Processing device

Abstract

To provide a processing device that can stably acquire cross-sectional profile of a processing groove.SOLUTION: A processing device for processing a workpiece includes an optical interference type microscope moving in a vertical direction relative to the workpiece and measures a profile with the optical interference type microscope under a measurement condition of avoiding an oscillation period of the processing device.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a processing device. [Background technology]

[0002] A workpiece (workpiece) such as a semiconductor wafer has multiple devices partitioned into a grid by grid-like streets. Individual devices are manufactured by dividing the workpiece along the streets. A blade dicer is well known as a dicing device for dividing a workpiece into multiple devices (chips) (see Patent Document 1). This blade dicer moves a blade that rotates at high speed relative to the workpiece, forming grooves along the streets with this blade. The dicing device in Patent Document 1 measures the shape of the grooves by white light interferometry using a white light interference microscope. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-084201 Summary of the Invention [Problem to be solved by the invention]

[0004] The workpiece diced by the dicing device described in Patent Document 1 is divided into individual chips by expanding the dicing tape in a known expanding process. The individual chips are then picked up in a known pick-up process. During this process, the dicing device described in the Patent Document uses a three-dimensional shape measuring unit to manage the shape of the processed grooves.

[0005] In systems that precisely measure the surface shape of an object using a white light interferometer or similar, measures are taken to prevent vibration from occurring in the device or to reduce the vibration level by eliminating the need for a vibration source or by placing the measurement unit on a vibration isolation table.

[0006] However, machining devices equipped with a measuring unit and a machining unit have moving parts such as a machining spindle and a cleaning unit, which become sources of vibration during measurement. It is difficult to slow down or stop these moving parts from the viewpoint of the workpiece machining quality and the process. Therefore, it is difficult to prevent or reduce the vibration of the moving parts and suppress the impact of the vibration on the measuring unit.

[0007] The present invention has been made in view of the above circumstances, and has an object to provide a processing device that can stably obtain a cross-sectional profile of a processed groove. [Means for solving the problem]

[0008] The gist of the present invention is as follows. <1> A processing device according to one aspect of the present invention is a processing device that processes a workpiece, and is equipped with an optical interference microscope that moves vertically relative to the workpiece, and measures a profile using the optical interference microscope using measurement conditions that avoid the vibration period of the processing device. <2> the above <1> In the processing device described above, the measurement conditions that avoid the vibration period may be obtained by calculating the vibration period of the processing device from a reference workpiece onto which light is irradiated and an interference signal based on reflected light from the reference workpiece. <3> the above <2> In the machining apparatus described above, the reference workpiece may have a plurality of surfaces inclined relative to a horizontal plane, and the inclined surfaces may be inclined in directions perpendicular to each other on the horizontal plane. <4> the above <1> ~ <3> In any one of the processing apparatuses described above, the measurement conditions that avoid the vibration period of the processing apparatus may include at least one of a scanning speed, a frame rate, and a measurement pitch. [Effects of the Invention]

[0009] According to the present invention, the cross-sectional profile of the machined groove can be stably obtained. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a perspective view of a processing device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of a processing unit in the processing device according to the embodiment. [Figure 3] FIG. 2 is a cross-sectional view of the optical interference microscope according to the embodiment. [Figure 4] 1A and 1B are diagrams showing a schematic view of a cross section of a processed groove and an example of a cross-sectional profile; [Figure 5] FIG. 2 is a schematic diagram of a reference workpiece in the same embodiment. [Figure 6] FIG. 2 is a block diagram of a processing device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, a processing device according to one embodiment of the present invention will be described with reference to the drawings. In the following embodiments, when the number, numerical value, amount, range, etc. of components are mentioned, unless otherwise specified or when it is clearly limited to a specific number in principle, the number is not limited to the specific number, and may be more or less than the specific number.

[0012] Furthermore, when referring to the shape or positional relationship of components, etc., it includes things that are substantially similar or approximate to those shapes, etc., unless otherwise specified or when it is clearly considered otherwise in principle.

[0013] In addition, the drawings may exaggerate characteristic parts to make the features easier to understand, and the dimensional proportions of the components may not be the same as in reality. In addition, in cross-sectional views, hatching of some components may be omitted to make the cross-sectional structure of the components easier to understand.

