LASER PROCESSING DEVICE, MICROSCOPE DEVICE AND LASER PROCESS

Abstract

A laser processing device comprises an arrangement unit on which a sample is arranged; a laser output unit for emitting laser light; a laser irradiation unit for irradiating the sample arranged on the arrangement unit with the laser light emitted by the laser output unit; and a transparent element that is arranged on an optical axis of the laser light between the sample arranged on the arrangement unit and the laser irradiation unit and that transmits the laser light.The laser irradiation unit comprises a spatial light modulator that displays a modulation pattern and generates a first laser light and a second laser light from the laser light by modulating the laser light according to the modulation pattern, and emits the first laser light and the second laser light, a focusing unit for forming a first focal point by focusing the first laser light and for forming a second focal point by focusing the second laser light, and a control unit for controlling the spatial light modulator.

Description

Technical field

[0001] The present disclosure relates to a laser processing device, a microscope device and a laser processing method. State of the art

[0002] Patent literature 1 describes a laser processing method. In this method, a workpiece is held in a vacuum chamber. The vacuum chamber is provided with a window that allows a laser beam to pass through. Additionally, a laser beam emitted from a laser light source is transmitted through the window and directed onto the workpiece. Consequently, an etching phenomenon known as ablation occurs on the surface of the workpiece, and the surface of the workpiece is removed. List of citations, patent literature

[0003] Patent literature 1: Japanese unexamined patent publication no. JP 2002-248589 A Summary of the invention; Technical task

[0004] There is a need to perform ablation on a sample by irradiating the sample with laser light through a transparent element, such as the window of a vacuum chamber, as described in the laser processing method described in patent reference 1. When ablation is performed on the sample, particles can be generated from the sample that may adhere to the transparent element. If the ablation continues while the particles are adhering to the transparent element, its transmittance to the laser light decreases, thereby reducing the processing quality or causing unintended absorption of the laser light by the transparent element, which can damage the transparent element and poses a risk.

[0005] The purpose of the present disclosure is to provide a laser processing device, a microscope device and a laser processing method with which a reduction in the transmittance of a transparent element can be suppressed. Solution to the problem

[0006] A laser processing device according to the present disclosure is [1] “a laser processing device comprising: an arrangement unit on which a sample is arranged; a laser output unit configured to emit laser light; a laser irradiation unit configured to irradiate the sample arranged on the arrangement unit with the laser light emitted by the laser output unit; and a transparent element arranged on an optical axis of the laser light between the sample arranged on the arrangement unit and the laser irradiation unit, which transmits the laser light.”The laser irradiation unit comprises a spatial light modulator configured to display a modulation pattern and to generate a first laser light and a second laser light from the laser light by modulating the laser light according to the modulation pattern, and to emit the first laser light and the second laser light, a focusing unit configured to form a first focal point by focusing the first laser light, and configured to form a second focal point by focusing the second laser light, and a control unit configured to control the spatial light modulator.The control unit instructs the spatial light modulator to display the modulation pattern generated based on the focal length of the focusing unit, such that by instructing the focusing unit to focus the first laser light and the second laser light emitted by the spatial light modulator, the first focal point is positioned at a first position on the sample side with respect to the transparent element, the second focal point is located at a second position on the side of the transparent element with respect to the first focal point, and a distance between the first focal point and the second focal point in an optical axis direction of the first laser light and the second laser light is set to a specified distance.The laser irradiation unit simultaneously performs ablation processing of the sample using the first laser light and ablation processing of particles generated by the ablation processing of the sample using the second laser light.

[0007] A laser processing method according to the present disclosure is

[13] “a laser processing method using a laser processing device comprising an arrangement unit on which a sample is arranged, a laser output unit for emitting laser light, a laser irradiation unit for irradiating the sample arranged on the arrangement unit with the laser light emitted by the laser output unit, and a transmissive element arranged on an optical axis of the laser light between the sample arranged on the arrangement unit and the laser irradiation unit, and which transmits the laser light, wherein the laser processing method comprises: a processing step for performing an ablation process using a first laser light and a second laser light generated from the laser light. The laser irradiation unit comprises a spatial light modulator,The spatial light modulator displays a modulation pattern and generates the first and second laser lights from the laser light by modulating the laser light according to the modulation pattern, and emits the first and second laser lights; a focusing unit for forming a first focal point by focusing the first laser light and for forming a second focal point by focusing the second laser light; and a control unit for controlling the spatial light modulator. The processing step includes a first step in which the spatial light modulator is caused to display the modulation pattern generated based on a focal length of the focusing unit, such that by causing the focusing unit to focus the first and second laser lights emitted by the spatial light modulator, the first focal point is positioned at a first position on the sample side with respect to the transparent element.the second focal point is located at a second position on the side of the transparent element with respect to the first focal point, and the distance between the first focal point and the second focal point in an optical axis direction of the first laser light and the second laser light is set to a fixed distance, and a second step in which an ablation treatment of the sample is carried out simultaneously using the first laser light and an ablation treatment of particles generated by the ablation treatment of the sample is carried out using the second laser light after the first step.

[0008] In the laser processing device and laser processing method, the spatial light modulator generates the first and second laser lights by modulating the laser light output by the laser output unit according to the modulation pattern. The focusing unit forms the first focal point of the first laser light and the second focal point of the second laser light by focusing the first and second laser lights generated by the spatial light modulator. At this point, the modulation pattern, generated such that the first focal point is located at the first position on the sample side relative to the transparent element and the second focal point is located at the second position on the transparent element side relative to the first focal point, is displayed on the spatial light modulator.Accordingly, the ablation of the sample using the first laser light and the ablation of the particles generated by the sample ablation using the second laser light are performed simultaneously. Therefore, it is possible to suppress a reduction in the transmittance of the transparent element due to the adhesion of the particles generated by the sample ablation, while simultaneously shortening the processing time.

[0009] Here, the distance between the sample and the transparent element can change depending on the sample size, the shape and size of the transparent element, or similar factors. Therefore, to effectively and simultaneously perform sample ablation using the first laser light and particle ablation using the second laser light, it is desirable to set the distance between the first focal point of the first laser light and the second focal point of the second laser light to a suitable distance. In contrast, in the laser processing device and laser processing method, the modulation pattern generated based on the focal length of the focusing unit is displayed on the spatial light modulator, such that the distance between the first and second focal points in the optical axis direction of the first and second laser lights assumes a desired set distance.Therefore, the distance between the first focal point of the first laser light and the second focal point of the second laser light can be adjusted to a suitable distance, and the ablation of the sample using the first laser light and the ablation of the particles using the second laser light can be carried out effectively and simultaneously. As described above, according to the laser processing device and laser processing method, it is possible to effectively suppress a reduction in the transmittance of the transparent element while simultaneously shortening the processing time.

[0010] Incidentally, it is specified in [1] and

[13] above that the transparent element is arranged on the optical axis of the laser light between the sample mounted on the assembly unit and the laser irradiation unit. Meanwhile, the spatial light modulator of the laser irradiation unit generates the first laser light and the second laser light from the laser light. Therefore, the transparent element is specifically arranged on the optical axis of the first laser light and the second laser light as laser light between the sample mounted on the assembly unit and the laser irradiation unit.

