Device for cutting silicon wafer underwater by using green wavelength laser
The underwater silicon wafer cutting device using green wavelength lasers solves the damage and contamination problems caused by traditional mechanical cutting, achieving high-precision, low-damage cutting results and meeting the high-quality cutting needs of the semiconductor industry.
Patent Information
- Application Number
- CN202422569826.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-23
- Publication Date
- 2025-11-04
- Estimated Expiration
- 2034-10-23
AI Technical Summary
Traditional silicon wafer dicing technology uses diamond blades for mechanical cutting, which may damage the silicon wafer and generate dust and debris that pollute the environment, making it difficult to meet the semiconductor industry's demand for high-precision, low-damage dicing.
The device uses a green wavelength laser to cut silicon wafers underwater. The laser head is focused on the surface of the silicon wafer through a high-transmittance glass and liquid. By adjusting the liquid flow rate and laser parameters, non-contact cutting is achieved. Debris is removed by liquid flushing and filtering to ensure cutting quality.
It achieves high-precision, low-damage silicon wafer cutting, reduces physical stress, improves cutting quality and efficiency, and meets the process requirements of the semiconductor industry.
Smart Images
Figure CN223506422U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of silicon wafer cutting technology, and in particular to a device for underwater cutting of silicon wafers using a green wavelength laser. Background Technology
[0002] A silicon wafer is a silicon chip used in the fabrication of silicon semiconductor integrated circuits. Because of its circular shape, it is called a silicon wafer. Various circuit element structures can be fabricated on silicon wafers to create integrated circuit products with specific electrical functions. Traditional silicon wafer dicing technology typically uses diamond blades for mechanical cutting. This method requires applying physical pressure to the silicon wafer, which may damage it. Furthermore, the dust and debris generated during mechanical cutting can easily pollute the surrounding environment. Therefore, improvements are needed. Utility Model Content
[0003] Therefore, it is necessary to provide a device for underwater cutting of silicon wafers using a green wavelength laser, which addresses the problem that traditional silicon wafer cutting technology typically uses diamond blades for mechanical cutting. This method requires applying physical pressure to the silicon wafer, which may damage it. In addition, the dust and debris generated during mechanical cutting can easily pollute the surrounding environment.
[0004] This utility model provides a device for underwater cutting of silicon wafers using a green wavelength laser, comprising:
[0005] The workbench has a first support and a second support, the second support has a first cylinder, and the output end of the first cylinder has a third support.
[0006] A container, fixed to a first support member, and having a container lid, the container lid having a high-transmittance glass in the middle;
[0007] A wafer chuck is mounted on the inner wall of the container;
[0008] A water pump is installed on the first support and has an inlet pipe and an outlet pipe. The inlet end of the inlet pipe is located on one side of the container, and the outlet end of the outlet pipe is located on the other side of the container.
[0009] A filter is installed on the inlet pipe;
[0010] A laser cutter, mounted on the third support, has a laser head.
[0011] In one embodiment, the container lid includes a bent portion and a recessed portion, the high-transmittance glass is located in the recessed portion, and the angle of the bent portion is a right angle.
[0012] In one embodiment, a fourth support member is fixedly connected to the inner wall of the container, the fourth support member dividing the inner cavity of the container into a gas cavity and a liquid cavity. A second cylinder is installed in the gas cavity, and a limiting cylinder is fixedly connected to the output end of the second cylinder. The limiting cylinder is located in the liquid cavity, and the wafer chuck is installed on the inner bottom wall of the limiting cylinder.
[0013] In one embodiment, an X-axis adjustment assembly is mounted on the surface of the worktable, and a Y-axis adjustment assembly is mounted on the surface of the X-axis adjustment assembly. Both the X-axis and Y-axis adjustment assemblies include a fifth support member. A motor is mounted on the surface of the fifth support member, and a lead screw is fixedly connected to the output end of the motor. A guide rail is fixedly connected to the surface of the fifth support member, and a slider is slidably connected to the guide rail. The slider is threadedly connected to the lead screw. The fifth support member in the X-axis adjustment assembly is fixed to the worktable, and the fifth support member in the Y-axis adjustment assembly is fixed to the slider in the X-axis adjustment assembly. The first support member is fixed to the slider in the Y-axis adjustment assembly.
[0014] In one embodiment, the laser beam emitted by the laser head has a wavelength of 532nm, the cutting power of the laser head is 10W-40W, and the laser speed of the laser head is 600mm / s-2000mm / s.
[0015] In one embodiment, the optical path distance of the laser cutter during underwater laser cutting is in the range of 0.1-10 mm.
