Heating device for chemical vapor deposition apparatus, vapor deposition apparatus and installation method

Abstract

A heating device for a chemical vapor deposition apparatus, a vapor deposition apparatus and an installation method. The heating device comprises a first heating component, a second heating component and a heat insulator, wherein the first heating component has a first end and a second end, both the first end and second end being connected to the heat insulator; and the second heating component is arranged at the periphery of the first heating component, the second heating component has two lead-out fixing ends, the two lead-out fixing ends being located on the same side and connected to the heat insulator, and the side of the second heating component away from the lead-out fixing ends abuts against the surface of the heat insulator by means of a supporting member. The second heating component is heated to radially expand towards the side away from the lead-out fixing ends, so that the first heating component and the expanded second heating component are concentric or coaxial. The heating device enables uniform temperature distribution within a temperature field, thereby effectively improving the uniformity of concentration and thickness of an epitaxial wafer.

Description

Heating device for chemical vapor deposition equipment, vapor deposition equipment and installation method Technical Field

[0001] The present application relates to the technical field of semiconductor equipment manufacturing, and in particular to a heating device for chemical vapor deposition equipment, chemical vapor deposition equipment, and an installation method. Background Art

[0002] Semiconductor CVD equipment, also known as chemical vapor deposition (CVD) equipment, is essential for producing high-quality semiconductor single-crystal thin films. These include silicon carbide epitaxial equipment, MOCVD, and PECVD. Silicon carbide epitaxial equipment and MOCVD equipment, in particular, are high-tech devices that integrate vacuum, high-temperature, and high-speed rotation technologies. The reaction principle is that a substrate is placed on a graphite tray and heated. Reactive gases flow over the surface of the substrate, heated to the reaction temperature, causing a chemical reaction to form a single-crystal thin film. Technical issues

[0003] Temperature has a significant impact on the concentration and thickness uniformity of epitaxial doping growth, so the design of the heating device is very important for thin film growth. However, in the existing technology, the heating device will expand when heated, resulting in an uneven temperature field at the bottom of the graphite tray, thereby affecting the concentration and thickness uniformity of the epitaxial wafer. Technical Solutions

[0004] In order to overcome the above-mentioned shortcomings, the purpose of this application is to provide a heating device for chemical vapor deposition equipment, a chemical vapor deposition equipment (CVD equipment) and an installation method, which can make the temperature field at the bottom of the graphite tray uniform, thereby ensuring uniform concentration and thickness of the grown epitaxial wafers.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] A heating device for chemical vapor deposition equipment, comprising:

[0007] thermal insulation;

[0008] a first heating component fixed to the thermal insulation member;

[0009] a second heating component, the second heating component being arranged on the periphery of the first heating component, the second heating component having two lead-out fixed ends, the two lead-out fixed ends being located on the same side and connected to the heat insulating member, a side of the second heating component away from the lead-out fixed end being in contact with the surface of the heat insulating member via a support member,

[0010] Wherein, when heated, the second heating component radially expands toward the side away from the lead-out fixed end, so that the first heating component and the expanded second heating component are concentric or coaxial. With such a design, the temperature field of the combination of the first heating component and the second heating component is uniform when the chemical vapor deposition equipment (also called epitaxial equipment) is in epitaxial growth, which is conducive to the growth of high-quality epitaxial wafers. The second heating component is arranged along the circumference of the first heating component (such as being sleeved on the first heating component and having a gap between it and the first heating component). When the second heating component is heated and expanded, the support member slides along the surface of the thermal insulation member, so that the first heating component and the expanded second heating component are concentric or coaxial. At room temperature / normal temperature, the first heating component and the second heating component are eccentrically arranged, and when in epitaxial growth, they are concentrically arranged, which facilitates the uniformity of the temperature field on the substrate side, which is conducive to the growth of high-quality epitaxial wafers (such as silicon carbide epitaxy).

[0011] Preferably, the second heating element is eccentrically positioned relative to the first heating element, with its center offset toward the side of the second heating element's fixed lead end. At room temperature, the second heating element is eccentrically positioned relative to the first heating element. This allows the second heating element to expand and become concentric or coaxial with the first heating element, thereby creating a uniform temperature field.

[0012] Furthermore, the distance between the center of the second heating component and the center of the first heating component is an eccentric distance a, and the eccentric distance is 1 mm≤a≤4 mm.

[0013] As a preferred embodiment, at least one guide groove adapted to the support member is radially extended from a side of the second heating component away from the lead-out fixed end.

[0014] Furthermore, a guide groove is provided, and an extension line of an axis of the guide groove and the centers of the first heating component and the second heating component are in a straight line.

