Negative pressure adsorption disc structure for semiconductor processing

Abstract

The utility model provides a kind of negative pressure adsorption disc structure for semiconductor processing, including chuck, base and fixed seat.The upper surface of chuck is equipped with the support area higher than adsorption area, adsorption area is lower than support area and is used to form negative pressure adsorption wafer;Base middle part is equipped with through-hole and umbrella-shaped airflow cavity, fixed seat lower end is communicated with the air passage of through-hole by thread connection.The adsorption area includes circular central adsorption area and annular circumferential adsorption area concentric with it, and support area is also concentric annular, and it is distributed with circumferential adsorption area in radial equidistant interval.Chuck is equipped with the air path of through communication airflow cavity, adsorption area is equipped with the vacuum suction hole of mi type distribution, improve airflow uniformity and adsorption response speed.Base and fixed seat are equipped with locating bolt hole, realize accurate alignment and reliable connection.The structure is designed by partition adsorption and support, so that wafer is uniformly stressed, effectively prevent warping, slip and surface damage.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor processing technology, and in particular to a negative pressure adsorption disk structure for semiconductor processing. Background Technology

[0002] In semiconductor manufacturing, wafers require high-precision processing in various equipment such as etching, deposition, cleaning, and photolithography. The stable and flat fixing method directly affects processing quality and product yield. Traditional mechanical clamping methods often fix wafers by clamping them at the edges, which can easily cause surface scratches, stress concentration, or localized deformation, making it particularly difficult to meet the processing requirements of large-size, ultra-thin wafers. In recent years, negative pressure adsorption technology has been widely used for wafer support due to its advantages such as non-contact and uniform force distribution. However, existing adsorption pad structures generally suffer from uneven adsorption force distribution, airflow turbulence leading to vibration, and insufficient multi-region adsorption control, making it difficult to balance adsorption stability at the wafer center and edges. Utility Model Content

[0003] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide a negative pressure adsorption disk structure for semiconductor processing, which solves the problems of uneven adsorption force distribution and turbulent airflow in the prior art.

[0004] To achieve the above and other related objectives, this utility model provides the following technical solution:

[0005] A negative pressure adsorption disk structure for semiconductor processing includes: a suction cup, the upper surface of which has a support area for supporting a wafer and an adsorption area below the support area for adsorbing the wafer; a base disposed at the lower end of the suction cup, the middle of which has a through hole and an airflow cavity; and a fixing seat disposed at the lower end of the base, the fixing seat being threadedly connected along the axial direction to an air passage communicating with the through hole.

[0006] To achieve the above technical solution, when wafers need to be adsorbed for semiconductor processing, an external vacuum pump is connected to the through-hole and airflow chamber in the center of the base via a ventilation pipe. After the vacuum pump is started, it extracts air from the airflow chamber, creating a negative pressure environment in the airflow chamber and the adsorption area of ​​the suction cup connected to it. Because the adsorption area is lower than the support area, and the wafer is placed on the support area and covers the adsorption area, the air pressure below the wafer is lower than the external atmospheric pressure. Under the action of this pressure difference, the wafer is firmly adsorbed onto the adsorption area of ​​the suction cup, thus achieving stable fixation of the wafer for subsequent semiconductor processing operations. After processing is completed, the vacuum pump is turned off, and external air enters through the ventilation pipe, restoring the air pressure in the adsorption area to the same level as the outside air, allowing the wafer to be easily removed. By setting an adsorption area lower than the support area to create negative pressure adsorption, compared to some traditional clamping methods, direct contact and mechanical damage to the wafer surface are avoided, better protecting the wafer's integrity during processing. This is especially suitable for semiconductor processing with extremely high surface quality requirements, helping to improve product yield. On the other hand, the base, mounting base and ventilation pipe are connected by threads, which facilitates installation, disassembly and maintenance. When the equipment needs to be repaired or parts replaced, the adsorption plate structure can be operated quickly, reducing the downtime and maintenance costs of the equipment.

[0007] In one embodiment of the present invention, the suction cup is provided with a plurality of air passages that are uniformly arranged and connected to the airflow cavity, and the adsorption area is provided with a plurality of vacuum suction holes that are connected to the air passages.

[0008] The above technical solution achieves a more uniform distribution of numerous vacuum suction holes in the adsorption area, resulting in a more uniform adsorption force on various parts of the wafer. This effectively avoids wafer warping and deformation caused by uneven local adsorption forces. Especially for ultra-thin wafers or wafers with extremely high flatness requirements, it can greatly improve the product yield and meet the high precision requirements of semiconductor processing.

