Cleaning device for metal ion residues after cutting of semiconductor silicon wafers

Abstract

The utility model discloses a semiconductor silicon wafer cutting postmetal ion residual cleaning device relates to the technical field of semiconductor production, including the cleaning machine cabinet body and the workstation of installing in the cleaning machine cabinet body, the inside of cleaning machine cabinet body is provided with transfer mechanism, and the flushing head on the caustic washing tank is matched with alkaline liquid pipe, drain pipe, solves the traditional semiconductor silicon wafer after still needing to be transferred to the water washing procedure and carries out water washing after the alkaline solution cleaning, leads to the problem of semiconductor silicon wafer overall cleaning time-consuming longer, and the water washing and drying two processes are integrated together through the alkaline solution cleaning process of the application, solve the traditional semiconductor silicon wafer cleaning to need to pass through acid and alkali cleaning, water washing, dry, not only occupy too much space, and semiconductor silicon wafer needs frequently to transfer also increased the problem of secondary pollution risk, is favorable to the practicality of semiconductor silicon wafer cleaning device improves.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing technology, specifically to a cleaning device for residual metal ions after semiconductor silicon wafer cutting. Background Technology

[0002] In semiconductor manufacturing, the silicon wafer cutting process requires the use of tools such as diamond wire saws and cutting fluids, which can easily introduce residual metal ions such as Fe, Cu, and Ni. These residues can lead to device leakage and reduced yield in subsequent processes. Therefore, semiconductor silicon wafers need to be cleaned after cutting. Traditional semiconductor silicon wafers, after being ultrasonically cleaned with acid and alkali solutions, need to be transferred to a water rinsing process to thoroughly remove residual chemical solutions and contaminants from the surface of the silicon wafers. This process of transferring the silicon wafers from the acid and alkali cleaning process to the water rinsing process makes the overall cleaning of semiconductor silicon wafers time-consuming and results in low work efficiency. Furthermore, traditional semiconductor silicon wafer cleaning requires acid and alkali cleaning, water rinsing, and drying. Each process requires additional setup, which not only occupies too much space, but also increases the risk of recontamination due to the frequent transfer of semiconductor silicon wafers. In addition, setting up these processes also requires additional costs, and a lot of time is spent on silicon wafer transfer, resulting in poor practical performance of semiconductor silicon wafer cleaning equipment. Utility Model Content

[0003] To address the above problems, this invention provides a cleaning device for residual metal ions after semiconductor silicon wafer cutting, thus solving the aforementioned issues.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a cleaning device for residual metal ions after semiconductor silicon wafer cutting, comprising a cleaning cabinet and a workbench installed in the cleaning cabinet, wherein a transfer mechanism is provided inside the cleaning cabinet, and an acid washing tank and an alkaline washing tank are connected to the workbench. The top of the alkaline washing tank is connected to two fixed seats. Each of the two fixed seats is connected to several flushing heads. One end of each flushing head is connected to a diversion pipe. One side of the diversion pipe is connected to a conveying pipe. The conveying pipe passes through the workbench and is connected to an external water supply device. Two support plates are connected to the top of each of the two fixed bases. An air knife tube is provided in the two support plates. Several nitrogen nozzles are connected to the outside of the air knife tube. A nitrogen supply pipe is connected to one side of the air knife tube. Rotary shafts are connected to both ends of the air knife tube. The outside of the rotating shafts is rotatably connected to the support plates. A synchronous rotation mechanism is provided on one side of the two air knife tubes.

[0005] Preferably, one side of the alkaline washing tank is connected to a plurality of alkaline washing liquid pipes, the plurality of alkaline washing liquid pipes including drain pipes and infusion pipes, the plurality of drain pipes and infusion pipes being distributed at intervals, and one side of the alkaline washing tank is connected to a plurality of drain pipes.

