JP6602725B2 - Window structure for workpiece thickness measurement - Google Patents

Description

  The present invention relates to a workpiece thickness measuring window structure.

  Conventionally, a polishing apparatus for polishing a workpiece in order to flatten both surfaces or one surface of a thin plate-shaped workpiece such as a silicon wafer, glass, ceramics, and quartz has been used.

  In general, a thickness measuring device for measuring the thickness of the workpiece during polishing of the workpiece is connected to the polishing apparatus. As this plate thickness measuring device, for example, a device that receives reflected light reflected by irradiating a workpiece with infrared rays and measures the plate thickness of the workpiece is known.

  The surface plate of the polishing apparatus is provided with a measurement window structure (workpiece thickness measurement window structure) as shown in Patent Document 1, for example. This window structure for measurement is formed by attaching a window member to a measurement hole penetrating the front and back surfaces of the surface plate of the polishing apparatus. The window member includes a cylindrical portion having one end inserted into the measurement hole, a translucent window plate provided at one end of the cylindrical portion, and a fixed portion provided at the other end of the cylindrical portion. The fixed part is fixed to the surface of the surface plate. The measurement window structure of Patent Document 1 configured as described above transmits infrared rays emitted from the plate thickness measuring device through the cylindrical portion to the window plate and irradiates the surface of the workpiece, The reflected light reflected from the back surface is transmitted through the window plate, passed through the cylindrical portion, and received by the plate thickness measuring device.

JP 2013-223908 A

  However, in the measurement window structure of Patent Document 1, since the fixed portion holds the other end of the cylindrical portion of the window member and is fixed to the surface of the surface plate, the window member is unexpectedly caused by vibration of the surface plate. May tilt. In this case, since the window member cannot transmit the infrared rays and reflected light of the amount necessary for measuring the thickness of the workpiece, the accuracy of the measured value of the thickness obtained by the thickness measuring device is lowered. Therefore, there is a demand for a workpiece thickness measuring window structure that can stably fix the window member to the surface of the surface plate.

  The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a window thickness measurement window structure for a workpiece that can stably fix a window member to the surface of a surface plate. To do.

  The workpiece thickness measurement window structure of the present invention includes a measurement hole penetrating the front and back surfaces of a surface plate of a polishing apparatus for polishing a thin plate-shaped workpiece, a cylindrical portion having one end inserted into the measurement hole, and the cylinder A window member having a translucent window plate provided at one end of the cylindrical portion and a fixed member fixed to the surface of the surface plate by holding the outer peripheral surface of the other end side of the cylindrical portion in surface contact And a section.

  In the window thickness measuring window structure for a workpiece according to the present invention, the fixed portion is held so as to be in surface contact with the outer peripheral surface on the other end side of the cylindrical portion. As a result, the fixed portion has a wider range for holding the cylindrical portion of the window member than in the prior art, and thus it is possible to continue holding the cylindrical portion of the window member while maintaining a pre-adjusted angle. Therefore, the plate thickness measurement window structure of the present invention can stably fix the window member to the surface of the surface plate.

It is a schematic diagram which shows the structure of the grinding | polishing system to which the window thickness measurement window structure of the workpiece | work which concerns on one embodiment of this invention was applied. It is a longitudinal cross-sectional view of the plate | board structure for plate | board thickness measurement of the workpiece | work which concerns on one embodiment of this invention. It is a top view of the sleeve which comprises the plate | board thickness measurement window structure of the workpiece | work of the embodiment. FIG. 4 is a front view of the sleeve of FIG. 3. It is a longitudinal cross-sectional view of the color which comprises the plate | board thickness measurement window structure of the workpiece | work of the embodiment. It is a top view of the housing which comprises the plate | board thickness measurement window structure of the workpiece | work of the embodiment. It is AA sectional drawing and BB sectional drawing of FIG. It is a top view of the cap which comprises the plate | board thickness measurement window structure of the workpiece | work of the embodiment. It is CC sectional drawing and DD sectional drawing of FIG. It is a top view of the cover which comprises the plate | board thickness measurement window structure of the workpiece | work of the embodiment. It is the schematic perspective view which looked at the cover of FIG. 10 from the outer peripheral side of the upper surface plate. It is a schematic bottom view of the cover of FIG. It is a figure explaining the plate | board thickness measuring method of the workpiece | work using the plate | board thickness measurement window structure of the workpiece | work of the embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram showing a configuration of a polishing system 101 to which a workpiece thickness measuring window structure 1 according to an embodiment of the present invention is applied. The polishing system 101 includes a polishing apparatus 201 and a plate thickness measuring apparatus 301 connected to the polishing apparatus 201. The configuration of the polishing apparatus 201 and the plate thickness measuring apparatus 301 will be briefly described with reference to FIG.

  The polishing apparatus 201 is for polishing both surfaces of a thin plate-like workpiece W using an abrasive. The polishing apparatus 201 includes an upper surface plate 211 and a lower surface plate 212 that are rotationally driven, and a control unit 213 that controls driving of the upper surface plate 211 and the lower surface plate 212.

  A polishing pad (not shown) is attached to the lower surface 211b of the upper surface plate 211 and the upper surface 212a of the lower surface plate 212, respectively. A carrier 214 is disposed between both polishing pads and placed on the lower surface plate 212. The carrier 214 holds a work W. The polishing apparatus 201 is configured to rotate both the upper surface plate 211 and the lower surface plate 212 to polish both surfaces of the workpiece W while supplying an abrasive with both polishing pads.