[0014] 1 is a perspective view of a processing apparatus 10 according to one embodiment of the present invention. Note that the X, Y, and Z directions in the figure are mutually orthogonal, with the X and Y directions being parallel to the horizontal direction and the Z direction being orthogonal to the horizontal direction (the vertical direction in the present invention).

[0015] As shown in Figure 1, processing apparatus 10 performs dicing on a flat workpiece W such as a silicon wafer (semiconductor wafer). Processing apparatus 10 measures the profile using an optical interference microscope 24 (described later) under measurement conditions that avoid the vibration period. This processing apparatus 10 includes a load port 12, a transport mechanism 14, a processing unit 16, and a cleaning unit 18. The workpiece W is an example of a workpiece.

[0016] A cassette containing a large number of workpieces W mounted on a frame F is placed on the load port 12. A transport mechanism 14 transports the workpieces W. A processing unit 16 dices the workpieces W. A cleaning unit 18 spin-cleans the diced workpieces W. Inside the housing 10A of the processing device 10, there is provided a control device 60 (see FIG. 6) that controls the operation of each part of the processing device 10. Note that the control device 60 may be provided outside the housing 10A.

[0017] The unmachined workpiece W stored in a cassette placed on the load port 12 is transported by the transport mechanism 14 to the processing unit 16, where it is subjected to dicing such as cutting or grooving to separate it into individual chips. The workpiece W processed by the processing unit 16 is then transported by the transport mechanism 14 to the cleaning unit 18, where it is cleaned, and then transported by the transport mechanism 14 to the load port 12 and stored in a cassette.

[0018] Fig. 2 is an external perspective view of processing unit 16. As shown in Fig. 2, processing unit 16 is a twin-spindle dicer, and includes a pair of blades 21A and 21B, a blade cover (not shown), a pair of spindles 22A and 22B, a microscope 23, an optical interference microscope 24, and a table 31.

[0019] Blades 21A and 21B are formed in a disk shape. The tip shapes of blades 21A and 21B, i.e., the cross-sectional shapes of the outer peripheries (cutting edges) of blades 21A and 21B along the radial direction of blades 21A and 21B, are rectangular (other shapes such as V-shapes are also acceptable). Blades 21A and 21B are arranged opposite each other in the Y direction and are held by spindles 22A and 22B so as to be rotatable about blade rotation axes parallel to the Y direction.

[0020] The spindles 22A and 22B incorporate high-frequency motors, which rotate the blades 21A and 21B at high speed around the blade rotation axis, thereby dicing (cutting) each street of the workpiece W from the surface (device formation surface) side of the workpiece W by the blades 21A and 21B, forming machined grooves.

[0021] The microscope 23 is provided on a Z carriage 44 integrally with, for example, the spindle 22A (or spindle 22B), and is held by the Y carriage 43 and the Z carriage 44 so as to be movable in the Y and Z directions integrally with the spindle 22A. The microscope 23 photographs the pattern and machined grooves on the surface of the workpiece W from the front side of the workpiece W. The image of the surface of the workpiece W photographed by this microscope 23 is used for aligning the blades 21A and 21B with the streets of the workpiece W, and for a kerf check to confirm the position of the machined grooves.

[0022] The optical interference microscope 24 is mounted on the Z carriage 44 integrally with the spindle 22B (or spindle 22A), and is held by the Y carriage 43 and the Z carriage 44 so as to be freely movable in the Y and Z directions. The optical interference microscope 24 is used to acquire a group of three-dimensional coordinate data (also called point cloud data) that represents the shape (three-dimensional shape) of the machined groove. The group of three-dimensional coordinate data is used to calculate the cross-sectional profile of the machined groove and to confirm the undivided state of the DAF 7.

[0023] In this embodiment, the microscope 23 and the optical interference microscope 24 are provided as separate bodies, but they may be integrated together.

[0024] The table 31 has a workpiece holding surface 31a formed to be porous, and this workpiece holding surface 31a adsorbs and holds the workpiece W from the back side of the workpiece W via a dicing tape 9 or the like. The table 31 is held by an X carriage 36 (described later) so as to be movable in the X direction, and is held by a rotation unit 37 (described later) so as to be rotatable about a rotation axis CA.