[0006] Preferably, the synchronous rotation mechanism includes two fixed blocks, the bottom of the fixed blocks is connected to the top of the fixed base, a main shaft is connected in the fixed blocks, two first bevel gears are connected to the outside of the main shaft, the two first bevel gears are symmetrically distributed, and a second bevel gear is connected to the outside of each of the two rotating shafts, and the two first bevel gears are respectively connected to the second bevel gears.

[0007] Preferably, one side of one of the fixing blocks is connected to a motor, and the output end of the motor is connected to one end of the main shaft.

[0008] Preferably, the transfer mechanism includes a mounting shell, both ends of which are connected to the cleaning machine cabinet. A screw is connected inside the mounting shell, one end of which is connected to the side wall of the cleaning machine cabinet. A second motor is connected to one side of the cleaning machine cabinet, and the output end of the second motor is connected to one end of the screw.

[0009] Preferably, the screw is externally connected to a movable support platform, the top of the movable support platform is connected to two cylinders, the output end of the cylinders is connected to a support frame, and the bottom of the support frame is provided with two hooks.

[0010] Preferably, the hook frame is provided with a material rack, and the material rack is provided with a semiconductor silicon wafer.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. This application, through the cooperation of the rinsing head on the alkaline washing tank with the alkaline liquid pipe and the drain pipe, enables semiconductor silicon wafers to be directly rinsed in the alkaline tank after ultrasonic cleaning with acid and alkali solutions without having to be transferred to a water rinsing station for water rinsing. This solves the problem that traditional semiconductor silicon wafers need to be transferred to a water rinsing station after acid and alkali cleaning, resulting in a long overall cleaning time for semiconductor silicon wafers, and is conducive to improving the work efficiency of semiconductor silicon wafer cleaning. 2. This application uses an air knife tube to drive a nitrogen nozzle to adjust the working angle for drying the cleaned semiconductor silicon wafers. It also integrates the water rinsing and drying processes with the acid and alkali cleaning process in conjunction with a rinsing head. This solves the problem that traditional semiconductor silicon wafer cleaning requires acid and alkali cleaning, water rinsing, and drying, each of which requires additional arrangement, not only occupying too much space, but also increasing the risk of recontamination due to the frequent transfer of semiconductor silicon wafers. This is beneficial to improving the practical performance of semiconductor silicon wafer cleaning equipment. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall first-view structure of this utility model; Figure 2 This is a schematic diagram of the overall second-view structure of this utility model; Figure 3 This is a first-view structural schematic diagram of the alkaline washing tank of this utility model; Figure 4 This is a second-view structural schematic diagram of the alkaline washing tank of this utility model; Figure 5 This is a schematic diagram of the overall third-view structure of this utility model; Figure 6 This is a schematic diagram of the transfer mechanism structure of this utility model; Figure 7 This is an exploded structural diagram of the mounting shell and movable support platform of this utility model.

[0013] The diagram shows the following labels: 1. Cleaning machine cabinet; 2. Workbench; 3. Pickling tank; 4. Alkaline washing tank; 5. Alkaline washing liquid pipe; 6. Drain pipe; 7. Infusion pipe; 8. Drainage pipe; 9. Fixed base; 10. Flushing head; 11. Diverter pipe; 12. Conveying pipe; 13. Support plate; 14. Air knife pipe; 15. Nitrogen nozzle; 16. Nitrogen infusion pipe; 17. Rotating shaft; 18. Synchronous rotation mechanism; 19. Second bevel gear; 20. First bevel gear; 21. Main shaft; 22. Fixed block; 23. Motor 1; 24. Transfer mechanism; 25. Mounting shell; 26. Screw; 27. Motor 2; 28. Moving support platform; 29. ​​Cylinder; 30. Support frame; 31. Hook frame; 32. Material rack. Detailed Implementation

[0014] The embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of this utility model.

