Wafer loading tool and grinding device

Abstract

The utility model provides a wafer loading tool and a grinding device, relates to the technical field of semiconductors, and aims to efficiently grind wafers. The wafer loading tool comprises a grinding head and a fixing ring. The grinding head comprises a grinding head end face, the fixing ring is connected with the grinding head end face, the fixing ring is connected with the edge position of the grinding head end face, at least one open groove is formed in the surface, away from the grinding head end face, of the fixing ring, and the open groove penetrates through the ring inner side and the ring outer side of the fixing ring. Grinding particles are arranged on the surface, close to the grinding pad, of the fixing ring, and a grinding pad trimmer is replaced. At least one open groove is formed in the surface, away from the end face of the grinding head, of the fixing ring, and the design that the open groove penetrates through the inner side and the outer side of the fixing ring guarantees that by-products generated in the grinding process can be discharged to the outer side of the fixing ring from the inner side of the fixing ring along with centrifugal force generated by rotation, and the grinding efficiency is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of semiconductor technology, and more particularly to a wafer loading tool and a grinding device. Background Art

[0002] With the rapid development of semiconductor technology, the integration density of semiconductor devices is getting higher and higher, and the precision requirements of integrated circuit manufacturing process are also getting higher and higher. Chemical mechanical polishing (CMP) is a key technology to achieve wafer surface flatness in the integrated circuit manufacturing process, and it is also a key technology to enable semiconductor devices to have a higher degree of integration in the entire integrated circuit manufacturing process.

[0003] In CMP, a grinding device is required to grind and polish the wafer. The grinding device usually includes a grinding head, a fixed ring, a grinding pad, a grinding slurry dispenser, and a grinding pad dresser. During the wafer grinding process, the grinding slurry dispenser will deliver polishing liquid to the grinding pad. The grinding particles and some chemical additives in the polishing liquid can improve the grinding efficiency of the wafer. The grinding pad dresser is used to polish the grinding pad to ensure that the roughness of the grinding pad can keep the wafer in a high-efficiency working state during the grinding process.

[0004] However, the grinding pad dresser and the grinding head may collide during the grinding process, causing damage to the wafer. In addition, since the wafer is confined in the cavity composed of the grinding head, the fixed ring and the grinding pad, the by-products produced during the grinding process cannot be discharged in time, and fresh grinding fluid from the outside is difficult to enter, so the grinding efficiency is low. Utility Model Content

[0005] The embodiments of the present application provide a wafer loading device and a grinding device, which are intended to improve the grinding efficiency of the wafer and prevent the occurrence of collisions between a grinding pad dresser and a grinding head during the grinding process.

[0006] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0007] In a first aspect, a wafer loading device is provided. The wafer loading device comprises: a grinding head and a fixing ring. The grinding head comprises a grinding head end face, the fixing ring is connected to the edge of the grinding head end face, and the surface of the fixing ring away from the grinding head end face is provided with at least one groove, and the groove passes through the inner side and the outer side of the fixing ring. Abrasive particles are provided on the surface of the fixing ring close to the grinding pad.

[0008] The wafer loading device provided by the present application comprises a grinding head and a fixed ring, wherein the grinding head comprises a grinding head end face, and the fixed ring in the wafer loading device is connected to the edge position of the grinding head end face, thereby ensuring that the wafer is limited in the accommodation space formed by the grinding head end face, the fixed ring and the grinding pad, and the position displacement will not occur due to the rotation of the grinding head and the grinding pad during the grinding process, thereby ensuring the uniformity of the grinding process. At least one slot is arranged on the surface of the fixed ring away from the grinding head end face, and the slot is designed to pass through the inner side and the outer side of the fixed ring, thereby ensuring that the by-products generated during the grinding process can be discharged from the inner side of the fixed ring to the outer side of the fixed ring with the centrifugal force generated by the rotation, and also enabling the fresh grinding liquid on the outer side of the ring to flow into the inner side of the ring more conveniently through the slot, thereby improving the grinding efficiency. And since abrasive particles are arranged on the surface of the fixed ring close to the grinding pad, when the wafer is ground on the grinding pad, the abrasive particles on the surface of the fixed ring close to the grinding pad will also grind the grinding pad synchronously, thereby ensuring that the roughness of the grinding pad can enable the wafer to maintain a high-efficiency working state during the grinding process. Furthermore, since the surface of the fixed ring close to the grinding pad has grinding particles, the function of a grinding pad dresser can be realized, so a grinding pad dresser is no longer needed in the grinding device, thereby preventing the grinding pad dresser from colliding with the grinding head during the grinding process.

