Silicon wafer heating assembly and silicon wafer epitaxial furnace

Abstract

The invention provides a silicon wafer heating assembly and a silicon wafer epitaxial furnace, and relates to the technical field of semiconductors, the silicon wafer heating assembly comprises a plurality of internal heating lamp groups, internal heating lamps of the internal heating lamp groups are used for heating a central area of a silicon wafer in a radial direction; external heating lamps of the external heating lamp groups are used for heating the edge area of the silicon wafer in the radial direction; the multiple internal heating lamp sets comprise the first internal heating lamp set and the second internal heating lamp set, and the linear distance between two internal heating lamps in the first internal heating lamp set is larger than the linear distance between two internal heating lamps in the second internal heating lamp set. The multiple external heating lamp sets comprise the first external heating lamp set and the second external heating lamp set, and the linear distance between two external heating lamps in the first external heating lamp set is smaller than the linear distance between two external heating lamps in the second external heating lamp set. According to the invention, the uniformity of the temperature for heating the surface of the silicon wafer is improved, so that the uniformity of the epitaxial resistivity is optimized.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, in particular to a silicon wafer heating component and a silicon wafer epitaxial furnace. Background Art

[0002] The epitaxial growth process of silicon wafers is an important process in the manufacture of semiconductor chips. This process refers to growing a layer of silicon single crystal layer with controllable resistivity and thickness, no crystal native particle defects and no oxygen precipitation on the polished silicon wafer under certain conditions. The most widely used method in the epitaxial growth process of silicon wafers is the vapor phase epitaxial deposition growth method. In this method, under a high temperature environment, silicon source gas and hydrogen react to generate single crystal silicon and deposit it on the surface of the silicon wafer to obtain an epitaxial layer. At the same time, dopants (such as B2H6, PH3) are introduced to dope the epitaxial layer to obtain a certain resistivity. This resistivity is an important indicator of the quality of silicon wafers, and its uniformity needs to be guaranteed within a certain range.

[0003] Generally speaking, resistivity is mainly affected by temperature. For example, for a P-type silicon wafer with a dopant of B2H6, the higher the temperature, the lower the resistivity, and the lower the temperature, the higher the resistivity. When the epitaxial growth process is carried out through an existing silicon wafer epitaxial furnace, the halogen lamp in the reaction chamber of the epitaxial furnace provides heat for the reaction by thermal radiation to the edge and center of the silicon wafer respectively. However, due to the uneven temperature radiation, the manufactured silicon wafer still has the problem of resistivity uniformity not meeting the requirements, especially the difference between the resistivity uniformity at half the radius of the silicon wafer exceeds 3% (the overall uniformity of the silicon wafer is 2.74%), and its uniformity is very poor. Summary of the invention

[0004] The embodiment of the present invention provides a silicon wafer heating assembly and a silicon wafer epitaxial furnace, which are used to solve the problem of poor resistivity uniformity of silicon wafers manufactured by epitaxial growth process using an epitaxial furnace in the prior art.

[0005] To solve the above technical problems, the embodiments of the present invention provide the following technical solutions:

[0006] An embodiment of the present invention provides a silicon wafer heating assembly, which is used to heat a silicon wafer in a silicon wafer epitaxial growth furnace;

[0007] The silicon wafer heating assembly comprises:

[0008] A plurality of internal heating lamp groups, each internal heating lamp group comprising two internal heating lamps arranged opposite to each other, the internal heating lamps being used to heat the central area of ​​the silicon wafer in the radial direction;

[0009] A plurality of external heating lamp groups, each of which includes two external heating lamps arranged opposite to each other, and the external heating lamps are used to heat the edge area of ​​the silicon wafer in the radial direction;

[0010] The inner heating lamps and the outer heating lamps are arranged in a preset order to form a circumferentially arranged ring, the line connecting the two inner heating lamps in each group of the inner heating lamps is the diameter of the ring, and the line connecting the two outer heating lamps in each group of the outer heating lamps is the diameter of the ring;

[0011] Wherein, the plurality of internal heating lamp groups include a first internal heating lamp group and a second internal heating lamp group, and a straight-line distance between two internal heating lamps in the first internal heating lamp group is greater than a straight-line distance between two internal heating lamps in the second internal heating lamp group;

[0012] The plurality of external heating lamp groups include a first external heating lamp group and a second external heating lamp group, wherein a straight-line distance between two external heating lamps in the first external heating lamp group is smaller than a straight-line distance between two external heating lamps in the second external heating lamp group.