[0015] Furthermore, two guide grooves are provided, and the two guide grooves are arranged opposite to the two lead-out fixed ends.

[0016] As a preferred embodiment, two second heating components are included, and the two second heating components are sleeved on the periphery of the first heating component.

[0017] As a preferred embodiment, the first heating component and the second heating component are both made of graphite.

[0018] The present application also provides a chemical vapor deposition device, including a reaction chamber, the bottom of the reaction chamber has a rotating support component, the rotating support component is provided with a tray for placing a substrate, and the rotating support component is provided with a heating device as described above, which is used to heat the substrate.

[0019] This application also provides a method for installing a heating device in a chemical vapor deposition apparatus, which is applicable to the above-mentioned chemical vapor deposition apparatus. The installation method comprises the following steps:

[0020] Determine the center position of the first heating component according to the center position of the tray and fix the first heating component.

[0021] Determine the positions of the two lead-out fixed ends on the second heating component according to the center position of the first heating component and fix the second heating component.

[0022] The position of the second heating component is determined and fixed by the positions of the two lead-out fixed ends.

[0023] When the second heating component is at room temperature, the distance between the center position between the two lead-out fixed ends and the center of the first heating component is the sum of the radius of the second heating component and half of the expansion amount of the second heating component in the diameter direction;

[0024] When the second heating element is heated, it expands away from the lead-out fixed end, causing the first and second heating elements to become concentric or coaxial. At room temperature, the first and second heating elements are eccentrically positioned. During epitaxial growth, they are concentrically positioned. This ensures a uniform temperature field on the substrate side, facilitating the growth of high-quality epitaxial wafers (such as silicon carbide epitaxial). Beneficial effects

[0025] In the present application, the second heating component is eccentrically arranged, and the two lead-out fixed ends of the second heating component are connected to the thermal insulation member and are located on the same side. As a result, after the second heating component is heated, the side of the second heating component away from the lead-out fixed end will expand radially, making the first heating component concentric or coaxial with the second heating component, and making the temperature distribution of the temperature field uniform, thereby effectively improving the uniformity of the concentration and thickness of the epitaxial wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are intended to facilitate understanding of the technical solutions of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solutions of the present disclosure and do not constitute a limitation of the technical solutions of the present disclosure. The shapes and sizes of the components in the accompanying drawings do not reflect the actual scale and are intended only to illustrate the contents of this application.

[0027] FIG1 is a schematic structural diagram of a chemical vapor deposition apparatus according to an embodiment of the present application;

[0028] Figure 2 is a schematic structural diagram of a heating device for chemical vapor deposition equipment according to an embodiment of the present application;

[0029] FIG3 is a schematic cross-sectional view of a heating device for chemical vapor deposition equipment according to an embodiment of the present application;

[0030] FIG4 is a top view of the second heating component in an initial state in an embodiment of the present application;

[0031] FIG5 is a top view of the second heating component in a heated state according to an embodiment of the present application;

[0032] FIG6 is a bottom view of the second heating component in the present application;

[0033] FIG7 is a bottom view of another embodiment of the second heating component in the present application;

[0034] FIG8 is a top view of another embodiment of a heating device for chemical vapor deposition equipment in the present application. DETAILED DESCRIPTION

[0035] The above scheme is further described below with reference to specific examples. It should be understood that these examples are intended to illustrate the present application and are not intended to limit the scope of the present application. The implementation conditions used in the examples can be further adjusted according to the conditions of the specific manufacturer. The implementation conditions not specified are generally those used in routine experiments.

[0036] Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should have the usual meanings understood by people with ordinary skills in the field to which this application belongs. The "first", "second" and similar words used in the embodiments of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. In this article, "electrical connection" includes the situation where constituent elements are connected together through an element with some electrical function. "Element with some electrical function" is not particularly limited as long as it can transfer electrical signals between connected constituent elements. "Element with some electrical function" can be, for example, an electrode or wiring, or a switching element such as a transistor, or other functional elements such as a resistor, inductor or capacitor. “Up,” “down,” “left,” “right,” etc. are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0037] In this application, terms such as "upper," "lower," "inner," and "middle" indicate positions or locations based on those shown in the accompanying drawings. These terms are primarily intended to better describe this application and its embodiments and are not intended to limit the devices, elements, or components indicated to specific positions, or to their construction or operation in a specific position.