[0009] As a possible implementation manner, the abrasive particles include diamond particles or ceramic particles.

[0010] As a possible implementation manner, an extending direction of the slot has an angle with a width direction of the fixing ring at the slot position, and the extending direction of the slot is a direction from the inner side of the fixing ring to the outer side of the ring.

[0011] As a possible implementation, the fixing ring rotates in a clockwise direction. In a counterclockwise direction, the angle between the extension direction of the slot and the width direction of the fixing ring at the slot position is greater than 90° and less than 180°. Alternatively, the fixing ring rotates in a counterclockwise direction. In a counterclockwise direction, the angle between the extension direction of the slot and the width direction of the fixing ring at the slot position is greater than 0° and less than 90°.

[0012] As a possible implementation manner, the ratio of the groove depth to the thickness of the fixing ring is in the range of 0.3 to 0.5.

[0013] As a possible implementation manner, the grooves include at least one of long straight grooves, wavy grooves, and broken line grooves.

[0014] As a possible implementation manner, a plurality of slots are provided on the fixing ring, and the plurality of slots are evenly distributed.

[0015] As a possible implementation manner, the number of abrasive particles arranged between two adjacent slots is a fixed value, and the arrangement manner is consistent.

[0016] As a possible implementation, the grinding head includes a pressure regulating cavity and a fixed structure, and the fixed structure is arranged on the periphery of the pressure regulating cavity. The fixed ring is connected to the fixed structure. The surface of the pressure regulating cavity and the fixed structure close to the grinding pad constitutes the end face of the grinding head. At least one airbag and a gas channel connected to the airbag are arranged inside the pressure regulating cavity. The airbag is close to the grinding pad relative to the gas channel. The bottom of the airbag is connected to the end face of the grinding head. The wafer loader also includes a loader film, and the loader film is attached to the end face of the grinding head.

[0017] As a possible implementation manner, the surface of the pressure regulating cavity close to the grinding pad has an opening, and the opening is opposite to the position of the airbag.

[0018] As a possible implementation, a central airbag and at least one annular airbag are arranged inside the pressure regulating cavity, and the at least one annular airbag is sequentially arranged around the periphery of the central airbag.

[0019] As a possible implementation, a central airbag, a first annular airbag and a second annular airbag are arranged inside the pressure regulating cavity. The central airbag is located in the central area of ​​the pressure regulating cavity, the second annular airbag is located outside the central airbag, and the first annular airbag is located outside the second annular airbag.

[0020] In a second aspect, a grinding device is provided, comprising a rotating shaft, a grinding table, a grinding pad, and a wafer loader as mentioned in the first aspect and possible implementations thereof, wherein the wafer loader is arranged on one side of the grinding pad.

[0021] It can be understood that the beneficial effects that can be achieved in the second aspect can refer to the beneficial effects of the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the present application, the following briefly introduces the drawings required to be used in some embodiments of the present application. Obviously, the drawings described below are only drawings of some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the products involved in the embodiments of the present application, the actual process of the method, the actual timing of the signal, etc.

[0023] Figure 1 A schematic diagram of the composition of a grinding device provided in an embodiment of the present application;

[0024] Figure 2A top view of a grinding device provided in an embodiment of the present application;

[0025] Figure 3 A schematic diagram of a wafer loading device provided in an embodiment of the present application;

[0026] Figure 4 A schematic diagram of the structure of a fixing ring provided in an embodiment of the present application;

[0027] Figure 5A A schematic diagram of the structure of another fixing ring provided in an embodiment of the present application;

[0028] Figure 5B A schematic diagram of the structure of another fixing ring provided in an embodiment of the present application;

[0029] Figure 5C A schematic diagram of the structure of another fixing ring provided in an embodiment of the present application;

