Processing device of polishing pad base material

Abstract

To provide a processing device of a polishing pad base material which may automatically polish a polished surface of a polishing pad base material.SOLUTION: A processing device of a polishing pad base material of the invention polishes a flat surface to be polished (a polished surface) Wf of a polishing pad base material W with a polishing surface 17a of a polishing body 17. The processing device includes: a first mechanism 1; a second mechanism 3; operation mechanisms 19, 21, 23 which perform polishing; characteristics acquisition means 7 which acquires characteristics of the polished surface Wf; thickness measurement means 9 which measures a thickness of the polishing pad base material W; and a control device 11 which controls the operation mechanisms 19, 21, 23 based on the characteristics and the thickness.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a polishing pad rough material processing device. [Background technology]

[0002] As described in Patent Document 1, when manufacturing a polishing pad, a buffing process is performed on the flat polished surface of the polishing pad raw material using a buffing body in order to reduce variations in thickness and remove unwanted bubbles that may be inevitably mixed in during the manufacturing process. The configuration of this processing device has not been clear up until now. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2013-169627 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for automation of a processing device that polishes the surface of a polishing pad rough material with the polishing surface of a polishing body such as a buff body.

[0005] The present invention has been made in consideration of the above-mentioned conventional situation, and the problem to be solved is to provide a polishing pad rough material processing device that can automatically polish the polishing surface of the polishing pad rough material. [Means for solving the problem]

[0006] The polishing pad rough material processing device of the present invention is a processing device that polishes a flat polished surface of a polishing pad rough material with a polishing body, a first mechanism for holding the polishing pad rough material and positioning the polished surface in a processing area; a second mechanism for holding the polishing body and positioning the polishing surface in the processing area; an operating mechanism that operates at least one of the first mechanism and the second mechanism to bring the surface to be polished and the polishing surface into contact with each other in the processing area and to perform a polishing process by moving the surface to be polished and the polishing surface relative to each other; a property acquisition means for acquiring the property of the polished surface; a thickness measuring means for measuring the thickness of the polishing pad rough material; The present invention is characterized by comprising a control device that controls the operating mechanism based on the property and the thickness.

[0007] In the processing apparatus of the present invention, a property acquisition means acquires the property of the flat polished surface of the polishing pad rough material, and a thickness measurement means measures the thickness of the polishing pad rough material. Then, a control device controls an operating mechanism based on the property and thickness. The operating mechanism operates at least one of a first mechanism and a second mechanism. The first mechanism holds the polishing pad rough material and positions the polished surface in the processing area. Furthermore, the second mechanism holds a polishing body and positions the polishing surface in the processing area. Therefore, a polishing process is performed in which the polished surface and the polishing surface are brought into contact in the processing area and moved relative to each other.

[0008] Therefore, this processing device can automatically polish the surface to be polished of the polishing pad rough material.

[0009] The polishing pad rough material is a solidified material that constitutes a polishing pad. After the polishing surface of the polishing pad rough material is polished by the polishing surface of the polishing body, in the next step, it is cut into a predetermined shape such as a disk to form a polishing pad. In the polishing pad, the polishing surface of the polishing pad rough material becomes the polishing surface for polishing the object to be polished.

[0010] The polishing body may be a buffing body for performing buffing to adjust the thickness of the polishing pad rough material or to flatten the polished surface, a dressing abrasive body for performing dressing to adjust the condition of the polished surface of the polishing pad rough material, etc. When performing buffing, the polished surface and the polishing surface can be brought into contact based on the position of the polishing surface, and when performing dressing, the polished surface and the polishing surface can be brought into contact under a predetermined surface pressure.

[0011] The property acquisition means can be any device capable of acquiring the property of the polished surface, i.e., the properties and state of the polished surface. The thickness measurement means can be any device capable of measuring the thickness of the polishing pad rough material.

[0012] If the properties do not satisfy the clearing conditions, the control device preferably causes the operating mechanism to execute the polishing process as long as the thickness is above the lower limit. Furthermore, if the properties of the control device satisfy the clearing conditions and the thickness is above the lower limit, the control device preferably causes the operating mechanism to terminate the polishing process and transport the polishing pad rough material to the next process. In this case, after polishing, the polishing pad whose properties satisfy the clearing conditions and whose thickness exceeds the lower limit is transported to the next process. This removes unnecessary air bubbles and the like that may be inevitably mixed in during the manufacturing process, resulting in a high-quality polishing pad for the next process. Various conditions can be adopted as the clearing conditions, as long as they can be determined from the properties acquired by the property acquisition means.

