Processing apparatus and method of inspecting holding surface

Abstract

To confirm a state of a holding surface in a state of sucking and holding a plate-like object.SOLUTION: The processing apparatus 1 includes a holding table 6 having a holding surface 61 that suction-holds a workpiece 200 having a back surface 201 and a front surface in a state in which the back surface 201 is exposed, a grinding unit that performs grinding processing that is predetermined processing on the workpiece 200 held by the holding table 6, and a control unit that controls the holding table 6 and the grinding unit in a state in which the workpiece 200 is suction-held on the holding surface 61. The workpiece holding apparatus includes the thickness measuring unit 80 that measures the thickness of the workpiece 200 in the plurality of regions, the height measuring unit 90 that measures the height of the workpiece 200 in the plurality of regions in the state in which the workpiece 200 is sucked and held by the holding surface 61, and the controller, and the controller has the calculating section that calculates the shape of the holding surface 61 of the holding table 6 on the basis of the thicknesses of the workpiece 200 in the plurality of regions measured by the thickness measuring unit 80 and the heights of the workpiece 200 in the plurality of regions measured by the height measuring unit 90.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a processing device and a method for inspecting a holding surface. [Background technology]

[0002] A known processing device for grinding and thinning a plate-like object such as a semiconductor wafer is a grinding wheel with grinding stones arranged in a ring, which is attached to a spindle and rotated while being brought into contact with the plate-like object to grind it (see, for example, Patent Document 1).

[0003] The processing device shown in Patent Document 1 and other documents performs grinding processing while the plate-shaped object is held by suction on a holding table, so it has been pointed out that the shape of the holding surface may affect the shape of the plate-shaped object after grinding. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5841846 Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, in order to check the shape of the holding surface, methods being considered include attaching a dial gauge to the spindle that rotates the grinding wheel and moving it over the holding surface of the holding table to measure the height of the holding surface, and measuring the distance to the holding surface by projecting light onto the holding table and receiving the light reflected by the holding surface.

[0006] However, none of the above methods hold the plate-shaped object by suction, and therefore there is a problem in that it is not possible to accurately grasp the state of the holding surface when actually grinding the plate-shaped object.

[0007] The present invention has been made in view of the above circumstances, and aims to make it possible to check the state of the holding surface when a plate-like object is sucked and held. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems and achieve the object, the processing apparatus of the present invention comprises a holding table having a holding surface that adsorbs and holds a plate-like object having one side and another side opposite the one side with the one side exposed, a processing unit that performs a predetermined process on the plate-like object held on the holding table, a thickness measurement unit that measures the thickness of the plate-like object in multiple regions while the plate-like object is adsorbed and held on the holding surface, a height measurement unit that measures the height of the plate-like object in multiple regions while the plate-like object is adsorbed and held on the holding surface, and a controller, wherein the controller has a calculation unit that calculates the shape of the holding surface of the holding table that holds the plate-like object based on the thickness of the plate-like object in the multiple regions measured by the thickness measurement unit and the height of the plate-like object in the multiple regions measured by the height measurement unit.

[0009] In the processing device, the thickness measurement unit may measure the thickness of the plate-like object, and the height measurement unit may measure the height of the plate-like object simultaneously.

[0010] In the processing apparatus, a plurality of thickness measuring units and a plurality of height measuring units may be provided.

[0011] In the processing device, the thickness measurement unit may be a non-contact thickness measurement unit including a light-projecting section that projects measurement light onto the plate-like object, a spectroscopic section that separates the interference light between the reflected light reflected from one surface of the plate-like object and the reflected light reflected from the other surface opposite to the one surface, and a light-receiving section that receives the interference light separated by the spectroscopic section.

[0012] In the processing device, the height measurement unit may be a non-contact height measurement unit including a light-projecting unit that irradiates the plate-like object with measurement light having multiple wavelength bands, an optical element that generates chromatic aberration along the optical axis direction of the light emitted from the light-projecting unit and converges the light to irradiate the plate-like object, a spectroscopic unit that disperses the light irradiated to the plate-like object by the optical element and focused and reflected on one surface of the plate-like object, and a light-receiving unit that receives the light dispersed by the spectroscopic unit.

[0013] In the processing device, the height measurement unit may be a non-contact height measurement unit including a light-projecting section that projects measurement light onto the plate-like object, a branching section that splits the light emitted from the light-projecting section into one light and another light, a spectroscopic section that splits the interference light between the reflected light of the one light branched by the branching section that is reflected by one surface of the plate-like object and the reflected light of the other light branched by the branching section that is reflected by a reference mirror, and a light-receiving section that receives the interference light split by the spectroscopic section.

[0014] The holding surface inspection method of the present invention is characterized by comprising an adsorption holding step of adsorbing and holding a plate-like object on the holding surface of a holding table, a thickness measurement step of measuring the thickness of the plate-like object held on the holding surface in multiple regions, a height measurement step of measuring the height of the plate-like object held on the holding surface in multiple regions, and a calculation step of calculating the shape of the holding surface that holds the plate-like object based on the thickness of the plate-like object in the multiple regions measured in the thickness measurement step and the height of the plate-like object in the multiple regions measured in the height measurement step.

