Wafer bearing assembly and wafer polishing system

Abstract

The utility model provides a wafer bearing assembly and a wafer polishing system, the wafer bearing assembly comprises a shell, a bearing seat and an ultrasonic wave generating device, the shell is provided with a containing cavity used for containing cleaning fluid, the bearing seat is arranged in the shell, the bearing seat is used for bearing a wafer, and the ultrasonic wave generating device is arranged in the containing cavity. The ultrasonic generating device is used for generating ultrasonic waves in the cleaning liquid in the shell so as to clean the wafer and / or the grinding head. According to the wafer bearing assembly, ultrasonic waves are generated in the cleaning liquid in the containing cavity of the shell through the ultrasonic wave generating device, particles on the surface of the wafer and / or the grinding head can be fully cleaned in the wafer grinding unit, and the situation that the wafer is scratched by the grinding head in the grinding process is reduced or avoided; and particles on the surface of the wafer can be removed in time when the wafer is ground and flushed, so that the yield of the wafer is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of semiconductor manufacturing, and more specifically, relates to a wafer carrier assembly and a wafer polishing system. Background Art

[0002] In the semiconductor manufacturing process, the wafer carrier assembly in the chemical mechanical polishing device plays the roles of loading and unloading wafers, micro-cleaning the wafers and the polishing head. Figure 1 For the top view of the existing wafer carrier assembly, please refer to Figure 1 As shown, the existing chemical mechanical polishing device performs micro-cleaning on the polishing head and the wafer through the sector-shaped or conical nozzles on the wafer carrier assembly. For example, the polishing head is micro-cleaned through the nozzles before the wafer is loaded onto the wafer carrier assembly, and the polishing head is micro-cleaned through the nozzles after the wafer is unloaded onto the polishing head; the wafer is micro-cleaned through the nozzles after the wafer polishing is completed.

[0003] Because the cleaning surface of the nozzles cannot completely cover the surface of the polishing head or the wafer, flushing the polishing head or the wafer only through the nozzles will result in insufficient flushing ability. However, in the wafer polishing unit, if the polishing head is not flushed sufficiently, the polishing head will scratch the wafer during the polishing process. If the particulate matter on the wafer surface cannot be removed in time when the wafer is flushed, it will affect the wafer yield. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a wafer carrier assembly and a wafer polishing system, and the wafer carrier assembly can fully remove the particulate matter on the surface of the polishing head and / or the wafer in the wafer polishing unit.

[0005] To achieve the above purpose, the technical solution adopted by the utility model is: in the first aspect of the utility model, a wafer carrier assembly is provided, including:

[0006] A housing, a carrier seat, and an ultrasonic generating device;

[0007] The housing has an accommodating cavity for containing a cleaning liquid. The carrier seat is arranged in the housing and is used for carrying a wafer. The ultrasonic generating device is used to generate ultrasonic waves in the cleaning liquid in the accommodating cavity to clean the wafer and / or the polishing head.

[0008] In one embodiment, it further includes an edge ring and a nozzle. The edge ring is arranged on the carrier seat, and the nozzle is used to clean the gap between the carrier seat and the edge ring.

[0009] In one embodiment, it further includes a liquid storage tank. The liquid storage tank is communicated with the accommodating cavity for storing the cleaning liquid. An inlet pipeline is arranged between the liquid storage tank and the housing, and the inlet pipeline is used to transport the cleaning liquid in the liquid storage tank to the accommodating cavity.

[0010] In one embodiment, a liquid return pipe is provided between the liquid storage tank and the housing, and the liquid return pipe is used to transport the cleaning liquid in the accommodation cavity to the liquid storage tank; a filter is provided on the liquid inlet pipe.

[0011] In one embodiment, a plurality of injection ports are provided on the side wall of the liquid storage tank; drain pipes are provided at the bottom of the housing and the bottom of the liquid storage tank.

[0012] In one embodiment, drain pipes are provided at the bottom of the housing and the bottom of the liquid storage tank.

[0013] In one embodiment, a first liquid level sensor and a second liquid level sensor are provided inside the accommodation cavity. The first liquid level sensor is provided at a preset low liquid level of the accommodation cavity, and the second liquid level sensor is provided at a preset high liquid level of the accommodation cavity. Both the first liquid level sensor and the second liquid level sensor are electrically connected to the liquid infusion device of the liquid storage tank.

[0014] In one embodiment, the second liquid level sensor is electrically connected to the ultrasonic generating device. When the second liquid level sensor detects the preset high liquid level, the ultrasonic generating device is started.