[0016] In one embodiment, the liquid in the container includes deionized water, aqueous solution, or other liquids that facilitate underwater silicon wafer dicing.
[0017] In one embodiment, the flow rate of the liquid in the container is in the range of 1-20 L / min.
[0018] The aforementioned device for underwater silicon wafer cutting using a green wavelength laser fixes the silicon wafer on a wafer chuck, fills a container with liquid, and closes the container lid. The 532nm laser beam passes through the high-transparency glass at the bottom of the container lid and the liquid above the silicon wafer, focusing onto the surface of the wafer. By adjusting the distance between the wafer and the high-transparency glass, the flow rate of the liquid, and the laser parameters, high-quality silicon wafer cutting is achieved. During the cutting process, a water pump is activated to maintain a stable flow rate of the liquid in the container. On the one hand, the liquid flushes away the debris generated during the cutting process, and the molten area is quickly solidified to prevent adhesion to the debris. At the same time, it facilitates the flushing away of a large number of air bubbles generated when the laser interacts with the liquid. These air bubbles can cause severe laser scattering. The filter effectively filters out debris and other impurities in the discharged liquid, ensuring the recycling of the liquid during cutting and improving the cutting quality. On the other hand, by adopting a non-contact processing method, the physical pressure on the wafer is reduced, which can meet the semiconductor industry's demand for high-precision, low-damage cutting processes. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0020] Figure 1 This is a schematic diagram of the device structure for underwater cutting of silicon wafers using a green wavelength laser in one embodiment;
[0021] Figure 2 This is a partial structural diagram of a device for underwater cutting of silicon wafers using a green wavelength laser, as shown in one embodiment.
[0022] Figure 3 This is a schematic cross-sectional view of the container in one embodiment;
[0023] Figure 4 This is a schematic diagram of the Y-axis adjustment component structure in one embodiment.
[0024] Figure label:
[0025] 200. Workbench; 210. First support component; 220. Second support component; 230. First cylinder; 240. Third support component; 300. Container; 310. Container lid; 311. Bending part; 312. Recessed part; 320. High-transmittance glass; 330. Fourth support component; 340. Second cylinder; 350. Limiting cylinder; 360. Gas chamber; 370. Liquid chamber; 400. Wafer chuck; 500. Water pump; 510. Liquid inlet pipe; 520. Liquid outlet pipe; 600. Filter; 700. Laser cutter; 710. Laser head; 800. X-axis adjustment assembly; 810. Y-axis adjustment assembly; 811. Fifth support component; 812. Motor; 813. Lead screw; 814. Guide rail; 815. Slider. Detailed Implementation
[0026] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0027] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this specification are for illustrative purposes only and do not represent the only possible implementation.
[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0029] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0030] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this specification belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.
[0031] The following is combined Figures 1-4 This invention describes an apparatus for underwater cutting of silicon wafers using a green wavelength laser.
[0032] like Figure 1 , Figure 2 and Figure 3 As shown, in one embodiment, an apparatus for underwater cutting of silicon wafers using a green wavelength laser includes a worktable 200, a container 300, a wafer chuck 400, a water pump 500, a filter 600, and a laser cutter 700.
[0033] The workbench 200 has a first support member 210 and a second support member 220. The second support member 220 has a first cylinder 230, and the output end of the first cylinder 230 has a third support member 240.
[0034] The container 300 is fixed to the first support member 210, and the container 300 has a container lid 310, with a high-transmittance glass 320 in the middle of the container lid 310.
[0035] It should be noted that the liquid in container 300 includes deionized water, aqueous solution, and other liquids that are beneficial for underwater silicon wafer dicing. The flow rate of the liquid in container 300 is in the range of 1-20 L / min.
[0036] The wafer chuck 400 is mounted on the inner wall of the container 300.
[0037] The water pump 500 is mounted on the first support member 210, and the water pump 500 has an inlet pipe 510 and an outlet pipe 520. The inlet end of the inlet pipe 510 is located on one side of the container 300, and the outlet end of the outlet pipe 520 is located on the other side of the container 300.
[0038] It should be noted that the flow rate of the water pump 500 can be precisely adjusted, the water outlet of the liquid outlet pipe 520 is higher than the high-transparency glass 320, and the water inlet of the liquid inlet pipe 510 is lower than the processing plane of the silicon wafer. This allows the water flow to more effectively carry away the debris generated during laser cutting. Furthermore, no matter how fast the water flow is, the water surface above the silicon wafer will not fluctuate because it is in contact with the glass, thus ensuring the stability during laser cutting.
[0039] The filter 600 is installed on the inlet pipe 510.
