

[0023] Figure 5 This is a schematic diagram of the step height dimensions of the heating plate structure type 2 of this embodiment;

[0024] Figure 6 This is a schematic diagram of the step radius size of the heating plate structure type 1 of this embodiment;

[0025] Figure 7 It is a schematic diagram of the step radius size of the heating plate structure type 2 of this embodiment.

[0026] Icons: 10-heating plate; 11-convex structure; 12-concave structure; 20-spray plate; 30-wafer; 40-cavity. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0030] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0031] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0032] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] The following is combined with Figures 1 to 7 , some embodiments of the present invention are described in detail. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0034] Please refer to Figure 1 A thin film deposition reaction chamber includes a chamber 40 and a spray plate 20 and a heating plate 10 located in the chamber 40. The spray plate 20 and the heating plate 10 are arranged opposite to each other and at an interval. The heating plate 10 is located directly below the spray plate 20. The spray plate 20 is used as the external reaction gas to enter and then evenly transport the reaction gas to the heating plate 10. The side of the heating plate 10 facing the spray plate 20 has a bearing area adapted to the size of a wafer 30. The bearing area is mainly used to bear the wafer 30. At the same time, the heating plate 10 electrostatically adsorbs the wafer 30 to keep the wafer 30 fixed on the heating plate 10.

[0035] It should be noted that in the prior art, continue to refer to Figure 1 The upper surface bearing area of ​​the heating plate 10 is usually flat, but in the present embodiment, an annular protrusion structure 11 or an annular recessed structure 12 is provided at the edge of the bearing area, the inner edge of the protrusion structure 11 is farther away from the spray plate 20 than the outer edge, and the inner edge of the recessed structure 12 is closer to the spray plate 20 than the outer edge.

[0036] In this embodiment, by setting the edge portion of the bearing area of ​​the heating plate 10 as follows Figure 2 The annular protrusion structure 11 is shown, so that the portion of the heating plate 10 provided with the protrusion structure 11 will be closer to the shower plate 20 than the central portion. Since the shower plate 20 and the heating plate 10 are both charged bodies, the electric field strength of the edge portion of the bearing area will be greater than that of the central region, thereby improving the distribution intensity of the plasma between the edge portion of the bearing area and the shower plate 20, thereby improving the film quality of the edge portion of the wafer 30, and making the film quality of the central portion and the edge portion of the wafer 30 uniform; in other words, as Figure 3 As shown, an annular recessed structure 12 is provided at the edge of the bearing area of ​​the heating plate 10, so that the recessed structure 12 is farther from the shower plate 20 than the center of the bearing area, so that the electric field strength of the edge of the bearing area is smaller than that of the center, thereby reducing the distribution intensity of the plasma between the edge of the bearing area and the shower plate 20, and further reducing the film quality of the edge of the wafer 30, so that the film quality of the center and edge of the wafer 30 is uniform. In summary, the recessed structure 12 or the raised structure 11 can be provided at the edge of the bearing area of ​​the heating plate 10 according to whether the distribution intensity of the plasma is greater at the center or the edge of the wafer 30 during the film deposition process, so that the distance between the edge of the bearing area and the shower plate 20 is reduced or increased accordingly. The distribution intensity of the plasma at the edge of the bearing area is changed, thereby changing the quality of the deposited film at the edge of the wafer 30, and ensuring the uniformity of the film quality at the center and edge of the wafer 30.

[0037] In this embodiment, the diameter D of the wafer 30 is approximately 300 mm, and the protruding structure 11 or the recessed structure 12 both have a step structure with 1-5 steps, that is, for the protruding structure 11, the outer edge radius of the step away from the spray plate 20 of the two adjacent steps is equal to the inner radius of the step close to the spray plate 20, and for the recessed structure 12, the outer edge radius of the step of the two adjacent steps close to the spray plate 20 is equal to the inner edge radius of the step away from the spray plate 20.

[0038] Of course, in some embodiments, the protruding structure 11 or the recessed structure 12 may also be a frustum structure. In this case, the surface of the protruding structure 11 presents an annular conical surface, similar to a funnel shape, and the radius of the wafer 30 is greater than or equal to the radius of the outer edge of the protruding structure 11; the surface of the recessed structure 12 also presents an annular conical surface, similar to a horn shape, and the radius of the wafer 30 is greater than or equal to the radius of the recessed structure 12.

[0039] In this embodiment, when the number of step layers of the corresponding step structure is 2 or more, the ratio of the height of one of two adjacent steps to the height of the other step is 1.1-2.

[0040] Specifically, combined Figure 4 As the protrusion structure 11, the height of the step far from the spray plate 20 in the two adjacent steps is h1, and the height of the step close to the spray plate 20 is h2. Of course, the height of the step close to the spray plate 20 in the two adjacent steps can also be h1, and the height of the step far from the spray plate 20 is h2. As long as the height of one step in the two adjacent steps is h1, the height of the other step is h2. Figure 5 , as the concave structure 12, that is, the height of the step close to the shower plate 20 of the two adjacent steps is h1, and the height of the step away from the shower plate 20 is h2; of course, the height of the step away from the shower plate 20 of the two adjacent steps can also be h1, and the height of the step close to the shower plate 20 is h2. As long as the height of one step of the two adjacent steps is h1, the height of the other step is h2. Among them, the ratio of h2 / h1 is 1.1-2.

[0041] In addition, when the number of step layers of the step structure is 2 or more, the ratio of the radius of one of two adjacent step layers to the radius of the other step layer is 1.05-1.5.

