Semiconductor chemical mechanical polishing chuck

Abstract

This utility model discloses a semiconductor chemical mechanical polishing (CMP) fixture for collaborative processing of multiple substrates with adjustable counterweights, relating to the field of semiconductor manufacturing equipment technology. The fixture comprises an array of substrate support units, a fixed counterweight system, and an adjustable counterweight system. The substrate support units utilize water adsorption and positioning groove technology to achieve synchronous and precise fixation and collaborative operation of multiple substrates. The fixed counterweight system connects the multi-substrate support adsorption units and the counterweight adjustment system. The adjustable counterweight system adopts a modular, detachable counterweight design, allowing for rapid adaptation to the pressure conditions required by semiconductor substrates of different sizes, thicknesses, and materials during the CMP process by increasing or decreasing the number of counterweights. This fixture significantly improves CMP efficiency and process adaptability, balancing the high efficiency of multi-substrate collaborative processing with the flexibility of counterweight adjustment, and has broad application value in the semiconductor manufacturing field.

Description

Technical Field

[0001] This utility model belongs to the field of semiconductor manufacturing equipment technology, specifically relating to a semiconductor chemical mechanical polishing (CMP) fixture, and more particularly to a semiconductor chemical mechanical polishing fixture that can achieve collaborative processing of multiple substrates and has adjustable weight. Background Technology

[0002] In the semiconductor manufacturing field, CMP (Chemical Motion Processing) is a crucial step in achieving global planarization of the substrate surface, and its processing efficiency and quality directly determine the performance and production benefits of semiconductor devices. However, traditional semiconductor CMP fixtures employ a single-substrate processing mode, meaning that only one substrate can be fixed and polished at a time, and the counterweight is not adjustable. This approach has the following drawbacks:

[0003] 1. Limitation on capacity expansion: Single-piece processing leads to frequent equipment start-ups and shutdowns, repetitive operations, extended processing cycles, reduced production efficiency, and difficulty in meeting the demands of large-scale, batch production;

[0004] 2. Increased production costs: During single-piece processing, the idling and waiting time of the equipment results in a waste of energy and resources;

[0005] 3. Non-adjustable pressure: Different substrate sizes require significantly different pressure conditions during polishing, and existing CMP fixtures typically have fixed counterweight systems that cannot be flexibly adjusted based on substrate size, thickness, and material. This makes it difficult for the same fixture to adapt to different process requirements. When processing diverse substrates, either insufficient counterweight results in inadequate polishing pressure, failing to achieve the desired planarization effect; or excessive counterweight damages the substrate, severely impacting product yield.

[0006] Therefore, developing a novel CMP fixture with multi-substrate collaborative processing capability and dynamically adjustable counterweight is of great significance for breaking through existing process bottlenecks and improving semiconductor manufacturing efficiency and product quality. Utility Model Content

[0007] The main objective of this invention is to provide a semiconductor CMP fixture with adjustable weight for collaborative processing of multiple substrates, addressing the shortcomings of traditional fixtures in terms of efficiency, cost, and quality. This invention, through innovative structural design, achieves CMP processing with adjustable weight for collaborative processing of multiple substrates, thereby overcoming existing process bottlenecks and improving semiconductor manufacturing efficiency and product quality.

[0008] This utility model is achieved through the following technical solution:

[0009] The semiconductor CMP fixture with adjustable counterweight and multi-substrate collaborative processing described in this utility model mainly consists of three parts: an array of substrate support units for adsorption, a fixed counterweight system, and an adjustable counterweight system, wherein:

[0010] The substrate carrier unit's adsorption body is circular, made of PVDF or PEEK, and contains multiple substrate carrier units arranged in an array. Each substrate carrier unit integrates a water adsorption structure and positioning grooves. The water adsorption structure utilizes the capillary adsorption force of the water film to tightly adsorb the substrate onto the carrier unit surface. The positioning grooves are precisely designed according to the substrate's edge contour, enabling precise fitting with the substrate edge and thus accurately defining the substrate's position. Through the synergistic effect of the water adsorption structure and positioning grooves, multiple substrates can be synchronously and precisely fixed on the same fixture, ensuring that multiple substrates can work collaboratively during the CMP process, effectively improving polishing efficiency and processing quality. Simultaneously, the design of axial and radial drainage grooves allows the CMP solution to fully contact the surface of the substrate to be treated, resulting in more efficient and uniform substrate surface treatment.

