Liquid drainage system of CMP (Chemical Mechanical Polishing) equipment

Abstract

The utility model discloses a liquid drainage system of CMP (chemical mechanical polishing) equipment, which comprises a grinding liquid drainage pipeline used for draining grinding liquid consumed by the CMP equipment during the CMP process, and the grinding liquid is used for grinding wafers used for preparing semiconductor devices in the CMP process; the cleaning liquid discharging pipeline is used for discharging cleaning liquid consumed by the CMP equipment in the CMP process, the cleaning liquid is used for cleaning a grinding disc of the CMP equipment in the CMP process, and the cleaning liquid discharging pipeline is not communicated with the grinding liquid discharging pipeline; wherein the grinding fluid drainage pipeline and the cleaning fluid drainage pipeline are respectively communicated with the main drainage pipeline, at least two flanges are arranged in the grinding fluid drainage pipeline, and a filter screen is arranged in each flange. According to the utility model, the convenience of cleaning and maintaining the liquid drainage system is improved on the basis of reducing the blockage of the liquid drainage system.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor devices and integrated circuits, and particularly relates to a liquid drainage system of a CMP device. Background Technique

[0002] The chemical mechanical polishing (CMP) process is an important process in the manufacturing of semiconductor devices. It uses the synergistic effect of chemical corrosion and mechanical polishing to planarize semiconductor wafers, effectively taking into account the local and global flatness of semiconductor devices.

[0003] Taking the CMP process of metallic copper (Cu) as an example, after forming a metallic copper layer through the electro-coated plating (ECP) process, the CMP process is then carried out to remove the metallic copper layer in areas other than the metal wiring on the wafer. By-products generated in the CMP process are prone to forming complexes and clogging the liquid drainage pipelines of the CMP device.

[0004] Reference Figure 1 , which shows a schematic diagram of the liquid drainage system of a CMP device provided in the related art. Exemplarily, as Figure 1 shown, the CMP device 100 has two liquid drainage pipelines, namely a polishing drain 110 and a cleaner drain 120. The polishing liquid and the cleaning liquid are respectively collected into the main liquid drainage pipeline 200 through the polishing drain 110 and the cleaner drain 120.

[0005] However, since the sinking type filter screens are usually adopted in the liquid drainage pipelines of the CMP devices provided in the related art (especially the CMP devices produced by Applied Materials, AMAT, USA), the number of mesh openings is small and the anti-clogging ability is poor. At the same time, since the polishing drain and the cleaner drain are connected and the polishing liquid and the cleaning liquid are collected and then discharged, it is easy to cause the filter screen and the liquid drainage pipeline to be clogged, and further cause liquid accumulation and water leakage. Summary of the Invention

[0006] The utility model provides a liquid drainage system of a CMP device, which can solve the problem that the liquid drainage system of the CMP device provided in the related art is prone to causing pipeline blockage. The liquid drainage system includes:

[0007] The polishing liquid consumed, which is used to polish the wafer for manufacturing semiconductor devices in the CMP process;

[0008] The cleaning liquid drainage pipe is used to drain the cleaning liquid consumed by the CMP equipment during the CMP process. The cleaning liquid is used to clean the polishing pad of the CMP equipment during the CMP process, and the cleaning liquid drainage pipe is not connected to the abrasive liquid drainage pipe.

[0009] Among them, the abrasive liquid drainage pipe and the cleaning liquid drainage pipe are respectively connected to the main drainage pipe. At least two flanges are provided in the abrasive liquid drainage pipe, and a filter screen is provided in each flange.

[0010] In some embodiments, the total area of the holes of the filter screen is larger than the cross-sectional area of the abrasive liquid drainage pipe.

[0011] In some embodiments, the total area of the holes of the filter screen is larger than 4 times the cross-sectional area of the abrasive liquid drainage pipe.

[0012] In some embodiments, the filter screen is a cylinder, and both bottom surfaces of the cylinder have openings, and the diameter of the openings is equal to the diameter of the abrasive liquid drainage pipe.

[0013] In some embodiments, the position of one flange is close to the CMP equipment, and the position of the other flange is close to the main drainage pipe.

[0014] In some embodiments, a copper metal layer is formed on the wafer.

[0015] In some embodiments, the copper metal layer is formed by an electroplating process.

