CMP (Chemical Mechanical Polishing) finishing disc
By setting up annular grooves and drain holes on the CMP trimming plate, the polishing liquid is extracted by negative pressure, the problem of debris falling off of diamond particles being mixed into the polishing liquid is solved, achieving a more efficient removal effect and preventing contamination and scratches of the polishing sheet.
Patent Information
- Application Number
- CN202421832421.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-30
- Publication Date
- 2025-06-13
- Estimated Expiration
- 2034-07-30
AI Technical Summary
During the CMP process, the debris formed by the diamond particles on the surface of the trimming plate are mixed into the polishing liquid, resulting in the polishing liquid being untimely removed, resulting in the surface contamination and scratches of the polishing pad, affecting the wafer yield.
A CMP trimming disk is designed, with an annular groove and multiple liquid discharge holes on the disk body. Negative pressure is input through the liquid discharge holes to extract the polishing liquid from the annular grooves, and timely remove debris from diamond particles.
It effectively improves the removal effect of debris generated during chemical mechanical grinding, prevents surface contamination and scratches of the polishing sheet, and improves the trimming effect.
Smart Images
Figure CN222971901U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of semiconductor manufacturing equipment, in particular to a CMP dressing disk. Background Art
[0002] Chemical Mechanical Polishing (CMP) is a technology that combines chemical etching and mechanical grinding to perform a smoothing and trimming process on a silicon wafer or other substrate material during processing. It is one of the important links in the modern semiconductor manufacturing process. The purpose of the chemical mechanical polishing process is to remove the uneven parts on the surface of the wafer material and make the material surface reach atomic-level flatness. During the chemical mechanical polishing process, the removal of the wafer material is achieved by virtue of the relative movement between the polishing pad and the wafer material and the chemical etching effect of the polishing liquid. Among them, the polishing pad has functions such as storing and transporting the polishing liquid, removing debris generated during processing, and transmitting mechanical loads. During the CMP process, the performance of the polishing pad will gradually decline, resulting in a decline in polishing efficiency and polishing quality. Therefore, during the CMP process, a CMP dressing disk needs to be used to dress the polishing pad to ensure the processing performance of the polishing pad, so as to ensure the stability and repeatability of the CMP process. During the CMP process, after the dressing disk is used for a period of time, the diamond particles on its surface will occasionally fall off and break to form debris and mix into the polishing liquid. At this time, if the polishing liquid is not discharged in time, there will be risks such as surface contamination and scratching of the polished wafer, which greatly affects the wafer yield. Summary of the Utility Model
[0003] In view of this, in order to solve the problem of surface contamination and scratching of the polishing pad caused by the debris formed by the falling off and breaking of the diamond particles on the surface of the dressing disk and mixing into the polishing liquid and being unable to be discharged in time, an embodiment of the utility model provides a CMP dressing disk.
[0004] An embodiment of the utility model provides a CMP dressing disk, including:
[0005] A disk body;
[0006] A plurality of diamond particles are arranged in the middle of one side surface of the disk body;
[0007] An annular groove is arranged in the middle of the side surface where the diamond particles are located and is recessed relative to the side surface;
[0008] And a plurality of liquid discharge holes are dispersedly arranged in the annular groove. The liquid discharge holes penetrate through the disk body and extend to the other side surface of the disk body. The liquid discharge holes are used to input negative pressure to pump out the polishing liquid in the annular groove.
[0009] Further, the diamond particles include a dressing part and a connecting part connected to each other. The connecting part is fixedly connected to the disk body, and the dressing part is used to abut against the polishing pad.
[0010] Further, the disk body includes a base body and a diamond coating layer. The diamond coating layer is disposed on one side surface of the base body. The connecting portions of all diamond particles are embedded in the diamond coating layer, and the dressing portions of all diamond particles are exposed outside the diamond coating layer.
[0011] Further, the diamond coating layer is a metallic material.
[0012] Further, the diamond coating layer is a brazing filler metal or an electroplated coating layer.
[0013] Further, the annular groove is coaxially disposed with the disk body.
[0014] Further, the depth of the annular groove is less than the thickness of the disk body, and the diameter of the liquid discharge hole is less than the width of the annular groove.
[0015] Further, the width of the annular groove is 2.5 - 4 mm, and the diameter of the liquid discharge hole is 1 - 3 mm.
[0016] Further, the number of all liquid discharge holes is set to 4 - 8, and they are evenly spaced along the annular groove.
[0017] Further, the crystal form of the diamond particles is a six - octahedron structure or an octahedron structure.
