Grinding device

Abstract

The invention provides a grinding device which comprises a grinding pad and a grinding table, the grinding pad is placed on the grinding table, and the grinding table drives the grinding pad to rotate synchronously; a to-be-processed wafer, wherein the to-be-processed wafer needs to be subjected to grinding of a metal structure; the wafer fixing device is used for fixing a wafer to be processed; the grinding and finishing disc comprises a substrate, an isolation layer and protruding grinding particles are arranged on the substrate, a metal ion supplementing structure made of the same material as the metal structure is further formed on the substrate, and the metal ion supplementing structure is used for supplementing metal ions when the grinding machine table is in a vacant state or a test wafer is ground. The grinding pad is ground to maintain the roughness of the grinding pad, and meanwhile the metal ion supplementing structure is ground to generate metal ions; and the grinding material spray head is used for spraying grinding liquid and / or purified water. According to the invention, new metal ions are always generated on the grinding finishing disc, and the whole environment is kept consistent, so that the chemical reaction is always in a stable state, and a product sheet is always kept at a relatively high and stable grinding rate in the grinding process.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a grinding device. Background Art

[0002] In the existing Cu CMP (chemical mechanical planarization) polishing process, the polishing rate is often unstable, resulting in abnormally high or low film thickness of the product. In severe cases, the resistance fails to meet the predetermined quality standard or acceptance range, resulting in product scrapping.

[0003] After analyzing the data, it was found that the grinding rate was particularly unstable after the machine was idle (the machine can be used normally, but no product is running and the machine is in an idle state). Even when running test wafers, there was still an abnormal grinding rate for the first product (the grinding rate of the 1st to 5th test wafers gradually increased, and the grinding rate tended to be stable after the 6th wafer).

[0004] In order to solve the above problems, a new type of grinding device needs to be proposed. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a grinding device for solving the problem of unstable grinding rate after the machine is in an idle state in the prior art.

[0006] To achieve the above object and other related objects, the present invention provides a grinding device, comprising:

[0007] A grinding pad and a grinding table, wherein the grinding pad is placed on the grinding table, and the grinding table drives the grinding pad to rotate synchronously;

[0008] A wafer to be processed, wherein the wafer to be processed needs to be ground with a metal structure;

[0009] A wafer fixing device, used for fixing the wafer to be processed;

[0010] A grinding and dressing disc, the grinding and dressing disc comprising a substrate, an isolation layer and protruding grinding particles are arranged on the substrate, and a metal ion supplement structure made of the same material as the metal structure is formed on the substrate, which is used for grinding the grinding pad to maintain its roughness and grinding the metal ion supplement structure to generate metal ions when the grinding machine is in an idle state;

[0011] An abrasive spray head, which is used to spray abrasive liquid and / or pure water;

[0012] The controller is used to control the grinding machine to be in an idle state or to grind a test wafer, spray pure water onto the grinding pad by the abrasive nozzle for cleaning, grind the grinding pad by the grinding dressing disk to maintain its roughness, and grind the metal ion replenishing structure to generate metal ions at the same time.

[0013] Preferably, the material of the metal structure is copper.

[0014] Preferably, the substrate is made of stainless steel.

[0015] Preferably, the material of the isolation layer includes at least one of chromium, nickel, and nickel-palladium alloy.

[0016] Preferably, the material of the abrasive particles is diamond.

[0017] Preferably, the method for forming the metal ion supplement structure comprises: forming a metal layer on the isolation layer, wherein the material of the metal layer is the same as that of the metal structure.

[0018] Preferably, the method for forming the metal ion supplement structure comprises: replacing a portion of the abrasive particles with a material that is the same as that of the metal structure.

[0019] As described above, the grinding device of the present invention has the following beneficial effects:

[0020] The present invention ensures that when the machine is in an idle state and during the process of grinding test wafers, new metal ions (such as copper ions) are always generated on the grinding and dressing disk, and the overall environment remains consistent and is not affected by water and grinding liquid cleaning, so that the chemical reaction is always in a stable state, and the product wafer always maintains a high and stable grinding rate during the grinding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Shown is a schematic structural diagram of the grinding device of the present invention;

[0022] Figure 2 Shown is a schematic diagram of the structure of a grinding and dressing disc of the present invention;

[0023] Figure 3 Shown is a schematic diagram of another grinding and dressing disc structure of the present invention;

[0024] Figure 4 It is a schematic diagram showing the comparison of Cu CMP grabbing endpoint time of the present invention and the prior art. DETAILED DESCRIPTION

[0025] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0026] See also Figure 1 The present invention provides a grinding device, comprising:

[0027] A grinding pad 102 and a grinding table 101, wherein the grinding pad 102 is placed on the grinding table 101, and the grinding table 101 drives the grinding pad 102 to rotate synchronously;

[0028] The wafer 104 to be processed needs to be ground for metal structure;

[0029] A wafer fixing device 103, which is used to fix the wafer to be processed 104;

[0030] The grinding and dressing disc 106 includes a substrate 1061, on which an isolation layer 1062 and protruding abrasive particles 1064 are arranged. The isolation layer 1062 is arranged on the surface of the substrate 1061 to prevent the substrate 1061 from contaminating the grinding pad 102 during grinding. The abrasive particles 1064 are partially embedded in the isolation layer 1062, and the isolation layer 1062 also plays a role in fixing the abrasive particles 1064. A metal ion supplement structure made of the same material as the metal structure is also formed on the substrate 1061, which is used to grind the grinding pad 102 to maintain its roughness when the grinding machine is in an idle state or grinding a test wafer, and to grind the metal ion supplement structure to generate metal ions at the same time;

[0031] In an embodiment of the present invention, the material of the metal structure is copper. The metal structure is a portion of the back-end metal interconnect structure that includes copper, and the interconnect structure includes various conductive components to connect various IC devices to the integrated circuit. For example, the interconnect structure includes contacts; metal lines; and through holes.