[0011] Fixed counterweight system: Serving as a connecting hub, one end is connected to the multi-substrate adsorption unit via threads for a high-precision and stable connection, while the other end connects to the adjustable counterweight system via connecting posts. This system is constructed from corrosion-resistant, high-strength stainless steel, possessing excellent structural strength and stability. It ensures the normal operation of the substrate-supporting adsorption unit while providing a reliable installation and support foundation for the adjustable counterweight system, ensuring the entire fixture maintains structural integrity and stability during operation.

[0012] Adjustable counterweight system: The adjustable counterweight system adopts an innovative design with modular and detachable counterweight blocks. Each counterweight block is designed with a standard connection port, which allows for quick connection and disassembly with the fixed counterweight system. The number of counterweight blocks can be flexibly selected to increase or decrease according to the size, thickness, and material characteristics of the substrate to be polished, combined with the specific pressure requirements of the CMP process. In this way, the overall counterweight of the fixture can be quickly adjusted, thereby accurately adapting to the pressure conditions required during the polishing process of different substrate sizes, significantly improving the fixture's adaptability to diverse process requirements.

[0013] This utility model has the following advantages and effects:

[0014] (1) High-efficiency collaborative processing: The substrate carrier adsorption body uses water adsorption and positioning groove positioning technology to achieve synchronous and precise fixation of multiple substrates, ensuring that multiple substrates can work together during the polishing process. Compared with traditional fixtures, it effectively reduces the time loss of processing a single substrate one by one, greatly improves polishing efficiency, and meets the needs of large-scale production.

[0015] (2) Flexible and precise counterweight: The modular and detachable counterweight design of the adjustable counterweight system, combined with counterweights of different weight specifications, enables rapid and precise adjustment of the fixture counterweight. It can flexibly adapt to the pressure conditions required by semiconductor substrates of different sizes, thicknesses and materials during chemical mechanical polishing, significantly improving the process adaptability of the fixture and broadening its application range.

[0016] (3) Stable and reliable structure: The fixed counterweight system is made of high-strength materials and has a solid connection, which provides reliable support for the substrate carrier unit adsorption body and the adjustable counterweight system, ensuring the stability of the entire fixture during operation, reducing substrate processing quality problems caused by fixture instability, and improving product yield.

[0017] (4) Easy and practical operation: The modular design of the adjustable counterweight system makes it easy to add or remove counterweights, improving the convenience and efficiency of production operations. Attached Figure Description

[0018] Figure 1 This is an exploded axial view of the semiconductor CMP fixture of this utility model.

[0019] Figure 2 This is an axonometric view of the substrate support unit adsorption body 2 of this utility model.

[0020] Figure 3 This is a three-axis side view of the fixed counterweight system of this utility model.

[0021] Figure 4 This is an isometric view of the four-unit module of the adjustable counterweight system of this utility model.

[0022] In the figure: 1. Substrate; 2. Substrate support unit adsorption body; 2-1. External thread; 2-2. Substrate positioning groove; 2-3. Wafer removal point; 2-4. Axial flow channel; 2-5. Radial flow channel; 2-6. Guide channel; 3. Fixed counterweight system; 3-1. Internal thread; 3-2. Connecting post; 4. Adjustable counterweight system; 4-1. Connection port. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0024] like Figure 1As shown, the semiconductor CMP fixture of this utility model includes a substrate support unit adsorption body 2, a fixed counterweight system 3, and an adjustable counterweight system 4 connected sequentially from bottom to top.

