Grinding pad trimmer and chemical mechanical grinding equipment

Abstract

The invention discloses a polishing pad trimmer and chemical mechanical polishing equipment, the polishing pad trimmer comprises a base, a swing arm, a trimming head, a trimming wheel and a bijection sensor, one end of the swing arm is connected with the base, the other end of the swing arm can swing back and forth in the horizontal direction, the trimming head is connected with the other end of the swing arm, and the trimming wheel is connected with the bijection sensor. The finishing head can rotate; the dressing wheel is arranged below the dressing head, and the dressing wheel is driven by the dressing head to rotate; the correlation sensor comprises an emitter and a receiver, the emitter and the receiver are arranged at the same horizontal height as the dressing wheel, and the dressing wheel is located on a connecting line between the emitter and the receiver. Whether the dressing wheel is installed below the dressing head or not can be monitored, and the situation that in the prior art, when the dressing wheel is not installed on a dresser, a table can conduct grinding is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor equipment, and in particular to a polishing pad dresser and a chemical mechanical polishing device. Background Art

[0002] CMP, or Chemical Mechanical Polishing, is the nanoscale global flattening surface manufacturing process with the highest output efficiency, the most mature technology and the most widespread application in integrated circuit manufacturing. In the manufacturing process of semiconductor chips, especially in the single crystal silicon wafer manufacturing process and the first half of the process, CMP technology is used many times to achieve the necessary surface flatness.

[0003] The main equipment of chemical mechanical polishing generally includes: a grinding table (Platen), a polishing pad (Polishing Pad), a polishing head (Head) and a slurry dispenser (Slurry Dispenser). The silicon wafer is fixed at the bottom of the polishing head, and the polishing pad is placed on the grinding table. During grinding, the rotating polishing head presses on the rotating polishing pad with a certain pressure. The slurry dispenser is used to add flowing polishing liquid to the polishing pad. The polishing liquid is evenly distributed on it under the transmission of the polishing pad and the action of centrifugal force, forming a layer of polishing liquid film between the silicon wafer and the polishing pad. The chemical components in the polishing liquid react chemically with the surface material of the silicon wafer, converting insoluble substances into easily soluble substances, or softening substances with high hardness, and then these chemical reactants are removed from the surface of the silicon wafer through the micromechanical friction of the abrasive particles and dissolved into the flowing liquid and taken away.

[0004] The polishing pad is usually covered with several annular grooves, which are conducive to conveying the polishing liquid and delivering the abrasive particles in the polishing liquid to the surface of the silicon wafer to remove byproducts. In use, after the polishing pad has polished several silicon wafers, the grooves are filled with abrasive particles and debris aggregates, so that the original rough surface of the polishing pad is glazed (Glazing) to form a glazed layer, and the ability of the polishing pad to retain the polishing liquid is reduced, and the polishing rate is reduced accordingly, and the surface of the silicon wafer may also be scratched. Therefore, the surface of the polishing pad needs to be trimmed regularly using a pad conditioner to restore the surface of the polishing pad to a rough state, extend the service life of the polishing pad, and avoid the need to replace a new polishing pad to achieve the purpose of mass production and cost savings.

[0005] However, during the maintenance of existing chemical mechanical polishing equipment, it is inevitable that engineers will forget to install a new dressing wheel after removing the dressing wheel (Disk) that needs to be replaced in the dresser. In addition, the machine will perform normal grinding without a dressing wheel installed, which may cause scratches on the surface of the silicon wafer. In order to prevent this from happening, it is necessary to propose a new polishing pad dresser and chemical mechanical polishing equipment. Summary of the invention

[0006] The object of the present invention is to provide a polishing pad dresser and a chemical mechanical polishing device. By arranging a pair of transmitting sensors at the same level as the dressing wheel and making the dressing wheel located on the line between the transmitter and the receiver, it is possible to monitor whether a dressing wheel is installed under the dressing head, thereby avoiding the situation in the prior art where the table will also perform grinding when the dressing wheel (Disk) is not installed on the dresser.

[0007] To achieve the above object, in a first aspect, the present invention provides a polishing pad conditioner, comprising:

[0008] Pedestal;

[0009] A swing arm, one end of which is connected to the base, and the other end of which is capable of swinging back and forth in a horizontal direction;

[0010] A trimming head, the trimming head is connected to the other end of the swing arm, and the trimming head is rotatable;

[0011] A dressing wheel, which is arranged below the dressing head and rotates under the drive of the dressing head;

[0012] The through-beam sensor comprises a transmitter and a receiver, wherein the transmitter and the receiver are arranged at the same level as the trimming wheel, and the trimming wheel is located on a line between the transmitter and the receiver.

