Substrate epitaxial growth device, preheating ring and manufacturing method thereof

Abstract

The invention relates to a substrate epitaxial growth device, a preheating ring and a manufacturing method thereof, the substrate epitaxial growth device comprises a supporting seat used for bearing a substrate, the preheating ring is arranged around the circumferential direction of the supporting seat, and the preheating ring comprises a preheating body and a passivation film. When the reaction chamber is arranged in a substrate epitaxial growth device to work, reaction gas is preheated by the preheating ring in the process of entering the reaction chamber, and then a subsequent process is carried out; besides, a crystal film layer and a passive film connected to the crystal film layer are arranged on the outer surface of the main body, the material attribute of the crystal film layer is the same as the attribute of a single crystal material on the substrate, and the material attribute of the passive film of the preset ring is the same as the material attribute of the passive film on the substrate, so that the upper surface area of the substrate is expanded equivalently; in the epitaxial process, the pattern density effect can occur on the preheating ring instead of the substrate, the edge thickness uniformity of the epitaxial wafer is improved, and the product yield is improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of semiconductor equipment, and in particular to a substrate epitaxial growth device, a preheating ring and a manufacturing method thereof. Background Art

[0002] In the semiconductor manufacturing industry, chemical vapor deposition (CVD) is a well-known process for forming thin film materials on substrates (such as silicon wafers). In the CVD process, gaseous molecules of the material to be deposited are provided to the substrate to form a thin film of the material on the substrate through a chemical reaction. The formed thin film can be a polycrystalline film layer, an amorphous film layer or an epitaxial crystalline film layer. Among them, a covering and a single crystal material (specifically, for example, silicon or germanium) exposed outside the covering are provided on the substrate. Epitaxy is a technology for depositing a crystalline film layer (specifically, for example, a silicon germanium thin film layer) on a single crystal plane according to the single crystal crystal direction. The newly grown crystalline film layer is the epitaxial layer, and the substrate with the epitaxial layer is called an epitaxial wafer.

[0003] For epitaxial wafers, the quality requirements for the epitaxial layer are very high, and one of the key indicators is the uniformity control of the thickness of the epitaxial layer. In the process of producing epitaxial wafers by epitaxial process, the pattern density effect is a classic problem of epitaxial process, that is, the thickness uniformity of the epitaxial layer of the substrate is poor. The existence of the pattern density effect will lead to lower product quality. In related technologies, the pattern density effect is reduced by adjusting the temperature field and the flow field. Specifically, the pattern density effect is reduced by increasing the gas flow rate, but the process variation becomes larger, and the control requirements for the equipment are higher. Summary of the invention

[0004] Based on this, it is necessary to overcome the defects of the prior art and provide a substrate epitaxial growth device, a preheating ring and a manufacturing method thereof, which can effectively reduce the pattern density effect during the epitaxial process, improve the thickness uniformity of the epitaxial wafer edge, and achieve an increase in product yield.

[0005] A preheating ring is used to be arranged in a substrate epitaxial growth device, wherein the substrate epitaxial growth device comprises a support seat for carrying a substrate, and the preheating ring is arranged circumferentially around the support seat, wherein the preheating ring comprises:

[0006] A preheating body, wherein the preheating body is annular and comprises a main structure and a crystal film layer disposed on an outer surface of the main structure; and

[0007] A passivation film covers a portion of the upper surface of the preheating body and is arranged around the circumference of the preheating body, and another portion of the upper surface of the preheating body is exposed.

[0008] In one embodiment, the upper surface area of ​​the passivation film is set to S1, the upper surface area of ​​the crystal film layer is set to S, and 75%≦S1 / S≦99%.

[0009] In one of the embodiments, the upper surface of the preheating body is concave toward the lower surface of the preheating body to form at least one recess, and the passivation film is disposed in the recess.

[0010] In one embodiment, the recess is arranged at an inner side, a middle part, an outer side of the upper surface of the preheating body, or extends from an inner edge to an outer edge of the preheating body.

[0011] In one embodiment, the recess is provided in plurality, and the plurality of recesses are arranged in sequence around the central axis of the preheating body, and / or the plurality of recesses are arranged in sequence along the radial direction of the preheating body; or, the recess is provided in one and is arranged circumferentially around the preheating body; or, the upper surface of the passivation film is planar and flush with the surface of the exposed area of ​​the crystal film layer.

[0012] In one embodiment, the passivation film is provided in plurality, and the plurality of passivation films are arranged in sequence around the central axis of the preheating body, and / or the plurality of passivation films are arranged in sequence along the radial direction of the preheating body; or, the passivation film is provided in one and is arranged circumferentially around the preheating body.

[0013] In one of the embodiments, when the recess is arranged on the inner side of the upper surface of the preheating body, the inner edge of the passivation film and the inner edge of the preheating body are on the same plane; or, when the recess is arranged on the outer side of the upper surface of the preheating body, the outer edge of the passivation film and the outer edge of the preheating body are on the same plane.

[0014] In one of the embodiments, the passivation film is tightly fitted to the inner wall of the recess; and / or the passivation film is coated, electroplated or 3D printed in the recess.

[0015] In one embodiment, the main structure includes graphite, the crystalline film layer includes silicon carbide or graphite; and / or the passivation film is silicon oxide, silicon nitride or silicon oxynitride.