[0025] The substrate support unit adsorption body 2 is cylindrical in shape, with four substrate positioning grooves 2-2 symmetrically arranged at its lower center. Around the substrate positioning grooves 2-2 are three circular axial drainage grooves 2-4, four radial drainage grooves 2-5 at 90° angles to each other, and a guide groove 2-6 to facilitate communication between the four substrate positioning grooves 2-2 at their closest points. The upper part of the substrate support unit adsorption body 2 has an external thread 2-1. After the substrate 1 is processed, at the four substrate positioning grooves 2-2 near the axial drainage grooves 2-4 (see... Figure 2 (2-3) Take out the substrate 1 from the wafer removal point.

[0026] The fixed counterweight system 3 is cylindrical in shape. Its lower part is provided with an internal thread 3-1 that is threaded to the external thread 2-1 of the substrate support unit adsorption body 2. Its upper center is provided with a cube-shaped connecting post 3-2 that is connected to the adjustable counterweight system 4.

[0027] The adjustable counterweight system 4 is in the shape of a disc, with the same radius as the fixed counterweight system 3. At its center is a connection port 4-1 that connects and cooperates with the connecting post 3-2 of the fixed counterweight system 3. When connecting, the connecting post 3-2 is embedded into the connection port 4-1.

[0028] The adjustable counterweight system 4 can be several modules with the same radius but different weights. The weight of a single module can be 500g, 400g, 300g, 200g, or 100g. The counterweight can be adjusted by adding or subtracting the number of modules and by adjusting the combination of modules.

[0029] The height of the connecting column 3-2 is not less than the sum of the heights of the modules of several adjustable counterweight systems 4. Example 1

[0030] The substrate 1 is positioned and adsorbed by the positioning groove 2-2 on the substrate support unit adsorption body 2. The fixed counterweight system 3 is located above the substrate support unit adsorption body 2 and is connected to the substrate support unit adsorption body 2 by threads. The adjustable counterweight system 4 is connected to the fixed counterweight system 3 by connecting post 3-2, and plays the role of adjusting the counterweight. The dimensions of the substrate support unit adsorption body 2, the fixed counterweight system 3, and the adjustable counterweight system 4 can be designed according to the actual situation. This embodiment takes four 30×30mm substrates as an example.

[0031] (1) The substrate support unit adsorption body 2 is made of PEEK with an outer diameter of 100 mm and a fine external thread 2-1 of M100×0.5 mm, which can ensure high precision and high coaxiality fit with the fixed counterweight system 3. The surface roughness Ra of the adsorption surface of the substrate positioning groove 2-2 of the substrate support unit adsorption body 2 is ≤0.4 μm and the contact angle is >120°. The shape and size of the substrate positioning groove 2-2 are determined according to the size of the substrate 1 to ensure that the semiconductor substrate can be stably adsorbed in the positioning groove. The depth of the substrate positioning groove 2-2 is 1 / 3 of the substrate thickness to ensure that the substrate does not move during the CMP process. After the substrate 1 is processed, the substrate 1 is taken out near the axial drainage groove 2-4 of the four substrate positioning grooves 2-2. The design of the three axial drainage grooves 2-4, the four evenly distributed radial drainage grooves 2-5, and the guide grooves 2-6 that connect the positioning grooves 2-2 can make the CMP solution fully contact the surface of the substrate to be treated, making the substrate surface treatment more efficient and uniform. The depth of the axial flow channel 2-4 and the four evenly distributed radial flow channels 2-5 is 2 to 3 times the thickness of the semiconductor substrate, and the depth of the flow channel 2-6 is consistent with that of the positioning channel 2-2.

