Device for detecting thickness of semiconductor wafer

Abstract

The invention provides a semiconductor wafer thickness detection device, and relates to the technical field of semiconductor wafer processing. According to the semiconductor wafer thickness detection device, by designing the air cylinder, the first moving mechanism and the placing assembly, the wafer can form negative pressure in the cavity through the micro air pump, so that the wafer is adsorbed on the surface of the placing plate, compared with a traditional clamping mechanism, the situation that the surface of the wafer is easily scratched by the clamping mechanism is avoided, and meanwhile, the detection efficiency is improved. The air cylinder and the first servo motor can respectively drive the detection head to move from two horizontal directions, so that the thicknesses of different positions of the wafer can be detected, whether the thicknesses of the whole wafer are the same or not and whether the maximum thickness and the minimum thickness of the wafer are qualified or not can be distinguished, the detection result is more accurate, and by designing a second moving mechanism and a movable plate, the detection efficiency is improved. And the three groups of placing assemblies are arranged above the movable plate for placing the wafers, and when a single group of wafers are detected in cooperation with the reciprocating motion of the movable plate, the wafers can be loaded on the other placing assemblies, so that the efficiency is higher.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor wafer processing, in particular to a device for detecting the thickness of a semiconductor wafer. Background Art

[0002] Semiconductor wafers are the basic materials used to manufacture semiconductor devices. They are usually single crystal or polycrystalline materials made through highly purified and crystal growth technology. Semiconductor wafers play a vital role in the semiconductor manufacturing process, and their purity and quality directly affect the performance and reliability of the final semiconductor device. These wafers are usually thin and solid sheet structures, on which the manufacturing process of various semiconductor devices and circuits is carried out, and thus they are widely used in electronic devices such as computers, mobile phones, televisions, etc. The manufacture and application of semiconductor wafers demonstrate their core position in modern electronic technology and reflect their importance in the information age.

[0003] In the prior art, when detecting the thickness of semiconductor wafers, there are generally two methods: contact and non-contact. The contact method requires contact with the wafer, and the contact measurement accuracy is low and may cause damage to the wafer. At the same time, it generally measures the overall thickness of the wafer, and cannot know the thickness of each position of the wafer, and cannot distinguish whether the thickness of the wafer as a whole is the same; in the non-contact measurement method, during the detection process, the wafer cannot be positioned well, or it is directly placed on the detection plane without limiting. At this time, once the wafer is displaced, it can cause inaccurate positioning, affecting its detection, or a conventional clamping mechanism is used for positioning, and the clamping mechanism is very likely to cause scratches on the surface of the wafer, which ultimately affects the quality of the wafer.

[0004] Therefore, we have developed a new device for detecting the thickness of semiconductor wafers. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the present invention provides a device for detecting the thickness of a semiconductor wafer, which solves the problems in the prior art of detecting the thickness of a semiconductor wafer, namely, a contact method and a non-contact method. The contact method requires contact with the wafer, has low measurement accuracy and may damage the wafer. At the same time, what is measured is generally the overall thickness of the wafer, and the thickness of each position of the wafer cannot be known, and it is impossible to distinguish whether the overall thickness of the wafer is the same. In the non-contact measurement method, during the detection process, the wafer cannot be well positioned, or it is directly placed on a detection plane without limiting. At this time, once the wafer is displaced, inaccurate positioning may occur, affecting its detection. Alternatively, a conventional clamping mechanism is used for positioning, and the clamping mechanism is very likely to cause scratches on the surface of the wafer, thereby ultimately affecting the quality of the wafer.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: A semiconductor wafer thickness detection device, comprising a chassis, a mounting frame is fixedly connected to one end of the upper surface of the chassis, a cylinder is fixedly installed on the inner side of the mounting frame, a rectangular mounting frame is fixedly connected to the piston end of the cylinder, a first moving mechanism is installed on the inner side of the rectangular mounting frame, and a detection head is fixedly connected to one end of the first moving mechanism;

[0009] A workbench is fixedly connected to the top of one side of the outer surface of the chassis, a second moving mechanism is installed on one side of the outer surface of the workbench, one end of the second moving mechanism is fixedly connected to a movable plate, and the lower surface of the movable plate is slidably connected to the upper surface of the workbench, and three groups of placement components are fixedly connected to the upper surface of the movable plate.

