Chemical mechanical planarization equipment

Abstract

The utility model provides chemical mechanical planarization equipment, and belongs to the technical field of semiconductor device manufacturing. The chemical mechanical planarization equipment comprises a front end unit, a cleaning unit, a polishing unit, a first transfer assembly arranged between the front end unit and the cleaning unit, a second transfer assembly arranged on the cleaning unit and a third transfer assembly arranged on the polishing unit which are sequentially arranged along a first linear path, the number of the cleaning units is equal to that of the polishing units, each polishing unit comprises a rotating frame, a plurality of polishing heads fixedly connected to the rotating frame and a plurality of polishing tables located below the polishing heads, and the polishing heads are evenly distributed on a rotating shaft of the rotating frame in a sleeving mode. The number of the polishing tables is one less than that of the polishing heads so as to form a loading and unloading position, the third transfer assembly is provided with a first working point position and a second working point position, and the first working point position is the loading and unloading position.

Description

Technical Field

[0001] The utility model belongs to the technical field of semiconductor device manufacturing, and in particular relates to a chemical mechanical planarization device. Background Art

[0002] Chemical mechanical planarization is a production process that uses a combination of chemical corrosion and mechanical force to planarize silicon wafers or their substrate materials. The planarized silicon wafer surface makes it easier to form patterns during dry etching, and the smooth silicon wafer surface also makes it possible to use smaller metal patterns, thereby improving integration.

[0003] In the existing chemical mechanized planarization process, when polishing silicon wafers, the silicon wafer is usually placed on a separate polishing table, and the polishing pad and the silicon wafer are pressed together by a movable polishing head. At the same time, corresponding chemical reagents are added to the processing surface of the silicon wafer to achieve enhanced polishing and selective polishing effects. Traditional silicon wafers are transported in series during the processing process. This transmission process increases the waiting time of the polishing head, reduces transmission efficiency, and reduces overall production capacity. Utility Model Content

[0004] The embodiment of the utility model provides a chemical mechanical planarization device, which aims to solve the technical problem that the polishing and transmission process of existing silicon wafers is a series operation route, which increases the waiting time of the polishing head, reduces the transmission efficiency, and reduces the overall production capacity.

[0005] The utility model provides a chemical mechanical planarization device, comprising a front end unit, a cleaning unit, a polishing unit, a first transfer component arranged between the front end unit and the cleaning unit, a second transfer component arranged in the cleaning unit, and a third transfer component arranged in the polishing unit, wherein the polishing unit has at least one, the number of the cleaning units is the same as that of the polishing units, the polishing unit comprises a rotating frame, a plurality of polishing heads fixed to the rotating frame, and a plurality of polishing tables located below the polishing heads, the plurality of polishing heads are evenly distributed around the rotating shaft of the rotating frame, the number of the polishing tables is one less than the number of the polishing heads to form a loading and unloading position, the third transfer component has a first working point and a second working point, the first working point being the loading and unloading position;

[0006] Among them, the first transfer component takes the wafer from the front-end unit and places it at the third working point, the second transfer component takes the wafer located at the third working point and places it at the second working point, the third transfer component takes the wafer located at the second working point and places it at the first working point, when one of the empty polishing heads on the rotating frame moves to the first working point, it takes the wafer and drives the wafer to rotate and switch between the multiple polishing tables until it rotates back to the first working point, the polishing head places the polished wafer back to the first working point, the third transfer component moves the polished wafer to the second working point, the second transfer component takes the wafer at the second working point, cleans and dries it, and then moves it to the third working point, and the first transfer component takes the wafer at the third working point for storage.

[0007] In a possible implementation, the third transfer component reciprocates in a direction parallel to the first straight path, and the first working point and the second working point are two moving end values ​​of the third transfer component.

[0008] In a possible implementation, the cleaning unit includes a plurality of cleaning slots and a drying slot, and the plurality of cleaning slots are located on a side of the drying slot close to the polishing unit.

