A rotating chuck for adsorbing fragile wafers

Abstract

The present invention discloses a rotary chuck for adsorbing fragile wafers, which relates to the field of semiconductor technology, and includes a chuck body, a negative pressure device, a rubber ring, a laser probe, a rotating mechanism, a nitrogen spraying module and a main controller, wherein a wafer slot is provided in the middle of the chuck body, a rotating mechanism is provided in the middle of the lower inner wall of the wafer slot, an annular groove is provided on the outer edge of the lower inner wall of the wafer slot, the rubber ring is arranged in the annular groove, a mounting groove is provided on the lower side of the inner peripheral wall of the wafer slot, the laser probe is installed in the mounting groove, a nitrogen spraying module is also arranged in the mounting groove, a negative pressure device and a main controller are arranged inside the chuck body, a plurality of first adsorption holes are provided on the lower inner wall of the wafer slot, the plurality of first adsorption holes are connected to the negative pressure device, the laser probe, the nitrogen spraying module, and the negative pressure device are respectively connected to the main controller. It can adsorb warped and deformed wafers and prevent the wafers from breaking.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, and in particular to a rotary chuck for adsorbing fragile wafers. Background Art

[0002] During the semiconductor manufacturing process, a large amount of stress will inevitably accumulate on the wafer, causing partial or complete warping of the wafer. When the stress exceeds the limit that the wafer can withstand, it may even cause the wafer to break.

[0003] The exposure process requires placing the wafer on the suction cup, fixing it by suction through the vacuum suction holes on the suction cup, and then performing photolithography on the wafer. The suction cup is usually provided with multiple suction holes to better fix the wafer. When the wafer is flat or only slightly warped, the suction cup can absorb the wafer and reduce the warpage of the wafer; but when the wafer is severely deformed, vacuum leakage will occur between the suction cup and the wafer, resulting in the wafer being unable to be adsorbed, resulting in rejection, which greatly affects the yield. Summary of the invention

[0004] The object of the present invention is to provide a rotary chuck for adsorbing fragile wafers, so as to solve the above technical problems.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A rotary chuck for adsorbing fragile wafers, comprising a chuck body, a negative pressure device, a rubber ring, a laser probe, a rotating mechanism, a nitrogen spraying module and a main controller, wherein a wafer slot is provided in the middle of the chuck body, the rotating mechanism is provided in the middle of the lower inner wall of the wafer slot, an annular groove is provided on the outer edge of the lower inner wall of the wafer slot, the rubber ring is arranged in the annular groove, a mounting groove is provided on the lower side of the inner circumferential wall of the wafer slot, the laser probe is installed in the mounting groove, the nitrogen spraying module is also arranged in the mounting groove, the negative pressure device and the main controller are arranged inside the chuck body, a plurality of first adsorption holes are provided on the lower inner wall of the wafer slot, the plurality of first adsorption holes are connected to the negative pressure device, the laser probe, the nitrogen spraying module and the negative pressure device are respectively connected to the main controller.

[0007] Preferably, a stress detection machine is further included, wherein the stress detection machine is arranged in the chuck body and the stress detection machine is signal-connected to the negative pressure device.

[0008] Preferably, the rotating mechanism comprises a rotating bearing.

[0009] Preferably, the nitrogen spraying module comprises four nitrogen spray heads and a nitrogen storage mechanism, wherein each of the nitrogen spray heads is respectively connected to the nitrogen storage mechanism, and the nitrogen storage mechanism is connected to the main controller.

[0010] Preferably, the upper surface of the rubber ring is flush with the upper surface of the wafer slot.

[0011] Preferably, the negative pressure device includes a vacuum generator, a main line and a branch line, wherein each of the branch lines is respectively connected to the main line and one of the first adsorption holes, the main line is connected to the vacuum generator, and the vacuum generator is connected to the main controller.

[0012] As a further preference, the angle between each two adjacent nitrogen nozzles is 45°.

[0013] The above technical solution has the following advantages or beneficial effects:

[0014] (1) In the present invention, the stress of the negative pressure device on the surface of the wafer can be accurately controlled, which can prevent the stress from exceeding the limit of the wafer itself and causing the wafer to break;

[0015] (2) In the present invention, it is possible to detect in advance whether there is an obstacle in the wafer slot. If there is an obstacle between the wafer and the wafer slot, the wafer may be cracked during the process of applying negative pressure to the wafer.

[0016] (3) In the present invention, the position of the wafer in the wafer holder can be adjusted, so that a deformed wafer can be adsorbed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a three-dimensional diagram of a rotary chuck for adsorbing fragile wafers in the present invention;

[0018] Figure 2 is a top view of a rotating chuck for adsorbing fragile wafers in the present invention;

[0019] Figure 3 It is a schematic diagram of the internal structure of the rotary chuck used for adsorbing fragile wafers in the present invention;

[0020] Figure 4 It is a usage state diagram of the rotary chuck used for adsorbing fragile wafers in the present invention.