[0025] Processing section 16 is provided with X base 32, X guide 34, X drive section 35, X carriage 36, and rotation unit 37. X base 32 has a flat plate shape extending in the X direction, and X guide 34 is provided on its upper surface in the Z direction. X guide 34 has a shape extending in the X direction, and guides X carriage 36 along the X direction. X drive section 35 uses an actuator such as a linear motor, and moves X carriage 36 in the X direction along X guide 34.

[0026] The rotation unit 37 is provided on the upper surface of the X-carriage 36. The table 31 is provided on the upper surface of the rotation unit 37. The rotation unit 37 is driven to rotate by a rotation drive unit (not shown) that is composed of a motor, gears, etc. This causes the rotation unit 37 to rotate the table 31 in the θ direction around its rotation axis CA. A reference workpiece 80 is provided on the table 31, the details of which will be described later.

[0027] Processing unit 16 is also provided with a Y base 41, a Y guide 42, a pair of Y carriages 43, and a pair of Z carriages 44. Y base 41 has a gate-like shape that straddles X base 32 in the Y direction. Y guide 42 is provided on the side surface of Y base 41 on the X direction side. Y guide 42 has a shape that extends in the Y direction, and guides each of the pair of Y carriages 43 along the Y direction. The pair of Y carriages 43 are moved independently along Y guide 42 by Y drive unit 45 (see FIG. 6) that is configured, for example, by a stepping motor, a ball screw, etc.

[0028] A Z carriage 44 is provided on each of the pair of Y carriages 43 so as to be movable in the Z direction via a Z drive unit 46 (see FIG. 6) configured with an actuator such as a stepping motor. Spindle 22A and microscope 23 are provided on one side of Z carriage 44, and spindle 22B and optical interference microscope 24 are provided on the other side of Z carriage 44.

[0029] When dicing the workpiece W, each part of the processing unit 16 is driven to perform cutting feed of the workpiece W in the X direction (processing feed direction), and index feed of the blades 21A and 21B in the Y direction and cutting feed in the Z direction, thereby forming processing grooves along each street of the workpiece W.

[0030] Fig. 3 is a cross-sectional view showing an example of an optical interference microscope according to this embodiment. As shown in Fig. 3, the optical interference microscope 24 is a Mirau-type white light interferometer that measures the cross-sectional profile of a machined groove using white light interferometry. The optical interference microscope 24 includes a housing 50, a light source 51, a first beam splitter 52, an objective lens 53, a glass plate 54, a second beam splitter 55, and an imaging unit 56.

[0031] The housing 50 accommodates a first beam splitter 52, an objective lens 53, a glass plate 54, and a second beam splitter 55. Inside the housing 50, the second beam splitter 55, the glass plate 54, the objective lens 53, and the first beam splitter 52 are arranged from the bottom to the top in the Z direction. A light source 51 is attached to a side surface of the housing 50 at a position to the side of the first beam splitter 52. An imaging unit 56 is attached to the top surface of the housing 50 at a position above the first beam splitter 52.

[0032] The light source 51 emits output light L1 toward the first beam splitter 52 while the optical interference microscope 24 is vertically scanned in the Z direction relative to the table 31 (workpiece W). The output light L1 is light with a range of wavelengths and is sometimes called white light. The first beam splitter 52 reflects a portion of the output light L1 incident from the light source 51 toward the objective lens 53. The first beam splitter 52 also transmits a portion of the interference light L4 (described below) incident from the objective lens 53, and emits it toward the imaging unit 56.

[0033] The objective lens 53 focuses the emitted light L1 incident from the first beam splitter 52 onto the workpiece W.

[0034] The glass plate 54 has a mirror 54a in its center that functions as a reference surface. The glass plate 54 (excluding the mirror 54a) transmits the outgoing light L1 incident from the objective lens 53 as is and emits it toward the second beam splitter 55.

