Laser processing apparatus, laser processing method, and method for manufacturing semiconductor member

Abstract

Provided is a laser machining apparatus provided with: a light source for outputting laser light; a space light modulator for modulating the laser light output from the light source in accordance with a modulation pattern and outputting the modulated laser light; a collecting lens for collecting the laser light output from the space light modulator to a subject, and forming a collecting spot on the subject; a movement unit for moving the collecting spot relatively to the subject; and a control unit for relatively moving, while setting a position of the collecting spot in a Z direction intersecting with an incident plane of the laser light on the subject to a first Z position by controlling at least the space light modulator and the movement unit, the collecting spot along a line extended in an X direction along the incident plane, thereby performing a first forming process for forming a first reformed area and a first crack extended from the first reformed area on the subject.

Description

[Technical field]

[0001] One aspect of the present disclosure relates to a laser processing apparatus, a laser processing method, and a method for manufacturing a semiconductor member. [Background technology]

[0002] Patent Document 1 describes a laser dicing device. This laser dicing device includes a stage for moving a wafer, a laser head for irradiating the wafer with laser light, and a control unit for controlling each unit. The laser head includes a laser light source for emitting a processing laser light for forming a modified region inside the wafer, a dichroic mirror and a condenser lens arranged in this order on the optical path of the processing laser light, and an AF device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5743123 Summary of the Invention [Problem to be solved by the invention]

[0004] According to the knowledge of the present inventor, there is a demand for laser processing to cut chips, for example, in the shape of a truncated pyramid or a truncated cone, from a wafer, that is, to form a modified region (defining a cutting surface) that becomes a boundary when cutting a chip from a wafer and a crack extending from the modified region obliquely with respect to the thickness direction of the wafer.

[0005] Therefore, an object of one aspect of the present disclosure is to provide a laser processing apparatus, a laser processing method, and a method for manufacturing a semiconductor component that are capable of forming an oblique crack in an object. [Means for solving the problem]

[0006] A laser processing apparatus according to one aspect of the present disclosure includes a light source that outputs laser light, a spatial light modulator for modulating the laser light output from the light source in accordance with a modulation pattern and outputting the modulated laser light, a focusing lens for focusing the laser light output from the spatial light modulator on an object to form a focused spot on the object, and a moving unit for moving the focused spot relatively to the object. By controlling at least the spatial light modulator and the moving unit, a position of the focused spot in a Z direction intersecting an incident surface of the laser light on the object is set to a first Z position, while the focused spot is moved relatively along a line extending in the X direction along the incident surface, thereby forming a first modified region and a first crack extending from the first modified region in the object, and a position of the focused spot in the Z direction to a second Z position closer to the incident surface than the first Z position. and a control unit that carries out a second formation process in which the control unit sets the position of the focused spot in a Y direction that is along the incident surface and intersects the X direction to a first Y position, and in the second formation process, the control unit sets the position of the focused spot in the Y direction to a second Y position shifted from the first Y position, and modulates the laser light by controlling a modulation pattern displayed on the spatial light modulator so that the beam shape of the focused spot in a YZ plane including the Y and Z directions becomes an inclined shape that is inclined in the shift direction at least on the incident surface side from the center of the focused spot, thereby forming a second crack that is inclined in the shift direction in the YZ plane.

[0007] A laser processing method according to one aspect of the present disclosure includes a laser processing step of focusing laser light on an object to form a focused spot of the laser light and moving the focused spot relatively to the object, thereby performing laser processing of the object. The laser processing step includes a first forming step of forming a first modified region and a first crack extending from the first modified region in the object by setting a position of the focused spot in a Z direction intersecting an incident surface of the laser light on the object to a first Z position, and relatively moving the focused spot along a line extending in an X direction along the incident surface, and a second forming step of forming a first crack extending from the first modified region in the object by setting the position of the focused spot in the Z direction to a second Z position closer to the incident surface than the first Z position, and relatively moving the focused spot along the line. and a second formation step of forming a second modified region and a second crack extending from the second modified region by relatively moving the focused spot. In the first formation step, the position of the focused spot in a Y direction that is along the incident surface and intersects the X direction is set to a first Y position, and in the second formation step, the position of the focused spot in the Y direction is set to a second Y position shifted from the first Y position, and the laser light is modulated so that the beam shape of the focused spot in the YZ plane including the Y and Z directions becomes an inclined shape that is inclined in the shift direction at least on the incident surface side of the center of the focused spot, thereby forming the second crack so as to be inclined in the shift direction in the YZ plane.

