JP7187119B2 - Grinding device and dressing board type discrimination method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a grinding apparatus for grinding a wafer formed of a semiconductor or the like with a grinding wheel, and a discriminating method for discriminating the type of dressing board that recovers the grinding ability of the grinding wheel.

In the manufacturing process of device chips used in electronic devices such as mobile phones and computers, first, multiple devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integration) are formed on the surface of wafers made of semiconductors. do. Next, the wafer is divided for each device to form individual device chips. In recent years, in order to form thin device chips, the wafer is ground from the back side to thin it before the wafer is divided.

Grinding of the wafer is performed in a grinding machine. The grinding apparatus has a holding table that holds a wafer and a grinding unit that grinds the wafer, the grinding unit having a spindle and a grinding wheel attached to the lower end of the spindle. A grinding wheel is attached to the underside of the grinding wheel. A grinding wheel and a holding table for holding a wafer are rotated around respective rotation axes substantially parallel to each other, and the grinding wheel is lowered to bring the grinding wheel into contact with the wafer, thereby grinding the wafer. be.

A grinding wheel is formed by dispersing abrasive grains such as diamond in a binder. Abrasive grains are appropriately exposed from the bonding material on the contact surface of the grinding wheel that contacts the wafer, and the wafer is ground when the abrasive grains come into contact with the wafer. As the grinding of the wafer progresses, the abrasive grains wear out or fall off from the bonding material, but the bonding material is also consumed and new abrasive grains are exposed to the contact surface one after another, so the grinding ability of the grinding wheel is maintained. be done. This action is called self-sharpening.

When an abnormality such as clogging or erosion occurs in the grinding wheel during grinding of the workpiece, and the grinding power of the grinding wheel cannot be sufficiently maintained only by the action of self-sharpening, the grinding wheel is used. to grind the dressing board. The operation of grinding this dressing board is called dressing. When the dressing is carried out, the binding material of the grinding wheel is actively consumed and the action of self-sharpening is promoted, thereby recovering the grinding ability of the grinding wheel.

Here, there is known a grinding apparatus that automatically performs dressing when it is detected that a grinding wheel has an abnormality (see Patent Document 1). The grinding apparatus further has a function of monitoring the grinding state of the workpiece and automatically performing truing for aligning the height of the grinding wheel when an abnormality occurs in the machining result.

By the way, there are various types of grinding wheels that differ in the material of the binding material and the size and distribution of the abrasive grains. Then, a type of grinding wheel suitable for processing is selected according to the material of the workpiece and the content of the grinding process, and is mounted on the grinding apparatus.

JP-A-9-29630

A dressing board used for dressing a grinding wheel or the like is formed by dispersing abrasive grains in a binder. There are also various types of dressing boards that differ in the material of the binding material, the size of the abrasive grains, and the state of distribution. Used for dressing.

For this reason, various types of dressing boards corresponding to various types of grinding wheels are prepared in factories or the like where grinding machines are operated. Then, the user or manager of the grinding machine selects a dressing board of a type corresponding to the type of grinding wheel to be dressed when performing dressing, and carries it into the holding table of the grinding machine.

However, when dressing the grinding wheel, there is a case where an inappropriate type of dressing board is erroneously carried into the holding table of the grinding wheel. If an inappropriate type of dressing board is ground, not only the grinding wheel cannot be properly dressed, but also the grinding wheel and the grinding device may be damaged. In this case, it is necessary to stop the grinding device for an unexpectedly long period of time, which significantly reduces the operating efficiency of the grinding device. Therefore, there is a demand for identifying the type of dressing board carried into the holding table.

The present invention has been made in view of such problems, and its object is to provide a grinding apparatus capable of discriminating the type of dressing board carried into a holding table, and a discriminating method capable of discriminating the type of dressing board. That is.

According to one aspect of the present invention, a grinding unit having a grinding wheel having a grinding wheel on its lower surface and capable of grinding a workpiece with the grinding wheel, and a dressing member included in a dressing board used for dressing the grinding wheel. a detection unit that can be used to calculate the outer diameter size of the dressing board, and a control unit, the control unit storing the outer diameter size of the dressing member included in the dressing board for each type of dressing board An outer diameter size calculation unit that calculates the outer diameter size of the dressing member included in the dressing board carried into the detection unit using the detection unit, and the outer diameter of the dressing member calculated by the outer diameter size calculation unit and a discriminating unit that discriminates the type of the dressing board carried into the detection unit based on the size of the dressing board.

Preferably, the detection unit can measure the thickness of each part of the dressing board, and the outer diameter size calculation part causes the detection unit to measure the thickness of each part of the dressing board carried into the detection unit, The position of the outer periphery of the dressing member is determined from the relationship between the position of the dressing board where the thickness was measured and the measured thickness of each part, and the outer diameter size of the dressing member is calculated.