[0015] In one embodiment, the ultrasonic generating device includes an ultrasonic generator, an ultrasonic transducer, and a vibration panel. The ultrasonic generator is connected to the ultrasonic transducer, the ultrasonic transducer is connected to the vibration panel, and the vibration panel is provided on the outer side or the inner side of the bottom of the housing.

[0016] In one embodiment, the carrier seat can move up and down relative to the housing in the vertical direction, and the grinding head can move up and down in the vertical direction.

[0017] The second aspect of the present utility model provides a wafer polishing system, including the wafer carrier assembly as described above.

[0018] The wafer carrier assembly provided by the present utility model includes a housing, a carrier seat, and an ultrasonic generating device. The housing has an accommodation cavity for containing a cleaning liquid. The carrier seat is arranged inside the housing and is used to carry a wafer. The ultrasonic generating device is used to generate ultrasonic waves in the cleaning liquid in the accommodation cavity to clean the wafer and / or the grinding head. Through the ultrasonic generating device, ultrasonic waves are generated in the cleaning liquid in the accommodation cavity of the housing, and the surface particles of the wafer and / or the grinding head can be fully cleaned in the wafer grinding unit, reducing or avoiding the wafer being scratched by the grinding head during the grinding process. When the wafer is rinsed after grinding, the surface particles of the wafer can be removed in time, improving the yield of the wafer. Description of the Drawings

[0019] To more clearly illustrate the technical solutions in the embodiments of the present utility model, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a top view of an existing wafer carrier assembly;

[0021] Figure 2 It is a schematic structural diagram of the wafer carrier assembly and the grinding head provided by the embodiment of the present utility model;

[0022] Figure 3 It is a top view of a partial structure of the wafer carrier assembly provided by the embodiment of the present utility model;

[0023] Figure 4 It is a front view of the housing of the wafer carrier assembly and the grinding head provided by the embodiment of the present utility model.

[0024] Among them, the reference numerals in the drawings are as follows:

[0025] 1 - housing; 2 - carrier seat; 3 - ultrasonic generating device; 4 - grinding head; 5 - liquid storage tank; 6 - nozzle; 7 - wafer; 11 - first liquid level sensor; 12 - second liquid level sensor; 31 - ultrasonic generator; 32 - ultrasonic transducer; 33 - vibration panel; 51 - liquid inlet pipe; 52 - liquid return pipe; 53 - filter; 54 - injection port. Specific embodiments

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present utility model in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present utility model.

[0027] In the description of the present utility model, it should be understood that the terms "including" and "having" and any variations thereof used herein are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0028] It should be understood that the orientation or positional relationship indicated by terms such as "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0029] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. It should be understood that the term "and / or" used herein is merely a description of the associated relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In the description of the present invention, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0030] The following will specifically describe the wafer carrier assembly and the wafer polishing system provided by the present invention with reference to specific embodiments.

[0031] Figure 2 It is a schematic structural diagram of the wafer carrier assembly and the grinding head provided by the embodiment of the present invention. Figure 3 It is a top view of the partial structure of the wafer carrier assembly provided by the embodiment of the present invention. Figure 4 It is a front view of the housing and the grinding head of the wafer carrier assembly provided by the embodiment of the present invention. Please refer to Figures 2 - 4 In the first aspect of this embodiment, a wafer carrier assembly is provided, including a housing 1, a carrier seat 2, and an ultrasonic generating device 3.

[0032] The housing 1 has an accommodating cavity for holding a cleaning liquid. The carrier seat 2 is disposed inside the housing 1. The carrier seat 2 is used for carrying a wafer 7 ( Figure 2 in [the figure], the wafer 7 is located directly below the grinding head 4), and the ultrasonic generating device 3 is used to generate ultrasonic waves in the cleaning liquid in the accommodating cavity of the housing 1 to clean the wafer 7 and / or the grinding head 4.

[0033] The carrier base 2 of this embodiment is disposed within the housing 1. The carrier base 2 is used to carry the wafer 7. The carrier base 2 can be a structure for carrying wafers used in the prior art. This embodiment does not impose any special restrictions on the specific structure and dimensions of the carrier base 2. The accommodation cavity of the housing 1 of this embodiment is used to hold the cleaning liquid for cleaning the wafer 7 and the polishing head 4. This embodiment does not impose any special restrictions on the specific dimensions of the housing 1, and those skilled in the art can preset according to actual needs. The polishing head 4 of this embodiment is a polishing head used to polish the wafer 7 in the prior art. This embodiment does not impose any special restrictions on the structure and dimensions of the polishing head 4.