[0030] Figure 5D A schematic diagram of the structure of another fixing ring provided in an embodiment of the present application;

[0031] Figure 6 A schematic diagram of a fixing ring provided in an embodiment of the present application;

[0032] Figure 7 A schematic structural diagram of a wafer loading device provided in an embodiment of the present application;

[0033] Figure 8 A schematic diagram of the structure of another wafer loading device provided in an embodiment of the present application;

[0034] Fig. 9 A schematic diagram of a grinding device provided in an embodiment of the present application;

[0035] Fig.10 A schematic diagram of another grinding device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0036] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments provided by the present application, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present application.

[0037] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying 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 the context requires otherwise, throughout the specification and claims, the term "including" is to be interpreted as an open, inclusive meaning, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "exemplarily" or "some examples" and the like are intended to indicate that specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present application. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics described may be included in any one or more embodiments or examples in any appropriate manner.

[0039] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, unless otherwise specified, "plurality" means two or more.

[0040] When describing some embodiments, the term "connected" and its derivative expressions may be used. For example, when describing some embodiments, the term "connected" may be used to indicate that two or more components are in direct physical or electrical contact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this document.

[0041] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of variation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0042] In the context of this application, the meaning of "on", "above", and "over" should be interpreted in the broadest manner, so that "on" not only means "directly on something", but also includes the meaning of "on something" with intervening features or layers in between, and "above" or "over" not only means "above" or "over" something, but also includes the meaning of "above" or "over" something without intervening features or layers in between (i.e., directly on something).

[0043] With the rapid development of semiconductor technology, the size of semiconductor devices is getting smaller and smaller, and the integration density of semiconductor devices is getting higher and higher, so the precision requirements for integrated circuit manufacturing processes are also getting higher and higher. Since the optical system is limited by the depth of field conditions, it is difficult to use photolithography technology on a rough surface to achieve high resolution for tiny graphics, and the rough dielectric surface will cause metallization problems, so wafer flattening technology has emerged.

[0044] Wafer planarization refers to changing the morphology of the wafer surface, making the wafer smoother from rough, or flatter from uneven. As the size of semiconductor devices becomes smaller and smaller, the resolution requirements of lithography technology are getting higher and higher. Ordinary wafer planarization technologies such as heated flow planarization can no longer meet the high precision requirements of integrated circuit manufacturing processes. Chemical mechanical polishing (CMP) has become a key technology in wafer planarization.

[0045] In CMP, a grinding device is usually used to grind and polish the wafer, for example, Figure 1 As shown, Figure 1 The composition of a grinding device is shown. Figure 1 The grinding equipment includes a grinding head 1, a fixed ring 2, a grinding pad dresser 3, a grinding pad 4, a grinding table 5 and a rotating shaft 6, wherein the grinding head 1 and the fixed ring 2 constitute a wafer loader 10, and the wafer 7 is confined in the space formed by the grinding head 1, the fixed ring 2 and the grinding pad 4.

[0046] The rotating shaft 6 is connected to the grinding table 5, and the grinding table 5 is provided with a grinding pad 4, which is composed of a porous and elastic polymer material. The grinding pad dresser 3 and the wafer carrier 10 are arranged on one side of the grinding pad 4. Since the rotating shaft 6 rotates at a certain speed during the wafer flattening process, it will drive the rotation of the grinding table 5, and then drive the rotation of the grinding pad 4 on the grinding table 5. The grinding head 1 will also rotate at a certain speed during the wafer flattening process and will apply pressure downward, so the wafer carrier 10 can press the wafer 7 on the rough grinding pad 4 with a certain pressure for grinding.

[0047] For example, Figure 2 As shown, Figure 2 A top view of the grinding apparatus is shown. Figure 1 and Figure 2 , the description of the wafer flattening process in the grinding equipment is as follows:

[0048] The grinding pad 4 rotates at a certain speed driven by the rotating shaft 6, and the wafer 7 also rotates at a certain speed driven by the grinding head 1. At the same time, the wafer 7 also moves horizontally at a certain speed driven by the grinding head 1. Figure 2 As shown in FIG, the wafer 7 moves from position B to position B' while rotating and grinding on the grinding pad 4 in a counterclockwise direction. The grinding pad dresser 3 performs periodic swings on the grinding pad 4. For example, when the wafer 7 moves from position B to position B', the grinding pad dresser 3 moves from position A' to position A.