[0016] A substrate epitaxial growth device comprises the preheating ring, and also comprises: a reaction chamber and a support seat; the reaction chamber is provided with a gas injection port and a gas exhaust port, the support seat is arranged inside the reaction chamber and is used to carry the substrate, the preheating is arranged circumferentially around the support seat, a support member is provided on the side wall of the reaction chamber, and the support member is connected to the preheating ring.

[0017] In one embodiment, the upper surface of the support seat includes a first heated zone and a second heated zone arranged around the first heated zone; the substrate epitaxial growth device also includes an inner zone heating element and an outer zone heating element; the inner zone heating element is arranged opposite to the first heated zone and is used to heat the first heated zone, and the outer zone heating element is arranged opposite to the second heated zone and is used to heat the second heated zone.

[0018] In one embodiment, the inner zone heating element includes at least one first heating element arranged above the reaction chamber and at least one second heating element arranged below the reaction chamber; the outer zone heating element includes at least one third heating element arranged above the reaction chamber and at least one fourth heating element arranged below the reaction chamber.

[0019] In one embodiment, the first heating element is provided in plurality and is spaced in sequence around the central axis of the reaction chamber; the second heating element is provided in plurality and is spaced in sequence around the central axis of the reaction chamber; the third heating element is provided in plurality and is spaced in sequence around the central axis of the reaction chamber; the fourth heating element is provided in plurality and is spaced in sequence around the central axis of the reaction chamber.

[0020] A method for manufacturing the preheating ring comprises:

[0021] A surface perpendicular to the central axis of the preheating body is set as a reference surface, and the preheating body and the passivation film on the preheating body obtain a first projection area and a second projection area on the reference surface along the central axis; the area ratio of the first projection area to the second projection area is set to a first ratio, and the area ratio of the single crystal material on the substrate to the area ratio of the passivation film on the substrate is set to a second ratio; so that the deviation value of the first ratio and the second ratio is set within a preset range.

[0022] In one of the embodiments, the preset range of the deviation value is set to 0 to 10%; and / or the material of the passivation film of the preset ring is the same as the material of the passivation film on the substrate.

[0023] The above-mentioned substrate epitaxial growth device, preheating ring and manufacturing method thereof, when installed in the substrate epitaxial growth device for operation, the reaction gas is first preheated by the preheating ring in the process of entering the reaction chamber, and then the subsequent process is carried out; in addition, since a crystal film layer and a passivation film connected to the crystal film layer are provided on the outer surface of the main body, the material properties of the crystal film layer are the same as the properties of the single crystal material on the substrate, and the material properties of the passivation film of the preset ring are the same as the material properties of the passivation film on the substrate, which is equivalent to expanding the upper surface area of ​​the substrate (that is, the area where the film layer is deposited). During the epitaxial process, the pattern density effect can occur on the preheating ring instead of on the substrate, thereby improving the uniformity of the edge thickness of the epitaxial wafer and achieving an increase in product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic structural diagram of a preheating ring disposed on the periphery of a substrate according to an embodiment of the present application.

[0025] Figure 2 for Figure 1 Schematic diagram of the structure of the preheating ring in the structure shown.

[0026] Figure 3 for Figure 2 Cross-sectional view of an embodiment at AA.

[0027] Figure 4 for Figure 2 Cross-sectional view of another embodiment at AA.

[0028] Figure 5 for Figure 2 A cross-sectional view of yet another embodiment at AA.

[0029] Figure 6 for Figure 2 A cross-sectional view of yet another embodiment at AA.

[0030] Figure 7 for Figure 2 A cross-sectional view of yet another embodiment at AA.

[0031] Figure 8 This is a cross-sectional structural diagram of a preheating ring according to another embodiment of the present application.

[0032] Fig. 9 This is a cross-sectional structural diagram of a preheating ring according to another embodiment of the present application.

[0033] Fig.10 This is a cross-sectional structural diagram of a preheating ring according to another embodiment of the present application.

[0034] Fig.11 This is a top view of the preheating ring according to another embodiment of the present application.

[0035] Fig.12 This is a top view of the preheating ring according to another embodiment of the present application.

[0036] Fig.13 This is a top view of the preheating ring according to another embodiment of the present application.

[0037] Fig.14 It is a schematic structural diagram of a substrate epitaxial growth device according to an embodiment of the present application.

[0038] 10. Preheating ring; 11. Preheating body; 111. Main structure; 112. Crystal film layer; 113. Concave portion; 12. Passivation film; 20. Substrate; 21. Single crystal material; 22. Passivation film; 30. Support seat; 40. Reaction chamber; 41. Gas injection port; 42. Gas exhaust port; 51. First heating element; 52. Second heating element; 53. Third heating element; 54. Fourth heating element; 61. First high-temperature thermometer; 62. Second high-temperature thermometer. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0040] It should be noted that the substrate in this embodiment can be a semiconductor wafer at any stage in the process of forming semiconductor components on a substrate, such as an integrated circuit or discrete devices. In one embodiment, the substrate includes a very low dielectric constant dielectric layer and a metal layer on a semiconductor substrate. The substrate can be a mask, a semiconductor wafer, or other workpieces known to ordinary technicians in the field of electronic component manufacturing. In at least some embodiments, the substrate includes any material used to manufacture any integrated circuit, passive (e.g., capacitors, inductors) and active (e.g., transistors, light detectors, lasers, diodes) microelectronic components. The substrate can include insulating materials (e.g., dielectric materials) that separate such active and passive microelectronic components from one or more conductive layers formed on top of them. In one embodiment, the substrate is a semiconductor substrate including one or more dielectric layers, such as silicon, gallium nitride, gallium arsenide, silicon dioxide, silicon nitride, sapphire, and other dielectric materials. In one embodiment, the substrate is a wafer stack including one or more layers. The one or more layers of the wafer may include conductive layers, semiconductive layers, insulating layers, or any combination thereof.