  The plate thickness measuring device 301 measures the plate thickness Wt of the workpiece W being polished. The plate thickness measuring device 301 includes a measuring device main body 311, a laser head 312 and a data analysis unit 313 connected to the measuring device main body 311.

  Although not shown, the measurement apparatus main body 311 includes an oscillator that oscillates an infrared ray Ra and a measuring instrument that measures the interference intensity of the reflected light Rb (see FIG. 13). The laser head 312 is configured to irradiate the surface Wa of the workpiece W being polished with the infrared ray Ra oscillated from an oscillator, and to receive the reflected light Rb reflected by the surface Wa and the back surface Wb of the workpiece W. .

  The data analysis unit 313 has an input side connected to the measuring device of the measuring apparatus main body 311 and an output side connected to the control unit 213 of the polishing apparatus 201. The data analysis unit 313 is configured to receive a measurement value of the interference intensity from the measuring instrument and calculate the thickness Wt of the workpiece W in real time based on the measurement value. Further, the data analysis unit 313 is configured to be able to send the thickness Wt of the workpiece W obtained by calculation to the control unit 213. The control unit 213 is configured to control the rotational drive of the upper surface plate 211 and the lower surface plate 212.

  The upper surface plate 211 is provided with a plate thickness measuring window structure 1 for a workpiece according to the present embodiment. As shown in FIG. 13, the workpiece thickness measurement window structure 1 irradiates the front surface Wa of the work W through the infrared ray Ra emitted from the laser head 312, and is reflected by the front surface Wa and the back surface Wb of the work W. Used to cause the laser head 312 to receive light through the light Rb. The configuration of the workpiece thickness measuring window structure 1 will be specifically described below.

  FIG. 2 is a longitudinal sectional view of the workpiece thickness measuring window structure 1. This workpiece thickness measurement window structure 1 includes a measurement hole 2 penetrating the upper and lower surfaces (front and back surfaces) 211a and 211b of the upper surface plate 211 of the polishing apparatus 201, a window member 3 inserted into the measurement hole 2, and And a fixing portion 4 that holds the window member 3 and is fixed to the upper surface 211a of the upper surface plate 211. Further, the plate thickness measuring window structure 1 of the workpiece includes a cover 5 that covers the window member 3 and the fixing portion 4 and is fixed to the upper surface 211 a of the upper surface plate 211.

  The diameter of the measurement hole 2 is formed from the lower surface 211b of the upper surface plate 211 toward the upper surface 211a. A bolt 6 with a hole is inserted into and fixed to the upper portion of the measurement hole 2. The holed bolt 6 is provided with an insertion hole 6a penetrating the upper and lower surfaces. A bush 7 is fitted on the outer periphery of the bolt 6 with a hole, and is fixed to the upper surface 211 a of the upper surface plate 211. On the upper surface 7a of the bush 7, a plurality of fixing holes 7c are provided around a central hole 7b through which the bolt 6 with a hole is passed. The plurality of fixing holes 7 c are arranged at a predetermined interval in the circumferential direction of the bush 7. In addition, you may fix the fixing | fixed part 4 holding the window member 3 to the upper surface 211a of the upper surface plate 211 without going through the bolt 6 with a hole and the bush 7. FIG.

  Next, the configuration of the window member 3 will be described. The window member 3 includes a cylindrical portion 31 inserted into the measurement hole 2 and a window plate 32 provided at the lower end of the cylindrical portion 31. Furthermore, a covering material 33 that covers the outer peripheral surface 31 a of the cylindrical portion 31 is provided.

  The cylindrical portion 31 is formed in a cylindrical shape from a glass-based material such as quartz glass or BK-7, a material such as sapphire, or resin. One end of the cylindrical portion 31 is opened. In the cylindrical portion 31, a portion 31 b from the middle portion to the lower portion is inserted into the measurement hole 2. The upper edge portion 31d of the cylindrical portion 31 is bent outward and formed in a bowl shape.

The window plate 32 is formed in a plate shape from a glass-based material such as quartz glass or BK-7, or a translucent material such as sapphire or resin. The window plate 32 is provided at the lower end of the cylindrical portion 31 by welding, bonding, integral molding, or the like. Moreover, it is preferable that the cylindrical part 31 and the window board 32 are formed with the brittle material which has translucency from a viewpoint of generation | occurrence | production of the damage | wound by an abrasive | polishing agent, grinding | polishing residue, etc. In the case where the brittle material is selected as the material of the cylindrical portion 31 and the window plate 32, the window plate 32 is preferably provided by welding to the tubular portion 31. The covering material 33 is composed of a heat shrinkable tube made of resin. The covering material 33 is formed on the outer peripheral surface 3 of the cylindrical portion 31.
It is closely attached to 1a.

  Next, the configuration of the fixing unit 4 will be described. The fixing portion 4 includes an insertion portion 41 through which the upper portion 31 c of the cylindrical portion 31 is inserted, and a fixing portion main body 42 that is fitted on the outer periphery of the insertion portion 41 and is fixed to the upper surface 211 a of the upper surface plate 211.

  The insertion portion 41 includes a sleeve 411, an annular elastic member 412 fitted in a lower portion of the outer peripheral surface 411 e of the sleeve 411, and a collar 413 fitted in an intermediate portion of the outer peripheral surface 411 e of the sleeve 411. Further, the insertion portion 41 includes an annular elastic member 414 fitted into the upper portion of the outer peripheral surface 411e of the sleeve 411.

  The sleeve 411 is formed in a substantially cylindrical shape with resin. Inside the sleeve 411, the upper portion 31 c of the cylindrical portion 31 is passed through the covering material 33. An upper edge portion 31 d of the cylindrical portion 31 is locked to the upper surface 411 a of the sleeve 411 via a covering material 33.