[0040] It should be noted that the filter 600 consists of a housing, multiple filter elements, a backwashing mechanism, and a differential pressure controller. A transverse partition inside the housing divides its internal cavity into upper and lower chambers. The upper chamber houses multiple filter elements, thus expanding the filtration space and significantly reducing the overall volume of the filter 600. A backwashing suction cup is installed in the lower chamber. During operation, turbid liquid enters the lower chamber of the filter 600 through the inlet and then flows through the partition holes into the inner cavity of the filter elements. Impurities larger than the filter element gaps are trapped, while the clean liquid passes through the gaps to reach the upper chamber and is finally discharged from the outlet. The filter 600 uses a high-strength wedge-shaped filter screen and automatically cleans the filter elements through differential pressure control and timer control. When impurities accumulate on the surface of the filter elements, causing the inlet and outlet pressure difference to increase to a set value, or when the timer reaches the preset time, the electric control box sends a signal to drive the backwashing mechanism. When the backwash suction nozzle is aligned with the filter element inlet, the drain valve opens, and the system depressurizes and drains water. A negative pressure zone appears between the suction nozzle and the inner side of the filter element, where the relative pressure is lower than the water pressure on the outer side of the filter element. This forces some of the clean circulating water to flow from the outer side of the filter element into the inner side. Impurities adsorbed on the inner wall of the filter element are carried into the suction nozzle with the water flow and discharged from the drain valve. The pressure difference between the inlet and outlet of the filter 600 returns to normal or the timer setting time ends.
[0041] A laser cutter 700 is mounted on a third support 240 and has a laser head 710.
[0042] It should be further explained that the height of the laser head 710 can be adjusted by controlling the first cylinder 230. The laser beam emitted by the laser head 710 has a wavelength of 532nm, a cutting power of 10W-40W, and a laser speed of 600mm / s-2000mm / s. The optical path distance of the laser cutter 700 in underwater laser cutting is within the range of 0.1-10mm. By adjusting appropriate laser process parameters such as laser power, scanning speed, and focal position, as well as liquid parameters such as liquid flow rate, underwater optical path, and liquid composition, the quality and efficiency of underwater laser cutting can be further improved, resulting in silicon wafers that meet the requirements for use.
[0043] The device for underwater silicon wafer cutting using a green wavelength laser works by fixing the silicon wafer to a wafer chuck 400, filling a container 300 with liquid, and then covering it with a lid 310. A 532nm laser beam passes through a high-transparency glass 320 at the bottom of the lid 310 and the liquid above the silicon wafer, focusing onto the surface of the wafer. By adjusting the distance between the wafer and the high-transparency glass 320, the liquid flow rate, and the laser parameters, high-quality silicon wafer cutting is achieved. During the cutting process, a water pump 500 maintains a stable liquid flow rate within the container 300. On the one hand, the liquid flushes away the debris generated during the cutting process, and the molten area solidifies quickly to prevent it from sticking to the debris. At the same time, it facilitates the removal of a large number of air bubbles generated when the laser interacts with the liquid. These air bubbles can easily cause severe laser scattering. The filter 600 effectively filters out debris and other impurities in the discharged liquid, ensuring the recycling of the liquid during cutting and improving the cutting quality. On the other hand, by adopting a non-contact processing method, the physical pressure on the wafer is reduced, which can meet the semiconductor industry's demand for high-precision, low-damage cutting processes.
[0044] In this embodiment, the container lid 310 includes a bent portion 311 and a recessed portion 312, with the high-transmittance glass 320 located in the recessed portion 312, and the angle of the bent portion 311 being a right angle.
[0045] The special design of the container lid 310 prevents water surface ripples above the silicon wafer, thus avoiding interference with the laser cutting beam.
[0046] In this embodiment, a fourth support member 330 is fixedly connected to the inner wall of the container 300. The fourth support member 330 divides the inner cavity of the container 300 into a gas cavity 360 and a liquid cavity 370. A second cylinder 340 is installed in the gas cavity 360. The output end of the second cylinder 340 is fixedly connected to a limiting cylinder 350. The limiting cylinder 350 is located in the liquid cavity 370. The wafer chuck 400 is installed on the inner bottom wall of the limiting cylinder 350.
[0047] The height of the silicon wafer in the liquid can be easily adjusted as needed by controlling the second cylinder 340, while the limiting cylinder 350 can effectively prevent the silicon wafer from shifting under the impact of the fluid during the cutting process, thereby improving the cutting accuracy.