[0032] (2) The fixed counterweight system 3 is made of corrosion-resistant high-strength stainless steel because the CMP solution contains corrosive solutions such as oxidants, acids, and alkalis. The fixed counterweight system 3 has an inner diameter of 100 mm and a fine-pitch internal thread 3-1 of M100×0.5 mm, which ensures a high-precision and high-coaxial fit with the substrate support unit adsorption body 2. The adjustable counterweight system 4 is connected to the fixed counterweight system 3 through the connecting post 3-2.

[0033] (3) The adjustable counterweight system 4 is made of high-strength stainless steel and is connected to the connecting column 3-2 of the fixed counterweight system 3 through the connecting port 4-1. The weight of a single adjustable counterweight system 4 module is 500g, 400g, 300g, 200g, or 100g. The counterweight is adjusted by adding or subtracting the number of modules and by adjusting the combination of modules. Example 2

[0034] The polishing process using the semiconductor CMP fixture of this invention includes:

[0035] (1) Component assembly and connection: First, check whether the threads 2-1 and 3-1 of the substrate support unit adsorption body 2 and the fixed counterweight system 3 are intact, damaged or deformed. After the inspection, the substrate support unit adsorption body 2 with an outer diameter of 100mm and an M100×0.5 mm fine external thread 2-1 is tightly connected to the corrosion-resistant high-strength stainless steel fixed counterweight system 3 with an inner diameter of 100mm and an M100×0.5 mm fine internal thread 3-1, through thread engagement, to ensure that the two achieve high precision and high coaxiality fit.

[0036] (2) Substrate loading and positioning: Based on the actual dimensions of the semiconductor substrate 1, determine the shape and size of the substrate positioning groove 2-2 on the substrate carrier adsorption body 2. Utilizing the characteristics of the adsorption surface roughness Ra≤0.4 μm and contact angle>120° of the substrate positioning groove 2-2, place the four substrates 1 stably in the positioning grooves, ensuring that the depth of the positioning grooves is 1 / 3 of the substrate thickness, thereby achieving precise positioning and firm adsorption of the substrates and preventing displacement during the CMP process. When placing the semiconductor substrates 1, pay attention to the stability of the operation to avoid collisions that could damage the semiconductor substrates 1.

[0037] (3) Adjustable counterweight system configuration: According to the pressure required by the CMP process, the adjustable counterweight system 4 made of high-strength stainless steel is connected to the connecting column 3-2 of the fixed counterweight system 3 through the connection port 4-1. By increasing or decreasing the number of adjustable counterweight system 4 modules with individual weights of 500g, 400g, 300g, 200g and 100g and adjusting the combination of modules, the overall counterweight adjustment is completed, providing stable pressure for the entire CMP process.

[0038] (4) CMP solution treatment process: In the CMP processing stage, the equipment is started to make the substrate support unit run. The special structure of the axial flow groove 2-4 and radial flow groove 2-5 on the adsorption body of the substrate support unit is used to guide the CMP solution to uniformly and fully cover the surface of the substrate to be treated, so as to promote the efficient interaction between the substrate surface and the CMP solution and achieve uniform treatment.

[0039] (5) Substrate removal and cleaning: After the semiconductor substrate has completed the CMP process, the substrate is safely and conveniently removed by adsorbing the substrate on the main body 2 with the help of the substrate support unit at the four substrate positioning grooves 2-2 near the axial flow grooves 2-4. Then, the substrate surface is cleaned with ultrapure water, dried with nitrogen gun and placed in a special substrate culture dish to complete the entire semiconductor substrate CMP process.

[0040] (6) Post-polishing treatment: After the semiconductor substrate 1 is processed and removed, the fixture is cleaned. First, rinse off the residual polishing debris and moisture on the surface of the substrate support unit adsorption body 2 with clean water, and then wipe it dry with a clean soft cloth. During the cleaning process, care should be taken to protect the surface of the adsorption plate and avoid scraping it with sharp tools. The fixed counterweight system 3 and the adjustable counterweight system 4 are rinsed dry with ultrapure water and blown dry with a nitrogen gun. After all fixtures are cleaned, they are properly stored for future use.

