Laser processing method and laser processing apparatus

Abstract

The invention provides a laser processing method and a laser processing apparatus, which can improve throughput when laser ablation processing is performed on a workpiece. The laser processing method includes: a protective film detection step of measuring a protective film coated on a workpiece disposed on a processing table to acquire data related to the protective film; a positioning step for determining the position of the workpiece; and a processing step of performing laser processing on the processing line of the workpiece, in the positioning step, the data related to the protective film acquired in the protective film detection step is used in at least a part of the position detection of the workpiece.

Description

Technical Field

[0001] The invention relates to a laser processing method and a laser processing device. Background Art

[0002] For example, a laser processing method is known that uses laser ablation to cut a wafer having a device layer formed thereon. According to this laser processing method, during laser ablation of the wafer, molten debris may be generated and adhere to the device layer. As a countermeasure, a protective film can be formed on the surface of the wafer before laser ablation. After laser ablation, the protective film can be rinsed to remove the debris along with the protective film. This prevents the debris from adhering to the device layer.

[0003] Here, the protective film is applied to the surface of the wafer by spin coating, for example, while the wafer is placed on a coating station. The protective film may sometimes have areas where the coating is poor or residual, or may have an abnormal film thickness. In this case, the debris directly adheres to the device layer at the area where the coating is poor or residual, causing a defective wafer. In addition, when the film thickness is too thick, the transmission of the laser is blocked by the protective film, causing poor processing. When the film thickness is too thin, similar to the case of poor coating or residual coating, the debris directly adheres to the device layer at the area where the film thickness is too thin, causing a defective wafer. Therefore, in order to improve the yield when performing laser ablation processing on the wafer, it is important to check whether the protective film has poor coating or residual coating and abnormal film thickness before processing the wafer.

[0004] That is, after applying the protective film on the wafer placed on the coating station, the protective film is observed and the coating condition is checked. If the inspection results show that the protective film has no coating defects, coating residues, or abnormal film thickness, the wafer is transferred from the coating station and placed on the processing station.

[0005] The wafer, placed on a processing table, is roughly aligned by observing it at low magnification using an alignment microscope. After coarse alignment, the wafer is observed at high magnification using an alignment microscope and fine alignment is performed to precisely position the wafer. After fine alignment, laser ablation is performed to cut the processing lines on the wafer (see, for example, Patent Document 1).

[0006] Patent Document 1: Japanese Patent Publication No. 2022-178427

[0007] However, conventional laser processing methods inspect the protective film while the wafer is set on the coating table. After inspection, the wafer is moved and set on the processing table, where coarse and fine alignment of the set wafer is performed. Specifically, conventional laser processing methods perform the protective film inspection and wafer alignment as separate inspection steps. Consequently, laser ablation of wafers (i.e., workpieces) takes time, leaving room for improvement in terms of throughput. Summary of the Invention

[0008] The present invention has been made in view of the above-mentioned situation, and an object of the present invention is to provide a laser processing method and a laser processing device, which can improve the throughput when performing laser ablation processing on a workpiece.

[0009] In order to solve the above problems, the present invention proposes the following solutions.

[0010] <1> The laser processing method of one aspect of the present invention includes: a protective film detection step, measuring the protective film coated on the workpiece to obtain data related to the protective film, wherein the workpiece is set on a processing table; a positioning step, determining the position of the workpiece; and a processing step, performing laser processing on the processing line of the workpiece, in which, in the positioning step, the data related to the protective film obtained by the protective film detection step is used in at least a part of the detection of the position of the workpiece.

[0011] <2> In the above <1> In the laser processing method, the positioning process may include a shape measurement process, a rough alignment process, and a fine alignment process, and data related to the protective film is used in at least one of the shape measurement process, the rough alignment process, and the fine alignment process.

[0012] <3> In the above <1> or <2> In the laser processing method, the data related to the protective film may include at least one of two-dimensional image data, one-dimensional image data, intensity data, and spectrum data of the protective film.

[0013] <4> In the above <1> to <3> In any one of the laser processing methods, at least a portion of the data related to the protective film acquired in the protective film detection step may be used in at least one of the outer shape measurement step, the rough alignment step, and the fine alignment step.