[0035] The second beam splitter 55 splits the output light L1 collected by the objective lens 53 into measurement light L2 and reference light L3, and transmits the measurement light L2 to irradiate the surface of the workpiece W while reflecting the reference light L3 toward the mirror 54a. The measurement light L2 transmitted through the second beam splitter 55 is reflected by the surface of the workpiece W and the surface of the machined groove (groove wall surface and groove bottom surface) and enters the second beam splitter 55. The reference light L3 reflected by the mirror 54a enters the second beam splitter 55 and is partially reflected by the second beam splitter 55. This generates interference light L4 between the measurement light L2 and the reference light L3. This interference light L4 passes through the glass plate 54, the objective lens 53, and the first beam splitter 52 and enters the imaging unit 56.

[0036] Here, the optical path length of the reference light L3 is constant, but the optical path length of the measurement light L2 changes in response to the vertical scanning of the optical interference microscope 24. When the objective lens 53 is focused on various objects to be measured (here, the surface of the workpiece W and the machined groove), the difference in the optical path lengths of the measurement light L2 and the reference light L3 becomes zero (including nearly zero), and the interference between the measurement light L2 and the reference light L3 becomes constructive. As a result, the signal intensity of the interference light L4 increases. The position of the surface of the workpiece W is measured, for example, using the technology described in JP 2017-106860 A.

[0037] The imaging unit 56 includes a two-dimensional imaging element of the CCD (Charge Coupled Device) type or CMOS (Complementary Metal Oxide Semiconductor) type in which a plurality of pixels (light receiving elements) are two-dimensionally arranged in the X and Y directions. While the optical interference microscope 24 is vertically scanned in the Z direction once or multiple times by the Z drive unit 46 (see FIG. 6 ), the imaging unit 56 captures the interference light L4 incident from the first beam splitter 52 for each pixel of the two-dimensional imaging element, thereby detecting (acquiring) the interference light L4 for each pixel and outputting the interference light L4 for each pixel to the control device 60.

[0038] Fig. 4(A) shows a schematic diagram of the cross section of the machined groove g of the workpiece W to be measured, Fig. 4(B) shows an example of a properly measured cross-sectional profile, and Fig. 4(C) shows an example of a cross-sectional profile that was not properly measured. If the effect of vibration on the device is small, the cross-sectional profile can be measured as shown in Fig. 4(B), but if the device is vibrating, the cross-sectional profile may not be measured accurately, as shown in Fig. 4(C).

[0039] As described above, when a processing device includes a measurement unit and a processing unit, it is not possible to eliminate or reduce vibrations from the spindle or cleaning unit of the processing unit, making it impossible to stably measure cross-sectional profiles with high accuracy. The inventors investigated the relationship between cross-sectional profile measurement failures and device vibration and found that measurement failures are related to the flickering frequency due to the vertical scanning speed and frame rate of the optical interference microscope and the vibration frequency of the device. They also found that measurement failures occur when the vibration frequency of the device is close to the flickering frequency at the frame rate during measurement. Therefore, they found that cross-sectional profiles can be stably measured using an optical interference microscope by shifting the flickering frequency at the frame rate during measurement from the vibration frequency of the device. This is explained in detail below. Note that the various values ​​in the following explanation are merely examples, and the present invention is not limited thereto.

[0040] For example, if the central wavelength of the emitted light L1 is 560 nm, the wavelengths of the measurement light L2 and reference light L3 are also 560 nm. Also, assume that the depth of the machined groove is 200 μm and the vertical scanning speed (scanning speed) of the optical interference microscope 24 is 10 μm / sec. In this case, the time required to irradiate the measurement light L2 onto the workpiece W and obtain the cross-sectional profile of the machined groove is 200 (μm) / 10 (μm / sec) = 20 (sec).

[0041] Assuming that the imaging pitch of the imaging unit 56 is 20 nm / frame, the number of images of a processed groove with a depth of 200 μm is 200 (μm) / 20 (nm / frame)=10,000. Therefore, the frame rate of the imaging unit 56 under these conditions is 10,000 (frames) / 20 (seconds)=500 (frames / second).