[0042] Specifically, combined Figure 6 , as the protrusion structure 11, that is, the radius of the step close to the spray plate 20 of the two adjacent steps is r1, and the radius of the step away from the spray plate 20 is r2; of course, the radius of the step away from the spray plate 20 of the two adjacent steps can also be r1, and the radius of the step close to the spray plate 20 is r2; as long as the radius of one step of the two adjacent steps is r1, the radius of the other step is r2. Figure 7, as the concave structure 12, that is, the radius of the step far from the shower plate 20 of the two adjacent steps is r1, and the radius of the step close to the shower plate 20 is r2. Of course, the radius of the step close to the shower plate 20 of the two adjacent steps can also be r1, and the radius of the step far from the shower plate 20 is r2, as long as the radius of one step of the two adjacent steps is r1, and the radius of the other step is r2. Among them, the value range of r1 / r2 is 1.05-1.5.

[0043] Of course, in order to ensure that the area where the plasma distribution is enhanced between the protruding structure 11 and the shower plate 20 corresponds exactly to the edge portion of the wafer 30, the outer radius of the protruding structure 11 is set to be the same as the radius of the wafer 30, that is, the outer radius of the highest step is the same as the radius of the wafer 30.

[0044] Similarly, in order to ensure that the area where the plasma distribution is reduced between the recessed structure 12 and the shower plate 20 corresponds exactly to the edge portion of the wafer 30, the outer radius of the recessed structure 12 is set to be the same as the radius of the wafer 30, that is, the outer radius of the lowest step is the same as the radius of the wafer 30.

[0045] Continue to refer Figure 4 In order to increase the application range of the heating plate 10 with the protruding structure 11, the vertical distance between the part of the protruding structure 11 closest to the spray plate 20 and the middle part of the bearing area is H1, that is, the vertical distance between the upper surface of the highest step of the protruding structure 11 and the upper surface of the central part of the bearing area of ​​the heating plate 10 is H1, where 0

[0046] Similarly, continue to refer to Figure 5 In order to increase the application range of the heating plate 10 with the recessed structure 12, the vertical distance between the part of the recessed structure 12 far from the spray plate 20 and the middle part of the bearing area is H2, that is, the vertical distance between the upper surface of the lowest step of the recessed structure 12 and the upper surface of the central part of the bearing area of ​​the heating plate 10 is H2, where 0<H2≤20mm.

[0047] In addition, an embodiment of the present invention further discloses a thin film deposition device, which includes the thin film deposition reaction chamber of the above embodiment, and thus also has corresponding beneficial effects.

[0048] ​In summary, the embodiments of the present invention disclose a thin film deposition reaction chamber and a thin film deposition device. According to whether the distribution intensity of plasma is greater in the center or edge of the wafer 30 during the thin film deposition process, a recessed structure 12 or a raised structure 11 can be set at the edge of the bearing area of ​​the heating plate 10. The distance between the edge of the bearing area and the shower plate 20 can be reduced or increased accordingly, thereby changing the quality of the deposited thin film at the edge of the wafer 30, thereby ensuring the uniformity of the film quality at the center and edge of the wafer 30.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A thin film deposition reaction chamber, characterized in that: The invention comprises a cavity (40) and a spray plate (20) and a heating plate (10) located in the cavity (40), wherein the spray plate (20) and the heating plate (10) are arranged opposite to each other and spaced apart, and a side of the heating plate (10) facing the spray plate (20) has a bearing area adapted to the size of a wafer (30), and an annular protruding structure (11) or an annular concave structure (12) is arranged at an edge of the bearing area, wherein the inner edge of the protruding structure (11) is further away from the spray plate (20) than the outer edge, and the inner edge of the concave structure (12) is closer to the spray plate (20) than the outer edge; Wherein, when a wafer (30) is placed in the carrying area, the protruding structure (11) or the recessed structure (12) is located directly below the edge of the wafer (30).

2. The thin film deposition reaction chamber according to claim 1, characterized in that: The convex structure (11) or the concave structure (12) is in a stepped structure.

3. The thin film deposition reaction chamber according to claim 2, characterized in that: The step structure has 1-5 step layers.

4. The thin film deposition reaction chamber according to claim 2, characterized in that: When the number of steps of the step structure is 2 or more, the ratio of the height of one of two adjacent steps to the height of the other step is 1.1-2.

5. The thin film deposition reaction chamber according to claim 2, characterized in that: When the number of step layers of the step structure is 2 or more, the ratio of the radius of one of two adjacent step layers to the radius of the other step layer is 1.05-1.

5.

6. The thin film deposition reaction chamber according to claim 1, characterized in that: The outer radius of the protruding structure (11) is the same as the radius of the wafer (30).

7. The thin film deposition reaction chamber according to claim 1, characterized in that: The outer radius of the recessed structure (12) is the same as the radius of the wafer (30).

8. The thin film deposition reaction chamber according to claim 1, characterized in that: The vertical distance between the portion of the protruding structure (11) closest to the spray plate (20) and the middle portion of the bearing area is H1, where 0<H1≤20 mm.

9. The thin film deposition reaction chamber according to claim 1, characterized in that: The vertical distance between the portion of the recessed structure (12) far from the spray plate (20) and the middle portion of the bearing area is H2, wherein 0<H2≤20 mm.

10. A thin film deposition device, characterized in that: It comprises the thin film deposition reaction chamber as described in any one of claims 1 to 9.

Images