[0014] <5> A laser processing device according to one aspect of the present invention includes: a protective film detection unit for measuring a protective film coated on a workpiece to obtain data related to the protective film, wherein the workpiece is arranged on a processing table; a positioning unit for determining the position of the workpiece; and a processing unit for laser processing a processing line of the workpiece, wherein the positioning unit uses the data related to the protective film obtained by the protective film detection unit in at least a part of the detection of the position of the workpiece.

[0015] <6> In the above <5> In the laser processing device, the positioning unit may include an alignment microscope.

[0016] According to the present invention, the throughput of laser ablation processing of a workpiece can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram showing a laser processing apparatus according to an embodiment of the present invention.

[0018] Figure 2 Schematic diagram showing a protective film detection unit in this embodiment.

[0019] Figure 3 This is a plan view showing an example of an image of a wafer acquired by the protective film detection unit in this embodiment.

[0020] Figure 4 This is a schematic diagram for explaining an example of inspecting a protective film using ultraviolet light irradiated from an irradiation unit in this embodiment.

[0021] Figure 5 It is a plan view illustrating an example of performing wafer outer shape measurement and rough alignment based on image data acquired by the protective film detection unit in this embodiment.

[0022] Figure 6 It is a plan view illustrating an example in which fine alignment of a wafer is performed based on image data acquired by a protective film detection unit according to an embodiment of the present invention.

[0023] Figure 7 This is a flowchart illustrating the laser processing method according to the embodiment.

[0024] Figure 8 This is a flowchart illustrating a laser processing method according to a modified example of the embodiment. DETAILED DESCRIPTION

[0025] The following describes a laser processing method and laser processing apparatus according to an embodiment of the present invention with reference to the accompanying drawings. In the following embodiments, references to the number, value, amount, range, etc. of components are not limited to a specific number, and may be greater than or less than the specific number, unless otherwise specified or clearly limited in principle.

[0026] Furthermore, when referring to the shape or positional relationship of components, etc., except for cases where it is specifically stated or cases where it is obvious that this is not the case in principle, shapes similar to or similar to the shape are substantially included.

[0027] In addition, the drawings may be exaggerated to facilitate understanding of features, such as by enlarging features, and the dimensional ratios of components may not necessarily be the same as in reality. In addition, to facilitate understanding of the cross-sectional structure of components, hatching of some components may be omitted in cross-sectional views.

[0028] <Laser processing equipment>

[0029] Figure 1 It is a schematic diagram showing a laser processing apparatus according to one embodiment of the present invention. Figure 2 This is a schematic diagram illustrating a protective film detection unit. The laser processing apparatus 1 is, for example, an apparatus that cuts processing lines (cutting streets) in a workpiece W using laser ablation (laser processing). In this embodiment, the workpiece W is described as a "wafer W." A device layer DL (semiconductor circuit pattern) is formed on the surface of a wafer body Wb of the wafer W. It should be noted that the workpiece W is not limited to a wafer.

[0030] like Figure 1 As shown in FIG. 1 , the laser processing apparatus 1 includes a protective film detection unit 2, a positioning unit 3, a control unit 4, and a processing unit 5. The laser processing apparatus 1 performs protective film detection, positioning, and processing on a wafer W on a processing table 11. Figure 1 As shown, the protective film detection unit 2 , the positioning unit 3 , and the processing unit 5 are arranged above the processing table 11 .

[0031] [Protective Film Inspection Department]

[0032] In the protective film detection unit 2, as shown in FIG. Figure 2 As shown in FIG. 1 , for example, a wafer W having a protective film Pf coated on the entire surface (ie, the device layer DL) is placed on a processing table 11. Figure 2As shown, the protective film detection unit 2 includes a light source 21, a detector 22, condenser lenses 24 and 29, color filters 25 and 28, and a dichroic mirror 26. The protective film detection unit 2 guides ultraviolet light 23 emitted from the light source 21 to the wafer W via the condenser lens 24, the color filter 25, and the dichroic mirror 26. The protective film detection unit 2 measures the protective film Pf by guiding reflected light 27 reflected by the wafer W via the dichroic mirror 26, the color filter 28, and the condenser lens 29 to the detector 22.