According to another aspect of the present invention, there is provided a discrimination method for discriminating the type of dressing board used for dressing a grinding wheel mounted on a grinding apparatus, wherein the dressing board for each type of dressing board has A preparation step of preparing a storage unit in which the outer diameter size of the dressing member included is stored, a loading step of loading the dressing board into a detection unit that can be used to calculate the outer diameter size of the dressing member included in the dressing board; an outer diameter size calculating step of calculating an outer diameter size of a dressing member included in the dressing board carried into the detection unit; and calculating the outer diameter size of the dressing member calculated in the outer diameter size calculating step. and a determination step of determining the type of the dressing board carried into the detection unit by collating with the outer diameter size of the dressing member for each type of dressing board stored in a storage unit. A method of determination is provided.

Preferably, after the determination step, the method further comprises a determination step of determining whether or not the type of dressing board determined in the determination step is suitable for dressing the grinding wheel.

Further, preferably, the detection unit can measure the thickness of each part of the dressing board carried into the detection unit, and the outer diameter size calculating step measures the thickness of each part of the dressing board carried into the detection unit. Perimeter detection for detecting the position of the perimeter of the dressing member from the relationship between the thickness measurement step of measuring the thickness, the thickness of each part measured in the thickness measurement step, and the position where the thickness was measured. and calculating the outer diameter size of the dressing member from the position of the outer circumference of the dressing member detected in the outer circumference detecting step.

A dressing board used for dressing a grinding wheel has a dressing member and a support substrate that supports the dressing member. The outer diameter size of the dressing member is determined for each type of dressing board. Therefore, in the grinding apparatus and determination method according to one aspect of the present invention, the outer diameter size of the dressing member of the dressing board is calculated. Then, the type of the dressing board is specified from the calculated outer diameter size of the dressing member.

If the type of dressing board can be determined, it can be determined whether or not the dressing board is suitable for the grinding wheel to be dressed. Therefore, when an inappropriate type of dressing board is brought in, it is possible to detect that the dressing board is inappropriate before dressing the grinding wheel, thereby preventing inappropriate dressing from being performed. .

Accordingly, one aspect of the present invention provides a grinding apparatus capable of discriminating the type of dressing board carried into the holding table, and a discriminating method capable of discriminating the type of dressing board.

It is a perspective view which shows the structure of a grinding apparatus typically. FIG. 2(A) is a cross-sectional view schematically showing an example of a dressing board, FIG. 2(B) is a cross-sectional view schematically showing another example of the dressing board, and FIG. , and a cross-sectional view schematically showing still another example of a dressing board. It is a flowchart which shows the flow of the discrimination|determination method which concerns on this embodiment. It is a perspective view which shows an example of a detection unit typically.

An embodiment according to the present invention will be described with reference to the drawings. The grinding apparatus and determination method according to the present embodiment relate to, for example, a grinding apparatus that grinds a wafer having a semiconductor device formed on the front surface thereof from the rear surface side to thin the wafer to a predetermined thickness. FIG. 1 is a perspective view schematically showing the configuration of a grinding device 2 according to this embodiment.

The wafer 1 to be ground by the grinding device 2 is, for example, Si (silicon), SiC (silicon carbide), GaN (gallium nitride), GaAs (gallium arsenide), or other materials such as semiconductors, or sapphire. , a substantially disk-shaped substrate made of a material such as glass, quartz, or the like. Examples of the glass include alkali glass, alkali-free glass, soda-lime glass, lead glass, borosilicate glass, and quartz glass.

A plurality of devices (not shown) such as ICs (Integrated Circuits) and LSIs (Large Scale Integrations) are formed on the front surface 1a of the wafer 1 . When the wafer 1 is thinned by grinding the wafer 1 from the back surface 1b side by the grinder 2, and the wafer 1 is divided for each device, individual device chips can be formed.

In the grinding device 2, the back surface 1b of the wafer 1 is ground while the back surface 1b side of the wafer 1 is exposed upward. A tape-like protective member 3 is attached to the front surface 1a of the wafer 1 to protect the devices formed on the front surface 1a of the wafer 1 when the wafer 1 is ground. The wafers 1 are accommodated in, for example, a cassette 28a capable of accommodating a plurality of wafers 1, are transported, and are loaded into the grinding apparatus 2. As shown in FIG.

Next, the grinding device 2 according to this embodiment will be described in detail. The grinding device 2 includes a base 4 that supports each component. Cassette mounting tables 26a and 26b are fixed to the front end of the base 4. As shown in FIG. For example, a cassette 28a containing wafers 1 before grinding is mounted on the cassette mounting table 26a, and a cassette 28b for containing wafers 1 after grinding is mounted on the cassette mounting table 26b.

A wafer transfer robot 30 is mounted on the base 4 at a position adjacent to the cassette mounting tables 26a and 26b. The wafer transfer robot 30 unloads the wafer 1 from the cassette 28a placed on the cassette mounting table 26a, and transfers the wafer 1 to the positioning table 32 provided on the base 4 at a position adjacent to the wafer transfer robot 30. do.

The positioning table 32 has a plurality of positioning pins arranged in a ring. When the wafer 1 is placed on the central placement area, the positioning table 32 positions the wafer 1 at a predetermined position by interlocking and moving the respective positioning pins radially inward.