[0015] Please see Figures 1 to 7 A cleaning device for residual metal ions after semiconductor silicon wafer cutting includes a cleaning cabinet 1 and a workbench 2 installed in the cleaning cabinet 1. The cleaning cabinet 1 is equipped with a transfer mechanism 24. The workbench 2 is connected to an acid pickling tank 3 and an alkaline washing tank 4. When cleaning semiconductor silicon wafers, the silicon wafers are first immersed in the acid pickling tank 3, where the metal ions are dissolved by acidic chemical action, and ultrasonic waves enhance the dissolution efficiency. Then, the wafers are transferred to the alkaline washing tank 4, where organic matter is decomposed and particles are peeled off by alkaline chemical action, and ultrasonic waves further enhance the removal of impurities. It should be noted that both the pickling tank 3 and the alkaline washing tank 4 are equipped with ultrasonic devices. When the ultrasonic devices are working, their ultrasonic transducers will generate high-frequency vibrations, which will generate tiny bubbles in the acid and alkaline liquids. When the bubbles burst rapidly, they release local high pressure (up to thousands of atmospheres) and impact force, thereby cleaning the semiconductor silicon wafers immersed in the acid and alkaline cleaning solution. It is important to note that ultrasonic equipment is a well-known technology, and the installation of ultrasonic equipment in pickling tank 3 and alkaline washing tank 4 is also a conventional technology. It is a common method that can be understood and implemented by those skilled in the art based on common sense, so it will not be elaborated on further. The top of the alkaline washing tank 4 is connected to two fixed seats 9. Several rinsing heads 10 are connected inside the two fixed seats 9. One end of the several rinsing heads 10 is connected to a diversion pipe 11. One side of the diversion pipe 11 is connected to a conveying pipe 12. The conveying pipe 12 passes through the workbench 2 and is connected to an external water supply device. After the semiconductor silicon wafer is cleaned by the acid washing tank 3 and the alkaline washing tank 4, the alkaline washing liquid in the alkaline washing tank 4 is discharged to the temporary storage box at the bottom of the cleaning machine cabinet 1 by opening the drain pipe 6 of the alkaline washing liquid pipe 5. After the alkaline washing solution is discharged, the drain pipe 6 is closed and the drain pipe 8 is opened. At this time, the rinsing head 10 works to rinse the semiconductor silicon wafers in the alkaline washing tank 4 with water. The water sprayed out by the rinsing will be directly discharged through the drain pipe 8. After the semiconductor silicon wafers are rinsed with water and dried, the drain pipe 6 and drain pipe 8 are closed, and the infusion pipe 7 is opened to use a water pump to transport the alkaline cleaning solution in the temporary storage tank at the bottom of the cleaning cabinet 1 to the alkaline tank 4, so as to ensure the normal operation of the next batch of silicon wafer cleaning work. It should be added that the water used for rinsing is ultrapure water, which can avoid introducing any new contamination, ensure that the effect of the previous acid and alkali cleaning is not destroyed, and meet the stringent requirements of subsequent precision manufacturing processes for the cleanliness of the silicon wafer surface. More specifically, after acid washing and alkali washing, the silicon wafers have had metal ions, organic matter and particles removed through chemical action. At this time, the surface is in a "cleaning-up" state. If non-ultrapure water is used for rinsing, it is equivalent to re-attaching new contaminants (ions, particles, organic matter) to the silicon wafer, directly negating the effect of the previous acid washing and alkali washing, causing the previous cleaning work to be wasted. The high purity of ultrapure water can ensure that the rinsing process only removes residual contaminants without adding any new impurities, and finally allows the silicon wafer to enter the next process in a neutral and residue-free state. It is important to note that the external water supply equipment delivers ultrapure water through the delivery pipe 12 to the diversion pipe 11, and then delivers the ultrapure water to the rinsing head 10 for rinsing. Of course, the working principle of the external water supply equipment is a conventional technical means, and those skilled in the art can and should understand its specific functions and structure, so it will not be described in detail here. In this way, after the semiconductor silicon wafer is ultrasonically cleaned with acid and alkali solutions, it does not need to be transferred to the water rinsing area for water rinsing. It can be directly rinsed in the alkaline tank 4. This solves the problem that traditional semiconductor silicon wafers need to be transferred to the water rinsing area after being cleaned with acid and alkali solutions, which results in a long overall cleaning time for semiconductor silicon wafers. Two support plates 13 are connected to the top of each of the two fixed bases 9. An air knife tube 14 is provided in the two support plates 13. Several nitrogen nozzles 15 are connected to the outside of the air knife tube 14. A nitrogen delivery pipe 16 is connected to one side of the air knife tube 14. The nitrogen delivery pipe 16 is connected to an external nitrogen delivery device and delivers nitrogen. The nitrogen delivery pipe 16 delivers nitrogen to the air knife tube 14, so that the air knife tube 14 delivers nitrogen to each nitrogen nozzle 15. Nitrogen can form an inert protective layer on the surface of silicon wafers, which not only prevents external gases from reacting with the silicon wafers, but also prevents residual cleaning fluid from undergoing side reactions due to contact with air, thus fundamentally ensuring the stability of the chemical properties of the silicon wafer surface. Nitrogen nozzle 15 blows high-pressure nitrogen towards the silicon wafer, forcibly blowing away moisture through the impact force of the airflow. The drying time can be shortened to a few seconds, which is much faster than natural drying. Moreover, nitrogen is non-corrosive and will not cause physical scratches or stress damage to the surface of the silicon wafer even when sprayed at high speed, thus avoiding damage to the silicon wafer during the drying process. When drying silicon wafers, the transfer mechanism 24 needs to drive the material rack 32 and the silicon wafer to move up and down back and forth. When the silicon wafer is below the nitrogen nozzle 15, the air knife tube 14 drives the nitrogen nozzle 15 to rotate to tilt downwards, and then blows air to dry the silicon wafer. After a certain period of time, the silicon wafer is moved to the top of the nitrogen nozzle 15, and the air knife tube 14 drives the nitrogen nozzle 15 to rotate to tilt upwards, and then blows air to dry the silicon wafer. This process can be repeated to dry the silicon wafer thoroughly. This integrates the water rinsing and drying processes of semiconductor silicon wafers with the acid and alkali cleaning process, solving the problem that traditional semiconductor silicon wafer cleaning requires acid and alkali cleaning, water rinsing, and drying. Each process requires additional arrangement, which not only occupies too much space, but also increases the risk of recontamination due to the frequent transfer of semiconductor silicon wafers. The two ends of the air knife tube 14 are connected to the rotating shaft 17. The outside of the rotating shaft 17 is rotatably connected to the support plate 13. A synchronous rotating mechanism 18 is provided on one side of the two air knife tubes 14.