[0041] As the background technology, the substrate in the related art has a pattern density effect during the epitaxial process and leads to a problem of reduced product quality. The inventors have found that the reason for this problem is that the covering material in the related art is usually silicon dioxide, silicon nitride or other heterogeneous materials. During the epitaxial process, the composition and proportion of the reaction gas are regulated so that the covering material does not react during the epitaxial process, that is, no film grows on the surface of the covering material. However, the pattern density effect generally occurs in the edge area of ​​the substrate, that is, the film thickness in the edge area of ​​the substrate is very thin, resulting in poor uniformity of film thickness.

[0042] Based on the above reasons, the present application provides a substrate epitaxial growth device, a preheating ring and a manufacturing method thereof, which can effectively reduce the pattern density effect during the epitaxial process, improve the process uniformity, and achieve a solution to improve product yield.

[0043] See also Figures 1 to 3 as well as Fig.14 , Figure 1 A schematic structural diagram of a preheating ring 10 arranged around the periphery of a substrate 20 according to an embodiment of the present application is shown. Figure 2 Shows Figure 1 A schematic structural diagram of the preheating ring 10 in the structure shown. Figure 3 Shows Figure 2 Cross-sectional view of an embodiment at AA. Fig.14 A schematic structural diagram of a substrate epitaxial growth device according to an embodiment of the present application is shown. A preheating ring 10 provided in an embodiment of the present application is used to be arranged in a substrate epitaxial growth device, and the substrate epitaxial growth device includes a support seat 30 for carrying a substrate 20. The preheating ring 10 is arranged around the circumference of the support seat 30, and the preheating ring 10 includes: a preheating body 11 and a passivation film 12. The preheating body 11 is annular, and the preheating body 11 includes a main structure 111 and a crystal film layer 112 arranged on the outer surface of the main structure 111. The passivation film 12 covers a part of the upper surface of the preheating body 11, and is arranged around the circumference of the preheating body 11, and another part of the upper surface of the preheating body 11 is exposed.

[0044] When the above-mentioned preheating ring 10 is installed in the substrate epitaxial growth device for operation, the reaction gas is first preheated by the preheating ring 10 in the process of entering the reaction chamber 40, and then the subsequent process is carried out; in addition, since a crystal film layer 112 and a passivation film 12 connected to the crystal film layer 112 are provided on the outer surface of the main body, the material properties of the crystal film layer 112 are the same as the properties of the single crystal material 21 on the substrate 20, and the material properties of the passivation film 12 of the preset ring are the same as the material properties of the passivation film 12 on the substrate 20, which is equivalent to expanding the upper surface area of ​​the substrate 20 (that is, the area where the film layer is deposited). During the epitaxial process, the pattern density effect can occur on the preheating ring 10 instead of on the substrate 20, thereby improving the uniformity of the thickness of the edge of the epitaxial wafer and achieving an increase in the product yield.

[0045] It should be noted that the upper surface of the preheating body 11 refers to the surface of the preheating body 11 facing the top wall of the reaction chamber 40 when the preheating ring 10 is installed in the substrate epitaxial growth device.

[0046] When the preset ring is installed in the substrate epitaxial growth device, the side of the preset ring where the passivation film 12 is located is arranged to face upward, that is, in the same direction as the upper surface of the substrate 20 .

[0047] In a specific embodiment, the specific material of the passivation film 12 of the preheating ring is the same as the specific material of the passivation film 22 on the substrate 20. In this way, after a lot of experimental studies, it is found that it is beneficial to make the pattern density effect occur on the preheating ring 10 instead of on the substrate 20.

[0048] In a specific embodiment, a surface perpendicular to the central axis of the preheating body 11 is set as a reference surface, and the preheating body 11 and the passivation film 12 on the preheating body 11 obtain a first projection area and a second projection area on the reference surface along the central axis, the first projection area corresponds to the exposed area of ​​the crystal film layer 112 (that is, the upper surface of the preheating body 11), and the second projection area corresponds to the passivation film 12. The area ratio of the first projection area to the second projection area is set to a first ratio, and the area ratio of the single crystal material 21 on the substrate 20 (that is, the exposed area of ​​the substrate 20) to the area ratio of the passivation film 22 on the substrate 20 is set to a second ratio. When the deviation value of the first ratio and the second ratio is set within a preset range, for example, within 10%, it is found through a large number of experimental studies that it is beneficial to make the pattern density effect occur on the preheating ring 10 instead of on the substrate 20.

