JP4890697B2 - Polishing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polishing apparatus for polishing a workpiece such as a semiconductor wafer held on a chuck table.
[0002]
[Prior art]
In the semiconductor device manufacturing process, a large number of rectangular regions are defined by cutting lines called streets arranged in a lattice pattern on the surface of a substantially wafer-shaped semiconductor wafer, and a semiconductor circuit is formed in each of the rectangular regions. Individual semiconductor chips are formed by separating the semiconductor wafer formed with such a large number of semiconductor circuits along the streets. In order to reduce the size and weight of a semiconductor chip, the semiconductor wafer is usually ground to a predetermined thickness by cutting the semiconductor wafer along the streets and separating the individual rectangular regions. Forming. A polishing apparatus for polishing the back surface of such a semiconductor wafer polishes a chuck table having a mounting surface on which a workpiece is to be mounted, and a workpiece to be mounted on the mounting surface of the chuck table. And a polishing unit feeding mechanism for moving the polishing unit in a direction perpendicular to the mounting surface of the chuck table. In such a polishing apparatus, polishing is performed by pressing the polishing unit against the back surface of the semiconductor wafer, which is a workpiece, at a predetermined feed rate. However, the processing surface is surfaced due to the relationship between the polishing capability and the feed rate of the polishing unit. May burn or be damaged.
[0003]
In order to solve the above-mentioned problem, the present applicant is provided with a polishing resistance value detecting means for detecting a polishing resistance value generated when the workpiece is polished, and the polishing resistance value detected by the polishing resistance value detecting means is adjusted. JP-A-2001-138219 proposes a polishing apparatus which controls the feed of the polishing unit based on this and maintains the polishing resistance value within a predetermined range.
[0004]
[Problems to be solved by the invention]
Thus, when the polishing resistance value, that is, the polishing load is large, the surface burn does not necessarily occur. According to the study of the present inventor, when the frictional heat between the workpiece and the polishing tool reaches 300 ° C., for example, the surface burns. It was found that burning occurred. In particular, when using a felt grindstone in which abrasive grains are dispersed in a felt and fixed with an appropriate bonding agent as a polishing tool, and dry polishing is performed, the frictional heat between the workpiece and the polishing tool increases and surface burn is promoted. I found out.
[0005]
The present invention has been made in view of the above facts, and a main technical problem thereof is to provide a polishing apparatus that controls the feed rate of a polishing unit in response to frictional heat between a workpiece and a polishing tool. .
[0006]
[Means for Solving the Problems]
In order to solve the above main technical problem, according to the present invention, a chuck table having a mounting surface on which a workpiece is to be mounted, and a workpiece to be mounted on the mounting surface of the chuck table. In a polishing apparatus comprising: a polishing unit provided with a polishing tool for polishing a polishing unit; and a polishing unit feed mechanism for moving the polishing unit back and forth in a direction perpendicular to the mounting surface of the chuck table.
Temperature detecting means for detecting the temperature in the vicinity of the mounting surface of the chuck table;
Control means for controlling the polishing unit feeding mechanism based on a detection signal from the temperature detection means,
The temperature detection means includes a plurality of temperature sensors disposed in different radial regions of the chuck table,
The control means advances the polishing unit feed mechanism by a predetermined amount when the maximum detected temperature detected by the plurality of temperature sensors is lower than a first set value, and is detected by the plurality of temperature sensors. The maximum detected temperature is Higher than the first set value A polishing apparatus is provided in which the polishing unit feed mechanism is retracted by a predetermined amount when higher than a second set value.