[0018] The beneficial effects brought by the technical solution provided by the embodiment of the present utility model are as follows: For a CMP dressing disk of the present utility model, an annular groove is provided on the disk body of the dressing disk, and liquid discharge holes are opened in the annular groove. A negative pressure device is connected to the liquid discharge holes to input negative pressure to the liquid discharge holes. During the process of the dressing disk dressing the polishing pad, debris formed by the shedding and breaking of diamond particles is mixed into the polishing liquid and then enters the annular groove. Under the action of negative pressure, the polishing liquid is sucked out from the liquid discharge holes, and the debris generated during the chemical mechanical polishing process is timely discharged along with the polishing liquid, thereby improving the cleaning effect on the debris generated during the chemical mechanical polishing process, and further solving the problems such as surface contamination and scratching of the polished wafer caused by untimely discharge of the polishing liquid in the existing CMP process, and improving the dressing effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 is a top view of a CMP dressing disk of the present utility model;
[0020] Figure 2 is a cross - sectional view of a CMP dressing disk of the present utility model.
[0021] In the figure: 1. Disc body; 101. Substrate; 102. Diamond coating layer; 2. Annular groove; 3. Drain hole; 4. Diamond particle; 401. Connection part; 402. Dressing part. Detailed implementation manners
[0022] To make the objectives, technical solutions and advantages of the present utility model clearer, the following will further describe the embodiments of the present utility model with reference to the accompanying drawings. The following introduces a relatively optimal one among multiple possible embodiments of the present utility model, aiming to provide a basic understanding of the present utility model, but not aiming to identify the key or decisive elements of the present utility model or limit the scope to be protected.
[0023] In all the examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of the exemplary embodiments may have different values.
[0024] For technologies, methods and devices known to those of ordinary skill in the relevant art, detailed discussions may not be made, but under appropriate circumstances, the said technologies, methods and devices should be regarded as part of the description.
[0025] It should be noted that: Similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings. At the same time, it should be understood that, for the sake of convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationship.
[0026] In the description of the present utility model, it should be noted that the circuits, electronic components and modules involved in the present utility model are all prior art, and those skilled in the art can fully implement them without further elaboration. The content protected by the present utility model does not involve improvements to the internal structure and method either.
[0027] Furthermore, it should be noted that unless otherwise clearly specified and defined, the terms "installation" and "connection" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the communication inside two elements. 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.
[0028] Please refer to Figure 1 and 2 , an embodiment of the present utility model provides a CMP dressing disc, including a disc body 1, a plurality of diamond particles 4, an annular groove 2 and a plurality of drain holes 3.
[0029] The disk body 1 is mainly used for arranging the diamond particles 4. The disk body 1 includes a substrate 101 and a diamond coating layer 102. Among them, the substrate 101 is in a disk shape and is made of a stainless steel original sheet substrate 101 through precision machining. The diamond coating layer 102 is generally a metal material, such as a brazing filler metal or an electroplated coating layer.
[0030] All the diamond particles 4 are arranged in the middle of one side surface of the disk body 1. The diamond particles 4 include a dressing part 402 and a connecting part 401 connected to each other. The connecting part 401 is fixedly connected to the disk body 1, and the dressing part 402 is used to abut against a polishing pad to dress the polishing pad.
[0031] The diamond coating layer 102 is arranged on one side surface of the substrate 101. The connecting parts 401 of all the diamond particles 4 are embedded in the diamond coating layer 102, and the dressing parts 402 of all the diamond particles 4 are exposed outside the diamond coating layer 102.
[0032] The diamond particles 4 can be connected to the substrate 101 through a brazing-sintering process. In this embodiment, the diamond coating layer 102 is a brazing filler metal, and the brazing filler metal is selected as nickel-chromium alloy powder. First, a brazing filler metal with a certain and uniform thickness is coated on the processed substrate 101, and the diamond particles 4 are arranged on the surface of the substrate 101 according to the required arrangement density. Subsequently, vacuum sintering is carried out. In the vacuum sintering process, the brazing filler metal will fix the connecting parts 401 of the diamond particles 4 on the substrate 101 through a process of first melting and then solidifying, whereby the connecting parts 401 of all the diamond particles 4 can be embedded in the diamond coating layer 102.
[0033] The diamond particles 4 can be connected to the substrate 101 through an electroplating process. In some other embodiments, the diamond coating layer 102 is an electroplated coating layer, and the electroplated coating layer is selected as nickel-chromium alloy or nickel-cobalt alloy. The connecting parts 401 of all the diamond particles 4 are embedded in the diamond coating layer 102 through an electroplating process and are connected to the substrate 101.
[0034] The diamond particles 4 are generally selected as artificial diamond abrasive grains. The crystal form of the diamond particles 4 is a six-octahedron structure or an octahedron structure, the diamond particle size is 200 - 220 μm, and the arrangement density of the diamond particles 4 on the substrate 101 is 450 pieces per square centimeter.
