CN218893765U - Tray for growing semiconductor epitaxial wafer - Google Patents

Abstract

The utility model discloses a tray for growing a semiconductor epitaxial wafer, which comprises a tray main body, a positioning ring and a heat-resistant structure, wherein the tray main body is provided with a plurality of positioning holes; the upper surface of the tray main body is provided with a boss; the shape of the inner wall of the positioning ring corresponds to the shape of the side wall of the tray main body, and the positioning ring is clamped outside the tray main body; the heat-resistant structure is arranged on the boss, and the center of the heat-resistant structure coincides with the center of the boss. The heat-resistant structure can prevent heat from being conducted from the tray main body to the wafer in use, so that the temperature consistency of the center and the edge of the wafer is improved, the shape consistency, concentration and thickness uniformity of the center and the edge of the epitaxial wafer are improved, the stable reliability of production is improved, the yield of epitaxy and devices is increased, and the cost is reduced.

Description

Tray for growing semiconductor epitaxial wafer

Technical Field

The utility model relates to the technical field of semiconductor epitaxy, in particular to a tray for growing high-quality semiconductor epitaxial wafers.

Background

The third-generation semiconductor silicon carbide material has been paid more attention to the fields of new energy automobiles, photovoltaic power generation, rail transit, smart power grids and the like in recent years, and has the characteristics of high saturated electron mobility, high heat conductivity and strong radiation resistance. The corresponding device manufactured by the third-generation semiconductor silicon carbide material has the advantages of quick response, low energy consumption, good heat dissipation, small volume and the like, and has great potential.

Currently, silicon carbide wafer epitaxy generally adopts a horizontal hot wall MOCVD apparatus, and the tray structure is shown in FIGS. 1a-1b, and the tray is composed of a tray main body 110 'and a positioning ring 120', wherein a boss 111 'is arranged in the middle of the tray main body 110', and the positioning ring 120 'is provided with a limiting edge 121'. In use, the positioning ring 120 ' is clamped outside the boss 111 ' of the tray main body 110 ', so that the inner wall of the positioning ring 120 ' abuts against the side wall of the tray main body 110 ', as shown in fig. 1 b.

In the epitaxial growth process, the wafer is placed on the boss 111 ' of the tray main body 110 ' and is positioned in the positioning ring 120 ', and the positioning edge of the wafer is parallel to the limiting edge 121 ' of the positioning ring 120 ' so as to achieve the positioning effect. Eddy currents are generated in the graphite fitting by the high frequency ac coil, thereby forming a temperature field around the wafer. However, because the heat conduction and heat dissipation conditions of the center and the edge of the wafer are different, the center temperature of the wafer is higher than that of the edge, and the uniformity of the surface morphology, the concentration and the thickness of the center and the edge of the wafer are affected, so that the yield of epitaxy and devices is reduced, and the cost is increased.

Therefore, it is necessary to provide a tray that improves the temperature uniformity between the center and the edge of the wafer, thereby improving the topography uniformity, concentration and thickness uniformity of the center and the edge of the epitaxial wafer, to solve the above-mentioned problems.

Disclosure of Invention

The utility model aims to provide a tray for growing a semiconductor epitaxial wafer, which improves the temperature consistency between the center and the edge of the wafer, thereby improving the morphology consistency, concentration and thickness uniformity of the center and the edge of the epitaxial wafer.

In order to achieve the above purpose, the technical scheme of the utility model is as follows: the tray for growing the semiconductor epitaxial wafer comprises a tray main body, a positioning ring and a heat-resistant structure; the upper surface of the tray main body is provided with a boss; the shape of the inner wall of the positioning ring corresponds to the shape of the side wall of the tray main body, and the positioning ring is clamped outside the tray main body; the heat-resistant structure is arranged on the boss, and the center of the heat-resistant structure coincides with the center of the boss.

Preferably, the heat-resistant structure comprises a concave part concavely arranged on the boss.