[0008] In these devices and methods, at a first Z position, the focused spot of the laser light is moved relatively along a line extending in the X direction, thereby forming a first modified region and a first crack extending from the first modified region. The first Z position is a position in the Z direction intersecting with the incident surface of the laser light in the object. In addition, at a second Z position on the incident surface side from the first Z position, the focused spot of the laser light is moved relatively along the line, thereby forming a second modified region and a second crack extending from the second modified region. The focused spot is set to a first Y position in the Y direction when the first modified region and the first crack are formed, and is set to a second Y position shifted from the first Y position in the Y direction when the second modified region and the second crack are formed. The Y direction is a direction intersecting the Z direction and the X direction. Furthermore, when the second modified region and the second crack are formed, the beam shape of the focused spot in the YZ plane is set to an inclined shape that is inclined in the shift direction of the focused spot at least on the incident surface side from the center of the focused spot. According to the findings of the present inventors, by shifting the focused spot in the Y direction and controlling the beam shape of the focused spot in this way, at least the second crack can be made into an oblique crack inclined in the shift direction in the YZ plane. That is, according to this device and method, it is possible to form an oblique crack.

[0009] In the laser processing apparatus according to one aspect of the present disclosure, in the first formation process, the control unit may modulate the laser light so that the beam shape of the focused spot in the YZ plane has an inclined shape that is inclined in the shift direction at least on the incident surface side from the center of the focused spot, thereby forming the first crack so as to be inclined in the shift direction in the YZ plane. In this case, it is possible to reliably form a crack that extends obliquely across the first modified region and the second modified region.

[0010] In the laser processing apparatus according to one aspect of the present disclosure, the modulation pattern may include a coma aberration pattern for imparting coma aberration to the laser light, and in the second forming process, the control unit may perform a first pattern control for forming the beam shape into an inclined shape by controlling the magnitude of the coma aberration due to the coma aberration pattern. According to the knowledge of the present inventor, in this case, the beam shape of the focused spot in the YZ plane is formed into an arc shape. That is, in this case, the beam shape of the focused spot is inclined in the shift direction on the incident surface side from the center of the focused spot, and is inclined in the opposite direction to the shift direction on the opposite side of the incident surface from the center of the focused spot. Even in this case, it is possible to form an oblique crack inclined in the shift direction.

[0011] In the laser processing apparatus according to one aspect of the present disclosure, the modulation pattern includes a spherical aberration correction pattern for correcting the spherical aberration of the laser light, and in the second formation process, the control unit may perform second pattern control for making the beam shape an inclined shape by offsetting the center of the spherical aberration correction pattern in the Y direction with respect to the center of the entrance pupil plane of the focusing lens. According to the knowledge of the present inventor, in this case as well, the beam shape of the focused spot in the YZ plane can be formed into an arc shape, as in the case of using the coma aberration pattern, and an oblique crack inclined in the shift direction can be formed.

[0012] In the laser processing apparatus according to one aspect of the present disclosure, in the second forming process, the control unit may perform a third pattern control for making the beam shape an inclined shape by displaying a modulation pattern asymmetric with respect to an axis line along the X direction on the spatial light modulator. According to the knowledge of the present inventor, in this case, the entire beam shape of the focused spot in the YZ plane can be inclined in the shift direction. Even in this case, it is possible to form an oblique crack inclined in the shift direction.