[0049] In one embodiment, the deviation value includes but is not limited to 0%, 1%, 2%, 3%, 5%, 7%, 10%, etc., and can be flexibly adjusted and selected according to actual needs, which is not limited here. When the deviation value is smaller, it is more conducive to making the pattern density effect occur on the preheating ring 10 rather than on the substrate 20 during the epitaxial process, improving the uniformity of the thickness of the epitaxial wafer edge and achieving an increase in product yield.

[0050] Generally speaking, in the related art, the upper surface area of ​​the passivation film 22 on the substrate 20 (ie, the position where the film does not need to be grown in the epitaxial process) accounts for more than 90% of the entire upper surface area of ​​the substrate 20 .

[0051] It should be noted that the "crystal film layer 112" can be a part of the "main structure 111", that is, the "crystal film layer 112" and the "other parts of the main structure 111" are manufactured as one piece; it can also be an independent component separable from the "other parts of the main structure 111", that is, the "crystal film layer 112" can be manufactured independently and then combined with the "other parts of the main structure 111" into a whole.

[0052] In one embodiment, the upper surface area of ​​the passivation film 12 is set to S1, the upper surface area of ​​the crystal film layer 112 is set to S, and 75%≦S1 / S≦99%. In this way, the deviation between the first ratio and the second ratio can be made smaller, so that during the epitaxial process, the pattern density effect can be made to occur on the preheating ring 10 instead of on the substrate 20, which plays a role in improving the uniformity of the thickness of the epitaxial wafer edge and improving the product yield.

[0053] In some embodiments, the lower limit of S1 / S includes but is not limited to 75%, 80%, 85%, 90%, etc., and can also be any value less than 75% and greater than 90%, which can be flexibly adjusted and set according to actual needs.

[0054] In some embodiments, the upper limit value of S1 / S includes but is not limited to 90%, 92%, 93%, 95%, etc., and can also be any value less than 90% and greater than 95%, which can be flexibly adjusted and set according to actual needs.

[0055] See also Figures 3 to 10 As shown in any picture, Figures 4 to 10The cross-sectional structural diagrams of the preheating ring 10 of several other embodiments are shown. In one embodiment, the upper surface of the preheating body 11 is concave toward the lower surface of the preheating body 11 to form at least one recess 113. The passivation film 12 is arranged in the recess 113. In this way, the passivation film 12 can be firmly combined with the preheating body 11 and is not easy to fall off the preheating body 11; in addition, compared with directly setting the passivation film 12 on the preheating body 11 with a flat surface, when the passivation film 12 is set in the recess 113, the disturbance of the reaction gas entering the reaction chamber 40 is reduced, thereby improving stability.

[0056] It should be noted that the recess 113 can be set at any position on the upper surface of the preheating body 11, and the arrangement method is relatively flexible. It can be flexibly adjusted and set according to actual needs, and is not limited here.

[0057] In one embodiment, the recess 113 is arranged on the inner side of the upper surface of the preheating body 11 (see Figures 3 to 7 Any one shown), the middle part (please refer to Fig. 9 or Fig.10 ), the outer side (see Figure 8 ) or extends from the inner edge to the outer edge of the preheating body 11. In this way, when the recess 113 is arranged on the inner side of the preheating body 11 (such as Figures 3 to 7 As shown in any one of the drawings, the passivation film 12 is close to the substrate 20, and the exposed area of ​​the crystal film layer 112 is far away from the substrate 20, so that the part where the pattern density effect occurs on the preheating ring 10 is farther away from the substrate 20, which can be beneficial to improve the uniformity of the thickness of the edge of the epitaxial wafer and improve the product yield. In addition, when the recess 113 is arranged on the inner side or outer side of the preheating body 11, or the recess 113 extends from the inner edge to the outer edge of the preheating body 11, it is easier to machine the preheating body 11 than when the recess 113 is arranged in the middle. In addition, when the recess 113 is arranged on the inner side, middle part or outer side of the preheating body 11, the overall structural strength of the preheating body 11 is greater than when the recess 113 is extended from the inner edge to the outer edge of the preheating body 11, and it is not easy to break.

[0058] Please note that Figure 3 When the recess 113 is arranged at the inner side of the upper surface of the preheating body 11, the recess 113 starts from the inner edge of the upper surface of the preheating body 11 (i.e., the side facing the substrate 20) and extends toward the outer edge of the upper surface of the preheating body 11 (i.e., the side facing away from the substrate 20), and the extension length (corresponding to the width of the passivation film 12, as shown in FIG. Figure 3 ) is smaller than the distance between the inner edge of the preheating body 11 and the outer edge of the preheating body 11 (as shown in W1 in FIG. Figure 3The preheating body 11 is the thickness of the inner part (as shown in W2 in FIG. Figure 3 D1 in the figure) is smaller than the thickness of the outer part (as shown in Figure 3 The stepped structure is shown in D2 in FIG.

[0059] Otherwise, see Figure 8 When the recess 113 is arranged on the outer side of the upper surface of the preheating body 11, the recess 113 starts from the outer edge of the upper surface of the preheating body 11 (i.e., the side facing away from the substrate 20) and extends toward the inner edge of the upper surface of the preheating body 11 (i.e., the side facing the substrate 20), and the extension length (corresponding to the width of the passivation film 12, as shown in FIG. Figure 8 ) is smaller than the distance between the inner edge of the preheating body 11 and the outer edge of the preheating body 11 (as shown in W1 in FIG. Figure 8 The preheating body 11 is the thickness of the inner part (as shown in W2 in FIG. Figure 8 D1 in the figure) is greater than the thickness of the outer part (as shown in Figure 8 The stepped structure is shown in D2 in FIG.