[0033] Figure 3 This is a plan view showing an example of image data of a wafer acquired by the protective film detection unit in this embodiment.

[0034] like Figure 2 and Figure 3 As shown, the protective film detection unit 2 obtains image data 30 for inspection based on the measured protective film Pf when the wafer W is placed on the processing table 11. Regarding the image data 30, a two-dimensional image of the entire wafer W (that is, the entire protective film Pf) associated with the absolute position coordinates of the processing table 11 is obtained with high resolution. The protective film detection unit 2 sends a signal to the control unit 4 (see Figure 1 ) sends the acquired image data 30. The image data 30 acquired by the protective film detection unit 2 may be image data of the entire wafer W or image data of a portion of the wafer W.

[0035] Examples of detector 22 in protective film inspection unit 2 include an area sensor camera, a line sensor camera, a photomultiplier tube, and a spectrometer. The area sensor camera captures two-dimensional image data of the entire wafer W (the entire protective film). This two-dimensional image data can be used as image data 30 for inspecting protective film Pf.

[0036] The linear sensor camera captures one-dimensional image data of the entire wafer W (the entire protective film Pf). The one-dimensional image data captured by the linear sensor camera is associated with positional information. Therefore, by synthesizing multiple one-dimensional image data and converting them into two-dimensional image data based on the positional information, this data can be used as image data 30 for inspecting the protective film Pf.

[0037] The photomultiplier tube acquires intensity data for the entire wafer W (the entire protective film Pf). The intensity data acquired by the photomultiplier tube is associated with positional information. Therefore, by synthesizing multiple intensity data and converting them into two-dimensional image data based on the positional information, this data can be used as image data 30 for inspecting the protective film Pf.

[0038] The spectrometer acquires spectral data for the entire wafer (the entire protective film Pf). The spectral data acquired by the spectrometer is associated with positional information. Therefore, by synthesizing multiple spectral data and converting them into two-dimensional image data based on the positional information, this data can be used as image data 30 for inspecting the protective film Pf.

[0039] Figure 4 This is a schematic diagram for explaining an example of inspecting a protective film using ultraviolet light irradiated from an irradiation unit in this embodiment.

[0040] like Figure 4 As shown, when the ultraviolet light 23 reaches the surface of the wafer W, the ultraviolet light 23 is reflected by the surface of the wafer W. On the other hand, when the ultraviolet light 23 reaches the protective film Pf, the additive included in the protective film Pf generates fluorescence 23A due to the ultraviolet light 23. The ultraviolet light reflected from the wafer W and the fluorescence 23A emitted from the protective film Pf are included in the image data 30 (refer to FIG. Figure 3 )middle.

[0041] The protective film inspection unit 2 inspects the protective film Pf for coating defects, coating residue, and abnormal film thickness based on the acquired image data 30 of the entire wafer W. In this embodiment, an example of inspecting the protective film Pf based on the fluorescence 23A generated by the protective film Pf is described, but the protective film may also be inspected using other inspection methods.

[0042] The protective film detection unit 2 sends a signal to the control unit 4 (see Figure 1 ) sends the acquired image data 30 and inspection results of the entire wafer W. If the protective film Pf does not have poor coating, coating residue, or abnormal film thickness and is properly coated with the protective film Pf, the control unit 4 sends the positioning unit 3 (refer to Figure 1 ) sends image data 30 of the entire wafer W.

[0043] The protective film detection unit 2 can also acquire positional information and intensity information of the protective film Pf, rather than being limited to acquiring image data 30. For example, the protective film detection unit 2 can also acquire at least one of two-dimensional image data, one-dimensional image data, intensity data, and spectral data of the protective film Pf. Therefore, the data related to the protective film can include either positional information or intensity information, and more specifically, can include at least one of two-dimensional image data, one-dimensional image data, intensity data, and spectral data.

[0044] [Positioning Department]

[0045] Figure 5 It is a plan view illustrating an example of performing wafer outer shape measurement and rough alignment based on image data acquired by a protective film detection unit.

