TW202216365A - Polishing apparatus and polishing method - Google Patents

Abstract

A polishing apparatus for polishing a workpiece includes a chuck table having a holding surface for holding the workpiece placed on the holding surface under suction thereon, a polishing unit for polishing the workpiece held on the chuck table with a polishing pad while supplying a slurry to the workpiece, and a high-pressure steam ejecting unit having a nozzle for ejecting high-pressure steam to the holding surface of the chuck table. The high-pressure steam ejecting unit ejects high-pressure steam to swarf produced from polishing the workpiece and deposited on an outer circumferential portion of the holding surface for thereby removing the swarf from the holding surface.

Description

Grinding device and grinding method

The present invention relates to a polishing apparatus for polishing a workpiece such as a semiconductor wafer, and a polishing method for polishing the workpiece with the polishing apparatus.

In the process of manufacturing device chips used in electronic devices such as mobile phones and computers, IC (Integrated Circuit) and LSI (Large Scale Integration) are first formed on the front surface of a semiconductor wafer. multiple devices, etc. Next, the wafer is ground from the back side to be thinned to a predetermined thickness, and the wafer is divided for each device to form individual device wafers.

When the back side of the wafer is ground, minute concavities and convexities are formed on the surface to be ground as grinding marks. Therefore, minute concavo-convex shapes remain on the device wafer formed by dividing the wafer. This minute concavo-convex shape is a major factor in reducing the flexural strength of the device wafer. Then, there is known a method of polishing the back surface of the wafer by, for example, a CMP (Chemical Mechanical Polishing) method after grinding (refer to Patent Document 1).

A polishing apparatus for polishing a workpiece such as a wafer includes a work chuck that holds the workpiece, and a polishing unit equipped with a polishing pad that polishes the workpiece that has been held on the work chuck. thing. When a polishing device is used to polish a workpiece, it is possible to remove minute irregularities and process the workpiece into a mirror surface.

In the polishing apparatus, a polishing slurry is supplied as a polishing liquid to the polished surface of the workpiece during polishing of the workpiece. The abrasive slurry is, for example, a chemical liquid in which abrasive grains are dispersed. The polishing slurry acts not only chemically and mechanically to contribute to polishing, but also contributes to the discharge of abrasive dust generated by polishing. The polishing slurry can be supplied to the polishing pad from a supply path provided in the center, and travel between the polishing pad and the workpiece to reach the outer periphery of the workpiece. prior art literature Patent Literature

Patent Document 1: Japanese Patent Application Laid-Open No. 8-99265

The problem to be solved by the invention

The polishing slurry containing grinding dust that has reached the outer periphery of the workpiece falls from the polished surface of the workpiece, accumulates, and is fixed to the outer peripheral portion of the holding surface of the table. Furthermore, when the workpiece is removed from the work table after the grinding of the workpiece is completed, the grinding debris that has been fixed on the upper surface of the table will remain around the place where the workpiece originally existed. area.

When the workpiece to be polished by the polishing pad is carried into the table, the fixed grinding dust may enter between the table and the workpiece, and it may become an obstacle to the transfer. . For example, a method of supplying washing water to the outer peripheral portion of the holding surface of the work chuck is conceivable in order to remove the fixed grinding dust, but it is not easy to remove the fixed grinding dust.

In addition, in order to wash away the polishing slurry containing the polishing dust that has reached the outer peripheral portion of the workpiece before the polishing slurry is fixed, a method is considered as follows: when the workpiece is being polished with the polishing pad, A sufficient amount of cleaning liquid is supplied to the outer peripheral portion of the holding surface of the work chuck. However, if the cleaning liquid is mixed into the polishing slurry that has been supplied between the polishing pad and the workpiece, and the polishing slurry is diluted, there is a possibility that the polishing step cannot be properly performed.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a polishing apparatus and a polishing method which can remove the polishing dust fixed to the outer peripheral portion of the table. means of solving problems

According to one aspect of the present invention, a grinding device can be provided, which is a grinding device for grinding a workpiece, which is characterized by comprising: a work chuck having a holding surface, and a grinding device for grinding the workpiece placed on the holding surface. The workpiece is sucked and held; a grinding unit is used to grind the workpiece with a polishing pad while supplying a polishing slurry to the workpiece held by the work chuck; and a high-pressure steam jet unit is provided with the work chuck The nozzle for spraying high-pressure water vapor on the holding surface can spray high-pressure water vapor from the high-pressure water vapor spraying unit to the grinding dust accumulated on the outer peripheral portion of the holding surface, so as to remove the grinding dust from the holding surface.