[0010] Preferably, the first moving mechanism includes a first ball screw rotatably connected to the inner side of a rectangular mounting frame, the outer surface of the first ball screw is threadedly sleeved with a first slider, the outer surface of the first slider is slidably connected to the inner side of the rectangular mounting frame, and one end of the first slider is fixedly connected to the bottom of one side of the outer surface of the detection head.

[0011] Preferably, the second moving mechanism includes two fixed seats symmetrically fixedly connected to one side of the outer surface of the workbench, and the opposite sides of the two fixed seats are rotatably connected with a second ball screw. The outer surface of the second ball screw is threadedly connected with a second slider, one side of the outer surface of the second slider is slidably connected to the workbench, and the second slider and the opposite side of the movable plate are commonly fixedly connected with a connecting rod.

[0012] Preferably, the placement assembly includes a placement rack fixedly connected to the upper surface of the movable plate, and a placement plate is fixedly connected to the inner side of the placement rack, a plurality of ventilation holes are provided on the side wall of the placement plate, a cavity is provided on the inner side of the placement rack, a connecting pipe is fixedly connected to the bottom of the placement rack, the connecting pipe passes through and is fixedly connected to the bottom of the placement rack, and a micro air pump is fixedly installed at one end of the connecting pipe.

[0013] Preferably, a first servo motor is fixedly mounted on one end of the rectangular mounting frame, and an output shaft of the first servo motor passes through and extends into the interior of the mounting frame and is fixedly connected to one end of the first ball screw.

[0014] Preferably, a second servo motor is fixedly mounted on one side of the outer surface of a single fixing seat, and an output shaft of the second servo motor extends through the inner side of the fixing seat and is fixedly connected to one end of the second ball screw.

[0015] Preferably, a side of the mounting frame close to the first servo motor is provided with a clearance groove matching the first servo motor.

[0016] Preferably, supporting legs are fixedly connected to the lower surface of the chassis on all four sides, a control box is fixedly mounted on one end of the upper surface of the chassis, and a plurality of control buttons are fixedly mounted on the front of the control box.

[0017] Preferably, door panels are symmetrically hinged on the front of the chassis, and handles are fixedly connected to the front of both door panels.

[0018] Preferably, an infrared rangefinder is fixedly installed inside the detection head, a wire is fixedly connected to the top of the infrared rangefinder, and one end of the wire extends through the top of the detection head and is fixedly connected to a power connection line.

[0019] (III) Beneficial effects

[0020] The present invention provides a device for detecting the thickness of a semiconductor wafer, which has the following beneficial effects:

[0021] 1. The semiconductor wafer thickness detection device, through the design of the cylinder, the first moving mechanism and the placement component, the wafer can form a negative pressure in the cavity through the micro air pump, so that the wafer is adsorbed on the surface of the placement plate. Compared with the traditional clamping mechanism, it avoids the situation that it is easy to scratch the surface of the wafer. At the same time, the cylinder and the first servo motor can drive the detection head to move in two horizontal directions respectively, so as to detect the thickness of different positions of the wafer, and can distinguish whether the overall thickness of the wafer is the same, and whether the maximum thickness and minimum thickness of the wafer are qualified, so that the detection result is more accurate.

[0022] 2. The semiconductor wafer thickness detection device is designed with a second moving mechanism and a movable plate. Three groups of placement components are arranged above the movable plate to place the wafers. The movable plate moves back and forth to detect the wafers above the three groups of placement components in turn. When a single group of wafers is being detected, other placement components can be installed on the wafers, and the efficiency of the overall device is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a three-dimensional diagram of the overall structure of the present invention;

[0024] Figure 2 is a cross-sectional perspective view of the detection head of the present invention;

[0025] Figure 3 A three-dimensional diagram of a placement rack of the present invention;

[0026] Figure 4 It is a cross-sectional perspective view of the placement rack of the present invention;

[0027] Figure 5 It is a schematic diagram of the connection between the cylinder and the first moving mechanism of the present invention;

[0028] Figure 6 For the present invention Figure 1 Enlarged view of point A in the middle.