[0042] Here, if the distance from the second beam splitter 55 to the surface of the workpiece W is d, the wavelength of the measurement light L2 is 560 nm, so the measurement light L2 and reference light L3 reinforce each other every d = 280 nm, resulting in a bright image. Since the measurement pitch is 20 nm per sheet, light and dark are repeated (blinking) every 280 (nm) / 20 (nm / sheet) = 14 sheets.

[0043] Since the frame rate is 500 frames / second, the blinking period is 14 frames / 500 frames / second = 0.028 seconds, and the frequency is approximately 35.7 Hz. If this frequency is similar to the vibration frequency of the device, a normal cross-sectional profile cannot be obtained, as shown in Figure 4(C).

[0044] Table 1 shows the cross-sectional profile measurement results when the cleaning unit spinner was rotated at the rotation speed shown in Table 1 using output light L1 with a central wavelength of 560 nm and the optical interference microscope 24 was scanned at the scanning speed shown in Table 1. Note that "-" in Table 1 indicates that the cross-sectional profile was not measured.

[0045] [Table 1]

[0046] As shown in Table 1, when the spinner rotation speed was 1152 rpm, a cross-sectional profile could not be obtained at a scanning speed of 5.8 μm / s. In this case, the spinner frequency was 19.2 Hz, and the flickering frequency in the image acquired by the optical interference microscope was 20.6 Hz. Also, when the spinner rotation speed was 2000 rpm, a cross-sectional profile could not be obtained at a scanning speed of 10.1 μm / s. In this case, the spinner frequency was 33.3 Hz, and the frequency of the interference fringes in the image acquired by the optical interference microscope was 35.9 Hz.

[0047] Since the spinner frequency can be considered the spinner vibration frequency, if the blinking frequency is close to the spinner vibration frequency, a normal cross-sectional profile cannot be obtained. Therefore, a normal cross-sectional profile can be obtained by adjusting the vertical scanning speed of the optical interference microscope 24 to shift the light and dark frequency from the spinner vibration frequency. Since equipment vibrations are caused not only by the spinner but also by other vibration sources such as the spindle and vacuum pump, it is important to shift the light and dark frequency from the vibration frequency of the equipment's vibration sources. Furthermore, it is also important to shift the light and dark frequency from the superimposed vibrations from multiple vibration sources.

[0048] Therefore, to prevent measurement failure, the frequency of the machine vibration is measured in advance, and the measurement conditions are determined so that the blinking frequency of the optical interference microscope 24 is a frequency that is far from the measured machine vibration frequency. This makes it possible to stably measure the cross-sectional profile of the workpiece W using the optical interference microscope even if the processing machine 10 is vibrating.

[0049] The machining apparatus 10 according to this embodiment is provided with a reference workpiece 80 for measuring the frequency of the vibration of the apparatus in advance. The reference workpiece 80 is, for example, as shown in FIG. 5, a plane S perpendicular to the Z-axis direction (vertical scanning direction). z The reference workpiece 80 has a shape of a quadrangular pyramid with a surface S inclined in the X-axis direction. x and the surface S inclined in the Y-axis direction Y It has.

