Silicon wafer surface metal ion collection device and method

Abstract

The application provides a silicon wafer surface metal ion collecting device and method, and belongs to the technical field of semiconductor manufacturing. The silicon wafer surface metal ion collecting device comprises: at least one set of mechanical arms, each set of mechanical arms comprising a pair of mirror-imaged carriages for fixing silicon wafers; a scanning assembly comprising a main body structure and a pair of mirror-imaged scanning heads arranged at one end of the main body structure, the scanning heads corresponding to the carriages one by one, and a scanning pipeline arranged inside the main body structure for transmitting scanning liquid, the scanning pipeline being in communication with liquid outlets of the two scanning heads; and a scanning liquid storage structure for delivering scanning liquid to the liquid outlets through pressure action via the scanning pipeline or recovering the scanning liquid from the liquid outlets via the scanning pipeline through suction action. The application can improve the scanning efficiency of silicon wafers.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a device and method for collecting metal ions on the surface of a silicon wafer. Background Technology

[0002] Silicon wafers are produced by using the Magnetic Field Czochralski Method (MCZ) to obtain single-crystal silicon rods, which are then processed through wire cutting, grinding, polishing, and cleaning. During silicon wafer processing, various metallic impurities can contaminate the wafers, leading to device failure. Light metals (Na, Mg, Al, K, Ca, etc.) can cause device breakdown and voltage reduction, while heavy metals (Cr, Mn, Fe, Ni, Cu, Zn, etc.) can reduce device lifespan. As the raw material for devices, the surface metal content of silicon wafers directly affects the device yield. Therefore, it is necessary to test and control the metal ion content on the silicon wafer surface to below certain specifications to meet the requirements of subsequent processes.

[0003] In related technologies, multiple silicon wafers are scanned sequentially to collect metal ions, which is time-consuming and has low efficiency. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a device and method for collecting metal ions on the surface of silicon wafers, which can improve the efficiency of scanning silicon wafers.

[0005] To achieve the above objectives, the technical solution adopted in the embodiments of the present invention is as follows:

[0006] A device for collecting metal ions on a silicon wafer surface, comprising:

[0007] At least one set of robotic arms, each set of robotic arms including a pair of mirror-arranged stages for fixing silicon wafers;

[0008] The scanning assembly includes a main structure and a pair of scanning heads arranged in a mirror image at one end of the main structure. Each scanning head corresponds to a stage. The main structure is provided with a scanning pipeline for transmitting scanning fluid, and the scanning pipeline is connected to the outlet of the two scanning heads.

[0009] The scanning fluid storage structure is used to deliver the scanning fluid through the scanning tubing to the outlet by pressure, or to recover the scanning fluid from the outlet through the scanning tubing by suction.

[0010] In some embodiments, the scanning head includes two hinges disposed at the liquid outlet. When the scanning liquid storage structure delivers the scanning liquid to the liquid outlet through the scanning tube under pressure, the two hinges open under pressure, and the scanning liquid flows out from the scanning tube to the liquid outlet. When the scanning liquid storage structure recovers the scanning liquid from the liquid outlet through the scanning tube using suction, the two hinges close under suction, sealing the liquid outlet.

[0011] In some embodiments, the scanning head is further provided with a ring of air holes surrounding the two hinges and a gas supply component for introducing gas into the air holes. The air outlet direction of the air holes is towards the center of the liquid outlet. When the scanning liquid flows out from the scanning tube to the liquid outlet, the gas supply component introduces gas into the air holes, causing the scanning liquid to gather at the center of the liquid outlet under the action of the airflow.

[0012] In some embodiments, the stage is capable of rotating about its own central axis.

[0013] In some embodiments, the stage is provided with vacuum holes for adsorbing silicon wafers.

[0014] This invention also provides a method for collecting metal ions from a silicon wafer surface, applied to the silicon wafer surface metal ion collection device described above, the method comprising:

[0015] The two silicon wafers to be scanned are fixed in place by the stage, so that the two silicon wafers are arranged in a mirror image.

[0016] Adjust the spacing between the two silicon wafers, control the pair of scanning heads to be positioned between the two silicon wafers, and use pressure to deliver the scanning liquid through the scanning pipeline to the outlet. The scanning liquid from the outlet of each scanning head contacts the surface of a silicon wafer.

[0017] The silicon wafer is scanned using the scanning head. After the scan is completed, the scanning liquid is recovered from the outlet through the scanning pipeline by suction.

[0018] In some embodiments, the method includes:

[0019] When the scanning fluid is delivered to the outlet through the scanning tube by pressure, the two hinges open due to the pressure, and the scanning fluid flows out from the scanning tube to the outlet. When the scanning fluid is recovered from the outlet through the scanning tube by suction, the two hinges close due to the suction, thus sealing the outlet.