  FIG. 3 is a plan view of the sleeve 411. FIG. 4 is a front view of the sleeve 411. The sleeve 411 includes a sleeve main body 4111 and a flange portion 4112 integrally formed on the outer periphery of the lower portion of the sleeve main body 4111. The sleeve body 4111 is formed in a cylindrical shape. The collar portion 4112 is formed in an annular shape.

  On the upper surface 411a of the sleeve 411 (the upper surface of the sleeve main body 4111), a plurality of upper notches 411b are provided facing downward. The plurality of upper cutouts 411 b are arranged at a predetermined interval in the circumferential direction of the sleeve 411. On the lower surface 411c of the sleeve 411 (the lower surfaces of the sleeve main body 4111 and the flange portion 4112), a plurality of lower notches 411d are provided facing upward. The plurality of lower notches 411d are arranged in the circumferential direction of the sleeve 411 and between adjacent upper notches 411b and 411b.

  As shown in FIG. 2, the annular elastic member 412 is formed of an elastic member such as a rubber material (for example, an O-ring) such as silicone. The annular elastic member 412 is supported by the flange portion 4112 of the sleeve 411 and is fitted into the lower portion of the outer peripheral surface 411 e of the sleeve main body 4111.

  FIG. 5 is a longitudinal sectional view of the collar 413. The collar 413 is formed in a cylindrical shape. The upper part 413b of the inner peripheral surface 413a of the collar 413 is formed so as to taper outward from the intermediate part 413c of the inner peripheral surface 413a. A lower portion 413d of the inner peripheral surface 413a of the collar 413 is formed so as to taper outward from the intermediate portion 413c of the inner peripheral surface 413a. As shown in FIG. 2, the collar 413 is fitted into an intermediate portion of the outer peripheral surface 411 e of the sleeve main body 4111 with the lower portion 413 d of the inner peripheral surface 413 a against the annular elastic member 412.

  As shown in FIG. 2, the annular elastic member 414 is formed of a member having elasticity such as a rubber material (for example, O-ring) such as silicone. The annular elastic member 414 is fitted into the upper portion of the outer peripheral surface 411e of the sleeve body 4111 so as to contact the upper portion 413b of the inner peripheral surface 413a of the collar 413.

  The fixed portion main body 42 includes a housing 421 and a cap 422 attached to the upper surface 421a of the housing 421.

  The housing 421 is formed in a cylindrical container shape. The housing 421 is supported by the bush 7. The lower surface 421b of the housing 421 is provided with a fitting hole 421c penetrating upward at a position facing the central hole 7b of the bush 7. The upper part of the bolt 6 with the hole passed through the central hole 7b of the bush 7 is fitted into the fitting hole 421c.

  An insertion portion 41 is accommodated in the housing 421. The housing 421 includes an annular elastic member 414, a collar 413, and an annular elastic member 412 of the insertion portion 41 that are pressed by the cap 422, and the outer peripheral side (fixed portion) of the annular elastic member 414 and the annular elastic member 412. By restricting deformation to the main body 42 side) and causing only deformation to the inner peripheral side (sleeve 411 side) of the annular elastic member 414 and the annular elastic member 412, the sleeve 411 is placed inside (window member 3 side). The sleeve 411 is tightened by being brought into surface contact with the outer peripheral surface 31a of the upper portion 31c of the cylindrical portion 31 through the covering material 33 so that pressure is evenly applied.

  FIG. 6 is a plan view of the housing 421. 7 is an AA cross-sectional view and a BB cross-sectional view of FIG. In the circumferential direction of the upper surface 421a of the housing 421, a plurality of housing fixing holes 421d are provided at positions corresponding to the plurality of fixing holes 7c (see FIG. 2) of the bush 7. The plurality of housing fixing holes 421d are formed from the upper surface 421a to the lower surface 421b of the housing 421.

  As shown in FIG. 2, housing fixing screws 423 are passed through the housing fixing holes 421 d and screwed into the fixing holes 7 c of the bush 7 through the housing fixing holes 421 d and the fixing holes 7 c of the bush 7. Accordingly, the housing 421 is fixed to the upper surface 211 a of the upper surface plate 211 via the bush 7.

  As shown in FIGS. 6 and 7, a plurality of housing adjustment holes 421e are provided on the upper surface 421a of the housing 421 on one side in the circumferential direction of the housing fixing hole 421d. The plurality of housing adjustment holes 421e are formed from the upper surface 421a to the lower surface 421b of the housing 421.

  As shown in FIG. 2, a housing adjustment screw 424 is inserted into and screwed into each housing adjustment hole 421e. The lower end of the housing adjusting screw 424 is in contact with the upper surface 7 a of the bush 7. A screw hole 424 a is provided on the upper surface of the housing adjusting screw 424. The mounting angle of the housing 421 is adjusted by adjusting the screwing amount of the housing adjusting screw 424 by turning the screw hole 424a.

  Further, a plurality of cap fixing holes 421f are provided on the upper surface 421a of the housing 421 on the other side in the circumferential direction of the housing fixing holes 421d. The plurality of cap fixing holes 421f are formed from the upper surface 421a to the lower surface 421b of the housing 421.

  FIG. 8 is a plan view of the cap 422. 9 is a cross-sectional view taken along the line CC and the line DD in FIG. 8. The cap 422 is formed in an annular shape. An insertion hole 422c is provided in the central portion of the upper surface 422a of the cap 422. The insertion hole 422c passes from the upper surface 422a to the lower surface 422b of the cap 422. As shown in FIG. 2, the sleeve 411 of the insertion portion 41 is passed through the insertion hole 422c.