According to another aspect of the present invention, there can be provided a grinding method using a grinding device, wherein the grinding device includes: a work chuck for sucking and holding the workpiece placed on the holding surface; And a grinding unit, while supplying a polishing slurry to the workpiece held by the working chuck, grinding the workpiece with a polishing pad, the aforementioned grinding method is characterized by having the following steps: Holding step, the workpiece is placed on the holding surface and held by the work chuck; Grinding step, while supplying abrasive slurry to the workpiece held by the work chuck, grinding the workpiece with the polishing pad; a carrying-out step, carrying out the workpiece that has been ground in the grinding step from the work chuck; and In the grinding dust removal step, high-pressure water vapor is sprayed on the grinding dust accumulated on the outer peripheral portion of the holding surface of the work chuck to remove the grinding dust. Invention effect

In the polishing apparatus and the polishing method of one aspect of the present invention, the workpiece is polished with a polishing pad while supplying the polishing slurry to the workpiece. When the workpiece is ground, the generated grinding dust accumulates and is fixed on the outer peripheral portion of the holding surface of the table. Here, when high-pressure water vapor is sprayed on the grinding dust fixed on the outer peripheral portion of the holding surface, the fixed grinding dust is heated and water is sent in and softened. Therefore, when the high-pressure steam is continuously sprayed, the fixed abrasive dust can be removed from the holding surface relatively easily. If the grinding dust can be removed from the holding surface, a new workpiece can be placed on the holding surface without hindrance.

Therefore, according to one aspect of the present invention, it is possible to provide a polishing apparatus and a polishing method that can remove the polishing dust fixed to the outer peripheral portion of the work chuck.

Form for carrying out the invention

An embodiment of one aspect of the present invention will be described with reference to the accompanying drawings. The object to be polished by the polishing apparatus and polishing method of the present embodiment will be described. FIG. 3 includes a perspective view schematically showing a workpiece 1 such as a semiconductor wafer.

The workpiece 1 may be, for example, a wafer formed of materials such as silicon, SiC (silicon carbide), or other semiconductors, or a substantially disk-shaped substrate formed of materials such as sapphire, glass, and quartz. The front surface 1a of the workpiece 1 is divided into a plurality of regions by a plurality of planned dividing lines (dicing lines) 5 arranged in a grid shape, and ICs, LSIs, etc. are formed in each of the plurality of regions. device 7. Finally, by dividing the workpiece 1 along the planned dividing line 5, individual device wafers can be formed.

The workpiece 1 is thinned by grinding the back surface 1b. On the back surface 1b of the workpiece 1 that has been ground, minute concavo-convex shapes called grinding marks are formed. If a device wafer is produced by dividing the workpiece 1 along the planned dividing line 5 as it is in this state, minute concavo-convex shapes remain on the device wafer, which is a major factor reducing the flexural strength of the device wafer. Then, the back surface 1b side of the workpiece 1 of which the back surface 1b has been ground is ground, and the fine unevenness of the back surface 1b is removed and planarized. As a result, the minute concavo-convex shape does not remain on the device wafer.

When polishing the back surface 1b side of the workpiece 1, the protective tape 3 is attached in advance in order to protect the front surface 1a side of the workpiece 1. The protective tape 3 protects the front surface 1 a of the workpiece 1 from shocks applied when the back surface 1 b of the workpiece 1 is ground or conveyed, and prevents damage to the device 7 .

The protective tape 3 has a base material and a paste layer (adhesive layer), the base material is in the form of a flexible film, and the paste layer is formed on one surface of the base material. For example, as the base material, polyolefin, polyethylene terephthalate, polyvinyl chloride, or polystyrene or the like can be used. Moreover, as a paste layer (adhesive layer), for example, a silicone rubber, an acrylic material, an epoxy material, etc. can be used.

Next, the grinding|polishing apparatus of this embodiment which grinds the back surface 1b of the to-be-processed object 1 as a to-be-polished surface is demonstrated. FIG. 1 is a perspective view schematically showing the polishing apparatus 2 . The polishing apparatus 2 has a base 4 that supports each of the structures. On the upper surface of the front side part of the base 4, cassette mounts 6a and 6b are provided.