[0013] Optionally, at least two threaded holes are provided on the trimming head, at least two through holes are provided at corresponding positions on the trimming wheel, and at least two screws pass through at least two through holes to fix the trimming wheel below the trimming head.

[0014] Optionally, the transmitter is arranged on a side of the base facing the dressing wheel, and the receiver is arranged on a side of the dressing wheel facing away from the transmitter, and the position is fixed.

[0015] Optionally, the receiver is arranged on a side of the base facing the dressing wheel, and the transmitter is arranged on a side of the dressing wheel facing away from the receiver, and the position is fixed.

[0016] Optionally, the distance between the transmitter and the dressing wheel is not greater than the length of the swing arm.

[0017] Optionally, the distance between the receiver and the dressing wheel is not greater than the length of the swing arm.

[0018] Optionally, a surface of the dressing wheel facing away from the dressing head is provided with diamonds.

[0019] In a second aspect, the present invention provides a chemical mechanical polishing device, comprising:

[0020] A grinding table, wherein a grinding pad is arranged on the grinding table, and a plurality of annular grooves are arranged on the upper surface of the grinding pad;

[0021] A grinding head, wherein the grinding head is disposed above the grinding pad, and a surface opposite to the grinding pad is used for adsorbing the silicon wafer;

[0022] A grinding liquid supplier, the grinding liquid supplier is arranged above the grinding pad and is used to provide grinding liquid during the grinding process;

[0023] Any of the above-mentioned polishing pad dressers is used to regularly dress the upper surface of the polishing pad.

[0024] Compared with the prior art, the technical solution of the present invention has at least the following beneficial effects:

[0025] The grinding pad dresser provided by the present invention includes a base, a swing arm, a dresser head, a dresser wheel and a cross-beam sensor, one end of the swing arm is connected to the base, the other end of the swing arm can swing back and forth in the horizontal direction, the dresser head is connected to the other end of the swing arm, and the dresser head can rotate; the dresser wheel is arranged below the dresser head, and the dresser wheel rotates under the drive of the dresser head; the cross-beam sensor includes a transmitter and a receiver, the transmitter and the receiver are arranged at the same level as the dresser wheel, and the dresser wheel is located on the line between the transmitter and the receiver. When the dresser wheel is installed, the laser emitted by the transmitter is blocked by the dresser wheel, and the receiver cannot receive the laser emitted by the transmitter. When the dresser wheel is not installed, the laser emitted by the transmitter directly irradiates the receiver, triggering an alarm, and can monitor whether the dresser wheel is installed below the dresser head, thereby avoiding the situation in the prior art that the machine platform will also grind when the dresser wheel is not installed.

[0026] The chemical mechanical polishing equipment provided by the present invention includes the polishing pad dresser provided by the present invention, which can monitor whether the dressing wheel is installed under the dressing head, thereby avoiding the situation in the prior art where the machine platform will also perform grinding when the dresser is not equipped with a dressing wheel. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the structure of a grinding pad dresser provided in one embodiment of the present invention;

[0028] Figure 2 A schematic structural diagram of a chemical mechanical polishing device provided in one embodiment of the present invention.

[0029] Description of reference numerals:

[0030] 100-base; 200-swing arm; 300-dressing head; 400-dressing wheel; 500-through-beam sensor; 510-transmitter; 520-receiver;

[0031] 10-grinding table; 11-grinding pad; 20-grinding head; 21-silicon wafer; 30-grinding liquid supplier; 40-grinding pad dresser. DETAILED DESCRIPTION

[0032] The following is a further detailed description of the polishing pad dresser and chemical mechanical polishing equipment proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are in a very simplified form and all use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In order to make the purposes, features and advantages of the present invention more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structures, proportions, sizes, etc. illustrated in the accompanying drawings of this specification are only used to match the contents disclosed in the specification, so that people familiar with this technology can understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope of the technical content disclosed by the present invention.

[0033] As described in the background technology, during the maintenance of existing chemical mechanical polishing equipment, engineers may forget to install the new dressing wheel under the dressing head after disassembling the dressing wheel that needs to be replaced, and the machine will also perform grinding without the dressing wheel installed. If the polishing pad is glazed, the surface of the silicon wafer will be scratched.

