Semiconductor epitaxy base and semiconductor epitaxy equipment

Abstract

The invention provides a semiconductor epitaxy base and semiconductor epitaxy equipment, and relates to the technical field of semiconductors. The method is used for reducing the edge temperature drop phenomenon, so that the film thickness uniformity and the resistivity uniformity are improved. The semiconductor epitaxial base comprises a supporting part and a main body part located on the supporting part. The main body part comprises a first main body section and a second main body section; the second main body section surrounds the first main body section and is connected with the first main body section; in the direction from the periphery of the main body part to the center line of the main body part, the thickness of the second main body section is sequentially increased, so that the outer edge of the second main body part forms a slope-shaped transition surface, and the transition surface can receive the radiation of a heat source, so that the temperature difference between the outer edge and the interior of the main body part is reduced, and the transfer of heat of a wafer from the middle to the periphery is reduced; therefore, the temperature difference between the middle part and the peripheral part of the wafer is reduced, the edge temperature drop phenomenon is improved, and the film thickness uniformity and the resistivity uniformity are further improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a semiconductor epitaxial base and a semiconductor epitaxial device. Background Art

[0002] Semiconductor epitaxy is the process of depositing a new single crystal layer on a wafer material such as silicon according to a process flow.

[0003] Usually, a base supporting the wafer is set in the cavity, and a high-temperature environment is provided by a light source such as a halogen lamp. Gaseous chemicals are introduced into the cavity, decomposed at high temperature and deposited on the wafer to form an epitaxial layer. Currently, the temperature uniformity of the wafer can be improved by adjusting the bulb power of the light source and optimizing the lamp head.

[0004] However, the above solution still cannot solve the problem of edge temperature drop, which affects the uniformity of film thickness and resistivity. Summary of the invention

[0005] The present application provides a semiconductor epitaxial base and a semiconductor epitaxial device, which are used to reduce the edge temperature drop phenomenon, thereby improving the uniformity of film thickness and resistivity.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] In one aspect, the present application provides a semiconductor epitaxial base, comprising a support portion and a main body portion located on the support portion;

[0008] The main body portion includes a first main body section and a second main body section, wherein the second main body section is disposed around the first main body section and connected to the first main body section;

[0009] The thickness of the second main body section increases gradually in a direction from the outer periphery of the main body portion toward the center line of the main body portion.

[0010] In a possible implementation, the second main body segment has a transition surface, and the transition surface connects the outer periphery of the main body portion and the lower surface of the main body portion.

[0011] In a possible implementation, the second main body segment has a transition surface, and the transition surface connects the outer periphery of the main body portion and the upper surface of the main body portion.

[0012] In a possible implementation, the shape of the transition surface is the same as the shape of the outer circumferential surface of the cone.

[0013] In a possible implementation, the transition surface is an arc surface.

[0014] In a possible implementation, the thickness of the second main body segment at the thinnest point is 0.5-2.5 mm, and the length of the second main body segment along the periphery of the main body toward the center line of the main body is 5-30 mm.

[0015] In a possible implementation manner, the upper surface of the main body has a groove, and the groove is used to place a wafer.

[0016] In a possible implementation, the support portion includes a connected support rod and a bracket;

[0017] The support rod is coaxially arranged with the main body;

[0018] The bracket includes a plurality of supporting legs, each of which is connected to the lower surface of the main body, and each of which is arranged at intervals along the circumferential direction of the main body.

[0019] On the other hand, the present application provides a semiconductor epitaxial device, comprising a cavity and any one of the semiconductor epitaxial bases described above, wherein the semiconductor epitaxial base is located in the cavity.

[0020] In a possible implementation, a preheating ring is provided in the cavity, and the preheating ring is arranged around the outer circumference of the main body.

[0021] The semiconductor epitaxial base and semiconductor epitaxial equipment provided by the present application have the following beneficial effects:

[0022] The semiconductor epitaxial base provided by the present application includes a support part and a main body part located on the support part, so that the main body part can carry a wafer. The main body part includes a first main body section and a second main body section, and the second main body section is wound around the first main body section and connected to the first main body section, and the thickness of the second main body section increases in the direction from the periphery of the main body section to the center line of the main body section, so that the outer edge of the second main body section forms a sloped transition surface, and the transition surface can receive radiation from a heat source, so that the temperature difference between the outer edge and the interior of the main body section is reduced, and the edge temperature drop phenomenon is reduced, thereby improving the film thickness uniformity and resistivity uniformity of the wafer after epitaxy.