[0013] When the thickness falls below the lower limit, the control device preferably causes the operating mechanism to terminate the polishing process and transport the polishing pad rough to the disposal process. In this case, after polishing, the polishing pad whose thickness falls below the lower limit is transported to the disposal process regardless of whether the properties satisfy the clear conditions. In this way, only high-quality polishing pad rough is transported to the next process.

[0014] The control device preferably causes the operating mechanism to perform the polishing process until the thickness is below the upper limit, regardless of whether the properties meet the clear conditions. During the manufacturing process of the polishing pad rough material, air bubbles may inevitably be mixed into the polishing pad rough material, but these air bubbles are present on or near the surface of the polishing pad rough material. Therefore, if the polishing pad rough material is excessively thick during processing, there is a high possibility that recesses caused by air bubbles will still remain, and the polishing pad rough material needs to be made a little thinner. Furthermore, it is possible to adjust the thickness variation of the polishing pad rough material after polishing and ensure the standard.

[0015] The property acquisition means may be a photographing device that acquires an image of the polished surface as the property. The control device preferably has an image processing unit that determines from the image the number of recesses exceeding a threshold size that may be present on the polished surface, and a judgment unit that determines whether the clearing condition is met based on the number. In this case, the properties of the polishing pad rough material can be acquired without contact. Furthermore, by setting the clearing condition as, for example, the absence of excessively large bubbles that may be inevitably mixed in during the manufacturing process, and the presence of small bubbles within an acceptable range, it becomes possible to transport a high-quality polishing pad to the next process.

[0016] The thickness measuring means may be an eddy current film thickness gauge, an electromagnetic film thickness gauge, an ultrasonic film thickness gauge, or an ultrasonic film thickness gauge. Because eddy current film thickness gauges are superior to other thickness measuring means in terms of accuracy, measurement range, and versatility, it is preferable to use an eddy current film thickness gauge as the thickness measuring means. Because an eddy current film thickness gauge requires the generation of eddy currents in a stage on which an object whose thickness is to be measured is placed, when an eddy current film thickness gauge is used as the thickness measuring means, a first mechanism having a stage on which a polishing pad rough material is placed is employed. That is, the first mechanism may have a stage on which the polishing pad rough material is placed. The thickness measuring means may be an eddy current film thickness gauge that measures the thickness by generating eddy currents in the stage through the polishing pad rough material.

[0017] The polishing body may be an endless strip with the polishing surface facing outward. The second mechanism may include a first roller rotatable about a first axis parallel to the surface to be polished, and a second roller located in the processing area and rotatable about a second axis parallel to the first axis, spaced apart from the first roller. The polishing body is preferably wound between the first and second rollers. In this case, the polishing surface of the polishing pad rough material can be polished by circulating the polishing body between the first and second rollers. Furthermore, circulating the polishing body between the first and second rollers allows polishing to be performed by the entire polishing body, thereby extending the life of the polishing body.

[0018] It is preferable that the distance between the second roller and the first roller is changeable. In this case, the tension on the polishing body can be adjusted by changing the distance between the first roller and the second roller.

[0019] Examples of polishing pad materials that can be used include polishing pads made of polyurethane foam, polishing pads made of nonwoven fabric, and other materials such as polishing pads also known as LHA (Loosely Held Abrasive) pads, which are made of a binder resin and have a base material with multiple pores formed therein and abrasive particles held in the base material or the pores. LHA pads may have fibers or fillers in the base material or the pores. [Effects of the Invention]

[0020] According to the processing apparatus of the present invention, the surface to be polished of the polishing pad rough material can be automatically polished. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a schematic side view of the processing apparatus of the embodiment. [Figure 2] FIG. 2 is a schematic top view of the processing apparatus of the embodiment. [Figure 3] FIG. 3 is a block diagram of the processing device of the embodiment. [Figure 4]FIG. 4 is a flowchart executed by the control device in the processing device of the embodiment. [Figure 5] FIG. 5 is an explanatory diagram of the operating state of the processing device of the embodiment. [Figure 6] FIG. 6 is an explanatory diagram of the operating state of the processing device of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. As shown in Figures 1 and 2, this processing device includes a chuck table 1, a buffing machine 3, a plurality of rollers 5, four area cameras 7, three film thickness meters 9, and a control device 11 shown in Figure 3.