On the cassette mounting table 6a, the cassette 8a which accommodates the to-be-processed object 1 before grinding|polishing, for example, can be mounted. For example, a cassette 8b for accommodating the polished workpiece 1 can be placed on the cassette mounting table 6b. A to-be-processed object conveyance robot 10 which conveys the to-be-processed object 1 adjacent to cassette mounting bases 6a, 6b is attached to the base 4. As shown in FIG.

A positioning table 12 and a workpiece carrying mechanism (loading arm) 14 are further disposed on the upper surface of the front side portion of the base 4 , and the positioning table 12 is adjusted by sandwiching the workpiece 1 with a plurality of positioning pins. At the position of the workpiece 1 , the workpiece loading mechanism 14 described above places the workpiece 1 on the table 20 . In addition, a workpiece unloading mechanism (unloading arm) 16 for unloading the workpiece 1 from the table 20, and a rotary cleaning device 52 for washing and spin drying the ground workpiece 1 are provided.

An opening 4 a is provided on the upper surface of the rear side portion of the base 4 . An X-axis moving table 18 is provided in the opening 4a, and the X-axis moving table 18 mounts the table 20 that attracts and holds the workpiece 1 on the upper surface. The X-axis moving table 18 is movable in the X-axis direction by a not-shown X-axis direction moving mechanism. The X-axis moving table 18 can be positioned to the carry-in area 22 and the processing area 24 by the function of the X-axis direction moving mechanism. The area 24 is an area for grinding the workpiece 1 sucked and held on the work chuck 20 .

On the upper surface of the table 20, a disk-shaped porous member having the same diameter as the workpiece 1 is exposed. The upper surface of the table 20 serves as a holding surface 20 a for holding the workpiece 1 . The table 20 is provided with a suction path (not shown) inside, and the suction path has one end connected to the porous member and the other end connected to a suction source not shown. When the suction source is actuated, a negative pressure acts on the workpiece 1 placed on the holding surface 20 a, and the workpiece 1 can be sucked and held by the work chuck 20 . Also, the work clamp table 20 can be rotated about an axis perpendicular to the holding surface 20a.

Above the processing area 24, a grinding unit 26 for grinding the workpiece 1 is disposed. A support portion 28 is erected on the rear end portion of the base 4 of the grinding device 2 , and the grinding unit 26 can be supported by the support portion 28 . A pair of Z-axis guide rails 30 extending in the Z-axis direction is provided on the front surface of the support portion 28 , and a Z-axis moving plate 32 is slidably mounted on each of the Z-axis guide rails 30 .

A nut portion (not shown) is provided on the back side (rear surface side) of the Z-axis moving plate 32 , and the Z-axis ball screw 34 parallel to the Z-axis guide rail 30 is screwed to the nut portion. A Z-axis pulse motor 36 is connected to one end of the Z-axis ball screw 34 . As long as the Z-axis ball screw 34 is rotated by the Z-axis pulse motor 36 , the Z-axis moving plate 32 moves in the Z-axis direction along the Z-axis guide rail 30 . The grinding unit 26 is fixed to the lower part of the front surface side of the Z-axis moving plate 32 . If the Z-axis moving plate 32 is moved in the Z-axis direction, the grinding unit 26 can be moved in the Z-axis direction.

The grinding unit 26 includes a main shaft 40 and a grinding wheel 44 , the main shaft 40 is rotated by a motor connected to the base end side, and the grinding wheel 44 is fixed by a fixture 46 on the front end side of the main shaft 40 . Block 42. The motor is provided in the main shaft housing 38 , and when the motor is activated, the grinding wheel 44 rotates along with the rotation of the main shaft 40 .

FIG. 2 is a perspective view schematically showing the grinding surface side of the grinding wheel 44 . The grinding wheel 44 includes a grinding pad 44b and a wheel seat 44a. The grinding pad 44b is formed of, for example, a felt material with a larger diameter than the back surface 1b of the workpiece 1, such as urethane, and the wheel seat 44a is used for the grinding pad. 44b fixed.

In the wheel base 44a, a plurality of fixing holes (not shown) into which the fixture 46 is inserted are provided on the surface on the opposite side to the surface on which the polishing pad 44b is fixed. A through hole penetrating through the center in the thickness direction is formed in the wheel base 44a and the polishing pad 44b of the polishing wheel 44, and the end of the through hole on the polishing pad 44b side is the polishing liquid supply port 54.