[0034] The ultrasonic generating device 3 of this embodiment is used to generate ultrasonic waves in the cleaning liquid within the accommodation cavity of the housing 1 to clean the wafer 7 and / or the polishing head 4. Exemplarily, the polishing head 4 is cleaned by ultrasonic waves before the wafer 7 is loaded onto the carrier base 2, or the polishing head 4 is cleaned by ultrasonic waves after the wafer 7 is unloaded from the polishing head 4; after the wafer 7 is polished, the wafer 7 and the polishing head 4 are cleaned together by ultrasonic waves.

[0035] This embodiment does not impose any special restrictions on the specific structure of the ultrasonic generating device 3. The ultrasonic generating device 3 is an ultrasonic generating device applied in the prior art. In the existing chemical mechanical polishing device, in the wafer polishing unit, only the nozzle on the carrier assembly can be used to clean the wafer 7 and the polishing head 4. Since the cleaning surface of the nozzle cannot completely cover the surface of the polishing head 4 or the wafer 7, rinsing the polishing head 4 or the wafer 7 only through the nozzle will result in insufficient rinsing ability. If the polishing head 4 is not rinsed thoroughly, it will scratch the wafer 7 during the polishing process. If the particulate matter on the surface of the wafer 7 cannot be removed in time when the wafer 7 is rinsed, it will affect the yield of the wafer 7. In this embodiment, by using the ultrasonic generating device 3 in the wafer polishing unit to generate ultrasonic waves in the cleaning liquid within the accommodation cavity of the housing 1 to clean the wafer 7 and / or the polishing head 4, the particulate matter on the surfaces of the polishing head 4 and the wafer 7 can be thoroughly cleaned, avoiding the wafer 7 from being scratched by the polishing head 4 in the polishing unit and improving the qualification rate of the wafer 7 in the polishing unit.

[0036] The wafer carrier assembly provided by the embodiment of the present utility model includes a housing, a carrier base, and an ultrasonic generating device. The housing has an accommodation cavity for holding the cleaning liquid. The carrier base is disposed within the housing and is used to carry the wafer. The ultrasonic generating device is used to generate ultrasonic waves in the cleaning liquid within the housing to clean the wafer and / or the polishing head. Through the ultrasonic generating device, this wafer carrier assembly generates ultrasonic waves in the cleaning liquid within the accommodation cavity of the housing, and in the wafer polishing unit, it can thoroughly clean the particulate matter on the surface of the wafer and / or the polishing head, reducing or avoiding the wafer from being scratched by the polishing head during the polishing process, and enabling the particulate matter on the surface of the wafer to be removed in time when the wafer is rinsed after polishing, thereby improving the yield of the wafer.

[0037] Please refer to Figure 2 and Figure 3 In a specific embodiment, the wafer carrier assembly further includes an edge ring and a nozzle 6. The edge ring is disposed on the carrier base 2, and the nozzle 6 is used to clean the gap between the carrier base 2 and the edge ring. The edge ring in this embodiment plays a role in positioning the wafer 7 during the loading process of the wafer 7. By providing the nozzle 6 in this embodiment, the gap between the carrier base 2 and the edge ring can be rinsed more effectively. For example, while performing ultrasonic cleaning, the gap between the carrier base 2 and the edge ring is jet-rinsed through the nozzle 6, which can better clean the contaminated particulate matter in the gap between the carrier base 2 and the edge ring.

[0038] Please refer to Figure 2 In a specific embodiment, the wafer carrier assembly of this embodiment further includes a liquid storage tank 5. The liquid storage tank 5 is communicated with the accommodating cavity of the housing 1 for storing cleaning liquid. A liquid inlet pipe 51 is provided between the liquid storage tank 5 and the housing 1, and the liquid inlet pipe 51 is used to convey the cleaning liquid in the liquid storage tank 5 to the accommodating cavity. By providing the liquid storage tank 5 in this embodiment, the cleaning liquid is conveyed through the liquid inlet pipe 51 connecting the housing 1 and the liquid storage tank 5, and the cleaning liquid can be replenished at any time after the liquid level of the cleaning liquid decreases. A liquid conveying device, such as a liquid infusion pump, is provided in the liquid storage tank 5 of this embodiment for conveying the cleaning liquid in the liquid storage tank 5 to the accommodating cavity.

