JP5464386B2 - Dressing device and manufacturing device using processing tool dressed by this dressing device - Google Patents

Description

  The present invention relates to a dressing apparatus for dressing a processing surface of a processing tool for performing polishing, grinding, lapping processing, and the like, and a manufacturing apparatus using a processing tool dressed by such a dressing apparatus.

  Machining tools that perform polishing, grinding, lapping, etc. will be deteriorated as clogging of the machining surface progresses according to the machining time, so maintenance is performed so that good machining is always performed by regular dressing . As such a processing tool, for example, there is a polishing pad used in a chemical mechanical polishing apparatus (CMP apparatus) for polishing a circuit component film formed on the wafer surface in a semiconductor wafer manufacturing process. Also, dressing with a dressing tool is performed at predetermined intervals. An example of such a dressing device is disclosed in Japanese Patent Application Laid-Open No. 2003-80456 (see, for example, Patent Document 1).

JP 2003-80456 A

  However, the influence of the dressing time on the polishing pad, which is a processing tool, is not limited. Therefore, in order to grasp the influence on the polishing process by performing dressing, it is necessary to accurately grasp the time for performing dressing.

  This invention is made | formed in view of such a problem, and it aims at providing the dressing apparatus which can grasp | ascertain correctly the time when dressing is performed. Moreover, it aims at providing the manufacturing apparatus using the processing tool dressed by this dressing apparatus.

In order to achieve such an object, a dressing apparatus according to the present invention includes a dressing tool and a drive source that rotationally drives the dressing tool, and contacts the dressing surface of the dressing tool by rotating the dressing tool within the dressing surface. In a dressing apparatus for dressing a processing tool, the dressing surface is in contact with the processing surface based on the torque measuring means for measuring the rotational driving torque of the driving source and the rotational driving torque of the driving source measured by the torque measuring means. Dressing time measuring means for measuring time, and the dressing time measuring means is in a state where the dressing surface is in contact with the machining surface when the rotation direction of the dressing tool is reverse to the rotation direction of the machining tool The dressing surface is processed based on the rotational drive torque value measured in advance at Configured to measure the contact I have the time to.

In the above-described invention, the dressing time measuring means performs processing when the dressing surface processes the time when the time change characteristic of the rotational driving torque measured by the torque measuring means shows a predetermined fluctuation characteristic when dressing the processed surface. It is preferable to measure as the time of contact with the surface. In the above-mentioned invention, it is preferable that the dressing time measuring means measures, as the predetermined fluctuation characteristic, the time when the rotational driving torque has changed near 0 as the time when the dressing surface is in contact with the processing surface.

  Furthermore, the manufacturing apparatus according to the present invention is configured to process a workpiece using a processing tool dressed by the dressing apparatus according to the present invention.

  According to the present invention, it is possible to accurately grasp the time during which dressing is performed, thereby making it possible to more appropriately set the processing conditions after dressing.

It is a front view which shows schematic structure of the dressing apparatus which concerns on this invention. It is a top view which shows schematic structure of the said dressing apparatus. It is a graph which shows the relationship between the run-out amount of a dressing tool, and time. It is a graph which shows the relationship between the drive torque of a servomotor, and time.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. A polishing pad dressing apparatus DA according to the present invention is shown in FIG. This dressing device DA is a device for dressing a polishing surface 16 (processing surface) of a polishing pad 15 (processing tool) used in a CMP apparatus for polishing a semiconductor wafer or the like, and holds the polishing pad 15 by vacuum suction or the like. Rotating pad holding mechanism 10 (processing tool holding means), a dressing tool 1 for dressing the polishing surface 16 of the polishing pad 15 held and rotated by the pad holding mechanism 10, and the dressing tool 1 being rotatable. It comprises a dressing tool holding mechanism 5 (dressing tool holding means) for holding.

  The pad holding mechanism 10 includes a pad holding head 11 that holds the polishing pad 15 by vacuum suction, a rotary shaft 12 that is connected to the pad holding head 11, and the pad holding head 11 that rotates in a substantially horizontal plane via the rotary shaft 12. And a rotational drive device that does not. The polishing pad 15 is made of a plate-like member having a doughnut-shaped polishing surface 16 and is held by the pad holding head 11 so that an axis passing through the center point and perpendicular to the polishing surface 16 is the center of rotation. .

  The dressing tool 1 is formed in a disk shape having a circular dressing surface 2 having a smaller diameter than the polishing surface 16 of the polishing pad 15. The dressing tool holding mechanism 5 includes a base member 6, a main body case member 7 attached to the upper side of the base member 6, a rotary shaft member 8 attached to the main body case member 7 so as to be rotatable and vertically movable, The dressing tool 1 is configured so as to have a tool holding member 9 that is fixed to the upper end of the rotary shaft member 8 and holds the dressing tool 1, and the dressing tool 1 is substantially horizontal so that the dressing surface 2 faces the polishing surface 16 of the polishing pad 15. It is held so as to be rotatable and vertically movable within.

