Polishing mechanism, polishing module, polishing method, processor and storage medium

Abstract

The embodiment of the invention provides a polishing mechanism, a polishing module, a polishing method, a processor and a storage medium. The polishing mechanism comprises a supporting body, at least two long-strip-shaped through holes evenly distributed in the circumferential direction are formed in the supporting body, and the axis of each long-strip-shaped through hole penetrates through the center of the supporting body. The at least two polishing heads are movably arranged in the long-strip-shaped through holes in a one-to-one correspondence mode; the first driving mechanism is arranged on the supporting body, electrically connected with the polishing heads and used for driving the polishing heads to rotate and move in a reciprocating mode along the long-strip-shaped through holes at the same time. According to the polishing device, all the polishing heads reciprocate along the long-strip-shaped through holes, so that the polishing heads can reciprocate in the radial direction of the polishing pad in the polishing operation process, namely in the radial direction of the annular groove used for containing the polishing solution, all the polishing heads can make full contact with the polishing solution, and the more efficient polishing effect is achieved; especially for wafers made of third-generation semiconductor materials, the polishing efficiency is remarkably improved through the polishing mode.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of semiconductor processing technology, and in particular to a polishing mechanism, a polishing module, a polishing method, a processor, and a storage medium. Background Art

[0002] In the field of semiconductor processing technology, chemical mechanical polishing (CMP) is a key surface treatment process that combines chemical reaction and mechanical action to flatten the wafer surface. In this process, the polishing liquid reacts with the material on the wafer surface, while the material is removed through the relative movement between the polishing pad and the wafer.

[0003] At present, for semiconductor materials with extremely high hardness and difficult polishing, such as third-generation semiconductor materials, including silicon carbide, gallium nitride, diamond, zinc oxide, aluminum nitride, etc., the polishing equipment in the relevant technology cannot meet the polishing requirements of such materials, and the polishing efficiency is low. In addition, the polishing quality is unstable and the consistency of the polished wafers is poor. Summary of the invention

[0004] In view of this, embodiments of the present application provide a polishing mechanism, a polishing module, a polishing method, a processor and a storage medium to at least partially solve the above problems.

[0005] According to a first aspect of an embodiment of the present application, a polishing mechanism is provided for pressing a wafer against a polishing pad for polishing, comprising: a support body, having at least two elongated through holes evenly distributed in a circumferential direction, and the axis of each of the elongated through holes passes through the center of the support body; at least two polishing heads, one-to-one correspondingly and movably arranged in each of the elongated through holes; a first driving mechanism, mounted on the support body and connected to each of the polishing heads, for driving each of the polishing heads to rotate and simultaneously reciprocate along the elongated through holes.

[0006] Furthermore, in the above-mentioned polishing mechanism, each of the polishing heads maintains an equal distance from the center of the support body during the reciprocating movement along the elongated through hole.

[0007] Furthermore, in the above-mentioned polishing mechanism, the first driving mechanism includes: at least two motors, each of the motors is placed on the first side of the support body and the output shaft passes through the support body and is connected one-to-one with the rotating shaft of each polishing head placed on the second side of the support body, and each of the motors is used to drive each of the polishing heads to rotate; a driving unit, which is installed on the support body and connected to the outer casing of each of the motors, and is used to drive each of the motors to reciprocate along the elongated through hole, thereby driving the polishing head to reciprocate along the elongated through hole.

[0008] Furthermore, in the above-mentioned polishing mechanism, both ends of the elongated through hole are semicircular to match the output shaft of the motor and / or the rotating shaft of the polishing head.

[0009] Furthermore, the above-mentioned polishing mechanism further includes: a polishing liquid supply device, which is fixedly arranged in the central area of ​​the support body and is used to transport polishing liquid to the polishing pad.

[0010] Furthermore, in the above-mentioned polishing mechanism, the polishing liquid supply device includes: a circular polishing liquid tube, which is arranged in the central area of ​​the support body; at least two nozzles, each of which is connected to the outer side of the circular polishing liquid tube and is evenly distributed along the circumference, and the nozzles are arranged one-to-one with the areas between adjacent polishing heads, and each of the nozzles is arranged at a preset angle to the moving direction of the polishing head on the support body.

[0011] Furthermore, in the above-mentioned polishing mechanism, the preset angle is 15° to 45°.

[0012] Furthermore, in the above-mentioned polishing mechanism, the support body includes: a main body; at least two connecting bodies, both connected to the main body and evenly distributed along the circumference of the main body, and each of the connecting bodies is provided with one of the elongated through holes, and the axis of each of the elongated through holes passes through the center of the main body.