[0049] During the wafer grinding process, the grinding slurry distributor 8 will deliver polishing liquid to the grinding pad 4. The grinding particles and some chemical additives in the polishing liquid can improve the grinding efficiency of the wafer. The flattening process of the wafer 7 is the process of the wafer 7 being continuously ground on the rough grinding pad 4 with the polishing liquid. During the process of the wafer 7 being polished smooth, the surface of the grinding pad 4 in contact with the wafer 7 will gradually become smooth from rough, and the grinding efficiency will deteriorate. However, since diamond particles are arranged on the grinding pad dresser 3, and the grinding pad dresser 3 is periodically swung on the grinding pad 4, the swinging area covers the surface of the grinding pad 4 in contact with the wafer 7, so the grinding pad dresser 3 can make the grinding pad 4 smooth due to the grinding of the wafer 7 become rough again, thereby improving the grinding efficiency.

[0050] However, since the wafer is confined in the cavity formed by the grinding head, the fixed ring and the grinding pad, it is difficult for fresh grinding fluid from the outside to enter, and the by-products produced during the grinding process will also accumulate in the cavity formed by the grinding head, the fixed ring and the grinding pad, and cannot be discharged in time, which will cause the grinding pad to smooth faster and reduce the grinding efficiency. In severe cases, the particles produced by the by-products may scratch the wafer and cause serious defects. In addition, since the grinding pad dresser oscillates periodically on the grinding pad, the grinding pad dresser may collide with the grinding head, and once the grinding pad dresser collides with the grinding head, it is easy to cause damage to the wafer.

[0051] In view of this, an embodiment of the present application provides a wafer loading tool, such as Figure 3As shown, the wafer loading device 10 includes: a grinding head 1 and a fixing ring 2. The grinding head 1 includes a grinding head end face 11, and the grinding head end face 11 is close to the grinding pad 4. The fixing ring 2 is connected to the grinding head end face 11, and the fixing ring 2 is connected to the edge of the grinding head end face 11, and the orthographic projection of the fixing ring 2 on the grinding head end face 11 is located at the edge of the grinding head end face 11. The grinding head 1 includes a grinding head end face 11, and the orthographic projection of the fixing ring 2 in the wafer loading device 10 on the grinding head end face 11 is located at the edge of the grinding head end face 11, which ensures that the wafer is limited in the accommodation space formed by the grinding head end face 11, the fixing ring 2 and the grinding pad 4, and will not be shifted due to the rotation of the grinding head 1 and the grinding pad 4 during the grinding process, thereby ensuring the uniformity of the grinding process.

[0052] Abrasive particles 22 are arranged on the surface of the fixed ring 2 near the grinding pad 4. As a possible implementation method, the abrasive particles 22 include diamond particles or ceramic particles. When the wafer is ground on the grinding pad 4, the abrasive particles 22 on the fixed ring 2 will also grind the grinding pad 4, maintaining the roughness of the grinding pad 4, so that the wafer can always maintain high efficiency in the CMP process. And because the design of the abrasive particles on the surface of the fixed ring near the grinding pad can realize the function of the grinding pad dresser, the grinding pad dresser is no longer needed in the grinding device, preventing the grinding pad dresser and the grinding head from colliding during the grinding process.

[0053] Further, such as Figure 4 As shown, Figure 4 The structure of the fixing ring is shown in FIG. Figure 4 The surface of the fixing ring 2 away from the end face 11 of the grinding head is provided with at least one slot 21, and the slot 21 passes through the inner side and the outer side of the fixing ring. Figure 4 As shown in the figure, it is a circular ring structure. Figure 4 It can be seen as consisting of two concentric circles, the outer circle is the outer side of the fixed ring 2, and the inner circle is the inner side of the fixed ring 2. The grooves 21 that penetrate the inner and outer sides of the fixed ring ensure that the by-products generated during the grinding process can be discharged from the inner side of the fixed ring to the outer side of the fixed ring with the centrifugal force generated by the rotation, and can also make the fresh grinding fluid on the outer side of the ring flow into the inner side of the ring more conveniently through the grooves, thereby improving the grinding efficiency. It should be noted that the present application Figure 4 Only 8 slots are used as an example for illustration. In actual application scenarios, there may be more or less slots.