[0039] A liquid return pipe 52 is provided between the liquid storage tank 5 and the housing 1, and a filter 53 is provided on the liquid inlet pipe 51. The liquid return pipe 52 is used to convey the cleaning liquid in the accommodating cavity of the housing 1 to the liquid storage tank 5. By providing the liquid return pipe 52 in this embodiment, the cleaning liquid in the housing 1 can be conveyed to the liquid storage tank 5 through the liquid return pipe 52 after cleaning is completed, avoiding waste of the cleaning liquid. A liquid infusion pump for conveying the cleaning liquid in the housing 1 to the liquid storage tank is provided in the housing 1 of this embodiment. By providing the filter 53 on the liquid inlet pipe 51 in this embodiment, when the cleaning liquid in the liquid storage tank 5 enters the accommodating cavity of the housing 1, the filter 53 filters the cleaning liquid, ensuring the cleanliness of the cleaning liquid in the accommodating cavity of the housing 1.

[0040] Furthermore, a plurality of injection ports 54 are provided on the side wall of the liquid storage tank 5. A plurality of injection ports 54 are provided on the side wall of the liquid storage tank 5 in this embodiment, which is convenient for conveying different cleaning liquids in the liquid storage tank 5. The cleaning liquid in this embodiment is a chemical cleaning liquid, which can thoroughly remove the contaminants on the surface of the wafer 7 and / or the polishing head 4. The cleaning liquid needs to be made with different chemical reagents in different proportions. By providing a plurality of injection ports 54 in this embodiment, various required chemical reagents can be input simultaneously through each injection port 54 to make the cleaning liquid.

[0041] Furthermore, drain pipes are provided at the bottom of the housing 1 and the bottom of the liquid storage tank 5. In this embodiment, by providing a drain pipe at the bottom of the housing 1, in the case of debris during the wafer grinding process, the cleaning liquid in the accommodation chamber can be directly discharged through the drain pipe at the bottom of the housing 1. In this embodiment, by providing a drain pipe at the bottom of the liquid storage tank 5, after the cleaning liquid is used multiple times, the cleaning liquid in the liquid storage tank 5 can be discharged through the drain pipe at the bottom of the liquid storage tank 5.

[0042] Furthermore, a first liquid level sensor 11 and a second liquid level sensor 12 are provided inside the housing 1. The first liquid level sensor 11 is provided at a preset low liquid level of the accommodation chamber, and the second liquid level sensor 12 is provided at a preset high liquid level of the accommodation chamber. Both the first liquid level sensor 11 and the second liquid level sensor 12 are electrically connected to the liquid infusion device of the liquid storage tank 5. In this embodiment, by providing the first liquid level sensor 11 and the second liquid level sensor 12 inside the housing 1, when the first liquid level sensor 11 detects a low liquid level, the liquid infusion device of the liquid storage tank 5 is started to transport the cleaning liquid in the liquid storage tank 5 to the housing 1. When the second liquid level sensor 12 detects a high liquid level, the liquid infusion device of the liquid storage tank 5 stops supplying liquid.

[0043] Furthermore, the second liquid level sensor 12 is electrically connected to the ultrasonic generating device 3. When the second liquid level sensor 12 detects the preset high liquid level, the ultrasonic generating device 3 is started. The ultrasonic generating device 3 in this embodiment is automatically started when the second liquid level sensor 12 detects the preset high liquid level, which can reduce manual intervention, thereby saving labor costs. At the same time, it can also ensure the continuous and stable operation of the device and improve work efficiency.

[0044] Please refer to Figure 2 , in the above embodiment, the ultrasonic generating device 3 includes an ultrasonic generator 31, an ultrasonic transducer 32, and a vibration panel 33. The ultrasonic generator 31 is connected to the ultrasonic transducer 32, the ultrasonic transducer 32 is connected to the vibration panel 33, and the vibration panel 33 is provided on the outer or inner side of the bottom of the housing 1. In this embodiment, the ultrasonic generator 31 makes the vibration panel 33 vibrate through the ultrasonic transducer 32 to generate bubbles in the accommodation chamber of the housing 1. After the bubbles expand, they impact the surface of the grinding head 4 and / or the wafer 7 and cause the bubbles to burst, thereby taking away the particulate matter on the surface of the grinding head 4 and / or the wafer 7. In this embodiment, by ultrasonic cleaning the grinding head 4, it can ensure that the wafer 7 is less scratched during the grinding process. By ultrasonic cleaning the wafer 7, the particulate matter on the surface of the wafer 7 can be removed in a timely and effective manner, thereby improving the product yield.