A loading arm 34 and an unloading arm 36 are provided at positions adjacent to the positioning table 32 on the upper surface of the base 4 . The wafer 1 positioned at the predetermined position by the positioning table 32 is transferred by the loading arm 34 .

A disk-shaped turntable 6 is provided on the central upper surface of the base 4 so as to be rotatable in the horizontal plane. On the upper surface of the turntable 6 are provided, for example, three holding tables 8 which are circumferentially spaced apart from each other by 120 degrees. Each holding table 8 can be moved by rotating the turntable 6 .

Each holding table 8 has a suction path (not shown) with one end connected to a suction source (not shown), and the other end of the suction path is connected to a holding surface 8a on the holding table 8. . The holding surface 8a is made of, for example, a porous member. The holding table 8 activates the suction source when an object to be held is placed on the holding surface 8a, and applies the generated negative pressure to the object to be held through the porous member, thereby lifting the object to be held. Can hold suction.

The loading/unloading of the wafer 1 to/from the holding table 8 is performed in the wafer loading/unloading area of the turntable 6 . In the wafer loading/unloading area, the loading arm 34 can load the wafer 1 onto the holding table 8 and the unloading arm 36 can unload the wafer 1 from the holding table 8 . After the wafer 1 is loaded by the loading arm 34 onto the holding table 8 positioned in the wafer loading/unloading area, the turntable 6 is rotated to move the holding table 8 to the next rough grinding area.

A first grinding unit 10a for rough grinding the back surface 1b side of the wafer 1 held on the holding table 8 positioned in the rough grinding area is arranged outside the turntable 6 on the upper surface of the rear side of the base 4. there is After rough grinding of the wafer 1 by the first grinding unit 10a, the turntable 6 is rotated to move the holding table 8 to the finish grinding area adjacent to the rough grinding area.

A second grinding unit 10b for finish grinding the back surface 1b side of the wafer 1 held by the holding table 8 positioned in the finish grinding area is arranged outside the turntable 6 on the upper surface of the rear side of the base 4. there is After finishing grinding of the wafer 1 by the second grinding unit 10b, the turntable 6 is rotated to return the holding table 8 to the wafer loading/unloading area, and the unloading arm 36 moves the wafer 1 onto the holding table. Carry out from 8.

A spinner cleaning device 38 for cleaning and spin-drying the ground wafer 1 is arranged near the unloading arm 36 on the upper surface of the base 4 and the wafer transfer robot 30 . The wafer 1 cleaned and dried by the spinner cleaning device 38 is transferred from the spinner cleaning device 38 by the wafer transfer robot 30 and accommodated in the cassette 28b mounted on the cassette mounting table 26b.

Columns 22a and 22b are erected on the rear portion of the base 4. As shown in FIG. A grinding feed unit 24a that supports the first grinding unit 10a movably along the vertical direction is arranged on the front surface of the column 22a. A grinding feed unit 24b that supports the second grinding unit 10b so as to be movable in the vertical direction is arranged on the front surface of the column 22b.

The first grinding unit 10a supported by the grinding feed unit 24a includes a spindle 14a extending in the vertical direction and a spindle motor 12a connected to the upper end of the spindle 14a. The second grinding unit 10b supported by the grinding feed unit 24b includes a spindle 14b extending in the vertical direction and a spindle motor 12b connected to the upper end of the spindle 14b.

A disk-shaped wheel mount 16a is provided at the lower end of the spindle 14a, and a grinding wheel 18a is fixed to the lower surface of the wheel mount 16a. A plurality of grinding wheels 20a arranged in an annular shape are attached to the lower surface of the grinding wheel 18a. A disk-shaped wheel mount 16b is provided at the lower end of the spindle 14b, and a grinding wheel 18b is fixed to the lower surface of the wheel mount 16b. A plurality of grinding wheels 20b arranged in an annular shape are attached to the lower surface of the grinding wheel 18b.

When the spindle motor 12a is actuated to rotate the spindle 14a in the vertical direction, the grinding wheel 18a rotates and the grinding stone 20a moves on the annular orbit. Then, when the grinding feed unit 24a is operated to lower the first grinding unit 10a and bring the grinding wheel 20a into contact with the back surface 1b of the wafer 1 held on the holding table 8, the wafer 1 is moved from the back surface 1b side. be ground.

Further, when the spindle motor 12b is actuated to rotate the spindle 14b in the vertical direction, the grinding wheel 18b rotates and the grinding wheel 20b moves on the annular orbit. Then, when the grinding feed unit 24b is operated to lower the second grinding unit 10b and bring the grinding wheel 20b into contact with the back surface 1b of the wafer 1 held on the holding table 8, the wafer 1 is moved from the back surface 1b side. be ground.

In the grinding of the wafer 1 using the first grinding unit 10a, the wafer 1 is roughly ground while the grinding feed unit 24a feeds the wafer 1 at a relatively high speed. In rough grinding by the first grinding unit 10a, most of the thickness of the wafer 1 ground and removed by the grinding device 2 is efficiently removed.