[0029] Among them, 1. chassis; 2. door panel; 3. handle; 4. support leg; 5. control box; 6. control button; 7. mounting frame; 8. cylinder; 9. rectangular mounting frame; 10. first servo motor; 11. first ball screw; 12. first slider; 13. clearance groove; 14. detection head; 15. infrared rangefinder; 16. wire; 17. power connection line; 18. workbench; 19. fixed seat; 20. second ball screw; 21. second servo motor; 22. second slider; 23. connecting rod; 24. movable plate; 25. placement frame; 26. cavity; 27. placement plate; 28. vent; 29. ​​connecting pipe; 30. micro air pump. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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.

[0031] Examples, such as Figure 1 - Figure 6 As shown, an embodiment of the present invention provides a semiconductor wafer thickness detection device, comprising a chassis 1, a mounting frame 7 is fixedly connected to one end of the upper surface of the chassis 1, a cylinder 8 is fixedly installed on the inner side of the mounting frame 7, a rectangular mounting frame 9 is fixedly connected to the piston end of the cylinder 8, a first moving mechanism is installed on the inner side of the rectangular mounting frame 9, and a detection head 14 is fixedly connected to one end of the first moving mechanism, and the extension and contraction of the piston end of the cylinder 8 can drive the displacement of the detection head 14 in the horizontal direction, so as to facilitate the detection head 14 to detect the wafer thickness at different positions;

[0032] A workbench 18 is fixedly connected to the top of one side of the outer surface of the chassis 1, and a second moving mechanism is installed on one side of the outer surface of the workbench 18. A movable plate 24 is fixedly connected to one end of the second moving mechanism, and the lower surface of the movable plate 24 is slidably connected to the upper surface of the workbench 18, and three groups of placement components are fixedly connected to the upper surface of the movable plate 24.

[0033] like Figure 5As shown, the first moving mechanism includes a first ball screw 11 rotatably connected to the inner side of the rectangular mounting frame 9, the outer surface of the first ball screw 11 is sleeved with a first slider 12 threadedly connected, the outer surface of the first slider 12 is slidably connected to the inner side of the rectangular mounting frame 9, and one end of the first slider 12 is fixedly connected to the bottom of one side of the outer surface of the detection head 14. When the first ball screw 11 rotates, the first slider 12 will slide along the inner side of the rectangular mounting frame 9, thereby changing the horizontal position of the detection head 14, making it convenient for the detection head 14 to measure the thickness of the chip at different positions.

[0034] like Figure 1 As shown, the second moving mechanism includes two fixed seats 19 symmetrically fixedly connected to one side of the outer surface of the workbench 18, and the opposite sides of the two fixed seats 19 are rotatably connected with a second ball screw 20. The outer surface of the second ball screw 20 is threadedly connected with a second slider 22. One side of the outer surface of the second slider 22 is slidably connected to the workbench 18, and the second slider 22 and the opposite side of the movable plate 24 are commonly fixedly connected with a connecting rod 23. When the second ball screw 20 rotates, the second slider 22 will slide along one side of the outer surface of the workbench 18, thereby changing the horizontal position of the movable plate 24, so that different placement components are moved to the bottom of the detection head 14, so that chip detection can be carried out continuously with high efficiency.

[0035] Correspondingly, a second servo motor 21 is fixedly installed on one side of the outer surface of the single fixed seat 19, and the output shaft of the second servo motor 21 extends through the inner side of the fixed seat 19 and is fixedly connected to one end of the second ball screw 20. The operation of the second servo motor 21 can drive the rotation of the second ball screw 20, thereby realizing the movement effect of the above-mentioned second moving mechanism on the movable plate 24.

[0036] like Figure 3 and Figure 4 As shown, the placement component includes a placement rack 25 fixedly connected to the upper surface of the movable plate 24, and a placement plate 27 is fixedly connected to the inner side of the placement rack 25, and a plurality of ventilation holes 28 are opened on the side wall of the placement plate 27, wherein the ventilation holes 28 are arranged in a circular shape on the surface of the placement plate 27, so as to facilitate the placement and fixation of the wafer, and a cavity 26 is opened on the inner side of the placement rack 25, and a connecting pipe 29 is fixedly connected to the bottom of the cavity 26, and the connecting pipe 29 passes through and is fixedly connected to the bottom of the placement rack 25, and a micro air pump 30 is fixedly installed at one end of the connecting pipe 29, and an air inlet pipe of the micro air pump 30 is connected to the connecting pipe 29. When the micro air pump 30 is started, the air in the cavity 26 can be sucked out through the connecting pipe 29. At this time, a negative pressure is formed between the cavity and the placement plate 27, so that the wafer placed above the ventilation hole 28 of the placement plate 27 can be sucked, thereby fixing the position of the wafer to prevent the wafer from shifting when the movable plate 24 moves.