Preferably, the concave part is cone-shaped, and the circle center of the concave part coincides with the circle center of the boss.

Preferably, the heat-resistant structure further comprises a cone embedded in the concave part, and the upper surface of the cone and the upper surface of the boss are located on the same plane.

Preferably, the heat-resistant structure comprises a double cone embedded in the boss, and the circle center of the double cone coincides with the circle center of the boss.

Preferably, the heat-resistant structure comprises a cylinder and a plurality of circular cylinders, the circular cylinders and the cylinder are sequentially arranged on the boss at intervals from outside to inside, and the circular cylinders and the cylinder are concentrically arranged.

Preferably, the widths of the circular cylinders and the diameters of the cylinders are sequentially increased from outside to inside.

Preferably, the widths of the circular cylinders and the diameters of the cylinders are the same.

Preferably, the distance between two adjacent circular cylinders and the distance between the circular cylinders and the cylinder are sequentially reduced or the same from outside to inside.

Preferably, the edge of the boss is provided with a protruding portion, the protruding portion and the surface of the boss are in a step shape, and the protruding portion is used for supporting the edge of the wafer.

Compared with the prior art, the tray for growing the semiconductor epitaxial wafer comprises a tray main body, a positioning ring and a heat-resistant structure; the upper surface of the tray main body is provided with a boss; the shape of the inner wall of the positioning ring corresponds to the shape of the side wall of the tray main body, and the positioning ring is clamped outside the tray main body and is abutted against the side wall of the tray main body; the heat-resistant structure is arranged on the boss, and the center of the heat-resistant structure is overlapped with the center of the boss of the tray main body. The heat-resistant structure can prevent heat from being conducted from the tray main body to the wafer in use, so that the temperature consistency of the center and the edge of the wafer is improved, the shape consistency, the concentration and the thickness uniformity of the center and the edge of the epitaxial wafer are improved, the stable reliability of production is improved, the yield of epitaxy and devices is increased, and the cost is reduced.

Drawings

Fig. 1a is a top view of a prior art pallet.

Fig. 1b is a cross-sectional view of fig. 1 a.

Fig. 2a is a top view of a tray in a first embodiment of the utility model.

Fig. 2b is a cross-sectional view of fig. 2 a.

Fig. 3a is a top view of a tray in a second embodiment of the utility model.

Fig. 3b is a cross-sectional view of fig. 3 a.

Fig. 4a is a top view of a tray in a third embodiment of the utility model.

Fig. 4b is a cross-sectional view of fig. 4 a.

Fig. 5a is a top view of a tray in a fourth embodiment of the utility model.

Fig. 5b is a cross-sectional view of fig. 5 a.

Fig. 6a is a top view of a tray in a fifth embodiment of the utility model.

Fig. 6b is a cross-sectional view of fig. 6 a.

Fig. 7a is a top view of a tray in a sixth embodiment of the utility model.

Fig. 7b is a cross-sectional view of fig. 7 a.

Fig. 8a is a top view of a tray in a seventh embodiment of the utility model.

Fig. 8b is a cross-sectional view of fig. 8 a.

Detailed Description

Embodiments of the present utility model will now be described with reference to the drawings, wherein like reference numerals represent like elements throughout. It should be noted that, the description of the azimuth or the positional relationship indicated by the present utility model, such as up, down, left, right, front, back, etc., is based on the azimuth or the positional relationship shown in the drawings, and is only for convenience in describing the technical solution of the present application and/or simplifying the description, and does not indicate or imply that the device or element to be referred to must have a specific azimuth, be configured and operated in a specific azimuth, and therefore should not be construed as limiting the present application. First, second, etc. are described solely for distinguishing between technical features and should not be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of technical features indicated.