[0015] In the method for inspecting a holding surface, the thickness measuring step and the height measuring step may be performed simultaneously. [Effects of the Invention]

[0016] The present invention provides an advantage in that it is possible to check the state of the holding surface when a plate-like object is sucked and held. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view schematically illustrating an example of the configuration of a processing apparatus according to the first embodiment. [Figure 2] FIG. 2 is a perspective view schematically showing a plate-like object to be treated by the treatment device shown in FIG. [Figure 3] FIG. 3 is a plan view schematically showing a holding table and a measuring unit of the processing apparatus shown in FIG. [Figure 4] FIG. 4 is a side view, partially in section, schematically showing the holding table and the measuring unit shown in FIG. [Figure 5] FIG. 5 is a side view, partly in section, schematically showing the configuration of the thickness measurement unit of the measurement section shown in FIG. [Figure 6] FIG. 6 is a side view, partially in section, schematically showing the configuration of the height measurement unit of the measurement section shown in FIG. [Figure 7] FIG. 7 is a flowchart showing the flow of the method for inspecting the holding surface according to the first embodiment. [Figure 8] FIG. 8 is a side view, partially in section, schematically showing the configuration of a height measurement unit of a measurement section of a processing apparatus according to the second embodiment. [Figure 9] FIG. 9 is a side view, partially in section, schematically showing the configuration of a height measurement unit of a measurement section of a processing apparatus according to a modified example of the second embodiment. [Figure 10] FIG. 10 is a plan view schematically showing a holding table and a measuring unit of a processing apparatus according to the first embodiment and the first modification of the second embodiment. [Figure 11] FIG. 11 is a side view, partially in section, schematically showing the holding table and the measuring unit shown in FIG. [Figure 12] FIG. 12 is a plan view schematically showing a holding table and a measuring unit of a processing apparatus according to the first embodiment and the second modification of the second embodiment. [Figure 13] FIG. 13 is a side view, partially in section, schematically showing the holding table and the measuring unit shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0018] Modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the configuration can be made within the scope of the gist of the present invention.

[0019] [Embodiment 1] A processing apparatus according to a first embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a perspective view schematically showing an example of the configuration of the processing apparatus according to the first embodiment. Fig. 2 is a perspective view schematically showing a plate-like object to be processed by the processing apparatus shown in Fig. 1.

[0020] (plate-shaped object) The processing apparatus 1 shown in Fig. 1 according to the first embodiment is a grinding apparatus that performs grinding, which is a process, on a plate-like object 200 shown in Fig. 2. The plate-like object 200 to be processed by the processing apparatus 1 shown in Fig. 1 is a wafer such as a disk-shaped semiconductor wafer or an optical device wafer, whose substrate is made of silicon, sapphire, gallium, or the like.

[0021] 2, the plate-like object 200 has a flat back surface 201 (corresponding to one surface) and a flat front surface 202 (corresponding to the other surface) opposite the back surface 201. The plate-like object 200 has devices (not shown) formed in each region partitioned by planned division lines set in a grid pattern on the front surface 202.

[0022] The device is, for example, an integrated circuit such as an IC (Integrated Circuit) or an LSI (Large Scale Integration), an image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), a MEMS (Micro Electro Mechanical Systems), or a semiconductor memory (storage device).

[0023] In the first embodiment, the back surface 201 of the plate-like object 200 behind the front surface 202 is ground by the processing device 1 to thin the plate-like object 200 to a predetermined finishing thickness, and then the plate-like object 200 is divided into individual devices along the planned division lines. Note that in the present invention, the plate-like object 200 does not necessarily have devices formed on the front surface 202.

[0024] (Processing device) The processing device 1 according to the first embodiment is a grinding device that grinds the back surface 201 of a plate-like object 200 to thin the plate-like object 200 to a predetermined finishing thickness. As shown in Fig. 1, the processing device 1 includes an apparatus base 2, a turntable 5, a plurality of holding tables 6 (two in the first embodiment) installed on the turntable 5, a grinding unit 10, a grinding feed unit 30, a cassette mounting table 8, an alignment unit 40, a transport unit 50, a cleaning unit 60, a measurement unit 70, and a controller 100.

[0025] The turntable 5 is a disk-shaped table provided on the upper surface of the device base 2, and is rotatable about an axis parallel to the Z-axis direction in a horizontal plane, and is rotationally driven at a predetermined timing. The Z-axis direction is parallel to the vertical direction. On the turntable 5, for example, two holding tables 6 are arranged at equal intervals, for example, at a phase angle of 180 degrees. That is, the turntable 5 has a plurality of holding tables 6 arranged at equal angles (180 degrees in the first embodiment) in the circumferential direction.

[0026] The upper surfaces of these two holding tables 6 are made of a porous material such as porous ceramics, and serve as holding surfaces 61 that suction-hold the plate-like object 200. That is, the holding tables 6 have holding surfaces 61. The holding surfaces 61 of the holding tables 6 are connected to a suction source (not shown), and when the holding surfaces 61 are sucked by the suction source, the plate-like object 200 placed on the holding surfaces 61 is suction-held on the holding surfaces 61 with the back surfaces 201 exposed.

[0027] During grinding, the holding table 6 is rotated by a rotation mechanism around an axis parallel to the Z-axis direction. The holding table 6 is moved sequentially to the carry-in / out position 301, the grinding position 302, and the carry-in / out position 301 by the rotation of the turntable 5. That is, the turntable 5 rotates around its axis to position each holding table 6 at the grinding position 302. The rotation angle (direction) of the holding table 6 around its axis is detected by an angle detector. The angle detector outputs the detection result to the controller 100.

[0028] The loading / unloading position 301 is an area where the plate-shaped object 200 is loaded or unloaded onto the holding table 6, and the grinding position 302 is an area where the grinding unit 10 performs grinding (equivalent to processing) on ​​the plate-shaped object 200 held on the holding table 6.

[0029] The grinding unit 10 is disposed above the holding table 6 positioned at the grinding position 302, and is a processing unit that performs a predetermined process, namely grinding, on the plate-like object 200 held on the holding table 6. The grinding unit 10 is equipped with a grinding wheel 11 having annularly arranged grinding stones 112 that grind the back surface 201 of the plate-like object 200 held by the holding table 6, and grinds the back surface 201 of the plate-like object 200 held on the holding surface 61 of the holding table 6 at the grinding position 302.