[0023] 1 and 2, numerous suction ports (not shown) are formed on the horizontal upper surface of the chuck table 1. Each suction port is connected to a pump (not shown), and is capable of sucking a rectangular polishing pad rough material W placed on the upper surface by negative pressure. The chuck table 1 corresponds to the first mechanism and the mounting table.

[0024] The buffing machine 3 has a first roller 13, a second roller 15, and a buffing cloth 17. The first roller 13 is rotatable about a first axis 13a parallel to the upper surface of the chuck table 1. The second roller 15 is rotatable about a second axis 15a parallel to the first axis 13a, and is spaced downward from the first roller 13. The first roller 13 is connected to a polishing drive device 19 shown in FIG. 3.

[0025] 1 and 2, the buffing cloth 17 has countless abrasive grains made of alumina or silicon carbide fixed to a base cloth, and is an endless strip with the polishing surface 17a, where the abrasive grains are exposed, facing outward. The buffing cloth 17 is wound around the first roller 13 and the second roller 15. The buffing machine 3 corresponds to the second mechanism. The buffing cloth 17 is the polishing body.

[0026] The processing apparatus also includes a cylinder device 21 shown in Fig. 3. As shown in Figs. 1 and 2, the cylinder device 21 has a cylinder body 21a and a rod 21b. The cylinder body 21a is fixed to the first axis 13a, and the rod 21b is fixed to the second axis 15a. The cylinder body 21a is fixed to a frame (not shown), and the rod 21b is provided so as to be extendable and contractible downward from the cylinder body 21a.

[0027] 1 and 2 are connected to a horizontal drive device 23 shown in Fig. 3, so that the chuck table 1 can be moved forward or backward. As shown in Figs. 1 and 2, the roller 5 located below the second roller 15 has a larger diameter than the other rollers 5 in order to receive the surface pressure acting during buffing. The polishing drive device 19, the cylinder device 21, and the horizontal drive device 23 correspond to an operating mechanism.

[0028] Each area camera 7 individually photographs the polishing surface Wf of the polishing pad rough material W on the chuck table 1 and acquires an image of its properties. The four area cameras 7 are capable of photographing the entire polishing surface Wf. The processing device has multiple light sources that illuminate the polishing surface Wf of the polishing pad rough material W. Each area camera 7 corresponds to an imaging device and property acquisition means.

[0029] Each film thickness meter 9 is an eddy current film thickness meter that, while in contact with the polishing pad rough material W, generates an eddy current in the chuck table 1 via the polishing pad rough material W to measure the thickness of the polishing pad rough material W. Each film thickness meter 9 corresponds to a thickness measuring means. Each film thickness meter 9 is provided at equal intervals in the width direction of the polishing pad rough material W parallel to the first and second axis centers 13a, 13b.

[0030] Dust collection ducts 25a and 25b are provided in front of and behind the first roller 13 near the buff cloth 17. The dust collection ducts 25a and 25b are connected to a dust collector (not shown).

[0031] The control device 11 shown in Fig. 3 is connected to a polishing drive device 19, a cylinder device 21, a horizontal drive device 23, each area camera 7, and each film thickness meter 9. The control device 11 also has an image processing unit 11a configured as an application. The control device 11 also has a judgment unit 11b. The judgment unit 11b is configured by an electronic circuit unit including a microcomputer, memory, interface circuit, etc. Programs for controlling these components are stored in the memory.

[0032] The polishing pad rough material W, which is called an LHA pad and is not yet made into a polishing pad, is formed and then processed by this processing device. During this process, the control device 13 performs the processing shown in the flowchart in Figure 4. First, in step S1, the polishing drive device 19, cylinder device 21, horizontal drive device 23, each area camera 7, and each film thickness gauge 9 are initialized. In the cylinder device 21, the rod 21b is retracted into the cylinder body 21a, shortening the distance between the first roller 13 and the second roller 15, and separating the polishing surface 17a from the polished surface Wf. The polishing pad rough material W is also sucked into the chuck table 1. The dust collector is also activated.

[0033] Then, in step S2, the horizontal drive device 23 is operated, and the polishing pad rough material W is transported together with the chuck table 1 so that the polishing pad rough material W is positioned in the processing area below the second roller 15. Thereafter, the polishing drive device 19 is operated, and the first roller 13 is driven.