In the grinding of the wafer 1 using the second grinding unit 10b, the wafer 1 is finish ground while the grinding feed unit 24b feeds the wafer 1 at a relatively low speed. In the finish grinding by the second grinding unit 10b, the wafer 1 is ground to a predetermined finish thickness with high precision.

A first thickness measuring unit 40 for measuring the thickness of the wafer 1 roughly ground by the first grinding unit 10a is arranged on the upper surface of the base 4 near the first grinding unit 10a. there is The first thickness measuring unit 40 includes, for example, a post vertically installed outside the turntable 6 and extending from the upper end of the post above the holding table 8 positioned in the rough grinding area. and two probes. Each probe is vertically movable with respect to the post.

A probe placed relatively on the upper side contacts the back surface 1b of the wafer 1 to measure the height of the back surface 1b. Further, the probe arranged relatively lower contacts the holding surface 8a of the holding table 8 and measures the height of the holding surface 8a. The first thickness measurement unit 40 can calculate the thickness of the wafer 1 from the difference between the height of the back surface 1 b of the wafer 1 and the height of the holding surface 8 a of the holding table 8 . However, the first thickness measuring unit 40 is not limited to a contact-type thickness measuring instrument, and may be another type of thickness measuring instrument.

Near the second grinding unit 10b on the upper surface of the base 4, there is a non-contact second thickness measuring unit 42 for measuring the thickness of the wafer 1 being finish ground by the second grinding unit 10b. are arranged. The second thickness measuring unit 42 includes, for example, a post vertically installed outside the turntable 6 and extending from the upper end of the post above the holding table 8 positioned in the finish grinding area. and an arm. A cylindrical head portion is provided at the tip of the arm portion.

The second thickness measurement unit 42 measures the height of the back surface 1b of the wafer 1, for example, by irradiating the back surface 1b of the wafer 1 with a laser beam and detecting the reflected laser beam. It is a measurement unit (spectral interference laser displacement meter). Alternatively, the second thickness measuring unit 42 transmits ultrasonic waves to the back surface 1b of the wafer 1, detects the ultrasonic waves reflected by the back surface 1b of the wafer 1, and measures the height of the back surface 1b of the wafer 1. It is a sonic thickness measurement unit. However, the second thickness measurement unit 42 is not limited to this.

The first grinding unit 10a refers to the thickness of the wafer 1 measured by the first thickness measurement unit 40, and roughly grinds the wafer 1 until the wafer 1 reaches a predetermined thickness. The second grinding unit 10b also refers to the thickness of the wafer 1 measured by the second thickness measurement unit 42, and finish grinds the wafer 1 until the wafer 1 reaches the final thickness.

The grinding wheels 20a and 20b are formed by dispersing abrasive grains of diamond or the like in a binder, for example. Abrasive grains are appropriately exposed from the bonding material on the contact surfaces of the grinding wheels 20a and 20b that contact the wafer 1, and the wafer 1 is ground by the exposed abrasive grains coming into contact with the wafer 1. As the grinding of the wafer 1 progresses, the abrasive grains are worn or fall off from the bonding material. Grinding ability is maintained. This action is called self-sharpening.

When an abnormality such as clogging or blinding occurs in the grinding wheels 20a and 20b and the grinding ability of the grinding wheels 20a and 20b cannot be sufficiently maintained only by the action of self-sharpening, dressing boards are attached to the grinding wheels 20a and 20b. be ground. The operation of grinding this dressing board is called dressing. When the dressing is carried out, the binding material of the grinding wheels 20a and 20b is actively consumed and the action of self-sharpening is promoted, thereby recovering the grinding ability of the grinding wheels 20a and 20b.

There are various types of grinding wheels 20a and 20b that differ in the material of the binding material, the distribution state of abrasive grains, and the like. Then, a type of grinding wheel suitable for processing is selected according to the material of the workpiece and the details of the grinding process, and mounted on the grinding device 2 . For example, the grinding wheel 20a used for rough grinding of the wafer 1 and the grinding wheel 20b used for finish grinding of the wafer 1 may be of different types.

FIG. 4 shows an example of a dressing board used for dressing the grinding wheels 20a and 20b. FIG. 4 shows a perspective view schematically showing the dressing board 5. As shown in FIG. The dressing board 5 includes a support base 7 and a disk-shaped dressing member 9 supported by the support base 7 .

The support base 7 is a disk-shaped member made of resin such as vinyl chloride, and its outer diameter corresponds to the diameter of the holding surface 8 a of the holding table 8 . When the dressing board 5 is carried onto the holding surface 8 a and the suction holding mechanism of the holding table 8 is operated, a negative pressure acts on the support base 7 to hold the dressing board 5 on the holding table 8 .

The support base 7 of each dressing board 5 is sized to cover the holding surface 8a of the holding table 8 so as not to leak the negative pressure generated by the suction source of the holding table 8. Regardless, it is assumed to be roughly constant.