[0011] A laser processing device according to the present disclosure can [2] “be the laser processing device according to [1] in which the spatial light modulator displays the modulation pattern comprising a lens pattern that focuses only a portion of the laser light, and generates the second laser light comprising that portion of the laser light, and the first laser light comprising the remainder of the laser light, by modulating the laser light according to the modulation pattern. The control unit causes the spatial light modulator to display the modulation pattern comprising the lens pattern with a focal length calculated on the basis of the focal length of the focusing unit and the set distance, such that the distance between the first focal point and the second focal point becomes the set distance.”In this case, by using the modulation pattern that contains the lens pattern which focuses only a portion of the laser light, it is possible to adjust the distance between the first focal point and the second focal point to a desired set distance in a suitable manner while generating the first laser light and the second laser light.

[0012] A laser processing device according to the present disclosure can [3] “be the laser processing device according to [1] or [2] above, wherein the control unit causes the spatial light modulator to display the generated modulation pattern such that the ratio between an intensity of the first laser light at the first focal point and an intensity of the second laser light at the second focal point becomes a set ratio.” In this case, the ratio between the intensity of the first laser light at the first focal point and the intensity of the second laser light at the second focal point can be set to a desired ratio suitable for each processing operation.

[0013] A laser processing device according to the present disclosure can [4] be “the laser processing device according to any of the above [1] to [3], wherein the control unit causes the spatial light modulator to display the modulation pattern generated on the basis of the irradiation conditions of the first laser light and the irradiation conditions of the second laser light”. In this case, the irradiation conditions of the first laser light and the irradiation conditions of the second laser light can be set to desired conditions.

[0014] A laser processing device according to the present disclosure can [5] “be the laser processing device according to [4] above, wherein the irradiation conditions of the second laser light include a condition under which a beam pattern of the second laser light assumes a top-hat shape at the second focal point”. In this case, the ablation of the particles generated by the ablation of the sample can be carried out efficiently using the second laser light.

[0015] A laser processing device according to the present disclosure can [6] “be the laser processing device according to [4] wherein the irradiation conditions of the second laser light include a condition under which several second focal points are formed along the optical axis direction of the second laser light”. In this case, the ablation of the particles resulting from the ablation of the sample can be carried out using the second laser light over a larger area in the optical axis direction of the second laser light. Therefore, for example, even if the second focal point is shifted in the optical axis direction or if the processing position (for example, a position on the surface of the transparent element) is shifted in the optical axis direction due to environmental changes, temporal changes, or the like, stable ablation processing can be carried out.

[0016] A laser processing device according to the present disclosure can be [7] “the laser processing device according to any of the above [4] to [6], wherein the irradiation conditions of the first laser light include a condition in which a plurality of first focal points are formed along a direction that intersects the optical axis direction of the first laser light.” In this case, the ablation processing of the sample can be carried out efficiently. Furthermore, in this case, for example, by adjusting the polarization direction of the first laser light at the multiple first focal points arranged along the direction that intersects the optical axis direction of the first laser light (for example, by adjusting the polarization directions so that they are orthogonal to each other between adjacent first focal points), the formation of a fine periodic structure on the processed cross-section of the sample can be suppressed.

[0017] A laser processing device according to the present disclosure can be [8] “the laser processing device according to any one of points [1] to [7] above, wherein the laser irradiation unit comprises a variable attenuator configured to set a power of the laser light”. In this case, the output (processing point output) of the first laser light at the first focal point P1 can be set to a desired value.

[0018] A laser processing device according to the present disclosure can [9] “be the laser processing device according to any of the above [1] to [8], wherein the laser irradiation unit includes a half-wave plate arranged in front of the spatial light modulator and controlling the polarization direction of the laser light incident on the spatial light modulator”. In this case, the ratio between modulated light, which is part of the laser light modulated by the spatial light modulator, and unmodulated light, which is part of the laser light not modulated by the spatial light modulator, can be adjusted.

[0019] A laser processing device according to the present disclosure can be

[10] “the laser processing device according to any of the above [1] to [9], wherein the pulse width of the laser light is 1 ps or less”. In this case, ablation processing can be carried out effectively. Furthermore, in this case, changes in the properties of the processed cross-section due to heat can be suppressed by using an ultrashort pulse laser with a pulse width of 1 ps or less.

[0020] A laser processing device according to the present disclosure can

[11] “the laser processing device according to any of the above points [1] to

[10] further comprises a distance measuring unit configured to measure a distance between the sample and the transparent element by detecting light reflected from a laser light incident surface of the sample and light reflected from a surface on the sample side of the transparent element. The control unit determines the set distance based on the distance measured by the distance measuring unit.” In this case, the distance between the first focal point and the second focal point can be set to a desired set distance based on the measurement result of the distance measuring unit, even if the distance between the sample and the transparent element is unknown.

[0021] A microscope device according to the present disclosure can

[12] “be a microscope device comprising: the laser processing device according to any of the above [1] to

[11] ; and a microscope unit configured to view the sample arranged on the arrangement unit”. In this case, it is possible to provide a microscope device capable of suppressing a reduction in the transmittance of the transparent element. Advantageous effects of the invention

[0022] According to the present disclosure, it is possible to provide the laser processing device, the microscope device and the laser processing method which are capable of suppressing a reduction in the transmittance of the transparent element. Brief description of the drawings Fig. Figure 1 is a schematic view showing part of a microscope device according to the present embodiment. Fig. 2 is a schematic view showing the remaining part of the Fig. Figure 1 shows the microscope device shown. Fig. 3 is a schematic view showing part of a Fig. The laser irradiation unit shown in section 2 is shown. Fig. Figure 4 is a schematic representation showing the relationship between a first focal point and a second focal point. Fig. Figure 5 is a flowchart showing an example of a laser processing method according to the present embodiment. Fig. 6 is a flowchart that shows certain steps of the process in Fig. Step 5 shown is S102. Fig. Figure 7 is a diagram showing the relationship between the gradation value of a Fresnel lens pattern and the intensity of the second laser light at the second focal point. Fig. Figure 8 is a schematic view showing a distance measurement unit according to a modification example. Description of the embodiments

[0023] The following describes, with reference to the drawings, an embodiment of a laser processing device, a microscope device comprising the laser processing device, and a laser processing method according to the present disclosure. Incidentally, identical or corresponding elements in the description of each drawing are designated with the same reference numerals, and duplicate descriptions may be omitted.

[0024] Fig. Figure 1 is a schematic view showing part of a microscope device according to the present embodiment. Fig. 2 is a schematic view showing the remaining part of the Fig. The microscope apparatus shown in Figure 1 is shown. One in the Fig. 1 and Fig. 2 Microscope device 1 shown is, as will be described later, a device comprising a focused ion beam (FIB) device that performs etching on a sample by irradiating the sample with focused ions (for example, Ga ions); a scanning electron microscope (SEM) device that observes the sample by irradiating the sample with an electron beam; and a laser processing device that performs laser processing (here: ablation processing) on ​​the sample by irradiating the sample with laser light and that enables, by means of the SEM device, the observation of a processed cross-section of the sample formed by the processing by the FIB device and / or the laser processing device.