[0038] The present application discloses a heating device for chemical vapor deposition equipment, a chemical vapor deposition equipment, and an installation method. The heating device includes a first heating component, at least one second heating component, and a thermal insulation member. The first heating component has a first end and a second end, each of which is connected to the thermal insulation member. The second heating component is disposed on the periphery of the first heating component and has two lead-out fixed ends, which are located on the same side and connected to the thermal insulation member. The side of the second heating component away from the lead-out fixed ends abuts against the surface of the thermal insulation member via a support member. When heated, the second heating component radially expands toward the side away from the lead-out fixed ends, making the first heating component and the expanded second heating component concentric or coaxial. The heating device uniformizes the temperature distribution of the temperature field, thereby effectively improving the uniformity of the concentration and thickness of the epitaxial wafer. The chemical vapor deposition equipment is an epitaxial device, such as a silicon carbide epitaxial device. Vapor deposition equipment is also called chemical vapor deposition equipment.

[0039] Next, the chemical vapor deposition apparatus proposed in this application will be described with reference to FIG. 1 .

[0040] The chemical vapor deposition equipment comprises:

[0041] The reaction chamber 100 has a rotating support component 200 at its bottom. A tray 210 for placing a substrate is disposed on the rotating support component 200. A heating device 300 is disposed in the rotating support component 200 for heating the substrate.

[0042] Next, the heating device for chemical vapor deposition equipment proposed in this application will be described with reference to FIG. 2 to FIG. 8 .

[0043] 2-3 , a heating device for chemical vapor deposition equipment includes:

[0044] Thermal insulation 10;

[0045] A first heating member 20 having a first end 21 and a second end 22 , wherein the first end 21 and the second end 22 are respectively connected to the thermal insulation member 10 ;

[0046] The second heating component 30 is arranged on the periphery of the first heating component 20. The second heating component 30 has two lead-out fixed ends 31. The two lead-out fixed ends 31 are located on the same side and connected to the thermal insulation member 10. The side of the second heating component 30 away from the lead-out fixed ends 31 abuts against the surface of the thermal insulation member 10 through a support member 32. The first heating component 20 and the second heating component 30 are respectively connected to an external power source and are separately controlled by it.

[0047] In response to heat, the second heating element 30 radially expands toward the side of the second heating element 30 away from the lead-out fixed end 31, causing the first heating element 20 and the expanded second heating element 30 to be concentric or coaxial. The first heating element 20 is fixed to the thermal insulation member 10. This design ensures a uniform temperature field on the substrate side during epitaxial growth in the chemical vapor deposition apparatus (also known as an epitaxial apparatus), facilitating the growth of high-quality epitaxial wafers. The second heating element 30 is positioned circumferentially around the first heating element 20 (e.g., positioned within the first heating element 20 with a gap between the first heating element 20 and the expanded second heating element 30). As the second heating element 30 expands due to heat, the support member 32 slides along the surface of the thermal insulation member 10, facilitating the concentricity or coaxiality between the first heating element 20 and the expanded second heating element 30. At room temperature, the first and second heating elements 20 and 30 are eccentrically positioned. During epitaxial growth, they are concentrically positioned. This ensures a uniform temperature field on the substrate side, facilitating the growth of high-quality epitaxial wafers (e.g., silicon carbide epitaxial wafers).

[0048] Specifically, the second heating component 30 and the first heating part 20 in the present application both include graphite material, mainly utilizing the fact that graphite will expand away after being heated at high temperature. After the second heating component 30 in the present application is powered on and heated, since the two lead-out fixed ends 31 of the second heating component 30 are connected to the thermal insulation component 10 and are located on the same side, the side of the second heating component 30 away from the lead-out fixed end 31 will expand radially.

[0049] 4 , when the second heating component 30 is in the initial state, the second heating component 30 is eccentrically arranged relative to the first heating component 20, and the center of the second heating component 30 is biased toward one side of the lead-out fixed end 31 of the second heating component 30. The distance from the center of the second heating component 30 to the center of the first heating component 20 is the eccentric distance a, and the eccentric distance is 1 mm ≤ a ≤ 4 mm.

[0050] 5 , when the second heating component 30 expands due to heat, during the process of heating the substrate, the two lead-out fixed ends 31 of the second heating component are fixed on the same side, and the side of the second heating component 30 away from the lead-out fixed end 31 expands radially, so that the first heating component 20 and the second heating component 30 are concentric or coaxial.

[0051] The following takes the second heating element made of graphite as an example to calculate the expansion of the second heating element made of graphite when heated.

[0052] The expansion amount of the second heating component is ΔL=2a (Formula 1). The formula for thermal expansion is shown in Formula 2:

[0053] △L=α×△T×L (Formula 2)

[0054] Wherein, △L represents the expansion amount of the second heating component, unit: mm; α represents the average thermal expansion coefficient, unit: mm / mm·K; △T represents the temperature difference, unit: K; L is the original diameter (length), unit: mm.