[0009] In one embodiment of this utility model, the supporting region and the adsorption region are arranged at intervals.

[0010] To achieve the above technical solution, the support region and the adsorption region are spaced apart and operate independently. During the adsorption process, the support region only serves to support the wafer, while the adsorption region creates a negative pressure environment through the gas path connected to the gas flow cavity and the vacuum suction holes on the adsorption region. When the wafer is placed on the support region, the adsorption region below it generates an upward adsorption force due to the negative pressure. This adsorption force passes through the spacer region and acts on the wafer. Utilizing the pressure difference between the upper and lower surfaces of the wafer, the wafer is firmly adsorbed above the support region, achieving stable fixation of the wafer and thus meeting the wafer positioning accuracy requirements during semiconductor processing.

[0011] In one embodiment of the present invention, the adsorption region includes a central adsorption region and a peripheral adsorption region.

[0012] To achieve the above technical solution, after the wafer is placed on the upper surface of the chuck, the lower center corresponds to the central adsorption area, and the lower edge corresponds to the peripheral adsorption area. The two areas work together to achieve uniform adsorption of the entire wafer. This partitioned design allows for adjustment of the suction force distribution in different areas according to process requirements, ensuring that the wafer remains flat and stable during high-speed rotation or precision machining, and avoiding warping or slippage caused by local stress concentration.

[0013] In one embodiment of this utility model, the central adsorption region is circular, and the peripheral adsorption region and the supporting region are arranged in a ring concentrically with the central adsorption region.

[0014] To achieve the above technical solution, the negative pressure adsorption disk structure features a circular central adsorption area, while the peripheral adsorption areas and support areas are concentric annular structures. During operation, the vacuum system draws air from the airflow chamber of the base into both the circular central adsorption area and the annular peripheral adsorption areas, creating a continuous and rationally distributed negative pressure field. When the wafer is placed on the chuck, its geometric center corresponds to the circular central adsorption area, the edge area corresponds to the annular peripheral adsorption area, and the annular support area is located outside or between the peripheral adsorption areas, providing stable support. This concentric layout ensures that the adsorption force is uniformly and symmetrically distributed along the wafer's radial direction, effectively preventing eccentricity, warping, or slippage caused by uneven force distribution.

[0015] In one embodiment of this utility model, the peripheral adsorption region and the support region are equidistantly distributed in the radial direction.

[0016] To achieve the above technical solution, in this negative pressure adsorption disk structure, the peripheral adsorption area and the support area are equidistantly distributed radially, meaning that along the wafer radius, the adsorption and support units are arranged alternately with uniform spacing. This regular layout ensures that the force on the wafer edge area is highly symmetrical and evenly distributed radially, effectively suppressing vibration, displacement, or deformation during processing.

[0017] In one embodiment of this utility model, the vacuum suction holes are distributed in a star-shaped pattern on the suction cup.

[0018] To achieve the above technical solution, the vacuum suction holes on the suction cup surface are distributed in a star pattern, that is, they are evenly arranged along multiple radial and diagonal directions. When the vacuum system pumps air into the adsorption area through the through holes and airflow chamber of the base, the star-shaped vacuum suction holes can effectively connect the central adsorption area with the peripheral adsorption area, forming a multi-path, fast-response negative pressure conduction channel.

[0019] In one embodiment of this utility model, the airflow cavity is umbrella-shaped.

[0020] To achieve the above technical solution, the airflow cavity has an umbrella-shaped structure, located in the center of the base. Its shape gradually expands from bottom to top, covering the adsorption area below the suction cup. Guided by the umbrella-shaped cavity, the airflow converges from the inclined inner wall towards the center and flows downwards, finally exiting through the ventilation pipe. This structure effectively reduces local airflow blockage or turbulence, thereby quickly forming a stable and consistent negative pressure environment across the entire adsorption surface of the suction cup.

[0021] In one embodiment of this utility model, positioning screw holes are provided on both the base and the fixing seat.

[0022] To achieve the above technical solution, positioning screw holes are provided on both the base and the fixed seat. During assembly, the bolts are inserted into the positioning screw holes and tightened to achieve precise alignment and rigid connection between the base and the fixed seat.

[0023] As described above, the negative pressure adsorption disk structure for semiconductor processing of this utility model has the following beneficial effects: The negative pressure adsorption disk structure provided by this utility model, by setting an adsorption area lower than the support area and combining a central and peripheral partitioned adsorption design, achieves uniform and stable adsorption of the wafer under atmospheric pressure difference, effectively avoiding mechanical damage and improving surface protection and processing yield. The cross-shaped vacuum suction holes on the suction disk and the umbrella-shaped airflow cavity on the base work together to optimize the airflow path, improve pumping efficiency and pressure distribution uniformity, and ensure rapid response and consistent adsorption. The concentric ring layout and radially equidistant adsorption and support areas further enhance the force symmetry and suppress warping and slippage. Attached Figure Description

[0024] Figure 1 The diagram shown is a structural schematic of this utility model.