  On the lower surface 422b of the cap 422, an annular fitting portion 4221 is provided around the insertion hole 422c. As shown in FIG. 2, the fitting portion 4221 is fitted between the upper end portion of the housing 421 and the upper end portion of the sleeve 411.

  As shown in FIGS. 8 and 9, a plurality of housing fixing through holes 422d are provided around the insertion holes 422c on the upper surface 422a of the cap 422 at positions corresponding to the housing fixing holes 421d (see FIG. 6). . Each housing fixing through hole 422d is formed through the upper surface 422a to the lower surface 422b of the cap 422 so that the housing fixing screw 423 (see FIG. 2) passes therethrough.

  On the upper surface 422a of the cap 422, an adjustment through hole 422e is provided around the insertion hole 422c at a position corresponding to the housing adjustment hole 421e (see FIG. 6). Each adjustment through hole 422e is formed through the upper surface 422a to the lower surface 422b of the cap 422 so that the housing adjustment screw 424 (see FIG. 2) passes therethrough.

  A plurality of cap fixing through holes 422f are provided around the insertion holes 422c on the upper surface 422a of the cap 422 at positions corresponding to the plurality of cap fixing holes 421f (see FIG. 6). The plurality of cap fixing through holes 422f are formed to penetrate from the upper surface 422a to the lower surface 422b of the cap 422. 2, cap fixing screws 425 are passed through the cap fixing through holes 422f and screwed into the cap fixing holes 421f through the cap fixing through holes 422f and the cap fixing holes 421f, respectively. Thus, the cap 422 is attached to the upper surface 421a of the housing 421, and the pressing force of the cap 422 against the annular elastic member 414 and the annular elastic member 412 is adjusted by adjusting the screwing amount of the cap fixing screw 425. is doing. As the cap fixing screw 425 is turned in the tightening direction, the pressing force of the cap 422 on the annular elastic member 414 and the annular elastic member 412 increases, and the deformation amount of the annular elastic member 414 and the annular elastic member 412 increases. . Since the annular elastic member 414 and the annular elastic member 412 are in contact with the cap 422, the housing 421, and the collar 413, the annular elastic member 414 and the annular elastic member 412 cannot be deformed in these directions, and the direction of the sleeve 411 Deforms only to As the deformation amount of the annular elastic member 414 and the annular elastic member 412 is increased, the amount (deformation amount) of the annular elastic member 414 and the annular elastic member 412 protruding toward the sleeve 411 increases. The amount of contraction toward the inside (window member 3 side) increases. Therefore, by adjusting the screwing amount of the cap fixing screw 425, the contraction amount in the inner side (window member 3 side) direction of the sleeve 411 can be adjusted, and the outer peripheral surface 31a of the upper portion 31c of the cylindrical portion 31 is adjusted. It is possible to make the surface contact so that the pressure is evenly applied and tighten with an appropriate force. In addition to the above, the optimal deformation amount of the annular elastic member 414 and the annular elastic member 412 is when the screwing amount of the cap fixing screw 425 is maximized, that is, when the cap fixing screw 425 is closed. You may adjust so that it may become.

  FIG. 10 is a plan view of the cover 5. FIG. 11 is a schematic perspective view of the cover 5 as viewed from the outer peripheral side of the upper surface plate 211. FIG. 12 is a schematic bottom view of the cover 5. The structure of the cover 5 will be described with reference to FIGS. 2 and 10 to 12. As shown in FIG. 2, the cover 5 includes a cover main body 51, a translucent plate 52 disposed on the upper surface 512 b of the cover main body 51, and an attachment portion 53 for attaching the translucent plate 52 to the upper surface 512 b of the cover main body 51. Prepare.

  The cover main body 51 is fixed to the upper surface 211 a of the upper surface plate 211 so as to cover the window member 3, the fixing portion 4, and the bush 7. The cover body 51 is formed in a cylindrical shape (see FIG. 11) from a transparent resin. The cover body 51 includes a peripheral wall 511, an upper collar 512 coupled to the upper end of the peripheral wall 511, and a bottom wall 513 coupled to the lower end of the peripheral wall 511.

  The peripheral wall 511 is formed so as to surround the outer periphery of the window member 3 and the fixed portion 4. The upper end of the peripheral wall 511 is notched obliquely downward from the inner peripheral side of the upper surface plate 211 toward the outer peripheral side (from the right side to the left side in FIG. 2).

  The upper collar 512 is provided so as to be obliquely lowered from the inner peripheral side of the upper surface plate 211 toward the outer peripheral side. The upper collar 512 is formed in an annular shape (see FIGS. 10 and 11) so as to cover the fixing portion 4. A transmission hole 512 a is provided in a portion of the upper collar 512 that faces the opening 31 e at the upper end of the cylindrical portion 31. Further, a plurality of mounting holes 512d are provided on the upper surface 512b of the upper collar 512.

  The bottom wall 513 is formed in an annular shape (see FIG. 12) so as to surround the outer periphery of the bush 7. The bottom wall 513 is disposed on the upper surface 211 a of the upper surface plate 211. A plurality of cover fixing holes 513 a are provided through the side surface of the bottom wall 513. A cover fixing screw 515 is passed through and screwed into each cover fixing hole 513a. The tip of each cover fixing screw 515 presses the peripheral surface of the bush 7. Thus, the cover 5 is fixed to the upper surface 211 a of the upper surface plate 211 via the bush 7. As shown in FIGS. 11 and 12, a plurality of notches 513 b are provided in the circumferential direction of the bottom wall 513 from the lower end of the bottom wall 513 to the lower part of the peripheral wall 511.