[0013] In some embodiments, the plurality of internal heating lamp groups include at least two first internal heating lamp groups;

[0014] A line connecting two inner heating lamps in the first inner heating lamp group is a first diameter of the ring;

[0015] The first diameters corresponding to two of the first inner heating lamp groups are perpendicular to each other.

[0016] In some embodiments, the plurality of external heating lamp groups include at least two first external heating lamp groups;

[0017] A line connecting two external heating lamps in the first external heating lamp group is a second diameter of the ring;

[0018] The second diameters corresponding to two of the first external heating lamp groups are perpendicular to each other.

[0019] In some embodiments, the distance between the inner heating lamps in the first inner heating lamp group and the center of the ring is 152 mm-158 mm;

[0020] The distance between the inner heating lamps in the second inner heating lamp group and the center of the ring is 147mm-151mm.

[0021] In some embodiments, the distance between the external heating lamps in the first external heating lamp group and the center of the ring is 142 mm-147 mm;

[0022] The distance between the external heating lamps in the second external heating lamp group and the center of the ring is 148 mm-153 mm.

[0023] In some embodiments, an outer heating lamp is provided for every other inner heating lamp or every two adjacent inner heating lamps.

[0024] In some embodiments, the silicon wafer heating assembly further comprises: an internal reflection plate;

[0025] The inner reflection plate is located between the inner heating lamp and the silicon wafer;

[0026] The heat radiation of the inner heating lamp is reflected by the inner reflection plate to the central area of ​​the silicon wafer in the radial direction.

[0027] In some embodiments, the silicon wafer heating assembly further includes: an outer reflection plate;

[0028] The outer reflection plate is located between the outer heating lamp and the silicon wafer;

[0029] The heat radiation of the external heating lamp is reflected by the external reflection plate to the edge area of ​​the silicon wafer in the radial direction.

[0030] In some embodiments, the silicon wafer heating assembly further comprises: a lamp holder bracket formed in a ring shape, a heating lamp holder is arranged on the lamp holder bracket, and the heating lamp holder is used to support the inner heating lamp and the outer heating lamp.

[0031] An embodiment of the present invention further provides a silicon wafer epitaxial furnace, comprising a susceptor, a susceptor support frame and two silicon wafer heating assemblies as described in any one of the above;

[0032] Wherein, the base support frame is arranged below the base, the base support frame is used to support the base, and the base is used to carry the silicon wafer;

[0033] A silicon wafer heating assembly is disposed above the silicon wafer and is used to heat the upper surface of the silicon wafer;

[0034] Another silicon wafer heating component is disposed below the silicon wafer and is used for heating the lower surface of the silicon wafer.

[0035] The embodiments of the present invention have the following beneficial effects:

[0036] The silicon wafer heating assembly for heating silicon wafers in a silicon wafer epitaxial furnace provided in an embodiment of the present invention can achieve a higher temperature being applied to a half radius (R / 2) region of the silicon wafer by setting the distances between the internal heating lamps in different internal heating lamp groups to different values, i.e., increasing the straight-line distance between the two internal heating lamps in the first internal heating lamp group, and reducing the straight-line distance between the two external heating lamps in the first external heating lamp group. This can improve the uniformity of the temperature heated to the surface of the silicon wafer, thereby optimizing the uniformity of the epitaxial resistivity and improving the problem of poor resistivity uniformity of the epitaxial wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 One of the schematic diagrams showing the distribution of the resistivity of the epitaxial layer of the silicon wafer provided by the present invention;

[0038] Figure 2 A schematic diagram showing the structure of a silicon wafer heating assembly provided by the present invention;

[0039] Figure 3 The second schematic diagram showing the resistivity distribution of the epitaxial layer of the silicon wafer provided by the present invention. DETAILED DESCRIPTION

[0040] In order to make the technical problems, technical solutions and advantages to be solved by the embodiments of the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0041] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0042] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one", "one" or "the" do not indicate quantity restrictions, but indicate that there is at least one. Similar words such as "include" or "comprise" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Similar words such as "connect" or "connected" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0043] Before describing in detail the silicon wafer heating assembly and silicon wafer epitaxial furnace provided by the embodiments of the present disclosure, the following description is made:

[0044] In the prior art, a silicon wafer epitaxial growth device (or a silicon wafer epitaxial furnace) may include a base, a base support frame, and a silicon wafer heating assembly, wherein the base support frame is supported underneath the base, and the silicon wafer is carried on the base. When the epitaxial layer grows, the base and the base support frame can be rotated to improve the uniformity of the epitaxial layer growth on the surface of the silicon wafer.