[0037] like Figure 6 As shown, a first servo motor 10 is fixedly mounted at one end of the rectangular mounting frame 9, and an output shaft of the first servo motor 10 penetrates and extends into the interior of the mounting frame 7 and is fixedly connected to one end of the first ball screw 11, wherein a clearance groove 13 matching the first servo motor 10 is provided on one side of the mounting frame 7 close to the first servo motor 10, so that the first servo motor 10 can be avoided to avoid damage when it is displaced after being pushed by the cylinder 8;

[0038] Correspondingly, the operation of the first servo motor 10 can drive the first ball screw 11 to rotate, thereby achieving the movement effect of the first moving mechanism on the detection head 14 .

[0039] like Figure 1 As shown, support legs 4 are fixedly connected to the lower surface of the chassis 1 on all sides, a control box 5 is fixedly installed on one end of the upper surface of the chassis 1, a plurality of control buttons 6 are fixedly installed on the front of the control box 5, and the control box 5 is electrically connected to the first servo motor 10, the second servo motor 21, the cylinder 8 and the micro air pump 30 respectively, and the above-mentioned electrical equipment can be controlled by the control buttons of the control box 5.

[0040] like Figure 1 As shown, the front of the chassis 1 is symmetrically hinged with door panels 2, and the front of the two door panels 2 are fixedly connected with handles 3. The interior of the chassis 1 can be used to place related mechanical parts or tools required for repairing equipment, and the door panels 2 play the role of isolating an independent space. The door panels 2 can be opened through the handles 3 to obtain the tools.

[0041] like Figure 2 As shown, an infrared rangefinder 15 is fixedly installed inside the detection head 14, and a wire 16 is fixedly connected to the top of the infrared rangefinder 15. One end of the wire 16 extends through the top of the detection head 14 and is fixedly connected to a power connection line 17. The infrared rangefinder 15 can detect the distance between the top of the wafer and the infrared rangefinder 15. Relatively speaking, the distance between the infrared rangefinder 15 and the placement plate 27 is fixed and measured in advance. The difference between the two can be calculated to obtain the thickness of the wafer.

[0042] Working principle: First, common negative pressure adsorption loading components (which are often used for loading or transportation in automated production lines in the prior art) can be configured at both ends of the movable plate 24. In the initial state, only one end of the movable plate 24 is directly below the detection head 14, while the placement components in the middle and the other end can be loaded through the above-mentioned loading components, and the chip is placed directly above the vent 28 of the placement plate 27, and the vent 28 is blocked by the chip. Then, when it is officially working, the second servo motor 21 is braked and started, which can drive the rotation of the second ball screw 20. When the second ball screw 20 rotates, it will cause the second slider 22 to slide along one side of the outer surface of the workbench 18, thereby changing the horizontal position of the movable plate 24. , so that the middle placement component is moved to the bottom of the detection head 14, so that the wafer inside it is first tested for thickness, and then the placement component at one end of the movable plate 24 carrying the wafer is moved to the bottom of the detection head 14 for testing. At this time, the original middle placement component and the empty placement component at the other end can be loaded with another loading component, so that the wafer is placed on the placement plate 27, and then under the action of the second ball screw 20, it is placed under the detection head 14 again in the opposite direction for testing, thereby achieving the effect of continuous wafer testing, and the loading process of the wafer does not affect the testing efficiency, which is more efficient as a whole (the movable plate 24 remains stationary when the wafer is testing the thickness, that is, the second servo motor 21 is in a paused state at this time);

[0043] Specifically, when the wafer is being inspected, the infrared rangefinder 15 can detect the distance between the top of the wafer and the infrared rangefinder 15. Relatively speaking, the distance between the infrared rangefinder 15 and the placement plate 27 is fixed and measured in advance. The difference between the two can be calculated to obtain the thickness of the wafer. In addition, the position of the detection head 14 can be changed by the cylinder 8 and the first servo motor 10, thereby changing the position of the infrared rangefinder 15, so that the infrared rangefinder 15 can measure the thickness of different positions of the wafer, and can determine whether the overall thickness of the wafer is the same, and whether the maximum thickness and minimum thickness of the wafer are qualified, so that the detection result is more accurate.