[0060] Also, see Fig. 9 or Fig.10 When the recess 113 is arranged in the middle of the upper surface of the preheating body 11, that is, the opposite sides of the recess 113 are spaced from the inner edge and the outer edge of the upper surface of the preheating body 11, in other words, the recess 113 is in a groove shape. In this way, when the passivation film 12 is arranged inside the recess 113, the passivation film 12 is not easy to escape from the recess 113 and can be stably arranged inside the recess 113.

[0061] It should be noted that the number of the recesses 113 is not limited to one, and may be two, three, four, five, six or other numbers, and may be flexibly adjusted and set according to actual needs.

[0062] Among them, see Figure 2 and Figure 3 , when the number of the recesses 113 is set to one, that is, the recesses 113 are set as a whole and are arranged around the circumference of the preheating body 11. In this way, after the passivation film 12 is coated or electroplated inside the recesses 113, the passivation film 12 is a whole and is arranged around the circumference of the preheating body 11. In addition, since the passivation film 12 is arranged in the recesses 113, the number of the passivation film 12 is correspondingly set to one, and it is also set as a continuous whole and is arranged around the circumference of the preheating body 11.

[0063] In some other embodiments, see Figures 11 to 13In any picture, when the number of recesses 113 is set to be multiple, the multiple recesses 113 are sequentially arranged along the circumference of the preheating body 11 (as shown by the arrow f in the figure). In this way, the passivation film 12 is correspondingly set to be multiple and sequentially arranged along the circumference of the preheating body 11. Among them, the spacing between two adjacent recesses 113 in the circumferential direction of the preheating body 11, the equal spacing arrangement mode and the non-equal spacing arrangement mode of the recesses 113, and the number of arrangements of the recesses 113 can be flexibly adjusted according to the film thickness uniformity results of the actual product, so that the pattern density effect can be adjusted, the uniformity of the thickness of the epitaxial wafer edge can be improved, and the product yield can be improved.

[0064] In another embodiment, see Fig.10 When the number of the recesses 113 is set to be multiple, the multiple recesses 113 are arranged along the radial direction of the preheating body 11 (eg Fig.10 In addition, each concave portion 113 is set as a whole and arranged around the circumference of the preheating body 11. The size, arrangement number, and spacing between adjacent concave portions 113 can be adjusted based on the film thickness uniformity results of the actual product, so that the pattern density effect can be adjusted, the thickness uniformity of the epitaxial wafer edge can be improved, and the product yield can be improved. In addition, the passivation film 12 is correspondingly set in multiples and is arranged along the radial direction of the preheating body 11 (such as Fig.10 Set them in sequence as shown by the arrow Z in the figure.

[0065] In another embodiment, when the number of the recesses 113 is set to be multiple, the multiple recesses 113 are not limited to being arranged in sequence in the circumferential direction or in the radial direction of the preheating body 11 as in the above embodiment, but the multiple recesses 113 are arranged in a rectangular array or in other regular and irregular ways. In other words, multiple recesses 113 are sequentially arranged in the radial direction of the preheating body 11, and multiple recesses 113 are also sequentially arranged in the circumferential direction of the preheating body 11. Each recess 113 is correspondingly provided with a passivation film 12, and the arrangement of the recesses 113 corresponds to the arrangement of the passivation film 12 on the upper surface of the preheating body 11.

[0066] See also Figures 11 to 13 In some embodiments, when there are multiple recesses 113, the shapes and sizes of each recess 113 are flexibly adjusted and set according to actual needs, and can be the same as each other or different from each other, which is not limited here. The shapes of each recess 113 include but are not limited to regular shapes such as circles, ellipses, polygons, and irregular shapes. Correspondingly, the shape of the passivation film 12 includes but is not limited to regular shapes such as circles, ellipses, polygons, and irregular shapes.

[0067] See also Figure 3 In one embodiment, the upper surface of the passivation film 12 is flat and flush with the surface of the exposed area of ​​the crystal film layer 112. In this way, when the reaction gas flows through the upper surface of the preheating ring 10, the passivation film 12 will not block or interfere with the gas flow, thereby avoiding adverse effects on the uniformity of the film thickness on the surface of the substrate 20.

[0068] As some optional solutions, the passivation film 12 can also be completely disposed inside the recess 113, and the upper surface of the passivation film 12 can be flush with the surface of the exposed area of ​​the preheating body 11 (such as Figure 3 As shown), it can also be that the upper surface of the passivation film 12 is lower than the surface of the exposed area of ​​the preheating body 11 (as shown Figure 5 In addition, the passivation film 12 can also be embedded in the recess 113, that is, the upper surface of the passivation film 12 is higher than the surface of the exposed area of ​​the preheating body 11 (as shown). Figure 4 shown).

[0069] As some optional solutions, the upper surface of the passivation film 12 is not limited to being a plane (such as Figures 3 to 5 As shown), it can also be, for example, an inclined surface arranged at an angle to the surface of the exposed area of ​​the preheating body 11 (such as Figure 6 ), or it may be, for example, a curved surface (such as Figure 7 shown), curved surfaces, etc.