[0013] According to the second aspect of the embodiment of the present application, a polishing module is provided, comprising: a base, a polishing disc arranged on the base, a polishing pad arranged on the polishing disc, a second driving mechanism for controlling the rotation of the polishing disc, and any one of the above-mentioned polishing mechanisms; wherein, the polishing pad has a surface facing the polishing mechanism formed with a plurality of annular grooves concentric with the polishing pad for accommodating polishing liquid, the polishing mechanism is placed above the polishing pad, and the supporting body of the polishing mechanism can be arranged coaxially with the polishing pad so that the axis of the elongated through hole on the supporting body is arranged along the radial direction of the annular groove, thereby enabling each of the polishing heads to reciprocate along the radial direction of the groove.

[0014] Furthermore, the above-mentioned polishing module also includes: a loading and unloading platform, which is arranged on the base and placed on one side of the polishing disk, and is used to carry wafers; a third driving mechanism, which is connected to the support body, and is used to drive the support body to move between the polishing pad and the loading and unloading platform, so as to receive the wafers to be polished from the loading and unloading platform, or transfer the polished wafers to the loading and unloading platform; the third driving mechanism is also used to drive the support body to rotate, so that each of the polishing heads is placed above the loading and unloading platform in turn, and exchanges wafers with the loading and unloading platform.

[0015] According to the second aspect of the embodiment of the present application, a polishing method is provided, which includes the following steps: controlling each polishing head on a support body to load a wafer; controlling each polishing head to move along its own long strip through hole with the wafer to an initial position; wherein each polishing head is at an equal distance from the center of the support body at the initial position; controlling the support body to drive the polishing head to move above the polishing pad, and making the support body coaxial with the polishing pad, and then controlling the support body to move toward the direction of the polishing pad, and making the polishing head press the wafer against the polishing pad; controlling the polishing liquid supply device to deliver polishing liquid to the polishing pad; controlling the polishing disk to rotate; controlling each polishing head to rotate and move back and forth along the long strip through hole at the same time, and always keeping the distance between each polishing head and the center of the support body equal during the movement; and controlling each polishing head to unload the wafer after polishing is completed.

[0016] Furthermore, in the above-mentioned polishing method, the step of controlling each polishing head on the support body to load the wafer further includes: controlling the support body to move above the polishing pad, and then moving relative to the polishing pad toward the loading and unloading platform; controlling the support body to rotate so that each of the polishing heads is placed above the loading and unloading platform in turn, and loading the wafer from the loading and unloading platform.

[0017] Furthermore, in the above-mentioned polishing method, the step of controlling each polishing head to unload the wafer after polishing is completed further includes: controlling the support body to move toward the loading and unloading platform relative to the polishing pad; controlling the support body to rotate so that each polishing head is placed above the loading and unloading platform in turn to unload the wafer onto the loading and unloading platform.

[0018] According to a third aspect of an embodiment of the present application, a processor is provided, which is used to execute relevant steps of any of the above-mentioned polishing methods.

[0019] According to a fourth aspect of an embodiment of the present application, a computer storage medium is provided, on which a computer program is stored, and when the program is executed by a processor, any of the above-mentioned polishing methods is implemented.

[0020] In the embodiment of the present application, each polishing head reciprocates along the long strip through hole, so that the polishing head can reciprocate along the radial direction of the polishing pad, that is, along the radial direction of the annular groove for accommodating the polishing liquid during the polishing operation, so that each polishing head can be fully in contact with the polishing liquid, thereby achieving a more efficient polishing effect. Especially for third-generation semiconductor materials, this polishing method significantly improves the polishing efficiency. In addition, since each polishing head moves along the radial direction of the annular groove, the polishing effect of each polishing head is guaranteed to be stable, thereby ensuring that the wafers polished by each polishing head have good consistency, thereby improving the quality of the wafers.

[0021] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other objects, features and advantages of the present application will become more apparent by describing in more detail exemplary embodiments of the present application in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present application.

[0023] Figure 1 A schematic diagram of the three-dimensional structure of the polishing mechanism provided in an embodiment of the present application;

[0024] Figure 2 A schematic diagram of the planar structure of the polishing mechanism provided in an embodiment of the present application;

[0025] Figure 3 A schematic structural diagram of a polishing liquid supply device in a polishing mechanism provided in an embodiment of the present application;

[0026] Figure 4 A schematic diagram of the three-dimensional structure of a polishing module provided in an embodiment of the present application;

[0027] Figure 5 Another schematic diagram of the three-dimensional structure of the polishing module provided in the embodiment of the present application;

[0028] Figure 6 A schematic diagram of the structure of a polishing pad and a polishing head in a polishing module provided in an embodiment of the present application;

[0029] Figure 7 A schematic diagram of the planar structure of a polishing module provided in an embodiment of the present application;

[0030] Figure 8 A schematic diagram of a state in which the polishing mechanism of the polishing module provided in an embodiment of the present application is moved to the loading and unloading platform;

[0031] Fig. 9 A flow chart of a polishing method provided in an embodiment of the present application;

[0032] In the above picture:

[0033] Polishing mechanism 100; support body 110; long strip through hole 111; body 112; connector 113; polishing head 120; first drive mechanism 130; motor 131; polishing liquid supply device 140; annular polishing liquid pipe 141; nozzle 142; base 200; polishing disc 300; polishing pad 400; dresser 500; loading and unloading platform 600. DETAILED DESCRIPTION

[0034] The preferred embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0035] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0036] It should be understood that although the terms "first", "second", "third", etc. may be used in the present application to describe various components, these components should not be limited to these terms. These terms are only used to distinguish components of the same type from each other. For example, without departing from the scope of the present application, the first component may also be referred to as the second component, and similarly, the second component may also be referred to as the first component. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0037] In the description of the present application, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0038] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0039] At present, semiconductor materials with a bandgap width (Eg) greater than or equal to 2.3eV are called wide bandgap semiconductor materials, also known as third-generation semiconductor materials. Common third-generation semiconductor materials include: silicon carbide, gallium nitride, diamond, zinc oxide, aluminum nitride, etc. Devices developed from third-generation semiconductor materials have the advantages of high voltage resistance, high temperature resistance, high power, radiation resistance, strong conductivity, fast working speed, low working loss, etc., and have huge application potential.

[0040] However, due to the extremely high hardness and difficulty in polishing of third-generation semiconductor materials, the use of CMP equipment in related technologies to polish wafers made of third-generation semiconductor materials not only has low polishing efficiency but also poor consistency.

[0041] In view of the above problems, an embodiment of the present application provides a polishing mechanism that can improve polishing efficiency while having better consistency.

[0042] The technical solution of the embodiments of the present application is described in detail below with reference to the accompanying drawings.

[0043] See also Figure 1 and Figure 2 According to an embodiment of the present application, a polishing mechanism 100 includes a support body 110, at least two polishing heads 120, and a first driving mechanism 130. The polishing mechanism 100 is used to press a wafer against a polishing pad for polishing. During polishing, the polishing mechanism 100 is placed above the polishing pad, and the polishing head 120 is loaded with a wafer. The polishing head 120 presses the wafer against the polishing pad, and mechanically chemically polishes the wafer through the combination of the polishing liquid on the polishing pad and the pressing force. Among them, the polishing head 120 can fix the wafer by adsorption, clamping, etc.

[0044] In this embodiment, the support body 110 is provided with at least two elongated through holes 111 evenly distributed along the circumferential direction, and the axis of each elongated through hole passes through the center of the support body 110, and each polishing head 120 is movably disposed in each elongated through hole 111 in correspondence with each other. The first driving mechanism 130 is installed on the support body 110 and connected to each polishing head 120, and is used to drive each polishing head 120 to rotate and also to rotate along the length direction ( Figure 2 The device moves back and forth in the directions a, b, and c as shown in the figure.

[0045] In a specific implementation, the support body 110 may include: a body 112 and at least two connectors 113. The number of connectors 113 is the same as the number of polishing heads 120. Each connector 113 is connected to the body 112 and is evenly distributed along the circumference of the body 112. Each connector 113 is provided with a long strip through hole 111. Each polishing head 120 is movably disposed in each long strip through hole 111 and can reciprocate along the length direction of the long strip through hole. The axis of the long strip through hole 111 passes through the center O of the body 112.

[0046] For example, see Figure 2 , Figure 2 is a schematic diagram of the planar structure of the support body 110, Figure 2 1 is an example of three connectors 113, and the three connectors 113 are evenly distributed along the circumference of the body 112. The axes of the three long strip through holes 111 are AA', BB', and CC', and the three axes all pass through the center O of the support body 110. The length directions of the three long strip through holes 111 are Figure 2 In the directions a, b and c shown in FIG. 1 , the three polishing heads 120 can be respectively moved along Figure 2 The surfaces of the three polishing heads 120 away from the support body 110 should be in one plane so that the three wafers carried by the three polishing heads 120 can fully contact the polishing pad.

[0047] During polishing, the polishing head 120 is pressed against the polishing pad, and the support body 110 is arranged coaxially with the polishing pad. Since the axes of the three long strip connecting holes 111 intersect at the center of the support body 110, when the support body 110 is coaxial with the polishing pad, the axes of the long strip through holes 111 are arranged along the radial direction of the polishing pad, so that the polishing head 120 reciprocates along the long strip through holes 111, that is, reciprocates along the radial direction of the polishing pad. It can be understood that the surface of the polishing pad pressed by the polishing head 120 is formed with a plurality of annular grooves concentric with the polishing pad, and the grooves can be used to contain polishing liquid. When the polishing head 120 moves along the radial direction of the polishing pad, it also reciprocates along the radial direction of the annular grooves.

[0048] In another specific implementation, the support body 110 may also be in a disc shape, and the elongated through holes 111 are evenly distributed along the circumference of the disc, and the axes of the elongated through holes 111 are arranged along the radial direction of the disc.