As shown by the dotted line in FIG. 1 , inside the polishing unit 26 , a polishing liquid supply path 50 that penetrates the polishing unit 26 in the Z-axis direction is formed. The upper end side of the polishing liquid supply path 50 is connected to the polishing liquid supply source 48, and when the workpiece 1 is polished, the polishing liquid supply source 48 passes through the polishing liquid supply path 50 toward the center of the polishing pad 44b. The polishing liquid supply port 54 (refer to FIG. 2 ) of the section supplies a polishing liquid called polishing slurry.

The polishing slurry is a chemical solution in which abrasive grains (free abrasive grains) are dispersed, and the material of the abrasive grains, the particle size of the abrasive grains, the type of dispersion medium, and the like can be appropriately selected according to the material of the workpiece 1 .

As abrasive grains, for example, silica, alumina, zirconia, manganese dioxide, ceria, colloidal silica, fumed silica, boehmite can be used. ), α-bayerite, diamond, etc. As the dispersion medium, for example, potassium acetate, potassium chloride, potassium hydroxide, sodium hydroxide, ammonium carbonate, potassium hydrogencarbonate, sodium hydrogencarbonate, imidazole, pyrazole, pyrazine can be used. ) of the alkaline aqueous solution. However, the member contained in the polishing slurry is not limited to this, and other additives and the like may be added.

When polishing the workpiece 1 held by the table 20 positioned in the machining area 24 , the polishing pad 44 b is arranged above the workpiece 1 . Then, the grinding wheel 44 and the table 20 are rotated around their respective axes along the Z-axis direction, and the grinding wheel 44 is lowered so that the polishing pad 44 b is brought into contact with the workpiece 1 . At this time, in order to supply the polishing slurry between the workpiece 1 and the polishing pad 44 b , the polishing liquid supply source 48 is actuated, and the polishing slurry is sent to the polishing liquid supply path 50 .

FIG. 5 is a perspective view schematically showing a state in which the workpiece 1 is ground. When grinding the workpiece 1, for example, it is preferable to set the rotation number of the table 20 to about 300 rpm, and to set the rotation number of the grinding wheel 44 to about 1000 rpm.

The position of the table 20 is adjusted in advance so that the polishing liquid supply port 54 of the polishing pad 44b is blocked by the workpiece 1 . Therefore, the polishing slurry supplied from the polishing liquid supply port 54 remains on the workpiece 1 . When the polishing pad 44b and the workpiece 1 are brought into contact with each other and are rotated around an axis along the Z-axis direction, the polishing slurry penetrates into the polishing pad 44b and the polished surface (back surface) of the workpiece 1. 1b).

When the workpiece 1 is polished with the polishing pad 44b, polishing dust is generated from the surface to be polished (back surface 1b). The polishing dust is taken in by the polishing slurry and discharged toward the outside of the polishing pad 44b. The polishing slurry 56 containing the abrasive dust reaches the outer peripheral portion of the back surface 1 b of the workpiece 1 shortly after, and falls to the outer peripheral portion 20 b of the holding surface 20 a of the table 20 .

After that, a part of the polishing slurry 56 falls off from the work chuck 20 and is discharged from the drain port 4b formed in the opening 4a of the base 4 of the polishing apparatus 2 . On the other hand, the other part of the polishing slurry that has dropped on the outer peripheral portion 20b of the holding surface 20a of the table 20 is dried on the outer peripheral portion 20b and fixed to the outer peripheral portion 20b together with grinding chips . In the back surface 1b of the workpiece 1, although the temperature of the polishing slurry is maintained relatively high due to the processing heat generated by the polishing, the temperature of the polishing slurry that has dropped to the outer peripheral portion 20b of the holding surface 20a is relatively high. It is lowered sharply, so it is easy to improve the fixation.

FIG. 6 is a perspective view schematically showing a state in which the ground workpiece 1 is carried out from the work table 20 . As shown in FIG. 6 , the fixed grinding dust 9 remains on the outer peripheral portion 20 b of the holding surface 20 a of the table 20 .

In the polishing apparatus 2 : successively unloading the plurality of workpieces 1 accommodated in the cassette 8 a and placing them on the table 20 , polishing with the polishing unit 26 , carrying out from the table 20 , It is cleaned by the rotary cleaning device 52 and accommodated in the cassette 8b. Then, the workpiece 1 to be polished next is placed on the holding surface 20a on which the fixed grinding dust 9 remains on the outer peripheral portion 20b.