[0025] The microscope apparatus 1 comprises a sample holder (arrangement unit) 2, a beam irradiation unit 3, a first microscope unit 4, a second microscope unit 5, a cover 7 (transparent element), a chamber 10, and a laser processing device 20. A sample A is arranged on the sample holder 2. The sample holder 2 can support the sample A without securing it, as in a case where the sample A is simply placed on it, or it can secure and hold the sample A, for example, by attaching it or the like. Here, the sample holder 2 holds the sample A. The beam irradiation unit 3 serves to irradiate the sample A (hereinafter referred to as "the same") held (arranged) by the sample holder 2 with a focused ion beam. Therefore, the beam irradiation unit 3 can comprise at least one focused ion beam emission device of the FIB apparatus.

[0026] The first microscope unit 4 serves to observe sample A held by sample holder 2. More precisely, the first microscope unit 4 is configured to acquire an image of sample A (observe sample A) by irradiating sample A held by sample holder 2 with an electron beam and detecting secondary electrons or the like generated in sample A. Therefore, the first microscope unit 4 can be at least part of the SEM device, which includes an electron beam emission device and a detection device.

[0027] Similar to the first microscope unit 4, the second microscope unit 5 serves to observe sample A held by the sample holder 2. More precisely, the second microscope unit 5 can acquire information about the crystal structure or the like of sample A (observe sample A) by irradiating sample A held by the sample holder 2 with an electron beam and detecting the electron beam scattered by sample A. That is, as an example, the second microscope unit 5 is part of the SEM apparatus that uses an electron backscatter diffraction (EBSD) technique and can be part of the SEM apparatus that includes at least one electron beam emission device and a detection device. Incidentally, the microscope apparatus 1 can include a transmission electron microscope (TEM) apparatus instead of (or in addition to) the SEM apparatus.In this case, the first microscope unit 4 and the second microscope unit 5 can be at least part of the TEM device.

[0028] The cover 7 is made of a material that transmits the laser light L described below and serves to cover the sample A held by the sample holder 2. Accordingly, the cover 7 can be positioned at a reference position located between the sample holder 2 and the beam irradiation unit 3, the first microscope unit 4, and the second microscope unit 5 in the beam path of the laser light L. Incidentally, the cover 7 is configured to be movable from this reference position, so that the cover 7 is not located between the sample holder 2 and the beam irradiation unit 3, the first microscope unit 4, and the second microscope unit 5.

[0029] Incidentally, the cover 7 can be in the form of a box or a plate. If the cover 7 is box-shaped, it can, for example, be a rectangular box with one open side (example in Fig. 4) or in the form of a box with one open side and a semicircular cross-section (example in Fig. 1) be designed. In this case, the cover 7, when the sample A is located inside the box, can be arranged such that an open section of the box faces the bottom of the chamber 10 and a bottom of the box faces the side on which the radiation device 3, the first microscope unit 4, and the second microscope unit 5 are located. At this point, an edge region of the box forming the open region can be in contact with or spaced apart from a lower region of the chamber 10.

[0030] Chamber 10 accommodates the sample holder 2, the beam irradiation unit 3, the first microscope unit 4, the second microscope unit 5, and the cover 7. Chamber 10 includes an incidence section 11 for the laser light L, formed as a window made of a material that transmits the laser light L. Furthermore, chamber 10 contains an evacuation section 12 for pressure reduction (creating a vacuum) by evacuating the interior of chamber 10. Additionally, a further unit 6 for processing or observing the sample A held by the sample holder 2 may be provided within chamber 10.

[0031] The laser processing device 20 comprises a laser output unit 30 and a laser irradiation unit 40. The laser output unit 30 serves to output the laser light L with ultrashort pulses at low fluence. The pulse width of the laser light L output by the laser output unit 30 is, for example, 1 ps or less. Furthermore, the fact that the laser light L has a low fluence may indicate, for example, that the energy density of the laser light L is close to a processing threshold of the sample A, which is determined such that ablation is induced during laser processing of the sample A. The laser irradiation unit 40 serves to irradiate the sample A, held by the sample holder 2, with the laser light L output by the laser output unit 30.The laser light L emitted by the laser output unit 30 is guided by the laser irradiation unit 40 and radiated through the entry area 11 into the chamber 10.

[0032] The laser irradiation unit 40 includes a spatial light modulator 41 and a galvanometer scanner 43. The spatial light modulator 41 modulates the laser light output by the laser output unit 30 according to a modulation pattern and emits the modulated laser light. More precisely, the spatial light modulator 41 is, for example, a liquid crystal-on-silicon spatial light modulator (LCOS-SLM) and displays a modulation pattern on a liquid crystal layer, thereby modulating the laser light L incident on and emitted by the liquid crystal layer according to the modulation pattern.

[0033] The spatial light modulator 41 can, for example, as will be described later, suppress the extent of a point system at the focal position of the laser light L by modulating the laser light L such that the laser light L has multiple focal points in an optical axis direction, or by modulating the laser light L to correct aberrations that occur when the laser light passes through the transparent element such as the cover 7 or the incidence section 11.

[0034] The galvanometer scanner 43 contains mirrors 43a and 43b and illuminates the sample A, held by the sample holder 2, with the laser light L emitted by the spatial light modulator 41, while scanning the sample A by controlling the mirrors 43a and 43b. The laser light L emitted by the galvanometer scanner 43 is focused onto the sample A by a lens (focusing unit) 42. The lens 42 is, for example, an fθ lens.

[0035] The laser irradiation unit 40 includes a relay optics system 44. The relay optics system 44 is arranged between the spatial light modulator 41 and the galvanometer scanner 43. The relay optics system 44 contains a pair of lenses 44a and 44b and serves to transmit an image of the laser light L modulated by the spatial light modulator 41 to the lens 42. The beam path of the laser light L emitted by the spatial light modulator 41 and passing through the optical relay system 44 is adjusted by predetermined mirrors 56 and 57, and the laser light L is then directed to the galvanometer scanner 43.

[0036] The laser irradiation unit 40 further comprises a collimator lens 51, an output control unit 52, a beam diameter control unit 53, and a half-wave plate 54, which are arranged sequentially along the beam path of the laser light L from the laser output unit 30 to the spatial light modulator 41. The collimator lens 51 collimates the laser light L emitted by the laser output unit 30 and emits the collimated laser light L. Therefore, the collimated laser light L falls upon the spatial light modulator 41. The collimator lens 51 can be omitted.

[0037] The output control unit 52, for example, is a variable attenuator and adjusts the output of the laser light L emitted by the laser output unit 30. The beam diameter control unit 53, for example, is a beam expander and adjusts the beam diameter of the laser light L emitted by the laser output unit 30. In this way, the output control unit 52 and the beam diameter control unit 53 are arranged between the spatial light modulator 41 and the laser output unit 30 and function as adjustment units that set the power and beam diameter of the laser light L.