  As shown in FIGS. 2 and 10, the translucent plate 52 is disposed so as to block the transmission hole 512a. The translucent plate 52 is formed in a plate shape from a glass-based material such as quartz glass or BK-7, or a translucent material such as sapphire or resin.

  As shown in FIGS. 2, 10, and 11, the attachment portion 53 includes a pressing plate 531 that presses the translucent plate 52 against the upper surface 512 b of the upper collar 512 of the cover body 51, and the upper surface of the upper collar 512. And a plurality of screws 532 attached to 512b.

  The holding plate 531 is formed in a C-shaped plate that opens to the outer peripheral side of the upper surface plate 211. As a result, the pressing plate 531 is provided so as to surround the outer peripheral portion of the translucent plate 52 and constitutes the surrounding portion of the present embodiment. Since the pressing plate 531 is formed in a C-shaped plate that opens to the outer peripheral side of the upper surface plate 211, a notch 531 c that communicates the inside and the outside of the pressing plate 531 is formed on the outer peripheral side of the pressing plate 531. (Communication part) is provided. A plurality of mounting holes 531b are provided on the upper surface 531a of the pressing plate 531 at positions corresponding to the plurality of mounting holes 512d of the upper collar 512 of the cover body 51. The plurality of screws 532 are threaded through the plurality of mounting holes 531 b of the pressing plate 531 and the mounting holes 512 d of the upper collar 512.

  Next, a method for measuring the thickness of the workpiece W using the workpiece thickness measuring window structure 1 will be described with reference to FIG. When the window member 3 is irradiated with infrared rays Ra from the laser head 312 (see FIG. 1) of the plate thickness measuring device 301 during the polishing of the workpiece W via the light transmitting plate 52 of the cover 5, the infrared rays Ra are emitted from the window member 3. The inside of the cylindrical portion 31 is irradiated from the opening 31 e at the upper end. The irradiated infrared ray Ra passes through the lower window plate 32 and is irradiated onto the front surface Wa of the workpiece W, and the reflected light Rb reflected by the front surface Wa and the rear surface Wb of the workpiece W passes through the window plate 32 and opens at the upper end. The light is received by the laser head 312 of the plate thickness measuring device 301 through the light transmitting plate 52 of the cover 5 through the part 31e.

  Next, effects of the plate thickness measuring window structure 1 of the workpiece according to the present embodiment will be listed and described.

(1) In the work thickness measurement window structure 1 of the present embodiment, the measurement hole 2 that penetrates the upper and lower surfaces 211a, 211b of the upper surface plate 211, and the lower end side (one end side) are inserted into the measurement hole 2. And a window member 3 having a translucent window plate 32 provided at one end of the cylindrical portion 31. Furthermore, the thickness measurement window structure 1 of the workpiece according to the present embodiment is held on the upper surface 211a of the upper surface plate 211 while holding the outer peripheral surface 31a on the upper end side (the other end side) of the cylindrical portion 31 in surface contact. A fixed portion 4 is provided. That is, in the work thickness measurement window structure 1 of the present embodiment, the fixed portion 4 holds the outer peripheral surface 31a on the other end side of the cylindrical portion 31 so as to be in surface contact. As a result, the fixed portion 4 has a wider range of holding the cylindrical portion 31 of the window member 3 than in the prior art, and therefore continues to hold the cylindrical portion 31 of the window member 3 while maintaining a pre-adjusted angle. Is possible. Therefore, the plate thickness measurement window structure 1 of the workpiece according to the present embodiment can stably fix the window member 3 to the upper surface 211 a of the upper surface plate 211. Furthermore, the window member 3 is stably fixed to the upper surface 211a of the upper surface plate 211, so that it is possible to prevent the window member 3 from being inclined unexpectedly due to vibration of the upper surface plate 211 or the like. As a result, the window member 3 can reliably transmit the amount of infrared rays Ra and reflected light Rb necessary for the measurement of the plate thickness Wt of the workpiece W, so that a reduction in measurement accuracy of the plate thickness Wt can be suppressed.

(2) In the workpiece thickness measurement window structure 1 according to the present embodiment, the fixed portion 4 includes the sleeve 411 through which the upper end side of the cylindrical portion 31 is passed, and the annular shape fitted into the outer peripheral surface 411 e of the sleeve 411. The elastic members 414 and 412 are provided. Furthermore, the fixing portion 4 includes a fixing portion main body 42 that is fixed to the upper surface 211a of the upper surface plate 211 by restraining the outer periphery of the annular elastic member. The fixing portion main body 42 presses the outer periphery of the annular elastic member to bring the sleeve 411 into surface contact with the outer peripheral surface 31a on the upper end side of the cylindrical portion 31 so that pressure is evenly applied, and tightens the outer peripheral surface 31a. The upper surface plate 211 is fixed so as to be in contact with the upper surface 211 a. As a result, the fixing portion 4 has a wider range for holding the cylindrical portion 31 of the window member 3, so that the cylindrical portion 31 of the window member 3 can be continuously held while maintaining a pre-adjusted angle. . Therefore, the plate thickness measurement window structure 1 of the workpiece according to the present embodiment can stably fix the window member 3 to the upper surface 211 a of the upper surface plate 211. In particular, when the cylindrical portion 31 uses quartz glass, a glass-based material such as BK-7, or a brittle material such as sapphire, the outer peripheral surface 31 a on the upper end side of the cylindrical portion 31 is dispersed by the sleeve 411. However, it is possible to maintain the surface contact so that no local pressure is applied. Therefore, the plate thickness measuring window structure 1 of the workpiece according to the present embodiment can stably fix the window member 3 to the upper surface 211a of the upper surface plate 211 while preventing the window member 3 from being damaged.