[0034] Next, the rod 21b is extended from the cylinder body 21a by the cylinder device 21. This changes the distance between the first roller 13 and the second roller 15, thereby adjusting the tension of the buff cloth 17. Then, while checking the position of the polishing surface 17a of the buff cloth 17 using the gap between the chuck table 1 and the second roller 15, the buff cloth 17 is circulated between the first roller 13 and the second roller 15. In this way, the polished surface Wf of the polishing pad rough material W is polished and buffed.

[0035] In this way, by circulating the buff cloth 17 between the first roller 13 and the second roller 15, polishing can be performed using the entire buff cloth 17, thereby extending the life of the buff cloth 17. During this time, the horizontal drive device 23 moves the polishing pad rough material W back and forth together with the chuck table 1 for a certain period of time so that the entire surface to be polished Wf is buffed by the polishing surface 17a.

[0036] The polishing powder generated during polishing is collected in a dust collector through dust collection ducts 25a and 25b, so that clogging of the chuck table 1 does not occur.

[0037] Thereafter, in step S3, the horizontal drive device 23 stops, and each film thickness meter 9 measures the thickness of the polishing pad rough material W. Next, in step S4, the judgment unit 11b of the control device 11 calculates the average value of the thicknesses measured by each film thickness meter 9, and judges whether the average value is equal to or less than the upper limit value.

[0038] If the answer is No in step S4, the process returns to step S2. This is because, as shown in Fig. 5, air bubbles can inevitably be mixed into the polishing pad rough material W during the manufacturing process, and the air bubbles are present on or near the surface of the polishing pad rough material W. For this reason, if the polishing pad rough material W during processing is excessively thick, there is a high possibility that recesses R caused by air bubbles still remain, and the polishing pad rough material W needs to be made a little thinner. Furthermore, since the polishing pad rough material W during processing is excessively thick, the polishing pad rough material W needs to be made a little thinner in accordance with product specifications.

[0039] If the answer is Yes in step S4, it is determined that the polishing pad rough material W being processed has an appropriate thickness, as shown in Figure 6, and the process proceeds to step S5. In step S5, each area camera 7 captures an image. The image processing unit 11a processes each image. At this time, since the polishing pad rough material W has an appropriate thickness, the recesses R are clearly identified, and the judgment unit 11b accurately determines the total number of recesses R whose size exceeds the threshold and can exist on the polished surface Wf.

[0040] In the next step S6, it is determined whether the total number of recesses R satisfies the clear condition. The clear condition is to allow small air bubbles that are not excessively present and that may be unavoidably mixed in during the manufacturing process, but to not allow excessively large air bubbles.

[0041] If the answer is Yes in step S6, the horizontal drive device 23 operates again, and the process proceeds to step S7 to transport the polishing pad rough material W to the next process. As a result, only high-quality polishing pad rough material is transported to the next process. In the next process, the polishing pad rough material W is cut into a predetermined shape, such as a disk shape. This allows it to be shipped as a polishing pad. The polished surface wf of the polishing pad rough material W becomes the polishing surface for polishing the object to be polished in the polishing pad.

[0042] If the answer is No in step S6, the polishing pad rough material W still has recesses R exceeding the threshold value remaining, so the process proceeds to step S8, where the same buffing process as in step S2 is performed again.

[0043] Thereafter, in step S9, similar to step S3, the horizontal driving device 23 stops, and each film thickness meter 9 measures the thickness of the polishing pad rough material W. Next, in step S10, the judgment unit 11b of the control device 11 judges whether the average value of the thicknesses measured by each film thickness meter 9 is equal to or less than the lower limit value.

[0044] If the answer is No in step S10, the polishing pad rough material W is still thick enough to be buffed, so the process returns to step S5. If the answer is Yes in step S10, the polishing pad rough material W is no longer thick enough to be buffed, so the process proceeds to step S11, where the polishing pad rough material W is transported to a disposal process. After step S7 or step S11, the process moves on to processing the next polishing pad rough material W.

[0045] As described above, in this processing apparatus, the area camera 7 acquires an image of the properties of the flat polished surface Wf of the polishing pad rough material W, and the film thickness meter 9 measures the thickness of the polishing pad rough material W. Then, the control device 11 controls the polishing drive device 19, the cylinder device 21, and the horizontal drive device 23 based on the image and the thickness. Therefore, in the processing area, the polished surface Wf and the polishing surface 17a are brought into contact with each other under a predetermined surface pressure, and the polished surface Wf and the polishing surface 17a are moved relative to each other during the polishing process.

