Wafer tray and wafer drying device

Abstract

The invention discloses a wafer tray and a wafer drying device.The wafer tray comprises a base, a first extension arm and a tray body, a first through hole is formed in the base, and the base is used for bearing a wafer to be dried; the first extension arm extends into the first through hole from the surface of the inner wall of the first through hole; the disc body is arranged in the first through hole and connected with the first extension arm, the disc body is located below the to-be-dried wafer, the disc body, the first extension arm and the inner wall of the first through hole define a flow channel structure, and supercritical fluid flows through the flow channel structure. The supercritical fluid is blown to the surface of the wafer through the flow channel structure and does not need to pass through the disc body, so that the influence of the supercritical fluid on the surface temperature of the to-be-dried wafer above the disc body is reduced, the surface temperature of the to-be-dried wafer above the disc body is uniformly distributed, the situation that an isopropanol liquid film on the surface of the wafer is not uniformly distributed is reduced, and the quality of the to-be-dried wafer is improved. And the yield of the wafer is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of wafer drying, and in particular to a wafer tray and a wafer drying device. Background Art

[0002] In the semiconductor manufacturing process, in order to ensure the cleanliness of the wafer, a wet cleaning process is often required to clean the wafer to remove impurities and residues on the wafer surface. After the cleaning process is completed, the wafer needs to be dried.

[0003] At present, supercritical fluid is often used to dry wafers. The tray carrying the wafers is placed in the process chamber, and the pressure and temperature in the process chamber are adjusted to meet the working environment of the supercritical fluid. The tray is provided with several through holes, and the supercritical fluid is blown to the surface of the wafer through these through holes to remove moisture from the surface of the wafer. However, the through holes on the tray will cause uneven temperature distribution on the surface of the wafer, which will cause uneven distribution of the isopropyl alcohol liquid film on the surface of the wafer, and then cause defects on the surface of the wafer. Summary of the invention

[0004] In view of this, the present invention provides a wafer tray and a wafer drying device to solve the problem that the through holes on the existing tray will cause uneven temperature distribution on the surface of the wafer thereon, thereby causing uneven distribution of the isopropyl alcohol liquid film on the surface of the wafer, and further causing defects on the surface of the wafer.

[0005] The present invention provides a wafer tray, comprising:

[0006] A base body is provided with a first through hole, and the base body is used to carry the wafer to be dried;

[0007] A first extension arm extends from the inner wall surface of the first through hole into the first through hole;

[0008] A disk body, disposed in the first through hole and connected to the first extension arm, the disk body being located below the wafer;

[0009] The disc body and the inner wall of the first through hole are combined to form a flow channel structure, and the flow channel structure is used for supercritical fluid to flow through.

[0010] Optionally, in the above-mentioned wafer tray, a first groove is formed on the inner wall of the first through hole, one end of the first extension arm is plugged into the first groove, and the other end extends out of the first groove and is fixedly connected to the tray body.

[0011] Optionally, in the above-mentioned wafer tray, a plurality of first extension arms are provided, and the plurality of first extension arms are spaced apart and distributed around the outer circumference of the tray body.

[0012] Optionally, the above wafer tray further includes:

[0013] A support leg, wherein a second groove is formed on the base, the first through hole is formed at the bottom of the second groove, the support leg is fixedly connected to the bottom of the second groove, and the support leg abuts against the wafer to be dried;

[0014] The orthographic projection of the wafer to be dried on the base covers the tray.

[0015] Optionally, in the above-mentioned wafer tray, the depth of the second groove is greater than the sum of the height of the support foot and the thickness of the wafer to be dried.

[0016] Optionally, in the above-mentioned wafer tray, the tray body and the wafer to be dried are spaced apart.

[0017] Optionally, the above wafer tray further includes:

[0018] A second extension arm extends from the inner wall surface of the first through hole into the first through hole;

[0019] The supporting feet are provided in plurality, at least one of the supporting feet is fixedly connected to the second extension arm, and the plurality of supporting feet are distributed at intervals around the central axis of the disk body.