  Inside the main body case member 7, a servo motor 21 that rotationally drives the rotary shaft member 8 and the tool holding member 9, a cylinder mechanism (not shown) that moves the rotary shaft member 8 and the tool holding member 9 up and down, and the like are disposed. . Then, by the operation of the servo motor 21 and the cylinder mechanism, the dressing tool 1 held by the tool holding member 9 moves upward while rotating, and the dressing surface 2 of the dressing tool 1 is rotated (in a rotating state). It is pressed against the polishing surface 16 of the pad 15. The rotational force and pressing force of the dressing tool 1 at this time are set and controlled to appropriate values by a controller 30 (not shown in detail), and dressing of the polishing surface 16 is performed.

  As shown in FIGS. 1 and 2, two displacement sensors 22 and 23 are attached to the side of the dressing tool 1 at the upper part of the main body case member 7, and are in a plane parallel to the dressing surface 2 (in a horizontal plane). The amount of deflection (in the horizontal direction) of the dressing tool 1 from a predetermined reference position is measured. Note that the deflection amount of the dressing tool 1 measured by the displacement sensors 22 and 23 is output to the controller 30. Further, as shown in FIG. 2, two water supply devices 24 and 25 are attached to the main body case member 7, and cleaning is performed toward the dressing surface 2 of the dressing tool 1 and the polishing surface 16 of the polishing pad 15, respectively. It is designed to supply water for use.

  In the dressing apparatus DA having such a configuration, as described above, the dressing tool 1 held by the tool holding member 9 moves upward while rotating by the operation of the servo motor 21 and the cylinder mechanism, and the dressing tool 1 is dressed. The surface 2 is pressed against the polishing surface 16 of the rotating polishing pad 15 (in a rotating state). Then, the controller 30 controls the rotational force and the pressing force of the dressing tool 1 to appropriate values, so that the polishing surface 16 is dressed.

  Further, in the present embodiment, the controller 30 is the time that the dressing surface 2 is actually in contact with the polishing surface 16 based on the deflection amount of the dressing tool measured by the displacement sensors 22 and 23 (that is, the dressing is performed). Measured time). Thus, by accurately grasping the time during which dressing is performed on the polishing pad 15 (polishing surface 16), it is possible to set the polishing conditions (processing conditions) in the CMP apparatus after dressing more appropriately. Become.

  FIG. 3 shows an example of the relationship between the displacement (runout amount) of the dressing tool and time. From this figure, it can be seen that while the dressing surface 2 is pressed against the polishing surface 16 and dressing is performed, the displacement (runout amount) of the dressing tool changes between 0 and -0.2 mm. At this time, the controller 30 measures the time when the displacement (runout amount) of the dressing tool becomes a value between 0 and −0.2 mm, for example, and the dressing surface 2 makes the polishing surface 16 the measured time. It is measured as the time of contact (that is, the time when dressing is performed). In FIG. 3, the time during which the dressing surface 2 is in contact with the polishing surface 16 is approximately 7 seconds (from approximately 31 minutes 17 seconds to 31 minutes 24 seconds). In addition, you may make it measure the time when the waveform of a graph shows a predetermined shape (waveform near the center part in FIG. 3) as the time when the dressing surface 2 is in contact with the polishing surface 16.

  As a result, according to the dressing apparatus DA according to the present embodiment, the controller 30 makes the dressing surface 2 abut on the polishing surface 16 (processing surface) based on the amount of deflection of the dressing tool 1 measured by the displacement sensors 22 and 23. Since the measured time is measured, the time during which dressing is performed can be accurately grasped, and it becomes possible to set polishing conditions (processing conditions) after dressing more appropriately. In addition, since the time for performing dressing can be accurately grasped, it is not necessary to perform extra dressing, and the life of the polishing pad 15 (processing tool) can be extended.

  In addition, the CMP apparatus (manufacturing apparatus) in the present embodiment is configured to perform the polishing process of the workpiece using the polishing pad 15 dressed by the dressing apparatus DA of the present embodiment. The workpiece can be polished under the set polishing conditions (processing conditions), and the processing accuracy of the polishing can be improved.

  In the above-described embodiment, the dressing device in which the dressing tool 1 is held by the dressing tool holding mechanism 5 below the polishing pad 15 has been described. However, the present invention is not limited to this, and the present invention is not limited to the above. In the dressing apparatus, the dressing tool can be used in a dressing apparatus configured to hold the dressing tool.

  In the above-described embodiment, a CMP apparatus for polishing a semiconductor wafer or the like has been described as an example of the manufacturing apparatus according to the present invention. However, the present invention is not limited to this, and for example, a grinding apparatus or a lapping apparatus may be used. The present invention is applied to any dressing apparatus for dressing the processing surface of a processing tool that performs polishing, grinding, lapping, and the like, and a manufacturing apparatus that uses a processing tool dressed by such a dressing apparatus. be able to.