[0021] In the figure: 1. chuck body; 11. wafer chuck slot; 12. annular groove; 13. mounting groove; 14. first adsorption hole; 15. wafer; 2. negative pressure device; 21. vacuum generator; 22. main pipeline; 23. branch pipeline; 24. air pipe; 3. rubber ring; 31. second adsorption hole; 4. laser probe; 5. rotating mechanism; 6. main controller; 7. stress detection machine; 8. nitrogen nozzle; 9. first suction cup; 10. second suction cup. DETAILED DESCRIPTION

[0022] 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 the embodiments. 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.

[0023] In the description of the present invention, it should be noted that, if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply 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, if the terms "first", "second", "third" appear, they are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0024] 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.

[0025] Figure 1 is a three-dimensional diagram of a rotary chuck for adsorbing fragile wafers in the present invention; Figure 2 is a top view of a rotating chuck for adsorbing fragile wafers in the present invention; Figure 3 It is a schematic diagram of the internal structure of the rotary chuck used for adsorbing fragile wafers in the present invention; Figure 4 This is a diagram of the use state of the rotary chuck used to absorb fragile wafers in the present invention. Figures 1 to 4As shown, a preferred embodiment is shown, which shows a rotary chuck for adsorbing fragile wafers, including a chuck body 1, a negative pressure device 2, a rubber ring 3, a laser probe 4, a rotating mechanism 5, a nitrogen spraying module and a main controller 6, wherein a wafer slot 11 is provided in the middle of the chuck body 1, a rotating mechanism 5 is provided in the middle of the lower inner wall of the wafer slot 11, an annular groove 12 is provided on the outer edge of the lower inner wall of the wafer slot 11, the rubber ring 3 is arranged in the annular groove 12, a mounting groove 13 is provided on the lower side of the inner circumferential wall of the wafer slot 11, the laser probe 4 is installed in the mounting groove 13, a nitrogen spraying module is also provided in the mounting groove 13, a negative pressure device 2 and a main controller 6 are provided inside the chuck body 1, a plurality of first adsorption holes 14 are provided on the lower inner wall of the wafer slot 11, the plurality of first adsorption holes 14 are connected to the negative pressure device 2, the laser probe 4, the nitrogen spraying module, and the negative pressure device 2 are respectively connected to the main controller 6. In this embodiment, as Figure 3 As shown, one side of the mounting groove 13 is connected to the inside of the chuck body 1, and the other side is not connected to the chuck body 1, and the laser probe 4 and the nitrogen spray module are both installed on the inner wall of the other side of the mounting groove 13, wherein the laser probe 4 is used to detect whether there is an obstacle on the lower inner wall of the wafer slot 11. When an obstacle is detected, the main controller 6 (PLC controller) controls the nitrogen spray module to spray nitrogen at a certain angle to blow the obstacle on the lower inner wall of the wafer slot 11 into the chuck body 1. A collection box can be set in the chuck body 1 to collect the blown obstacles. The upper surface of the rotating mechanism 5 in this embodiment is flush with the lower inner wall of the wafer slot 11, and the diameter of the wafer slot 11 is 1mm larger than the diameter of the wafer 15. The longitudinal height of the mounting groove 13 is much smaller than the thickness of the wafer 15. In this embodiment, the rubber ring 3 is used to protect the outer edge of the wafer 15. The outer edge of the wafer 15 is brittle and easy to break. The rubber ring 3 can prevent the outer edge of the wafer 15 from breaking. In this embodiment, the depth of the wafer slot 11 is the same as the thickness of the wafer 15 or the depth of the wafer slot 11 is greater than the thickness of the wafer 15.

[0026] Furthermore, as a preferred embodiment, it also includes a stress detection machine 7, which is arranged in the chuck body 1 and is signal-connected to the negative pressure device 2.

[0027] Further, as a preferred embodiment, the rotating mechanism 5 includes a rotating support. In this embodiment, when the wafer 15 is warped, the rotating support can be used to drive the wafer 15 to rotate so that the warped part of the wafer 15 is adsorbed by the first adsorption hole 14. If adsorption is still not possible, the warped part of the wafer 15 can be pressed by external force so that the warped part of the wafer 15 is adsorbed.

[0028] Further, as a preferred embodiment, the nitrogen spraying module includes four nitrogen spray heads 8 and a nitrogen storage mechanism, wherein each nitrogen spray head 8 is respectively connected to the nitrogen storage mechanism, and the nitrogen storage mechanism is connected to the main controller 6. In this embodiment, the main controller 6 controls the nitrogen storage mechanism to provide nitrogen to the nitrogen spray head 8, and the nitrogen storage mechanism can be a nitrogen storage tank. The nitrogen storage mechanism can be arranged in the chuck body 1, or arranged on the outside of the chuck body 1.

[0029] Further, as a preferred implementation, the upper surface of the rubber ring 3 is flush with the upper surface of the wafer clamping slot 11 .