[0016] The technical solution provided by the present invention has at least the following advantages:

[0017] By removing the connecting pipe between the abrasive liquid drainage pipe and the cleaning liquid drainage pipe in the drainage system of the CMP equipment, while preventing the consumed abrasive liquid and cleaning liquid from gathering, by installing detachable flanges in the abrasive liquid drainage pipe and setting the filter screen in the flanges, the convenience of cleaning and maintaining the drainage system is improved on the basis of reducing the blockage of the drainage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 It is a schematic diagram of the drainage system of the CMP equipment provided in the related art;

[0020] Figure 2 It is a schematic diagram of the liquid discharge system of a CMP device provided by an exemplary embodiment of the present application. Detailed implementation manners

[0021] Next, the technical solutions in the present utility model will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present utility model, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0022] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model 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 cannot be understood as a limitation of the present utility model. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0023] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can also be the communication inside two elements. It can be a wireless connection or a wired connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0024] In addition, the technical features involved in different embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0025] Refer to Figure 2 , which shows a schematic diagram of the liquid discharge system of a CMP device provided by an exemplary embodiment of the present application. The CMP device can be a CMP device produced by Applied Materials, Inc. in the United States, as Figure 2 shown. The liquid discharge system includes:

[0026] The abrasive liquid drainage pipe 111 is used to drain the abrasive liquid consumed by the CMP device 101 during the CMP process. The abrasive liquid is used to grind the wafer for fabricating semiconductor devices during the CMP process. Among them, a copper metal layer is formed on the wafer, and the copper metal layer is formed by an electroplating process.

[0027] The cleaning liquid drainage pipe 112 is used to drain the cleaning liquid consumed by the CMP device 101 during the CMP process. The cleaning liquid is used to clean the polishing pad of the CMP device ( Figure 2 (not shown in the figure) during the CMP process. The cleaning liquid drainage pipe 111 and the abrasive liquid drainage pipe 112 are not connected.

[0028] Among them, the abrasive liquid drainage pipe 111 and the cleaning liquid drainage pipe 112 are respectively connected to the main drainage pipe 201. At least two flanges are provided in the abrasive liquid drainage pipe 111, and a filter screen is provided in each flange. Figure 2 In the figure, two flanges are provided in the abrasive liquid drainage pipe 111 (the flange 1111 close to the CMP device 101 and the flange 1112 close to the main drainage pipe 201) for exemplary illustration. In actual applications, the number and position of the flanges can be set according to requirements. Since flanges are provided in the abrasive liquid drainage pipe 111 and the filter screen is provided in the flanges, the filter screen can be disassembled and cleaned more conveniently.

[0029] Among them, the filter screen is a cylinder. The two bottom surfaces of the cylinder have openings, and the diameter of the openings is equal to the diameter of the abrasive liquid drainage pipe. The cylinder is covered with holes. Since the filter screen is in a three-dimensional cylinder shape, its anti-blocking effect is stronger than that of the sunken filter screen. Optionally, the total area of the holes of the filter screen is larger than the cross-sectional area of the abrasive liquid drainage pipe 111, so as to further reduce blockage; further, the total area of the holes of the filter screen is more than 4 times the cross-sectional area of the abrasive liquid drainage pipe 111.

[0030] In summary, in the embodiment of the present application, by removing the connecting pipe between the abrasive liquid drainage pipe and the cleaning liquid drainage pipe in the drainage system of the CMP device, the consumed abrasive liquid and cleaning liquid no longer converge. At the same time, by installing detachable flanges in the abrasive liquid drainage pipe and setting the filter screen in the flanges, the convenience of cleaning and maintaining the drainage system is improved on the basis of reducing the blockage of the drainage system.

[0031] Obviously, the above embodiments are merely examples given for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of this utility model.

Claims

1. A drainage system for a CMP device, characterized in that: include: A grinding liquid discharge pipe, wherein the grinding liquid discharge pipe is used to discharge the grinding liquid consumed by the CMP device when performing a CMP process, wherein the grinding liquid is used to grind wafers for preparing semiconductor devices in the CMP process; a cleaning liquid drainage pipeline, the cleaning liquid drainage pipeline is used to discharge the cleaning liquid consumed by the CMP device when performing a CMP process, the cleaning liquid is used to clean the grinding disk of the CMP device during the CMP process, and the cleaning liquid drainage pipeline is not connected to the grinding liquid drainage pipeline; The grinding liquid drainage pipeline and the cleaning liquid drainage pipeline are respectively connected to the main drainage pipeline, and at least two flanges are arranged in the grinding liquid drainage pipeline, and a filter is arranged in each flange.

2. The drainage system according to claim 1, characterized in that: The total area of ​​the holes of the filter screen is larger than the cross-sectional area of ​​the grinding liquid discharge pipe.

3. The drainage system according to claim 2, characterized in that: The total area of ​​the holes of the filter screen is greater than 4 times the cross-sectional area of ​​the grinding liquid discharge pipe.

4. The drainage system according to claim 3, characterized in that: The filter screen is a cylinder, and two bottom surfaces of the cylinder have openings, and the diameter of the openings is equal to the diameter of the grinding liquid discharge pipe.

5. The drainage system according to claim 4, characterized in that: The polishing liquid drainage pipeline is provided with two flanges, one flange is located close to the CMP device, and the other flange is located close to the main drainage pipeline.

6. The drainage system according to any one of claims 1 to 5, characterized in that: A copper metal layer is formed on the wafer.

7. The drainage system according to claim 6, characterized in that: The copper metal layer is formed by an electroplating process.

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