A wafer suction cup

Abstract

The present invention discloses a wafer suction cup, including a disc body, wherein the disc body includes an adsorption surface, wherein the adsorption surface is a plane, and the adsorption surface is in contact with the wafer; a central circular hole connected to an air pipe is provided in the center of the adsorption surface, and a plurality of concentric annular grooves are provided from the central circular hole to the outside at intervals, and N grooves with "triangular" cross-sections are evenly distributed radially from the central circular hole, and the triangular grooves intersect with all the annular grooves; the disc body is bonded to a metal tray, and the air pipe is fixed on the metal tray and connected to the central circular hole. Advantages: The wafer suction cup of the present invention uses a metal tray as a rigid support, which solves the problems of ordinary suction cups, such as toilet pumps, which do not have rigid support, and are prone to flattening of the suction cup and failure to adsorb the edge when the suction force is large and the suction speed is fast; at the same time, the suction channel is designed using the equal flow principle, so that the resistance is minimized during suction, and thus the speed is fast and the pressure is high.

Description

Technical Field

[0001] The invention relates to a wafer suction cup. Background Art

[0002] In the semiconductor chip manufacturing process, semiconductor silicon wafers (wafers) need to go through multiple processes and need to be moved between them, which are usually done by suction cups. The structural design of the suction cup will affect the adsorption force and adsorption speed, thus affecting whether it will fall off during the movement process.

[0003] The suction force of the suction cup relies on the sudden decrease in air pressure, which is transmitted through the flow of gas. The best state for fluid pipeline flow is equal flow rate, in which the fluid flows fast and the pressure is uniform; while in unequal flow rate, the flow of the fluid will be hindered by the pipe wall, the pressure becomes uneven, and the transmission of pressure in the pipeline is affected. Summary of the invention

[0004] The technical problem to be solved by the present invention is: how to use the equal flow principle to design a wafer suction cup so that the wafer can be adsorbed quickly and is not easy to fall off.

[0005] The technical solutions adopted are as follows:

[0006] A wafer suction cup comprises a cup body, the cup body comprises an adsorption surface, the adsorption surface is a plane, and the adsorption surface is in contact with the wafer; a central circular hole for communicating with an air pipe is provided at the center of the adsorption surface, a plurality of concentric annular grooves are provided at intervals outward from the central circular hole, a plurality of grooves with "triangular" cross-sections are evenly distributed radially from the central circular hole, and the triangular grooves intersect with all the annular grooves;

[0007] Among them, the inner arc length of the triangular groove in the annular groove is A, and the length of the arc line of the triangular interface bottom of the triangular groove is known to be According to the proportional relationship between arc length and radius, we can know that:

[0008] (1)

[0009] (2)

[0010] R1 is the radius of the adsorption surface, R0 is the radius of the central hole, R is the radius of the circular auxiliary line concentric with the central hole on the adsorption surface, N is the number of triangular grooves, R0<R<R1;

[0011] According to the equal flow principle, the flow from the triangular groove to the annular groove is equal, and the width of the annular groove The inner arc length of the triangular groove in the annular groove is A, that is, :

[0012] (3).

[0013] In a further preferred embodiment of the technical solution of the present invention, the plate body is bonded to a metal tray, and the air pipe is fixed on the metal tray and connected to the central circular hole. The metal tray serves as a rigid support, which solves the problem that ordinary suction cups, such as toilet pumps, do not have a rigid support and are prone to flattening and the edge cannot be adsorbed when the suction force is large and the air extraction speed is fast. The flexible air pipe is connected to the metal tray through an air nozzle, and the air pipe or suction cup can be replaced.

[0014] In a further preferred embodiment of the technical solution of the present invention, when the number of the annular grooves is M, :

[0015] (4).

[0016] In a further preferred embodiment of the technical solution of the present invention, one vertex of the triangular groove extends to the edge of the adsorption surface, so that the suction cup area can be maximized.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. A wafer suction cup of the present invention uses a metal tray as a rigid support, which solves the problem that an ordinary suction cup, such as a toilet pump, has no rigid support and is prone to flattening and the edge cannot be adsorbed when the suction force is large and the suction speed is fast. At the same time, the suction channel is designed using the equal flow principle to minimize the resistance during suction, thereby achieving fast speed and high pressure.

[0019] 2. A wafer suction cup of the present invention is based on a wafer suction cup with equal air flow, so that the wafer suction cup has a fast adsorption speed, a strong adsorption force, and is not easy to fall when moving the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a front view of the wafer suction cup of the present invention after absorbing the wafer;

[0021] Figure 2 It is a schematic diagram of the groove design principle of the adsorption surface of the wafer suction cup of the present invention;

[0022] Figure 3 A relationship diagram between variables A and R in the groove design principle of the adsorption surface of the wafer chuck of the present invention;

[0023] Figure 4 Schematic diagram of the groove structure of the adsorption surface of the wafer chuck of this embodiment;

[0024] Figure 5 This is a three-dimensional perspective view of the wafer suction cup and the wafer after being adsorbed in this embodiment;

[0025] Among them: 1-disk body, 2-annular groove, 3-triangular groove, 4-circular auxiliary line, 5-metal tray, 6-air pipe, 7-wafer to be tested, 8-center circular hole. DETAILED DESCRIPTION

[0026] The technical solution of the present invention is described in detail below, but the protection scope of the present invention is not limited to the embodiments.

[0027] To make the content of the present invention more clearly understood, the following Figure 1 -Attached Figure 5 The specific implementation manner is further described.