[0049] It should be noted that, in a specific implementation, the support body 110 may also be in other shapes, as long as it can ensure that the polishing head 120 can move radially along the annular groove. This embodiment does not impose any limitation on the specific shape of the support body 110.

[0050] It should be noted that in an optional specific implementation, the number of connectors 113 and the number of elongated through holes 111 are the same, which can be two, four, or more than four. Each connector 113 is provided with an elongated through hole 111, and this embodiment does not impose any limitation on the specific number.

[0051] In this embodiment, the polishing head 120 is driven to rotate by the first driving mechanism 130 , and at the same time, the polishing head 120 reciprocates along the length direction of the long strip through hole 111 .

[0052] In the embodiment of the present application, each polishing head 120 can reciprocate along the long strip through hole 111, so that the polishing head 120 can reciprocate along the radial direction of the polishing pad, that is, along the radial direction of the annular groove for accommodating the polishing liquid during the polishing operation, so that each polishing head 120 can fully contact with the polishing liquid, thereby achieving a more efficient polishing effect. Especially for third-generation semiconductor materials, this polishing method significantly improves the polishing efficiency. In addition, since each polishing head 120 moves along the radial direction of the annular groove, the wafer carried by each polishing head 120 has the same angle as the polishing pad groove during mobile polishing, which ensures that the polishing effect of each polishing head 120 is stable, thereby ensuring that the wafers polished by each polishing head 120 have good consistency, thereby improving the overall quality of the wafer.

[0053] In some embodiments, each polishing head 120 maintains an equal distance from the center of the support body 110 during the reciprocating movement along the elongated through hole 111 .

[0054] In a specific implementation, the lengths of the elongated through holes 111 may be equal, and the first ends ( Figure 2 The distance from the second end of each long through hole 111 (the end close to the center of the support body shown in FIG. 1 ) to the center of the support body 110 is equal. Of course, the second end of each long through hole 111 ( Figure 2 The distance from the end away from the center of the support body (as shown in FIG. 1 ) to the center of the support body may also be equal.

[0055] Before polishing begins, the distance between the position of each polishing head 120 in the elongated through hole 111 and the center of the support body 110 can be made equal, and then the polishing heads 120 can be controlled to move synchronously, for example, at the same speed, so as to keep the distance between each polishing head 120 and the center of the support body 110 equal during the entire movement process.

[0056] In this embodiment, when each polishing head 120 reciprocates in the long strip through hole 111, it always maintains an equal distance from the center of the support body 110. This movement mode enables each polishing head 120 to always be located on the same circumference with the center of the support body 110 as the center during the movement, ensuring uniform mass distribution of the polishing mechanism 100 to suppress vibration caused by uneven mass, thereby ensuring the stability of the polishing mechanism 100 during the polishing process, thereby improving the quality and efficiency of the entire wafer polishing, and also ensuring that the wafers polished by each polishing head 120 have good consistency, preventing differences in film thickness of wafers loaded for polishing at the same time.

[0057] In some embodiments, see Figure 1 The first driving mechanism 130 includes: at least two motors 131 and a driving unit. The number of motors 131 is the same as the number of polishing heads 120, and each motor is placed on the first side of the support body 110 (for example Figure 1 The output shaft is disposed through the support body 110 and is disposed on the second side of the support body 110 (eg Figure 1 The rotating shafts of the polishing heads 120 (shown at the lower side) are connected one by one, and the motors 131 are respectively used to drive the polishing heads 120 to rotate.

[0058] The driving unit (not shown) is mounted on the support body 110 and connected to the housing of each motor 131 , and is used to drive each motor 131 to reciprocate along the elongated through hole 111 , thereby driving the polishing head 120 to reciprocate along the elongated through hole 111 .

[0059] In a specific implementation, the driving unit may also be an electric mechanism, a pneumatic mechanism, etc., the same number as the polishing heads 120, each electric mechanism or pneumatic mechanism may be connected to the housing of the motor 131, and the electric mechanism or pneumatic mechanism may drive the motor 131 to move back and forth along the long strip through hole 111, thereby driving the polishing head 120 installed at the output end of the motor 131 to move back and forth along the long strip through hole 111. Of course, a bracket may also be provided at the output end of the electric mechanism or pneumatic mechanism, the motor 131 is installed on the bracket, and the electric mechanism or pneumatic mechanism drives the motor 131 to move back and forth along the long strip through hole 111 by driving the bracket.

[0060] In some embodiments, the two ends of the elongated through hole 111 can be semicircular to adapt to the output shaft of the motor 131 and / or the rotating shaft of the polishing head, so that the output shaft of the motor 131 and / or the rotating shaft of the polishing head can better abut against the semicircular holes at both ends when moving to the two ends of the elongated through hole 111, thereby ensuring the stability of the motor 131 when it moves to the end, improving the stability of the polishing head 120, and making the material removal rate of the polished wafer stable, thereby improving the polishing quality of the wafer.