[0013] In the laser processing apparatus according to one aspect of the present disclosure, the modulation pattern includes an elliptical pattern for making the beam shape of the focused spot in an XY plane including the X and Y directions into an elliptical shape with the X direction as the long side, and in the second forming process, the control unit may perform a fourth pattern control for making the beam shape into an inclined shape by causing the spatial light modulator to display the modulation pattern so that the intensity of the elliptical pattern is asymmetric with respect to an axis line along the X direction. According to the knowledge of the present inventor, even in this case, the beam shape of the focused spot in the YZ plane can be formed into an arc shape, and an oblique crack inclined in the shift direction can be formed.

[0014] In the laser processing apparatus according to one aspect of the present disclosure, the control unit may perform a fifth pattern control in the second forming process to make the beam shape of the focused spot including the multiple focused points into an inclined shape by displaying a modulation pattern for forming multiple focused points arranged along the shift direction in the YZ plane on the spatial light modulator. According to the knowledge of the present inventor, in this case as well, it is possible to form an oblique crack inclined in the shift direction.

[0015] In the laser processing device according to one aspect of the present disclosure, the control unit may perform the first forming process and then the second forming process on a line set on the target object along the X direction. In this way, even when the first forming process and the second forming process are performed separately, it is possible to form an oblique crack.

[0016] In the laser processing device according to one aspect of the present disclosure, the control unit may cause the spatial light modulator to display a modulation pattern including a branching pattern for branching the laser light, thereby simultaneously performing the first formation process and the second formation process on one line set on the target object. In this way, even when the first formation process and the second formation process are performed simultaneously, it is possible to form an oblique crack.

[0017] A method for manufacturing a semiconductor component according to one aspect of the present disclosure includes a laser processing step of laser processing the object by focusing laser light on an object including a semiconductor to form a focused spot of the laser light and moving the focused spot relatively to the object, and a separation step of forming a semiconductor component from the object by separating a part of the object after the laser processing step, wherein the laser processing step includes a first formation step of forming a first modified region and a first crack extending from the first modified region in the object by setting a position of the focused spot in a Z direction intersecting a laser light incident surface on the object to a first Z position, and relatively moving the focused spot along a line extending in the X direction along the incident surface, and a second formation step of forming the focused spot along the line while setting the position of the focused spot in the Z direction to a second Z position closer to the incident surface than the first Z position. and a second formation step of forming a second modified region and a second crack extending from the second modified region by moving the laser beam relative to the incident surface. In the first formation step, the position of the focused spot in a Y direction that is along the incident surface and intersects the X direction is set to a first Y position, and in the second formation step, the position of the focused spot in the Y direction is set to a second Y position shifted from the first Y position, and the laser beam is modulated so that the beam shape of the focused spot in the YZ plane including the Y and Z directions becomes an inclined shape that is inclined in the shift direction at least on the incident surface side of the center of the focused spot, thereby forming the second crack so as to be inclined in the shift direction in the YZ plane. In the separation step, a semiconductor component including a side that is an inclined surface defined by the second crack is formed by separating a part of the object using the first crack and the second crack as boundaries.

[0018] According to this manufacturing method, as in the above-mentioned laser processing method, an oblique crack can be formed in the target object. Therefore, in the separation step, a part of the target object is separated at the crack as a boundary, thereby manufacturing a semiconductor component including an inclined side surface. Effect of the Invention