[0009] In a possible implementation, two of the polishing units and two of the cleaning units are provided, the third transfer component in the polishing unit is located on a side close to the other polishing unit, and the cleaning tank and the drying tank in the cleaning unit are located on a side away from the other cleaning unit.

[0010] In a possible implementation, the first transport component and the second transport component include:

[0011] Linear guides;

[0012] A moving member, slidably connected to the linear guide rail;

[0013] A manipulator connected to the moving part;

[0014] Wherein, the linear guide rail in the first transfer component is perpendicular to the first linear path and parallel to the horizontal direction, and the linear guide rail in the second transfer component is parallel to the first linear path.

[0015] In a possible implementation, the robot includes at least three rotating arms, the rotating arm located at one end is hinged to the moving part, and the rotating arm located at the other end is used for picking up and placing wafers.

[0016] In a possible implementation, a line connecting the center of the polishing head and the center of the rotating frame is preset as a first reference line, a line connecting the polishing table and the center of the rotating frame is preset as a second reference line, and an angle between two adjacent first reference lines is equal to an angle between two adjacent second reference lines.

[0017] In a possible implementation, the axes of the plurality of polishing heads are equidistant from the axis of the rotating shaft of the rotating frame, and the axes of the plurality of polishing tables are equidistant from the axis of the rotating shaft of the rotating frame.

[0018] In a possible implementation, a dresser and a liquid supply pipe are provided on the periphery of each polishing table, the dresser is used to polish the polishing pad, and the liquid supply pipe is used to replenish the polishing liquid.

[0019] Compared with the prior art, the solution shown in the embodiment of the present application is provided with multiple polishing heads, and the multiple polishing heads are driven to rotate by a rotating frame, so that the wafer can be switched between multiple polishing tables for polishing, which not only improves the polishing efficiency, but also ensures the normal loading and unloading of the wafer at the first working point while polishing is in progress. Compared with traditional equipment, the waiting time of the polishing head is reduced and the polishing efficiency is improved. When performing operations, multiple cleaning units and multiple polishing units work together and can adapt alternately, thereby improving the overall production capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the top view of the chemical mechanical planarization device provided in an embodiment of the utility model;

[0021] Figure 2 This is a schematic diagram of the working steps of the polishing head used in the embodiment of the utility model.

[0022] Description of reference numerals:

[0023] 10- front end unit;

[0024] 20-cleaning unit; 21-cleaning tank; 22-drying tank;

[0025] 30-polishing unit; 31-rotating frame; 32-polishing head; 33-polishing table; 34-first working point; 35-second working point; 36-dresser; 37-liquid supply pipe;

[0026] 40-first transfer assembly; 41-second transfer assembly; 42-linear guide rail; 43-moving member; 44-manipulator; 45-rotating arm;

[0027] 50-third transport component;

[0028] 60-The third working point. DETAILED DESCRIPTION

[0029] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] In the claims, specification and the above drawings of the present utility model, unless otherwise clearly defined, the terms "first", "second" or "third" are used to distinguish different objects, rather than to describe a specific order. In the claims, specification and the above drawings of the present utility model, unless otherwise clearly defined, the directional words are only used to facilitate the description of the present utility model and simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, so they cannot be understood as limiting the specific protection scope of the present utility model.

[0031] In the claims, specification and the above drawings of the utility model, unless otherwise clearly defined, if the term "fixed connection" or "fixed connection" is used, it should be understood in a broad sense, that is, any connection method without a displacement relationship and relative rotation relationship between the two, that is to say, including non-detachable fixed connection, detachable fixed connection, integrated connection and fixed connection through other devices or elements.

[0032] In the claims, specification and drawings of the present utility model, if the terms "include", "have" and their variations are used, they are intended to mean "including but not limited to".