[0025] Figure 2 The diagram shows the structure of the suction cup.

[0026] Figure 3 The diagram shown is a structural schematic of the base.

[0027] Component designation explanation

[0028] 1. Suction cup; 11. Support area; 12. Adsorption area; 2. Base; 21. Through hole; 22. Airflow chamber; 3. Fixing base; 4. Air passage; 13. Air path; 14. Vacuum suction hole; 121. Central adsorption area; 122. Peripheral adsorption area; 5. Positioning screw hole. Detailed Implementation

[0029] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. It should be noted that, unless otherwise specified, the following embodiments and features can be combined with each other.

[0030] Please see Figures 1 to 3 This utility model provides a negative pressure adsorption disk structure for semiconductor processing, including: a suction cup 1, the upper surface of which has a support area 11 for supporting a wafer and an adsorption area 12 lower than the support area 11 for adsorbing the wafer; a base 2 disposed at the lower end of the suction cup 1, the middle part of which has a through hole 21 and an airflow cavity 22; and a fixing seat 3 disposed at the lower end of the base 2, the fixing seat 3 being threaded along the axial direction with an air passage 4 communicating with the through hole 21.

[0031] When a wafer needs to be adsorbed for semiconductor processing, an external vacuum pump is connected to the through-hole 21 and airflow chamber 22 in the middle of the base 2 through the ventilation pipe 4. After the vacuum pump is started, the air in the airflow chamber 22 is extracted, creating a negative pressure environment in the airflow chamber 22 and the adsorption area 12 of the suction cup 1 connected to it. Since the adsorption area 12 is lower than the support area 11, and the wafer is placed on the support area 11 and covers the adsorption area 12, the air pressure below the wafer is lower than the external atmospheric pressure. Under the action of the atmospheric pressure difference, the wafer is firmly adsorbed on the adsorption area 12 of the suction cup 1, thereby achieving stable fixation of the wafer for subsequent semiconductor processing operations. After processing is completed, the vacuum pump is turned off, and external air enters through the ventilation pipe 4, restoring the air pressure in the adsorption area 12 to the same level as the outside air, allowing the wafer to be easily removed. By setting an adsorption area 12 lower than the support area 11 to form a negative pressure adsorption, compared with some traditional clamping methods, direct contact and mechanical damage to the wafer surface are avoided, which can better protect the integrity of the wafer during processing. It is especially suitable for semiconductor processing with extremely high surface quality requirements and helps to improve product yield. On the other hand, the base 2, the fixing seat 3 and the ventilation pipe 4 are connected by threads, which facilitates installation, disassembly and maintenance. When the equipment needs to be repaired or parts replaced, the adsorption plate structure can be operated quickly, reducing equipment downtime and maintenance costs.

[0032] The suction cup 1 has a plurality of air passages 13 that are uniformly formed and connected to the airflow cavity 22. The adsorption area 12 has a plurality of vacuum suction holes 14 that are connected to the air passages 13. The numerous vacuum suction holes 14 are evenly distributed in the adsorption area 12, which makes the adsorption force on various parts under the wafer more uniform. This effectively avoids the wafer warping and deformation caused by uneven local adsorption force. Especially for some ultra-thin wafers or wafers with extremely high flatness requirements, it can greatly improve the product yield and meet the high precision requirements of semiconductor processing.

[0033] The support region 11 and the adsorption region 12 are spaced apart. Because the support region 11 and the adsorption region 12 are spaced apart and independent of each other, during the adsorption process, the support region 11 only serves to support the wafer, while the adsorption region 12 forms a negative pressure environment through the gas path 13 connected to the airflow cavity 22 and the vacuum suction hole 14 on the adsorption region 12. When the wafer is placed on the support region 11, the adsorption region 12 below it generates an upward adsorption force due to the negative pressure. This adsorption force acts on the wafer through the spaced area, utilizing the pressure difference between the upper and lower surfaces of the wafer to firmly adsorb it above the support region 11, achieving stable fixation of the wafer and thus meeting the requirements for wafer positional accuracy during semiconductor processing.