[0045] In the above embodiments, the housing 1 or the carrier 2 can be lifted and lowered in the vertical direction, which is convenient for loading and unloading the wafer 7 on the carrier 2. For example, when loading and unloading the wafer 7, the carrier 2 is raised, and when cleaning the wafer 7 and / or the polishing head 4, the carrier 2 is lowered. The polishing head 4 can be lifted and lowered in the vertical direction, which is convenient for adjusting the positions of the polishing head 4 and the cleaning liquid.

[0046] In the second aspect of this embodiment, a wafer polishing system is provided, and the wafer polishing system includes the wafer carrier assembly described in the above embodiments.

[0047] For example, the wafer carrier assembly includes: a housing, a carrier, and an ultrasonic generating device;

[0048] The housing has a receiving cavity for containing the cleaning liquid. The carrier is disposed in the housing. The carrier is used for carrying the wafer. The ultrasonic generating device is used for generating ultrasonic waves in the cleaning liquid in the housing to clean the wafer and / or the polishing head.

[0049] The wafer polishing system provided by the embodiments of the present invention includes the above wafer carrier assembly. The wafer carrier assembly includes a housing, a carrier, and an ultrasonic generating device. The housing has a receiving cavity for containing the cleaning liquid. The carrier is disposed in the housing. The carrier is used for carrying the wafer. The ultrasonic generating device is used for generating ultrasonic waves in the cleaning liquid in the housing to clean the wafer and / or the polishing head. The wafer carrier assembly generates ultrasonic waves in the cleaning liquid in the receiving cavity of the housing through the ultrasonic generating device, and can fully clean the particulate matters on the surface of the wafer and / or the polishing head in the wafer grinding unit, reducing or avoiding the wafer being scratched by the polishing head during the grinding process, and being able to timely remove the particulate matters on the surface of the wafer when the wafer is rinsed after grinding is completed, improving the yield of the wafer.

[0050] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wafer carrier assembly, characterized in that, Comprising: A housing, a carrier seat, and an ultrasonic generating device; The housing has a receiving cavity for containing a cleaning liquid. The carrier seat is disposed inside the housing and is used for carrying a wafer. The ultrasonic generating device is used to generate ultrasonic waves in the cleaning liquid within the receiving cavity to clean the wafer and / or the polishing head.

2. The wafer carrier assembly according to claim 1, wherein, It further includes an edge ring and a nozzle. The edge ring is disposed on the carrier seat, and the nozzle is used to clean the gap between the carrier seat and the edge ring.

3. The wafer carrier assembly according to claim 1, wherein, It further includes a liquid storage tank. The liquid storage tank is communicated with the receiving cavity for storing the cleaning liquid. A liquid inlet pipe is provided between the liquid storage tank and the housing, and the liquid inlet pipe is used to convey the cleaning liquid in the liquid storage tank to the receiving cavity.

4. The wafer carrier assembly according to claim 3, wherein, A liquid return pipe is provided between the liquid storage tank and the housing, and the liquid return pipe is used to convey the cleaning liquid in the receiving cavity to the liquid storage tank; A filter is provided on the liquid inlet pipe.

5. The wafer carrier assembly according to claim 4, wherein A plurality of injection ports are provided on the side wall of the liquid storage tank; drain pipes are provided at the bottom of the housing and the bottom of the liquid storage tank.

6. The wafer carrier assembly according to claim 5, wherein, A first liquid level sensor and a second liquid level sensor are disposed inside the receiving cavity. The first liquid level sensor is disposed at a preset low liquid level of the receiving cavity, and the second liquid level sensor is disposed at a preset high liquid level of the receiving cavity. Both the first liquid level sensor and the second liquid level sensor are electrically connected to the liquid infusion device of the liquid storage tank.

7. The wafer carrier assembly according to claim 6, wherein The second liquid level sensor is electrically connected to the ultrasonic generating device. When the second liquid level sensor detects the preset high liquid level, the ultrasonic generating device starts.

8. The wafer carrier assembly according to any one of claims 1-7, characterized in that, The ultrasonic generating device includes an ultrasonic generator, an ultrasonic transducer, and a vibration panel. The ultrasonic generator is connected to the ultrasonic transducer, the ultrasonic transducer is connected to the vibration panel, and the vibration panel is disposed outside or inside the bottom of the housing.

9. The wafer carrier assembly according to claim 8, wherein, The carrier seat can be lifted and lowered relative to the housing in the vertical direction, and the polishing head can be lifted and lowered in the vertical direction.

10. A wafer polishing system, characterized in that, Comprising the wafer carrier assembly according to any one of claims 1-9.

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