[0030] The grinding unit 10 is supported by an upright column 3 erected from one end of the device base 2 in the Y-axis direction parallel to the horizontal direction via a grinding feed unit 30. The grinding unit 10 has a spindle (not shown) arranged extending along the Z-axis direction, a spindle motor 12 that rotates the spindle around its axis, a spindle housing 13 (corresponding to a housing) that supports the spindle rotatably around its axis, and a grinding wheel 11.

[0031] The spindle housing 13 is formed in a cylindrical shape and accommodates the spindle therein so as to be rotatable about its axis with the lower end of the spindle exposed.

[0032] The grinding wheel 11 is fixed to the lower end of the spindle. The grinding wheel 11 includes a wheel base 111 formed in an annular shape and fixed to the lower end of the spindle, and a plurality of grinding stones 112 arranged in an annular shape on the underside of the wheel base 111. The grinding stones 112 are arranged at equal intervals in the circumferential direction of the wheel base 111, and a plurality of grinding stones 112 are fixed to the underside of the wheel base 111.

[0033] The grinding wheel 112 is configured as a so-called segment grinding wheel formed into a single mass by mixing abrasive grains such as diamond or CBN (Cubic Boron Nitride) with a bonding material (also called a bond material) made of metal, ceramic, resin, or the like. The grinding wheel 112 grinds the back surface 201 of the plate-like object 200. In the first embodiment, the diameter of the circle formed by connecting the outer edges of the grinding wheel 112 is equal to the outer diameter of the plate-like object 200, but it does not have to be equal.

[0034] The grinding unit 10 grinds the back surface 201 of the plate-like object 200 by rotating the spindle and grinding wheel 11 around the axis using the spindle motor and supplying grinding water to the back surface 201 of the plate-like object 200 held on the holding table 6 at the grinding position 302, while the grinding feed unit 30 moves the grinding wheel 112 closer to the holding table 6 at a predetermined feed speed.

[0035] The grinding feed unit 30 moves the grinding units 10 in the Z-axis direction, bringing the grinding units 10 closer to and further away from the holding table 6. In the first embodiment, the grinding feed unit 30 is mounted on an upright column 3 that stands from one end of the device base 2 in the Y-axis direction, which is parallel to the horizontal direction. The grinding feed unit 30 includes a well-known ball screw that is rotatable about its axis, a well-known motor that rotates the ball screw about its axis, and a well-known guide rail that supports the spindle housing 13 of each grinding unit 10 so that it can move in the Z-axis direction.

[0036] In embodiment 1, the grinding unit 10 is arranged such that the axis which is the center of rotation of the grinding wheel 11 and the axis which is the center of rotation of the holding table 6 are parallel to each other with a horizontal gap between them, and the grinding wheel 112 passes over the center of the back surface 201 of the plate-like object 200 held on the holding table 6.

[0037] The cassette 7 is placed on the cassette placing table 8. The cassette 7 is a storage container having a plurality of slots for storing a plurality of plate-like objects 200. The cassette 7 stores a plurality of plate-like objects 200 before and after grinding. In embodiment 1, a pair of cassette placing tables 8 are provided, and a cassette 7 is placed on each of them. The cassette placing tables 8 support the cassette 7 so that it can be raised and lowered along the Z-axis direction. The alignment unit 40 is a table on which the plate-like object 200 removed from the cassette 7 is temporarily placed and its center is aligned.

[0038] The transport unit 50 transports the plate-like object 200. The transport unit 50 includes a carry-in unit 51, a carry-out unit 52, and a carry-in / out unit 53.

[0039] The carry-in unit 51 has a suction pad 511 at its tip end that adsorbs the plate-like object 200, and is formed in the shape of an arm that is provided on the apparatus base 2 so as to be able to swing freely around its base end. The carry-in unit 51 adsorbs and holds the unground plate-like object 200 that has been aligned by the alignment unit 40 onto the suction pad 511, and carries it onto the holding table 6 located at the carry-in / out position 301.

[0040] The carry-out unit 52 has a suction pad 521 at its tip end that adsorbs the plate-like object 200, and is formed in the shape of an arm that is provided on the apparatus base 2 so as to be able to swing freely around its base end. The carry-out unit 52 adsorbs and holds the ground plate-like object 200 on the holding table 6 located at the carry-in / out position 301 to the suction pad 521, and carries it out to the cleaning unit 60.

[0041] The carry-in / out unit 53 removes the plate-like object 200 before grinding from the cassette 7 and transports it to the alignment unit 40, and also removes the plate-like object 200 after grinding from the cleaning unit 60 and transports it to the cassette 7. The carry-in / out unit 53 is, for example, a robot pick equipped with a U-shaped hand 531, which suction-holds and transports the plate-like object 200.

[0042] The cleaning unit 60 cleans the plate-like object 200 after grinding, and removes foreign matter such as grinding dust adhering to the back surface 201 that has been ground.

[0043] Next, the measurement unit 70 will be described. Fig. 3 is a plan view schematically showing the holding table and measurement unit of the processing apparatus shown in Fig. 1. Fig. 4 is a side view, partially in cross section, schematically showing the holding table and measurement unit shown in Fig. 3. Fig. 5 is a side view, partially in cross section, schematically showing the configuration of a thickness measurement unit of the measurement unit shown in Fig. 3. Fig. 6 is a side view, partially in cross section, schematically showing the configuration of a height measurement unit of the measurement unit shown in Fig. 3.

[0044] 3 and 4, the measuring section 70 includes a measuring arm 71, an angle detector, a thickness measuring unit 80, and a height measuring unit 90. The measuring arm 71 is provided so as to be able to swing about its base end by a drive motor (not shown). By swinging about its base end, the measuring arm 71 moves its tip over the holding surface 61, passing through the center of the holding surface 61 of the holding table 6 positioned at the grinding position. The angle detector detects the angle (direction) of the measuring arm 71 about its base end, and outputs the detection result to the controller 100.