[0016] A number of alkaline washing liquid pipes 5 are connected to one side of the alkaline washing tank 4. The alkaline washing liquid pipes 5 include drain pipes 6 and delivery pipes 7. The drain pipes 6 and delivery pipes 7 are distributed at intervals. A number of drain pipes 8 are connected to one side of the alkaline washing tank 4.

[0017] The synchronous rotation mechanism 18 includes two fixed blocks 22. The bottom of the fixed blocks 22 is connected to the top of the fixed base 9. A main shaft 21 is connected in the fixed blocks 22. Two first bevel gears 20 are connected to the outside of the main shaft 21. The two first bevel gears 20 are symmetrically distributed. A second bevel gear 19 is connected to the outside of each of the two rotating shafts 17. The two first bevel gears 20 are connected to the second bevel gears 19 respectively. The output end of the motor 23 drives the main shaft 21 to rotate, so that the main shaft 21 drives the two first bevel gears 20 to rotate. At this time, the two first bevel gears 20 will drive the two second bevel gears 19 to rotate. Because the two first bevel gears 20 are symmetrically distributed, when the two first bevel gears 20 rotate synchronously, they will drive the two second bevel gears 19 to rotate synchronously in opposite directions. In this way, the two symmetrically distributed air knife tubes 14 will rotate synchronously in opposite directions, thereby achieving synchronous adjustment of the nitrogen nozzle 15 to face upwards and downwards.