[0038] The half-wave plate 54 is arranged in front of the spatial light modulator 41. The half-wave plate 54 changes the polarization direction of the laser light L emitted by the laser output unit 30. As described above, the laser light L incident on the spatial light modulator 41 is modulated and then directed through the galvanometer scanner 43 into the chamber 10, where it is made available for scanning the sample A.

[0039] In the microscope apparatus 1 described above, sample A can be processed using a focused ion beam from the beam irradiation unit 3 or using laser light L from the laser processing device 20. When a focused ion beam is used, sample A can be processed and observed with high accuracy. Conversely, when laser light L is used, a large area of ​​sample A can be processed and observed with high throughput.

[0040] The laser processing device 20 further comprises a control unit 60. The control unit 60 can control at least the spatial light modulator 41, the output control unit 52, and the half-wave plate 54. The control unit 60 is configured as a computer device comprising a processor, memory, storage space, a communication device, and the like. In the control unit 60, the processor performs various processes to control each part, such as the spatial light modulator 41, by executing software (programs) loaded into the memory or the like, and by controlling the reading and writing of data in the memory and storage space, as well as communication via the communication device.

[0041] The functionality of each part of the laser irradiation unit 40 is then described in more detail. Fig. 3 is a schematic view showing part of the Fig. The laser irradiation unit shown in section 2 is shown. As in Fig. As shown in Figure 3, the spatial light modulator 41, under the control of the control unit 60, displays a modulation pattern Q, generates a first laser light L1 and a second laser light L2 from the laser light L by modulating the laser light L according to the modulation pattern Q, and emits the first laser light L1 and the second laser light L2.

[0042] Therefore, the control unit 60 controls the half-wave plate 54 (for example, by adjusting the angle around the optical axis of the laser light L), which is arranged in front of the spatial light modulator 41, in order to convert a polarization direction of the laser light L emitted by the half-wave plate 54 into a polarization direction that gives a first polarization direction, which is the direction of the first linearly polarized light (e.g., p-polarized light) and second linearly polarized light (e.g., s-polarized light) orthogonal to the first polarization direction.

[0043] Furthermore, the control unit 60 controls the spatial light modulator 41 to display the modulation pattern Q, which comprises a Fresnel lens pattern (lens pattern) Qf that focuses only a portion of the laser light L, on the spatial light modulator 41 and generates the second laser light L2, which comprises the portion of the laser light L, and the first laser light L1, which comprises the remainder of the laser light L, by modulating the laser light L according to the modulation pattern Q. The Fresnel lens pattern Qf has a focal length f Q .

[0044] Accordingly, for example, a portion of the laser light component L in the first polarization direction is modulated by the Fresnel lens pattern Qf and emitted by the spatial light modulator 41 as a second laser light L2 while being focused. The remainder of the component in the first polarization direction and the component of the laser light L in a second polarization direction are not modulated by the Fresnel lens pattern Qf and are emitted by the spatial light modulator 41 as the first laser light L1 without focusing. In other words, the second laser light L2 contains a portion (modulated light) of the laser light L that is modulated by the Fresnel lens pattern Qf in the spatial light modulator 41. Furthermore, the first laser light L1 contains the remainder (unmodulated light) of the laser light L.

[0045] The lens 42 forms a first focal point P1 by focusing the first laser light L1 emitted by the spatial light modulator 41, and a second focal point P2 by focusing the second laser light L2 emitted by the spatial light modulator 41. The first focal point P1 is formed on an (original) focal plane Sa, which is spaced from the lens 42 by a focal length f of the lens 42. The second focal point P2 is a position on the side of the spatial light modulator 41 with respect to the first focal point P1 and is formed on a combined focal plane Sb of the Fresnel lens array Qf and the lens 42.

[0046] The distance D12 between the first focal point P1 and the second focal point P2 in an optical axis direction of the first laser light L1 and the second laser light L2 (an offset between the first focal point P1 and the second focal point P2), i.e., the distance between the focal plane Sa and the combined focal plane Sb, is given by the following equation (1) using the focal length f of the lens 42 and a combined focal length f G of the Fresnel lens pattern Qf and the lens 42 expressed. Distance D12=f−fG

[0047] Furthermore, the combined focal length f G by the following equation (2) using the focal length f of lens 42 and the focal length f Q of the Fresnel lens pattern Qf expressed. Combined focal length fG=(f⋅fQ) / (fQ+f)

[0048] Therefore, the distance D12 between the first focal point P1 and the second focal point P2 can be adjusted by setting the focal length f. Q The Fresnel lens pattern Qf can be varied. The control unit 60 sets the distance D12 between the first focal point P1 and the second focal point P2 to a desired target distance by adjusting the Fresnel lens pattern Qf, which is contained in the modulation pattern Q displayed on the spatial light modulator 41. This point is described below.

[0049] Fig. Figure 4 is a schematic representation showing the relationship between the first focal point and the second focal point. As in Fig. 3 and Fig. As shown in Figure 4, the first focal point P1 is located at a first position H1 on the side of sample A with respect to the cover 7, and the second focal point P2 is located at a second position H2 on the side of the cover 7 with respect to the first focal point P1. Accordingly, the first laser light L1 with the first focal point P1 is provided for the ablation of sample A, and the second laser light L2 with the second focal point P2 is provided for the ablation of particles generated from sample A by the ablation of sample A (hereinafter referred to simply as "particles"). The particles generated in sample A include particles suspended between sample A and the cover 7, or particles adhering to a surface 7s on the side of sample A of the cover 7.

[0050] In the example shown, the first position H1 is a position on a surface As on the side of cover 7 of sample A, and the second position H2 is a position on sample side A with respect to surface 7s on sample side A of cover 7. However, the first position H1 can be any position where an ablation operation can be performed on sample A using the first laser light L1 with the first focal point P1 at the first position H1, and can be any position that is at least closer to the side of sample A than to cover 7 (i.e., any position closer to sample A than to cover 7).

[0051] Furthermore, the second position H2 can be any position where ablation treatment can be performed on the particles using the second laser light L2 with the second focal point P2 located at the second position H2, and can be any position that is at least closer to the cover 7 than the first position H1. For example, the second position H2 can be any position outside the cover 7 that is closer to the side of sample A than the surface 7s of the cover 7, as illustrated; a position on the surface 7s of the cover 7; a position inside the cover 7; and a position outside the cover 7 on the side opposite the surface 7s of the cover 7.

[0052] A desired set distance Db between the first focal point P1 and the second focal point P2 is adjusted to the distance at which the ablation of sample A using the first laser light L1 and the ablation of the particles using the second laser light L2 can be performed simultaneously. The set distance Db can be based on a distance Da between the surface As of sample A and the surface 7s of cover 7. The set distance Db can be the same as the distance Da or it can differ from the distance Da (in the illustrated example, it is shorter than the distance Da). The distance D12 between the first focal point P1 and the second focal point P2 is adjusted to the set distance Db.