In order to solve the main technical problem, according to the present invention, a chuck table having a mounting surface on which a workpiece is mounted, and a workpiece mounted on the mounting surface of the chuck table. In a polishing apparatus comprising: a polishing unit comprising a polishing tool for polishing an object; and a polishing unit feed mechanism for moving the polishing unit forward and backward in a direction perpendicular to the mounting surface of the chuck table;
Temperature detecting means for detecting the temperature in the vicinity of the mounting surface of the chuck table;
Control means for controlling the polishing unit feeding mechanism based on a detection signal from the temperature detection means,
The control means advances the polishing unit feed mechanism by a predetermined amount when the temperature detected by the temperature detection means is lower than the first set value, and the temperature detected by the temperature detection means is higher than the first set value. If it is greater than or equal to the second set value, the polishing unit feed mechanism is retracted by a predetermined amount,
A polishing apparatus is provided, wherein the control means retracts the polishing unit feeding mechanism when the temperature detected by the temperature detection means is equal to or higher than a third set value higher than the second set value. The
[0009]
Further, according to the present invention, there is provided a polishing apparatus in which the polishing tool comprises a felt grindstone in which abrasive grains are dispersed in felt and fixed with an appropriate bond agent, and a workpiece is polished in a dry manner.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a polishing apparatus configured according to the present invention will be described in detail with reference to the accompanying drawings.
[0011]
FIG. 1 is a perspective view of a polishing apparatus according to the present invention.
The polishing apparatus comprises an apparatus housing, generally designated 2. The apparatus housing 2 includes a rectangular parallelepiped main portion 21 that extends elongated and an upright wall 22 that is provided at a rear end portion (upper right end in FIG. 1) of the main portion 21 and extends substantially vertically upward. Yes. A pair of guide rails 221 and 221 extending in the vertical direction are provided on the front surface of the upright wall 22. The polishing unit 3 is mounted on the pair of guide rails 221 and 221 so as to be movable in the vertical direction.
[0012]
The polishing unit 3 includes a moving base 31 and a spindle unit 32 attached to the moving base 31. The movable base 31 is provided with a pair of legs 311 and 311 extending in the vertical direction on both sides of the rear surface. The pair of legs 311 and 311 is slidably engaged with the pair of guide rails 221 and 221. Guided grooves 312 and 312 are formed. As described above, a support portion 313 protruding forward is provided on the front surface of the movable base 31 slidably mounted on the pair of guide rails 221 and 221 provided on the upright wall 22. The spindle unit 32 is attached to the support portion 313.
[0013]
The spindle unit 32 includes a spindle housing 321 mounted on the support portion 313, a rotary spindle 322 rotatably disposed on the spindle housing 321, and a servo motor as a drive source for rotationally driving the rotary spindle 322. 323 (M1), and the output shaft of the servo motor 323 (M1) is connected to the rotary spindle 322 via a reduction mechanism (not shown). The lower end of the rotary spindle 322 protrudes downward beyond the lower end of the spindle housing 321, and a polishing tool 325 is attached to the lower end of the rotary spindle 322. More specifically, a disc-shaped mounting member 324 is fixed to the lower end of the rotary spindle 322, and a plurality of through holes (not shown) are formed in the mounting member 324 at intervals in the circumferential direction. Has been. As illustrated in FIGS. 3 and 4, the polishing tool 325 includes a disk-shaped support member 326 and a disk-shaped polishing member 327. The support member 326 is formed with a plurality of blind screw holes 326a extending downward from the upper surface thereof at intervals in the circumferential direction. The lower surface of the support member 326 forms a circular support surface, and the polishing member 327 is joined to the circular support surface of the support member 326 by an appropriate adhesive such as an epoxy resin adhesive. In the illustrated embodiment, the abrasive member 327 is a felt grindstone in which abrasive grains are dispersed in the felt and fixed with an appropriate bond agent. The detailed description of the structure of the polishing member 327 itself made of the felt grindstone has already been described in detail in the specification and drawings of Japanese Patent Application No. 2001-93397 proposed by the present applicant. The description is omitted in the book. The polishing tool 325 is positioned on the lower surface of the mounting member 324 fixed to the lower end of the rotary spindle 322, and the blind screw hole 326a formed in the support member 326 of the polishing tool 325 through the through hole formed in the mounting member 324. The fastening tool 325 is attached to the attachment member 324 by screwing the fastening bolt 328 onto the attachment member 324.