[0023] In the related art, the outer peripheral surface of the base is a cylindrical surface, which is difficult to be radiated by the heat source, so that the temperature of the outer edge of the base is lower than the temperature of the middle part of the base. The chip is located on the base. Due to the low temperature of the outer edge of the base, under the action of heat diffusion, the heat of the chip is transferred from the middle to the periphery, so that the temperature of the outer edge of the chip is lower than the temperature of the middle part, resulting in a serious decrease in the edge temperature of the chip. In the present application, by setting the outer peripheral part of the base as a second main body section with a sloped transition surface, the thickness of the second main body section increases successively along the outer periphery of the main body toward the center, so that the outer peripheral part of the base, i.e., the second main body section, can receive the radiation of the heat source through the transition surface, thereby reducing the temperature difference between the outer edge of the base and the middle part of the base, and then reducing the temperature difference between the outer edge of the chip and the middle part of the chip, reducing the edge temperature drop phenomenon, and improving the film thickness uniformity and resistivity uniformity of the chip after epitaxy.

[0024] In addition to the technical problems solved by the present application, the technical features that constitute the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions described above, other technical problems that can be solved by the semiconductor epitaxial base and semiconductor epitaxial equipment provided by the present application, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further described in detail in the specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, a brief introduction will be given below to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A schematic diagram of the structure of a semiconductor epitaxial base provided for related technologies;

[0027] Figure 2 A schematic diagram of the structure of a semiconductor epitaxial device provided for related technologies;

[0028] Figure 3 A schematic structural diagram of a semiconductor epitaxial base provided in an embodiment of the present application;

[0029] Figure 4 for Figure 3 A partial schematic diagram of a semiconductor epitaxial base;

[0030] Figure 5 A partial schematic diagram of another semiconductor epitaxial base provided in an embodiment of the present application;

[0031] Figure 6A schematic diagram of the structure of a semiconductor epitaxial device provided in an embodiment of the present application;

[0032] Figure 7 for Figure 6 A partial enlarged view of area A.

[0033] Description of reference numerals:

[0034] 1-Semiconductor epitaxial base;

[0035] 2- Cavity;

[0036] 3- Preheating ring;

[0037] 4- Wafer;

[0038] 10- supporting part;

[0039] 11-support rod; 12-bracket; 121-support leg;

[0040] 20-main body;

[0041] 21-first main body section; 22-second main body section; 221-transition surface. DETAILED DESCRIPTION

[0042] In the related art, there is a technical problem that the edge temperature drops seriously, affecting the uniformity of film thickness and resistivity. The reason for this problem is that Figure 1 and Figure 2 The outer peripheral surface of the semiconductor epitaxial base 1 is a cylinder, which is difficult to be radiated by the heat source. Even if the power of the heat source bulb is adjusted or the lamp holder is optimized, the radiation received by the cylinder is limited, so that the temperature of the outer edge of the semiconductor epitaxial base 1 is lower than the temperature of the middle part of the semiconductor epitaxial base 1. The wafer 4 is located on the semiconductor epitaxial base 1. Since the temperature of the outer edge of the semiconductor epitaxial base 1 is low, under the effect of thermal diffusion, the heat of the wafer 4 is transferred from the middle to the periphery, so that the temperature of the outer edge of the wafer 4 is lower than the temperature of the middle part, resulting in a serious drop in the edge temperature of the wafer 4. Since the temperature of the outer edge of the wafer 4 is lower than the temperature of the middle part, the thickness difference between the outer edge and the middle part of the epitaxial layer of the wafer 4 during the growth process is large, resulting in poor uniformity of the film thickness of the wafer 4 after epitaxy, which in turn leads to poor uniformity of resistivity.

[0043] In response to the above technical problems, an embodiment of the present application provides a semiconductor epitaxial base and a semiconductor epitaxial device, in which a second main body section is wound around the first main body section and connected to the first main body section, and the thickness of the second main body section increases successively in the direction from the periphery of the main body section toward the center line of the main body section, so that the outer edge of the second main body section forms a sloped transition surface, and the transition surface can receive radiation from a heat source to reduce the temperature difference between the outer edge and the interior of the main body section, reduce the transfer of heat from the middle to the periphery of the chip, reduce the temperature difference between the middle and peripheral parts of the chip, improve the edge temperature drop phenomenon, and thereby improve the film thickness uniformity and resistivity uniformity.