[0020] Optionally, in the above-mentioned wafer tray, the seat body comprises:

[0021] A side plate fixedly connected to the second extension arm;

[0022] The transverse plate is fixedly connected to the side plates and is perpendicular to the side plates. The transverse plate is provided with the second groove.

[0023] Optionally, the wafer tray described above has a grabbing through hole provided on the tray body.

[0024] The present invention also provides a wafer drying device, comprising the above-mentioned wafer tray.

[0025] The technical solution provided by the present invention has the following advantages:

[0026] 1. The wafer tray provided by the present invention comprises a seat, a first extension arm and a plate body, wherein the seat body is provided with a first through hole, and the seat body is used to carry the wafer to be dried; the first extension arm extends from the inner wall surface of the first through hole into the first through hole; the plate body is provided in the first through hole and connected to the first extension arm, and the plate body is located below the wafer to be dried, and the plate body, the first extension arm and the inner wall of the first through hole enclose a flow channel structure, and the flow channel structure is used to flow through a supercritical fluid. The supercritical fluid is blown toward the surface of the wafer by the flow channel structure without passing through the plate body, thereby reducing the influence of the supercritical fluid on the surface temperature of the wafer to be dried above the plate body, so that the surface temperature of the wafer to be dried above the plate body is evenly distributed, so as to reduce the uneven distribution of the isopropyl alcohol liquid film on the surface of the wafer, thereby improving the yield rate of the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a schematic diagram of the structure of the wafer tray provided by the present invention carrying the wafer;

[0029] Figure 2 It is a structural schematic diagram of a wafer tray provided by the present invention;

[0030] Figure 3 It is a structural schematic diagram of a tray body and a first extension arm in a wafer tray provided by the present invention;

[0031] Figure 4 It is a schematic diagram of temperature distribution of a wafer to be dried after using a wafer tray obtained by simulation analysis provided by the present invention;

[0032] Figure 5 The present invention provides a distribution diagram of the liquid film on the surface of the wafer to be dried after using the wafer tray, obtained by simulation analysis.

[0033] Description of reference numerals:

[0034] 100, seat body; 101, side plate; 102, cross plate;

[0035] 201, first extension arm; 202, disk body; 2021, grabbing through hole;

[0036] 300, flow channel structure;

[0037] 400, legs;

[0038] 500, second extension arm;

[0039] 600. Wafers to be dried. DETAILED DESCRIPTION

[0040] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0042] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] Example 1

[0045] The wafer tray provided in this embodiment is as follows: Figures 1 to 3 As shown, it includes a base body 100, a first extension arm 201 and a disk body 202. The base body 100 is used to carry the wafer 600 to be dried, and a first through hole is provided on the base body 100; the first extension arm 201 extends from the inner wall surface of the first through hole into the first through hole; the disk body 202 is arranged in the first through hole and connected to the first extension arm 201. The disk body 202 is located below the wafer 600 to be dried. The disk body 202, the first extension arm 201 and the inner wall of the first through hole enclose a flow channel structure 300, and the flow channel structure 300 is used to flow through a supercritical fluid.