[0048] In this embodiment, see Figure 4 An X-axis adjustment assembly 800 is mounted on the surface of the worktable 200, and a Y-axis adjustment assembly 810 is mounted on the surface of the X-axis adjustment assembly 800. Both the X-axis adjustment assembly 800 and the Y-axis adjustment assembly 810 include a fifth support member 811. A motor 812 is mounted on the surface of the fifth support member 811, and a lead screw 813 is fixedly connected to the output end of the motor 812. A guide rail 814 is fixedly connected to the surface of the fifth support member 811, and a slider 815 is slidably connected to the guide rail 814. The slider 815 is threadedly connected to the lead screw 813. The fifth support member 811 in the X-axis adjustment assembly 800 is fixed on the worktable 200, and the fifth support member 811 in the Y-axis adjustment assembly 810 is fixed on the slider 815 in the X-axis adjustment assembly 800. The first support member 210 is fixed on the slider 815 in the Y-axis adjustment assembly 810.
[0049] When in use, the X-axis adjustment assembly 800 or the Y-axis adjustment assembly 810 is driven by the start motor 812 to move the lead screw 813. The lead screw 813 drives the slider 815 to move on the guide rail 814, thereby facilitating the adjustment of the position of the silicon wafer in the XY plane.
[0050] This device for underwater cutting of silicon wafers using a green wavelength laser has several advantages. First, the cooling effect of the liquid environment significantly reduces the heat-affected zone, protecting the material's physical properties and preventing deformation or damage. Second, underwater cutting provides smoother and more precise cutting edges, reducing the need for subsequent processing. Due to its high cutting precision, underwater cutting reduces material waste and improves material utilization. Third, the flow of the liquid helps capture and remove dust and debris, greatly improving cutting efficiency. Furthermore, the flow of the liquid effectively solves the problem of air bubbles interfering with the laser when it interacts with the liquid.
[0051] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0052] The above-described embodiments are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the appended claims.
Claims
1. A device for underwater cutting of silicon wafers using a green wavelength laser, characterized in that, include: The workbench has a first support and a second support, the second support has a first cylinder, and the output end of the first cylinder has a third support. A container, fixed to a first support member, and having a container lid, the container lid having a high-transmittance glass in the middle; A wafer chuck is mounted on the inner wall of the container; A water pump is installed on the first support and has an inlet pipe and an outlet pipe. The inlet end of the inlet pipe is located on one side of the container, and the outlet end of the outlet pipe is located on the other side of the container. A filter is installed on the inlet pipe; A laser cutter, mounted on the third support, has a laser head.
2. The apparatus for underwater cutting of silicon wafers using a green wavelength laser according to claim 1, characterized in that, The container lid includes a bent portion and a concave portion, the high-transmittance glass is located in the concave portion, and the angle of the bent portion is a right angle.
3. The apparatus for underwater cutting of silicon wafers using a green wavelength laser according to claim 2, characterized in that, The inner wall of the container is fixedly connected to a fourth support member, which divides the inner cavity of the container into a gas cavity and a liquid cavity. A second cylinder is installed in the gas cavity, and a limiting cylinder is fixedly connected to the output end of the second cylinder. The limiting cylinder is located in the liquid cavity, and the wafer chuck is installed on the inner bottom wall of the limiting cylinder.
4. The apparatus for underwater cutting of silicon wafers using a green wavelength laser according to claim 1, characterized in that, An X-axis adjustment assembly is mounted on the surface of the worktable, and a Y-axis adjustment assembly is mounted on the surface of the X-axis adjustment assembly. Both the X-axis and Y-axis adjustment assemblies include a fifth support member. A motor is mounted on the surface of the fifth support member, and a lead screw is fixedly connected to the output end of the motor. A guide rail is fixedly connected to the surface of the fifth support member, and a slider is slidably connected to the guide rail. The slider is threadedly connected to the lead screw. The fifth support member in the X-axis adjustment assembly is fixed to the worktable, and the fifth support member in the Y-axis adjustment assembly is fixed to the slider in the X-axis adjustment assembly. The first support member is fixed to the slider in the Y-axis adjustment assembly.
5. The apparatus for underwater cutting of silicon wafers using a green wavelength laser according to claim 4, characterized in that, The laser head emits a laser beam with a wavelength of 532nm, the laser head has a cutting power of 10W-40W, and the laser speed of the laser head is 600mm / s-2000mm / s.
6. The apparatus for underwater cutting of silicon wafers using a green wavelength laser according to claim 5, characterized in that, The laser cutter has an optical path distance of 0.1-10 mm for underwater laser cutting.
7. The apparatus for underwater cutting of silicon wafers using a green wavelength laser according to claim 6, characterized in that, The flow rate of the liquid in the container is in the range of 1-20 L / min.