[0044] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present application more obvious and understandable, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of this application.

[0045] The present application provides a semiconductor epitaxial base 1, such as Figure 3 As shown, the semiconductor epitaxial base 1 includes a support portion 10 and a main body 20. The main body 20 is connected to the support portion 10, the main body 20 is located on the support portion 10, the support portion 10 is a bearing structure of the main body 20, and the main body 20 is used to place or install the wafer 4.

[0046] refer to Figure 3 and Figure 4 The main body 20 includes a first main body section 21 and a second main body section 22, wherein the first main body section 21 is the middle part of the main body 20, and the first main body section 21 can be disc-shaped or approximately disc-shaped. The second main body section 22 is the edge part of the main body, and the second main body section 22 is arranged around the first main body section 21 and is connected to the first main body section 21. For example, the second main body section can be an annular structure, and the annular structure is arranged around the outer periphery of the first main body section 21. It should be noted that the first main body section 21 and the second main body section 22 can be an integrally formed structure.

[0047] refer to Figure 3 and Figure 4 The second main body section 22 is connected to the first main body section 21. The second main body section 22 is an annular structure, and the inner periphery of the annular structure is connected to the outer periphery of the first main body section 21. For example, the first main body section 21 and the second main body section 22 are an integrally formed structure. Figure 4 and Figure 5The thickness of the second main body section 22 increases in a direction from the outer periphery of the main body section 20 toward the center line of the main body section 20, or in a direction from the outer edge of the second main body section 22 toward the inner periphery of the second main body section, so that the outer edge of the second main body section 22 forms a sloped transition surface 221.

[0048] refer to Figure 4 The transition surface 221 can be the same or approximately the same shape as the outer peripheral surface of the truncated cone. The outer peripheral surface of the truncated cone is a continuous smooth curved surface formed by rotating the truncated cone generatrix around the central axis of the truncated cone. Figure 5 The transition surface 221 is a circular arc surface or a surface approximately similar to a circular arc surface. The transition surface 221 can reduce the temperature difference between the outer edge and the inner part of the main body 20, reduce the heat transfer from the middle to the periphery of the wafer 4, reduce the temperature difference between the middle part and the periphery of the wafer 4, improve the edge temperature drop, and thus improve the uniformity of film thickness and resistivity.

[0049] In the related art, the outer peripheral surface of the base is a cylindrical surface, which is difficult to receive the radiation of the heat source. Compared with the related art, the semiconductor epitaxial base provided by the present application is arranged around the first main body section 21 through the second main body section 22 and connected to the first main body section 21, and the thickness of the second main body section 22 increases in sequence along the outer periphery of the main body 20 toward the center line of the main body 20, so that the outer edge of the second main body 22 forms a sloped transition surface 221, and the transition surface 221 can receive the radiation of the heat source, so that the temperature difference between the outer edge and the inner part of the main body 20 is reduced, and the heat transfer of the wafer 4 from the middle to the periphery is reduced, so as to reduce the temperature difference between the middle part and the peripheral part of the wafer 4, improve the edge temperature drop phenomenon, and then improve the film thickness uniformity and resistivity uniformity.

[0050] In some embodiments, reference Figure 4 or Figure 5 The second main body section 22 has a transition surface 221, which connects the outer periphery of the main body 20 and the lower surface of the main body 20. In this embodiment, the transition surface 221 is a transition connection surface between the outer periphery of the main body 20 and the lower surface of the main body 20. One end of the transition surface 221 is connected to the outer periphery of the main body 20, and the other end of the transition surface 221 is connected to the lower surface of the main body 20. The heat source radiation located above the semiconductor base can be irradiated onto the transition surface 221, thereby reducing the temperature difference between the outer edge and the inner part of the main body 20, reducing the heat transfer of the wafer 4 from the middle to the periphery, reducing the temperature difference between the middle part and the outer periphery of the wafer 4, improving the edge temperature drop phenomenon, and thus improving the film thickness uniformity and resistivity uniformity.