[0046] Specifically, the base 100 is mainly used to provide support for the entire structure and provide installation space for other components. A supporting structure can be set on the base 100 to carry the wafer 600 to be dried. The base 100 can be made of a heat-conductive material, such as stainless steel, copper, aluminum or other alloys; of course, it can also be a non-heat-conductive material, such as rubber or glass. This embodiment preferably uses 316L stainless steel. On the one hand, 316L stainless steel has good corrosion resistance and high temperature resistance, which not only meets the temperature conditions of the process chamber, but also increases the service life of the wafer tray, thereby reducing the maintenance cost of the wafer tray. On the other hand, 316L stainless steel has good processing performance and is easy to cut and weld, which reduces the difficulty of processing. The specific shape of the base 100 is not limited, and it can be a disc, a rectangular parallelepiped, or other shapes that are compatible with the process chamber, such as Figure 2 As shown in the figure, the seat body 100 of this embodiment adopts a semicircular rectangular shape, and a first through hole is opened on the seat body 100. The first through hole is used to provide an installation space for the disk body 202 and to form a flow channel structure 300. The shape of the first through hole is not limited, and can be a circle, a square or other common shapes, such as Figure 2 As shown, the first through hole of this embodiment adopts a semicircle connected to a rectangle. The disk body 202 is located on the lower surface of the wafer 600 to be dried, which can prevent the supercritical fluid from blowing directly to the surface of the wafer 600 to be dried, thereby avoiding the supercritical fluid from damaging the pattern on the wafer surface. The disk body 202 is located in the first through hole, and the cross-sectional area of ​​the disk body 202 is smaller than the cross-sectional area of ​​the first through hole, so as to form a channel between the disk body 202 and the inner wall of the first through hole. The channel can guide or change the direction of the airflow to prevent the supercritical fluid from blowing directly on the wafer surface. The first extension arm 201 can be fixedly connected to the inner wall of the first through hole. The specific fixing means can be bolts or buckles or integral injection molding. The shape of the first extension arm 201 is not limited, and can be a cylinder, a cuboid, or other common shapes, such as Figure 3 As shown, the first extension arm 201 of this embodiment is a rounded rectangle. The first extension arm 201 is used to provide support for the disc body 202 and provide an installation position. Therefore, the first extension arm 201 extends from the inner wall of the first through hole to the inside of the first through hole. The inside of the first through hole refers to extending in the axial direction of the through hole. The end of the first extension arm 201 away from the inner wall of the first through hole is connected to the disc body 202. The disc body 202 can be placed on the first extension arm 201, or the disc body 202 can be connected to the first extension arm 201 by bolts, welding, bonding, or clamping. The flow channel structure 300 provides a channel for the supercritical fluid to pass through. The flow channel structure 300 is formed by the inner wall of the first through hole, the disc body 202, and the first extension arm 201. The flow channel structure 300 is used to guide or change the direction of the supercritical fluid to form a supercritical fluid with a desired flow direction.

[0047] This embodiment provides a wafer tray, such as Figure 4As shown in the figure, the temperature distribution diagram of the wafer surface after using the wafer tray obtained by simulation analysis is shown in Figure 4 In the figure, "Temperature" indicates different colors corresponding to different temperature ranges. It can be seen that most of the wafer area is the same color, and the color difference is only in the edge area of ​​the wafer. The edge area of ​​the wafer is the wafer edge removal area and does not affect the quality of the wafer. Figure 5 As shown in the figure, the distribution of the liquid film on the wafer surface after using the wafer tray obtained by simulation analysis is shown in Figure 5 In the figure, "Phase 3" indicates different colors corresponding to different thickness ranges. It can be seen that most of the area of ​​the wafer is of the same color. Obviously, the uniformity of the liquid film distribution is relatively close, while the larger color difference appears in the edge area of ​​the wafer. The supercritical fluid is blown to the surface of the wafer from the flow channel structure 300 without passing through the disk 202, thereby reducing the influence of the supercritical fluid on the surface temperature of the wafer 600 to be dried above the disk 202, so that the surface temperature of the wafer 600 to be dried above the disk 202 is evenly distributed, thereby reducing the uneven distribution of the isopropyl alcohol liquid film on the wafer surface, thereby improving the wafer yield.

[0048] The wafer tray provided in this embodiment does not limit how to carry the wafers 600 to be dried. The base 100 can carry the wafers 600 to be dried, the tray 202 can also carry the wafers 600 to be dried, and an additional bracket can also be provided to carry the wafers 600 to be dried.