[0070] See also Figures 11 to 13 In one embodiment, the passivation film 12 is provided in plurality, and the plurality of passivation films 12 are sequentially arranged around the central axis of the preheating body 11, and / or the plurality of passivation films 12 are sequentially arranged along the radial direction of the preheating body 11; or, refer to Figure 2 The passivation film 12 is provided as one and is arranged around the circumference of the preheating body 11 .

[0071] See also Figure 3 In one embodiment, when the recess 113 is arranged on the inner side of the upper surface of the preheating body 11, the inner edge of the passivation film 12 is on the same plane as the inner edge of the preheating body 11. Alternatively, please refer to Figure 8 When the recess 113 is arranged at the outer side of the upper surface of the preheating body 11 , the outer edge of the passivation film 12 and the outer edge of the preheating body 11 are on the same plane.

[0072] See also Figures 3 to 10 In any of the figures, in one embodiment, the passivation film 12 is closely attached to the inner wall of the recess 113. In this way, there is no gap between the passivation film 12 and the inner wall of the recess 113, and the passivation film 12 and the preheating body 11 are closely combined with each other and are not easy to fall off.

[0073] See also Figures 3 to 10In any of the figures, in one embodiment, the passivation film 12 is closely attached to the inner wall of the recess 113 ; and / or, the passivation film 12 is coated, electroplated or 3D printed in the recess 113 .

[0074] See also Figure 3 In one embodiment, when the recess 113 is arranged at the inner side of the upper surface of the preheating body 11, the width of the passivation film 12 is set to W1, and W1 is 3 mm-20 mm.

[0075] After a large number of experiments, it was found that the pattern density effect in the related art causes the film thickness in the area within 5 mm from the edge of the substrate 20 to be relatively thin, resulting in poor uniformity of the film on the substrate 20 and low product yield. Based on this, W1 is optionally set to be greater than 5 mm. In this way, the pattern density effect can be effectively caused to occur on the preheating ring 10 instead of on the substrate 20, thereby improving the uniformity of the thickness of the epitaxial wafer edge and achieving an increase in product yield.

[0076] See also Figure 3 In one embodiment, the main structure 111 includes graphite; and / or the crystalline film layer 112 includes silicon carbide or graphite.

[0077] See also Figure 3 In one embodiment, the passivation film 12 is silicon oxide, silicon nitride or silicon oxynitride.

[0078] See also Figures 1 to 3 as well as Fig.14 In one embodiment, a substrate epitaxial growth device includes the preheating ring 10 of any of the above embodiments, and further includes: a reaction chamber 40 and a support seat 30. The reaction chamber 40 is provided with a gas injection port 41 and a gas exhaust port 42. The support seat 30 is arranged inside the reaction chamber 40 and is used to carry the substrate 20. The preheating ring 10 is arranged around the circumference of the support seat 30, and a support member is provided on the side wall of the reaction chamber 40, and the support member is connected to the preheating ring 10.

[0079] When the above-mentioned substrate epitaxial growth device is working, the reaction gas is first preheated by the preheating ring 10 when entering the reaction chamber 40, and then the subsequent process is carried out; in addition, since a crystal film layer 112 and a passivation film 12 connected to the crystal film layer 112 are provided on the outer surface of the main body, the material properties of the crystal film layer 112 are the same as the properties of the single crystal material 21 on the substrate 20, and the material properties of the passivation film 12 of the preset ring are the same as the material properties of the passivation film 22 on the substrate 20, which is equivalent to expanding the upper surface area of ​​the substrate 20 (that is, the area where the film layer is deposited). During the epitaxial process, the pattern density effect can occur on the preheating ring 10 instead of on the substrate 20, thereby improving the uniformity of the edge thickness of the epitaxial wafer and achieving an increase in product yield.

[0080] It should be noted that the "support member" can be "a part of the reaction chamber 40", that is, the "support member" and the "other parts of the reaction chamber 40" are manufactured in one piece; it can also be an independent component that can be separated from the "other parts of the reaction chamber 40", that is, the "support member" can be manufactured independently and then combined with the "other parts of the reaction chamber 40" into a whole.

[0081] See also Figure 4 In some embodiments, the reaction chamber 40 includes but is not limited to being a quartz chamber. In addition, the support base 30 includes but is not limited to being a silicon carbide, graphite or coated graphite base.

[0082] See also Figure 4 In one embodiment, the gas injection port 41 and the gas exhaust port 42 are located at two opposite sides of the reaction chamber 40 .

[0083] See also Figure 4 In some embodiments, the support seat 30 may be arranged horizontally, and the substrate 20 on the support seat 30 is placed horizontally accordingly. Optionally, the support seat 30 may be rotatable or stationary. During operation, the reaction gas enters the reaction chamber 40 through the gas injection port 41, first flows through the preheating ring 10, and the reaction gas is preheated by the preheating ring 10, and then a vapor deposition reaction is performed on the surface of the substrate 20 on the support seat 30, and then discharged to the outside through the gas outlet 42.