[0051] In other embodiments, the second main body section 22 has a transition surface 221, and the transition surface 221 connects the outer periphery of the main body 20 and the upper surface of the main body 20. In this embodiment, the transition surface 221 is a transition connection surface between the outer periphery of the main body 20 and the upper surface of the main body 20, one end of the transition surface 221 is connected to the outer periphery of the main body 20, and the other end of the transition surface 221 is connected to the upper surface of the main body 20. The heat source radiation below the semiconductor base can be irradiated onto the transition surface 221, thereby reducing the temperature difference between the outer edge and the inner part of the main body 20, reducing the heat transfer of the wafer 4 from the middle to the periphery, reducing the temperature difference between the middle part and the outer periphery of the wafer 4, improving the edge temperature drop phenomenon, and thereby improving the film thickness uniformity and resistivity uniformity.

[0052] It should be noted that, in a possible implementation, the second main body 22 has two transition surfaces 221, one of which is a transition connection surface between the periphery of the main body 20 and the lower surface of the main body 20, and the other transition surface 221 is a transition connection surface between the periphery of the main body 20 and the upper surface of the main body 20. This allows the heat source radiation above the semiconductor base to irradiate one transition surface 221, and the heat source radiation below the semiconductor base to irradiate the other transition surface 221. This reduces the temperature difference between the outer edge and the inside of the main body 20, reduces the heat transfer of the wafer 4 from the middle to the periphery, reduces the temperature difference between the middle and peripheral parts of the wafer 4, improves the edge temperature drop phenomenon, and thus improves the film thickness uniformity and resistivity uniformity.

[0053] In some embodiments, reference Figure 4 or Figure 5 The thickness of the second main body section 22 at the thinnest part is 0.5-2.5 mm, for example, the thickness of the second main body section 22 at the thinnest part is 0.5 mm, 1 mm, 1.5 mm, 2 mm or 2.5 mm. Since the thickness of the second main body section 22 increases in a direction from the periphery of the main body 20 toward the center line of the main body 20, the thinnest part of the second main body section 22 is located at the outer edge of the main body 20, and the thickness at the outer edge of the main body 20 is 0.5-2.5 mm.

[0054] The length of the second main body section 22 is 5-30 mm, for example, 5 mm, 15 mm, 25 mm or 30 mm, along the outer periphery of the main body 20 toward the center line of the main body 20. In this way, the formed transition surface 221 can receive sufficient heat source radiation, further reducing the temperature difference between the outer edge and the inner part of the main body 20, and improving the edge temperature drop phenomenon.

[0055] In some embodiments, reference Figure 4The upper surface of the main body 20 has a groove, and the groove is used to place the wafer 4, for example, to install or hold the wafer 4. The wafer 4 is placed in the groove, for example, the wafer 4 is attached to the bottom of the groove. The groove can be a circular groove, a substantially circular groove, a square groove, or a substantially square groove, specifically matching the shape of the wafer 4, so as to facilitate the placement of the wafer 4.

[0056] In some embodiments, reference Figure 3 The support part 10 includes a support rod 11 and a bracket 12, the bracket 12 is connected to the support rod 11, and the bracket 12 is installed on the support rod 11. The bracket 12 includes a plurality of support legs 121, and the number of the support legs 121 can be two, three, four or more. Figure 3 Each support leg 121 abuts against the lower surface of the main body 20 and is connected to the main body 20 , such as by threaded connection, clamping connection or integral molding, so that the main body 20 can rotate with the bracket 12 .

[0057] The support rod 11 is coaxially arranged with the main body 20. The support rod 11 can be a cylindrical rod or a square rod, preferably a cylindrical rod, so that the support rod 11 can rotate, thereby driving the bracket 12 and the main body 20 installed on the bracket 12 to rotate along the axial direction of the support rod 11, thereby facilitating the uniformity of the thin film deposited on the wafer 4.

[0058] The present application also provides a semiconductor epitaxial device, referring to Figure 6 and Figure 7 The semiconductor epitaxial base 1 includes any one of the above embodiments and a cavity 2 , wherein the cavity 2 has a chamber, and the semiconductor epitaxial base 1 is located in the chamber in the cavity 2 .

[0059] The specific structure and related effects of the semiconductor epitaxial base 1 can refer to the related description of the above embodiments. Since the semiconductor epitaxial device adopts all the technical solutions of any of the above embodiments, it has at least all the beneficial effects brought by any of the above embodiments, which will not be described one by one here.