[0014]
Referring back to FIG. 1, the polishing apparatus in the illustrated embodiment moves the polishing unit 3 up and down along the pair of guide rails 221 and 221 (in a direction perpendicular to a mounting surface of a chuck table described later). ) Is provided with a polishing unit feeding mechanism 4. The polishing unit feed mechanism 4 includes a male screw rod 41 disposed on the front side of the upright wall 22 and extending substantially vertically. The male screw rod 41 is rotatably supported by bearing members 42 and 43 whose upper end and lower end are attached to the upright wall 22. The upper bearing member 42 is provided with a pulse motor 44 (M2) as a drive source for rotationally driving the male screw rod 41. The output shaft of the pulse motor 44 (M2) is connected to the male screw rod 41 in a transmission manner. Has been. A connecting portion (not shown) that protrudes rearward from the center portion in the width direction is also formed on the rear surface of the movable base 31, and a through female screw hole that extends in the vertical direction is formed in the connecting portion, The male screw rod 41 is screwed into the female screw hole. Accordingly, when the pulse motor 44 (M2) rotates forward, the moving base 31, that is, the polishing unit 3, is lowered or advanced, and when the pulse motor 44 (M2) reverses, the moving base 31, that is, the polishing unit 3, is raised or moved backward. .
[0015]
The polishing apparatus in the illustrated embodiment includes polishing unit position detecting means 5 for detecting the movement position of the polishing unit 3 as shown in FIG. The polishing unit position detecting means 5 includes a linear scale 51 disposed in the upright wall 22 in parallel with the male screw rod 41, and a detector 52 that is attached to the moving base 31 and detects a detected line of the linear scale 51. (LIS). The detector 52 (LIS) may be a photoelectric detector known per se, and generates a pulse signal in response to detection of detection lines (for example, formed at intervals of 1 μm) of the linear scale 51. A signal is sent to the control means described later. The upright wall 22 has a long hole that allows the detector 52 (LIS) to move.
[0016]
1 and FIG. 2, the description will be continued with reference to FIG. 1 and FIG. 2. A substantially rectangular immersive portion 211 is formed on the rear half of the main portion 21 of the housing 2. It is arranged. The chuck table mechanism 6 includes a support base 61 and a disk-shaped chuck table 62 disposed on the support base 61 so as to be rotatable about a rotation center axis extending substantially vertically. The support base 61 has a pair of guide rails 23 (in FIG. 2, one of the guide rails 23 extending in the direction indicated by the arrows 23a and 23b in the front-rear direction (the direction perpendicular to the front surface of the upright wall 22). (Only the guide rail is shown).
[0017]
The chuck table 62 has a placement surface 621 for placing a workpiece on the upper surface, and is rotatably supported on the support base 61 by support means 63. A rotation shaft 622 is mounted on the lower surface of the chuck table 62 at the center thereof. The chuck table 62 is made of an appropriate porous material such as porous ceramics, and is connected to suction means (not shown). Therefore, the workpiece W placed on the placement surface 621 is sucked and held by selectively communicating the chuck table 62 with a suction means (not shown).
[0018]
The chuck table 62 is provided with temperature detecting means 64 (TDS) for detecting the temperature in the vicinity of the mounting surface 621. The temperature detecting means 64 (TDS) is composed of three temperature sensors 64a, 64b and 64c arranged in different radial regions of the chuck table 62 in the illustrated embodiment. The voltage signals output from the temperature sensors 64a, 64b, and 64c are converted into digital signals by an A / D converter (not shown) and sent to control means described later.
[0019]
The support means 63 constituting the chuck table mechanism 6 includes three support pillars 631 (only two are shown in FIG. 2) disposed on the support base 61 and the support pillars 631. The chuck table 62 is rotatably supported via a ball bearing 633 on the support plate 632. A hole 632a through which the rotating shaft 622 is inserted is provided at the center of the support plate 632. On the support base 61 below the support plate 632, a servo motor 65 (M3) as a drive source for rotationally driving the chuck table 62 is disposed. The output shaft of the servo motor 65 (M3) is connected in transmission to the rotating shaft 622 of the chuck table 62.