(3) In the workpiece thickness measurement window structure 1 of the present embodiment, a plurality of cutouts (upper cutout 411b and lower cutout 411d) are provided at predetermined intervals in the circumferential direction on both ends of the sleeve 411, respectively. Is provided. For this reason, the sleeve 411 is easily contracted as a whole as compared with the case where there is no cutout, and the contact area with the outer peripheral surface 31 a on the upper end side of the cylindrical portion 31 is increased. Thereby, the fixing | fixed part 4 becomes possible [holding the outer peripheral surface 31a of the upper end side of the cylindrical part 31 so that a local pressure may not be applied, disperse | distributing pressing pressure further. Therefore, the plate thickness measuring window structure 1 of the workpiece according to the present embodiment can stably fix the window member 3 to the upper surface 211a of the upper surface plate 211 while further preventing the window member 3 from being damaged.

(4) In the plate thickness measurement window structure 1 of the workpiece according to the present embodiment, the cylindrical portion 31 and the window plate 32 are formed of a brittle material having translucency. Thereby, the cylindrical part 31 and the window plate 32 can suppress the generation | occurrence | production of the damage | wound by an abrasive | polishing agent, grinding | polishing residue, etc. which becomes a factor which obstructs transmission of infrared rays Ra or reflected light Rb. Further, since the window plate 32 is provided by being welded to one end of the cylindrical portion 31, it is less likely to be peeled than when the window plate 32 is provided by being bonded to one end of the cylindrical portion 31. Therefore, the workpiece thickness measuring window structure 1 of the present embodiment increases the durability of the window member 3 and stably fixes the workpiece W while fixing the window member 3 to the upper surface 211a of the upper surface plate 211. It can be measured reliably.

(5) The workpiece thickness measurement window structure 1 according to the present embodiment includes a cover 5 that covers the window member 3 and the fixing portion 4 and is fixed to the upper surface 211 a of the upper surface plate 211. The cover 5 is provided with a translucent plate 52, which is a translucent part having translucency, at a portion facing the opening 31 e at the upper end of the cylindrical part 31. As a result, infrared rays Ra are transmitted through the translucent plate 52 into the cylindrical portion 31, and the cover 5 can prevent the abrasive, cleaning water, dust, and the like from entering the cylindrical portion 31. Become. Therefore, the plate | board thickness measuring window structure 1 of the workpiece | work of this Embodiment can improve waterproofness and dustproofness.

(6) In the workpiece thickness measuring window structure 1 of the present embodiment, the light transmitting plate 52 of the cover 5 is from the inner peripheral side of the upper surface plate 211 to the outer peripheral side with respect to the upper surface 211a of the upper surface plate 211. It is placed diagonally down. As a result, even if abrasives, cleaning water, dust or the like is applied to the light transmitting plate 52 during polishing of the workpiece W, the polishing plate, cleaning water, dust or the like is transmitted using the rotation of the upper surface plate 211. It becomes possible to remove efficiently from the surface of 52. Therefore, the plate | board thickness measurement window structure 1 of the workpiece | work of this Embodiment can further improve waterproofness and dustproofness. Further, since the translucent plate 52 is disposed obliquely with respect to the upper surface 211 a of the upper surface plate 211, reflection from the translucent plate 52 when the infrared ray Ra is irradiated from the laser head 312 to the translucent plate 52. Light can be reflected in a direction different from the installation direction of the laser head 312. Thereby, the laser head 312 can prevent receiving reflected light different from the reflected light Rb from the workpiece W, and can prevent the measurement accuracy of the plate thickness Wt from being lowered.

(7) In the workpiece thickness measurement window structure 1 of the present embodiment, a pressing plate 531 (a surrounding portion) surrounding the outer peripheral portion of the light transmitting plate 52 is provided around the light transmitting plate 52 of the cover 5. . Further, on the outer peripheral side of the upper platen 211 of the presser plate 531, a notch 531c (communication portion) that connects the inside and the outside of the presser plate 531 is provided. As a result, even if abrasives, cleaning water, dust, or the like is applied to the light transmitting plate 52, the upper surface plate 211 is cut through the notch 531c using the rotation of the upper surface plate 211. It becomes possible to remove efficiently from the surface of the translucent plate 52 on the outer peripheral side of 211. Therefore, the plate | board thickness measurement window structure 1 of the workpiece | work of this Embodiment can further improve waterproofness and dustproofness.

  Further, the upper edge portion 31 d of the cylindrical portion 31 is held by the fixing portion 4 while being locked to the upper surface 411 a of the sleeve 411 of the fixing portion 4. As a result, the window member 3 can be prevented from falling off the fixed portion 4. Therefore, the plate thickness measuring window structure 1 of the workpiece according to the present embodiment can stably fix the window member 3 by the upper surface 211 a of the upper surface plate 211. Further, the upper edge portion 31 d of the cylindrical portion 31 is formed in a hook shape and is locked to the upper surface 411 a of the sleeve 411 of the fixing portion 4. Thereby, the window member 3 can be prevented from falling off with a simple configuration. Therefore, the plate thickness measurement window structure 1 of the workpiece according to the present embodiment can stably fix the window member 3 to the upper surface 211a of the upper surface plate 211 while suppressing the manufacturing cost.