When the grinding of the workpiece 1 is repeated for a plurality of pieces, the grinding dust 9 is successively deposited on the outer peripheral portion 20b of the holding surface 20a. In addition, if the amount of the grinding dust 9 fixed to the outer peripheral portion 20b increases, when a new workpiece 1 is placed on the table 20, the grinding dust 9 may enter the workpiece 1 and the holding surface. Doubts between 20a. In this case, since the workpiece 1 cannot be appropriately held by the work chuck 20 , the workpiece 1 cannot be properly ground by the grinding unit 26 .

For example, it is possible to spray water on the grinding dust 9 to clean the holding surface 20a of the table 20 , but simply spraying water has a low cleaning effect and cannot completely remove the grinding dust 9 . In addition, although it is possible to grind the holding surface 20a of the table 20 mechanically, there is a possibility that the grinding dust 9 fixed to the holding surface 20a will be dragged and damaged on the holding surface 20a.

Therefore, in the polishing apparatus 2 of the present embodiment, the table 20 on which the polishing dust 9 is adhered to the outer peripheral portion 20b of the holding surface 20a is washed with high-pressure water vapor. In the polishing apparatus 2, for example, a high-pressure steam spray unit 58 is provided in the vicinity of the carry-in and carry-out area 22 in which carry-in and carry-out of the workpiece 1 is carried out.

FIG. 7(A) is a perspective view schematically showing the work chuck 20 to which the high-pressure water vapor 60 is sprayed by the high-pressure water vapor spray unit 58 . The high-pressure steam spraying unit 58 is, for example, a tubular shape including a shaft portion 58a extending in the Z-axis direction, an arm portion 58b extending in the horizontal direction from the upper end of the shaft portion 58a, and a nozzle 58c provided at the tip of the arm portion 58b. member. The high-pressure water vapor injection unit 58 may rotate the arm part 58b by rotating the shaft part 58a, for example, so that the nozzle 58c may be positioned at a predetermined position.

A high-pressure steam supply source (not shown) is connected to the lower end of the shaft portion 58a. The high-pressure steam supply source includes, for example, a heating unit (not shown) that heats water to a predetermined temperature. The high-pressure water vapor spray unit 58 sprays, for example, water vapor heated to about 105° C. to the outer peripheral portion 20 b of the holding surface 20 a of the table 20 at a pressure of about 0.3 MPa.

When cleaning the outer peripheral portion 20b of the holding surface 20a of the table 20, it is preferable to rotate the table 20 at a rotation speed of, for example, about 30 rpm. In this way, the high-pressure water vapor 60 can be jetted over the entire circumference of the outer peripheral portion 20b of the holding surface 20a.

When the high-pressure water vapor 60 is sprayed on the grinding dust 9 fixed to the outer peripheral portion 20b of the holding surface 20a, the grinding dust 9 is heated and contacts water, so that the grinding dust 9 is softened. Then, if the injection of the high-pressure water vapor 60 is continued, the grinding dust 9 can be peeled off and removed from the outer peripheral portion 20b of the holding surface 20a in a short time.

In addition, it is preferable to spray water from the porous member forming the holding surface 20 a of the work chuck 20 while the high-pressure water vapor 60 is sprayed from the high-pressure water vapor spray unit 58 . In this case, since the grinding dust 9 peeled from the outer peripheral portion 20b can be discharged to the outside of the holding surface 20a of the table 20 without entering the porous member, the peeled grinding dust 9 can be suppressed. Problems such as reattachment to the holding surface 20a.

Here, the nozzle 58c of the high-pressure water vapor injection unit 58 is preferably directed downward in the vertical direction (Z-axis direction), for example. Since the water vapor tends to rise easily in the ambient air, when the high-pressure water vapor 60 is sprayed toward the outer peripheral portion 20b of the holding surface 20a from directly above, the high-pressure water vapor 60 is likely to act on the grinding dust 9 efficiently. .

In addition, the nozzle 58c of the high-pressure water vapor spray unit 58 may face the rotational direction of the table 20 in the sprayed position of the outer peripheral portion 20b of the holding surface 20a of the table 20, and may be relative to Z at a predetermined angle. The axis is tilted. In this case, since the high-pressure water vapor 60 is sprayed from the direction opposite to the traveling direction to the grinding dust 9 that is placed on the outer peripheral portion 20b of the holding surface 20a and moves rotationally, it becomes easy to force the high-pressure water vapor 60 to strongly Acts on grinding dust 9. However, in the polishing apparatus 2 of this embodiment, the direction of the nozzle 58c is not limited to this.