[0054] As a possible implementation, Figure 5A As shown, there is an angle between the extending direction of the slot 21 and the width direction of the fixing ring 2 at the position of the slot 21. Figure 5A, the extending direction of the slot 21 is from the inner side of the fixing ring 2 to the outer side, that is, the L1 direction where the arrow is located, and the width direction of the slot 21 is the direction of the line connecting the reference point and the center of the fixing ring, with a certain point in the position of the slot on the inner side of the fixing ring as the reference point. That is, the direction indicated by the double arrow R1-R2, where R1 is the radius of the outer circle of the fixing ring 2, and R2 is the radius of the inner circle. According to Figure 5A It can be seen that there is an angle α between the extension direction of the slot 21 and the width direction of the fixing ring 2 at the slot 21. This beveled slot setting can better utilize centrifugal force during wafer grinding, that is, during rotation, to discharge by-products generated during the grinding process.

[0055] Reference Figure 5A In some examples, during the wafer grinding process, the grinding head rotates counterclockwise at a certain rate relative to the grinding pad. Since the fixing ring 2 is connected to the edge of the end face of the grinding head, the fixing ring 2 also rotates counterclockwise at a certain rate relative to the grinding pad. In this case, in the counterclockwise direction, the angle between the extension direction of the slot and the width direction of the slot position where the fixing ring is located is greater than 0° and less than 90°.

[0056] according to Figure 5A It can be seen that the ray in the extension direction of the slot is taken as the starting edge, that is, the ray in the direction of arrow L1 is taken as the starting edge, and the straight line in the width direction of the slot is taken as the terminal edge, that is, the straight line in the direction of the double arrow R1-R2 is taken as the terminal edge, in the counterclockwise direction, that is Figure 5A In the direction of the arrow shown above α, the angle from the starting edge to the ending edge is α. Depending on the reference point selected for the position of the slot on the inner side of the fixed ring, the size of α will increase or decrease accordingly, but it is always greater than 0° and less than 90°. This setting method allows the fixed ring to rotate counterclockwise at a certain speed relative to the grinding pad, and the by-products produced during the grinding process can follow the counterclockwise rotation trend and be discharged more easily, thereby further improving the grinding efficiency.

[0057] Reference Figure 5B In other examples, during the wafer grinding process, the grinding head rotates clockwise at a certain rate relative to the grinding pad. Since the fixing ring 2 is connected to the edge of the end face of the grinding head, the fixing ring 2 also rotates clockwise at a certain rate relative to the grinding pad. In this case, along the clockwise direction, the angle between the extension direction of the slot and the width direction of the slot position where the fixing ring is located is greater than 0° and less than 90°.

[0058] according to Figure 5BIt can be seen that the ray in the extension direction of the slot is taken as the starting edge, that is, the ray in the direction of arrow L1 is taken as the starting edge, and the straight line in the width direction of the slot is taken as the terminal edge, that is, the straight line in the direction of the double arrow R1-R2 is taken as the terminal edge, in the counterclockwise direction, that is Figure 5B In the direction of the arrow shown above α, the angle from the starting edge to the ending edge is α. Depending on the reference point selected for the position of the slot on the inner side of the fixed ring, the size of α will increase or decrease accordingly, but it is always greater than 90° and less than 180°. This setting method allows the fixed ring to rotate clockwise at a certain speed relative to the grinding pad, and the by-products produced during the grinding process can follow the clockwise rotation trend and be discharged more easily, thereby further improving the grinding efficiency.

[0059] Figure 5A and Figure 5B The slots in the embodiment are all long straight slots, for example, Figure 5C As shown, the shape of the slot is wavy. Figure 5D It should be understood that the embodiment of the present application does not limit the shape of the grooves, and the main difference between the grooves of different shapes is the discharge efficiency of grinding byproducts and the entry efficiency of grinding liquid.