A dressing member 9 supported by the support base 7 is formed by dispersing abrasive grains in a binder. When dressing the grinding wheels 20a and 20b, the dressing member 9 is ground by the grinding wheels 20a and 20b.

There are various types of dressing boards 5 that differ in the material of the bonding material of the dressing member 9 and the distribution state of abrasive grains. An appropriate type of dressing board 5 that matches the type of grinding wheels 20a and 20b to be dressed is selected and used for dressing. Here, the outer diameter size of the dressing member 9 is determined according to the type of dressing board 5 .

Therefore, in the grinding apparatus 2 according to the present embodiment, the outer diameter size of the dressing member 9 of the dressing board 5 used when dressing the grinding wheels 20a and 20b is calculated. Then, the type of dressing board 5 is determined from the outer diameter size of the dressing member 9 . In this case, it can be determined whether or not the dressing board 5 is suitable for dressing the grinding wheels 20a and 20b to be dressed.

A detection unit 46 is assembled at a position adjacent to the wafer transfer robot 30 on the base 4 of the grinding device 2 . The detection unit 46 is used to calculate the outer diameter size of the dressing member 9 included in the dressing board 5 when identifying the type of the dressing board 5 .

The detection unit 46 is, for example, a thickness measurement unit capable of measuring the thickness of each part of the object. When the dressing board 5 is carried into the detection unit 46, the thickness of each part of the dressing board 5 can be measured. FIG. 4 schematically shows a perspective view of the detection unit 46 and the dressing board 5 carried into the detection unit 46. As shown in FIG.

The detection unit 46 includes, for example, a stage 46a on which the dressing board 5 is placed, and a thickness measuring section 52 that can be used to calculate the outer diameter size of the dressing member 9 of the dressing board 5 placed on the stage 46a. A support portion 46b is erected at the rear end portion of the stage 46a, and a moving mechanism 48 capable of moving the thickness measuring portion 52 is housed inside the support portion 46b.

The detection unit 46 further includes a support member 50 extending along the Y-axis direction and having a thickness measuring section 52 at its tip. When the moving mechanism 48 is operated, the supporting member 50 and the thickness measuring section 52 provided at the tip of the supporting member 50 move along the X-axis direction. The thickness measuring unit 52 can measure the thickness of the dressing board 5 without contact.

For example, the detection unit 46 measures the height of the dressing board 5 by emitting a laser beam from the thickness measuring unit 52, irradiating the dressing board 5 with the laser beam, and detecting the reflected laser beam. It is a laser thickness measurement unit (spectral interference laser displacement meter). Alternatively, it is an ultrasonic thickness measurement unit that transmits ultrasonic waves from the thickness measurement unit 52 to the dressing board 5 and detects the ultrasonic waves reflected by the dressing board 5 to measure the height of the dressing board 5 .

The detection unit 46 measures the thickness of each part of the dressing board 5 while operating the moving mechanism 48 to move the thickness measuring part 52 above the dressing board 5 along the X-axis direction.

The dressing board 5 has a relatively thick portion where the dressing member 9 exists and a relatively thin portion where the dressing member 9 does not exist. Therefore, the boundary between the portion of the dressing board 5 observed to be relatively thick and the portion observed to be relatively thin is the position of the outer periphery of the dressing member 9 . Once the position of the outer circumference of the dressing member 9 is known, the outer diameter size of the dressing member 9 can be calculated. That is, the detection unit 46 is used for calculating the outer diameter size of the dressing element 9 .

However, the detection unit 46 is not limited to this. For example, the detection unit 46 may be an imaging camera capable of imaging the upper surface of the dressing board 5 carried in. When the detection unit 46 is an imaging camera, the outer diameter size of the dressing member 9 is determined by imaging the upper surface of the dressing board 5 to form a captured image, and detecting the position of the outer circumference of the dressing member 9 from the captured image. can be calculated.

Next, the control unit 44 provided in the grinding device 2 will be described. The control unit 44 is connected to each component of the grinding apparatus 2 and has a function of controlling each component. For example, the control unit 44 is configured by a computer connected to the grinding machine 2 . The computer has a CPU, a memory, a storage device, and the like. Processing conditions for processing the wafer 1 are registered in advance in the control unit 44, and the control unit 44 controls each component according to the processing conditions.

In addition, the control unit 44 uses a storage unit 44b that stores the outer diameter size of the dressing member 9 for each product type, and a detection unit 46 that detects the outer diameter size of the dressing member 9 held as an object to be held on the holding table 8. and an outer diameter size calculator 44a that calculates the Further, the control unit 44 includes a discriminating section 44c that discriminates the type of the dressing board 5 from the calculated outer diameter size of the dressing member 9 .

Preferably, the control unit 44 determines whether or not the type of the dressing board 5 determined by the determination unit 44c is suitable for dressing the grinding wheels 20a and 20b to be dressed. Includes portion 44d. Each configuration of the control unit 44 will be described below. The outer diameter size calculator 44 a calculates the outer diameter size of the dressing member 9 included in the dressing board 5 using the detection unit 46 .