[0084] See also Figure 4 In one embodiment, the upper surface of the support seat 30 includes a first heated zone and a second heated zone arranged around the first heated zone. The substrate epitaxial growth device also includes an inner zone heater and an outer zone heater. The inner zone heater is arranged opposite to the first heated zone and is used to heat the first heated zone, and the outer zone heater is arranged opposite to the second heated zone and is used to heat the second heated zone. In this way, heating the upper surface of the support seat 30 in a zoned manner can more flexibly control the temperature of the substrate 20 and the reaction gas, which is beneficial to improving the uniformity of the thickness of the epitaxial wafer edge and achieving an increase in product yield.

[0085] Specifically, the area of ​​the first heating zone is, for example, 1 / 4-3 / 4 of the upper surface area of ​​the support base 30, and the area of ​​the second heating zone is, for example, 3 / 4-1 / 4 of the upper surface area of ​​the support base 30. The specific partitioning can be flexibly adjusted and set according to actual needs.

[0086] See also Figure 4 In some embodiments, the partitioning of the upper surface of the support seat 30 is not limited to the first heating zone and the second heating zone in the above embodiments, but can also be divided into three, four or more heating zones.

[0087] See also Figure 4 In one embodiment, the inner zone heating element includes at least one first heating element 51 arranged above the reaction chamber 40 and at least one second heating element 52 arranged below the reaction chamber 40. The outer zone heating element includes at least one third heating element 53 arranged above the reaction chamber 40 and at least one fourth heating element 54 arranged below the reaction chamber 40. In this way, the first heated zone is heated by the first heating element 51 located above the reaction chamber 40, and the first heated zone is heated by the second heating element 52 located below the reaction chamber 40, so that the first heated zone is heated evenly; in addition, the second heated zone is heated by the third heating element 53 located above the reaction chamber 40, and the second heated zone is heated by the fourth heating element 54 located below the reaction chamber 40, so that the second heated zone is heated evenly.

[0088] See also Fig.14 In one embodiment, the first heating element 51 is provided in a plurality and is sequentially spaced around the central axis of the reaction chamber 40. In addition, the second heating element 52 is provided in a plurality and is sequentially spaced around the central axis of the reaction chamber 40. In addition, the third heating element 53 is provided in a plurality and is sequentially spaced around the central axis of the reaction chamber 40. The fourth heating element 54 is provided in a plurality and is sequentially spaced around the central axis of the reaction chamber 40.

[0089] See also Fig.14 In some embodiments, the first heating element 51, the second heating element 52, the third heating element 53, and the fourth heating element 54 are each, but not limited to, an infrared heating lamp. The lengths and shapes of the infrared heating lamps can be the same or different from each other, and can be flexibly adjusted and set according to actual needs, wherein the shape can be straight, curved, etc.

[0090] See also Fig.14 In some embodiments, the substrate epitaxial growth device further includes a first high temperature thermometer 61, a second high temperature thermometer 62 and a controller. The first high temperature thermometer 61 is used to detect a first temperature of the upper surface of the substrate 20, and the second high temperature thermometer 62 is used to detect a second temperature of the lower surface of the substrate 20. The controller controls one of the first heating element 51, the second heating element 52, the third heating element 53 and the fourth heating element 54 to adjust the working power according to the first temperature and the second temperature.

[0091] See also Figures 1 to 3 as well as Fig.14In one embodiment, a method for manufacturing a preheating ring 10 of any of the above embodiments includes: setting a surface perpendicular to the central axis of the preheating body 11 as a reference surface, and obtaining a first projection area and a second projection area on the reference surface along the central axis of the preheating body 11 and the passivation film 12 on the preheating body 11, the first projection area corresponds to the exposed area of ​​the crystal film layer 112 (that is, the upper surface of the preheating body 11), and the second projection area corresponds to the passivation film 12.

[0092] The area ratio of the first projection area to the second projection area is set to a first ratio, and the area ratio of the single crystal material 21 on the substrate 20 (ie, the exposed area of ​​the substrate 20) to the area ratio of the passivation film 22 on the substrate 20 is set to a second ratio.

[0093] The deviation value between the first ratio and the second ratio is set within a preset range.

[0094] According to the manufacturing method of the above-mentioned preheating ring 10, when the reaction gas enters the reaction chamber 40, it is first preheated by the preheating ring 10 before the subsequent process is carried out; in addition, since a crystal film layer 112 and a passivation film 12 connected to the crystal film layer 112 are provided on the outer surface of the main body, the material properties of the crystal film layer 112 are the same as the properties of the single crystal material 21 on the substrate 20, and the material properties of the passivation film 12 of the preset ring are the same as the material properties of the passivation film 22 on the substrate 20, which is equivalent to expanding the upper surface area of ​​the substrate 20 (that is, the area where the film layer is deposited). During the epitaxial process, the pattern density effect can occur on the preheating ring 10 instead of on the substrate 20, thereby improving the uniformity of the edge thickness of the epitaxial wafer and achieving an increase in the product yield.

[0095] For example, when the value is set within 10%, it is found through a large number of experiments and studies that it is beneficial to make the pattern density effect occur on the preheating ring 10 rather than on the substrate 20.

[0096] In one embodiment, the preset range of the deviation value is set to 0 to 10%.

[0097] In one embodiment, the material of the passivation film 12 of the preset ring is the same as the material of the passivation film 22 on the substrate 20 .