[0041] Through the above specific implementation methods, the advantages of the semiconductor CMP fixture with multi-substrate collaborative processing and adjustable counterweight can be fully utilized, significantly improving polishing efficiency and process adaptability, while taking into account both the high efficiency of multi-substrate collaborative processing and the flexibility of counterweight adjustment.

[0042] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A semiconductor chemical mechanical polishing fixture, characterized in that: The fixture includes a substrate support unit adsorption body (2), a fixed counterweight system (3), and an adjustable counterweight system (4) connected sequentially from bottom to top. The substrate support unit adsorption body (2) is used for adsorption and positioning of multiple substrates. The fixed counterweight system (3) is used to connect the substrate support adsorption body (2) and the adjustable counterweight system (4). The adjustable counterweight system (4) is used to efficiently adjust the counterweight. The substrate support unit adsorption body (2) is cylindrical in shape, with four substrate positioning grooves (2-2) symmetrically arranged at the center of its lower part. A circular axial flow channel (2-4), four radial flow channels (2-5) at 90° to each other, and a flow channel (2-6) that enables the four substrate positioning grooves (2-2) to communicate with each other when they are close to each other are arranged around the substrate positioning grooves (2-2). The upper part of the substrate support unit adsorption body (2) is provided with an external thread (2-1). The fixed counterweight system (3) is cylindrical in shape. Its lower part is provided with an internal thread (3-1) that is threaded to the external thread (2-1) of the substrate support unit adsorption body (2). Its upper center is provided with a cube connecting post (3-2) that is connected to the adjustable counterweight system (4). The adjustable counterweight system (4) is in the shape of a disc, with the same radius as the fixed counterweight system (3), and a connection port (4-1) at its center that connects and cooperates with the connecting column (3-2) of the fixed counterweight system (3).

2. The semiconductor chemical mechanical polishing fixture according to claim 1, characterized in that: There are 2 to 4 axial drainage channels (2-4).

3. The semiconductor chemical mechanical polishing fixture according to claim 1, characterized in that: The adjustable counterweight system (4) consists of several modules with the same radius but different weights.

4. The semiconductor chemical mechanical polishing fixture according to claim 3, characterized in that: The weight of a single adjustable counterweight system (4) module is 500g, 400g, 300g, 200g, or 100g. The counterweight can be adjusted by adding or subtracting the number of modules and by adjusting the combination of modules.

5. The semiconductor chemical mechanical polishing fixture according to claim 4, characterized in that: The height of the connecting column (3-2) is not less than the sum of the heights of several adjustable counterweight system (4) modules.

6. The semiconductor chemical mechanical polishing fixture according to claim 1, characterized in that: After the substrate (1) is processed, the substrate (1) is removed from the four substrate positioning slots (2-2) near the axial drainage slots (2-4).

7. The semiconductor chemical mechanical polishing fixture according to claim 1, characterized in that, The surface roughness Ra of the adsorption surface of the substrate positioning groove (2-2) is ≤0.4μm, and the contact angle is >120°.

8. The semiconductor chemical mechanical polishing fixture according to claim 1, characterized in that: The depth of the substrate positioning groove (2-2) is 1 / 3 of the thickness of the substrate (1), which is used to ensure that the substrate does not move during the CMP process.

9. The semiconductor chemical mechanical polishing fixture according to claim 1, characterized in that: The depth of the axial flow channel (2-4) and the four evenly distributed radial flow channels (2-5) is 2 to 3 times the thickness of the substrate (1), and the depth of the flow channel (2-6) is consistent with that of the positioning channel (2-2).

10. The semiconductor chemical mechanical polishing fixture according to claim 1, characterized in that: The substrate carrier unit adsorption body (2) is made of PEEK.

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