[0053] To adjust the distance D12 to the set distance Db, the set distance Db and the focal length f of lens 42 are known values, so that, for example, the Fresnel lens pattern Qf with a specific value, which is obtained by substituting the above equation (2) into the combined focal length f Q into the equation, in which the distance D12 in the above equation (1) is set to the set distance Db, and by solving the resulting equation for the focal length f Q The focal length is generated from the Fresnel lens pattern Qf.

[0054] As described above, the control unit 60 causes the spatial light modulator 41 to display the modulation pattern Q (including the Fresnel lens pattern Qf) generated on the basis of the focal length f of the lens 42 such that, by causing the lens 42 to focus the first laser light L1 and the second laser light L2 emitted by the spatial light modulator 41, the first focal point P1 is located at the first position H1 on the sample side A with respect to the cover 7, the second focal point P2 is located at the second position H2 on the side of the cover 7 with respect to the first focal point P1, and the distance D12 between the first focal point P1 and the second focal point P2 in the optical axis direction of the first laser light L1 and the second laser light L2 is set to the set distance Db.

[0055] Accordingly, the laser irradiation unit 40 can simultaneously perform the ablation of sample A using the first laser light L1 and the ablation of particles generated by the ablation of sample A using the second laser light L2.

[0056] The operation of the laser irradiation unit 40 using the laser processing method according to the present embodiment is then described in more detail. Fig. 5 is a flowchart showing an example of the laser processing method according to the present embodiment. As in Fig. As shown in Figure 5, in the laser processing method according to the present embodiment, the irradiation conditions of the laser light L are first determined (step S101).

[0057] Specifically, in step S101, the patterns (irradiation conditions) at the processing points of the first laser light L1 and the second laser light L2 are determined. As an example, with respect to the second laser light L2, a condition is defined under which the beam pattern of the second laser light L2 has a top-hat shape at the second focal point P2, or a condition under which a plurality of second focal points P2 are formed along the optical axis direction of the second laser light L2. As another example, with respect to the first laser light L1, a condition is defined under which a plurality of first focal points P1 are formed along a direction that intersects the optical axis direction of the first laser light L1.

[0058] These irradiation conditions are related to the generation of the modulation pattern Q, which is to be displayed on the spatial light modulator 41 in a later step. For example, to realize the irradiation condition under which the plurality of second focal points P2 are formed along the optical axis direction of the second laser light L2, the modulation pattern Q can be generated such that it contains an axiom lensing pattern. Similarly, to realize the irradiation condition under which the plurality of first focal points P1 are formed along the direction that intersects the optical axis direction of the first laser light L1, the modulation pattern Q can be generated such that it contains a diffraction grating pattern that diffractes and branches the first laser light L1. Therefore, in the next step, the modulation pattern Q to be displayed on the spatial light modulator 41 is determined (step S102: processing step).Step S102 is described in more detail.

[0059] Fig. 6 is a flowchart that shows certain steps of the process in Fig. Step 5, shown in S102, illustrates this. As in Fig. As shown in Figure 6, in step S102, the control unit 60 detects various conditions for generating the modulation pattern Q to be displayed on the spatial light modulator 41. That is, here the control unit 60 first detects the set distance Db (step S201). The set distance Db is determined based on the distance Da between the sample A and the cover 7. If the design value of the distance Da between the sample A and the cover 7 is known, the design value can be used, and if the design value is unknown, the distance Da can be determined by measurement using an optical method (distance measuring unit 70), as described later. The control unit 60 can detect the set distance Db, for example, by accepting an input of the set distance Db determined based on the distance Da.

[0060] Next, the control unit 60 records the focal length f. Qof the Fresnel lens pattern Qf (step S202). As described above, the focal length f can be Q The above equation (1) and equation (2) can be used to calculate the focal length f of lens 42 based on the known set distance Db and the focal length f. The control unit 60 can adjust the focal length f. Q for example by accepting an input of the calculated focal length f Q capture the Fresnel lens pattern Qf.

[0061] Next, the control unit 60 acquires the output value (processing point output) of the first laser light L1 at the first focal point P1 for the ablation processing of sample A (step S203). Furthermore, the control unit 60 acquires the output value (processing point output) of the second laser light L2 at the second focal point P2 for the ablation processing of the particles on the cover side 7 (step S204). The control unit 60 can acquire the output value, for example, by accepting an input of the output value. Incidentally, the processing point power of the second laser light L2 can be a fixed value if the material of the cover 7 is not changed.

[0062] Next, the control unit 60 records the gradation value of the Fresnel lens pattern Qf (phase image) (step S205). The gradation value of the Fresnel lens pattern Qf is determined such that the ratio between the intensity of the first laser light L1 at the first focal point P1 and the intensity of the second laser light L2 at the second focal point P2 becomes a desired target ratio. Fig. Figure 7 is a graph showing the relationship between the gradation value of the Fresnel lens pattern Qf and an intensity J2 of the second laser light L2 at the second focal point P2. Here, a gradation value T, which realizes the intensity J2 of the second laser light L2 at which the ratio between the intensity of the first laser light L1 at the first focal point P1 and the intensity of the second laser light L2 at the second focal point P2 assumes a desired target ratio, is determined based on the [reference to be added]. Fig. The gradation value T is determined as shown in diagram 7 (table). The control unit 60 can, for example, detect the gradation value T by accepting an input of the selected gradation value T.

[0063] Next, the control unit 60 generates the modulation pattern Q based on the various conditions recorded above (step S206: first step). In particular, the control unit 60 determines the Fresnel lens pattern Qf based on the focal length f. Qof the Fresnel lens pattern Qf acquired in step S202 and the gradation value of the Fresnel lens pattern Qf acquired in step S205. In addition, the control unit 60 determines, for example, an axicon lens pattern or a diffraction grating pattern based on the irradiation conditions determined in step S101. Subsequently, the control unit 60 generates the modulation pattern Q in which the Fresnel lens pattern Qf, the axicon lens pattern, the diffraction grating pattern and other patterns (e.g. an aberration correction pattern and the like) are superimposed.

[0064] This means that the control unit 60 generates the modulation pattern Q based on (taking into account) the set distance Db between the first focal point P1 and the second focal point P2 in the optical axis direction of the first laser light L1 and the second laser light L2, the focal length f of the lens 42, the gradation value T of the Fresnel lens pattern Qf, which is set such that the ratio between the intensity of the first laser light L1 at the first focal point P1 and the intensity of the second laser light L2 at the second focal point P2 yields the set ratio, and the irradiation conditions of the first laser light L1 and the second laser light L2.

[0065] The control unit 60 then instructs the spatial light modulator 41 to display the modulation pattern Q generated in step S206 (step S207: first step). Accordingly, in the laser irradiation unit 40, the laser light L is modulated by the modulation pattern Q in the spatial light modulator 41, and the first laser light L1 and the second laser light L2 are generated from the laser light L. Furthermore, the first laser light L1 and the second laser light L2 are focused by the lens 42, and the first focal point P1 and the second focal point P2 are formed simultaneously.At this point, the relationship between the first focal point P1 and the second focal point P2 is established such that, according to the modulation pattern Q (Fresnel lens pattern Qf) and the lens 42, the first focal point P1 is located at the first position H1 on the sample side A with respect to the cover 7, the second focal point P2 is located at the second position H2 on the cover side 7 with respect to the first focal point P1, and the distance between the first focal point P1 and the second focal point P2 in the direction of the optical axis of the first laser light L1 and the second laser light L2 assumes the set distance Db.