[0060] Combination Figure 4 , Figure 5A as well as Figure 5B It should be understood that the fixed ring is provided with a plurality of slots, and the plurality of slots are evenly distributed. Even distribution means that the intervals between two adjacent slots are equal. Since the wafer loader is moving on the grinding pad and the wafer is constantly rotating during the grinding process, the position of the by-products generated during the grinding process of the wafer is not fixed. If only a single slot is provided on the fixed ring, or the slots are unevenly provided, more by-products will be present at certain positions of the slots of the fixed ring, which will not be discharged to the outside of the fixed ring in time, which will reduce the efficiency and may also cause scratches on the wafer.

[0061] In some embodiments, Figure 6 6 shows a fixing ring provided in an embodiment of the present application. Figure 6 , the number of abrasive particles set between two adjacent slots is a fixed value, and the arrangement is consistent, for example Figure 6The number of abrasive particles set between two adjacent slots on the fixed ring shown in the figure is 3 and they are all arranged horizontally in a certain direction. The number of abrasive particles set between two adjacent slots is set to a fixed value, so that within a certain range, there are always the same number of abrasive particles to grind the grinding pad, which ensures the uniformity of the grinding pad process, makes the roughness of the grinding pad roughly the same, further ensures the uniformity of the wafer grinding on the grinding pad, and improves efficiency. It should be noted that this application does not limit the number of abrasive particles. Figure 6 The numbers of abrasive particles shown are for illustration only.

[0062] Reference Figure 6 As a possible implementation, the ratio of the depth h2 of the slot 21 to the thickness h1 of the fixing ring 2 is in the range of 0.3 to 0.5.

[0063] In some embodiments, Figure 7 As shown, Figure 7 Another structure of a wafer loader is shown. Figure 7 As shown, the grinding head includes a pressure regulating cavity 12 and a fixed structure 13, and the fixed structure 13 is arranged on the periphery of the pressure regulating cavity 12. The fixing ring 2 is connected to the fixed structure 13. The surfaces of the pressure regulating cavity 12 and the fixed structure 13 close to the grinding pad 4 constitute the grinding head end face 11. At least one airbag 121 and a gas channel 122 connected to the airbag 121 are arranged inside the pressure regulating cavity 12. The airbag 121 is close to the grinding pad 4 relative to the gas channel 122. The bottom of the airbag 121 is connected to the grinding head end face 11. The wafer loader also includes a loader film 9, which is attached to the grinding head end face 11.

[0064] Figure 7 In the example, only one air bag is provided inside the pressure regulating cavity 12. Figure 7 , an airbag 121 and a gas channel 122 connected to the airbag 121 are provided inside the pressure regulating chamber 12. During the wafer grinding process, gas, such as nitrogen, is filled into or sucked out of the airbag 121 through the gas channel 122. When the gas channel 122 fills gas into the airbag 121, the airbag 121 expands and presses against the end face of the grinding head. The end face 11 of the grinding head will receive a greater pressure, and then the wafer 7 will be pressed against the grinding pad 4 with a greater pressure, thereby intensifying the friction of the wafer 7 on the rough grinding pad. In this case, a large area of ​​the wafer 7 is pressed on the grinding pad 4 for grinding. When the smoothness of the wafer 7 is basically met, the operator can control the flow rate and flow velocity of the gas filled into the gas channel 122 to shrink the airbag 121, reduce the pressure on the end face 11 of the grinding head, and then reduce the pressure received by the wafer 7. In this case, a small area of ​​the wafer 7 is pressed on the grinding pad 4 for grinding.

[0065] The purpose of the loading jig film 9 is to support the wafer 7. If the loading jig film 9 is not used as a buffer and the grinding head is allowed to press directly on the wafer, the downward pressure of the grinding head is likely to damage the wafer. The elastic loading jig film 9 will adjust the back of the wafer 7, and the downward pressure of the grinding head will be evenly applied to the wafer 7 through the loading jig film 9. In addition, the loading jig film 9 can also offset the deformation of the wafer 7, such as the bending or deformation of the wafer 7 caused by film or thermal stress, thereby improving the uniformity of the CMP process.