[0044] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for detecting the thickness of a semiconductor wafer, comprising a chassis (1), characterized in that: A mounting frame (7) is fixedly connected to one end of the upper surface of the chassis (1); a cylinder (8) is fixedly installed on the inner side of the mounting frame (7); a piston end of the cylinder (8) is fixedly connected to a rectangular mounting frame (9); a first moving mechanism is installed on the inner side of the rectangular mounting frame (9); and a detection head (14) is fixedly connected to one end of the first moving mechanism; A workbench (18) is fixedly connected to the top of one side of the outer surface of the chassis (1), a second moving mechanism is installed on one side of the outer surface of the workbench (18), one end of the second moving mechanism is fixedly connected to a movable plate (24), and the lower surface of the movable plate (24) is slidably connected to the upper surface of the workbench (18), and the upper surface of the movable plate (24) is fixedly connected to three groups of placement components.

2. A semiconductor wafer thickness detection device according to claim 1, characterized in that: The first moving mechanism comprises a first ball screw (11) rotatably connected to the inner side of a rectangular mounting frame (9); the outer surface of the first ball screw (11) is sleeved with a first slider (12) threadedly connected; the outer surface of the first slider (12) is slidably connected to the inner side of the rectangular mounting frame (9), and one end of the first slider (12) is fixedly connected to the bottom of one side of the outer surface of the detection head (14).

3. A semiconductor wafer thickness detection device according to claim 2, characterized in that: The second moving mechanism comprises two fixed seats (19) symmetrically fixedly connected to one side of the outer surface of the workbench (18); the opposite sides of the two fixed seats (19) are rotatably connected to a second ball screw (20); the outer surface of the second ball screw (20) is threadedly connected to a second slider (22); one side of the outer surface of the second slider (22) is slidably connected to the workbench (18); and the second slider (22) and the opposite side of the movable plate (24) are fixedly connected to a connecting rod (23).

4. A semiconductor wafer thickness detection device according to claim 3, characterized in that: The placement assembly comprises a placement rack (25) fixedly connected to the upper surface of the movable plate (24), and a placement plate (27) is fixedly connected to the inner side of the placement rack (25), a side wall of the placement plate (27) is provided with a plurality of ventilation holes (28), a cavity (26) is provided on the inner side of the placement rack (25), a connecting pipe (29) is fixedly connected to the bottom of the placement rack (25), the connecting pipe (29) passes through and is fixedly connected to the bottom of the placement rack (25), and a micro air pump (30) is fixedly installed at one end of the connecting pipe (29).

5. A semiconductor wafer thickness detection device according to claim 4, characterized in that: A first servo motor (10) is fixedly mounted on one end of the rectangular mounting frame (9); an output shaft of the first servo motor (10) penetrates and extends into the interior of the mounting frame (7) and is fixedly connected to one end of a first ball screw (11).

6. A semiconductor wafer thickness detection device according to claim 5, characterized in that: A second servo motor (21) is fixedly mounted on one side of the outer surface of a single fixed seat (19), and an output shaft of the second servo motor (21) extends through the inner side of the fixed seat (19) and is fixedly connected to one end of the second ball screw (20).

7. A semiconductor wafer thickness detection device according to claim 6, characterized in that: A clearance groove (13) matching the first servo motor (10) is provided on one side of the mounting frame (7) close to the first servo motor (10).

8. The device for detecting the thickness of a semiconductor wafer according to claim 7, characterized in that: The lower surface of the chassis (1) is fixedly connected to support legs (4) on all sides, a control box (5) is fixedly mounted on one end of the upper surface of the chassis (1), and a plurality of control buttons (6) are fixedly mounted on the front of the control box (5).

9. A semiconductor wafer thickness detection device according to claim 8, characterized in that: The front of the chassis (1) is symmetrically hinged with door panels (2), and the fronts of the two door panels (2) are fixedly connected with handles (3).

10. The device for detecting the thickness of a semiconductor wafer according to claim 9, characterized in that: An infrared rangefinder (15) is fixedly installed inside the detection head (14), a wire (16) is fixedly connected to the top of the infrared rangefinder (15), and one end of the wire (16) extends through the top of the detection head (14) and is fixedly connected to a power connection line (17).

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