Referring to fig. 2 a-8 b, a tray 100 for growing semiconductor epitaxial wafers according to the present utility model includes a tray main body 110, a positioning ring 120, and a heat-resistant structure 130. The upper surface of the tray main body 110 is provided with a boss 111; the shape of the inner wall of the positioning ring 120 corresponds to the shape of the side wall of the tray main body 110, and the positioning ring 120 is engaged with the outside of the boss 111 and abuts against the side wall of the tray main body 110; the heat-resistant structure 130 is disposed on the boss 111, and the center of the heat-resistant structure 130 coincides with the center of the boss 111, where the heat-resistant structure 130 has the function of preventing heat from being conducted from the tray 100 to the wafer, so that the temperature consistency of the center and the edge of the wafer can be improved, and the morphology consistency, thickness uniformity and thickness consistency of the center and the edge of the epitaxial wafer are improved.

Different embodiments of the tray 100 for growing semiconductor epitaxial wafers according to the present utility model will be described with reference to fig. 2 a-8 b, respectively.

Referring to fig. 2 a-2 b, in the first embodiment of the present utility model, a boss 111 is disposed on the upper surface of the tray main body 110, so that the tray main body 110 has a first side wall 112 and a second side wall 113 with a stepped shape, and the outer diameter of the first side wall 112 is smaller than that of the second side wall 113, as shown in fig. 2 b. The positioning ring 120 is provided with a step hole in a penetrating manner, so that the shape of the inner wall of the positioning ring 120 corresponds to the shape of the side wall of the tray main body 110, and the positioning ring 120 is clamped outside the tray main body 110, that is, the positioning ring 120 is carried on the tray main body 110, and the inner wall of the positioning ring is abutted against the first side wall 112 and the second side wall 113 of the tray main body 110, as shown in fig. 2 b.

Referring to fig. 2a, in the present embodiment, the projection of the inner wall of the positioning ring 120 on the upper surface of the tray main body 110 has a linear limit edge 121. In use, the positioning ring 120 is clamped outside the boss 111 of the tray main body 110, and the limiting edge 121 is used to cooperate with the wafer to position the wafer.

With continued reference to fig. 2 a-2 b, in this embodiment, the heat-blocking structure 130 is a concave portion concavely disposed on the boss 111, and the concave portion is conical, and a center of the concave portion coincides with a center of the boss 111. And, the tray main body 110 and the positioning ring 120 are made of graphite, and the concave part is not filled with any material. When the tray 100 is used, the wafer is placed on the boss 111 of the tray main body 110 and is positioned in the positioning ring 120, the positioning edge of the wafer is parallel to the limiting edge 121 of the positioning ring 120 to achieve the positioning effect, and the arrangement of the concave part has the effect of preventing heat from being conducted from the tray main body 110 to the wafer, so that the temperature consistency of the center and the edge of the wafer is improved.

In the second example of the present utility model, the structures of the tray main body 110 and the positioning ring 120 are the same as those of the first example described above, and thus the description thereof will not be repeated, and only the heat blocking structure 130 thereof will be described.

In this embodiment, the heat-resistant structure 130 is a cone 131 that is embedded in the boss 111. More specifically, the boss 111 of the tray main body 110 is concavely provided with a recess corresponding to the shape of the cone 131, the cone 131 is embedded in the recess, the upper surface of the cone 131 and the upper surface of the boss 111 are located on the same plane, and the center of the cone 131 coincides with the center of the boss 111, as shown in fig. 3 b. In this embodiment, the material of the tray main body 110 and the positioning ring 120 is graphite, and the material of the cone 131 of the heat-resisting structure 130 is silicon carbide, tantalum carbide, boron nitride, silicon nitride, boron carbide, titanium boride, or the like.

When the tray 100 is used, the wafer is placed on the boss 111 of the tray main body 110 and is located inside the positioning ring 120, and the positioning edge of the wafer is parallel to the limiting edge 121 of the positioning ring 120 to achieve the positioning effect. While the cone 131 has a function of blocking heat conduction from the tray main body 110 to the wafer, thereby improving temperature uniformity of the center and edge of the wafer.