[0019] According to one aspect of the present disclosure, it is possible to provide a laser processing apparatus, a laser processing method, and a method for manufacturing a semiconductor component that are capable of forming an oblique crack in an object. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a laser processing device according to one embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing the configuration of the laser irradiation unit shown in FIG. [Diagram 3] FIG. 3 is a diagram showing the 4f lens unit shown in FIG. [Figure 4] FIG. 4 is a diagram showing the spatial light modulator shown in FIG. [Diagram 5] FIG. 5 is a cross-sectional view of an object for explaining the findings of oblique crack formation. [Figure 6] FIG. 6 is a cross-sectional view of an object for explaining the findings of oblique crack formation. [Figure 7] FIG. 7 is a diagram showing the beam shape of a focused spot of laser light. [Figure 8] FIG. 8 is a diagram showing the offset of the modulation pattern. [Figure 9] FIG. 9 is a cross-sectional photograph showing the state of formation of the diagonal crack. [Figure 10] FIG. 10 is a schematic plan view of the object. [Figure 11] FIG. 11 is a cross-sectional photograph showing the formation of a diagonal crack. [Figure 12] FIG. 12 is a cross-sectional photograph showing the state of formation of the diagonal crack. [Figure 13] FIG. 13 is a diagram showing an example of a modulation pattern. [Figure 14] FIG. 14 is a diagram showing the intensity distribution on the entrance pupil plane of the condenser lens and the beam shape of the condensed spot. [Figure 15] FIG. 15 is a diagram showing the beam shape of the focused spot and the observation results of the intensity distribution of the focused spot. [Figure 16] FIG. 16 is a diagram showing an example of a modulation pattern. [Figure 17] FIG. 17 is a diagram showing another example of an asymmetric modulation pattern. [Figure 18] FIG. 18 is a diagram showing the intensity distribution on the entrance pupil plane of the condenser lens and the beam shape of the condensed spot. [Figure 19] FIG. 19 is a diagram showing an example of a modulation pattern and the formation of a focused spot. [Figure 20] FIG. 20 is a diagram showing an object according to the first embodiment. [Figure 21] FIG. 21 is a diagram showing a laser processing step according to the first embodiment. [Figure 22] FIG. 22 is a diagram showing a semiconductor member obtained from the target object. [Diagram 23] FIG. 23 is a diagram showing a semiconductor member obtained from the target object. [Figure 24] FIG. 24 is a diagram showing an object according to the second embodiment. [Diagram 25] FIG. 25 is a diagram showing a laser processing step according to the second embodiment. [Figure 26] FIG. 26 is a diagram showing a separation step according to the second embodiment. [Figure 27] FIG. 27 is a diagram showing a semiconductor member obtained from the target object. [Figure 28] FIG. 28 is a cross-sectional view showing a modified example of the laser processing step. [Figure 29] FIG. 29 is a cross-sectional view showing another modified example of the laser processing step. [Diagram 30] FIG. 30 is a plan view showing an object according to a modified example. [Diagram 31] FIG. 31 is a diagram showing an object according to the third embodiment. [Diagram 32] FIG. 32 is a cross-sectional view showing a laser processing step according to the third embodiment. [Diagram 33] FIG. 33 is a cross-sectional view showing a laser processing step according to the third embodiment. [Diagram 34] FIG. 34 is a cross-sectional view showing a grinding step according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] An embodiment will be described in detail below with reference to the drawings. In each drawing, the same or corresponding parts are given the same reference numerals, and duplicated explanations may be omitted. In addition, each drawing may show an orthogonal coordinate system defined by an X-axis, a Y-axis, and a Z-axis. [Laser processing equipment and laser processing overview]

[0022] Fig. 1 is a schematic diagram showing the configuration of a laser processing apparatus according to one embodiment. As shown in Fig. 1, the laser processing apparatus 1 includes a stage 2, a laser irradiation unit 3, driving units (moving units) 4 and 5, and a control unit 6. The laser processing apparatus 1 is an apparatus for forming a modified region 12 in an object 11 by irradiating the object 11 with laser light L.

[0023] The stage 2 supports the object 11, for example, by holding a film attached to the object 11. The stage 2 is rotatable about an axis parallel to the Z direction. The stage 2 may be movable along both the X direction and the Y direction. The X direction and the Y direction are a first horizontal direction and a second horizontal direction that intersect (are perpendicular to) each other, and the Z direction is a vertical direction.