[0034] The adsorption region 12 includes a central adsorption region 121 and a peripheral adsorption region 122. After the wafer is placed on the upper surface of the chuck 1, the central adsorption region 121 corresponds to the lower part of the wafer, and the peripheral adsorption region 122 corresponds to the lower part of the wafer. The two regions work together to achieve uniform adsorption of the entire wafer. This partitioned design allows for adjustment of the suction distribution in different regions according to process requirements, ensuring that the wafer remains flat and stable during high-speed rotation or precision machining, and avoiding warping or slippage caused by local stress concentration.

[0035] The central adsorption region 121 is circular, while the peripheral adsorption region 122 and the support region 11 form a ring concentrically arranged with the central adsorption region 121. In this negative pressure adsorption disk structure, the central adsorption region 121 is designed to be circular, while the peripheral adsorption region 122 and the support region 11 are concentric ring structures. During operation, the vacuum system draws air into the circular central adsorption region 121 and the annular peripheral adsorption region 122 through the airflow cavity 22 of the base 2, forming a continuous and reasonably distributed negative pressure field. When the wafer is placed on the suction cup 1, its geometric center corresponds to the circular central adsorption region, the edge region corresponds to the annular peripheral adsorption region, and the annular support region 11 is located outside or between the peripheral adsorption regions, providing stable support. The concentric layout ensures that the adsorption force is uniformly and symmetrically distributed along the radial direction of the wafer, effectively avoiding eccentricity, warping, or slippage caused by uneven force.

[0036] The peripheral adsorption region 122 and the support region 11 are equidistantly distributed radially. In this negative pressure adsorption disk structure, the equidistant distribution of the peripheral adsorption region 122 and the support region 11 in the radial direction means that the adsorption and support units are arranged alternately with uniform spacing along the wafer radius. This regular layout ensures that the force on the wafer edge region is highly symmetrical and evenly distributed radially, effectively suppressing vibration, displacement, or deformation during processing.

[0037] The vacuum suction holes 14 are distributed in a star-shaped pattern on the suction cup 1. On the surface of the suction cup 1, the vacuum suction holes 14 are distributed in a star-shaped pattern, that is, they are evenly arranged along multiple radial and diagonal directions. When the vacuum system evacuates the adsorption area 12 through the through hole 21 and the airflow cavity 22 of the base 2, the star-shaped vacuum suction holes 14 can effectively connect the central adsorption area 121 with the peripheral adsorption areas 122, forming a multi-path, fast-response negative pressure conduction channel.

[0038] The airflow cavity 22 is umbrella-shaped. Located in the center of the base 2, the airflow cavity 22 gradually expands in diameter from bottom to top, covering the adsorption area 12 at the bottom of the suction cup 1. Guided by the umbrella-shaped cavity, the airflow converges from the inclined inner wall towards the center and flows downwards, finally exiting through the ventilation pipe 4. This structure effectively reduces local airflow blockage or turbulence, thereby quickly forming a stable and consistent negative pressure environment across the entire adsorption surface of the suction cup 1.

[0039] Both the base 2 and the fixed seat 3 have corresponding positioning screw holes 5. During assembly, the precise alignment and rigid connection between the base 2 and the fixed seat 3 are achieved by inserting bolts into the positioning screw holes 5 and tightening them.

[0040] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit this utility model. All equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A negative pressure adsorption disk structure for semiconductor processing, characterized in that, include: The suction cup (1) has a support area (11) for supporting the wafer and an adsorption area (12) below the support area (11) for adsorbing the wafer on its upper surface. The base (2) is located at the lower end of the suction cup (1), and the middle part of the base (2) is provided with a through hole (21) and an airflow cavity (22); A fixing seat (3) is provided at the lower end of the base (2), and the fixing seat (3) is threaded along the axial direction with a ventilation pipe (4) communicating with the through hole (21); The suction cup (1) is provided with a number of air passages (13) that are uniformly arranged and connected to the airflow cavity (22), and the adsorption area (12) is provided with a number of vacuum suction holes (14) that are connected to the air passages (13). The supporting region (11) and the adsorption region (12) are arranged at intervals; The adsorption region (12) includes a central adsorption region (121) and a peripheral adsorption region (122); The central adsorption region (121) is circular, and the peripheral adsorption region (122) and the support region (11) are arranged in a ring concentric with the central adsorption region (121). The peripheral adsorption region (122) and the support region (11) are equidistantly distributed in the radial direction; The vacuum suction holes (14) are distributed in a star-shaped pattern on the suction cup (1); The airflow cavity (22) is umbrella-shaped.

2. The negative pressure adsorption disk structure for semiconductor processing according to claim 1, characterized in that: Both the base (2) and the fixing seat (3) are provided with positioning screw holes (5).

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