[0055] Taking the graphite second heating element used to heat a 6-inch substrate as an example, the expansion of the graphite second heating element from room temperature 293K to 2873K is △L=4.4×10 -6 × (2873-293) × 180 = 2.04 mm, the installation eccentricity difference between the inner and outer rings is a = 1 / 2△L = 1 mm.

[0056] The two lead-out fixed ends of the second heating component made of graphite are connected to the insulation member and are located on the same side. After being heated, the side of the second heating component away from the lead-out fixed end expands radially. When the substrate sheet is heated to the temperature required for the process, the temperature of the external heating device is about 2873K, the expansion amount is 2mm, and the center of the graphite second heating component coincides with the center of the first heating component when it moves 1mm. The graphite second heating component and the graphite first heating component form a concentric uniform temperature field (the temperature on the substrate side is uniform, and preferably, the temperature difference between the center of the substrate side and its edge is less than 2°C).

[0057] 1 and 6-7 , in this embodiment, the second heating component 30 has at least one guide groove 33 radially extending from one side away from the lead-out fixed end 31 and adapted to the support member 32 . The guide groove 33 is configured to ensure the concentricity of the second heating component 30 and the first heating component 20 after expansion.

[0058] 4-6 , in this embodiment, when the second heating component 30 is provided with a guide groove 33a, the axis of the guide groove 33a is on the same straight line as the center of the second heating component 30 and the center of the first heating component 20. Specifically, the extension line of the line connecting the center of the first heating component 20 and the center of the second heating component 30 is one of the diameter lines of the first heating component 20 or the second heating component 30. This design is conducive to improving the concentricity of the second heating component 30 and the first heating component 20 after expansion.

[0059] As a variation of the embodiment of Figure 6, as shown in Figure 7, when the second heating component 30 is provided with two guide grooves 33b, the two guide grooves 33b are respectively arranged opposite to the two lead-out fixed ends 31. This design is not only conducive to improving the concentricity of the second heating component 30 and the first heating component 20 after expansion, but also can ensure the circularity of the second heating component 30 after expansion.

[0060] Referring to Figure 8, in this embodiment, two second heating components 30 are included, and the two second heating components 30 are sleeved on the periphery of the first heating component 20. When the two second heating components 30 are in the initial state, the two second heating components 30 are eccentrically arranged relative to the first heating component 20. The distance from the center of the second heating component 30a close to the first heating component 20 to the center of the first heating component 20 is an eccentric distance a1, and the distance from the center of the second heating component 30b away from the first heating component 20 to the center of the first heating component 20 is an eccentric distance a2, a1>a2. Similarly, in order to better ensure the concentricity of the second heating component and the first heating component after expansion, a guide groove 33 compatible with the support member 32 is provided on the side of each second heating component 30 away from the lead-out fixed end 31.

[0061] With reference to FIG3 and in combination with FIG4-FIG5 , the present application further provides a method for installing a heating device in a chemical vapor deposition apparatus.

[0062] The installation method first determines the center position of the first heating component 20 by the center position of the tray. In this step, the first heating component 20 is fixed after the center position is determined.

[0063] Then, the positions of the two lead-out fixed ends 31 on the second heating component 30 are determined according to the center position of the first heating component 20. Finally, the position of the second heating component is determined by the positions of the two lead-out fixed ends 31. In this step, the second heating component is fixed after the positions of the two lead-out fixed ends 31 are determined. At room temperature, the second heating component is eccentrically arranged with respect to the first heating component.

[0064] When the second heating component is at room temperature, which specifically refers to 23°C-25°C, the distance between the center of the two lead-out fixed ends 31 and the center of the first heating component 20 is the sum of the radius of the second heating component 30 and half of the diameter expansion of the second heating component 30. One of the diameter lines of the second heating component 30 is the line connecting the center of the first heating component 20 and the center of the second heating component 30. The two lead-out fixed ends 31 are symmetrically arranged about the diameter line.

[0065] When the second heating member 30 is heated and expanded, the heating temperature range here can be between 1200°C and 2000°C (preferably between 1500°C and 1700°C), and the side of the second heating member 30 away from the lead-out fixed end 31 is heated and expanded, so that the first heating member 20 and the second heating member 30 are concentric or coaxial.