[0061] In a specific implementation, the output shaft of the motor 131 can be placed in the elongated through hole 111, and then can be abutted against the semicircles at both ends of the elongated through hole 111; the rotating shaft of the polishing head 120 can be placed in the elongated through hole 111, and then can be abutted against the semicircle; or the output shaft of the motor 131 and the rotating shaft of the polishing head 120 can be partially or completely placed in the elongated through hole 111, so that the output shaft of the motor 131 and the rotating shaft of the polishing head 120 can both be abutted against the semicircle.

[0062] Since the polishing equipment in the related technology is large in size, the polishing liquid is generally delivered by swinging arms, which has a relatively complex structure. For wafers supported by third-generation semiconductor materials, smaller polishing equipment is mainly used, because smaller polishing equipment can more accurately control various parameters in the polishing process, reduce material loss in the polishing process, and improve material utilization; in addition, smaller polishing equipment can usually provide a more uniform polishing effect.

[0063] Based on this, see Figure 4 In some embodiments, the polishing liquid supply device 140 is further included. The polishing liquid supply device 140 is fixedly disposed in the central area of ​​the support body 110 and is used to deliver the polishing liquid to the polishing pad.

[0064] It should be noted that the central area of ​​the support body 110 in this embodiment refers to the area near the center of the support body 110. The distance from the area to the center of the support body 110 can be determined according to actual conditions. The larger the diameter of the polishing pad, the larger the area can be, and the smaller the diameter of the polishing pad, the smaller the area can be. The shape of the area can be a circle with the center of the support body 100 as the center, or it can be an ellipse or other shapes, and this embodiment does not impose any limitation on it.

[0065] In this embodiment, the polishing liquid supply device 140 is fixed on the support body 110. Since the support body 110 and the polishing pad are coaxially arranged during polishing, the polishing liquid supply device 140 delivers the polishing liquid to the polishing pad, and the polishing liquid is evenly scattered on the polishing pad by the centrifugal force when the polishing pad rotates. Since the polishing equipment for the third-generation semiconductor materials is small in size, the fixed polishing liquid supply device 140 is adopted, and the centrifugal force when the polishing pad rotates can ensure that the polishing liquid is distributed from the center of the polishing pad to the entire polishing pad during polishing, thereby simplifying the equipment structure and saving equipment costs.

[0066] Further, in some embodiments, see Figure 3The polishing liquid supply device 140 may include: an annular polishing liquid pipe 141 and at least two nozzles 142. The number of nozzles 142 may be the same as the number of polishing heads 120. The annular polishing liquid pipe 141 and the nozzles 142 are both arranged in the central area of ​​the support body 110, and each nozzle 142 is uniformly connected to the outer side of the annular polishing liquid pipe 141 along the circumferential direction (relative to the outer side of the annular polishing liquid pipe 141). Figure 3 In the state shown in the figure), the nozzles 142 are arranged in one-to-one correspondence with the areas between adjacent polishing heads 120, and each nozzle 142 is arranged at a preset angle to the moving direction of the polishing head 120 on the support body 110, so that the polishing liquid sprayed by the nozzle 142 can be sprayed on the polishing pad 400 along a certain angle.

[0067] For example, see Figure 3 , three polishing heads 120 are shown in the figure, and accordingly, three nozzles 142 are connected to the outer side of the annular polishing liquid pipe 141, and each nozzle 142 corresponds to the area between adjacent polishing heads 120. Optionally, it can correspond to the middle position between the polishing heads 120.

[0068] In a specific implementation, the preset angle between each nozzle 142 and the moving direction of the corresponding polishing head 120 on the support body 110 can be 15° to 45°, that is, the nozzle 142 and the polishing head 120 are arranged at a predetermined angle. Figure 2 The axes AA', BB', and CC' shown are at a preset angle, so that the polishing liquid supplied by the nozzle 142 can enter the interior of the polishing head 120 in large quantities through the groove of the retaining ring at the bottom of the polishing head 120, avoiding the formation of a significant bow wave between the polishing liquid and the outer wall of the retaining ring, so that the polishing liquid is fully in contact with the wafer loaded by the polishing head 120 to ensure the polishing material removal rate. Preferably, the preset angle between each nozzle 142 and the corresponding moving direction of the polishing head 120 on the support body 110 can be 20° to 30°, so that the supplied polishing liquid can efficiently enter the interior of the polishing head 120, thereby improving the polishing rate of the wafer while ensuring the polishing quality of the wafer.

[0069] It should be noted that the retaining ring is an important component of the polishing head 120, which is arranged at the bottom of the base of the polishing head 120, and then surrounds the outer peripheral side of the elastic membrane arranged below the base, and the elastic membrane is a component for loading the wafer to be polished. The polishing liquid supplied by the nozzle 142 enters between the wafer and the polishing pad through the groove of the retaining ring, so that the abrasive of the polishing liquid is fully in contact with the wafer.