[0046] like Figure 1 and Figure 5 As shown, in the protective film Pf (refer to Figure 2 ) When there is no coating defect or coating residue and abnormal film thickness, the positioning unit 3 performs shape measurement (SRS) to obtain the center position O1 and size (shape) of the wafer W based on the image data 30 of the entire wafer W. During positioning, the image data of the entire wafer W can be used, or only a part of the image data of the entire wafer W can be used. Therefore, when there is no need to distinguish, the image data 30 refers to the image data of the entire wafer W and the image data of a part of the wafer W. Specifically, the positioning unit 3 detects three points 32 to 34 on the outer periphery (edge) 31 in the image data 30, and obtains the shape 9 (i.e., size) of the wafer W and the center position O1 of the wafer W based on the detected three points 32 to 34. It should be noted that for confirmation, a point 35 on the outer periphery 31 can be detected. At this time, when the wafer W is set on the processing table 11, the center position O1 of the wafer W and the center position O2 of the processing table 11 (refer to Figure 2 ) are roughly consistent.

[0047] Next, the positioning unit 3 performs the alignment according to the dicing streets (processing lines) 37 and the alignment pattern 38 (see FIG. 3 ) of the wafer W based on the image data 30 . Figure 3 ) determines the rough alignment of the θ position and the Y position. The alignment pattern 38 is part of the layout of the wafer loaded with devices. That is, the positioning unit 3 detects the scribe lines 37 and the alignment pattern 38 based on the registered pattern for rough alignment in the image data 30. Based on the detected scribe lines 37 and alignment pattern 38, the positioning unit 3 determines the θ position based on the center position O1 of the wafer W and the Y position of the wafer W in the Y direction. The θ position and the Y position are determined, for example, by detecting the scribe lines 37 and the alignment pattern 38. The θ position and the Y position of the wafer W are roughly determined by the rough alignment.

[0048] Figure 6 This is a plan view showing an example of performing fine alignment of a wafer based on image data acquired by a protective film detection unit.

[0049] After the wafer W is roughly aligned to the approximate position, the positioning unit 3 performs fine alignment based on the image data 30. That is, the positioning unit 3 detects the alignment pattern 38 formed on the wafer W based on the image data 30 and precisely positions the wafer W. The alignment pattern 38 detected in the fine alignment is a finer pattern than the alignment pattern 38 detected in the coarse alignment. The positioning unit 3 detects the processing line 37 of the wafer W for each processing axis by performing fine alignment. In detail, the positioning unit 3 detects the configuration of the alignment pattern 38 on the wafer W based on the registered pattern 39 for detecting the alignment pattern 38 in the image data 30 and precisely positions the wafer W. The positioning unit 3 detects the processing line 37 of the wafer W by performing fine alignment. For example, Figure 6The registered pattern 39 in FIG. 1 is a pattern for detecting the processing line 37 extending in the X direction. Another registered pattern may be used to detect the processing line 37 extending in the Y direction. The position of the wafer W is determined by the above method.

[0050] The reason for dividing alignment into coarse alignment and fine alignment is as follows. Specifically, if only fine alignment is performed and the placement of the alignment pattern 38 is detected from the outset based on a model of the registered pattern 39, high-precision detection is required, which takes time. Therefore, prior to fine alignment, the wafer W is roughly positioned using coarse alignment. After coarse alignment has roughly positioned the wafer W, fine alignment detects the roughly positioned alignment pattern 38 based on the registered pattern 39. This allows for quick detection of the alignment pattern 38. Consequently, during fine alignment, the wafer W can be precisely aligned in a short period of time.

[0051] The positioning unit 3 may use position information and intensity information in at least a portion of position detection of the wafer W (e.g., at least one of a shape measurement process, a rough alignment process, and a fine alignment process). Specifically, two-dimensional image data, one-dimensional image data, intensity data, or spectral data may be used.

[0052] [Control Department]

[0053] After the positioning unit 3 detects the processing line 37 of the wafer W for each processing axis by fine alignment, the control unit 4 operates the processing unit 5. The processing unit 5 makes the processing table 11 (see Figure 2 ) is moved in the Y direction. By moving the processing table 11 in the Y direction, the wafer W is aligned with the laser irradiation portion (not shown) of the processing unit 5 in the Y-axis direction.