[0020] In some embodiments, the method further includes:

[0021] When the scanning fluid flows out of the scanning tube to the outlet, gas is introduced into the gas vent through the gas supply component, so that the scanning fluid gathers at the center of the outlet under the action of the airflow.

[0022] In some embodiments, scanning the silicon wafer using the scanning head includes:

[0023] The stage is controlled to rotate the silicon wafer, and the robotic arm is controlled to move horizontally, so that the scanning component can scan the two silicon wafers simultaneously.

[0024] In some embodiments, scanning the silicon wafer using the scanning head includes:

[0025] The stage is controlled to rotate the silicon wafer, and the scanning component is controlled to move horizontally, so that the scanning component can scan the two silicon wafers at the same time.

[0026] The beneficial effects of this invention are:

[0027] In this embodiment, the robotic arm can simultaneously fix two silicon wafers using a pair of mirrored platforms. The scanning component includes dual scanning heads, each corresponding to a platform, enabling simultaneous scanning of both silicon wafers. This improves the efficiency of silicon wafer scanning, ensuring the accuracy of ultra-trace metal testing on silicon wafers while effectively increasing testing efficiency, significantly reducing testing time, and accelerating production cycle. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the silicon wafer surface metal ion collection device according to an embodiment of the present invention;

[0029] Figure 2 This is a schematic diagram of the structure of the platform according to an embodiment of the present invention;

[0030] Figure 3 A schematic diagram showing the structure of the scanning component and the scanning fluid storage structure according to an embodiment of the present invention;

[0031] Figure 4 A schematic diagram illustrating the hinge closure according to an embodiment of the present invention;

[0032] Figure 5 This is a schematic diagram showing the hinge of an embodiment of the present invention open.

[0033] Figure Labels

[0034] 1. Robotic arm

[0035] 2 Scanning Components

[0036] 3 platforms

[0037] 4 Vacuum Holes

[0038] 5 pores

[0039] 6 hinges

[0040] 7 Scanning Head

[0041] 8 silicon wafers

[0042] 9. Scanning tubing

[0043] 10 Scanning Fluid Storage Structure Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0045] This invention provides a device and method for collecting metal ions on the surface of silicon wafers, which can improve the efficiency of scanning silicon wafers.

[0046] This invention provides a device for collecting metal ions on a silicon wafer surface, such as... Figures 1-3 As shown, it includes:

[0047] At least one set of robotic arms 1, each set of robotic arms 1 including a pair of mirror-arranged stages 3, said stages 3 being used to fix silicon wafers 8;

[0048] The scanning component 2 includes a main structure and a pair of scanning heads 7 arranged in a mirror image at one end of the main structure. The scanning heads 7 correspond one-to-one with the stage 3. The main structure is provided with a scanning pipeline for transmitting scanning fluid. The scanning pipeline is connected to the liquid outlet of the two scanning heads 7.

[0049] The scanning fluid storage structure 10 is used to deliver the scanning fluid through the scanning tubing to the outlet by pressure, or to recover the scanning fluid from the outlet through the scanning tubing by suction.

[0050] In this embodiment, the robotic arm 1 can simultaneously fix two silicon wafers 8 through a pair of mirror-set platforms 3. The scanning component 2 includes dual scanning heads 7, which correspond one-to-one with the platforms 3, enabling simultaneous scanning of the two silicon wafers 8. This improves the efficiency of scanning the silicon wafers 8, effectively increasing testing efficiency while ensuring the accuracy of ultra-trace metal testing on the silicon wafers 8, greatly reducing testing time, and accelerating the production cycle.

[0051] In this embodiment, the silicon wafer surface metal ion collection device may include a group of robotic arms 1, or n (n greater than 1) groups of robotic arms 1. When the silicon wafer surface metal ion collection device includes n groups of robotic arms 1, it can scan 2n silicon wafers 8 simultaneously, thereby improving the efficiency of scanning the silicon wafers 8.

[0052] In this embodiment, the platform 3 can rotate around its own central axis, and the robotic arm 1 can flip and rise / fall. Figure 2 As shown, the stage 3 is provided with vacuum holes 4 for adsorbing silicon wafers 8, and the stage 3 can fix the silicon wafers 8 by vacuum adsorption.

[0053] In some embodiments, such as Figure 4 and Figure 5 As shown, the scanning head 7 includes two hinges 6 disposed at the liquid outlet. When the scanning liquid storage structure 10 delivers the scanning liquid to the liquid outlet through the scanning pipeline under pressure, the two hinges 6 open under pressure, and the scanning liquid flows out from the scanning pipeline to the liquid outlet. When the scanning liquid storage structure 10 recovers the scanning liquid from the liquid outlet through the scanning pipeline under suction, the two hinges 6 close under suction, sealing the liquid outlet.