[0070] In the embodiment of the present application, the polishing liquid is directly supplied from the central area of ​​the support body 110, so that the landing points of each polishing liquid are evenly distributed between the polishing heads 120 and the polishing heads 120, and the polishing liquid is supplied toward a specific polishing head 120 through the centrifugal force of the polishing disk. Since the annular polishing liquid pipe 141 and the nozzle 142 are fixed to the support body 110, the distribution of the polishing liquid is guaranteed to be fixed.

[0071] The present application also provides a polishing module, see Figure 4 and Figure 5 The polishing module comprises: a base 200, a polishing disc 300 disposed on the base 200, a polishing pad 400 disposed on the polishing disc 300, and any of the above-mentioned polishing mechanisms 100. The polishing pad 400 has a plurality of annular grooves concentric with the polishing pad 400 formed on the surface facing the polishing mechanism for accommodating polishing liquid. The polishing mechanism is placed above the polishing pad 400, and the support body 110 of the polishing mechanism can be coaxially arranged with the polishing pad 400, so that the axis of the long strip through hole 111 on the support body 110 is arranged along the radial direction of the annular groove 410, so that each polishing head can reciprocate along the radial direction of the annular groove.

[0072] The specific implementation process of the polishing mechanism 100 can be found in the above description, and will not be described in detail in this embodiment.

[0073] In this embodiment, the surface of the polishing pad 400 facing the polishing mechanism 100 is formed with a plurality of annular grooves 410 concentric with the polishing pad 400 for containing the polishing liquid, see Figure 6 The annular groove 410 is exaggerated, and the actual size of the annular groove 410 is relatively small, and the annular groove 410 is spaced apart to cover the entire surface of the polishing pad 400. The axis of the long strip through hole 111 is arranged along the radial direction of the annular groove 410, so that each polishing head 120 reciprocates along the radial direction of the annular groove 410, that is, the radial direction of the polishing pad 400.

[0074] It is understood that the present embodiment may further include a dresser 500. The dresser 500 swings around a fixed point, and the dresser head configured thereon rotates itself and applies a downward load to dress the surface of the polishing pad 400, remove impurities, deposits and wear layers on the surface of the polishing pad 400, and keep the surface of the polishing pad 400 clean and flat, thereby ensuring the stability and consistency of the polishing effect.

[0075] In the embodiment of the present application, each polishing head 120 can move radially along the polishing pad 400 during the polishing operation, that is, reciprocate radially along the annular groove 410 for accommodating the polishing liquid, so that each polishing head 120 can be fully in contact with the polishing liquid, thereby achieving a more efficient polishing effect. In particular, for third-generation semiconductor materials, this polishing method significantly improves the polishing efficiency. In addition, since each polishing head 120 moves radially along the annular groove 410, this not only ensures that the polishing effect of each polishing head 120 is stable, but also ensures that the wafers polished using these polishing heads 120 have good consistency. Therefore, this embodiment not only optimizes the polishing process, but also improves the quality of the product and the reliability of production.

[0076] Further, see Figure 4 and Figure 5 In some embodiments, the loading and unloading platform 600 and the third driving mechanism (not shown in the figure) are also included. The loading and unloading platform 600 is arranged on the base 200 and placed on one side of the polishing plate 300, and is used to carry the wafer, that is, to place the wafer to be polished or polished. The third driving mechanism is connected to the support body 110, and is used to drive the support body 110 to move between the polishing pad 400 and the loading and unloading platform 600 (for example, along the Figure 7 The third driving mechanism is used to drive the support body 110 to rotate, so that each polishing head 120 is placed above the loading and unloading platform 600 in turn and exchanges wafers with the loading and unloading platform 600.

[0077] In this embodiment, the polishing mechanism 100 can move between the polishing plate 300 and the loading and unloading platform 600 to transfer wafers. That is, each polishing head 120 loads the wafer to be polished from the loading and unloading platform 600, and places the polished wafer on the loading and unloading platform 600, waiting for a wafer transfer device such as a robot or other transfer equipment to transfer the polished wafer to the next process for processing.

[0078] See also Figure 7 and Figure 8 , the third driving mechanism drives the support body 110 to move toward the loading and unloading platform 600, and can control the support body 110 to rotate around the center line, so that each polishing head 120 is placed above the loading and unloading platform 600 in sequence, and the wafer is loaded from the loading and unloading platform 600. Then the third driving mechanism drives the support body 110 to translate to the top of the polishing pad 400, and controls the support body 110 to move toward the polishing pad 400, so that each polishing head 120 is pressed against the polishing pad 400, and then controls each polishing head 120 to rotate through the first driving mechanism 130, and at the same time reciprocates along the long strip through hole 111 to polish each wafer. After polishing is completed, the third driving mechanism drives the support body 110 to move toward the loading and unloading platform 600, and can control the support body 110 to rotate, so as to transfer the polished wafers to the loading and unloading platform 600 in sequence.