As described above, in the polishing apparatus 2 of the present embodiment, the high-pressure water vapor can be sprayed on the grinding dust 9 fixed to the outer peripheral portion 20b of the holding surface 20a of the table 20, and the grinding dust can be easily removed 9. FIG. 7(B) is a perspective view schematically showing the table 20 from which the grinding dust 9 has been removed from the outer peripheral portion 20b of the holding surface 20a. Since the table 20 whose holding surface 20 a has been cleaned can suck and hold the new workpiece 1 without any problem, the workpiece 1 can be properly ground by the grinding unit 26 .

Next, the grinding|polishing method of this embodiment which grinds the to-be-processed object 1 with the grinding|polishing apparatus 2, and washes the outer peripheral part 20b of the holding surface 20a of the table 20 will be described. FIG. 8(A) is a flowchart schematically showing the flow of each step of the polishing method of the present embodiment.

In the grinding|polishing method of this embodiment, the holding|maintenance step S10 of placing the workpiece 1 on the holding surface 20a and holding it by the work chuck 20 is performed first. FIG. 4 is a perspective view schematically showing the holding step S10.

In the holding step S10 , the X-axis moving table 18 is preliminarily positioned in the carry-in area 22 , and the workpiece 1 positioned by the positioning table 12 at the predetermined position is carried into the holding surface by the workpiece carry-in mechanism 14 . 20a. At this time, the front surface 1a of the workpiece 1 to which the protective tape 3 is attached is oriented toward the holding surface 20a, and the rear surface 1b to be the surface to be polished is oriented upward. Then, the suction source of the table 20 is actuated, and the workpiece 1 is sucked and held by the table 20 . Then, the X-axis moving table 18 is moved to the processing area 24 .

Next, a polishing step S20 is performed, in which the workpiece 1 is polished with a polishing pad while the polishing slurry is supplied to the workpiece 1 held on the work chuck 20 . FIG. 5 is a perspective view schematically showing the grinding step S20. In the grinding step S20, the table 20 and the grinding wheel 44 are rotated around their respective axes. Then, the polishing slurry is supplied from the polishing liquid supply source 48 to the back surface 1b of the workpiece 1 through the polishing liquid supply path 50, and the polishing unit 26 is lowered to bring the polishing pad 44b into contact with the back surface 1b.

At this time, the polishing slurry enters between the polishing pad 44b and the back surface 1b of the workpiece 1, and the back surface 1b side of the workpiece 1 is polished and flattened. The grinding waste generated from the workpiece 1 or the like is taken in by the polishing slurry and transported to the outer peripheral side of the workpiece 1 . In addition, the polishing slurry 56 which has taken in the grinding dust falls to the outer peripheral part 20b of the holding surface 20a of the table 20, and a part of the grinding dust and the like are fixed to the outer peripheral part 20b.

Next, the carrying out step S30 of carrying out the workpiece 1 ground in the grinding step S20 from the table 20 is carried out. In the unloading step S30 , the X-axis moving table 18 is moved to the carrying-out area 22 , the suction and holding of the workpiece 1 by the work chuck 20 is released, and the workpiece unloading mechanism 16 is used to remove the workpiece. The object 1 is conveyed to the rotary cleaning device 52 . Then, the workpiece 1 is cleaned and dried by the rotary cleaning device 52 , and the workpiece 1 is accommodated in the cassette 8 b by the workpiece transfer robot 10 .

In the polishing method of the present embodiment, after the workpiece 1 is unloaded from the work chuck 20 , the grinding dust removal step S40 is performed. The high-pressure water vapor 60 is sprayed from the grinding dust 9 of the outer peripheral portion 20b of the outer peripheral portion 20b, and the grinding dust 9 is removed. Fig. 7(A) is a perspective view schematically showing the grinding dust removal step S40.

In the polishing dust removal step S40 , the nozzle 58 c of the high-pressure water vapor spray unit 58 is directed toward the outer peripheral portion 20 b of the holding surface 20 a of the work chuck 20 . Then, the high-pressure steam 60 is ejected from the nozzle 58c toward the outer peripheral portion 20b of the holding surface 20a. At this time, the table 20 is rotated at a predetermined rotational speed. In this way, the grinding dust 9 fixed to the outer peripheral portion 20 b is softened by being heated and contacted with water, and can be removed by further jetting of the high-pressure water vapor 60 .