[0054] In some embodiments, such as Figure 5 As shown, the scanning head 7 is also provided with a ring of air holes 5 surrounding the two hinges 6 and a gas supply component for introducing gas into the air holes 5. The air outlet direction of the air holes 5 is towards the center of the liquid outlet. When the scanning liquid flows out from the scanning tube to the liquid outlet, the gas supply component introduces gas into the air holes 5 so that the scanning liquid gathers at the center of the liquid outlet under the action of the airflow.

[0055] In this embodiment, the end of the scanning pipeline splits into two opposing paths, each leading to a separate scanning head 7. Two hinges 6 are installed at the outlet of the scanning head 7; these hinges are closed when no external force is applied. During scanning, the scanning fluid storage structure 10 delivers the scanning fluid through the scanning pipeline to the outlet under pressure. The two hinges 6 open under pressure, and the scanning fluid flows out. Simultaneously, the gas supply component introduces gas into the vent 5, blowing the gas towards the center of the outlet. Under the influence of the airflow, the scanning fluid accumulates at the opening of the hinges 6 and remains accumulated during the scanning process. After scanning, the scanning fluid storage structure 10 uses suction to recover the scanning fluid from the outlet through the scanning pipeline, and the two hinges 6 close. This embodiment, by providing hinges 6 and vents 5 on the scanning head 7, enables simultaneous scanning of multiple silicon wafers 8 and solves the problem of scanning fluid recovery during anti-gravity reverse scanning.

[0056] This invention also provides a method for collecting metal ions from a silicon wafer surface, applied to the silicon wafer surface metal ion collection device described above, the method comprising:

[0057] The stage 3 is used to fix the two silicon wafers 8 to be scanned, so that the two silicon wafers 8 are arranged in a mirror image.

[0058] Adjust the spacing between the two silicon wafers 8, control the pair of scanning heads 7 to be positioned between the two silicon wafers 8, and deliver the scanning liquid to the outlet through the scanning pipeline by pressure. The scanning liquid at the outlet of each scanning head 7 contacts the surface of one silicon wafer 8 respectively.

[0059] The silicon wafer 8 is scanned using the scanning head 7. After the scan is completed, the scanning liquid is recovered from the outlet through the scanning pipeline by suction.

[0060] In this embodiment, two silicon wafers 8 can be scanned simultaneously, which improves the efficiency of scanning the silicon wafers 8. While ensuring the accuracy of ultra-trace metal testing on the silicon wafers 8, it can effectively improve testing efficiency, greatly reduce testing time, and speed up production cycle.

[0061] In some embodiments, the method includes:

[0062] When the scanning fluid is delivered to the outlet through the scanning tube by pressure, the two hinges 6 open due to the pressure, and the scanning fluid flows out from the scanning tube to the outlet. When the scanning fluid is recovered from the outlet through the scanning tube by suction, the two hinges 6 close due to the suction, thus sealing the outlet.

[0063] In some embodiments, the method further includes:

[0064] When the scanning liquid flows out of the scanning tube to the outlet, gas is introduced into the gas port 5 through the gas supply component, so that the scanning liquid gathers at the center of the outlet under the action of the airflow.

[0065] Specifically, when scanning of silicon wafers 8 is required, the robotic arm 1 in the same group uses the stage 3 on the robotic arm 1 to vacuum-adsorb the two silicon wafers 8 to be scanned. After adsorption, the robotic arm 1 flips over, so that the robotic arm 1 and the silicon wafers 8 in the same group are mirror images of each other. Figure 1As shown, two silicon wafers 8 are arranged sequentially in a direction perpendicular to the horizontal plane. After adjusting the spacing between the two silicon wafers 8, the scanning head 7 is placed at the edge of the two silicon wafers 8. The scanning liquid storage structure 10 controls the flow of scanning liquid from the upper and lower outlets of the scanning head 7, ensuring that the scanning liquid from each outlet can contact the surface of the silicon wafer 8. Under the pressure of the scanning liquid storage structure 10, the scanning liquid at the outlet of the upper scanning head 7 does not fall but remains in contact with the surface of the silicon wafer 8.

[0066] When scanning begins, the stage 3 on the robotic arm 1 rotates the silicon wafer 8. At the same time, the robotic arm 1 moves horizontally, allowing the scanning head 7 to scan both silicon wafers 8 simultaneously. Optionally, the scanning head 7 can also move horizontally during the scanning process to achieve the same scanning effect on the silicon wafers 8.

[0067] After scanning, the scanning fluid is collected and tested through the scanning fluid storage structure 10. If the test results are normal, it indicates that both silicon wafers 8 tested in this batch are qualified. If the test results are abnormal, individual silicon wafers 8 can be tested to investigate the cause of the abnormality. When the silicon wafer surface metal ion collection device has multiple sets of robotic arms 1, it can correspond to multiple scanning components 2, thereby realizing the simultaneous scanning of 2n silicon wafers 8. This can greatly improve the efficiency of scanning silicon wafers 8, significantly reduce testing time, and speed up the production cycle.