[0054] [Processing Department]

[0055] The processing unit 5 aligns the wafer W in the Y-axis direction, moves the wafer W in the X-axis direction, and emits a laser beam from a laser irradiation unit of the processing unit 5. The emitted laser beam is focused and irradiated onto the processing line 37, thereby cutting the processing line 37 by laser ablation.

[0056] <Laser processing method>

[0057] Then, based on Figure 1 and Figure 7 A laser processing method for performing laser ablation processing on a wafer W using the laser processing apparatus 1 will be described.

[0058] Figure 7 is a flow chart illustrating the laser processing method.

[0059] like Figures 1 to 3 and Figure 7 As shown, in step S10, the protective film detection unit 2 acquires image data 30 of the entire wafer W (ie, the entire protective film Pf) (protective film detection step). The image data 30 is compared with the processing table 11 (see Figure 4 After acquiring the image data 30, in step S11, the protective film detection unit 2 detects the protective film Pf (see FIG. 1 ) based on the image data 30. Figure 2 ) Check whether there is poor coating, coating residue, or abnormal film thickness.

[0060] In step S12, it is determined whether the protective film Pf has poor coating, coating residue, or abnormal film thickness. If the protective film Pf has poor coating, coating residue, or abnormal film thickness, in other words, if the quality of the protective film is poor, for example, the protective film Pf is re-coated on the wafer W (step S17). On the other hand, in step S12, if the protective film Pf has not poor coating, coating residue, or abnormal film thickness, and has been properly coated, in other words, if the quality of the protective film is good, the process proceeds to step S13.

[0061] like Figure 1 、 Figure 5 and Figure 7 As shown, in step S13, the positioning unit 3 performs shape measurement (SRS) to detect the center position O1 and dimensions (shape) of the wafer based on the image data 30 acquired by the protective film detection unit 2. Specifically, three points 32 to 34 on the outer periphery 31 are detected in the image data 30, and the outer shape (i.e., dimensions) of the wafer W and the center position O1 of the wafer W are detected based on the detected three points 32 to 34 (positioning process).

[0062] After the wafer's outer shape is measured, the positioning unit 3 performs coarse alignment in step S14. Specifically, the scribe lines 37 and alignment patterns 38 are detected based on the image data 30. Based on the detected scribe lines 37 and alignment patterns 38, the θ position and the Y position of the wafer in the Y direction are determined relative to the center position O1 of the wafer W. This coarse alignment allows the wafer W to be roughly positioned (positioning step).

[0063] After the wafer W is roughly positioned by rough alignment, fine alignment is performed by the positioning unit 3 in step S15. Specifically, fine alignment is performed based on the image data 30 to detect the processing line 37 of the wafer W for each processing axis and precisely position the wafer W (positioning step).

[0064] After fine alignment is performed to detect the processing line 37 of the wafer W, the processing unit 5 is operated to move the processing table 11 in the Y-axis direction. By moving the processing table 11 in the Y-axis direction, the wafer W is aligned with the laser irradiation unit (not shown) of the processing unit 5 in the Y-axis direction.

[0065] After the wafer W is aligned in the Y-axis direction, in step S16, the wafer W is moved in the X-axis direction, and a laser beam is emitted from the laser irradiation unit of the processing unit 5. The emitted laser beam is focused and irradiated onto the processing line 37, thereby cutting the processing line 37 by laser ablation (processing step).

[0066] In the laser processing method according to this embodiment, the protective film detection unit 2 acquires image data 30, and the wafer W is subjected to external shape measurement, coarse alignment, and fine alignment based on the acquired image data 30. Specifically, the positioning process includes an external shape measurement process, a coarse alignment process, and a fine alignment process, and image data is used in these processes.

[0067] According to the laser processing method and laser processing device 1 described above, Figures 1 to 3 As shown, the protective film detection unit 2 performs a protective film detection step, thereby acquiring image data 30 of the wafer W placed on the processing table 11. Based on the acquired image data 30, the processing line 37 of the wafer W is detected. Specifically, the image data 30 is used when detecting the processing line 37 based on the outer shape measurement, rough alignment, and fine alignment of the wafer W during the positioning step performed by the positioning unit 3. Therefore, when detecting the processing line 37 of the wafer W, measurement using an alignment microscope (low-magnification microscope and high-magnification microscope) can be omitted, thereby enabling rapid detection of the processing line 37.