[0066] As in Fig. As shown in Figure 5, in the next step, the control unit 60 controls, for example, the output control unit 52, which is a variable attenuator, to adjust the output of the laser light L (step S103). In step S103, the control unit 60 controls the output control unit 52 so that the power of the first laser light L1 at the first focal point P1 becomes the power measured at the processing point in step S203, and the power of the second laser light L2 at the second focal point P2 becomes the power measured at the processing point in step S204.

[0067] Then, for example, in a state where the control unit 60 causes the spatial light modulator 41 to display the modulation pattern Q, the laser output unit 30 to output the laser light L, and the galvanometer scanner 43 to scan the sample A with the first laser light L1 and the second laser light L2, thereby performing ablation processing of the sample A and ablation processing of the particles (step S104: second step). In step S104, the laser irradiation unit 40 simultaneously performs the ablation processing of the sample A using the first laser light L1 and the ablation processing of the particles generated by the ablation processing of the sample A using the second laser light A2.

[0068] In this way, the laser processing method according to the present embodiment comprises the processing step (step S102, steps S201 to S207 and step S104) of performing an ablation process using the first laser light L1 and the second laser light L2, which are generated from the laser light L. Furthermore, the processing step comprises the first step (steps S201 to S207) in which the spatial light modulator 41 is caused to display the modulation pattern Q generated on the basis of the focal length f of the lens 42 such that, by causing the lens 42 to focus the first laser light L1 and the second laser light L2 emitted by the spatial light modulator 41, the first focal point P1 is located at the first position H1 on the side of the sample A with respect to the cover 7.the second focal point P2 is located at the second position H2 on the side of cover 7 with respect to the first focal point P1, and the distance between the first focal point P1 and the second focal point P2 in the optical axis direction of the first laser light L1 and the second laser light L2 is set to the set distance Db, and the second step (step S104) of simultaneously performing an ablation treatment of the sample A using the first laser light L1 and an ablation treatment of the particles generated by the ablation treatment of the sample A using the second laser light L2 is performed after the first step.

[0069] As described above, in the laser processing device 20 and the laser processing method according to the present embodiment, the spatial light modulator 41 generates the first laser light L1 and the second laser light L2 by modulating the laser light L emitted by the laser output unit 30 according to the modulation pattern Q, and the lens 42 forms the first focal point P1 of the first laser light L1 and the second focal point P2 of the second laser light L2 by focusing the first laser light L1 and the second laser light L2 generated by the spatial light modulator 41.

[0070] At this point, the modulation pattern Q, generated such that the first focal point P1 is located at the first position H1 on sample side A relative to the cover 7, and the second focal point P2 is located at the second position H2 on the side of the cover 7 relative to the first focal point P1, is displayed on the spatial light modulator 41. Accordingly, the ablation of sample A using the first laser light L1 and the ablation of the particles generated by the ablation of sample A using the second laser light L2 are performed simultaneously. Therefore, it is possible to suppress a reduction in the transmittance of the cover 7 due to the adhesion of the particles generated by the ablation of sample A, while simultaneously shortening the processing time.

[0071] Here, the distance between sample A and cover 7 can change depending on the size of sample A, the shape and size of cover 7, or similar factors. Therefore, to effectively and simultaneously perform the ablation of sample A with the first laser light L1 and the ablation of the particles with the second laser light L2, it is desirable to adjust the distance D12 between the first focal point P1 of the first laser light L1 and the second focal point P2 of the second laser light L2 to a suitable distance.

[0072] In contrast, in the laser processing device 20 and the laser processing method according to the present embodiment, the modulation pattern Q (including the Fresnel lens pattern Qf), which is generated based on the focal length f of the lens 42 such that the distance D12 between the first focal point P1 and the second focal point P2 in the optical axis direction of the first laser light L1 and the second laser light L2 assumes the desired adjustment distance Db, is displayed on the spatial light modulator 41. Therefore, the distance D12 between the first focal point P1 and the second focal point P2 can be set to the appropriate adjustment distance Db, and the ablation processing of the sample A using the first laser light L1 and the ablation processing of the particles using the second laser light L2 can be carried out effectively and simultaneously.As described above, with the laser processing device 20 and the laser processing method according to the present embodiment it is possible to effectively suppress a reduction in the permeability of the cover 7 and at the same time shorten the processing time.

[0073] Furthermore, in the laser processing device 20 according to the present embodiment, the spatial light modulator 41 displays the modulation pattern Q, which contains the Fresnel lens pattern Qf that focuses only a portion of the laser light L, and generates the second laser light L2, which contains the portion (modulated light) of the laser light L, and the first laser light L1, which contains the remainder (unmodulated light) of the laser light L, by modulating the laser light L according to the modulation pattern Q. In addition, the control unit 60 causes the spatial light modulator 41 to display the modulation pattern Q, which contains the Fresnel lens pattern Qf with focal length f. QThe formula contains a calculation based on the focal length f of lens 42 and the set distance Db, such that the distance D12 between the first focal point P1 and the second focal point P2 assumes the set distance Db. By using the modulation pattern Q, which contains the Fresnel lens pattern Qf that focuses only a portion of the laser light L, it is thus possible to adjust the distance D12 between the first focal point P1 and the second focal point P2 appropriately to the desired set distance Db, while generating the first laser light L1 and the second laser light L2.

[0074] Furthermore, in the laser processing device 20 according to the present embodiment, the control unit 60 causes the spatial light modulator 41 to display the generated modulation pattern Q such that the ratio between the intensity of the first laser light L1 at the first focal point P1 and the intensity (intensity J2) of the second laser light L2 at the second focal point P2 is the set ratio (i.e., the modulation pattern Q including the Fresnel lens pattern Qf with the gradation value T at which the ratio becomes the set ratio). Therefore, the ratio between the intensity of the first laser light L1 at the first focal point P1 and the intensity of the second laser light L2 at the second focal point P2 can be set to a desired ratio suitable for each processing operation.

[0075] Furthermore, according to the present embodiment, the control unit 60 in the laser processing device 20 causes the spatial light modulator 41 to display the modulation pattern Q, which was generated based on the irradiation conditions of the first laser light L1 and the irradiation conditions of the second laser light L2. Therefore, the irradiation conditions of the first laser light L1 and the irradiation conditions of the second laser light L2 can be adjusted to desired conditions.

[0076] Furthermore, in the laser processing device 20 according to the present embodiment, the irradiation conditions of the second laser light L2 can include the condition under which the beam pattern of the second laser light L2 at the second focal point P2 has a top-hat shape. In this case, the ablation processing of the particles generated by the ablation processing of sample A can be carried out efficiently using the second laser light L2.