[0066] In other embodiments, Figure 8 As shown, a central airbag 1211 and at least one annular airbag 1212 are arranged inside the pressure regulating chamber 11. At least one annular airbag 1212 is arranged in turn around the periphery of the central airbag 1211. Figure 8 , Figure 8 Take the example of a central airbag 1211 and two annular airbags 1212 disposed inside the pressure regulating chamber 11, wherein the two annular airbags 1212 are respectively recorded as a first annular airbag a and a second annular airbag b. The gas channel connected to the first annular airbag a is recorded as a first gas channel 122a, the gas channel connected to the second annular airbag b is recorded as a second gas channel 122b, and the gas channel connected to the central airbag 1211 is recorded as a third gas channel 122c. Figure 8 “˜122 ” after the first gas channel 122 a , the second gas channel 122 b , and the third gas channel 122 c in FIG. 1 means that they all belong to the gas channel 122 .

[0067] The third gas channel 122c can inflate or inhale the central airbag 1211, the second gas channel 122b can inflate or inhale the second annular airbag b, and the first gas channel 122a can inflate or inhale the first annular airbag a. By setting up multiple airbags, more precise control can be achieved on different areas of the wafer 7. The first annular airbag a can control the projection on the wafer to be located in the edge area, so the pressure in the edge area of ​​the wafer can be controlled. The projection of the second annular airbag b on the wafer is located in the middle area, so the pressure in the middle area of ​​the wafer can be controlled. The projection of the central airbag on the wafer is located in the core area, so the pressure in the core area of ​​the wafer can be controlled.

[0068] For example, during the grinding process, the center area of ​​wafer 7 has met the smoothness requirement, but the edge of wafer 7 has not met the smoothness requirement. Therefore, it is necessary to focus on grinding the edge of wafer 7. Through the wafer loading device provided in the embodiment of the present application, the operator can achieve this by increasing the gas delivery method on the first gas channel. Due to the increase in the flow rate and flow velocity of the gas delivered on the first gas channel, the first annular airbag a will expand more than the second annular airbag b and the center airbag 1211, and the pressure on the edge area of ​​the grinding head end face 11 will increase. The pressure applied to the edge of wafer 7 after passing through the loading device membrane 9 will be greater than the pressure applied to the center of wafer 7. Therefore, the edge of wafer 7 will be ground more fully.

[0069] By setting up multiple airbags and corresponding gas channels inside the pressure regulating chamber, the operator can control the pressure of the airbag corresponding to the gas channel on the wafer projection area by controlling the gas flow and flow rate to the gas channel. This avoids the problem that in the actual grinding process, when there is only one pressure partition, that is, one airbag, different areas of the wafer cannot be adjusted in a targeted manner due to the influence of the rotation speed, uneven distribution of the grinding liquid, etc., and realizes the individual control of the pressure of each area of ​​the wafer. It can increase or decrease the pressure for the area with a lower or higher grinding rate according to the grinding results of the wafer, thereby achieving better grinding uniformity and better grinding adjustment effect.

[0070] As a possible implementation, Figure 8 As shown, the surface of the pressure regulating chamber close to the grinding pad 4 has an opening 111, and the opening 111 is opposite to the airbag. In the grinding preparation stage, the opening 111 and the gas channel are used to evacuate the gas between the carrier film 9 and the wafer 7 to create a vacuum environment, and the vacuum negative pressure is used to make the wafer 7 better adsorbed on the surface of the wafer carrier close to the grinding pad 4.