[0024] The laser irradiation unit 3 focuses laser light L, which is transparent to the object 11, and irradiates the object 11. When the laser light L is focused inside the object 11 supported by the stage 2, the laser light L is particularly absorbed in a portion corresponding to a focused spot C (for example, a center Ca described later) of the laser light L, and a modified region 12 is formed inside the object 11. The focused spot C, which will be described in detail later, is a position where the beam intensity of the laser light L is highest or a region within a predetermined range from the center of gravity of the beam intensity.

[0025] The modified region 12 is a region that differs from the surrounding non-modified region in terms of density, refractive index, mechanical strength, and other physical properties. Examples of the modified region 12 include a melting treatment region, a crack region, a dielectric breakdown region, and a refractive index change region. The modified region 12 can be formed such that a crack extends from the modified region 12 to the incident side of the laser light L and to the opposite side. Such modified region 12 and cracks are used, for example, to cut the object 11.

[0026] As an example, when the stage 2 is moved along the X direction and the focused spot C is moved along the X direction relative to the object 11, multiple modified spots 12s are formed in a row along the X direction. One modified spot 12s is formed by irradiating one pulse of laser light L. One row of modified regions 12 is a collection of multiple modified spots 12s lined up in a row. Adjacent modified spots 12s may be connected to each other or separated from each other depending on the relative moving speed of the focused spot C with respect to the object 11 and the repetition frequency of the laser light L.

[0027] The driving unit 4 includes a first moving unit 41 that moves the stage 2 in one direction in a plane intersecting (orthogonal) with the Z direction, and a second moving unit 42 that moves the stage 2 in another direction in a plane intersecting (orthogonal) with the Z direction. As an example, the first moving unit 41 moves the stage 2 along the X direction, and the second moving unit 42 moves the stage 2 along the Y direction. The driving unit 4 also rotates the stage 2 around an axis parallel to the Z direction as a rotation axis. The driving unit 5 supports the laser irradiation unit 3. The driving unit 5 moves the laser irradiation unit 3 along the X direction, the Y direction, and the Z direction. When the stage 2 and / or the laser irradiation unit 3 is moved in a state in which the focused spot C of the laser light L is formed, the focused spot C is moved relative to the object 11. That is, the driving units 4 and 5 are moving units that move at least one of the stage 2 and the laser irradiation unit 3 so that the focused spot C of the laser light L moves relative to the object 11.

[0028] The control unit 6 controls the operations of the stage 2, the laser irradiation unit 3, and the driving units 4 and 5. The control unit 6 has a processing unit, a memory unit, and an input receiving unit (not shown). The processing unit is configured as a computer device including a processor, memory, storage, a communication device, etc. In the processing unit, the processor executes software (programs) loaded into the memory, etc., and controls reading and writing of data in the memory and storage, as well as communication by the communication device. The memory unit is, for example, a hard disk, and stores various data. The input receiving unit is an interface unit that displays various information and receives input of various information from the user. The input receiving unit constitutes a GUI (Graphical User Interface).

[0029] FIG. 2 is a schematic diagram showing the configuration of the laser irradiation unit shown in FIG. 1. FIG. 2 shows a virtual line A indicating the planned laser processing. As shown in FIG. 2, the laser irradiation unit 3 has a light source 31, a spatial light modulator 7, a condenser lens 33, and a 4f lens unit 34. The light source 31 outputs the laser light L, for example, by a pulse oscillation method. Note that the laser irradiation unit 3 may be configured not to have the light source 31 and to introduce the laser light L from outside the laser irradiation unit 3. The spatial light modulator 7 modulates the laser light L output from the light source 31. The condenser lens 33 condenses the laser light L modulated by the spatial light modulator 7 and output from the spatial light modulator 7 toward the object 11.