  Further, the window plate 32 is formed of a material having translucency. In particular, when a brittle material is used for the cylindrical portion 31 and the window plate 32, the heat resistance can be increased. In addition, when the window plate 32 is formed of a fragile material having translucency, it is possible to suppress the scratches that hinder the transmission of the infrared rays Ra and the reflected light Rb. The amount of infrared rays Ra and reflected light Rb necessary for the measurement of can be transmitted more reliably. Accordingly, a decrease in the accuracy of the measured value of the plate thickness Wt can be further suppressed.

  Further, the window member 3 includes a resin covering material 33 that covers the outer peripheral surface 31 a of the cylindrical portion 31. Thereby, the cylindrical member 31 is protected by the covering material 33 and the strength of the window member 3 is improved. Further, even if the cylindrical portion 31 is damaged, the covering material 33 can prevent the fragments from scattering. Further, since the fixing portion 4 holds the outer peripheral surface 31 a of the cylindrical portion 31 via the covering material 33, the outer peripheral surface 31 a of the cylindrical portion 31 can be reliably secured using the elasticity and the friction coefficient of the covering material 33. It becomes possible to hold on. Therefore, the plate thickness measuring window structure 1 of the workpiece according to the present embodiment can stably fix the window member 3 by the upper surface 211 a of the upper surface plate 211.

  Further, since the collar 413 is fitted between the annular elastic member 414 and the annular elastic member 412, the positions of the annular elastic member 414 and the annular elastic member 412 are fixed to the sleeve 411. As a result, the sleeve 411 is tightened by the annular elastic member 414 and the annular elastic member 412 so that pressure is evenly applied to the outer peripheral surface 31 a on the upper end side of the cylindrical portion 31. Therefore, the fixed portion 4 can hold the outer peripheral surface 31a on the upper end side of the cylindrical portion 31 so that local pressure is not applied while the pressing pressure is reliably dispersed. Therefore, the plate thickness measuring window structure 1 of the workpiece according to the present embodiment can stably fix the window member 3 to the upper surface 211a of the upper surface plate 211 while further preventing the window member 3 from being damaged.

  Further, the upper portion 413b of the inner peripheral surface 413a of the collar 413 is formed so as to be tapered outward from the intermediate portion 413c of the inner peripheral surface 413a, and supports the annular elastic member 414. For this reason, the position of the annular elastic member 414 is securely fixed. Further, the lower portion 413d of the inner peripheral surface 413a of the collar 413 is formed so as to be tapered outward from the intermediate portion 413c of the inner peripheral surface 413a and is in contact with the annular elastic member 412. For this reason, the position of the annular elastic member 412 is securely fixed. Further, since the upper part 413b and the lower part 413d of the inner peripheral surface 413a of the collar 413 are formed so as to taper outward from the intermediate part 413c, when the annular elastic members 414 and 412 are pressed by the cap 422, the sleeve It is deformed so as to protrude reliably only in the direction of 411. As a result, the sleeve 411 is tightened by the annular elastic member 414 and the annular elastic member 412 so that pressure is more evenly applied to the outer peripheral surface 31 a on the upper end side of the cylindrical portion 31. Accordingly, the fixing portion 4 can hold the outer peripheral surface 31a on the upper end side of the cylindrical portion 31 more securely so as not to apply a local pressure while dispersing the pressing pressure. Therefore, the plate thickness measuring window structure 1 of the workpiece according to the present embodiment can stably fix the window member 3 to the upper surface 211a of the upper surface plate 211 while further preventing the window member 3 from being damaged.

  The fixing portion 4 includes a housing 421 in which the fixing portion main body 42 accommodates the insertion portion 41, and a cap 422 attached to the upper surface 421 a of the housing 421. As a result, the fixing portion 4 can prevent the abrasive, cleaning water, dust and the like from entering the housing 421 with the cap 422. Therefore, the plate | board thickness measurement window structure 1 of the workpiece | work of this Embodiment can further improve waterproofness and dustproofness.

  The translucent plate 52 is made of a translucent material. In particular, when a brittle material is used for the light-transmitting plate 52, it is possible to suppress the occurrence of scratches caused by abrasives, polishing debris, etc., which are factors that hinder the transmission of infrared rays Ra and reflected light Rb. Therefore, the plate thickness measurement window structure 1 of the workpiece according to the present embodiment can increase the durability of the translucent plate 52. Further, since the translucent plate 52 can suppress the scratches from being reduced, a decrease in translucency can be suppressed. Therefore, it is possible to reliably transmit the infrared rays Ra and the reflected light Rb in amounts necessary for measuring the plate thickness Wt of the workpiece W. It becomes possible. Accordingly, a decrease in the accuracy of the measured value of the plate thickness Wt can be further suppressed. Further, the light-transmitting plate 52 can be improved in heat resistance by being formed of a light-transmitting brittle material.

  Further, a notch 513 b is provided from the lower end of the bottom wall 513 of the cover body 51 to the lower portion of the peripheral wall 511. Thus, even if abrasives, cleaning water, dust or the like enters the cover body 51 during polishing of the workpiece W, the polishing agent, cleaning water, dust or the like is removed from the notch 513b using the rotation of the upper surface plate 211. It becomes possible to discharge to the outside of the cover body 51. Therefore, the plate | board thickness measurement window structure 1 of the workpiece | work of this Embodiment can further improve waterproofness and dustproofness.

  The embodiment of the present invention has been described in detail above with reference to the drawings. However, the specific configuration is not limited to this embodiment, and design changes that do not depart from the gist of the present invention are not limited to this embodiment. Included in the invention.

  For example, in the present embodiment, the workpiece thickness measuring window structure 1 is installed on the upper surface 211a of the upper surface plate 211, but may be installed on the lower surface 212b which is the surface of the lower surface plate 212.