[0068] Here, processing line 37 of wafer W is detected while it is installed on processing table 11. Processing table 11 is a table used when laser ablation processing is being performed on wafer W. Therefore, while laser ablation processing is being performed on wafer W, processing lines of other wafers cannot be detected on processing table 11. Therefore, rapid detection of processing line 37 is directly related to improving the overall processing throughput of wafers W. Therefore, by using image data 30 when detecting processing line 37, throughput during laser ablation processing of wafers W can be improved.

[0069] Furthermore, while the embodiment describes an example in which the image data 30 is used to perform shape measurement, rough alignment, and fine alignment during inspection of the processing line 37, the present invention is not limited thereto. As another example, during inspection of the processing line 37, the image data 30 may be used for at least a portion of the shape measurement, rough alignment, and fine alignment. Modifications are described in detail below.

[0070] <Modification>

[0071] Next, a modification of the embodiment will be described. Note that in the modification, the same reference numerals and step numbers are used for the same or similar contents as those in the embodiment, and detailed descriptions thereof will be omitted.

[0072] like Figure 1 As shown, a laser processing apparatus 50 according to a modified example includes a positioning unit 51. The positioning unit 51 includes an alignment microscope (not shown). The alignment microscope includes a low-magnification microscope and a high-magnification microscope (both not shown).

[0073] The low-magnification microscope observes the device layer DL to detect the shape of the wafer W and the processing line 37 (both refer to Figure 3 The high-magnification microscope measures (observes) the protective film Pf to detect the processing line 37 and the alignment pattern 38 of the wafer W when performing fine alignment.

[0074] The positioning unit 51 performs outer shape measurement and rough alignment based on the wafer W and the protective film Pf measured by a low-magnification microscope, and performs fine alignment based on the wafer W and the protective film Pf measured by a high-magnification microscope.

[0075] Next, based on Figure 1 and Figure 8 , a laser processing method for performing laser ablation processing on a wafer W using the laser processing apparatus 50 according to a modified example will be described.

[0076] Figure 8 This is a flowchart illustrating a laser processing method in a modified example.

[0077] like Figure 1 、 Figure 2 and Figure 8 As shown, in step S12, if the protective film Pf is properly coated without any coating defects, coating residue, or abnormal film thickness, the process proceeds to step S20. In step S20, a determination is made as to whether image data 30 acquired by the protective film detection unit 2 is to be used for external shape measurement. If the determination is to use image data 30, the process proceeds to step S13. On the other hand, if the determination is not to use image data 30 in step S20, the wafer W is measured using a low-magnification microscope in step S21. After the wafer W is measured using the low-magnification microscope, external shape measurement is performed based on the low-magnification microscope image in step S13.

[0078] After performing the outer shape measurement, in step S22, it is determined whether the image data 30 acquired by the protective film detection unit 2 is to be used in the rough alignment. If it is determined that the image data 30 is to be used, the process proceeds to step S14. On the other hand, if it is determined in step S22 that the image data 30 is not to be used, in step S23, the wafer W is measured using a low-magnification microscope. After the wafer W is measured using the low-magnification microscope, in step S14, rough alignment is performed based on the image measured using the low-magnification microscope. The rough alignment allows the wafer W to be roughly positioned.

[0079] After coarse alignment is performed, in step S24, it is determined whether the image data 30 acquired by the protective film detection unit 2 is used in fine alignment. If it is determined that the image data 30 is used, the process proceeds to step S15. On the other hand, if it is determined in step S24 that the image data 30 is not used, in step S25, the wafer W is measured using a high-magnification microscope. After the wafer W is measured using the high-magnification microscope, in step S15, fine alignment is performed based on the measured image using the high-magnification microscope. By performing fine alignment, the processing line 37 of the wafer W is detected for each processing axis and the wafer W is precisely positioned. After the processing line 37 of the wafer W is detected through fine alignment, in step S16, the processing unit 5 cuts the processing line 37 by laser ablation.