[0045] During the epitaxial growth process, when the silicon wafer is heated by the existing silicon wafer heating assembly, due to the influence of the heating position of the halogen lamp in the silicon wafer heating assembly, there is still a certain temperature uneven area at half the radius (R / 2) of the silicon wafer. The temperature distribution of the wafer will have an important impact on the resistivity uniformity. The temperature unevenness leads to poor resistivity uniformity of the silicon wafer epitaxial layer. Figure 1 FIG. 1 illustrates the resistivity distribution of the epitaxial layer of a silicon wafer processed by an existing epitaxial growth device. Different color levels represent different resistivities of the epitaxial layer, with red representing low resistivity and blue representing high resistivity. Figure 1 It can be seen that the resistivity of the epitaxial layer has obvious different color levels and poor uniformity.

[0046] In order to solve the problem of poor resistivity uniformity of silicon wafers manufactured by epitaxial growth process using an epitaxial furnace in the prior art, an embodiment of the present invention provides a silicon wafer heating assembly and a silicon wafer epitaxial furnace.

[0047] like Figure 2 As shown, an embodiment of the present invention provides a silicon wafer heating assembly, which is used to heat a silicon wafer in a silicon wafer epitaxial growth furnace;

[0048] The silicon wafer heating assembly comprises: a plurality of internal heating lamp groups and a plurality of external heating lamp groups;

[0049] Each group of inner heating lamps includes two inner heating lamps arranged opposite to each other, and the inner heating lamps are used to heat the central area of ​​the silicon wafer in the radial direction;

[0050] Each group of external heating lamps includes two external heating lamps arranged opposite to each other, and the external heating lamps are used to heat the edge area of ​​the silicon wafer in the radial direction;

[0051] Among them, the central area of ​​the silicon wafer in the radial direction can be understood as the area between half the radius of the silicon wafer and the center of the silicon wafer, and the edge area of ​​the silicon wafer in the radial direction can be understood as the area between half the radius of the silicon wafer and the edge of the silicon wafer.

[0052] The inner heating lamps and the outer heating lamps are arranged in a preset order to form a circumferentially arranged ring, and the line connecting the two inner heating lamps in each group of the inner heating lamps is the diameter of the ring, and the line connecting the two outer heating lamps in each group of the outer heating lamps is the diameter of the ring. Figure 2As shown, the heating lamp corresponding to "IN" is an inner heating lamp, and the two inner heating lamps at the two ends of the diameter of the ring are an inner heating lamp group; the heating lamp corresponding to "OUT" is an outer heating lamp, and the two outer heating lamps at the two ends of the diameter of the ring are an outer heating lamp group.

[0053] In this embodiment, the heating lamps (including the inner heating lamp and the outer heating lamp) are halogen lamps.

[0054] For example, Figure 2 As shown, a silicon wafer heating assembly includes 32 heating lamps, of which there are 10 internal heating lamp groups with 20 internal heating lamps, and there are 6 external heating lamp groups with 12 external heating lamps.

[0055] Wherein, the multiple groups of internal heating lamps include a first internal heating lamp group and a second internal heating lamp group, and the straight-line distance between two of the internal heating lamps in the first internal heating lamp group is greater than the straight-line distance between two of the internal heating lamps in the second internal heating lamp group.

[0056] It should be noted that since the resistivity of the epitaxial layer of the silicon wafer is mainly related to the heating temperature. When the radiation direction of the internal heating lamps is the same, by setting the straight-line distance between the two internal heating lamps of different internal heating lamp groups to different values, heating of different positions in the central area of ​​the silicon wafer can be achieved. Specifically, the straight-line distance between the two internal heating lamps in the first internal heating lamp group is increased and set to be greater than the straight-line distance between the two internal heating lamps in the second internal heating lamp group. This can achieve that the internal heating lamps in the first internal heating lamp group and the second internal heating lamp group radiate different positions in the central area of ​​the silicon wafer. The radiation range of the two internal heating lamps in the first internal heating lamp group is closer to the half radius of the silicon wafer, so that a higher temperature can be applied to the R / 2 area of ​​the silicon wafer.