[0033] Please also read Figure 1 to Figure 2 , the chemical mechanical planarization device provided by the utility model is now described. The chemical mechanical planarization device includes a front end unit 10, a cleaning unit 20, a polishing unit 30, a first transfer component 40 arranged between the front end unit 10 and the cleaning unit 20, a second transfer component 41 arranged in the cleaning unit 20, and a third transfer component 50 arranged in the polishing unit 30. The polishing unit 30 is at least provided with one, and the number of cleaning units 20 and polishing units 30 is the same. The polishing unit 30 includes a rotating frame 31, a plurality of polishing heads 32 fixed to the rotating frame 31, and a plurality of polishing tables 33 located below the polishing heads 32. The plurality of polishing heads 32 are evenly distributed around the rotating shaft of the rotating frame 31. The number of polishing tables 33 is one less than the number of polishing heads 32 to form a loading and unloading position. The third transfer component 50 has a first working point 34 and a second working point 35. The first working point 34 is the loading and unloading position.

[0034] Among them, the first transfer component 40 takes the wafer from the front-end unit 10 and places it at the third working point 60, the second transfer component 41 takes the wafer located at the third working point 60 and places it at the second working point 35, the third transfer component 50 takes the wafer located at the second working point 35 and places it at the first working point 34, when one of the empty polishing heads 32 on the rotating frame 31 moves to the first working point 34, it takes the wafer and drives the wafer to rotate and switch between multiple polishing tables 33 until it rotates back to the first working point 34, the polishing head 32 places the polished wafer back to the first working point 34, the third transfer component 50 moves the polished wafer to the second working point 35, the second transfer component 41 takes the wafer from the second working point 35, cleans and dries it, and then moves it to the third working point 60, and the first transfer component 40 takes the wafer from the third working point 60 for storage.

[0035] It should be noted that Figure 1 The direction indicated by the shears in the middle is the “first straight line path” in this application.

[0036] Compared with the prior art, the chemical mechanical planarization equipment provided in this embodiment has multiple polishing heads 32, which are driven to rotate by a rotating frame 31, so that the wafer can be switched between multiple polishing tables 33 for polishing, which not only improves the polishing efficiency, but also ensures the normal loading and unloading of the wafer at the first working point 34 during polishing. Compared with traditional equipment, the waiting time of the polishing head 32 is reduced, and the polishing efficiency is improved. When operating, multiple cleaning units 20 and multiple polishing units 30 work together and can adapt alternately, thereby improving the overall production capacity.

[0037] The polishing head 32 can rotate in two ways: forward rotation less than 360° and then reverse the same angle; or forward rotation or reverse rotation all the time. The combination of forward rotation and reverse rotation can not only improve the processing efficiency of the wafer, but also increase the number of polishing times for each wafer and improve the processing efficiency; the forward rotation and reverse rotation methods require the addition of conductive slip rings to avoid cable entanglement, which will not only reduce the processing efficiency, but also increase the cost accordingly.

[0038] In some embodiments, a specific implementation of the third transport component 50 can be as follows: Figure 1 See the structure shown. Figure 1, the third transfer component 50 reciprocates along a direction parallel to the first straight path, and the first working point 34 and the second working point 35 are two moving end values ​​of the third transfer component 50. Since the front-end unit 10, the cleaning unit 20 and the polishing unit 30 are arranged along the first straight path, the moving route of the third transfer component 50 is parallel to the first straight path, which can make the moving path of the third transfer component 50 the shortest, and can realize the rapid switching between the third transfer component 50 and the second transfer component 41 to pick up and place the wafer, shorten the wafer transportation time of the overall equipment, and realize a fast and efficient processing process; when the third transfer component 50 moves to one end, it is the first working point 34, and when it moves to the other end, it is the second working point 35. By setting the first working point 34 and the second working point 35 at the ends of the moving path of the third transfer component 50, the positioning of the third transfer component 50 is facilitated, thereby ensuring the accurate placement of the wafer.