[0066] It can be understood that, as shown in FIG4 , the thermal expansion of the second heating member 30 can be regarded as the linear expansion of the diameter L of countless second heating members, and the expansion direction is shown by the arrow in the figure. Since one end of the second heating member 30 is a fixed end, the expansion amount of the side of the second heating member 30 close to the lead-out fixed end 31 is smaller than the expansion amount of the side away from the lead-out fixed end 31. However, according to Formula 2, the expansion amount of materials with equal length and uniform density and consistent temperature rise is the same. Therefore, the eccentric distance can be determined by the expansion amount, and then the position of the two lead-out fixed ends can be determined. The following is a calculation method for determining the position of the two lead-out fixed ends:

[0067] First, determine the expansion amount using Formula 2: △L=α×△T×L (Formula 2), then determine the eccentric distance using Formula 1: △L=2a (Formula 1), and finally determine the position of the two lead-out fixed ends based on the distance between the center position of the two lead-out fixed ends and the center of the first heating component being L / 2+a, thereby completing the installation of the second heating component. The diameter of the expanded second heating component is L+2a.

[0068] Specifically, two second heating components 30 are disposed around the first heating component 20 , and the second heating component 30 b away from the first heating component 20 is installed in the same manner as the second heating component 30 a close to the first heating component 20 .

[0069] The first heating member 20 and the second heating member 30 described in this application do not limit the detailed shapes of the first heating member 20 and the second heating member 30. In other embodiments, a third heating member may be further disposed outside the second heating member 30. During the epitaxial process, the first heating member 20, the second heating member 30, and the third heating member are coaxial or concentric after expansion.

[0070] The above embodiments are intended only to illustrate the technical concepts and features of this application. Their purpose is to enable those familiar with the art to understand the content of this application and implement it accordingly. They are not intended to limit the scope of protection of this application. Any equivalent changes or modifications made in accordance with the spirit of this application shall be included in the scope of protection of this application.

Claims

1. A heating device for chemical vapor deposition equipment, characterized in that: include: Thermal insulation; a first heating component, the first heating component being disposed on the thermal insulation member; a second heating component, the second heating component is arranged at the periphery of the first heating component, the second heating component has two lead-out fixed ends, the two lead-out fixed ends are located on the same side and connected to the thermal insulation component, the second heating component has a support member on a side away from the lead-out fixed ends, the support member abuts against the surface of the thermal insulation component, Wherein, the second heating component is heated to expand radially toward a side away from the lead-out fixed end, so that the first heating component and the expanded second heating component are concentric or coaxial.

2. The heating device for chemical vapor deposition equipment according to claim 1, characterized in that: The second heating component is eccentrically arranged relative to the first heating component, and the center of the second heating component is biased toward one side of the lead-out fixed end of the second heating component.

3. The heating device for chemical vapor deposition equipment according to claim 2, characterized in that: The distance from the center of the second heating component to the center of the first heating component is an eccentric distance a, and the eccentric distance is 1 mm≤a≤4 mm.

4. The heating device for chemical vapor deposition equipment according to claim 1, characterized in that: At least one guide groove matched with the support member is radially extended from a side of the second heating component away from the lead-out fixed end.

5. The heating device for chemical vapor deposition equipment according to claim 4, characterized in that: One guide groove is provided, and an extension line of an axis of the guide groove and the center of the first heating component and the center of the second heating component are on the same straight line.

6. The heating device for chemical vapor deposition equipment according to claim 4, characterized in that: Two guide grooves are provided, and the two guide grooves are arranged opposite to the two lead-out fixed ends.

7. The heating device for chemical vapor deposition equipment according to claim 1, characterized in that: It also includes two second heating components, which are sleeved on the periphery of the first heating component.

8. The heating device for chemical vapor deposition equipment according to claim 1, characterized in that: The first heating component has a first end and a second end, the first end and the second end are respectively connected to the thermal insulation component, and the first heating component and the second heating component both include graphite material.

9. A vapor deposition device, characterized in that: It comprises a reaction chamber, the bottom of which has a rotating support component, the rotating support component is provided with a tray for placing a substrate, the rotating support component is provided with a heating device as described in any one of claims 1-8, and the heating device is used to heat the substrate.

10. A method for installing a heating device in a chemical vapor deposition device, suitable for the vapor deposition device as claimed in claim 9, characterized in that: The installation method comprises the following steps: The center position of the first heating component is determined according to the center position of the tray. The positions of the two lead-out fixed ends of the second heating component are determined according to the center position of the first heating component. The position of the second heating component is determined and fixed by the positions of the two lead-out fixed ends. Wherein, when the second heating component is at room temperature, the distance between the center position of the two lead-out fixed ends and the center of the first heating component is the sum of the radius of the second heating component and one half of the expansion amount of the second heating component in the diameter direction, When the second heating component is heated, it expands toward the side away from the lead-out fixed end, so that the first heating component and the second heating component are concentric or coaxial.

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