[0032] In an embodiment of the present invention, the material of the substrate 1061 is stainless steel.

[0033] In an embodiment of the present invention, the material of the isolation layer 1062 includes at least one of chromium, nickel, and nickel-palladium alloy.

[0034] In an embodiment of the present invention, the material of the abrasive particles 1064 is diamond.

[0035] In the embodiments of the present invention, please refer to Figure 2The method for forming the metal ion supplement structure includes: forming a metal layer 1063 on the isolation layer 1062, wherein the material of the metal layer 1063 is the same as that of the metal structure. For example, a copper layer may be formed on the isolation layer 1062.

[0036] In the embodiments of the present invention, please refer to Figure 3 The method for forming the metal ion supplement structure includes: replacing the material of part of the abrasive particles 1064 with the same material as the metal structure to form replacement abrasive particles 1065. For example, the material of part of the abrasive particles 1064 can be replaced with copper material.

[0037] An abrasive spray head 105, which is used to spray abrasive liquid and / or pure water;

[0038] The controller is used to control the grinding machine to be in an idle state or to grind a test wafer, spray pure water onto the grinding pad 102 for cleaning by using the abrasive nozzle 105, grind the grinding pad 102 by using the grinding dressing disc 106 to maintain its roughness, and grind the metal ion replenishment structure to produce metal ions at the same time, so as to ensure that new metal ions (such as copper ions) are always produced on the grinding dressing disc 106 when the machine is in an idle state and during the grinding of the test wafer, and the overall environment remains consistent and is not affected by water and grinding liquid cleaning, so that the chemical reaction is always in a stable state, and the product wafer always maintains a high and stable grinding rate during the grinding process.

[0039] The controller may include:

[0040] Memory, used to store computer programs;

[0041] The processor is used to implement the steps of the above-mentioned mobile application debugging method when executing the program stored in the memory.

[0042] In addition, the electronic device may further include a communication bus and / or a communication interface, and the processor, the communication interface, and the memory communicate with each other via the communication bus. The communication bus mentioned in the electronic device may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The communication bus may be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus.

[0043] The communication interface is used for communication between the above electronic device and other devices.

[0044] The memory may include a random access memory (RAM) or a non-volatile memory (NVM), such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the aforementioned processor.

[0045] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0046] In another embodiment provided in the present application, a computer-readable storage medium is provided, in which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above-mentioned debugging methods for mobile applications are implemented.

[0047] In another embodiment provided by the present application, a computer program product including instructions is also provided, which, when executed on a computer, enables the computer to execute any mobile application debugging method of the above embodiments.

[0048] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium, (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a solid-state hard disk Solid State Disk (SSD), etc.

[0049] Please refer to 4. By comparing the difference in the end point time of the copper layer grinding of the product sheet in the environment containing copper ions and without copper ions after the machine is idle, it can be seen that the grinding rate in the environment containing copper ions is higher and very stable, which is conducive to the precise control of the product film thickness and is of great help to the stable delivery of the product.

[0050] It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner. Therefore, the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0051] In summary, the present invention ensures that when the machine is in an idle state and during the grinding test wafer, new metal ions (such as copper ions) are always generated on the grinding and dressing disk, and the overall environment remains consistent and is not affected by water and grinding liquid cleaning, so that the chemical reaction is always in a stable state, and the product wafer always maintains a high and stable grinding rate during the grinding process. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has a high industrial utilization value.

[0052] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A grinding device, characterized in that: include: A grinding pad and a grinding table, wherein the grinding pad is placed on the grinding table, and the grinding table drives the grinding pad to rotate synchronously; A wafer to be processed, wherein the wafer to be processed needs to be ground with a metal structure; A wafer fixing device, used for fixing the wafer to be processed; A grinding and dressing disc, the grinding and dressing disc comprising a substrate, an isolation layer and protruding grinding particles are arranged on the substrate, and a metal ion supplement structure made of the same material as the metal structure is formed on the substrate, which is used for grinding the grinding pad to maintain its roughness and grinding the metal ion supplement structure to generate metal ions when the grinding machine is in an idle state or grinding a test wafer; An abrasive spray head, which is used to spray abrasive liquid and / or pure water; The controller is used to control the grinding machine to be in an idle state or to grind a test wafer, spray pure water onto the grinding pad by the abrasive nozzle for cleaning, grind the grinding pad by the grinding dressing disk to maintain its roughness, and grind the metal ion replenishing structure to generate metal ions at the same time.

2. The grinding device according to claim 1, characterized in that: The material of the metal structure is copper.

3. The grinding device according to claim 1, characterized in that: The material of the substrate is stainless steel.

4. The grinding device according to claim 1, characterized in that: The material of the isolation layer includes at least one of chromium, nickel, and nickel-palladium alloy.

5. The grinding device according to claim 1, characterized in that: The material of the abrasive particles is diamond.

6. The grinding device according to claim 1, characterized in that: The method for forming the metal ion supplement structure includes: forming a metal layer on the isolation layer, wherein the material of the metal layer is the same as that of the metal structure.

7. The grinding device according to claim 1, characterized in that: The method for forming the metal ion supplement structure includes: replacing a portion of the abrasive particles with a material that is the same as the metal structure.

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