[0045] The thickness measurement unit 80 measures the thickness of the plate-like object 200, which is adsorbed and held on the holding table 6 positioned at the grinding position, in multiple regions while the plate-like object 200 is adsorbed and held on the holding surface 61. The height measurement unit 90 measures the height of the plate-like object 200, which is adsorbed and held on the holding table 6 positioned at the grinding position, in multiple regions while the plate-like object 200 is adsorbed and held on the holding surface 61. In the first embodiment, the thickness measurement unit 80 and the height measurement unit 90 are arranged at the tip of the measuring arm 71, side by side in the circumferential direction around the base end of the measuring arm 71. Note that in the present invention, the thickness measurement unit 80 may measure the thickness of the plate-like object 200, which is adsorbed and held on the holding table 6 positioned at a position other than the grinding position, in multiple regions, and the height measurement unit 90 may measure the height of the plate-like object 200, which is adsorbed and held on the holding table 6 positioned at a position other than the grinding position, in multiple regions.

[0046] The thickness measurement unit 80 is a well-known optical interference measuring instrument, and as shown in Fig. 5, includes a light-projecting unit 81, a spectroscopic unit 82, and a light-receiving unit 83, and is a non-contact thickness measurement unit that measures the thickness of the plate-like object 200 without coming into contact with the plate-like object 200. The light-projecting unit 81 projects measurement light 84 onto the plate-like object 200 held on the holding table 6 positioned at the grinding position. In the first embodiment, the light-projecting unit 81 projects white light containing light of multiple wavelength bands as the measurement light 84 onto the plate-like object 200.

[0047] The spectroscopic unit 82 is configured to separate into light of each wavelength an interference light between reflected light 841 of the measurement light 84 reflected by the back surface 201 of the plate-like object 200 held on the holding table 6 positioned at the grinding position and reflected light 842 of the measurement light 84 reflected by the front surface 202 opposite the back surface 201. The light receiving unit 83 receives light of each wavelength of the interference light separated by the spectroscopic unit 82, and measures the thickness of the plate-like object 200 based on a spectral waveform that is the light intensity of each wavelength received. The light receiving unit 83 outputs the measurement result to the controller 100.

[0048] The height measurement unit 90 is a well-known chromatic aberration confocal sensor, and as shown in Fig. 6, includes a light-projecting unit 91, an optical member 95, a spectroscopic unit 92, and a light-receiving unit 93, and is a non-contact height measurement unit that measures the height of the back surface 201 of the plate-like object 200 without contacting the plate-like object 200. The light-projecting unit 91 irradiates the plate-like object 200 held on the holding table 6 positioned at the grinding position with measurement light 94. In the first embodiment, the light-projecting unit 91 projects white light containing light of multiple wavelength bands as the measurement light 94 onto the plate-like object 200.

[0049] The optical member 95 is disposed opposite to the plate-like object 200 held on the holding table 6 positioned at the grinding position. The optical member 95 generates chromatic aberration along the optical axis direction of the measurement light 94 emitted from the light projecting unit 91, and converges the measurement light 94 with the chromatic aberration generated therein to irradiate the plate-like object 200.

[0050] The spectroscopic unit 92 separates the light reflected and focused by the rear surface 201 of the plate-like object 200 from the other reflected light of the measurement light 94 irradiated onto the plate-like object 200 by the optical member 95. That is, only the light of the wavelength reflected by the rear surface 201 of the measurement light 94 is guided to the spectroscopic unit 92.

[0051] The light receiving unit 93 receives the light of the wavelength reflected by the back surface 201 out of the light dispersed by the spectroscopic unit 92, i.e., the measurement light 94, and measures the height of the back surface 201 of the plate-like object 200. The light receiving unit 93 outputs the measurement result to the controller 100.

[0052] The controller 100 controls each of the above-mentioned constituent units that make up the processing device 1, causing the processing device 1 to execute processing operations on the plate-like object 200. The controller 100 is a computer that has an arithmetic processing device having a microprocessor such as a CPU (central processing unit), a storage device having memory such as a ROM (read only memory) or RAM (random access memory), and an input / output interface device.

[0053] The arithmetic processing unit of the controller 100 performs arithmetic processing in accordance with a computer program stored in the storage device, and outputs control signals for controlling the processing device 1 to the above-mentioned components of the processing device 1 via the input / output interface device. The controller 100 is also connected to a display unit configured with a liquid crystal display device or the like for displaying the status and images of the processing operation, an input unit used by the operator when registering processing content information, and a notification unit for notifying the operator.

[0054] The input unit is composed of at least one of a touch panel provided on the display unit, a keyboard, etc. The notification unit notifies the operator by emitting at least one of sound, light, and a message on the touch panel.

[0055] The controller 100 also includes a processing control unit 101 and a calculation unit 102. The processing control unit 101 controls each component of the processing device 1 to cause the processing device 1 to perform a processing operation on the plate-like object 200.

[0056] The calculation unit 102 calculates the shape of the holding surface 61 of the holding table 6 that holds the plate-like object 200 based on the thickness of the plate-like object 200 in multiple areas measured by the thickness measurement unit 80 and the height of the plate-like object 200 in multiple areas measured by the height measurement unit 90.

[0057] The functions of the machining control unit 101 and the calculation unit 102 are realized by the above-mentioned arithmetic processing unit performing arithmetic processing in accordance with a computer program stored in a storage device.