  Furthermore, in the above-described embodiment, the controller 30 is configured to measure the time during which the dressing surface 2 is in contact with the polishing surface 16 (processed surface). However, the present invention is not limited to this. The dressing time measuring means may be provided separately from the controller.

  In the above-described embodiment, the controller 30 measures the time during which the dressing surface 2 is in contact with the polishing surface 16 (processed surface) based on the deflection amount of the dressing tool 1 measured by the displacement sensors 22 and 23. However, the present invention is not limited to this. For example, as shown by a two-dot chain line in FIG. 1, the dressing surface 2 contacts the polished surface 16 (processed surface) based on the rotational drive torque of the servo motor 21 measured by the torque measuring device 35 (torque measuring means). The contact time may be measured. Even in this case, it is possible to accurately grasp the time during which dressing is performed, and thereby it is possible to set the polishing conditions (processing conditions) after dressing more appropriately.

  Actually, the torque measuring device 35 detects the drive current of the servo motor 21, converts the rotational drive torque of the servo motor 21 estimated from the detected drive current into a voltage, and outputs the voltage to the controller 30. FIG. 4 shows an example of the relationship between the drive torque (voltage) of the servo motor 21 and time. From this figure, when the servo motor 21 is operated and the dressing tool 1 is rotationally driven, while the dressing surface 2 is pressed against the polishing surface 16 and dressing is performed, the drive torque (voltage) of the servo motor 21 is near zero. It can be seen that This is because the rotational drive torque of the rotational drive device that rotates the polishing pad 15 is considerably larger than the rotational drive torque of the servo motor 21, and the rotational direction of the polishing pad 15 and the rotational direction of the dressing tool 1 are the same. This is because there is almost no need to apply a rotational driving torque to the dressing tool 1 at the time of dressing in which 2 is pressed against the polishing surface 16, so that a drive current is not so much output to the servomotor 21.

  At this time, for example, the controller 30 measures the time when the drive torque (voltage) of the servo motor 21 is close to 0, and the measured time is the time during which the dressing surface 2 is in contact with the polishing surface 16 (that is, Measure as dressing time). In FIG. 4, the time during which the dressing surface 2 is in contact with the polishing surface 16 is about 6 seconds (from about 27 minutes 35 seconds to 27 minutes 41 seconds). The time when the waveform of the graph shows a predetermined shape (the waveform near the center in FIG. 4) may be measured as the time when the dressing surface 2 is in contact with the polishing surface 16.

  When the rotation direction of the dressing tool 1 is reversed with respect to the rotation direction of the polishing pad 15, the drive torque (voltage) of the servo motor 21 in a state where the dressing surface 2 is in contact with the polishing surface 16 is Since it is not near 0, the value of the driving torque (voltage) at the time of contact may be measured in advance, and the time of contact using the value of the driving torque (voltage) may be measured.

  As described above, the controller 30 may measure the time that the dressing surface 2 is in contact with the polishing surface 16 (processing surface) based on the driving torque of the servo motor 21 measured by the torque measuring device 35. The time during which dressing is performed can be accurately grasped, and it becomes possible to set polishing conditions (processing conditions) after dressing more appropriately. Further, it is not necessary to perform extra dressing, and the life of the polishing pad 15 (processing tool) can be extended.

DESCRIPTION OF SYMBOLS 1 Dressing tool 2 Dressing surface 5 Dressing tool holding mechanism (dressing tool holding means)
10 Pad holding mechanism (working tool holding means)
15 Polishing pad (processing tool) 16 Polishing surface (processing surface)
21 Servo motor (drive source)
22 Displacement sensor (runout measurement means) 23 Displacement sensor (runout measurement means)
30 controller (dressing time measuring means)
35 Torque measuring device (torque measuring means)

Claims (4)

In a dressing device comprising a dressing tool and a drive source for rotationally driving the dressing tool, and performing dressing of a processing tool that contacts the dressing surface of the dressing tool by rotating the dressing tool in a dressing surface,
Torque measuring means for measuring the rotational driving torque of the driving source;
Dressing time measuring means for measuring the time during which the dressing surface is in contact with the processing surface based on the rotational driving torque of the drive source measured by the torque measuring means ;
The dressing time measuring means has a rotational driving torque measured in advance in a state where the dressing surface is in contact with the processing surface when the rotation direction of the dressing tool is reverse to the rotation direction of the processing tool. A dressing apparatus for measuring a time during which the dressing surface is in contact with the processed surface based on a value .   The dressing time measuring means is a time when the time change characteristic of the rotational driving torque measured by the torque measuring means shows a predetermined fluctuation characteristic when dressing the processed surface, and the dressing surface is the processed surface. The dressing device according to claim 1, wherein the dressing device is measured as a time of contact. The dressing time measuring means measures, as the predetermined variation characteristic, a time during which the rotational driving torque has changed in the vicinity of 0 as a time during which the dressing surface is in contact with the processing surface. 2. The dressing device according to 2 .   A manufacturing apparatus configured to process a workpiece using the processing tool dressed by the dressing apparatus according to any one of claims 1 to 3.

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