[0046] Therefore, according to this processing device, the polishing surface Wf of the polishing pad rough material W can be polished automatically.

[0047] Although the present invention has been described above with reference to the examples, it goes without saying that the present invention is not limited to the above examples and can be modified and applied as appropriate within the scope of the invention.

[0048] For example, in the embodiment, the buff cloth 17 is used as the polishing body, but the polishing body may be a dressing polishing body that is used to perform a dressing process to adjust the condition of the polished surface of the polishing pad rough material. In this case, the polishing pad itself will have been dressed when shipped. [Industrial Applicability]

[0049] The present invention can be used in a polishing pad manufacturing apparatus. [Explanation of symbols]

[0050] W...Polishing pad coarse material Wf…Surface to be polished 17...Abrasive body (buff cloth) 17a...Polished surface 1...First mechanism, mounting table (chuck table) 3...Second mechanism (buffing machine) 19, 21, 23... Operating mechanism (19... Polishing drive device, 21... Cylinder device, 23... Horizontal drive device) 7...Property acquisition means (area camera, photographing device) 9...Thickness measurement means (film thickness gauge, eddy current film thickness gauge) 11...Control device R...Concave 11a...Image processing unit 11b...judgment section 13a...1st axis center 13...First roller 15a…Second axis center 15...Second roller

Claims

1. A processing device that polishes a flat surface to be polished of a polishing pad rough material with a polishing surface of a polishing body, a first mechanism for holding the polishing pad rough material and positioning the polished surface in a processing area; a second mechanism for holding the polishing body and positioning the polishing surface in the processing area; an operating mechanism that operates at least one of the first mechanism and the second mechanism to bring the surface to be polished and the polishing surface into contact with each other in the processing area and to perform a polishing process by moving the surface to be polished and the polishing surface relative to each other; a property acquisition means for acquiring the property of the polished surface; a thickness measuring means for measuring the thickness of the polishing pad rough material; A processing device for polishing pad rough material, comprising a control device for controlling the operating mechanism based on the properties and the thickness.

2. If the property does not satisfy the clear condition, the control device causes the operating mechanism to perform the polishing process as long as the thickness is above a lower limit value; A processing device for polishing pad rough material as described in claim 1, which, if the properties meet the clear conditions and the thickness exceeds the lower limit value, causes the operating mechanism to terminate the polishing process and transport the polishing pad rough material to the next process.

3. 3. The polishing pad rough material processing device of claim 2, wherein the control device causes the operating mechanism to terminate the polishing process and transport the polishing pad rough material to a disposal process when the thickness falls below the lower limit value.

4. The polishing pad rough material processing device according to claim 2 or 3, wherein the control device causes the operating mechanism to perform the polishing process until the thickness becomes equal to or less than an upper limit value, regardless of whether the properties satisfy the clear condition.

5. the property acquisition means is an imaging device that acquires an image of the polished surface as the property, the control device includes an image processing unit that determines, from the image, the number of recesses that may exist on the polished surface and have a size exceeding a threshold value; 2. The polishing pad rough material processing device according to claim 1, further comprising a determining unit for determining whether the clear condition is met based on the number of pieces.

6. the first mechanism has a mounting table on which the polishing pad rough material is mounted, 2. The apparatus for processing a rough polishing pad according to claim 1, wherein said thickness measuring means is an eddy current film thickness meter which generates an eddy current in said stage through said rough polishing pad to measure said thickness.

7. the polishing body is in the form of an endless strip with the polishing surface facing outward; the second mechanism has a first roller rotatable about a first axis parallel to the surface to be polished, and a second roller located in the processing area, rotatable about a second axis parallel to the first axis, and spaced apart from the first roller; 2. The apparatus for processing a rough polishing pad according to claim 1, wherein the polishing body is wound between the first roller and the second roller.

8. 8. The apparatus for processing a rough polishing pad according to claim 7, wherein the distance between the second roller and the first roller is variable.

9. 2. The polishing pad rough material processing device according to claim 1, wherein the polishing pad rough material comprises a base material made of a binder resin and having a plurality of pores formed therein, and abrasive particles held in the base material or the pores.

Images