[0058] Next, a description will be given of a method for inspecting a holding surface according to embodiment 1. Fig. 7 is a flowchart showing the flow of the method for inspecting a holding surface according to embodiment 1. The method for inspecting a holding surface according to embodiment 1 is also a processing operation in which the processing device 1 described above performs grinding, which is a processing, on the plate-like object 200.

[0059] In the first embodiment, the operator places the cassette 7 containing the plate-like object 200 with the back surface 201 facing upward on the cassette mounting table 8 of the apparatus base 2. When the processing conditions are registered in the controller 100 and the controller 100 receives an instruction from the operator to start the processing operation, the processing apparatus 1 starts the processing operation, i.e., the method for inspecting the holding surface according to the first embodiment.

[0060] In embodiment 1, the method for inspecting a holding surface according to embodiment 1 includes an adsorption holding step 1001, a thickness measurement step 1002, a height measurement step 1003, a calculation step 1004, a determination step 1005, and a processing step 1007, as shown in FIG. 7.

[0061] The suction holding step 1001 is a step of suction-holding the plate-like object 200 on the holding surface 61 of the holding table 6. In the first embodiment, in the suction holding step 1001, the processing device 1 causes the processing control unit 101 of the controller 100 to cause the carry-in / out unit 53 to take out one plate-like object 200 from one of the cassettes 7, carry it into the alignment unit 40, and cause the alignment unit 40 to align the center of the plate-like object 200.

[0062] In the first embodiment, in the suction holding step 1001, the processing device 1 causes the processing control unit 101 of the controller 100 to suction and hold the aligned plate-like object 200 on the suction pad 511 of the carry-in unit 51, and causes the carry-in unit 51 to carry it onto the holding surface 61 of the holding table 6 located at the carry-in / out position 301. In the first embodiment, in the suction holding step 1001, the processing device 1 causes the processing control unit 101 of the controller 100 to suction and hold the plate-like object 200 on the holding surface 61 of the holding table 6 located at the carry-in / out position 301.

[0063] The thickness measuring step 1002 is a step of measuring the thickness of the plate-like object 200 held on the holding surface 61 in a plurality of regions, and the height measuring step 1003 is a step of measuring the height of the plate-like object 200 held on the holding surface 61 in a plurality of regions. In the first embodiment, the thickness measuring step 1002 and the height measuring step 1003 are performed simultaneously.

[0064] In the first embodiment, in the thickness measurement step 1002 and the height measurement step 1003, the processing device 1 causes the processing control unit 101 of the controller 100 to rotate the turntable 5 and move the holding table 6 holding the plate-like object 200 at the carry-in / out position 301 to the grinding position 302. In the first embodiment, in the thickness measurement step 1002 and the height measurement step 1003, the processing device 1 causes the processing control unit 101 of the controller 100 to measure the thickness of the plate-like object 200 a predetermined number of times at predetermined intervals with the thickness measurement unit 80 and measure the height of the back surface 201 of the plate-like object 200 a predetermined number of times at predetermined intervals with the height measurement unit 90, while rotating the holding table 6 about its axis as shown in FIG.

[0065] In embodiment 1, in the thickness measurement step 1002 and the height measurement step 1003, the processing device 1 causes the processing control unit 101 of the controller 100 to cause the thickness measurement unit 80 and the height measurement unit 90 to irradiate measurement light 84, 94 at the same position (corresponding to an area) of the plate-like object 200 on the holding surface 61, thereby measuring the thickness and height of the same position of the plate-like object 200 on the holding surface 61, and also measuring the thickness and height of multiple identical positions of the plate-like object 200 on the holding surface 61.

[0066] In the first embodiment, in the thickness measurement step 1002 and the height measurement step 1003, the processing device 1 may have the machining control unit 101 of the controller 100 stop the rotation of the holding table 6 at the grinding position and measure the thickness and height at multiple identical positions. Also, in the present invention, the holding table 6 at the grinding position may be continuously rotated at a constant speed to measure the thickness and height at multiple identical positions. In the present invention, the holding table 6 at the grinding position may be intermittently rotated to measure the thickness and height at multiple identical positions on the holding table 6 while the table is stopped or rotating. Measuring the thickness and height at the same positions of the plate-like object 200 on the holding surface 61 means that the thickness measurement position and the height measurement position may be shifted within a range in which the calculation error of the height of the holding surface 61 calculated in the calculation step 1004 does not result in an error that is undesirable for performing the grinding process.

[0067] Thus, in embodiment 1, the processing device 1 simultaneously performs the thickness measurement step 1002 and the height measurement step 1003, so that the thickness measurement of the plate-like object 200 by the thickness measurement unit 80 and the height measurement of the plate-like object 200 by the height measurement unit 90 are performed simultaneously.

[0068] Calculation step 1004 is a step of calculating the shape of holding surface 61 that holds plate-like object 200 based on the thickness of plate-like object 200 at the multiple positions (corresponding to regions) measured in thickness measurement step 1002 and the height of plate-like object 200 at the multiple positions (corresponding to regions) measured in height measurement step 1003. In embodiment 1, in calculation step 1004, processing device 1 calculates the height of holding surface 61 in the Z-axis direction at each position where thickness measurement unit 80 and height measurement unit 90 measured the thickness and height based on the detection results of thickness measurement unit 80, height measurement unit 90, angle detector, etc. In calculation step 1004, processing device 1 calculates the shape of holding surface 61 by having calculation unit 102 of controller 100 calculate the height of holding surface 61 in the Z-axis direction at each position where thickness measurement unit 80 and height measurement unit 90 measured the thickness and height.