[0039] Specifically, in order to facilitate the start and stop of the third transfer component 50, sensors can be set at both ends of the moving path of the third transfer component 50. When the third transfer component 50 moves to the end point and contacts the sensor, the sensor can link the third transfer component 50 to control it to stop for a preset period of time and then move in the opposite direction to the other end point.

[0040] In some embodiments, a specific implementation of the cleaning unit 20 can be as follows: Figure 1 See the structure shown. Figure 1 The cleaning unit 20 includes a plurality of cleaning tanks 21 and a drying tank 22, and the plurality of cleaning tanks 21 are located on the side of the drying tank 22 close to the polishing unit 30. When the wafer is polished, the second transfer assembly 41 moves the wafer to start cleaning from the first cleaning tank 21 close to the polishing unit 30, and then passes through the plurality of cleaning tanks 21 in sequence and enters the drying tank 22 for drying. The surface quality of the wafer can be improved through multiple cleanings, and the debris during polishing can be prevented from adhering to the processing surface of the wafer, and the polishing liquid adhering to the wafer can also be removed.

[0041] In some embodiments, a specific implementation of the polishing unit 30 and the cleaning unit 20 can be as follows: Figure 1 See the structure shown. Figure 1, the polishing unit 30 and the cleaning unit 20 are each provided with two, the third transfer component 50 in the polishing unit 30 is located on the side close to the other polishing unit 30, and the cleaning tank 21 and the drying tank 22 in the cleaning unit 20 are located on the side away from the other cleaning unit 20. Since the third transfer component 50 in the polishing unit 30 only needs to drive the wafer to move in a straight line, and the cleaning unit 20 component needs to transfer the wafer in a straight line between the second working point 35 and the third working point 60 (before wafer polishing), and also needs to drive the polished wafer to move between the cleaning tank 21 and the drying tank 22, the cleaning tank 21 and the drying tank 22 in the two cleaning units 20 are arranged in a back-to-back manner, so that the two second transfer components 41 have enough moving space, and the second transfer component 41 in one of the cleaning units 20 can realize that while the second transfer component 41 in one of the cleaning units 20 transfers the wafer in a straight line (before wafer polishing), the second transfer component 41 in the other cleaning unit 20 drives the polished wafer to switch between the cleaning tank 21 and the drying tank 22, which is also applicable to the two second transfer components 41 performing the same operation content, the layout is reasonable, the route arrangement is convenient, the transfer time is shortened, and the processing efficiency is improved.

[0042] In some embodiments, a specific implementation of the first transport component 40 and the second transport component 41 can be as follows: Figure 1 See the structure shown. Figure 1 The first transfer component 40 and the second transfer component 41 both include a linear guide 42, a moving part 43, and a manipulator 44. The moving part 43 is slidably connected to the linear guide 42; the manipulator 44 is connected to the moving part 43; wherein the linear guide 42 in the first transfer component 40 is perpendicular to the first linear path and parallel to the horizontal direction, and the linear guide 42 in the second transfer component 41 is parallel to the first linear path. Taking the first transfer component 40 as an example, the moving part 43 can drive the manipulator 44 to move along the linear guide 42, and the manipulator 44 can select models with multiple degrees of freedom, thereby satisfying multi-degree-of-freedom operations within the linear range of the linear guide 42, which can not only realize the linear transfer of the wafer, but also drive the wafer to perform corresponding operations within the range.

[0043] Specifically, the manipulator 44 includes at least three rotating arms 45, the rotating part at one end is hinged to the moving part 43, and the rotating arm 45 at the other end is used to pick up and place the wafer. The manipulator 44 of this structure can rotate 360 ​​degrees on the moving part 43, and the three rotating arms 45 on the manipulator 44 are hinged in sequence, which can facilitate avoiding surrounding obstacles in the process of picking up and placing the wafer, making the working process more flexible and driving the wafer to achieve a perfect fit with other structures.