[0057] Optionally, the number of the first internal heating lamp group is at least one, and the number of the second internal heating lamp group is at least one.

[0058] The plurality of external heating lamp groups include a first external heating lamp group and a second external heating lamp group, wherein a straight-line distance between two external heating lamps in the first external heating lamp group is smaller than a straight-line distance between two external heating lamps in the second external heating lamp group.

[0059] It should be noted that since the resistivity of the epitaxial layer of the silicon wafer is mainly related to the heating temperature. When the radiation direction of the external heating lamps is the same, by setting the straight-line distance between the two external heating lamps of different external heating lamp groups to different values, heating of different positions in the edge area of ​​the silicon wafer can be achieved. Specifically, the straight-line distance between the two external heating lamps in the first external heating lamp group is reduced and set to be smaller than the straight-line distance between the two external heating lamps in the second external heating lamp group. This can achieve that the external heating lamps in the first external heating lamp group and the second external heating lamp group radiate different positions in the edge area of ​​the silicon wafer. The radiation range of the two external heating lamps in the first external heating lamp group is closer to the half radius of the silicon wafer, so that a higher temperature can be applied to the R / 2 area of ​​the silicon wafer, where R is the radius of the silicon wafer.

[0060] Optionally, the number of the first external heating lamp group is at least one, and the number of the second external heating lamp group is at least one.

[0061] It should also be noted that in order to ensure uniform heating of the silicon wafer, when adjusting the position of the heating lamp, the adjustment is made in units of heating lamp groups, that is, the two relative heating lamps are adjusted at the same time, so that when the rotating base and the base support frame heat the silicon wafer, the uniform heating of the silicon wafer surface is ensured, thereby improving the uniformity of the epitaxial layer growth on the silicon wafer surface.

[0062] In some embodiments, the plurality of internal heating lamp groups include at least two first internal heating lamp groups, such as two first internal heating lamp groups, three first internal heating lamp groups, or four first internal heating lamp groups;

[0063] A line connecting two inner heating lamps in the first inner heating lamp group is a first diameter of the ring;

[0064] The first diameters corresponding to two of the first inner heating lamp groups are perpendicular to each other.

[0065] For example, in the case of including two groups of first internal heating lamps, the first diameters corresponding to the two groups of first internal heating lamps are perpendicular to each other, that is, a cross shape, such as Figure 2 As shown, Figure 2 The dot-dash line in is the first diameter. In the case of 3 groups of first internal heating lamps, the first diameters corresponding to 2 groups of first internal heating lamps among the 3 groups of first internal heating lamps are perpendicular to each other, i.e., they are cross-shaped, and the positions of the two internal heating lamps in the remaining 1 group of first internal heating lamps are not limited. In the case of 4 groups of first internal heating lamps, the first diameters corresponding to 2 groups of first internal heating lamps among the 4 groups of first internal heating lamps are perpendicular to each other, i.e., they are cross-shaped, and the positions of the two internal heating lamps in the remaining 2 groups of first internal heating lamps are not limited, and their connecting lines may be perpendicular to each other or not.

[0066] By arranging two groups of first inner heating lamps whose connection lines are perpendicular to each other, uniform heating of the silicon wafer can be achieved and the heating efficiency can be improved.

[0067] In some embodiments, the plurality of groups of external heating lamps include at least two groups of first external heating lamps, such as 2 groups of first external heating lamps, 3 groups of first external heating lamps, or 4 groups of first external heating lamps;

[0068] A line connecting two external heating lamps in the first external heating lamp group is a second diameter of the ring;

[0069] The second diameters corresponding to two of the first external heating lamp groups are perpendicular to each other.

[0070] For example, in the case of including two groups of first external heating lamps, the second diameters corresponding to the two groups of first external heating lamps are perpendicular to each other, that is, a cross shape, such as Figure 2 As shown, Figure 2 The dotted line in is the second diameter. In the case of 3 groups of first external heating lamps, the second diameters corresponding to 2 groups of first external heating lamps among the 3 groups of first external heating lamps are perpendicular to each other, that is, they are cross-shaped, and the positions of the two external heating lamps in the remaining 1 group of first external heating lamps are not limited. In the case of 4 groups of first external heating lamps, the second diameters corresponding to 2 groups of first external heating lamps among the 4 groups of first internal and external heating lamps are perpendicular to each other, that is, they are cross-shaped, and the positions of the two external heating lamps in the remaining 2 groups of first external heating lamps are not limited, and their connecting lines may be perpendicular to each other or not.