[0020]
The polishing apparatus in the illustrated embodiment includes a chuck table moving mechanism 66 that moves the chuck table mechanism 6 along the pair of guide rails 23 in the directions indicated by arrows 23a and 23b, as shown in FIG. The chuck table moving mechanism 66 includes a male screw rod 661 disposed between the pair of guide rails 23 and extending in parallel with the guide rails 23. Both ends of the male screw rod 661 are rotatably supported by bearing members 662 and 663 attached by connecting a pair of guide rails 23. The front bearing member 662 is provided with a servo motor 664 (M4) as a drive source for rotationally driving the male screw rod 661. The output shaft of the servo motor 664 (M4) is connected to the male screw rod 661 for transmission. Has been. A female screw block 665 having a through female screw hole is attached to the front end (left end in FIG. 2) of the support base 61, and the male screw rod 661 is screwed into the through female screw hole of the female screw block 665. Therefore, when the servo motor 664 (M4) rotates forward, the support base 61, that is, the chuck table mechanism 6 moves in the direction indicated by the arrow 23a. When the servo motor 664 (M4) reverses, the support base 61, that is, the chuck table mechanism 6 moves. It is moved in the direction indicated by the arrow 23b. The chuck table mechanism 6 that is moved in the directions indicated by the arrows 23a and 23b is selectively applied to the workpiece loading / unloading area 24 and the polishing area 25 that are positioned at intervals in the directions indicated by the arrows 23a and 23b. Positioned. The chuck table mechanism 6 is reciprocated in the direction indicated by the arrows 23a and 23b over a predetermined range in the polishing region 25.
[0021]
On both sides of the chuck table moving mechanism 66 in the moving direction, as shown in FIG. 1, bellow means 71 and 72 having a reverse cross-sectional shape and covering the male screw rod 661 and the like are attached. The bellows means 71 and 72 can be formed from any suitable material such as campus cloth. The front end of the bellows means 71 is fixed to the front wall of the immersion portion 211, and the rear end is fixed to the front end surface of the support base 61 of the chuck table mechanism 6. The front end of the bellows means 72 is fixed to the rear end surface of the support base 61 of the chuck table mechanism 6, and the rear end is fixed to the front surface of the upright wall 22 of the apparatus housing 2. When the chuck table mechanism 6 is moved in the direction indicated by the arrow 23a, the bellows means 71 is expanded and the bellows means 72 is contracted, and when the chuck table mechanism 6 is moved in the direction indicated by the arrow 23b, the bellows means. 71 is contracted and the bellows means 72 is extended.
[0022]
The description will be continued based on FIG. 1. On the front half of the main portion 21 of the apparatus housing 2, a first cassette 11, a second cassette 12, a workpiece temporary placing means 13, and a cleaning means are provided. 14, a workpiece conveying means 15, a workpiece carrying-in means 16 and a workpiece carrying-out means 17 are arranged. The first cassette 11 stores a workpiece before polishing and is placed in a cassette carry-in area in the main portion 21 of the apparatus housing 2. The second cassette 12 is placed in a cassette unloading area in the main portion 21 of the apparatus housing 2 and stores a workpiece after polishing. The workpiece temporary placing means 13 is disposed between the first cassette 11 and the workpiece loading / unloading area 24, and temporarily places the workpiece before polishing. The cleaning means 14 is disposed between the workpiece loading / unloading area 24 and the second cassette 12, and cleans the workpiece after polishing. Workpiece conveying means 15 is disposed between the first cassette 11 and the second cassette 12, and the work piece stored in the first cassette 11 is carried out to the workpiece temporary placement means 13. At the same time, the workpiece cleaned by the cleaning means 14 is conveyed to the second cassette 12. The workpiece carrying-in means 16 is disposed between the workpiece temporary placing means 13 and the workpiece carrying-in / out area 24, and is placed on the workpiece temporary placing means 13 before polishing. The workpiece is transferred onto the chuck table 62 of the chuck table mechanism 6 positioned in the workpiece loading / unloading area 24. The workpiece unloading means 17 is disposed between the workpiece loading / unloading area 24 and the cleaning means 14, and is polished on a chuck table 62 positioned in the workpiece loading / unloading area 24. The processed workpiece is conveyed to the cleaning means 14.