[0071] The present application also provides a grinding device, for example, Fig. 9 See Fig. 9 The grinding device 100 includes a rotating shaft 6, a grinding table 5, a grinding pad 4, a grinding pad dresser 3, and a wafer carrier 10 as mentioned in the above-mentioned manner, wherein there are no grinding particles on the fixing ring of the wafer carrier 10, and the wafer carrier 10 is arranged on one side of the grinding pad 4. The embodiment of the present application also provides a grinding device, exemplarily, as Fig.10 See Fig.10The grinding device 100 includes a rotating shaft 6, a grinding table 5, a grinding pad 4, and a wafer carrier 10 as mentioned in the above-mentioned manner, wherein abrasive particles 22 are arranged on a fixed ring in the wafer carrier 10, and the wafer carrier 10 is arranged on one side of the grinding pad 4. Since the abrasive particles 22 are arranged on the fixed ring 2, when the wafer is ground on the grinding pad, the abrasive particles on the fixed ring will also grind the grinding pad to maintain the roughness of the grinding pad, so it is no longer necessary to set a grinding pad dresser, so as to avoid the collision between the grinding pad dresser and the wafer carrier during the wafer grinding process, thereby saving costs.

[0072] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the utility model should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model shall be based on the protection scope of the claims.

Claims

1. A wafer loading device, characterized in that: include: A grinding head, the grinding head comprising a grinding head end surface; A fixing ring connected to the edge of the end surface of the grinding head; The surface of the fixing ring away from the end surface of the grinding head is provided with at least one groove, and the groove passes through the inner side and the outer side of the fixing ring; The surface of the fixing ring close to the grinding pad is provided with a plurality of grinding particles; The fixing ring rotates in a clockwise direction; in a counterclockwise direction, the angle between the extending direction of the slot and the width direction of the fixing ring at the slot position is greater than 90° and less than 180°; Alternatively, the fixing ring rotates in a counterclockwise direction; in the counterclockwise direction, an angle between an extension direction of the slot and a width direction of the fixing ring at the slot position is greater than 0° and less than 90°.

2. The wafer loading device according to claim 1, characterized in that: The abrasive particles include diamond particles or ceramic particles.

3. The wafer loading device according to claim 1 or 2, characterized in that: An extending direction of the slot has an angle with a width direction of the fixing ring at the slot position; and the extending direction of the slot is a direction from the inner side of the fixing ring to the outer side of the ring.

4. The wafer loading device according to claim 1 or 2, characterized in that: The ratio of the depth of the groove to the thickness of the fixing ring is in the range of 0.3 to 0.

5.

5. The wafer loading tool according to claim 1 or 2, characterized in that: The grooves include at least one of long straight grooves, wavy grooves, and broken line grooves.

6. The wafer loading device according to claim 1 or 2, characterized in that: The fixing ring is provided with a plurality of slots, and the plurality of slots are evenly distributed.

7. The wafer loading device according to claim 6, characterized in that: The number of abrasive particles arranged between two adjacent slots is a fixed value, and the arrangement is consistent.

8. The wafer loading device according to claim 1 or 2, characterized in that: The grinding head comprises a pressure regulating cavity and a fixing structure, wherein the fixing structure is arranged at the periphery of the pressure regulating cavity; the fixing ring is connected to the fixing structure; the surfaces of the pressure regulating cavity and the fixing structure close to the grinding pad constitute the end surface of the grinding head; At least one air bag and a gas passage connected to the air bag are arranged inside the pressure regulating cavity; the air bag is close to the polishing pad relative to the gas passage; The bottom of the air bag is connected to the end surface of the grinding head; The wafer loading tool further comprises a loading tool film, and the loading tool film is attached to the end surface of the grinding head.

9. The wafer loading tool according to claim 8, characterized in that: The surface of the pressure regulating cavity close to the grinding pad has an opening, and the opening is opposite to the airbag.

10. The wafer loading device according to claim 8, characterized in that: The pressure regulating cavity is provided with a central airbag and at least one annular airbag: The at least one annular airbag is sequentially arranged on the periphery of the central airbag.

11. The wafer loading tool according to claim 8, characterized in that: The pressure regulating cavity is provided with a central airbag, a first annular airbag and a second annular airbag: The central airbag is located in the central area of ​​the pressure regulating cavity, the second annular airbag is located outside the central airbag, and the first annular airbag is located outside the second annular airbag.

12. A grinding device, characterized in that: The grinding device comprises: Rotating shaft; A grinding table, the grinding table is connected to the rotating shaft; A grinding pad, wherein the grinding pad is arranged on the grinding table; And the wafer carrier according to any one of claims 1 to 11, wherein the wafer carrier is arranged on the polishing pad.

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