For example, when the detection unit 46 measures the height of each area of the dressing board 5a schematically shown in FIG. 2A, the area where the dressing member 9a exists is detected as a relatively high area. . Also, the area where the dressing member 9a does not exist is detected as a relatively low area. In FIG. 2A, a relatively thick dashed line arrow is shown above the location detected as the high area, and a relatively thin dashed line is shown above the location detected as the low area. showing an arrow.

In this case, the boundary between the high area and the low area of the dressing board 5a is the position of the outer periphery of the dressing member 9a. Then, the outer diameter size calculator 44a calculates the outer diameter size 11a of the dressing member 9a from the outer peripheral position of the dressing member 9a detected by the detection unit 46 .

Here, the outer diameter size of the dressing member 9 is, for example, a numerical value represented by a diameter when the dressing member 9 is viewed from above. Alternatively, the outer diameter size may be represented by numerical values such as the radius of the dressing member 9, the radius of curvature, and the area. The outer diameter size is a numerical value indicating the size of the dressing member 9, and is determined according to the type of dressing board. Therefore, when the outer diameter size of the dressing member 9 is calculated, the type of the dressing board 5 can be determined.

In addition, when the detection unit 46 used for calculating the outer diameter size of the dressing member 9 is an imaging camera, the outer diameter size calculation unit 44a analyzes the captured image of the dressing board 5 acquired by the imaging camera. . Then, the position of the outer circumference of the dressing member 9 is detected, and the outer diameter size of the dressing member 9 is calculated.

The storage unit 44b stores the outer diameter size of the dressing member 9 included in the dressing board 5 for each type of the dressing board 5 used for dressing the grinding wheels 20a and 20b. The outer diameter size of the dressing member 9 of each dressing board 5 is registered in advance in the storage unit 44b by the manufacturer of the grinding device 2, the administrator, or the like. Furthermore, the types of grinding wheels that can be dressed using the dressing board 5 of each type may be registered in the storage unit 44b. The storage section 44b provides each section of the control unit 44 with this information.

When discriminating the type of the dressing board, first, the outer diameter size calculator 44a is caused to calculate the outer diameter size of the dressing member 9 of the dressing board 5, and the outer diameter size is obtained from the outer diameter size calculator 44a. . Then, the determination unit 44c acquires information on the type of the dressing board 5 corresponding to the outer diameter size of the dressing member 9 calculated by the outer diameter size calculation unit 44a from the storage unit 44b.

Then, the determination unit 44c determines that the type of the dressing board 5 for which the outer diameter size of the dressing member 9 is calculated using the detection unit 46 is the type of the dressing board 5 related to the information sent from the storage unit 44b. discriminate. Then, the determination unit 44c sends information about the determined type of the dressing board 5 to the determination unit 44d. In the control unit 44, information on the types of the grinding wheels 20a and 20b to be dressed is registered in advance, and the determination unit 44d determines whether the types of the dressing board 5 held in the holding table 8 are the grinding wheels 20a and 20b. Determine whether it is suitable for dressing of 20b.

When the determination unit 44d determines that the type of the dressing board 5 is suitable for dressing the grinding wheels 20a and 20b to be dressed, the control unit 44 controls the grinding unit to dressing. On the other hand, the control unit 44 does not dress the grinding wheels 20a and 20b when the determination unit 44d determines that the type of dressing board is not suitable for dressing.

The grinding machine 2 may be provided with a display unit, a warning lamp, or a warning alarm for notifying the administrator or user of various warnings. A manager or the like may be notified.

The grinding apparatus 2 according to the present embodiment can thus determine the type of the dressing board 5 and determine whether the dressing board 5 is suitable before dressing the grinding wheels 20a and 20b. Therefore, for example, an inappropriate type of dressing board is not conveyed to the holding table 8, and there is no fear of dressing the grinding wheels 20a and 20b with the dressing board.

Next, a determination method for determining the type of dressing board according to this embodiment will be described. The discrimination method according to the present embodiment is a discrimination method for discriminating the type of dressing board used for dressing a grinding wheel mounted on a grinding apparatus. For example, the determination method is implemented in the grinding apparatus 2 shown in FIG. FIG. 3 is a flow chart showing the flow of the determination method.

In the determination method, first, a preparation step S1 is performed. In the preparation step S1, the storage unit 44b storing the outer diameter size of the dressing member 9 included in the dressing board 5 for each kind of the dressing board 5 is prepared. The storage unit 44b is provided in, for example, a control unit 44 that controls each component of the grinding device 2. As shown in FIG.

In the preparation step S1, for example, the outer diameter size of the dressing member 9 included in the dressing board 5 is registered in the storage section 44b of the control unit 44 for each type of the dressing board 5. FIG. Alternatively, in the preparation step S1, the storage unit 44b in which the outer diameter size of the dressing member 9 included in the dressing board 5 is registered in advance for each type of the dressing board 5 is prepared.