[0069] Determination step 1005 is a step for determining whether or not there is an abnormality in the holding surface 61 calculated in calculation step 1004. For example, in embodiment 1, the presence or absence of an abnormality is determined by determining whether or not there is a scratch on the holding surface 61 or a foreign object on the holding surface 61. In embodiment 1, in determination step 1005, the processing device 1 determines that there is an abnormality in the holding surface 61 (Yes) if the difference between the maximum and minimum values ​​of the heights of the holding surface 61 in the Z-axis direction at each position calculated by the machining control unit 101 of the controller 100 in calculation step 1004 exceeds a predetermined value, and determines that there is no abnormality in the holding surface 61 (No) if the difference is less than the predetermined value.

[0070] In the judgment step 1005, if it is judged that there is an abnormality in the holding surface 61 (Yes), the alarm unit is operated (step 1006), and the holding surface inspection method is terminated. In the judgment step 1005, if it is judged that there is no abnormality in the holding surface 61 (No), the process proceeds to processing step 1007. After the alarm unit is operated, the processing device 1 may have the operator replace the holding table 6 having an abnormality in the holding surface 61, or may grind, i.e., self-grind, the holding surface 61 by the grinding unit 10.

[0071] Processing step 1007 is a step of performing a grinding process on the plate-like object 200 held by suction on the holding surface 61 of the holding table 6. In the first embodiment, in processing step 1007, the processing device 1 causes the processing control unit 101 of the controller 100 to rotate the holding table 6 around its axis, supplies grinding water, and causes the grinding unit 10 to grind the plate-like object 200.

[0072] In the first embodiment, in processing step 1007, after the processing control unit 101 of the controller 100 grinds the plate-like object 200, the processing device 1 rotates the turntable 5 and moves the holding table 6, which holds the ground plate-like object 200 and has stopped rotating around its axis, to the carry-in / out position 301. In the first embodiment, in processing step 1007, the processing device 1 causes the processing control unit 101 of the controller 100 to stop suction holding of the holding table 6 located at the carry-in / out position 301.

[0073] In embodiment 1, in processing step 1007, the processing device 1 causes the processing control unit 101 of the controller 100 to cause the unloading unit 52 to transport the plate-like object 200 after grinding from the holding table 6 at the loading / unloading position 301 to the cleaning unit 60, where it is cleaned and dried, and then causes the unloading unit 53 to store it in the cassette 7.

[0074] In addition, each time the controller 100 rotates the turntable 5 180 degrees, the processing device 1 transports the plate-shaped object 200 from the holding table 6 at the loading / unloading position 301, which holds the plate-shaped object 200 after grinding, to the cleaning unit 60, loads the plate-shaped object 200 before grinding onto the holding table 6 located at the loading / unloading position 301, inspects the holding surface 61 of the holding table 6 located at the grinding position 302, and then grinds the plate-shaped object 200 before grinding held on the holding table 6 located at the grinding position 302.

[0075] In this way, each time the controller 100 rotates the turntable 5 by 180 degrees, the processing device 1 carries out and cleans the plate-like object 200 held on the holding table 6 positioned at the carry-in / out position 301, carries in the plate-like object 200 before grinding onto the holding table 6 positioned at the carry-in / out position 301, and grinds the plate-like object 200 held on the holding surface 61 of the holding table 6 positioned at the grinding position. When the controller 100 has ground all of the plate-like objects 200 in the cassette 7, the processing device 1 ends the processing operation.

[0076] Furthermore, in the present invention, the processing device 1 is not limited to inspecting the holding surface 61 for each plate-like object 200, but can be set, for example, to inspect the holding surface 61 once every five plate-like objects 200 that are ground, or can be set to inspect the holding surface 61 once every 25 plate-like objects 200 (one cassette) that are ground.

[0077] As described above, in the processing device 1 and the holding surface inspection method of embodiment 1, while the plate-like object 200 is held by suction, in a thickness measurement step 1002, the thickness measurement unit 80 measures the thickness of the plate-like object 200 at multiple positions, in a height measurement step 1003, the height measurement unit 90 measures the height of the same multiple positions where the thickness of the plate-like object 200 was measured, and in a calculation step 1004, the calculation section 102 calculates the height in the Z-axis direction of the holding surface 61 of the holding table 6 while the plate-like object 200 is held by suction.

[0078] As a result, the processing device 1 and the method for inspecting a holding surface according to the first embodiment have the effect of making it possible to check the state of the holding surface 61 in a state in which the plate-like object 200 is sucked and held.

[0079] [Embodiment 2] A processing device 1 according to embodiment 2 will be described. Fig. 8 is a side view, partially in cross section, schematically showing the configuration of a height measurement unit of a measurement section of a processing device according to embodiment 2. Fig. 9 is a side view, partially in cross section, schematically showing the configuration of a height measurement unit of a processing device according to a modified example of embodiment 2. The processing device 1 according to embodiment 2 is the same as embodiment 1 except that the configuration of height measurement unit 90-2 is different from that of embodiment 1.

[0080] The height measurement unit 90-2 of the processing device 1 according to the second embodiment is a height measurement unit of the spectral interferometry type, and as shown in Figures 8 and 9, includes a light projecting unit 91, a branching unit 96, a reference mirror 97, a spectroscopic unit 92, and a light receiving unit 93, and is a non-contact height measurement unit that measures the height of the rear surface 201 of the plate-like object 200 without contacting the plate-like object 200. Note that Figure 8 shows a Michelson-type height measurement unit 90-2 of the spectral interferometry type, and Figure 9 shows a Mirau-type height measurement unit 90-2 of the spectral interferometry type.

[0081] The light projecting unit 91 irradiates the plate-like object 200 held on the holding table 6 positioned at the grinding position with measurement light 94. In the second embodiment, the light projecting unit 91 projects white light containing light of multiple wavelength bands as the measurement light 94 onto the plate-like object 200.