[0035] The annular groove 2 is arranged in the middle of the side surface where the diamond particles 4 are located and is recessed relative to the side surface. The annular groove 2 is coaxially arranged with the disk body 1 and is located inside the edge of the disk body 1.
[0036] All the liquid discharge holes 3 are dispersedly arranged in the annular groove 2. Both the annular groove 2 and the liquid discharge holes 3 are precisely machined by a CNC machine tool.
[0037] The liquid discharge holes 3 penetrate through the disc body 1 and extend to the other surface of the disc body 1. One end of the liquid discharge hole 3 located on the other surface of the disc body 1 is used to input negative pressure to extract the polishing liquid in the annular groove 2. In order to achieve a uniform suction effect, all the liquid discharge holes 3 are evenly spaced along the annular groove 2. The depth of the annular groove 2 is less than the thickness of the disc body 1, and the diameter of the liquid discharge hole 3 is less than the width of the annular groove 2.
[0038] The size of the annular groove 2, as well as the size and quantity of the liquid discharge holes 3, can be flexibly set according to the specifications of the dressing disc in the actual application scenario. In some embodiments, the thickness of the disc body 1 is 5.55 mm, the depth of the annular groove 2 is 4 mm, the diameter width is 2.5 - 4 mm, the diameter of the liquid discharge hole 3 is 1 - 3 mm, and the quantity is set to 4 - 8.
[0039] During the CMP process, the CMP dressing disc is arranged above the polishing pad, so that the dressing part 402 of the diamond particles 4 is in contact with the polishing pad, and the liquid discharge holes 3 are connected to a negative pressure device through a drain pipe. During the process of the CMP dressing disc dressing the polishing pad, the debris shed from the diamond particles 4 mixes into the polishing liquid and then enters the annular groove 2. Under the action of negative pressure, the polishing liquid is sucked out from the liquid discharge holes 3, and the debris shed from the diamond particles 4 during the chemical mechanical polishing process is discharged in time along with the polishing liquid, preventing problems such as surface contamination and scratching of the polished wafer caused by the accidentally shed debris of the diamond particles 4.
[0040] In this article, the front, back, up, down and other orientation words are defined based on the positions of the components in the drawings and the positions of the components relative to each other, only for the sake of clarity and convenience in expressing the technical solution. It should be understood that they are relative concepts and can change accordingly according to different usage and placement methods. The use of the orientation words should not limit the scope of protection claimed in this application.
[0041] Without conflict, the above embodiments and the features in the embodiments in this article can be combined with each other. The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A CMP conditioning disc, characterized in that: include: Plate body; A plurality of diamond particles are arranged in the middle of one side surface of the disk; An annular groove is arranged in the middle of the side surface where the diamond particles are located and is recessed relative to the side surface; And a plurality of drainage holes are dispersedly arranged in the annular groove, the drainage holes penetrate the disk body and extend to the other side surface of the disk body, and the drainage holes are used to input negative pressure to extract the polishing liquid in the annular groove.
2. A CMP conditioning disc as claimed in claim 1, characterized in that: The diamond particles include a trimming portion and a connecting portion connected to each other, the connecting portion is fixedly connected to the disc body, and the trimming portion is used to abut against the polishing pad.
3. A CMP conditioning disc as claimed in claim 2, characterized in that: The disk body comprises a substrate and a diamond coating layer, wherein the diamond coating layer is arranged on one side surface of the substrate, the connecting parts of all diamond particles are embedded in the diamond coating layer, and the trimming parts of all diamond particles are exposed outside the diamond coating layer.
4. A CMP conditioning disc as claimed in claim 3, characterized in that: The diamond coating layer is made of metal material.
5. A CMP conditioning disc as claimed in claim 4, characterized in that: The diamond coating layer is a brazing material or an electroplating coating layer.
6. A CMP conditioning disc according to any one of claims 1 to 5, characterized in that: The annular groove is coaxially arranged with the disc body.
7. A CMP conditioning disc as claimed in claim 1, characterized in that: The depth of the annular groove is smaller than the thickness of the disc body, and the diameter of the drainage hole is smaller than the width of the annular groove.
8. A CMP conditioning disc as claimed in claim 7, characterized in that: The diameter width of the annular groove is 2.5-4 mm, and the diameter of the drainage hole is 1-3 mm.
9. A CMP conditioning disc as claimed in claim 1, characterized in that: The number of all drainage holes is set to 4 to 8, and they are evenly spaced along the annular groove.
10. A CMP conditioning disc as claimed in claim 1, characterized in that: The crystal form of the diamond particles is a hexahedral structure or an octahedral structure.