[0030] 3, the 4f lens unit 34 has a pair of lenses 34A, 34B arranged on the optical path of the laser light L traveling from the spatial light modulator 7 to the condenser lens 33. The pair of lenses 34A, 34B configure a double-telecentric optical system in which the modulation surface 7a of the spatial light modulator 7 and the entrance pupil surface (pupil surface) 33a of the condenser lens 33 are in an imaging relationship. As a result, an image of the laser light L on the modulation surface 7a of the spatial light modulator 7 (an image of the laser light L modulated by the spatial light modulator 7) is transferred (imaged) on the entrance pupil surface 33a of the condenser lens 33. Note that Fs in the figure indicates a Fourier plane.

[0031] 4, the spatial light modulator 7 is a reflective liquid crystal (LCOS: Liquid Crystal on Silicon) spatial light modulator (SLM: Spatial Light Modulator). The spatial light modulator 7 is configured by laminating a drive circuit layer 72, a pixel electrode layer 73, a reflective film 74, an alignment film 75, a liquid crystal layer 76, an alignment film 77, a transparent conductive film 78, and a transparent substrate 79 in this order on a semiconductor substrate 71.

[0032] The semiconductor substrate 71 is, for example, a silicon substrate. The drive circuit layer 72 configures an active matrix circuit on the semiconductor substrate 71. The pixel electrode layer 73 includes a plurality of pixel electrodes 73a arranged in a matrix along the surface of the semiconductor substrate 71. Each pixel electrode 73a is formed of, for example, a metal material such as aluminum. A voltage is applied to each pixel electrode 73a by the drive circuit layer 72.

[0033] The reflective film 74 is, for example, a dielectric multilayer film. The alignment film 75 is provided on the surface of the liquid crystal layer 76 on the reflective film 74 side, and the alignment film 77 is provided on the surface of the liquid crystal layer 76 opposite the reflective film 74. Each alignment film 75, 77 is formed of, for example, a polymer material such as polyimide, and the contact surface of each alignment film 75, 77 with the liquid crystal layer 76 is subjected to, for example, rubbing treatment. The alignment films 75, 77 align the liquid crystal molecules 76a contained in the liquid crystal layer 76 in a fixed direction.

[0034] The transparent conductive film 78 is provided on the surface of the transparent substrate 79 on the alignment film 77 side, and faces the pixel electrode layer 73 with the liquid crystal layer 76 and the like sandwiched therebetween. The transparent substrate 79 is, for example, a glass substrate. The transparent conductive film 78 is formed of, for example, a light-transmitting and conductive material such as ITO. The transparent substrate 79 and the transparent conductive film 78 transmit the laser light L.

[0035] In the spatial light modulator 7 configured as above, when a signal indicating a modulation pattern is input from the control unit 6 to the drive circuit layer 72, a voltage corresponding to the signal is applied to each pixel electrode 73a, and an electric field is formed between each pixel electrode 73a and the transparent conductive film 78. When the electric field is formed, the arrangement direction of the liquid crystal molecules 76a in the liquid crystal layer 76 changes for each region corresponding to each pixel electrode 73a, and the refractive index changes for each region corresponding to each pixel electrode 73a. This state is a state in which the modulation pattern is displayed on the liquid crystal layer 76. The modulation pattern is for modulating the laser light L.

[0036] That is, when the laser light L enters the liquid crystal layer 76 from the outside through the transparent substrate 79 and the transparent conductive film 78 while the modulation pattern is displayed on the liquid crystal layer 76, is reflected by the reflective film 74, and is emitted from the liquid crystal layer 76 to the outside through the transparent conductive film 78 and the transparent substrate 79, the laser light L is modulated according to the modulation pattern displayed on the liquid crystal layer 76. In this way, the spatial light modulator 7 allows modulation of the laser light L (e.g., modulation of the intensity, amplitude, phase, polarization, etc. of the laser light L) by appropriately setting the modulation pattern to be displayed on the liquid crystal layer 76. The modulation surface 7a shown in FIG. 3 is, for example, the liquid crystal layer 76.