In addition, in the grinding dust removal step S40, by spraying water from the porous member constituting the holding surface 20a, the grinding dust 9 removed from the outer peripheral portion 20b of the holding surface 20a can be prevented from entering the porous member. FIG. 7(B) is a perspective view schematically showing the work chuck 20 which has been cleaned and the grinding dust 9 has been removed. As described above, in the polishing method of the present embodiment, the polishing dust 9 can be easily removed from the outer peripheral portion 20b of the holding surface 20a.

Furthermore, in the polishing apparatus 2 of the present embodiment, a high-pressure steam spraying unit 58 for spraying the high-pressure steam 60 toward the holding surface 20a of the work chuck 20 may be provided in the vicinity of the processing area 24 . In addition, in the polishing method of the present embodiment, the polishing dust removal step S40 may be performed while the polishing step S20 is being performed. FIG. 8(B) is a flowchart showing the flow of each step of the polishing method of the present embodiment when the polishing dust removal step S40 is carried out in the polishing step S20.

If the high-pressure steam spraying unit 58 is provided in the vicinity of the machining area 24, when the workpiece 1 is polished by the polishing unit 26, the outer periphery of the holding surface 20a of the table 20 can be sprayed from the high-pressure steam spraying unit 58. The portion 20b injects the high-pressure water vapor 60 . In this case, the polishing slurry can be removed from the outer peripheral portion 20b with the high-pressure steam 60 before the temperature of the polishing slurry containing the polishing debris that has reached the outer peripheral portion 20b is lowered, dried and fixed.

In this case, there is a possibility that the high-pressure water vapor 60 enters between the polishing pad 44b and the back surface 1b of the workpiece 1 and reduces the concentration of the polishing slurry. However, the amount of water supplied from the high-pressure steam injection unit 58 to the holding surface 20a of the work chuck 20 is extremely small compared to, for example, spraying high-pressure water to the outer peripheral portion 20b of the holding surface 20a. Therefore, the injection of the high-pressure water vapor 60 has little effect on the polishing.

In this case, since the new workpiece 1 can be loaded into the table 20 immediately after the workpiece 1 that has been polished is unloaded from the table 20, a plurality of workpieces can be efficiently ground. 1.

In addition, in the polishing method of the present embodiment, the polishing dust removal step S40 may be implemented before the holding step S10. FIG. 8(C) is a flowchart schematically showing the flow of each step of the grinding method of the workpiece in the case where the grinding dust removal step S40 is carried out before the holding step S10.

For example, when a plurality of workpieces 1 are polished by the polishing apparatus 2 in succession, the following problem arises: when a new workpiece 1 is loaded into the work table 20, the problem arises from the problem that the workpiece 1 has been polished by the polishing unit 26 before that. The grinding dust 9 of the workpiece 1 has been fixed to the outer peripheral portion 20b of the holding surface 20a. Therefore, the grinding dust removal step S40 may be performed before performing the holding|maintenance step S10, and the holding surface 20a may be wash|cleaned by the injection|spray of the high-pressure steam 60.

That is, the grinding dust removal step S40 can also be considered as a step performed in advance in order to polish the workpiece 1 appropriately. In addition, the grinding dust removal step S40 can also be considered as a step of removing the grinding dust 9 generated by the grinding of the workpiece 1 in the grinding step S20 and fixed to the outer peripheral portion 20b of the holding surface 20a.

In any case, the polishing method of the present embodiment can exert the following effects on all the workpieces 1 polished by the polishing apparatus 2 : the workpieces 1 are appropriately held by the work chuck 20 and the workpieces are properly polished. Processed product 1. The processing efficiency of the workpiece 1 can also be improved because the man-hours required for replacement or cleaning of the work chuck 20 are reduced, and the stop time of the grinding unit 26 is also reduced.

In addition, this invention is not limited to the description of the said embodiment, Various changes can be made and implemented. For example, in the above-described embodiment, the case where the workpiece 1 is polished by the polishing apparatus 2 for polishing the workpiece 1 has been described, but one aspect of the present invention is not limited to this. For example, the grinding apparatus 2 may have a grinding unit (not shown) for grinding the workpiece 1 in addition to the grinding unit 26 for grinding the workpiece 1 . In addition, the workpiece 1 held by the work chuck 20 may be ground by the grinding unit, and then processed by the grinding unit 26 .