[0077] Furthermore, in the laser processing device 20 according to the present embodiment, the irradiation conditions of the second laser light L2 can include the condition under which the plurality of second focal points P2 are formed along the optical axis direction of the second laser light L2. In this case, the ablation of the particles generated by the ablation of the sample A can be carried out using the second laser light L2 over a larger area in the optical axis direction of the second laser light L2. Therefore, for example, stable ablation processing can be carried out even if the second focal point P2 is displaced in the optical axis direction, or even if the processing position (for example, a position on the surface of the cover 7) is displaced in the optical axis direction due to environmental changes, temporal changes, or the like.

[0078] Furthermore, in the laser processing device 20 according to the present embodiment, the irradiation conditions of the first laser light L1 can include the condition under which the plurality of first focal points P1 are formed along the direction that intersects the optical axis direction of the first laser light L1. In this case, the ablation processing of the sample A can be carried out efficiently. Moreover, in this case, for example, by adjusting the polarization direction of the first laser light L1 at the multiple first focal points P1 arranged along the direction that intersects the optical axis direction of the first laser light L1 (for example, by adjusting the polarization directions so that they are orthogonal to each other between adjacent first focal points P1), the formation of a fine periodic structure on the processed cross-section of the sample A can be suppressed.

[0079] Furthermore, the laser radiation unit 40 in the laser processing device 20 according to the present embodiment includes the output control unit 52, which is, for example, a variable attenuator for adjusting the power of the laser light L (i.e., the first laser light L1 and the second laser light L2). Therefore, the treatment output powers of the first laser light L1 and the second laser light L2 can be set to desired values.

[0080] Furthermore, the laser irradiation unit 40 in the laser processing device 20 according to the present embodiment comprises the half-wave plate 54, which is arranged in front of the spatial light modulator 41 and controls the polarization direction of the laser light L incident on the spatial light modulator 41. Therefore, the ratio between modulated light, which is part of the laser light L modulated by the spatial light modulator 41, and unmodulated light, which is part of the laser light L not modulated by the spatial light modulator 41, can be adjusted.

[0081] Furthermore, in the laser processing device 20 according to the present embodiment, the pulse width of the laser light L is 1 ps or less. Therefore, the ablation processing can be carried out effectively. In addition, changes in the properties of the processed cross-section of the sample A due to heat can be suppressed by using an ultrashort pulse laser with a pulse width of 1 ps or less.

[0082] Furthermore, the microscope device 1 according to the present embodiment comprises the laser processing device 20 according to the present embodiment and the first microscope unit 4 and the second microscope unit 5 for observing the sample A arranged on the sample holder 2. Therefore, a microscope device 1 is provided which is capable of suppressing a reduction in the transmittance of the cover 7.

[0083] The above embodiment has described one aspect of the laser processing device, the microscope device, and the laser processing method according to the present invention. Therefore, the laser processing device, the microscope device, and the laser processing method according to the present invention are not limited to the embodiment described above and can be modified as desired.

[0084] For example, the laser processing device 20, as shown in Fig.Figure 8 shows the distance measuring unit 70. The distance measuring unit 70 emits laser beam L3, with the light source 10 emitting laser light L3 for distance measurement in the direction of sample A and cover 7. The laser light L3 for distance measurement has, for example, a different wavelength than the laser light L for processing. Furthermore, the distance measuring unit 70 measures the distance Da between sample A and cover 7 by detecting the reflected light LR1 of the laser light L3 for distance measurement, which is reflected from surface As, which is a laser light incidence surface of sample A, and the reflected light LR2 of the laser light L3 for distance measurement, which is reflected from surface 7s on the sample side of cover 7. In this case, the control unit 60 can detect the set distance Db based on the distance Da measured by the distance measuring unit 70.

[0085] Furthermore, in the embodiment described above, an example was provided in which the irradiation conditions of the first laser light L1 include the condition under which the multiple first focal points P1 are formed along the direction that intersects the optical axis direction of the first laser light L1. In this example, the control unit 60 displays the modulation pattern Q generated on the spatial light modulator 41 based on the irradiation condition such that it includes a diffraction grating pattern for branching the first laser light L1. However, the irradiation conditions of the first laser light L1 are not limited to this and can, for example, include a condition under which a single first focal point P1 of the first laser light L1 is formed.In this case, the control unit 60 displays the modulation pattern Q generated on the basis of the irradiation condition on the spatial light modulator 41 in such a way that it does not contain a diffraction grating pattern for branching the first laser light L1.

[0086] Furthermore, in the embodiment described above, an example was provided in which the irradiation conditions of the second laser light L2 include the condition under which the beam pattern of the second laser light L2 at the second focal point P2 has a top-hat shape. However, the irradiation conditions of the second laser light L2 are not limited to this and can, for example, include a condition under which the beam pattern of the second laser light L2 at the second focal point P2 becomes a Gaussian beam. In this case, the control unit 60 on the spatial light modulator 41 can display the modulation pattern Q generated on the basis of the irradiation condition in such a way that the beam pattern of the second laser light L2 at the second focal point P2 is not modified.

[0087] Furthermore, in the embodiment described above, an example was provided in which the irradiation conditions of the second laser light L2 include the condition under which the multiple second focal points P2 are formed along the optical axis direction of the second laser light L2. In this example, the control unit 60 displays the modulation pattern Q generated based on the irradiation condition on the spatial light modulator 41 such that it contains an axicon lens pattern. However, the irradiation conditions of the second laser light L2 can include a condition under which a single second focal point P2 is formed along the optical axis direction of the second laser light L2. In this case, the control unit 60 displays the modulation pattern Q generated based on the irradiation condition on the spatial light modulator 41 such that it does not contain an axicon lens pattern.

[0088] In this way, the control unit 60 can generate the modulation pattern Q based on (taking into account) the irradiation conditions, regardless of whether control of the first laser light L1 and the second laser light L2 is carried out or not.

[0089] Furthermore, in the embodiment described above, the cover 7 is provided as an example of a transparent element located on the optical axis of the laser light L between the sample A arranged on the sample holder 2 and the laser irradiation unit 40. However, the transparent element can also be the incidence section 11 formed in the chamber 10.

[0090] Incidentally, in the embodiment described above, it is stated that the optical axis of the first laser light L1 is assumed to coincide with the optical axis of the second laser light L2, as indicated in the expression "the distance D12 between the first focal point P1 and the second focal point P2 in the optical axis direction of the first laser light L1 and the second laser light L2".If, however, the modulation pattern Q displayed on the spatial light modulator 41 contains a diffraction grating pattern that diffractes and branches the first laser light L1, the optical axis of the modulated light of the first laser light L1, which is branched into multiple beams and modulated by the diffraction grating pattern, may not coincide with the optical axis of the second laser light L2. In this case, the optical axis of the unmodulated light (zero-order light) of the first laser light L1, which is split into multiple beams and not modulated by the diffraction grating pattern, coincides with the optical axis of the second laser light L2. Even in such a case, the optical axis of the first laser light L1 can be considered to coincide with the optical axis of the second laser light L2.