[0098] It should be noted that silicon carbide (SiC) materials have various superior properties such as large bandgap, high breakdown electric field, large thermal conductivity, fast electron saturation drift rate, high chemical stability, and strong radiation resistance. They can be used as high-temperature resistant, high-frequency, radiation-resistant, and high-power semiconductor device materials and have broad application prospects.

[0099] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0100] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0101] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0102] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0103] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0104] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0105] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A preheating ring, used to be arranged in a substrate epitaxial growth device, wherein the substrate epitaxial growth device comprises a support seat for carrying a substrate, and the preheating ring is arranged around the circumference of the support seat, characterized in that: The preheating ring comprises: A preheating body, wherein the preheating body is annular and comprises a main structure and a crystal film layer disposed on an outer surface of the main structure; and A passivation film covers a portion of the upper surface of the preheating body and is arranged around the circumference of the preheating body, and another portion of the upper surface of the preheating body is exposed.

2. The preheating ring according to claim 1, characterized in that: The upper surface area of ​​the passivation film is set to S1, the upper surface area of ​​the crystal film layer is set to S, and 75%≦S1 / S≦99%.

3. The preheating ring according to claim 1, characterized in that: The upper surface of the preheating body is concave toward the lower surface of the preheating body to form at least one concave portion, and the passivation film is disposed in the concave portion.

4. The preheating ring according to claim 3, characterized in that: The recessed portion is arranged at an inner side, a middle part, an outer side of an upper surface of the preheating body, or extends from an inner edge to an outer edge of the preheating body.

5. The preheating ring according to claim 3 or 4, characterized in that: There are multiple recesses, which are arranged in sequence around the central axis of the preheating body, and / or, the recesses are arranged in sequence along the radial direction of the preheating body; or, there is one recess and it is arranged around the circumference of the preheating body; or, the upper surface of the passivation film is a plane and flush with the surface of the exposed area of ​​the crystal film layer.

6. The preheating ring according to claim 3 or 4, characterized in that: There are multiple passivation films, which are arranged in sequence around the central axis of the preheating body, and / or multiple passivation films are arranged in sequence along the radial direction of the preheating body; or, there is one passivation film and it is arranged around the circumference of the preheating body.

7. The preheating ring according to claim 3 or 4, characterized in that: When the recess is arranged on the inner side of the upper surface of the preheating body, the inner edge of the passivation film is on the same plane as the inner edge of the preheating body; or, when the recess is arranged on the outer side of the upper surface of the preheating body, the outer edge of the passivation film is on the same plane as the outer edge of the preheating body.

8. The preheating ring according to claim 4, characterized in that: The passivation film is tightly fitted to the inner wall of the recess; and / or the passivation film is coated, electroplated or 3D printed in the recess.

9. The preheating ring according to any one of claims 1 to 3, characterized in that: The main structure includes graphite, the crystal film layer includes silicon carbide or graphite; and / or the passivation film is silicon oxide, silicon nitride or silicon oxynitride.

10. A substrate epitaxial growth device, characterized in that: The substrate epitaxial growth device includes a preheating ring as described in any one of claims 1 to 9, and also includes: a reaction chamber and a support seat; the reaction chamber is provided with a gas injection port and a gas exhaust port, the support seat is arranged inside the reaction chamber and is used to support the substrate, the preheating is arranged circumferentially around the support seat, a support member is provided on the side wall of the reaction chamber, and the support member is connected to the preheating ring.

11. The substrate epitaxial growth device according to claim 10, characterized in that: The upper surface of the support seat includes a first heated zone and a second heated zone arranged around the first heated zone; the substrate epitaxial growth device also includes an inner zone heating element and an outer zone heating element; the inner zone heating element is arranged opposite to the first heated zone and is used to heat the first heated zone, and the outer zone heating element is arranged opposite to the second heated zone and is used to heat the second heated zone.

12. The substrate epitaxial growth device according to claim 11, characterized in that: The inner zone heating element includes at least one first heating element arranged above the reaction chamber and at least one second heating element arranged below the reaction chamber; the outer zone heating element includes at least one third heating element arranged above the reaction chamber and at least one fourth heating element arranged below the reaction chamber.

13. The substrate epitaxial growth device according to any one of claims 10 to 12, characterized in that: The first heating element is provided in plurality and is spaced in sequence around the central axis of the reaction chamber; the second heating element is provided in plurality and is spaced in sequence around the central axis of the reaction chamber; the third heating element is provided in plurality and is spaced in sequence around the central axis of the reaction chamber; the fourth heating element is provided in plurality and is spaced in sequence around the central axis of the reaction chamber.

14. A method for manufacturing a preheating ring according to any one of claims 1 to 13, characterized in that: include: A surface perpendicular to the central axis of the preheating body is set as a reference surface, and the preheating body and the passivation film on the preheating body obtain a first projection area and a second projection area on the reference surface along the central axis; the area ratio of the first projection area to the second projection area is set to a first ratio, and the area ratio of the single crystal material on the substrate to the area ratio of the passivation film on the substrate is set to a second ratio; so that the deviation value of the first ratio and the second ratio is set within a preset range.

15. The method for manufacturing a preheating ring according to claim 14, characterized in that: The preset range of the deviation value is set to 0 to 10%; and / or the material of the passivation film of the preset ring is the same as the material of the passivation film on the substrate.

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