[0068] It should be noted that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, since the embodiments are basically similar to the product embodiments, the descriptions are relatively simple, and the relevant parts can be referred to the descriptions of the product embodiments.

[0069] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as “comprising” or “including” mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as “connected” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as “upper,” “lower,” “left,” and “right” are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0070] It is understandable that when a component such as a layer, film, region, or substrate is referred to as being "above" or "below" another component, the component may be "directly" located "above" or "below" the other component, or there may be intermediate components present.

[0071] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0072] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A device for collecting metal ions on the surface of a silicon wafer, characterized by The application relates to a silicon wafer surface metal ion collection device, comprising the following steps: at least one set of mechanical arms, each set of mechanical arms comprising a pair of mirror-imaged platforms for fixing silicon wafers; a scanning assembly comprising a main body structure and a pair of mirror-imaged scanning heads arranged at one end of the main body structure, the scanning heads corresponding to the platforms one by one, and a scanning pipeline arranged in the main body structure and used for transmitting scanning liquid, the scanning pipeline being communicated with liquid outlets of the two scanning heads; a scanning liquid storage structure used for transmitting scanning liquid to the liquid outlets through the scanning pipeline under the action of pressure or recovering the scanning liquid from the liquid outlets through the scanning pipeline under the action of suction; the scanning head comprises two hinged leaves arranged at the liquid outlets, when the scanning liquid storage structure transmits scanning liquid to the liquid outlets through the scanning pipeline under the action of pressure, the two hinged leaves are opened under the action of pressure, and the scanning liquid flows out of the scanning pipeline to the liquid outlets; when the scanning liquid storage structure recovers the scanning liquid from the liquid outlets through the scanning pipeline under the action of suction, the two hinged leaves are closed under the action of suction, and the liquid outlets are closed; the scanning head is further provided with a ring of air holes surrounding the two hinged leaves and a gas supply assembly used for supplying gas to the air holes, the air holes are arranged in a direction towards the center of the liquid outlets, and when the scanning liquid flows out of the scanning pipeline to the liquid outlets, the gas supply assembly supplies gas to the air holes so that the scanning liquid is gathered in the center of the liquid outlets under the action of gas flow.

2. The apparatus according to claim 1, wherein the metal ion collector is a metal ion collector having a surface area of 0.1 to 1000 cm2. The platform can rotate around a central axis.

3. The apparatus according to claim 1, wherein the metal ion collector is a metal ion collector having a surface area of 0.1-1000 cm2. The platform is provided with a vacuum hole used for adsorbing a silicon wafer.

4. A method for collecting metal ions on the surface of a silicon wafer, characterized by, The application is applied to the silicon wafer surface metal ion collection device, and the method comprises the following steps: two silicon wafers are fixed on the platforms so as to be mirror-imaged; the interval between the two silicon wafers is adjusted, the scanning heads are controlled to be located between the two silicon wafers, scanning liquid is transmitted to the liquid outlets through the scanning pipeline under the action of pressure, and the scanning liquid of the liquid outlets of each scanning head respectively contacts the surface of a silicon wafer; the silicon wafers are scanned by the scanning heads, and after scanning, the scanning liquid is recovered from the liquid outlets through the scanning pipeline under the action of suction.

5. The method of claim 4, wherein the metal ions are collected on the surface of the silicon wafer. The method comprises the following steps: when scanning liquid is transmitted to the liquid outlets through the scanning pipeline under the action of pressure, the two hinged leaves are opened under the action of pressure, and the scanning liquid flows out of the scanning pipeline to the liquid outlets; when the scanning liquid is recovered from the liquid outlets through the scanning pipeline under the action of suction, the two hinged leaves are closed under the action of suction, and the liquid outlets are closed.

6. The method of claim 4, wherein the metal ions are collected on the surface of the silicon wafer. The method further comprises the following steps: when the scanning liquid flows out of the scanning pipeline to the liquid outlets, gas is supplied to the air holes by the gas supply assembly, so that the scanning liquid is gathered in the center of the liquid outlets under the action of gas flow.

7. The method of claim 4, wherein the metal ions are collected on the surface of the silicon wafer. The scanning of the silicon wafers by the scanning heads comprises the following steps: The carrier is controlled to rotate the silicon wafers, and the mechanical arm is controlled to move horizontally, so that the scanning assembly simultaneously scans the two silicon wafers.

8. The method of claim 4, wherein the silicon wafer surface is exposed to the metal ion solution for a period of time ranging from about 1 minute to about 24 hours. The scanning of the silicon wafers by the scanning head comprises: The carrier is controlled to rotate the silicon wafers, and the scanning assembly is controlled to move horizontally, so that the scanning assembly simultaneously scans the two silicon wafers.

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