[0030] Further, as a preferred embodiment, the negative pressure device 2 includes a vacuum generator 21, a main line 22 and a branch line 23, wherein each branch line is respectively connected to the main line 22 and a first adsorption hole 14, the main line 22 is connected to the vacuum generator 21, and the vacuum generator 21 is connected to the main controller 6. The negative pressure device 2 in this embodiment also includes a solenoid valve and a vacuum pressure gauge, wherein the solenoid valve is arranged on the main line 22 for controlling the opening and closing action of the main line 22, and the vacuum pressure gauge is arranged on one side of the vacuum generator 21 for detecting the vacuum pressure value generated by the vacuum generator 21, and feeding back the vacuum pressure value signal to the stress detection machine 7. In this embodiment, a light source assembly and a prism assembly used in conjunction with the stress detection machine 7 are also included, wherein the light source assembly is arranged on the upper side of the wafer slot 11, and the prism assembly is arranged on the lower inner wall of the wafer slot 11. The upper surface of the prism assembly is lower than the plane where the lower inner wall of the wafer slot 11 is located, and the prism assembly is directly opposite to the stress detection machine 7. The light emitted by the light source assembly passes through the wafer 15 and is refracted by the prism assembly. The stress detection machine 7 receives the refracted light and detects the stress value on the surface of the wafer 15 by comparing it with the light that has not been refracted through the glass plate. When the stress value on the surface of the wafer 15 is about to reach the maximum stress value that the wafer 15 itself can bear, the stress detection machine 7 transmits a control signal to the main controller 6, and the main controller 6 controls the vacuum generator 21 to stop working.

[0031] In this embodiment, when the vacuum generator 21 is working, the first adsorption hole 14 generates suction force to adsorb the wafer 15 .

[0032] Further, as a preferred embodiment, the angle between each two adjacent nitrogen nozzles 8 is 45°.

[0033] Furthermore, as a preferred embodiment, the rubber ring 3 is further provided with a second adsorption hole 31 , and the second adsorption hole 31 is connected to the main line 22 via the air pipe 24 . The outer edge of the wafer 15 can be adsorbed by providing the second adsorption hole 31 .

[0034] Further, as a preferred embodiment, it also includes a first suction cup 9 and a second suction cup 10, wherein a first suction cup 9 is respectively provided in each first suction hole 14, and the first suction cup 9 is connected to a respective pipeline, and a second suction cup 10 is respectively provided in each second suction hole 31, and the second suction cup 10 is connected to the air pipe 24. In this embodiment, the first suction cup 9 and the second suction cup 10 are both made of rubber material, and the first suction cup 9 and the second suction cup 10 are provided to facilitate the adsorption of the wafer 15. Among them, the upper surfaces of the first suction cup 9 and the second suction cup 10 are both flush with the lower inner wall of the wafer 15 slot 11.

[0035] The above description is only a preferred embodiment of the present invention, and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A rotary chuck for adsorbing fragile wafers, characterized in that: The invention comprises a chuck body, a negative pressure device, a rubber ring, a laser probe, a rotating mechanism, a nitrogen spraying module and a main controller, wherein a wafer slot is provided in the middle of the chuck body, the rotating mechanism is provided in the middle of the lower inner wall of the wafer slot, an annular groove is provided at the outer edge of the lower inner wall of the wafer slot, the rubber ring is arranged in the annular groove, a mounting groove is provided at the lower side of the inner circumferential wall of the wafer slot, the laser probe is installed in the mounting groove, the nitrogen spraying module is also arranged in the mounting groove, the negative pressure device and the main controller are arranged inside the chuck body, a plurality of first adsorption holes are provided on the lower inner wall of the wafer slot, and the plurality of first adsorption holes are connected to the negative pressure device The laser probe, the nitrogen spraying module, and the negative pressure device are respectively connected to the main controller, and also include a stress detection machine, which is arranged in the chuck body, and the stress detection machine is connected to the negative pressure device signal, the nitrogen spraying module includes four nitrogen spray heads and a nitrogen storage mechanism, wherein each of the nitrogen spray heads is respectively connected to the nitrogen storage mechanism, and the nitrogen storage mechanism is connected to the main controller, the negative pressure device includes a vacuum generator, a main line and a branch line, wherein each of the branch lines is respectively connected to the main line and one of the first adsorption holes, the main line is connected to the vacuum generator, and the vacuum generator is connected to the main controller; The rubber ring is also provided with a second adsorption hole, and the second adsorption hole is connected to the main pipeline through an air pipe; It also includes a first suction cup and a second suction cup, wherein a first suction cup is respectively provided in each of the first suction holes, and the first suction cup is connected to the branch pipeline, and a second suction cup is respectively provided in each of the second suction holes, and the second suction cup is connected to the air pipe.

2. The rotary chuck for adsorbing fragile wafers according to claim 1, characterized in that: The rotating mechanism includes a rotating bearing.

3. The rotary chuck for adsorbing fragile wafers according to claim 1, characterized in that: The upper surface of the rubber ring is flush with the upper surface of the wafer clamping slot.

4. The rotary chuck for adsorbing fragile wafers according to claim 1, characterized in that: The included angle between each two adjacent nitrogen nozzles is 45°.

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