[0079] The present application also proposes a polishing method, see Fig. 9 , the method comprises the following steps:

[0080] Step S910 , controlling each polishing head 120 on the support body 110 to load a wafer.

[0081] In a specific implementation, the support body 110 is controlled to move relative to the polishing pad 400 toward the loading and unloading platform 600 , and the support body 110 is controlled to rotate so that each polishing head 120 loads a wafer from the loading and unloading platform 600 in sequence.

[0082] Step S920, control each polishing head 120 to move with the wafer to the initial position along the respective long strip through hole 111. Wherein, each polishing head 120 is at the same distance from the center of the support body 110 when in the initial position.

[0083] In a specific implementation, the initial position can be any position of the long strip through hole 111, as long as the distances from each polishing head 120 to the center of the support body are equal, so that the mass distribution of the polishing mechanism 100 is relatively uniform.

[0084] Step S930 , control the support body 110 to drive the polishing head 120 to move above the polishing pad 400 , and make the support body 110 coaxial with the polishing pad 400 , then control the support body 110 to move toward the polishing pad 400 , and make the polishing head 120 press the wafer onto the polishing pad 400 .

[0085] Step S940 , controlling the polishing liquid supply device 140 to deliver the polishing liquid to the polishing pad 400 .

[0086] Specifically, the nozzle 142 sprinkles the polishing liquid between the polishing heads 120 and the polishing heads 120 .

[0087] Step S950, controlling the polishing disc 300 to rotate. The polishing disc 300 drives the polishing pad 400 to rotate, and the polishing liquid is evenly distributed on the polishing pad 400 by centrifugal force.

[0088] Step S960 , controlling each polishing head 120 to rotate and simultaneously reciprocate along the long strip through hole 111 , and keeping the distance between each polishing head 120 and the center of the support body 110 equal during the movement.

[0089] Among them, step S950 and step S960 can be executed simultaneously, or step S950 can be executed first, or step S960 can be executed first.

[0090] Step S970 , after polishing is completed, control each polishing head 120 to unload the wafer.

[0091] Specifically, the support body 110 is controlled to translate relative to the polishing pad 400 toward the loading and unloading platform 600 , and the support body 110 is controlled to rotate, so that each polishing head 120 unloads the polished wafer to the loading and unloading platform 600 .

[0092] In the embodiment of the present application, each polishing head 120 can move radially along the polishing pad 400 during the polishing operation, that is, reciprocate along the radial direction of the annular groove 410 for accommodating the polishing liquid, so that each polishing head 120 can be fully in contact with the polishing liquid, thereby achieving a more efficient polishing effect. In particular, for third-generation semiconductor materials, this polishing method significantly improves the polishing efficiency. In addition, since each polishing head 120 moves radially along the annular groove 410, this not only ensures that the polishing effect of each polishing head 120 is stable, but also ensures that the wafers polished using these polishing heads 120 have a high consistency. Therefore, this embodiment not only optimizes the polishing process, but also improves the quality of the product and the reliability of production.

[0093] The embodiment of the present application also proposes a processor for executing a program, which can specifically execute the relevant steps of the above-mentioned polishing method.

[0094] Specifically, the program may include program codes including computer operation instructions.

[0095] The processor may be a central processing unit CPU, or an application specific integrated circuit ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present application.

[0096] The embodiment of the present application also provides a computer storage medium on which a computer program is stored, and when the program is executed by a processor, any of the above-mentioned polishing methods is implemented.

[0097] The above-described method according to the embodiment of the present application may be implemented in hardware, firmware, or as software or computer code that can be stored in a recording medium (such as a CD ROM, RAM, floppy disk, hard disk, or magneto-optical disk), or as computer code that is originally stored in a remote recording medium or a non-transitory machine-readable medium downloaded via a network and will be stored in a local recording medium, so that the method described herein can be stored in such software processing on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware (such as an ASIC or FPGA). It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component (e.g., RAM, ROM, flash memory, etc.) that can store or receive software or computer code, and when the software or computer code is accessed and executed by a computer, a processor, or hardware, the polishing method described herein is implemented. In addition, when a general-purpose computer accesses the code for implementing the polishing method shown herein, the execution of the code converts the general-purpose computer into a dedicated computer for executing the polishing method shown herein.

[0098] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A polishing mechanism for pressing a wafer against a polishing pad for polishing, characterized in that: include: The support body is provided with at least two elongated through holes evenly distributed along the circumferential direction, and the axis of each of the elongated through holes passes through the center of the support body; At least two polishing heads are movably arranged in each of the long strip through holes in a one-to-one correspondence; The first driving mechanism is installed on the supporting body and connected with each of the polishing heads, and is used for driving each of the polishing heads to rotate and simultaneously reciprocate along the long strip through hole.