[0082] The branching unit 96 branches the measurement light 94 emitted from the light projecting unit 91 into one light 941 and the other light 942. In the first embodiment, the branching unit 96 is a well-known beam splitter. In the second embodiment, an optical member 98 such as a condenser lens is provided between the light projecting unit 91 and the branching unit 96. The reference mirror 97 reflects the measurement light 94 branched by the branching unit 96. The other light 942 is reflected.

[0083] The spectroscopic unit 92 is configured to separate into light of each wavelength an interference light between a reflected light 941 of one of the measurement light 94 branched by the branching unit 96, reflected by the rear surface 201 of the plate-like object 200, and a reflected light 942 of the measurement light 94 branched by the branching unit 96, reflected by the reference mirror 97. The light receiving unit 93 receives light of each wavelength of the interference light separated by the spectroscopic unit 92, and measures the height of the rear surface 201 of the plate-like object 200 based on a spectral waveform that is the light intensity of each wavelength received. The light receiving unit 93 outputs the measurement result to the controller 100.

[0084] As in the first embodiment, the processing device 1 of the second embodiment measures the thickness of the plate-like object 200 at multiple positions on the plate-like object 200 with the thickness measurement unit 80 in a thickness measurement step 1002 while holding the plate-like object 200 by suction, measures the height of the plate-like object at the same multiple positions where the thickness was measured with the height measurement unit 90 in a height measurement step 1003, and calculates the height in the Z-axis direction of the holding surface 61 of the holding table 6 while holding the plate-like object 200 by suction with the calculation section 102 in a calculation step 1004, thereby achieving the effect of being able to confirm the state of the holding surface 61 while holding the plate-like object 200 by suction.

[0085] [Variation 1] A processing device 1 according to Modification 1 of Embodiment 1 and Embodiment 2 will be described. Fig. 10 is a plan view schematically showing a holding table and a measurement unit of a processing device according to Modification 1 of Embodiment 1 and Embodiment 2. Fig. 11 is a side view schematically showing, in partial cross section, the holding table and the measurement unit shown in Fig. 10. In Figs. 10 and 11, the same parts as those in Embodiment 1 and Embodiment 2 are designated by the same reference numerals, and description thereof will be omitted.

[0086] 10 and 11, the processing device 1 according to Modification 1 is the same as Embodiments 1 and 2, except that a plurality of height measurement units 90, 90-2 and a plurality of thickness measurement units 80 are provided. In Modification 1, a plurality of height measurement units 90, 90-2 are provided at intervals in the longitudinal direction of the measuring arm 71, a plurality of thickness measurement units 80 are provided at intervals in the longitudinal direction of the measuring arm 71, and the height measurement units 90, 90-2 and the thickness measurement unit 80 are arranged side by side in the circumferential direction around the base end of the measuring arm 71.

[0087] As in the first and second embodiments, the processing device 1 according to the first modification measures the thickness of the plate-like object 200 at a plurality of positions on the plate-like object 200 with the thickness measurement unit 80 in a thickness measurement step 1002, measures the height of the plate-like object at the same plurality of positions where the thickness was measured with the height measurement units 90 and 90-2 in a height measurement step 1003, and calculates the height in the Z-axis direction of the holding surface 61 of the holding table 6 with the plate-like object 200 being held by suction with the calculation section 102 in a calculation step 1004. As a result, the processing device 1 according to the first modification has the effect of being able to confirm the state of the holding surface 61 with the plate-like object 200 being held by suction.

[0088] The processing device 1 according to the first modification is provided with a plurality of height measurement units 90, 90-2 and thickness measurement units 80, thereby achieving the effect of being able to more accurately check the state of the holding surface 61 when the plate-like object 200 is held by suction. The processing device 1 according to the first modification is provided with a plurality of height measurement units 90, 90-2 and thickness measurement units 80, thereby achieving the effect of being able to measure accurately and to measure in a short time. Note that in the first modification, when measuring the thickness and height of the plate-like object 200 in the thickness measurement step 1002 and the height measurement step 1003, the holding table 6 may rotate without swinging the measurement arm 71.

[0089] [Variation 2] A processing device 1 according to Modification 2 of Embodiment 1 and Embodiment 2 will be described. Fig. 12 is a plan view schematically showing the holding table and measurement unit of the processing device according to Modification 2 of Embodiment 1 and Embodiment 2. Fig. 13 is a side view schematically showing, in partial cross section, the holding table and measurement unit shown in Fig. 12. In Figs. 12 and 13, the same parts as those in Embodiment 1 and Embodiment 2 are designated by the same reference numerals, and description thereof will be omitted.

[0090] As shown in FIGS. 12 and 13, the processing device 1 according to the second modification is the same as those of the first and second embodiments except that, instead of a turntable 5, an X-axis moving unit (not shown) moves a holding table 6 in the X-axis direction, thereby allowing the holding table 6 to move freely between a loading / unloading position 301 and a grinding position 302, and a measuring arm 71 is formed linearly in the Y-axis direction parallel to the horizontal direction and perpendicular to the X-axis direction, and is fixed and positioned above the holding table 6 which moves between the loading / unloading position 301 and the grinding position 302, and a plurality of height measuring units 90, 90-2 and a plurality of thickness measuring units 80 are provided.

[0091] In the present invention, in variant example 2, a measuring arm 71 having a plurality of height measuring units 90, 90-2 and thickness measuring units 80 may be provided between the loading / unloading position and the grinding position on the turntable 5, and the thickness and height of the plate-like object 200 may be measured when the turntable 5 is rotated from the loading / unloading position to the grinding position.