In the third embodiment of the present utility model, the positioning ring 120 and the heat-blocking structure 130 are configured and arranged in the same manner as in the second embodiment, and thus the description thereof will not be repeated, and only the differences between the tray main body 110 and the second embodiment will be described.

In this embodiment, a protruding portion 114 is further disposed at an edge position of the boss 111, and the protruding portion 114 is stepped with a surface of the boss 111, as shown in fig. 4 b. When the tray 100 is used, the wafer is placed on the boss 111 of the tray main body 110 and is positioned inside the positioning ring 120, the edge of the wafer is supported on the boss 114, and the positioning edge of the wafer is parallel to the limiting edge 121 of the positioning ring 120 to achieve the positioning effect.

In the fourth example of the present utility model, which is shown in fig. 5 a-5 b, the difference from the second example is only that the heat-resistant structure 130 is different, and the structures of other parts are the same, and the description is not repeated, and only the heat-resistant structure 130 is described below.

In this embodiment, the heat-resistant structure 130 includes a double cone 132 embedded in the boss 111, and the center of the double cone 132 coincides with the center of the boss 111. More specifically, the double cone 132 is formed by combining two cones, the bottom surfaces of the two cones are attached, the vertexes of the two cones are located in opposite directions, and the centers of the vertexes of the two cones and the center of the bottom surface coincide with the center of the boss 111.

Referring to fig. 5 a-5 b again, in this embodiment, the materials of the tray main body 110 and the positioning ring 120 are graphite, and the material of the double cone 132 of the thermal insulation structure 130 is silicon carbide, tantalum carbide, boron nitride, silicon nitride, boron carbide or titanium boride. When the tray 100 is used, the wafer is placed on the boss 111 of the tray main body 110 and is positioned inside the positioning ring 120, and the positioning edge of the wafer is parallel to the limiting edge 121 of the positioning ring 120 so as to achieve the positioning effect. While the double cone 132 has the effect of blocking heat transfer from the tray body 110 to the wafer, thereby improving the temperature uniformity of the center and edge of the wafer.

In the fifth embodiment of the present utility model, which is shown in fig. 6 a-6 b, the difference from the second embodiment is only that the heat-resistant structure 130 is different, and the structures of other parts are the same, and the description is not repeated, and only the heat-resistant structure 130 is described below.

In this embodiment, the heat-resistant structure 130 includes a cylinder 134 and a plurality of circular cylinders 133, the circular cylinders 133 and the cylinder 134 are sequentially disposed on the boss 111 from outside to inside at intervals, and the circular cylinders 133 and the cylinder 134 are concentrically disposed. Moreover, the widths of the circular cylinders 133 and the diameters of the cylinders 134 are sequentially increased from outside to inside, and the intervals between two adjacent circular cylinders 133 and the intervals between the circular cylinders 133 and the cylinders 134 are sequentially decreased from outside to inside or are the same.

With continued reference to fig. 6 a-6 b, in this embodiment, the heat-resistant structure 130 specifically includes a cylinder 134 and three circular cylinders 133, the three circular cylinders 133 are a first circular cylinder 1331, a second circular cylinder 1332, and a third circular cylinder 1333 from outside to inside, the cylinder 134 is disposed in the middle of the third circular cylinder 1333, and the first circular cylinder 1331, the second circular cylinder 1332, the third circular cylinder 1333, and the cylinder 134 are all concentrically disposed, and the four are also disposed with the boss 111 of the tray main body 110 as a center of a circle.

With continued reference to fig. 6 a-6 b, in the present embodiment, the widths of the first circular cylinder 1331, the second circular cylinder 1332 and the third circular cylinder 1333 are L1, L2 and L3 in sequence, the diameter of the cylinder 134 is L4, the spacing between the first circular cylinder 1331, the second circular cylinder 1332 and the third circular cylinder 1333 is D1 and D2 in sequence, and the spacing between the third circular cylinder 1333 and the cylinder 134 is D3. And satisfies the following relationship: l1 is more than L2 and less than L3 and less than L4, and D1 is more than or equal to D2 and more than or equal to D3.