[0060] In some embodiments, reference Figure 6 and Figure 7 The semiconductor epitaxial device further includes a preheating ring 3, which is located in the cavity 2. The preheating ring 3 is arranged at the periphery of the main body 20 for heat exchange. Preferably, the preheating ring 3 is arranged coaxially with the main body 20, and the preheating ring 3 is used to absorb the heat of the heat source and radiate it near the edge of the main body 20 to further reduce the temperature difference between the outer edge and the inner part of the main body 20, reduce the heat transfer of the wafer 4 from the middle to the periphery, reduce the temperature difference between the middle part and the peripheral part of the wafer 4, improve the edge temperature drop phenomenon, and then improve the uniformity of film thickness and resistivity.

[0061] The various embodiments or implementation methods in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referenced to each other.

[0062] It should be noted that the embodiments indicated by "in specific implementation", "in some embodiments", "in this embodiment", "exemplarily" and the like mentioned in the specification may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, such phrases do not necessarily refer to the same embodiment. In addition, when describing specific features, structures or characteristics in conjunction with an embodiment, it is within the knowledge of those skilled in the art to implement such features, structures or characteristics in conjunction with other embodiments that are explicitly or not explicitly described.

[0063] In general, terms should be understood, at least in part, by the context in which they are used. For example, the term "one or more" as used herein may be used to describe any feature, structure, or characteristic in a singular sense, or may be used to describe a combination of features, structures, or characteristics in a plural sense, depending, at least in part, on the context. Similarly, terms such as "a" or "" may also be understood to convey singular usage or to convey plural usage, depending, at least in part, on the context.

[0064] It should be easily understood that “on,” “above,” and “over” in the present disclosure should be interpreted in the broadest manner, so that “on” not only means “directly on something,” but also includes the meaning of “on something” with intervening features or layers therebetween, and “above” or “over” not only includes the meaning of “above” or “over,” but also may include the meaning of “above” or “over something” with no intervening features or layers therebetween (i.e., directly on something).

[0065] In addition, spatially relative terms, such as "below," "below," "beneath," "above," "above," etc., may be used herein for ease of description to describe the relationship of one element or feature relative to other elements or features as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation shown in the figures. The device may have other orientations (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein may likewise be interpreted accordingly.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application 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 application.

Claims

1. A semiconductor epitaxial base, characterized in that: It comprises a support portion (10) and a main body portion (20) located on the support portion (10); The main body portion (20) comprises a first main body section (21) and a second main body section (22), wherein the second main body section (22) is arranged around the first main body section (21) and is connected to the first main body section (21); The thickness of the second main body section (22) increases gradually in a direction from the outer periphery of the main body portion (20) toward the center line of the main body portion (20).

2. The semiconductor epitaxial base according to claim 1, characterized in that: The second main body section (22) has a transition surface (221), and the transition surface (221) connects the outer periphery of the main body portion (20) and the lower surface of the main body portion (20).

3. The semiconductor epitaxial base according to claim 1, characterized in that: The second main body section (22) has a transition surface (221), and the transition surface (221) connects the outer periphery of the main body portion (20) and the upper surface of the main body portion (20).

4. The semiconductor epitaxial base according to claim 2 or 3, characterized in that: The shape of the transition surface (221) is the same as the shape of the outer peripheral surface of the truncated cone.

5. The semiconductor epitaxial base according to claim 2 or 3, characterized in that: The transition surface (221) is an arc surface.

6. The semiconductor epitaxial base according to any one of claims 1 to 3, characterized in that: The thickness of the second main body section (22) at the thinnest point is 0.5-2.5 mm, and the length of the second main body section (22) in the direction along the periphery of the main body (20) toward the center line of the main body (20) is 5-30 mm.

7. The semiconductor epitaxial base according to any one of claims 1 to 3, characterized in that: The upper surface of the main body (20) has a groove, and the groove is used to place the wafer (4).

8. The semiconductor epitaxial base according to any one of claims 1 to 3, characterized in that: The support portion (10) comprises a connected support rod (11) and a bracket (12); The support rod (11) is coaxially arranged with the main body (20); The bracket (12) comprises a plurality of supporting legs (121), each of the supporting legs (121) is connected to the lower surface of the main body (20), and each of the supporting legs (121) is arranged at intervals along the circumferential direction of the main body (20).

9. A semiconductor epitaxial device, characterized in that: It comprises a cavity (2) and a semiconductor epitaxial base as claimed in any one of claims 1 to 8, wherein the semiconductor epitaxial base is located in the cavity (2).

10. The semiconductor epitaxial device according to claim 9, characterized in that: It also comprises a preheating ring (3), wherein the preheating ring (3) is located in the cavity (2), and the preheating ring (3) is arranged around the outer periphery of the main body (20).

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