[0018] One of the fixing blocks 22 is connected to a motor 23 on one side, and the output end of the motor 23 is connected to one end of the spindle 21.

[0019] The transfer mechanism 24 includes a mounting shell 25, with both ends of the mounting shell 25 connected to the cleaning machine cabinet 1. A screw 26 is connected inside the mounting shell 25, with one end of the screw 26 connected to the side wall of the cleaning machine cabinet 1. A motor 27 is connected to one side of the cleaning machine cabinet 1, with the output end of the motor 27 connected to one end of the screw 26. The output end of the motor 27 drives the screw 26 to rotate, causing the movable support platform 28 to move along the screw 26. In this way, the movable support platform 28 will drive the material rack 32 and silicon wafers to adjust their positions, so that the silicon wafers can move above the acid washing tank 3 and the alkaline washing tank 4. After being moved to the appropriate position, the output end of the cylinder 29 drives the support frame 30, hook frame 31, material rack 32 and silicon wafer to rise and fall, so that the material rack 32 can carry the silicon wafer into the acid washing tank 3 or the alkaline washing tank 4 for acid and alkaline cleaning.

[0020] The screw 26 is externally connected to a movable support 28. The top of the movable support 28 is connected to two cylinders 29. The output end of the cylinders 29 is connected to a support frame 30. The bottom of the support frame 30 is provided with two hook frames 31. The hook frames 31 cooperate with the material rack 32 to connect and install the material rack 32, thereby driving the material rack 32 and the silicon wafer to move.

[0021] A material rack 32 is set on the hook frame 31, and semiconductor silicon wafers are set in the material rack 32. Only one silicon wafer is displayed, not all of them, so as not to affect the integrity of the technical solution.

[0022] When using this utility model: First, when cleaning semiconductor silicon wafers, the wafers are first immersed in acid washing tank 3, where metal ions are dissolved through acidic chemical action, and ultrasonic waves enhance the dissolution efficiency; then they are transferred to alkaline washing tank 4, where organic matter is decomposed and particles are peeled off through alkaline chemical action, and ultrasonic waves further enhance the removal of impurities. Secondly, after the semiconductor silicon wafers have been cleaned by the acid washing tank 3 and the alkaline washing tank 4, the drain pipe 6 of the alkaline washing liquid pipe 5 is opened, allowing the alkaline washing liquid in the alkaline washing tank 4 to be discharged into the temporary storage tank at the bottom of the cleaning machine cabinet 1. After the alkaline washing liquid is discharged, the drain pipe 6 is closed and the drain pipe 8 is opened. At this time, the rinsing head 10 works to rinse the semiconductor silicon wafers in the alkaline washing tank 4 with water. The water sprayed out by the rinsing will be directly discharged through the drain pipe 8. After the semiconductor silicon wafers are rinsed with water and the subsequent drying work is completed, the drain pipe 6 and the drain pipe 8 are closed, and the infusion pipe 7 is opened to use a water pump to transport the alkaline cleaning liquid in the temporary storage tank at the bottom of the cleaning machine cabinet 1 to the alkaline tank 4, ensuring the normal operation of the next batch of silicon wafer cleaning work. Then, the nitrogen pipeline 16 is connected to an external nitrogen delivery device to deliver nitrogen. The nitrogen pipeline 16 delivers nitrogen to the air knife tube 14, which in turn delivers nitrogen to each nitrogen nozzle 15. The nitrogen nozzle 15 blows high-pressure nitrogen onto the silicon wafer, forcibly blowing away moisture through the airflow impact force. The drying time can be shortened to a few seconds, which is much faster than natural drying. Furthermore, nitrogen is non-corrosive and will not cause physical scratches or stress damage to the silicon wafer surface even with high-speed spraying, thus avoiding silicon wafer breakage during the drying process. Finally, when drying the silicon wafer, the transfer mechanism 24 needs to drive the material rack 32 and the silicon wafer to move up and down back and forth. When the silicon wafer is below the nitrogen nozzle 15, the air knife tube 14 drives the nitrogen nozzle 15 to rotate to tilt downwards, and then blows air to dry the silicon wafer. After a certain period of time, the silicon wafer is moved to above the nitrogen nozzle 15, and the air knife tube 14 drives the nitrogen nozzle 15 to rotate to tilt upwards, and then blows air to dry the silicon wafer. This process can be repeated to dry the silicon wafer thoroughly.