[0023]
The workpiece accommodated in the first cassette 11 is a semiconductor wafer having a front surface mounted on an annular frame via a protective tape (therefore, the semiconductor wafer is positioned on the upper surface), or a support substrate (sub A semiconductor wafer having a front surface mounted on a straight surface (therefore, the back surface of the semiconductor wafer is located on the upper side) may be used. The first cassette 11 containing the semiconductor wafer as such a workpiece is placed in a predetermined cassette carry-in area in the main portion 21 of the apparatus housing 2. Then, when all the semiconductor wafers before polishing that have been accommodated in the first cassette 11 placed in the cassette carry-in area are unloaded, a new cassette that accommodates a plurality of semiconductor wafers instead of the empty cassette 11 11 is manually placed in the cassette carry-in area. On the other hand, when a predetermined number of polished semiconductor wafers are loaded into the second cassette 12 placed in a predetermined cassette unloading area in the main portion 21 of the apparatus housing 2, the second cassette 12 is manually moved. It is unloaded and a new empty second cassette 12 is placed.
[0024]
The polishing apparatus in the illustrated embodiment includes a control means 10 as shown in FIG. The control means 10 is constituted by a microcomputer, and a central processing unit (CPU) 101 that performs arithmetic processing according to a control program, a read-only memory (ROM) 102 that stores a control program, etc., and a read / write that stores arithmetic results and the like. A random access memory (RAM) 103, a timer (T) 104, an input interface 105, and an output interface 106. The input interface 105 of the control means 10 configured in this way has three detectors 52 (LIS) of the linear scale 51 constituting the polishing unit position detection means 5 and three pieces constituting the temperature detection means 64 (TDS). The signals from the temperature sensors 64a, 64b, 64c, etc. are input. Further, from the output interface 106, the servo motor 323 (M1), the pulse motor 44 (M2), the servo motor 65 (M3), the servo motor 664 (M4), the cleaning means 14, the workpiece conveying means 15, and the workpiece. A control signal is output to the article carry-in means 16, the work-piece carry-out means 17, and the like.
[0025]
Next, the processing operation of the above-described polishing apparatus will be briefly described with reference to FIG.
The semiconductor wafer as the workpiece before polishing, which is accommodated in the first cassette 11, is conveyed by the vertical movement and the advance / retreat operation of the workpiece conveying means 15 and is placed on the workpiece temporary placing means 13. . The semiconductor wafer mounted on the workpiece temporary mounting means 13 is positioned in the workpiece loading / unloading area 24 by the turning operation of the workpiece loading means 16 after being centered here. It is placed on the chuck table 62 of the chuck table mechanism 6. The semiconductor wafer placed on the chuck table 62 is sucked and held on the chuck table 62 by suction means (not shown). Thereafter, the chuck table mechanism 6 is moved in the direction indicated by the arrow 23 a and positioned in the polishing area 25. In the polishing region 25, the chuck table 62 holding the semiconductor wafer is rotated, and the polishing member 327 of the polishing tool 325 being driven to rotate is pressed against the back surface of the semiconductor wafer on the chuck table 62, Then, the chuck table mechanism 6 is reciprocated over a predetermined range in the directions indicated by the arrows 23a and 23b. Thus, the back surface of the semiconductor wafer is dry-polished by the action of the polishing member 327, and residual processing strain is removed.
[0026]
When the polishing is finished, the polishing tool 325 is separated upward from the back surface of the semiconductor wafer, and the chuck table mechanism 6 is moved to the workpiece loading / unloading area 24 in the direction indicated by the arrow 23b. Thereafter, the suction holding of the polished semiconductor wafer on the chuck table 62 is released, and the semiconductor wafer released from the suction holding is unloaded by the workpiece unloading means 17 and conveyed to the cleaning means 14. Cleaning means 14. The transferred semiconductor wafer is then cleaned and then stored in a predetermined position of the second cassette 12 by the workpiece transfer means 15.
[0027]
In the illustrated embodiment, the control shown in the flowchart of FIG. 5 is executed in order to polish the semiconductor wafer, which is a workpiece, without causing surface burn. The routine of FIG. 5 is stored in advance in a read only memory (ROM) 102 of the control means 10 and is repeatedly executed by the central processing unit (CPU) 101 every predetermined time. In the read only memory (ROM) 102, the first set value T1, the second set value T2 higher than the first set value T1, and the second set value T2 as shown in FIG. A higher third set value T3 is stored as a comparison value. Note that the first set value T1 is set to, for example, 50 ° C. at an allowable temperature considering the polishing efficiency. The second set value T2 is a dangerous temperature at which surface burning may occur if a temperature higher than this is continued, and is set to 200 ° C., for example. The third set value T3 is a surface burning temperature at which surface burning occurs, and is set to 250 ° C., for example.