[0049] Furthermore, the wafer tray provided in this embodiment also includes a support leg 400, which is used to support the wafer 600 to be dried. The support leg 400 can be a lifting frame, and the wafer 600 to be dried can be directly placed on the lifting frame. In this embodiment, a wafer ejector pin is preferably used. A first groove is provided on the seat body 100, and the first groove is used to expose the flow channel structure 300 and the tray body 202. The first groove can be a rectangular groove, a circular groove or a groove of other common shapes. The first groove in this embodiment is a semicircular rectangular groove. The cross-sectional area of ​​the first groove is greater than the cross-sectional area of ​​the first through hole. The first through hole is provided at the bottom of the first groove. The support leg 400 is fixedly connected to the bottom of the first groove. The specific fixing means can be bolts or buckles or bonding or integral molding. The wafer 600 to be dried can be placed on the top of the support leg 400. The wafer 600 to be dried has a qualified quality area and an edge removal area surrounding the qualified quality area. The edge removal area can be in contact with the bottom of the support foot 400. The tray body 202 is used to protect the qualified quality area to prevent the supercritical fluid from directly blowing the qualified quality area. Therefore, the cross-sectional area of ​​the wafer 600 to be dried is larger than the cross-sectional area of ​​the tray body 202, and the support foot 400 can be guaranteed to support the edge removal area. Of course, the cross-sectional area of ​​the wafer 600 to be dried can also be smaller than the cross-sectional area of ​​the tray body 202, and only the support foot 400 supporting the wafer needs to be adaptively adjusted.

[0050] The wafer tray provided in this embodiment has a first groove whose depth is greater than the sum of the height of the support foot 400 and the thickness of the wafer 600 to be dried, so as to avoid damage to the pattern on the upper surface of the wafer 600 to be dried by the supercritical fluid during the wafer drying process, thereby reducing the phenomenon of wafer damage during the drying process and further improving the qualified rate of the wafer products.

[0051] In the wafer tray provided in this embodiment, the tray body 202 and the wafer 600 to be dried are spaced apart, that is, there is a gap between the tray body 202 and the wafer 600 to be dried, and the gap can guide the supercritical fluid to pass through so that the supercritical fluid can fully dry the lower surface of the wafer 600 to be dried.

[0052] The wafer tray provided in this embodiment has a second groove on the inner wall of the first through hole, and the upper surface of the second groove has an opening, and one end of the first extension arm 201 can be placed into the second groove from the opening, so that the first extension arm 201 is plugged into the second groove, and the first extension arm 201 is fixedly connected to the bottom of the second groove, and the specific fixing means can be bolt connection, welding, or snap-fitting, and the other end of the first extension arm 201 extends out of the second groove and extends toward the axis of the first through hole, and the other end of the first extension arm 201 is integrally formed or welded, bonded, or snap-fitted with the tray body 202. This enables the first extension arm 201 to support the tray body 202, and enables the tray body 202 to be located directly below the wafer 600 to be dried.

[0053] The wafer tray provided in this embodiment does not limit the number of first extension arms 201. This embodiment uses five first extension arms 201, and the five first extension arms 201 are spaced apart around the periphery of the tray body 202 to provide stable support for the tray body 202 and avoid displacement of the tray body 202 during the drying process.

[0054] The wafer tray provided in this embodiment also includes a second extension arm 500, which is fixed to the base body 100. The specific fixing means can be bolts, clips or integral injection molding. The specific shape of the second extension arm 500 is not limited, and it can be cylindrical or rectangular. The second extension arm 500 extends from the inner wall surface of the first through hole into the first through hole. One of the legs 400 is provided on the upper surface of the second extension. The specific number of the legs 400 is not limited. In this embodiment, the number of the legs 400 is five, and the five legs 400 are spaced apart around the central axis of the tray body 202. The five legs 400 provide uniform support points for the wafers 600 to be dried, thereby ensuring the flatness of the wafers during the drying process.