[0044] In some embodiments, an improved embodiment of the polishing table 33 can be adopted as follows Figure 1 See the structure shown. Figure 1, the line connecting the center of the polishing head 32 and the center of the rotating frame 31 is preset as the first reference line, the line connecting the center of the polishing table 33 and the center of the rotating frame 31 is preset as the second reference line, and the angle between two adjacent first reference lines is equal to the angle between two adjacent second reference lines. Multiple polishing heads 32 are evenly distributed around the rotating axis of the rotating frame 31, and the angle between two adjacent polishing tables 33 is equal to the angle between two adjacent polishing heads 32, which can ensure that when each polishing head 32 switches to the next polishing table 33, each polishing table 33 can correspond to a polishing head 32, so that multiple wafers can be processed simultaneously, and the processing efficiency is higher.

[0045] Specifically, the axes of the multiple polishing heads 32 are spaced at equal distances from the axis of the rotating shaft of the rotating frame 31, and the axes of the multiple polishing tables 33 are spaced at equal distances from the axis of the rotating shaft of the rotating frame 31. This structure allows the wafers on each polishing head 32 to be spaced at equal distances from the axes of the polishing tables 33 when they are polished on different polishing tables 33, thereby ensuring that the wafers are roughly positioned at the same position on different polishing tables 33, and ensuring that the polishing surface processing effects of different polishing tables 33 on the wafers are consistent, thereby ensuring the processing quality.

[0046] During the actual processing, the polishing head 32 and the polishing table 33 are not concentric, that is, the wafer and the polishing table 33 are not concentric. According to the principle that the farther away from the center of the polishing table 33, the greater the linear speed, the distance between the wafer and the center of the polishing table 33 is adjusted appropriately to ensure efficient processing of the wafer.

[0047] In some embodiments, an improved embodiment of the polishing table 33 can be adopted as follows Figure 1 See the structure shown. Figure 1 Each polishing table 33 is provided with a dresser 36 and a liquid supply pipe 37 on its periphery. The dresser 36 is used to polish the polishing pad, and the liquid supply pipe 37 is used to replenish the polishing liquid. In the process of polishing the wafer, the polishing pad needs to be installed on the polishing table 33. A driving device is provided at the bottom to drive the polishing table 33 to rotate. The polishing pad can be polished by the dresser 36, and the liquid supply pipe 37 can continuously add the polishing liquid to ensure the polishing quality of the wafer.

[0048] In specific implementation, the area swept by the rotating frame 31 and the multiple polishing heads 32 is a preset rotation area, and the trimmer 36 and liquid supply pipe 37 of each polishing table 33 are arranged on the periphery of the preset rotation area to avoid interference with the polishing head 32 during rotation.

[0049] As an example, a specific working process of the chemical mechanical planarization device of the utility model is as follows:

[0050] S10: The first transfer component 40 places the wafer to be processed in the front-end unit 10 at a third operation point;

[0051] S20: Each cleaning unit 20 corresponds to a second transfer assembly 41, and a plurality of second transfer assemblies 41 alternately take the wafers to be processed at the third operation point;

[0052] S30: Each second transfer assembly 41 places the wafer to be processed on the first point in the corresponding polishing unit 30;

[0053] S40: The third transfer assembly 50 in each polishing unit 30 takes the wafer to be processed at the first position and moves it to the first working position 34;

[0054] S50: When an empty polishing head 32 on the rotating frame 31 rotates to the position just above the first working point 34, the polishing head 32 takes the wafer to be processed on the first working point 34;

[0055] S60: The rotating frame 31 rotates to drive the wafer to be processed to switch between the multiple polishing tables 33 in sequence, and at the same time, the remaining empty polishing head 32 continues to grab the wafer to be processed on the first working point 34 when passing directly above the first working point 34;

[0056] S70: After the first wafer to be processed is polished on each polishing table 33, the rotating frame 31 rotates in the opposite direction of step S60 until the wafer moves back to just above the first working point 34, and the polishing head 32 puts down the polished wafer;