[0028]
Hereinafter, the control of the polishing unit feeding mechanism 4 during the polishing operation will be described with reference to the flowchart of FIG.
In step S1, the control means 10 first reads temperature signals Ta, Tb, Tc from the three temperature sensors 64a, 64b, 64c constituting the temperature detection means 64 (TDS) for detecting the temperature of the chuck table 62. If the temperature signals Ta, Tb, Tc are read in step S1, the control means 10 proceeds to step S2 and selects the maximum value (Tmax) from Ta, Tb, Tc.
[0029]
If the maximum value (Tmax) of the temperature of the chuck table 62 is selected in step S2, the control means 10 proceeds to step S3 and checks whether the maximum value (Tmax) is equal to or greater than the third set value T3. If the maximum value (Tmax) is equal to or greater than the third set value T3, the control means 10 determines that surface burning occurs, and proceeds to step S4 to drive the pulse motor 44 (M2) of the polishing unit feed mechanism 4 in reverse. To do. As a result, the polishing unit 3 is raised and positioned at the retracted position, and the polishing operation is temporarily interrupted.
[0030]
If the maximum value (Tmax) of the temperature of the chuck table 62 is lower than the third set value T3 in step S3, the control means 10 proceeds to step S5 and the maximum value (Tmax) of the temperature of the chuck table 62 is the first value. It is checked whether it is higher than the set value T2 of 2. If the maximum value (Tmax) is higher than the second set value T2, the control means 10 determines that surface burn will occur if polishing is continued in this state, and proceeds to step S6, where the pulse motor of the polishing unit feed mechanism 4 is operated. 44 (M2) is driven in reverse by a predetermined number of pulses. As a result, the polishing unit 3 is raised or retracted by a predetermined amount, and the pressing force of the polishing tool 325 to the semiconductor wafer is reduced.
[0031]
If the maximum value (Tmax) of the temperature of the chuck table 62 is not more than the second set value T2 in step S5, the control means 10 proceeds to step S7 and the maximum value (Tmax) of the temperature of the chuck table 62 is the first value. It is checked whether it is lower than the set value T1 of 1. When the maximum value (Tmax) is lower than the first set value T1, the control means 10 determines that the pressing force of the polishing tool 325 to the semiconductor wafer is small and the polishing efficiency is low, and the process proceeds to step S8 to send the polishing unit. The pulse motor 44 (M2) of the mechanism 4 is driven forward by a predetermined number of pulses. As a result, the polishing unit 3 is lowered or advanced by a predetermined amount, and the pressing force of the polishing tool 325 to the semiconductor wafer is increased.
[0032]
If the maximum temperature (Tmax) of the chuck table 62 is equal to or higher than the first set value T1 in step S7, the control means 10 sets the maximum value (Tmax) of the chuck table 62 to the first setting. It is determined that it is within an appropriate range between the value T1 and the second set value T2, and the polishing operation is performed while maintaining the polishing unit 3 in the current state.
[0033]
As described above, in the illustrated embodiment, the polishing unit is fed so that the maximum value (Tmax) of the temperature of the chuck table 62 falls within an appropriate range between the first set value T1 and the second set value T2. Since the mechanism 4 is controlled, it is possible to improve the polishing efficiency while preventing the surface burn of the workpiece. Further, in the illustrated embodiment, when the maximum value (Tmax) of the temperature of the chuck table 62 is equal to or higher than a third set value T3 that is a temperature at which surface burning occurs, the polishing unit 3 is positioned at the retracted position. Since the polishing operation is temporarily interrupted, it is possible to reliably prevent the surface burn of the workpiece.