[0091] Furthermore, in the embodiment described above, an example was described in which the second laser light L2, which contains light modulated by the Fresnel lens pattern Qf, is focused closer to the cover 7 and is intended for particle ablation, while the first laser light L1, which does not contain light modulated by the Fresnel lens pattern Qf, is focused closer to the sample A and is intended for sample A ablation. However, by adjusting the Fresnel lens pattern Qf, the second focal point P2 of the second laser light L2 can also be formed on the sample side with respect to the first focal point P1 of the first laser light L1. That is, the second focal point P2 of the second laser light L2 can be formed at a position on the side opposite the spatial light modulator 41 with respect to the first focal point P1 of the first laser light L1.In this case, the second focal point P2 of the second laser light L2 essentially becomes the first focal point, located at the first position on sample side A with respect to cover 7, and the first focal point P1 of the first laser light L1 essentially becomes the second focal point, located at the second position on cover side 7 with respect to the first focal point. Furthermore, in this case, sample A can be ablated using the second laser light L2, and the particles can be ablated using the first laser light L1.

[0092] Furthermore, in the embodiment described above, an example was described in which, after step S102 for determining the modulation pattern Q to be displayed on the spatial light modulator 41, step S103 for adjusting the power of the laser light L is performed. However, step S103 can be performed before step S102. Industrial applicability

[0093] A laser processing device, a microscope device and a laser processing method are provided with which a reduction in the permeability of the permeable element can be suppressed. List of reference symbols 1 microscope device, 2 sample holders (arrangement unit), 4 first microscope unit (microscope unit), 5 second microscope unit (microscope unit), 7 Cover (permeable element), 20 laser processing devices, 30 laser output units, 40 laser irradiation units, 41 spatial light modulator, 42 Lens (focusing unit), 52 Output control unit (variable attenuator), 54 half-wave plate, 60 control unit, A sample, D12 spacing dB set distance, f focal length, L laser light, L1 first laser light, L2 second laser light, P1 first focal point, P2 second focal point Q modulation pattern, Qf Fresnel lens pattern. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2002-248589 A

[0003]

Claims

[1] Laser processing device comprising: an arrangement unit on which a sample is arranged; a laser output unit configured to output laser light; a laser irradiation unit configured to irradiate the sample arranged on the array unit with the laser light emitted by the laser output unit; and a transparent element that is arranged on an optical axis of the laser light between the sample arranged on the assembly unit and the laser irradiation unit and that transmits the laser light, including the laser irradiation unit a spatial light modulator configured to display a modulation pattern, and configured to generate a first laser light and a second laser light from the laser light by modulating the laser light according to the modulation pattern, and emitting the first laser light and the second laser light, a focusing unit configured to form a first focal point by focusing the first laser light, and configured to form a second focal point by focusing the second laser light, and a control unit configured to control the spatial light modulator, the control unit causes the spatial light modulator to display the modulation pattern generated based on a focal length of the focusing unit, such that by causing the focusing unit to focus the first laser light and the second laser light emitted by the spatial light modulator, the first focal point is localized at a first position on the sample side with respect to the transparent element, the second focal point is localized at a second position on the side of the transparent element with respect to the first focal point, and a distance between the first focal point and the second focal point in an optical axis direction of the first laser light and the second laser light is set to a specified distance, and The laser irradiation unit simultaneously performs ablation processing of the sample using the first laser light and ablation processing of particles generated by the ablation processing of the sample using the second laser light. [2] Laser processing device according to claim 1, wherein the spatial light modulator displays the modulation pattern which includes a lens pattern which focuses only a portion of the laser light, and the second laser light which contains the portion of the laser light, and the first laser light which contains a remainder of the laser light, are generated by modulating the laser light according to the modulation pattern, and The control unit causes the spatial light modulator to display the modulation pattern that contains the lens pattern with a focal length calculated on the basis of the focal length of the focusing unit and the set distance, so that the distance between the first focal point and the second focal point corresponds to the set distance. [3] Laser processing device according to claim 1 or 2, wherein the control unit causes the spatial light modulator to display the generated modulation pattern such that the ratio between an intensity of the first laser light at the first focal point and an intensity of the second laser light at the second focal point assumes a predetermined ratio. [4] Laser processing device according to one of claims 1 to 3, wherein the control unit causes the spatial light modulator to display the modulation pattern that is generated on the basis of the irradiation conditions of the first laser light and the irradiation conditions of the second laser light. [5] Laser processing device according to claim 4, wherein the irradiation conditions of the second laser light include a condition under which a beam pattern of the second laser light at the second focal point assumes a top-hat shape. [6] Laser processing device according to claim 4, wherein the irradiation conditions of the second laser light include a condition under which a plurality of second focal points are formed along the optical axis direction of the second laser light. [7] Laser processing device according to any one of claims 4 to 6, wherein the irradiation conditions of the first laser light comprise a condition under which a plurality of first focal points are formed along a direction that intersects the optical axis direction of the first laser light. [8] Laser processing device according to any one of claims 1 to 7, wherein the laser irradiation unit includes a variable attenuator configured to adjust the power of the laser light. [9] Laser processing device according to any one of claims 1 to 8, wherein the laser irradiation unit includes a half-wave plate arranged in front of the spatial light modulator and controlling the polarization direction of the laser light incident on the spatial light modulator. [10] Laser processing device according to any one of claims 1 to 9, wherein the pulse width of the laser light is 1 ps or less. [11] Laser processing device according to any one of claims 1 to 10, further comprising: a distance measuring unit configured to measure a distance between the sample and the transparent element by detecting light reflected from a laser light incident surface of the sample and light reflected from a surface on the sample side of the transparent element, and the control unit detects the set distance based on the distance measured by the distance measuring unit. [12] Microscope apparatus comprising: the laser processing device according to any one of claims 1 to 11; and a microscope unit configured to observe the sample arranged on the array unit. [13] Laser processing method using a laser processing device comprising an arrangement unit on which a sample is arranged, a laser output unit configured to emit laser light, a laser irradiation unit configured to irradiate the sample arranged on the arrangement unit with the laser light emitted by the laser output unit, and a transparent element arranged on an optical axis of the laser light between the sample arranged on the arrangement unit and the laser irradiation unit and which transmits the laser light, comprising: a processing step to perform an ablation procedure using a first laser light and a second laser light generated from the laser light, the laser irradiation unit comprises a spatial light modulator configured to display a modulation pattern, and configured to generate the first laser light and the second laser light from the laser light by modulating the laser light according to the modulation pattern, and emit the first laser light and the second laser light, a focusing unit configured to form a first focal point by focusing the first laser light, and configured to form a second focal point by focusing the second laser light, and a control unit configured to control the spatial light modulator, the processing step includes a first step in which the spatial light modulator is caused to display the modulation pattern generated on the basis of a focal length of the focusing unit, such that by causing the focusing unit to focus the first laser light and the second laser light emitted by the spatial light modulator, the first focal point is located at a first position on the sample side with respect to the transparent element, the second focal point is located at a second position on the side of the transparent element with respect to the first focal point, and a distance between the first focal point and the second focal point in an optical axis direction of the first laser light and the second laser light is set to a specified distance. and a second step in which, following the first step, an ablation treatment of the sample is performed simultaneously using the first laser light and an ablation treatment of particles generated by the ablation treatment of the sample is performed using the second laser light.

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