  In the present embodiment, the translucent plate 52 is formed of a brittle material having translucency, but the material forming the translucent plate 52 is not limited to the brittle material having translucency. Even when the material forming the light-transmitting plate 52 is a resin, the same effect as the present embodiment can be obtained. Further, in the work thickness measurement window structure 1 of the present embodiment, the present invention is applied to the polishing apparatus 201 that polishes both surfaces of the work W, but may be applied to a polishing apparatus that polishes one surface of the work W.

  Moreover, although the cover 5 of this Embodiment was applied to the window member 3 and the fixing | fixed part 4 which concern on this invention, you may apply to the window member and fixing | fixed part other than this invention. In this case, the workpiece thickness measurement window structure includes a measurement hole penetrating the front and back surfaces of a surface plate of a polishing apparatus for polishing a thin plate-shaped workpiece, a cylindrical portion having one end inserted into the measurement hole, and the cylinder. And a window member having a translucent window plate provided at one end of the shape portion. Further, the thickness measurement window structure of the workpiece in this case includes a fixed portion that holds the cylindrical portion and is fixed to the surface of the surface plate, and covers the cylindrical portion and the fixed portion. A cover fixed to the surface is provided. Further, the cover is provided with a translucent portion having translucency at a portion facing the opening at the other end of the cylindrical portion. In the conventional thickness measurement window structure for a workpiece, since the cylindrical portion is exposed, there is a problem that abrasives, cleaning water, dust and the like enter the cylindrical portion. However, in the work thickness measurement window structure in this case, the cover can prevent the abrasive, cleaning water, dust and the like from entering the cylindrical portion, so that the waterproofness and dustproofness can be improved. .

  In addition, the insertion portion 41 of the present embodiment is configured by the annular elastic members 412 and 414 and the collar 413. However, a plurality of collars are provided, and an annular elastic member is provided between the plurality of collars. Thus, it is possible to provide more contact points for shrinking the sleeve 411 inward (window member 3 side) by the annular elastic member. In that case, it becomes possible to apply the pressing force from the annular elastic member to the sleeve 411 while evenly distributing the pressing force, and the outer peripheral surface 31a on the upper end side of the cylindrical portion 31 can be locally distributed while more reliably distributing the pressing pressure. It is possible to keep the pressure from being applied. In the present embodiment, a plurality of annular elastic members are used. However, even if a single elastic member is used, the same effects as those of the present invention can be obtained.

DESCRIPTION OF SYMBOLS 1 Window thickness measurement window structure 2 Measurement hole 3 Window member 4 Fixing part 5 Cover 31 Cylindrical part 31a Outer peripheral surface 31e Opening part 32 Window board 42 Fixing part main body 52 Translucent board (translucent part)
201 Polishing device 211 Upper surface plate (surface plate)
211a Upper surface (surface)
211b Bottom (back)
411 Sleeve 411b Upper notch 411d Lower notch 412 Annular elastic member 414 Annular elastic member 531 Holding plate (enclosure)
531c Notch (communication part)

Claims (7)

A measurement hole penetrating the front and back surfaces of a surface plate of a polishing apparatus for polishing a thin plate workpiece,
A window member having a cylindrical portion in which one end side is inserted into the measurement hole and a translucent window plate provided at one end of the cylindrical portion;
A fixed portion that is fixed to the surface of the surface plate by holding the outer peripheral surface of the other end side of the cylindrical portion in surface contact;
Equipped with a,
The fixing portion includes a sleeve through which the other end side of the cylindrical portion is passed, an annular elastic member fitted on the outer peripheral surface of the sleeve, and a surface of the surface plate by restraining an outer periphery of the annular elastic member A window structure for measuring a plate thickness of a workpiece, comprising: a fixed portion main body fixed to the workpiece. In the thickness measurement window structure of the workpiece according to claim 1 ,
A thickness measurement window structure for a workpiece, wherein a plurality of notches are provided at predetermined intervals in the circumferential direction on both ends of the sleeve. A measurement hole penetrating the front and back surfaces of a surface plate of a polishing apparatus for polishing a thin plate workpiece,
A window member having a cylindrical portion in which one end side is inserted into the measurement hole and a translucent window plate provided at one end of the cylindrical portion;
A fixed portion that is fixed to the surface of the surface plate by holding the outer peripheral surface of the other end side of the cylindrical portion in surface contact;
With
A plate thickness measuring window structure for a workpiece, wherein the cylindrical portion and the window plate are formed of a brittle material having translucency. In the plate | board thickness measurement window structure of the workpiece | work of Claim 1 or Claim 2 ,
A plate thickness measuring window structure for a workpiece, wherein the cylindrical portion and the window plate are formed of a brittle material having translucency. In the window thickness measurement window structure of the workpiece according to any one of claims 1 to 4,
A cover that covers the window member and the fixing portion and is fixed to the surface of the surface plate, the cover having a light-transmitting property at a portion facing the opening at the other end of the cylindrical portion. A window structure for measuring a plate thickness of a workpiece, characterized in that a part is provided. In the window thickness measurement window structure of the workpiece according to claim 5,
The work thickness measurement window structure according to claim 1, wherein the translucent portion is disposed so as to be obliquely lowered from the inner peripheral side to the outer peripheral side of the surface plate with respect to the surface of the surface plate. In the plate | board thickness measurement window structure of the workpiece | work of Claim 5 or Claim 6,
An encircling portion surrounding the translucent portion is provided around the translucent portion, and a communication portion that communicates the inside and the outside of the encircling portion is provided on the outer peripheral side of the surface plate of the encircling portion. A window structure for measuring the thickness of workpieces.