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] like Figure 1 As shown, this embodiment is a wafer suction cup, which is designed by using the equal flow principle, so that the wafer can be adsorbed quickly and is not easy to fall off.

[0030] like Figure 1 As shown, the wafer suction cup of this embodiment includes a cup body 1. In this embodiment, the material of the cup body 1 is soft material such as rubber, resin, silicone, etc.

[0031] When in use, the tray body 1 is fixed on the metal tray 5 by gluing, the air pipe 6 is fixed on the metal tray 5 and communicates with the central circular hole 8 , and the air pipe 6 is located in the circular hole in the center of the metal tray 5 .

[0032] like Figure 2 As shown, the disc body includes an adsorption surface, which is a plane and fits the contact surface of the wafer. A central circular hole 8 for communicating with an air pipe 6 is provided at the center of the adsorption surface, and multiple concentric annular grooves 2 are provided at intervals outward from the central circular hole 8. Multiple grooves with "triangular" cross-sections are evenly distributed radially from the central circular hole 8, and the triangular grooves 3 intersect with all the annular grooves 2.

[0033] The inner arc length of the triangular groove 3 in the annular groove 2 is A, which is the width of the triangular notch of the triangular groove 3 in the annular groove 2. The length of the arc line of the bottom surface of the triangular interface of the triangular groove 3 is According to the proportional relationship between arc length and radius, we can know that:

[0034] (1)

[0035] (2)

[0036] R1 is the radius of the adsorption surface, R0 is the radius of the central circular hole 8, R is the radius of the circular auxiliary line 4 concentric with the central circular hole 8 on the adsorption surface, N is the number of triangular grooves 3, R0<R<R1. It should be noted that the circular auxiliary line 4 is used to indicate that the auxiliary line can be moved, and it is not an actual edge.

[0037] According to the equal flow principle, the flow from the triangular groove 3 to the annular groove 2 is equal, and the width of the annular groove 2 is The inner arc length of the triangular groove 3 in the annular groove 2 is A, that is, :

[0038] (3)

[0039] The relationship between the specific structural parameters A and R of the groove can be calculated by formula (3), as follows: Figure 3 shown.

[0040] When the number of annular grooves 2 is M, :

[0041] (4). Specific embodiments

[0043] The technical solution of the present invention is further described below with an example. Figure 4 and Figure 5 As shown, the suction cup material of this embodiment is made of soft materials such as rubber, resin, and silicone.

[0044] The wafer suction cup has a diameter of 8 inches and is suitable for 8-inch wafers. The suction surface of the cup has a groove structure, which has six triangular grooves 3 and five annular grooves 2 radially radiating from the central circular hole 8. The diameter of the central circular hole 8 is 20 mm, and the groove depths of the triangular grooves 3 and the annular grooves 2 are 1 mm.

[0045] According to formulas (1), (2), (3), and (4), the radii of the five annular grooves 2 are 8 mm, 12 mm, 16 mm, 20 mm, and 24 mm, respectively. The widths of the five annular grooves 2 are 1.1 mm, 0.8 mm, 0.6 mm, 0.3 mm, and 0.1 mm, respectively.

[0046] When sucking the wafer, the wafer suction cup of this embodiment is gently pressed on the wafer to be tested 7, and the gas is quickly pumped out. The gas flows out through the central circular hole 8, the triangular groove 3 and the annular groove 2, and the air pressure is reduced. Under the pressure of the external atmospheric pressure, the wafer is adsorbed on the adsorption surface of the disc.

[0047] When releasing the wafer, air is inflated through the air pipe 6, and the gas flows in through the central circular hole 8, the triangular groove 3 and the annular groove 2, and the air pressure increases until the air pressure in the suction cup is equal to the atmospheric pressure, and the crystal is separated from the suction cup.

[0048] The above embodiments are only for illustrating the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the present invention.

Claims

1. A wafer chuck, characterized in that: The disk comprises a disk body, the disk body comprising an adsorption surface, the adsorption surface being a plane, and the adsorption surface is in contact with the wafer contact surface; a central circular hole (8) communicating with an air pipe is provided at the center of the adsorption surface, a plurality of concentric annular grooves (2) are provided at intervals outward from the central circular hole (8), N grooves with "triangular" cross-sections are evenly distributed radially from the central circular hole (8), and the triangular grooves (3) intersect with all the annular grooves (2); The inner arc length of the triangular groove (3) in the annular groove (2) is A. It is known that the length of the arc line of the bottom surface of the triangular interface of the triangular groove (3) is: According to the proportional relationship between arc length and radius, we can know that: （1） （2） R1 is the radius of the adsorption surface, R0 is the radius of the central circular hole (8), R is the radius of a circular auxiliary line (4) concentric with the central circular hole (8) on the adsorption surface, N is the number of triangular grooves (3), R0<R<R1; According to the equal flow principle, the flow rate from the triangular groove (3) into the annular groove (2) is equal, and the width of the annular groove (2) is is equal to the inner arc length of the triangular groove (3) in the annular groove (2) is A, that is, : （3）。 2. The wafer chuck according to claim 1, characterized in that: The disc body is bonded to a metal tray (5), and the air pipe (6) is fixed on the metal tray (5) and connected to the central circular hole (8).

3. The wafer chuck according to claim 1, characterized in that: When the number of annular grooves (2) is M, then : （4）。 4. The wafer chuck according to claim 1, characterized in that: One vertex of the triangular groove (3) extends to the edge of the adsorption surface.

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