[0050] The reference workpiece 80 is used to calculate the vibration period of the processing device 10. Light is irradiated onto the reference workpiece 80, and the vibration period of the processing device 10 is calculated from an interference signal based on the light reflected from the reference workpiece 80. The measurement conditions for the profile are set so as to avoid the calculated vibration period of the processing device 10. In detail, when the relative position between the optical interference microscope 24 and the reference workpiece 80 vibrates in the X, Y, and Z directions, the interference fringes on the reference workpiece 80 viewed by the optical interference microscope 24 oscillate according to the displacement and frequency of the vibration. When the optical interference microscope 24 emits the emitted light L1 from the light source 51 to the reference workpiece 80, and the imaging unit 56 captures the interference light L4 and outputs the interference signal, the surface S x In this case, the brightest line is displayed at the focal position, and a bright line appears every time the light is shifted from the focal position in the Z direction by half the wavelength of light, and a dark line appears between each bright line. The brightness of the bright lines decreases as the distance from the focal position increases. Such interference fringes are formed on the surface S x When the relative position of the optical interference microscope 24 and the reference workpiece 80 changes due to vibration, the image of the interference fringes displayed on the monitor 70 (see FIG. 6) oscillates in accordance with the frequency of vibration in the x direction of the device. Here, the frequency of vibration in the x direction can be calculated by Fourier transforming the blinking signal due to the oscillation of the interference fringes caused by the interference light L4 acquired by the imaging unit 56. Surface S Y Similarly, the frequency of vibration in the Y direction can be calculated for plane S. z In this case, the frequency of the vibration in the Z direction can be calculated by performing a Fourier transform on the signal intensity of the interference light L4 acquired by the imaging unit 56 based on the frequency of the blinking. However, surface S x The fluctuation of the interference fringes of the surface S contains two components, vibration in the Z direction and vibration in the X direction. Y The oscillation of the interference fringes includes two components, namely, vibration in the Z direction and vibration in the Y direction. z The vibration frequency in the Z direction is calculated from the flickering of the interference fringes, and then the vibration frequency in the Z direction is calculated from the flickering of the interference fringes. xThe vibration frequencies in the Z and X directions are calculated from the fluctuations of the interference fringes. The component of the Z and X vibration frequencies that differs from the previously calculated Z vibration frequency is calculated as the X vibration frequency. The Y vibration frequency is calculated in the same way. If only the vibration frequency of the processing device 10 is concerned, there is no need to separate the two components of the vibration, so it is sufficient to analyze only the two slopes.

[0051] Then, by setting the observation conditions of the optical interference microscope 24 so that the blinking frequency at the frame rate during measurement is shifted from the frequencies of the device vibration in the X, Y, and Z directions, it becomes possible to obtain a stable cross-sectional profile. The observation conditions include the vertical scanning speed, ROI, measurement pitch, and wavelength of the emitted light L1.

[0052] The reference workpiece 80 is placed on the table 31. Since the workpiece W is placed on the table 31, the reference workpiece 80 is subjected to vibrations similar to those experienced by the workpiece W when the reference workpiece 80 is placed on the table 31. Therefore, it is possible to reflect the vibrations of the device experienced by the workpiece W.

[0053] In this embodiment, a Mirau interferometer has been used as an example of the optical interference microscope 24, but various interferometers (interference microscopes) used to measure the shapes of various objects to be measured, such as a Michelson interferometer, may also be used.

[0054] Fig. 6 is a block diagram of the processing apparatus 10 of the first embodiment. As shown in Fig. 6, a control device 60 of the processing apparatus 10 controls each part of the processing apparatus 10. The load port 12, the transfer mechanism 14, the processing unit 16, and the cleaning unit 18, which have already been described, are connected to this control device 60. Note that the load port 12, the transfer mechanism 14, and the cleaning unit 18 are omitted from Fig. 5.

[0055] The control device 60 may be, for example, a personal computer (PC), and may include an arithmetic circuit configured with various processors, memories, etc. The various processors include a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), and a programmable logic device. Examples of programmable logic devices include simple programmable logic devices (SPLD), complex programmable logic devices (CPLD), and field programmable gate arrays (FPGA). The various functions of the control device 60 may be implemented by a single processor, or by multiple processors of the same or different types.

[0056] The control device 60 executes a control program (not shown) to function as a device control unit 61, a calculation unit 62, and a processing unit 63. The control program is stored in, for example, a storage unit (not shown).

[0057] When measuring the apparatus vibration, the apparatus control unit 61 controls the drive units 35, 45, and 46 to adjust the position of the optical interference microscope 24 so that it is positioned above the reference workpiece 80. Next, the apparatus control unit 61 continuously causes the light source 51 to emit light L1, and the imaging unit 56 to capture the interference light L4 and output an interference signal. While the optical interference microscope 24 and the reference workpiece 80 are vibrating relative to each other, the two-dimensional imaging element of the imaging unit 56 continuously outputs an interference signal for each pixel to the control device 60.

[0058] The calculation unit 62 calculates the frequency of vibration of the device based on an interference signal based on the light (measurement light L2) reflected from the reference workpiece 80. The method for calculating the frequency of vibration of the device is as described above.