[0092] In addition, in Modification 2, a plurality of height measurement units 90, 90-2 are provided at intervals along the longitudinal direction of measuring arm 71, a plurality of thickness measurement units 80 are provided at intervals along the longitudinal direction of measuring arm 71, and height measurement units 90, 90-2 and thickness measurement unit 80 are arranged side by side in the width direction of measuring arm 71, i.e., the X-axis direction. In Modification 2, in thickness measurement step 1002 and height measurement step 1003, the thickness and height of plate-like object 200 held on holding table 6 are measured by thickness measurement unit 80 and height measurement unit 90, 90-2 while holding table 6 is moved between carry-in / out position 301 and grinding position 302 by the X-axis moving unit.

[0093] As in the first and second embodiments, the processing device 1 according to the second modification measures the thickness of the plate-like object 200 at a plurality of positions on the plate-like object 200 with the thickness measurement unit 80 in a thickness measurement step 1002, measures the height of the plate-like object at the same plurality of positions where the thickness was measured with the height measurement units 90 and 90-2 in a height measurement step 1003, and calculates the height in the Z-axis direction of the holding surface 61 of the holding table 6 with the plate-like object 200 being held by suction with the calculation section 102 in a calculation step 1004. As a result, the processing device 1 according to the second modification has the effect of being able to confirm the state of the holding surface 61 with the plate-like object 200 being held by suction.

[0094] The processing device 1 according to the second modification is provided with a plurality of height measurement units 90, 90-2 and thickness measurement units 80, which has the effect of enabling the state of the holding surface 61 to be more easily confirmed when the plate-like object 200 is held by suction.

[0095] The present invention is not limited to the above-described embodiment. In other words, various modifications can be made without departing from the gist of the present invention. In addition, in the present invention, the thickness measurement step 1002 and the height measurement step 1003 may be performed after the processing step 1007.

[0096] Furthermore, in the present invention, the thickness measurement unit 80 may be a contact-type thickness measurement unit that comes into contact with the back surface 201 and the holding surface 61 of the plate-like object 200 to measure the thickness of the plate-like object 200. Furthermore, the height measurement unit 90 is not limited to a chromatic aberration confocal sensor or the like, and may be, for example, a laser displacement meter or the like. [Explanation of symbols]

[0097] 1 Processing equipment 6 Holding table 61 Holding surface 80 Thickness measurement unit 81 Light projector 82 Spectroscopic section 83 Light receiving part 84 Measurement Light 90,90-2 Height Measuring Unit 91 Light projector 92 Spectroscopic section 93 Light receiving part 94 Measurement Light 95 Optical Components 96 Branch 97 Reference Mirror 100 Controllers 102 Calculation section 200 Plate-shaped objects 201 Back side (one side) 202 Surface (other side) 841 Reflected light 842 Reflected light 941 One side of the light 942 The other light 1001 Adsorption holding step 1002 Thickness measurement step 1003 Height measurement step 1004 Calculation Steps

Claims

1. a holding table having a holding surface that suction-holds a plate-like object having one surface and another surface opposite to the one surface in a state where the one surface is exposed; a processing unit that performs a predetermined process on the plate-like object held on the holding table; a thickness measurement unit that measures the thickness of the plate-like object in a plurality of regions while the plate-like object is held by suction on the holding surface; a height measurement unit that measures the height of the plate-like object in a plurality of regions while the plate-like object is held by suction on the holding surface; a controller; The controller Based on the thicknesses of the plate-like object in the multiple regions measured by the thickness measuring unit and the heights of the plate-like object in the multiple regions measured by the height measuring unit, a processing device having a calculation unit that calculates the shape of the holding surface of the holding table that holds the plate-like object;

2. measuring the thickness of the plate-like object by the thickness measuring unit; 2. The processing apparatus according to claim 1, wherein the height measurement unit measures the height of the plate-like object simultaneously.

3. 3. The processing apparatus according to claim 1, wherein a plurality of the thickness measuring units and a plurality of the height measuring units are provided.

4. The thickness measurement unit comprises: a light projecting unit that projects measurement light onto the plate-like object; a spectroscopic unit for separating interference light between reflected light reflected from one surface of the plate-like object and reflected light reflected from another surface opposite to the one surface; 3. The processing apparatus according to claim 1, wherein the processing apparatus is a non-contact thickness measurement unit including: a light receiving section that receives the interference light dispersed by the spectroscopic section.

5. The height measurement unit a light projecting unit that projects measurement light having a plurality of wavelength bands onto the plate-like object; an optical member that generates chromatic aberration along the optical axis direction of the light emitted from the light projecting unit and converges the light to irradiate the plate-like object; a spectroscopic unit that spectroscopically separates light that is irradiated onto the plate-like object by the optical member and focused and reflected on one surface of the plate-like object; 3. The processing device according to claim 1, wherein the processing device is a non-contact height measurement unit including: a light receiving section that receives the light dispersed by the spectroscopic section.

6. The height measurement unit a light projecting unit that projects measurement light onto the plate-like object; a splitter that splits the light emitted from the light projector into one light and another light; a spectroscopic unit for separating interference light between a reflected light of one of the beams split by the splitting unit and reflected by one surface of the plate-like object and a reflected light of the other of the beams split by the splitting unit and reflected by a reference mirror; 3. The processing device according to claim 1, wherein the processing device is a non-contact height measurement unit including: a light receiving section that receives the interference light dispersed by the spectroscopic section.

7. a suction holding step of suction-holding the plate-like object on a holding surface of the holding table; a thickness measuring step of measuring the thickness of the plate-like object held on the holding surface in a plurality of regions; a height measuring step of measuring the height of the plate-like object held on the holding surface in a plurality of regions; a calculation step of calculating a shape of a holding surface that holds the plate-like object based on the thicknesses of the plate-like object in the multiple regions measured in the thickness measurement step and the heights of the plate-like object in the multiple regions measured in the height measurement step; A method for inspecting a holding surface, comprising:

8. 8. The method for inspecting a holding surface according to claim 7, wherein the thickness measuring step and the height measuring step are performed simultaneously.

Images