In this case, in addition to the grinding dust 9 , the grinding dust may also accumulate on the outer peripheral portion 20 b of the holding surface 20 a of the table 20 . Even in this case, if the high-pressure water vapor is ejected from the high-pressure water vapor ejection unit 58 toward the outer peripheral portion 20b, the grinding dust and the grinding dust 9 can be removed together. Therefore, when a new workpiece 1 is placed on the table 20 , the grinding dust 9 and the grinding chips do not interfere with the proper holding of the workpiece 1 by the table 20 .

In addition, the structure, method, etc. of the above-mentioned embodiment can be suitably changed and implemented in the range which does not deviate from the objective of this invention.

1: processed object 1a: front 1b: Back 2: Grinding device 3: Protective tape 4: Abutment 4a: Opening 4b: drain 5: Divide the scheduled line 6a, 6b: cassette stage 7: Devices 8a, 8b: cassette 9: Grinding dust 10: Processed object conveying robot 12: Positioning the table 14: Loading mechanism of workpiece (loading arm) 16: The workpiece unloading mechanism (unloading arm) 18: X-axis moving table 20: Work clamp table 20a: Keep Faces 20b: Peripheral part 22: Moving in and out of the area 24: Processing area 26: Grinding unit 28: Support Department 30: Z-axis guide 32: Z-axis moving board 34: Z-axis ball screw 36: Z-axis pulse motor 38: Spindle housing 40: Spindle 42: Mounting seat 44: Grinding Wheel 44a: Wheel seat 44b: Polishing pad 46: Fixtures 48: Grinding fluid supply source 50: Grinding liquid supply path 52: Rotary cleaning device 54: Grinding liquid supply port 56: Grinding slurry 58: High pressure water vapor injection unit 58a: Shaft 58b: Arm 58c: Nozzle 60: High pressure water vapor X,Y,Z: direction S10: Hold Step S20: Grinding step S30: Moving out step S40: grinding dust removal step

FIG. 1 is a perspective view schematically showing a polishing apparatus. FIG. 2 is a perspective view schematically showing a grinding wheel. 3 is a perspective view schematically showing a state in which a protective member is attached to the front surface of a workpiece. FIG. 4 is a perspective view schematically showing a state in which a workpiece is placed on a holding surface of a table. FIG. 5 is a perspective view schematically showing a state of grinding a workpiece. FIG. 6 is a perspective view schematically showing a state in which the ground workpiece is carried out from the holding surface of the table. FIG. 7(A) is a perspective view schematically showing a state in which the outer peripheral portion of the holding surface of the table is cleaned, and FIG. 7(B) is a perspective view schematically showing the table with the holding surface cleaned. FIG. 8(A) is a flowchart showing the flow of each step of an example of a method for polishing a workpiece, and FIG. 8(B) is a flowchart showing the flow of each step in another example of the method for polishing a workpiece, FIG. 8(C) is a flowchart showing the flow of each step of another example of the polishing method of the workpiece.

9: Grinding dust

20: Work clamp table

20a: Keep Faces

20b: Peripheral part

58: High pressure water vapor injection unit

58a: Shaft

58b: Arm

58c: Nozzle

60: High pressure water vapor

Claims (2)

A grinding device is a grinding device for grinding a workpiece, characterized in that it comprises: A work jig, which has a holding surface and attracts and holds the workpiece placed on the holding surface; A grinding unit for grinding the workpiece with a polishing pad while supplying a polishing slurry to the workpiece held by the work chuck; and The high-pressure water vapor spraying unit is provided with a nozzle for spraying high-pressure water vapor on the holding surface of the work chuck, The abrasive dust deposited on the outer peripheral portion of the holding surface can be removed from the holding surface by injecting high-pressure water vapor from the high-pressure water vapor spraying means. A grinding method is a grinding method using a grinding device, wherein the grinding device is provided with: a work chuck for sucking and holding a workpiece placed on a holding surface; The retained object to be processed is supplied with a polishing slurry while the object to be processed is ground with a polishing pad, and the aforementioned grinding method is characterized by comprising the following steps: Holding step, the workpiece is placed on the holding surface and held by the work chuck; Grinding step, while supplying abrasive slurry to the workpiece held by the work chuck, grinding the workpiece with the polishing pad; a carrying-out step, carrying out the workpiece that has been ground in the grinding step from the work chuck; and In the grinding dust removal step, high-pressure water vapor is sprayed on the grinding dust accumulated on the outer peripheral portion of the holding surface of the work chuck to remove the grinding dust.

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