In the present embodiment, the tray main body 110 and the positioning ring 120 are made of graphite, and the first circular cylinder 1331, the second circular cylinder 1332, the third circular cylinder 1333 and the cylinder 134 of the heat-resistant structure 130 are made of silicon carbide, tantalum carbide, boron nitride, silicon nitride, boron carbide or titanium boride. When the tray 100 is used, the wafer is placed on the boss 111 of the tray main body 110 and is positioned inside the positioning ring 120, and the positioning edge of the wafer is parallel to the limiting edge 121 of the positioning ring 120 so as to achieve the positioning effect. And the heat blocking structure 130 has a function of blocking heat conduction from the tray body 110 to the wafer, thereby improving temperature uniformity of the center and edge of the wafer.

In the sixth example of the present utility model, which is shown below with reference to fig. 7a to 7b, the difference from the fifth example is that the structure of the tray main body 110 is slightly different, and the other structures are the same, and the description thereof will not be repeated, and only the tray main body 110 will be described below.

In this embodiment, a protruding portion 114 is further disposed at an edge position of the boss 111, the protruding portion 114 is stepped with a surface of the boss 111, and the protruding portion 114 is used for supporting an edge of the wafer. Specifically, when the tray 100 is used, the wafer is placed on the boss 111 of the tray main body 110 and is located inside the positioning ring 120, and the edge of the wafer is supported on the boss 114, and the positioning edge of the wafer is parallel to the limiting edge 121 of the positioning ring 120 to achieve the positioning effect.

In the seventh embodiment of the present utility model, as shown in fig. 8 a-8 b, the difference from the fifth embodiment is only that the heat-resistant structure 130 is different, and the structures of other parts are the same, and the description is not repeated, and only the heat-resistant structure 130 is described below.

In this embodiment, the heat-resistant structure 130 includes a cylinder 134 and a plurality of circular cylinders 133, the circular cylinders 133 and the cylinder 134 are sequentially disposed on the boss 111 from outside to inside at intervals, and the circular cylinders 133 and the cylinder 134 are concentrically disposed. Moreover, the widths of the circular cylinders 133 and the diameters of the cylinders 134 are the same, and the spacing between two adjacent circular cylinders 133 and the spacing between the circular cylinders 133 and the cylinders 134 are sequentially reduced from outside to inside or are the same.

Referring to fig. 8 a-8 b, in this embodiment, the heat-resistant structure 130 specifically includes a cylinder 134 and five circular cylinders 133, the five circular cylinders 133 are respectively a first circular cylinder 1331, a second circular cylinder 1332, a third circular cylinder 1333, a fourth circular cylinder 1334, and a fifth circular cylinder 1335 from outside to inside, the cylinder 134 is disposed in the middle of the fifth circular cylinder 1335, and the first circular cylinder 1331, the second circular cylinder 1332, the third circular cylinder 1333, the fourth circular cylinder 1334, the fifth circular cylinder 1335, and the cylinder 134 are concentrically disposed, and the sixth is disposed with the boss 111 of the tray main body 110 as a center of a circle.

With continued reference to fig. 8 a-8 b, in the present embodiment, the widths of the first circular cylinder 1331, the second circular cylinder 1332, the third circular cylinder 1333, the fourth circular cylinder 1334, and the fifth circular cylinder 1335 are sequentially L1, L2, L3, L4, and L5, the diameter of the cylinder 134 is L6, and the intervals between the first circular cylinder 1331, the second circular cylinder 1332, the third circular cylinder 1333, the fourth circular cylinder 1334, and the fifth circular cylinder 1335 are D1, D2, D3, and D4 from outside to inside, respectively, and the interval between the fifth circular cylinder 1335 and the cylinder 134 is D5. The relationship in this embodiment is: l1=l2=l3=l4=l5=l6, and D1 > D2 > D3 > D4 > D5.