Next, in the determination method, a loading step S2 of loading the dressing board 5 into the detection unit 46 that can be used to calculate the outer diameter size of the dressing member 9 included in the dressing board 5 is performed.

Next, in the determination method, an outer diameter size calculation step S3 of calculating the outer diameter size of the dressing member 9 included in the dressing board 5 carried into the detection unit 46 is performed. For example, the detection unit 46 is a thickness measurement unit capable of measuring the thickness of each portion of the dressing board 5 carried into the detection unit 46 . The detection unit 46 is used to measure the thickness of each area of the dressing board 5, and the position of the outer periphery of the dressing member 9 is specified from the thickness distribution. Then, the outer diameter size of the dressing member 9 is calculated from the specified outer peripheral position of the dressing member 9 .

For example, the outer diameter size calculation step S3 includes a thickness measurement step of measuring the thickness of each part of the dressing board 5 carried into the detection unit 46, an outer circumference detection step of detecting the position of the outer circumference of the dressing member 9, including. In the outer circumference detecting step, the position of the outer circumference of the dressing member 9 is detected from the relationship between the thickness of each portion measured in the thickness measuring step and the position where the thickness was measured. Then, the outer diameter size of the dressing member 9 is calculated from the position of the outer circumference of the dressing member 9 detected in the outer circumference detecting step.

After performing the outer diameter size calculation step S3, a discrimination step S4 of discriminating the type of the dressing board 5 is carried out. In the determination step S4, the calculated outer diameter size is collated with the outer diameter size of the dressing member for each type of dressing board stored in the storage unit 44b, thereby determining the dressing board carried into the detection unit 46. 5 varieties are discriminated.

The outer diameter size calculation step S3 and determination step S4 will be further described with reference to FIGS. 2(A), 2(B), and 2(C).

2(A), 2(B), and 2(C) schematically show cross-sectional views of examples of dressing boards 5a, 5b, and 5c, respectively. The dressing boards 5a, 5b, 5c respectively have support bases 7a, 7b, 7c and dressing members 9a, 9b, 9c supported by the support bases 7a, 7b, 7c. The dressing member 9a has an outer diameter size 11a, the dressing member 9b has an outer diameter size 11b and the dressing member 9c has an outer diameter size 11c.

A case will be described where it is calculated in the outer diameter size calculation step S3 that the dressing member of the dressing board whose type is to be discriminated has the outer diameter size 11b. In this case, in the determination step S4, it is determined that the type of the dressing board is the type of the dressing board 5b shown in FIG. 2(B). Further, a case where it is calculated in the outer diameter size calculation step S3 that the dressing member of the dressing board whose type is to be determined has the outer diameter size 11c will be described. In this case, in the determination step S4, the type of the dressing board is determined to be the type of the dressing board 5c shown in FIG. 2(C).

In the determination method according to the present embodiment, after performing the determination step S4, it is determined whether or not the type of dressing board determined in the determination step S4 is suitable for dressing the grinding wheel mounted on the grinding device 2. A determination step S5 for determination may be further implemented. For example, in the control unit 44 of the grinding apparatus 2, information on the type of grinding wheel or information on the type of dressing board suitable for dressing the grinding wheel is registered.

Then, in determination step S5, it is determined whether or not the type of dressing board determined in determination step S4 is suitable for dressing the grinding wheel. In the determination step S5, when it is determined that the type of the dressing board is suitable for dressing the grinding wheel to be dressed, the dressing is performed on the grinding wheel with the dressing board after the determination step S5. Further steps may be performed.

On the other hand, if it is determined in the determination step S5 that the type of dressing board is not suitable for dressing the target grinding wheel, a warning step is performed to warn the user of the grinding device 2 or the like to that effect. may

As described above, according to the grinding apparatus and determination method according to the present embodiment, the type of dressing board used for dressing can be determined before dressing the grinding wheel. Therefore, when the dressing board is not suitable for dressing the grinding wheel, the user of the grinding apparatus can be warned without performing dressing. Therefore, it is possible to prevent inappropriate dressing from being carried out, prevent malfunctions of the grinding device and the grinding wheel, and as a result improve the efficiency of grinding by the grinding device.

It should be noted that the present invention is not limited to the description of the above embodiments, and can be implemented with various modifications. For example, in the above embodiment, a case has been described in which the outer diameter size of the dressing member of the dressing board is calculated to discriminate the type of the dressing board. However, for example, there may be a plurality of types of dressing boards having the same outer diameter size of the dressing member. In this case, even if the outer diameter size of the dressing member can be calculated, the type of dressing board cannot be specified completely.

However, even in this case, the types of dressing boards 5 carried into the detection unit 46 can be narrowed down to several candidates. Therefore, when the candidates listed as the types of dressing boards carried into the detection unit 46 do not include a type of dressing board suitable for dressing the grinding wheel to be dressed, the execution of dressing can be stopped.

In one aspect of the invention, it is thus not necessary for the type of dressing board to be completely specific to one type. That is, in one aspect of the present invention, determining the type of dressing board includes narrowing the range of candidates for the type of dressing board.