[0071] In some embodiments, the distance between the inner heating lamps in the first inner heating lamp group and the center of the ring is 152 mm-158 mm. Preferably, the distance between the inner heating lamps in the first inner heating lamp group and the center of the ring is 155 mm. Figure 2 shown.

[0072] The distance between the inner heating lamps in the second inner heating lamp group and the center of the ring is 147mm-151mm. Preferably, the distance between the inner heating lamps in the second inner heating lamp group and the center of the ring is 150mm.

[0073] It should also be noted that the distance between the inner heating lamps in the first inner heating lamp group and the distance between the inner heating lamps in the second inner heating lamp group and the center of the ring can also be determined according to the size of the silicon wafer or the size of the epitaxial furnace.

[0074] The distance between the inner heating lamp in the first inner heating lamp group and the center of the ring can also be set to be greater than a first preset distance than the distance between the inner heating lamp in the second inner heating lamp group and the center of the ring. The first preset distance can be determined according to the size of the silicon wafer, for example, 5 mm.

[0075] In some embodiments, the distance between the external heating lamps in the first external heating lamp group and the center of the ring is 142 mm-147 mm. Preferably, the distance between the external heating lamps in the first external heating lamp group and the center of the ring is 145 mm. Figure 2 As shown;

[0076] The distance between the external heating lamps in the second external heating lamp group and the center of the ring is 148 mm-153 mm. Preferably, the distance between the external heating lamps in the second external heating lamp group and the center of the ring is 150 mm.

[0077] It should also be noted that the distance between the external heating lamps in the first external heating lamp group and the distance between the external heating lamps in the second external heating lamp group and the center of the ring can also be determined according to the size of the silicon wafer or the size of the epitaxial furnace.

[0078] The distance between the external heating lamp in the first external heating lamp group and the center of the ring can also be set to be smaller than a second preset distance between the external heating lamp in the second external heating lamp group and the center of the ring. The second preset distance can be determined according to the size of the silicon wafer, for example, 5 mm.

[0079] In some embodiments, an outer heating lamp is provided for every other inner heating lamp or every two adjacent inner heating lamps. Figure 2 As shown, the wafer heating assembly includes 20 inner heating lamps and 12 outer heating lamps. Figure 2 In the order shown, an outer heating lamp is arranged in a ring shape every other inner heating lamp or every two adjacent inner heating lamps.

[0080] In some embodiments, the silicon wafer heating assembly further comprises: an internal reflection plate;

[0081] The inner reflection plate is located between the inner heating lamp and the silicon wafer;

[0082] The heat radiation of the inner heating lamp is reflected by the inner reflection plate to the central area of ​​the silicon wafer in the radial direction.

[0083] It should be noted that the reason why the internal heating lamp can irradiate the central area of ​​the silicon wafer is that the internal reflection plate is set to a certain curvature to reflect the light path, thereby achieving heating of the central area of ​​the silicon wafer. The number of the internal reflection plate is at least one or at least one group, and each group of internal reflection plates includes two internal reflection plates. Among them, the curvature of the internal reflection plate corresponding to the internal heating lamp of the first internal heating lamp group is the same as the curvature of the internal reflection plate corresponding to the internal heating lamp of the second internal heating lamp group. Therefore, by setting the straight-line distance between the two internal heating lamps in the first internal heating lamp group to be greater than the straight-line distance between the two internal heating lamps in the second internal heating lamp group, the radiation range of the two internal heating lamps in the first internal heating lamp group can be closer to the half radius of the silicon wafer, so that a higher temperature can be applied to the R / 2 area of ​​the silicon wafer, thereby achieving more uniform thermal radiation to the silicon wafer, thereby improving resistivity uniformity.

[0084] In some embodiments, the silicon wafer heating assembly further includes: an outer reflection plate;

[0085] The outer reflection plate is located between the outer heating lamp and the silicon wafer;

[0086] The heat radiation of the external heating lamp is reflected by the external reflection plate to the edge area of ​​the silicon wafer in the radial direction.