2. The polishing mechanism according to claim 1, characterized in that: Each polishing head maintains an equal distance from the center of the support body during the reciprocating movement along the long strip through hole.

3. The polishing mechanism according to claim 1, characterized in that: The first driving mechanism comprises: At least two motors, each of which is placed on a first side of the support body and has an output shaft passing through the support body and connected one-to-one with a rotating shaft of each of the polishing heads placed on a second side of the support body, and each of the motors is used to drive each of the polishing heads to rotate; The driving unit is installed on the supporting body and connected with the outer shell of each motor, and is used for driving each motor to move back and forth along the long strip through hole, thereby driving the polishing head to move back and forth along the long strip through hole.

4. The polishing mechanism according to claim 3, characterized in that: Both ends of the long strip through hole are semicircular to match the output shaft of the motor and / or the rotating shaft of the polishing head.

5. The polishing mechanism according to any one of claims 1 to 4, characterized in that: Also includes: The polishing liquid supply device is fixedly arranged in the central area of ​​the support body and is used for conveying the polishing liquid to the polishing pad.

6. The polishing mechanism according to claim 5, characterized in that: The polishing liquid supply device comprises: A circular polishing liquid tube is arranged in the central area of ​​the support body; At least two nozzles, each of which is connected to the outer side of the annular polishing liquid tube and is evenly distributed along the circumference, and each of the nozzles is arranged in a one-to-one correspondence with the area between adjacent polishing heads, and each of the nozzles is arranged at a preset angle to the moving direction of the polishing head on the support body.

7. The polishing mechanism according to claim 6, characterized in that: The preset angle is 15° to 45°.

8. The polishing mechanism according to any one of claims 1 to 4, characterized in that: The support body comprises: ontology; At least two connectors are connected to the main body and are evenly distributed along the circumference of the main body, and each of the connectors is provided with one of the long strip through holes, and the axis of each of the long strip through holes passes through the center of the main body.

9. A polishing module, characterized in that: include: A base, a polishing disc disposed on the base, a polishing pad disposed on the polishing disc, a second driving mechanism for controlling the rotation of the polishing disc, and a polishing mechanism according to any one of claims 1 to 8; wherein, The polishing pad has a surface facing the polishing mechanism with a plurality of annular grooves concentric with the polishing pad for containing polishing liquid. The polishing mechanism is placed above the polishing pad, and the supporting body of the polishing mechanism can be coaxially arranged with the polishing pad so that the axis of the elongated through hole on the supporting body is arranged along the radial direction of the annular groove, thereby enabling each of the polishing heads to reciprocate along the radial direction of the groove.

10. The polishing module according to claim 9, characterized in that: Also includes: A loading and unloading platform, arranged on the base and placed on one side of the polishing plate, for carrying wafers; The third driving mechanism is connected to the supporting body and is used to drive the supporting body to move between the polishing pad and the loading and unloading platform to receive the wafers to be polished from the loading and unloading platform, or transfer the polished wafers to the loading and unloading platform; the third driving mechanism is also used to drive the supporting body to rotate so that each of the polishing heads is placed above the loading and unloading platform in turn to exchange wafers with the loading and unloading platform.

11. A polishing method, characterized in that: The steps include: Controlling each polishing head on the support to load the wafer; Controlling each polishing head to move the wafer along the respective long strip through hole to an initial position; wherein each polishing head is at an equal distance from the center of the support body at the initial position; Control the support body to drive the polishing head to move above the polishing pad, and make the support body coaxial with the polishing pad, then control the support body to move toward the polishing pad, and make the polishing head press the wafer against the polishing pad; Controlling the polishing liquid supply device to deliver the polishing liquid to the polishing pad; Control the rotation of the polishing disc; Controlling each of the polishing heads to rotate and simultaneously reciprocate along the long strip through hole, and always keeping the distance between each polishing head and the center of the support body equal during the movement; After polishing is completed, each polishing head is controlled to unload the wafer.

12. The polishing method according to claim 11, characterized in that: The step of controlling each polishing head on the support body to load the wafer further comprises: Controlling the support body to move above the polishing pad, and then moving relative to the polishing pad toward the loading and unloading platform; The support body is controlled to rotate so that each of the polishing heads is placed above the loading and unloading platform in sequence, and wafers are loaded from the loading and unloading platform.

13. The polishing method according to claim 12, characterized in that: After the polishing is completed, the step of controlling each of the polishing heads to unload the wafer further includes: Controlling the support body to move relative to the polishing pad toward the loading and unloading platform; The support body is controlled to rotate so that each of the polishing heads is placed above the loading and unloading platform in sequence to unload the wafer onto the loading and unloading platform.

14. A processor, characterized in that: Relevant steps for performing the polishing method according to any one of claims 11 to 13.

15. A computer storage medium having a computer program stored thereon, wherein when the program is executed by a processor, the polishing method according to any one of claims 11 to 13 is implemented.

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