[0034] In order to avoid the above situation, an embodiment of the present invention provides a polishing pad dresser, see Figure 1The polishing pad dresser includes a base 100, a swing arm 200, a dressing head 300, a dressing wheel 400 and a through-beam sensor 500, one end of the swing arm 200 is connected to the base 100, the other end of the swing arm 200 can swing back and forth in the horizontal direction, the dressing head 300 is connected to the other end of the swing arm 200, the dressing head 300 can rotate, the dressing wheel 400 is arranged below the dressing head 300, and the dressing wheel 400 rotates driven by the dressing head 300, the through-beam sensor 500 includes a transmitter 510 and a receiver 520, the transmitter 510 and the receiver 520 are arranged at the same horizontal height as the dressing wheel 400, and the dressing wheel 400 is on the connecting line between the transmitter 510 and the receiver 520.

[0035] In the above embodiment, when the dressing wheel 400 is installed, the laser emitted by the transmitter 510 is blocked by the dressing wheel 400, and the receiver 520 cannot receive the laser emitted by the transmitter 510. When the dressing wheel 400 is not installed, the laser emitted by the transmitter 510 directly irradiates the receiver 520, triggering an alarm, and being able to monitor whether the dressing wheel 400 is installed under the dressing head 300, thereby avoiding the situation in the prior art where the table will also perform grinding when the dressing wheel 400 is not installed on the dresser. In addition, the grinding pad dresser provided in this embodiment can also monitor whether the dressing wheel 400 falls off. If the dressing wheel 400 falls off, the receiver 520 will receive the laser emitted by the transmitter 510, and thus being able to trigger an alarm.

[0036] In some embodiments, at least two threaded holes are provided on the trimming head 300, at least two through holes are provided at corresponding positions of the trimming wheel 400, and at least two screws pass through at least two through holes to fix the trimming wheel 400 below the trimming head 300. For example, three threaded holes may be provided on the trimming head 300, and three through holes are also provided at corresponding positions on the trimming wheel 400, and three screws pass through the three through holes to fix the trimming wheel 400 on the trimming head 300. In other embodiments, other numbers of threaded holes may be provided on the trimming head 300, and other numbers of screws may be used to fasten the trimming wheel 400 to the trimming head 300, which is not specifically limited here. In addition, in other embodiments, the trimming wheel 400 may be connected to the trimming head 300 by magnetic attraction.

[0037] In some embodiments, the transmitter 510 is disposed on the side of the base 100 facing the dressing wheel 400, and the receiver 520 is disposed on the side of the dressing wheel 400 facing away from the transmitter 510, and the position is fixed. For example, the receiver 520 can be fixedly disposed on the inner wall (not shown) of the outer shell of the chemical mechanical polishing equipment.

[0038] In the above embodiment, the transmitter 510 can be set on the side of the base 100 facing the dressing wheel 400 by fastening methods such as screws or welding, and the transmitter 510 and the dressing wheel 400 are at the same horizontal height, so that the laser emitted by the transmitter 510 can be blocked by the dressing wheel 400; the receiver 520 is set on the side of the dressing wheel 400 facing away from the transmitter 510, so that when the dressing wheel 400 is not installed, the laser emitted by the transmitter 510 can be received by the receiver 520. Furthermore, it is possible to determine whether the trimming wheel 400 is installed below the trimming head 300 based on whether the receiver 520 receives the laser emitted by the transmitter 510. If the receiver 520 receives the laser emitted by the transmitter 510, the trimming wheel 400 is not installed below the trimming head 300. If the receiver 520 does not receive the laser emitted by the transmitter 510, the trimming wheel 400 is installed below the trimming head 300.

[0039] In some embodiments, the receiver 520 is disposed on the side of the base 100 facing the dressing wheel 400, and the transmitter 510 is disposed on the side of the dressing wheel 400 facing away from the receiver 520, that is, the installation positions of the transmitter 510 and the receiver 520 can be interchanged, which is not specifically limited in this embodiment.

[0040] It should be noted that the transmitter 510 or the receiver 520 is not limited to be installed on the base 100, and can also be installed on the swing arm 200. It is only necessary to ensure that the installation position of the transmitter 510 or the receiver 520 is at the same horizontal height as the dressing wheel 400. By setting the transmitter 510 or the receiver 520 on the base 100, there is no need to add a new installation structure, which can reduce material costs.