[0087] It should be noted that the reason why the external heating lamp can irradiate the edge area of ​​the silicon wafer is that the external reflection plate is set to a certain curvature to reflect the light path, thereby achieving heating of the edge area of ​​the silicon wafer. The number of the external reflection plate is at least one or at least one group, and each group of external reflection plates includes two external reflection plates. Among them, the curvature of the external reflection plate corresponding to the external heating lamp of the first external heating lamp group is the same as the curvature of the external reflection plate corresponding to the external heating lamp of the second external heating lamp group. Therefore, by setting the straight-line distance between the two external heating lamps in the first external heating lamp group to be smaller than the straight-line distance between the two external heating lamps in the second external heating lamp group, the radiation range of the two external heating lamps in the first external heating lamp group can be closer to the half radius of the silicon wafer, so that a higher temperature can be applied to the R / 2 area of ​​the silicon wafer, thereby achieving more uniform thermal radiation to the silicon wafer, thereby improving the resistivity uniformity.

[0088] Optionally, the inner reflective plate and the outer reflective plate may be made of gold, silver or platinum.

[0089] In some embodiments, the silicon wafer heating assembly further comprises: a lamp holder bracket formed in a ring shape, a heating lamp holder is arranged on the lamp holder bracket, and the heating lamp holder is used to support the inner heating lamp and the outer heating lamp.

[0090] Wherein, the heating lamp is inserted into the lamp holder, and the lamp holder is a structure with adjustable position in the lamp holder bracket, so that the distance between the relative inner heating lamp and the relative outer heating lamp can be quickly adjusted.

[0091] Preferably, the inner diameter of the lamp holder bracket is 300 mm and the radius is 150 mm.

[0092] An embodiment of the present invention further provides a silicon wafer epitaxial furnace, comprising a susceptor, a susceptor support frame and two silicon wafer heating assemblies as described in any one of the above;

[0093] Wherein, the base support frame is arranged below the base, the base support frame is used to support the base, and the base is used to carry the silicon wafer;

[0094] A silicon wafer heating assembly is disposed above the silicon wafer and is used to heat the upper surface of the silicon wafer;

[0095] Another silicon wafer heating component is disposed below the silicon wafer and is used for heating the lower surface of the silicon wafer.

[0096] It should be noted that, in the silicon wafer epitaxial furnace of this embodiment, the position and quantity of the first inner heating lamp group and the position and quantity of the first outer heating lamp group in the two silicon wafer heating assemblies may be the same or different.

[0097] By providing two silicon wafer heating components, the epitaxial growth process on the surface of the silicon wafer can be completed quickly and efficiently, so that the resistivity uniformity of the epitaxial layers on both surfaces of the silicon wafer is improved.

[0098] Through experimental verification, such as Figure 1 In the resistivity schematic diagram of the epitaxial layer shown in FIG. 1 , the resistivities corresponding to 9 test points are selected, namely, the resistivity of the center point, the resistivity of 4 points on the radius, and the resistivity of 4 points at the edge. The resistivities corresponding to the 9 test points are 10.371, 10.439, 10.474, 10.688, 10.498, 10.218, 10.250, 10.355 and 10.118, respectively. The uniformity of the resistivity is 2.74%. The resistivity schematic diagram of the epitaxial layer of the silicon wafer obtained by the epitaxial growth process of the epitaxial furnace provided in the embodiment of the present invention is shown in FIG. Figure 3 As shown in the figure, the different color levels represent the different resistivity of the epitaxial layer, red represents low resistivity, and blue represents high resistivity. Figure 3It can be seen that the resistivity of the epitaxial layer has an obvious color gradation distribution and is relatively uniform, with high uniformity. Similarly, the resistivity corresponding to 9 test points at the same position are selected, and the resistivity corresponding to the 9 test points are: 10.348, 10.278, 10.247, 10.345, 10.254, 10.648, 10.595, 10.688, 10.599, and the uniformity of the resistivity is 2.11%. It can be seen that the resistivity uniformity has also been improved to a certain extent.

[0099] It should be noted that the silicon wafer epitaxial furnace provided in the embodiment of the present invention includes the silicon wafer heating assembly as described in any one of the above, and all embodiments of the above-mentioned silicon wafer heating assembly are applicable to the silicon wafer epitaxial furnace and can achieve the same or similar technical effects.

[0100] There are a few points to note:

[0101] The drawings of the embodiments of the present invention only involve structures related to the embodiments of the present disclosure, and other structures may refer to general designs.

[0102] For the sake of clarity, in the drawings used to describe the embodiments of the present disclosure, the thickness of the layer or region is enlarged or reduced, that is, these drawings are not drawn according to the actual scale. It is understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" another element or there may be an intermediate element.