[0023] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, all of which fall within the protection scope of the present invention, which is defined by the appended claims and their equivalents.

Claims

1. A cleaning device for residual metal ions after semiconductor silicon wafer dicing, comprising a cleaning cabinet (1) and a workbench (2) installed in the cleaning cabinet (1), characterized in that: The cleaning machine cabinet (1) is equipped with a transfer mechanism (24), and the workbench (2) is connected to an acid washing tank (3) and an alkaline washing tank (4). The top of the alkaline washing tank (4) is connected to two fixed seats (9), and the interior of each of the two fixed seats (9) is connected to several flushing heads (10). One end of each of the several flushing heads (10) is connected to a diversion pipe (11), and one side of the diversion pipe (11) is connected to a conveying pipe (12). The conveying pipe (12) passes through the workbench (2) and is connected to an external water supply device. Two support plates (13) are connected to the top of each of the two fixed bases (9). Air knife tubes (14) are provided in the two support plates (13). Several nitrogen nozzles (15) are connected to the outside of the air knife tubes (14). A nitrogen delivery pipe (16) is connected to one side of the air knife tubes (14). Rotating shafts (17) are connected to both ends of the air knife tubes (14). The outside of the rotating shafts (17) is rotatably connected to the support plates (13). A synchronous rotation mechanism (18) is provided on one side of the two air knife tubes (14).

2. The cleaning device for residual metal ions after semiconductor silicon wafer dicing according to claim 1, characterized in that: The alkaline washing tank (4) is connected to a number of alkaline washing liquid pipes (5) on one side. The number of alkaline washing liquid pipes (5) includes a drain pipe (6) and a delivery pipe (7). The number of drain pipes (6) and delivery pipes (7) are distributed at intervals. The alkaline washing tank (4) is connected to a number of drain pipes (8) on one side.

3. The cleaning device for residual metal ions after semiconductor silicon wafer dicing according to claim 1, characterized in that: The synchronous rotation mechanism (18) includes two fixed blocks (22), the bottom of which is connected to the top of the fixed seat (9). A main shaft (21) is connected in the fixed block (22), and two first bevel gears (20) are connected to the outside of the main shaft (21). The two first bevel gears (20) are symmetrically distributed. A second bevel gear (19) is connected to the outside of each of the two rotating shafts (17), and the two first bevel gears (20) are respectively connected to the second bevel gears (19).

4. The cleaning device for residual metal ions after semiconductor silicon wafer dicing according to claim 3, characterized in that: One of the fixed blocks (22) is connected to a motor (23) on one side, and the output end of the motor (23) is connected to one end of the main shaft (21).

5. The cleaning device for residual metal ions after semiconductor silicon wafer dicing according to claim 1, characterized in that: The transfer mechanism (24) includes a mounting shell (25), both ends of which are connected to the cleaning machine cabinet (1). A screw (26) is connected inside the mounting shell (25), one end of which is connected to the side wall of the cleaning machine cabinet (1). A motor (27) is connected to one side of the cleaning machine cabinet (1), and the output end of the motor (27) is connected to one end of the screw (26).

6. The cleaning device for residual metal ions after semiconductor silicon wafer dicing according to claim 5, characterized in that: The screw (26) is externally connected to a movable support (28), the top of the movable support (28) is connected to two cylinders (29), the output end of the cylinders (29) is connected to a support frame (30), and the bottom of the support frame (30) is provided with two hooks (31).

7. The cleaning apparatus for residual metal ions after semiconductor silicon wafer dicing according to claim 6, characterized in that: A material rack (32) is provided on the hook frame (31), and a semiconductor silicon wafer is provided in the material rack (32).

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