[0080] According to the laser processing method and laser processing apparatus 50 of the modified example described above, the positioning unit 51 includes a low-magnification microscope and a high-magnification microscope as alignment microscopes. Therefore, for example, when the protective film Pf is not properly applied to the wafer W, or when manually inspecting the processing line 37 (see Figure 3 ), an alignment microscope can be used to detect the processing line 37.

[0081] In addition, the technical scope of the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the spirit of the present invention.

[0082] For example, in the above embodiment, the protective film detection unit 2 adopts Figure 2 The case of the structure shown (coaxial epi-illumination) is described, but annular illumination or other illumination may be used instead of coaxial epi-illumination. For example, when annular illumination is used, a focusing lens may be coaxially arranged in the central space of the annular illumination that emits ultraviolet light, and the fluorescence emitted after receiving the ultraviolet light irradiated from the annular illumination is received by a detector, wherein the detector is arranged to be opposite to the protective film across the focusing lens. Alternatively, the ultraviolet light may be obliquely irradiated to the protective film, and the light reflected by the protective film may be received at a regular reflection position by a combination of a focusing lens and a detector. In this case, it may also be considered to receive light by a combination of a focusing lens and a detector that are arranged perpendicularly and oppositely to the irradiation position of the ultraviolet light instead of receiving regular reflection light.

[0083] In addition, in the modification, an example is described in which the alignment microscope includes a low-magnification microscope and a high-magnification microscope. However, for example, the alignment microscope may include either a low-magnification microscope or a high-magnification microscope. In addition, a microscope with variable magnification may be used as both the low-magnification microscope and the high-magnification microscope.

[0084] Furthermore, the structural elements in this embodiment may be appropriately replaced with well-known structural elements without departing from the scope of the present invention.

[0085] Description of Reference Numerals

[0086] 1 Laser processing equipment

[0087] 2 Protective film inspection department

[0088] 3 Positioning part

[0089] 4 Control Unit

[0090] 5 Processing Department

[0091] 11 Processing table

[0092] 21 Light Source

[0093] 22 detectors

[0094] 23 Ultraviolet light

[0095] 23A fluorescence

[0096] 24 Condenser lens

[0097] 25 Color Filters

[0098] 26 Dichroic Mirror

[0099] 27 Reflected Light

[0100] 28 Color Filters

[0101] 29 Condenser lens

[0102] 30 Image Data

[0103] 31 outer periphery (edge)

[0104] 37 cutting lanes (processing lines)

[0105] 38, 39 patterns

[0106] 50 Laser processing equipment

[0107] 51 Positioning unit

Claims

1. A laser processing method comprising: a protective film detection step of measuring the protective film coated on the workpiece to obtain data related to the protective film, wherein the workpiece is placed on a processing table; Positioning process, determining the position of the workpiece; and Processing step, laser processing is performed on the processing line of the workpiece, In the positioning step, the data on the protective film acquired in the protective film detection step is used in at least a part of the detection of the position of the workpiece.

2. The laser processing method according to claim 1, wherein: The positioning process includes a shape measuring process, a rough alignment process, and a fine alignment process, and data related to the protective film is used in at least one of the shape measuring process, the rough alignment process, and the fine alignment process.

3. The laser processing method according to claim 1 or 2, wherein: The data related to the protective film includes at least one of two-dimensional image data, one-dimensional image data, intensity data, and spectrum data of the protective film.

4. The laser processing method according to claim 1 or 2, wherein: At least a portion of the data related to the protective film acquired in the protective film detection step is used in at least a portion of the workpiece position detection.

5. A laser processing device comprising: a protective film detection unit for measuring a protective film coated on a workpiece to obtain data related to the protective film, wherein the workpiece is placed on a processing table; A positioning portion, used to determine the position of the workpiece; and A processing unit, used for laser processing the processing line of the workpiece, The positioning unit uses data related to the protective film acquired by the protective film detection unit in at least a part of detection of the position of the workpiece.

6. The laser processing device according to claim 5, wherein: The positioning portion includes an alignment microscope.

Images