[0057] S80: The third transfer assembly 50 drives the polished wafer to move to the second working point 35, and the second transfer assembly 41 grabs the wafer on the second working point 35 to the cleaning unit 20 for cleaning and drying, and then places the cleaned and dried wafer on the third working point 60;

[0058] S90: The first transfer component 40 grabs the wafer on the third working point 60 and puts it into the front-end unit 10 for storage.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A chemical mechanical planarization device, characterized in that: The invention comprises a front end unit, a cleaning unit, a polishing unit, a first transfer assembly arranged between the front end unit and the cleaning unit, a second transfer assembly arranged at the cleaning unit, and a third transfer assembly arranged at the polishing unit, wherein the polishing unit has at least one, the number of the cleaning units is the same as the number of the polishing units, the polishing unit comprises a rotating frame, a plurality of polishing heads fixed to the rotating frame, and a plurality of polishing tables located below the polishing heads, the plurality of polishing heads are evenly distributed around the rotating shaft of the rotating frame, the number of the polishing tables is one less than the number of the polishing heads to form a loading and unloading position, the third transfer assembly has a first working point and a second working point, the first working point being the loading and unloading position; Among them, the first transfer component takes the wafer from the front-end unit and places it at the third working point, the second transfer component takes the wafer located at the third working point and places it at the second working point, the third transfer component takes the wafer located at the second working point and places it at the first working point, when one of the empty polishing heads on the rotating frame moves to the first working point, it takes the wafer and drives the wafer to rotate and switch between the multiple polishing tables until it rotates back to the first working point, the polishing head places the polished wafer back to the first working point, the third transfer component moves the polished wafer to the second working point, the second transfer component takes the wafer at the second working point, cleans and dries it, and then moves it to the third working point, and the first transfer component takes the wafer at the third working point for storage.

2. The chemical mechanical planarization device according to claim 1, characterized in that: The third transfer component reciprocates in a direction parallel to the first straight path, and the first working point and the second working point are two moving end values ​​of the third transfer component.

3. The chemical mechanical planarization device according to claim 1, characterized in that: The cleaning unit comprises a plurality of cleaning slots and a drying slot, wherein the plurality of cleaning slots are located on a side of the drying slot close to the polishing unit.

4. The chemical mechanical planarization device according to claim 3, characterized in that: There are two polishing units and two cleaning units, the third transfer assembly in the polishing unit is located on a side close to the other polishing unit, and the cleaning tank and the drying tank in the cleaning unit are located on a side away from the other cleaning unit.

5. The chemical mechanical planarization apparatus according to claim 1, characterized in that: The first transfer component and the second transfer component include: Linear guides; A moving member, slidably connected to the linear guide rail; A manipulator connected to the moving part; Wherein, the linear guide rail in the first transfer component is perpendicular to the first linear path and parallel to the horizontal direction, and the linear guide rail in the second transfer component is parallel to the first linear path.

6. The chemical mechanical planarization apparatus according to claim 5, characterized in that: The robot comprises at least three rotating arms, the rotating arm at one end is hinged to the moving part, and the rotating arm at the other end is used for taking and placing wafers.

7. The chemical mechanical planarization apparatus according to claim 1, characterized in that: The line connecting the center of the polishing head and the center of the rotating frame is preset as the first reference line, the line connecting the polishing table and the center of the rotating frame is preset as the second reference line, and the angle between two adjacent first reference lines is equal to the angle between two adjacent second reference lines.

8. The chemical mechanical planarization apparatus according to claim 7, characterized in that: The axes of the plurality of polishing heads are spaced at equal distances from the axis of the rotating shaft of the rotating frame, and the axes of the plurality of polishing tables are spaced at equal distances from the axis of the rotating shaft of the rotating frame.

9. The chemical mechanical planarization apparatus according to claim 1, characterized in that: A dresser and a liquid supply pipe are provided on the periphery of each polishing table. The dresser is used for grinding the polishing pad, and the liquid supply pipe is used for replenishing the polishing liquid.

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