[0103] In the absence of conflict, the embodiments of the present disclosure and the features therein may be combined with each other to obtain new embodiments.

[0104] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A silicon wafer heating assembly, characterized in that: The silicon wafer heating assembly is used to heat the silicon wafer in the silicon wafer epitaxial growth furnace; The silicon wafer heating assembly comprises: A plurality of internal heating lamp groups, each internal heating lamp group comprising two internal heating lamps arranged opposite to each other, the internal heating lamps being used to heat the central area of ​​the silicon wafer in the radial direction; A plurality of external heating lamp groups, each of which includes two external heating lamps arranged opposite to each other, and the external heating lamps are used to heat the edge area of ​​the silicon wafer in the radial direction; The inner heating lamps and the outer heating lamps are arranged in a preset order to form a circumferentially arranged ring, the line connecting the two inner heating lamps in each group of the inner heating lamps is the diameter of the ring, and the line connecting the two outer heating lamps in each group of the outer heating lamps is the diameter of the ring; Wherein, the plurality of internal heating lamp groups include a first internal heating lamp group and a second internal heating lamp group, and a straight-line distance between two internal heating lamps in the first internal heating lamp group is greater than a straight-line distance between two internal heating lamps in the second internal heating lamp group; The plurality of external heating lamp groups include a first external heating lamp group and a second external heating lamp group, wherein a straight-line distance between two external heating lamps in the first external heating lamp group is smaller than a straight-line distance between two external heating lamps in the second external heating lamp group.

2. The silicon wafer heating assembly according to claim 1, characterized in that: The multiple groups of internal heating lamp groups include at least two groups of first internal heating lamp groups; A line connecting two inner heating lamps in the first inner heating lamp group is a first diameter of the ring; The first diameters corresponding to two of the first inner heating lamp groups are perpendicular to each other.

3. The silicon wafer heating assembly according to claim 1, characterized in that: The plurality of external heating lamp groups include at least two first external heating lamp groups; A line connecting two external heating lamps in the first external heating lamp group is a second diameter of the ring; The second diameters corresponding to two of the first external heating lamp groups are perpendicular to each other.

4. The silicon wafer heating assembly according to claim 1, characterized in that: The distance between the inner heating lamp in the first inner heating lamp group and the center of the ring is 152 mm-158 mm; The distance between the inner heating lamps in the second inner heating lamp group and the center of the ring is 147mm-151mm.

5. The silicon wafer heating assembly according to claim 1, characterized in that: The distance between the external heating lamp in the first external heating lamp group and the center of the ring is 142 mm-147 mm; The distance between the external heating lamps in the second external heating lamp group and the center of the ring is 148 mm-153 mm.

6. The silicon wafer heating assembly according to claim 1, characterized in that: An outer heating lamp is provided for every other inner heating lamp or every two adjacent inner heating lamps.

7. The silicon wafer heating assembly according to claim 1, characterized in that: The silicon wafer heating assembly further includes: an internal reflection plate; The inner reflection plate is located between the inner heating lamp and the silicon wafer; The heat radiation of the inner heating lamp is reflected by the inner reflection plate to the central area of ​​the silicon wafer in the radial direction.

8. The silicon wafer heating assembly according to claim 1, characterized in that: The silicon wafer heating assembly further includes: an outer reflection plate; The outer reflection plate is located between the outer heating lamp and the silicon wafer; The heat radiation of the external heating lamp is reflected by the external reflection plate to the edge area of ​​the silicon wafer in the radial direction.

9. The silicon wafer heating assembly according to claim 1, characterized in that: The silicon wafer heating assembly further comprises: a lamp holder bracket formed in a ring shape, a heating lamp holder is arranged on the lamp holder bracket, and the heating lamp holder is used to carry the inner heating lamp and the outer heating lamp.

10. A silicon wafer epitaxial furnace, characterized in that: It comprises a base, a base support frame and two silicon wafer heating assemblies as claimed in any one of claims 1 to 9; Wherein, the base support frame is arranged below the base, the base support frame is used to support the base, and the base is used to carry the silicon wafer; A silicon wafer heating assembly is disposed above the silicon wafer and is used to heat the upper surface of the silicon wafer; Another silicon wafer heating component is disposed below the silicon wafer and is used for heating the lower surface of the silicon wafer.

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