In this embodiment, the materials of the tray main body 110 and the positioning ring 120 are graphite, and the material of the heat-resistant structure 130 is silicon carbide, tantalum carbide, boron nitride, silicon nitride, boron carbide, titanium boride, or the like. When the tray 100 is used, the wafer is placed on the boss 111 of the tray main body 110 and is positioned inside the positioning ring 120, and the positioning edge of the wafer is parallel to the limiting edge 121 of the positioning ring 120 so as to achieve the positioning effect. The heat blocking structure 130 has a function of blocking heat conduction from the tray body 110 to the wafer, thereby improving temperature uniformity of the center and edge of the wafer.

In summary, since the tray 100 for growing semiconductor epitaxial wafers of the present utility model includes the tray main body 110, the positioning ring 120, and the heat-resistant structure 130; the upper surface of the tray main body 110 is provided with a boss 111; the shape of the inner wall of the positioning ring 120 corresponds to the shape of the side wall of the tray main body 110, and the positioning ring 120 is clamped outside the tray main body 110 and is abutted against the side wall of the tray main body 110; the heat-resistant structure 130 is disposed on the boss 111, and the center of the heat-resistant structure 130 coincides with the center of the boss 111. The heat blocking structure 130 can prevent heat from being conducted from the tray main body 110 to the wafer during use, so that the temperature consistency of the center and the edge of the wafer is improved, the shape consistency, concentration and thickness uniformity of the center and the edge of the epitaxial wafer are improved, the stable reliability of production is improved, the yield of epitaxy and devices is increased, and the cost is reduced.

The structure, shape, etc. of the epitaxial wafer according to the present utility model are conventional structures well known to those skilled in the art, and will not be described in detail herein.

The foregoing description of the preferred embodiments of the present utility model is not intended to limit the scope of the claims, which follow, as defined in the claims.

Claims (10)

1. A tray for growing semiconductor epitaxial wafers, comprising:

the tray main body is provided with a boss on the upper surface;

the shape of the inner wall of the positioning ring corresponds to the shape of the side wall of the tray main body, and the positioning ring is clamped outside the tray main body;

and the heat-resistant structure is arranged on the boss, and the center of the heat-resistant structure coincides with the center of the boss.

2. The tray for growing semiconductor epitaxial wafers of claim 1 wherein the heat-resistant structure comprises a recess recessed into the boss.

3. The tray for growing semiconductor epitaxial wafers of claim 2 wherein the recess is conical and the center of the recess coincides with the center of the boss.

4. The tray for growing semiconductor epitaxial wafers of claim 2 wherein the heat-resistant structure further comprises a cone fitted in the recess, the upper surface of the cone being in the same plane as the upper surface of the boss.

5. The tray for growing semiconductor epitaxial wafers of claim 1 wherein the heat-resistant structure comprises a double cone fitted inside the boss, the center of the double cone coinciding with the center of the boss.

6. The tray for growing semiconductor epitaxial wafers of claim 1, wherein the heat-resistant structure comprises a cylinder and a plurality of circular cylinders, the circular cylinders and the cylinder are sequentially arranged on the boss at intervals from outside to inside, and the circular cylinders and the cylinder are concentrically arranged.

7. The tray for growing semiconductor epitaxial wafers of claim 6 wherein the widths of the plurality of circular cylinders and the diameters of the cylinders increase sequentially from outside to inside.

8. The tray for growing semiconductor epitaxial wafers of claim 6 wherein the widths of the plurality of circular cylinders and the diameters of the cylinders are the same.

9. The tray for growing semiconductor epitaxial wafers according to claim 7 or 8, wherein the spacing between adjacent two of the circular cylinders and the spacing between the circular cylinders and the cylinder are sequentially reduced or the same from outside to inside.

10. The tray for growing semiconductor epitaxial wafers according to any one of claims 1 to 8, wherein the boss is provided at an edge position with a boss, the boss being stepped with a surface of the boss, the boss being for supporting an edge of a wafer.

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