For example, in a dressing board used for dressing the grinding wheel 20a used for rough grinding of the wafer 1, the outer diameter size of the dressing member may be unified. At the same time, in the dressing board used for dressing the grinding wheel 20b used for finish grinding of the wafer 1, the outer diameter size of the dressing member may be unified.

In addition, one aspect of the present invention produces an effect when the outer diameter size of the dressing member of the dressing board used for dressing the grinding wheel 20a and the grinding wheel 20b is different.

For example, when trying to dress the grinding wheel 20b with a dressing board used for dressing the grinding wheel 20a, according to one aspect of the present invention, it is possible to detect that the type of dressing board is inappropriate. Further, when dressing the grinding wheel 20a with the dressing board used for dressing the grinding wheel 20b, according to one aspect of the present invention, it is possible to detect that the type of dressing board is inappropriate. Even in these cases, inappropriate dressing can be prevented.

Furthermore, in the above-described embodiment, the case where the detection unit 46 is used when calculating the outer diameter size of the dressing member of the dressing board has been described, but one aspect of the present invention is not limited to this. That is, for example, the first thickness measurement unit 40 or the second thickness measurement unit 42 may be used when calculating the outer diameter size of the dressing member of the dressing board. In this case, the detection unit 46 may not be provided on the base 4 of the grinding device 2 .

In addition, the structures, methods, and the like according to the above-described embodiments can be modified as appropriate without departing from the scope of the present invention.

1 wafer 1a front surface 1b back surface 3 protective member 5, 5a, 5b, 5c dressing board 7, 7a, 7b, 7c support base 9, 9a, 9b, 9c dressing member 11a, 11b, 11c outer diameter size 2 grinding device 4 units Table 6 Turntable 8 Holding table 8a Holding surfaces 10a, 10b Grinding units 12a, 12b Spindle motors 14a, 14b Spindles 16a, 16b Wheel mounts 18a, 18b Grinding wheels 20a, 20b Grinding wheels 22a, 22b Columns 24a, 24b Grinding feed unit 26a , 26b Cassette mounting table 28a, 28b Cassette 30 Wafer transfer robot 32 Positioning table 34 Loading arm 36 Unloading arm 38 Spinner cleaning device 40, 42 Thickness measurement unit 44 Control unit 44a Outer diameter size calculator 44b Storage unit 44c Discrimination unit 44d Judgment part 46 detection unit 46a stage 46b support part 48 movement mechanism 50 support member 52 thickness measurement part

Claims (5)

a grinding unit having a grinding wheel having a grinding wheel on its lower surface and capable of grinding a workpiece with the grinding wheel;
a detection unit that can be used to calculate the outer diameter size of a dressing member included in a dressing board used for dressing the grinding wheel;
a control unit;
The control unit is
a storage unit that stores the outer diameter size of the dressing member included in the dressing board for each type of dressing board;
an outer diameter size calculation unit that uses the detection unit to calculate the outer diameter size of the dressing member included in the dressing board carried into the detection unit;
a determination unit that determines the type of the dressing board carried into the detection unit from the outer diameter size of the dressing member calculated by the outer diameter size calculation unit;
A grinding device comprising: The detection unit can measure the thickness of each part of the dressing board,
The outer diameter size calculation unit causes the detection unit to measure the thickness of each part of the dressing board carried into the detection unit, and the position of the dressing board where the thickness measurement is performed and the measured thickness of each part 2. The grinding apparatus according to claim 1, wherein the position of the outer periphery of the dressing member is determined from the relationship between the thickness and the size of the outer diameter of the dressing member. A discrimination method for discriminating the type of dressing board used for dressing a grinding wheel mounted on a grinding device,
a preparation step of preparing a storage unit in which outer diameter sizes of dressing members included in the dressing board are stored for each type of dressing board;
a loading step of loading the dressing board into a detection unit that can be used to calculate the outer diameter size of the dressing members included in the dressing board;
An outer diameter size calculation step of calculating the outer diameter size of the dressing member included in the dressing board carried into the detection unit;
The outer diameter size of the dressing member calculated in the outer diameter size calculating step is compared with the outer diameter size of the dressing member for each type of dressing board stored in the storage unit, and the dressing member is carried into the detection unit. and a determining step of determining the type of the dressing board that has been made. 4. The determination method according to claim 3, further comprising, after the determination step, a determination step of determining whether or not the type of the dressing board determined in the determination step is suitable for dressing the grinding wheel. . The detection unit can measure the thickness of each part of the dressing board carried into the detection unit,
The outer diameter size calculation step includes:
A thickness measurement step of measuring the thickness of each part of the dressing board carried into the detection unit;
an outer circumference detection step of detecting the position of the outer circumference of the dressing member from the relationship between the thickness of each part measured in the thickness measurement step and the position where the thickness was measured,
4. The determination method according to claim 3, wherein the outer diameter size of the dressing member is calculated from the position of the outer circumference of the dressing member detected in the outer circumference detecting step.

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