[0034]
As mentioned above, although this invention was demonstrated based on embodiment of illustration, this invention is not limited only to embodiment. For example, in the embodiment, three temperature sensors 64a, 64b, and 64c are used as temperature detecting means 64 (TDS) for detecting the temperature of the chuck table, and based on the maximum temperature detected by the three temperature sensors. Although an example of control is shown, control may be performed based on an average value of temperatures detected by a plurality of temperature sensors.
[0035]
【Effect of the invention】
In the polishing apparatus according to the present invention, the temperature of the chuck table holding the workpiece is detected, and the polishing unit feed mechanism is set so that the temperature falls within an appropriate range between the first set value and the second set value. Therefore, the polishing efficiency can be improved while preventing the surface burn of the workpiece.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a polishing apparatus constructed according to the present invention.
FIG. 2 is a schematic configuration diagram showing a main part of the polishing apparatus shown in FIG. 1;
3 is a perspective view showing a polishing tool used in the polishing apparatus shown in FIG. 1. FIG.
4 is a perspective view showing a state of the polishing tool shown in FIG. 3 as viewed from the lower surface side.
FIG. 5 is a flowchart showing an operation procedure of a control unit equipped in the polishing apparatus shown in FIG. 1;
6 is an explanatory diagram showing a relationship between each set value stored in a control unit equipped in the polishing apparatus shown in FIG. 1 and the temperature of the chuck table. FIG.
[Explanation of symbols]
2: Device housing
3: Polishing unit
31: Moving base
32: Spindle unit
321: Spindle housing
322: Rotating spindle
323: Servo motor (M1)
325: Polishing tool
4: Polishing unit feed mechanism
44: Pulse motor (M2)
5: Polishing unit position detection means
51: Linear scale
52: Detector (LIS)
6: Chuck table mechanism
61: Support base
62: Chuck table
64: Temperature detection means (TDS)
65: Servo motor (M3)
66: Chuck table moving mechanism
664: Servo motor (M4)
71, 72: Bellows means
10: Control means
11: First cassette
12: Second cassette
13: Workpiece temporary placement means
14: Cleaning means
15: Workpiece conveying means
16: Workpiece carrying means
17: Workpiece unloading means

Claims (3)

A chuck table having a mounting surface for mounting a workpiece, a polishing unit having a polishing tool for polishing the workpiece mounted on the mounting surface of the chuck table, and the polishing In a polishing apparatus comprising: a polishing unit feed mechanism that moves a unit back and forth in a direction perpendicular to the mounting surface of the chuck table;
Temperature detecting means for detecting the temperature in the vicinity of the mounting surface of the chuck table;
Control means for controlling the polishing unit feeding mechanism based on a detection signal from the temperature detection means,
The temperature detection means includes a plurality of temperature sensors disposed in different radial regions of the chuck table,
The control means advances the polishing unit feed mechanism by a predetermined amount when the maximum detected temperature detected by the plurality of temperature sensors is lower than a first set value, and is detected by the plurality of temperature sensors. polishing apparatus maximum value of the detected temperature as the allowed to a predetermined amount retracting the polishing unit feeding mechanism is higher than a second set value higher than the first set value, characterized in that. A chuck table having a mounting surface for mounting a workpiece, a polishing unit having a polishing tool for polishing the workpiece mounted on the mounting surface of the chuck table, and the polishing In a polishing apparatus comprising: a polishing unit feed mechanism that moves a unit back and forth in a direction perpendicular to the mounting surface of the chuck table;
Temperature detecting means for detecting the temperature in the vicinity of the mounting surface of the chuck table;
Control means for controlling the polishing unit feeding mechanism based on a detection signal from the temperature detection means,
The control means advances the polishing unit feed mechanism by a predetermined amount when the temperature detected by the temperature detection means is lower than the first set value, and the temperature detected by the temperature detection means is higher than the first set value. If it is greater than or equal to the second set value, the polishing unit feed mechanism is retracted by a predetermined amount,
The polishing apparatus, wherein the control means retracts the polishing unit feeding mechanism when the temperature detected by the temperature detecting means is equal to or higher than a third set value higher than the second set value. The polishing apparatus according to claim 1, wherein the polishing tool is made of a felt grindstone in which abrasive grains are dispersed in felt and fixed with an appropriate bonding agent, and the workpiece is polished by a dry method.

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