[0055] The wafer tray provided in this embodiment has a base body 100 including a side panel 101 and a transverse panel 102. The side panel 101 is in the shape of a long strip, and the transverse panel 102 is a semicircular rectangular panel. The transverse panel 102 is fixedly connected to the side panel 101 by specific fixing means such as welding, bolts or snaps. The transverse panel 102 is perpendicular to the side panel 101, and the first groove and the first through hole are both provided on the transverse panel 102. The second extension arm 500 is fixedly connected to the side panel 101.

[0056] The wafer tray provided in this embodiment has a gripping hole 2021 on the tray body 202, which is convenient for the robot to grip the wafer tray. The gripping shape is not limited, and the shape of the gripping hole 2021 is adapted to the robot claw. In this embodiment, the gripping hole 2021 is a circular hole, and the diameter of the gripping hole 2021 is 8-12 mm (millimeter).

[0057] The wafer tray provided in this embodiment has a circular tray body 202, a diameter of the tray body 202 of 265-275 mm (millimeter), a distance between the center of the grabbing through hole 2021 and the center of the tray body 202 of 80-100 mm, a height of 3-4 mm from the upper surface of the base body 100 to the upper surface of the wafer, a thickness of 1-2 mm for the tray body 202, and a thickness of 7-9 mm for the horizontal plate 102.

[0058] Example 2

[0059] The present embodiment provides a wafer drying device, including the wafer tray in Embodiment 1. By adopting the above-mentioned wafer tray, the occurrence of wafer defects is reduced, thereby improving the wafer yield.

[0060] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A wafer tray, characterized in that: include: A base body (100) is provided with a first through hole, and the base body (100) is used to carry a wafer (600) to be dried; A first extension arm (201) extends from the inner wall surface of the first through hole into the first through hole; A tray (202) is disposed in the first through hole and connected to the first extension arm (201), wherein the tray (202) is located below the wafer (600) to be dried; The disc body (202), the first extension arm (201) and the inner wall of the first through hole together form a flow channel structure (300), and the flow channel structure (300) is used for a supercritical fluid to flow through.

2. The wafer tray according to claim 1, characterized in that: Also includes: A support foot (400), wherein a first groove is formed on the base body (100), the first through hole is formed at the bottom of the first groove, the support foot (400) is fixedly connected to the bottom of the first groove, and the support foot (400) is used to abut against the wafer (600) to be dried; The orthographic projection of the wafer (600) to be dried on the base (100) covers the tray (202).

3. The wafer tray according to claim 2, characterized in that: The depth of the first groove is greater than the sum of the height of the support foot (400) and the thickness of the wafer (600) to be dried.

4. The wafer tray according to claim 3, characterized in that: The tray (202) and the wafer (600) to be dried are spaced apart.

5. The wafer tray according to any one of claims 2 to 4, characterized in that: A second groove is formed on the inner wall of the first through hole, one end of the first extension arm (201) is plugged into the second groove, and the other end extends out of the second groove and is fixedly connected to the disk body (202).

6. The wafer tray according to claim 5, characterized in that: A plurality of the first extension arms (201) are provided, and the plurality of the first extension arms (201) are distributed at intervals around the periphery of the disk body (202).

7. The wafer tray according to claim 6, characterized in that: Also includes: A second extension arm (500) extends from the inner wall surface of the first through hole into the first through hole; A plurality of the supporting feet (400) are provided, at least one of the supporting feet (400) is fixedly connected to the second extension arm (500), and a plurality of the supporting feet (400) are distributed at intervals around the central axis of the disk body (202).

8. The wafer tray according to claim 7, characterized in that: The seat body (100) comprises: A side plate (101) fixedly connected to the second extension arm (500); The transverse plate (102) is fixedly connected to the side plate (101), and the transverse plate (102) is perpendicular to the side plate (101), and the transverse plate (102) is provided with the second groove.

9. The wafer tray according to claim 1, characterized in that: The disk body (202) is provided with a grabbing through hole (2021).

10. A wafer drying device, characterized in that: A wafer tray comprising any one of claims 1-9.

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