[0059] When dicing the workpiece W, the device control unit 61 controls each part of the processing unit 16 (the driving units 35, 45, 46, the microscope 23, and the spindles 22A, 22B, etc.) to perform known alignment, and then performs cutting along each street to form processed grooves. Note that the specific method of dicing is a known technique, so a detailed description will be omitted here.

[0060] Furthermore, after dicing one or more streets or all streets of the workpiece W, the device control unit 61 controls each part of the processing unit 16 (such as the drive units 35, 45, and 46 and the optical interference microscope 24) to measure the shape of the diced groove. For example, the device control unit 61 controls the drive units 35, 45, and 46 to adjust the position of the optical interference microscope 24 relative to the workpiece W so that the optical interference microscope 24 is positioned above the diced groove in the Z direction. Next, the device control unit 61 controls the Z drive unit 46 to vertically scan the optical interference microscope 24 in the Z direction, while continuously emitting the emitted light L1 from the light source 51 and capturing the interference light L4 with the imaging unit 56 and outputting an interference signal. While the optical interference microscope 24 and the reference workpiece 80 are vibrating relative to each other, the two-dimensional imaging element of the imaging unit 56 continuously outputs an interference signal for each pixel to the control device 60. The device control unit 61 then repeatedly changes the position of the optical interference microscope 24 in the X and Y directions relative to the workpiece W, vertically scans the optical interference microscope 24, and captures the interference light L4 with the imaging unit 56 and outputs an interference signal, so that shape measurement of the machined groove can be performed for any street on the workpiece W. At this time, for example, the scanning speed of the optical interference microscope 24 is set so that the frequency of the blinking is shifted from the frequency of the device vibration.

[0061] The processing unit 63 calculates the cross-sectional profile of the processed groove based on the interference signal output for each pixel from the two-dimensional image sensor of the imaging unit 56 during vertical scanning of the optical interference microscope 24. The calculation of the cross-sectional profile may be performed by a known method.

[0062] According to the above embodiment, the vibration frequency of the machine is calculated in advance using the reference workpiece 80, and the measurement conditions are determined so that the blinking frequency in the vertical scan of the optical interference microscope 24 is a frequency that is far from the measured machine vibration frequency. This makes it possible to stably measure the cross-sectional profile of the workpiece W using the optical interference microscope, even if the processing machine 10 is vibrating.

[0063] The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

[0064] For example, in the above embodiment, the central wavelength of the emitted light L1 is set to 560 nm, but the central wavelength is not limited to 560 nm and may be selected appropriately.

[0065] Furthermore, the components in this embodiment can be replaced with well-known components as appropriate without departing from the spirit of the present invention. [Explanation of symbols]

[0066] 10 Processing equipment 10A housing 12 Loading Port 14 Transport mechanism 16 Processing Department 18 Cleaning section 21A Blade 21B Blade 22A spindle 22B spindle 23 Microscope 24 Optical interference microscope 31 Table 31a Work holding surface 32 X Base 34 X Guide 35 X drive unit 36 x Carriage 37 Rotating Unit 41 Y Base 42 Y guide 43 Y carriage 44 Z carriage 45 Y drive unit 46 Z drive unit 50 Housing 51 Light source 52 First beam splitter 53 Objective Lens 54 Glass Plate 54a Mirror 55 Second beam splitter 56 Imaging unit 60 Control device 61 Device control section 62 Calculation section 63 Processing section 70 monitors 80 Standard Work

Claims

1. A processing device for processing a workpiece, an optical interference microscope that moves in a direction perpendicular to the workpiece; A processing device that measures a profile with the optical interference microscope using measurement conditions that avoid the vibration period of the processing device.

2. The measurement conditions that avoid the vibration period are:

2. The machining device according to claim 1, wherein the vibration period of the machining device is calculated from an interference signal based on a reference workpiece onto which light is irradiated and light reflected from the reference workpiece.

3. the reference workpiece has a plurality of surfaces inclined relative to a horizontal plane, The processing device according to claim 2 , wherein the inclined surfaces are inclined in directions perpendicular to each other on the horizontal plane.

4. 4. The processing device according to claim 1, wherein the measurement conditions that avoid the vibration period of the processing device include at least one of a scanning speed, a frame rate, and a measurement pitch.

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