[0041] In some embodiments, the distance between the transmitter 510 and the trimming wheel 400 is no greater than the length of the swing arm 200, which can ensure that when the trimming wheel 400 is installed, the trimming wheel 400 can completely block the laser emitted by the transmitter 510 and no false alarm will be generated.

[0042] In some embodiments, the distance between the receiver 520 and the trimming wheel 400 is no greater than the length of the swing arm 200, which can ensure that when the trimming wheel 400 is not installed, the receiver 520 can receive the emitted laser and generate an alarm in time.

[0043] In some embodiments, the surface of the dressing wheel 400 facing away from the dressing head 300 is provided with diamonds, which can remove abrasive particles and abrasive debris aggregates filled in the grooves of the grinding pad and restore the surface roughness of the grinding pad.

[0044] This embodiment provides a chemical mechanical polishing device. Figure 2 , comprising a grinding table 10, a grinding head 20, a grinding liquid supplier 30 and a grinding pad dresser 40 as described in any of the above embodiments, wherein a grinding pad 11 is arranged on the grinding table 10, and a plurality of annular grooves are arranged on the upper surface of the grinding pad 11; the grinding head 20 is arranged above the grinding pad 11, and the surface opposite to the grinding pad 11 is used for adsorbing the silicon wafer 21; the grinding liquid supplier 30 is arranged above the grinding pad 11, and is used for providing grinding liquid during the grinding process; the grinding pad dresser 40 is used for regularly dressing the upper surface of the grinding pad 11.

[0045] The chemical mechanical polishing equipment provided in this embodiment includes the polishing pad dresser 40 provided in the above embodiment, which can monitor whether the dressing wheel 400 is installed under the dressing head 300, thereby avoiding the situation in the prior art where the stage will also perform grinding when the dresser is not equipped with the dressing wheel 400.

[0046] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0047] In the description of the present invention, it should be understood that the terms "center", "height", "thickness", "up", "down", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0048] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" 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 the present invention can be understood according to specific circumstances.

[0049] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0050] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

Claims

1. A grinding pad dresser, characterized in that: include: Pedestal; A swing arm, one end of which is connected to the base, and the other end of which is capable of swinging back and forth in a horizontal direction; A trimming head, the trimming head is connected to the other end of the swing arm, and the trimming head is rotatable; A dressing wheel, which is arranged below the dressing head and rotates under the drive of the dressing head; The through-beam sensor comprises a transmitter and a receiver, wherein the transmitter and the receiver are arranged at the same level as the trimming wheel, and the trimming wheel is located on a line between the transmitter and the receiver.

2. The polishing pad dresser according to claim 1, wherein: At least two threaded holes are arranged on the trimming head, at least two through holes are arranged at corresponding positions on the trimming wheel, and at least two screws pass through at least two through holes to fix the trimming wheel below the trimming head.

3. The polishing pad dresser according to claim 1, wherein: The transmitter is arranged on a side of the base facing the dressing wheel, and the receiver is arranged on a side of the dressing wheel facing away from the transmitter, and the position of the receiver is fixed.

4. The polishing pad dresser according to claim 1, wherein: The receiver is arranged on a side of the base facing the dressing wheel, and the transmitter is arranged on a side of the dressing wheel facing away from the receiver, and the position of the transmitter is fixed.

5. The polishing pad dresser according to claim 1, wherein: The distance between the transmitter and the dressing wheel is no greater than the length of the swing arm.

6. The polishing pad dresser according to claim 1, wherein: The distance between the receiver and the dressing wheel is no greater than the length of the swing arm.

7. The polishing pad dresser according to claim 1, wherein: The surface of the dressing wheel facing away from the dressing head is provided with diamonds.

8. A chemical mechanical polishing device, characterized in that: include: A grinding table, wherein a grinding pad is arranged on the grinding table, and a plurality of annular grooves are arranged on the upper surface of the grinding pad; A grinding head, wherein the grinding head is disposed above the grinding pad, and a surface opposite to the grinding pad is used for adsorbing the silicon wafer; A grinding liquid supplier, which is disposed above the grinding pad and is used to provide grinding liquid during the grinding process; The polishing pad dresser according to any one of claims 1 to 7, used for regularly dressing the upper surface of the polishing pad.

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