[0037] As described above, the laser light L output from the light source 31 is incident on the condenser lens 33 via the spatial light modulator 7 and the 4f lens unit 34, and is focused by the condenser lens 33 inside the target 11, thereby forming the modified region 12 and a crack extending from the modified region 12 in the target 11 at the focused spot C. Furthermore, the control unit 6 controls the drive units 4 and 5 to move the focused spot C relative to the target 11, thereby forming the modified region 12 and the crack along the movement direction of the focused spot C. [Explanation of findings regarding diagonal crack formation]

[0038] Here, the moving direction (processing proceeding direction) of the focused spot C at this time is defined as the X direction. Moreover, the direction intersecting (orthogonal) with the first surface 11a, which is the incident surface of the laser light L in the object 11, is defined as the Z direction. Moreover, the direction intersecting (orthogonal) with the X direction and the Z direction is defined as the Y direction. The X direction and the Y direction are directions along the first surface 11a. Note that the Z direction may be defined as the optical axis of the focusing lens 33, the optical axis of the laser light L focused toward the object 11 via the focusing lens 33.

[0039] As shown in Fig. 5, there is a demand for forming a crack obliquely along a line D inclined with respect to the Z direction and the Y direction (here, a line D inclined at a predetermined angle θ from the Y direction) in an intersecting plane (YZ plane E including the Y direction and the Z direction) that intersects with the X direction, which is the processing progress direction. The inventor's findings regarding such oblique crack formation will be explained with reference to a processing example.

[0040] Here, modified regions 12a and 12b are formed as the modified region 12. As a result, a crack 13a extending from the modified region 12a and a crack 13b extending from the modified region 12b are connected to form a crack 13 extending obliquely along the line D. Here, first, as shown in FIG. 6, a focused spot C1 is formed with the first surface 11a of the object 11 as the incident surface of the laser light L. Meanwhile, a focused spot C2 is formed on the first surface 11a side of the focused spot C1 with the first surface 11a as the incident surface of the laser light L. At this time, the focused spot C2 is shifted by a distance Sz in the Z direction from the focused spot C1, and is shifted by a distance Sy in the Y direction from the focused spot C1. The distances Sz and Sy correspond to the inclination of the line D, for example.

[0041] On the other hand, as shown in Fig. 7, by modulating the laser light L using the spatial light modulator 7, the beam shape of the focused spot C (at least the focused spot C2) in the YZ plane E is made into an inclined shape inclined in the shift direction (here, the negative side of the Y direction) with respect to the Z direction at least on the first surface 11a side from the center Ca of the focused spot C. In the example of Fig. 7, on the first surface 11a side from the center Ca, it is inclined to the negative side of the Y direction with respect to the Z direction, and also on the opposite side of the first surface 11a from the center Ca, it is inclined to the negative side of the Y direction with respect to the Z direction. Note that the beam shape of the focused spot C in the YZ plane E refers to the intensity distribution of the laser light L at the focused spot C in the YZ plane E.

[0042] In this way, by shifting at least two focused spots C1 and C2 in the Y direction and making the beam shape of at least the focused spot C2 (here, both focused spots C1 and C2) an inclined shape, it is possible to form a crack 13 extending obliquely, as shown in (a) of Fig. 8. Note that, for example, by controlling the modulation pattern of the spatial light modulator 7, the focused spots C1 and C2 may be simultaneously formed by branching the laser light L to form the modified region 12 and the crack 13 (multi-focus processing), or the modified region 12a and the crack 13a may be formed by forming the focused spot C1, and then the modified region 12b and the crack 13b may be formed by forming the focused spot C2 (single-pass processing).

[0043] In addition, by forming another focused spot between the focused spots C1 and C2, as shown in (b) of Figure 8, another modified area 12c can be interposed between the modified areas 12a and 12b, thereby forming a longer, diagonally extending crack 13.

[0044] Next, knowledge for making the beam shape of the focused spot C in the YZ plane E into an inclined shape will be described. First, the definition of the focused spot C will be specifically described. Here, the focused spot C is a region within a predetermined range from the center Ca (for example, a range of ±25 μm from the center Ca in the Z direction). As described above, the center Ca is the position where the beam intensity is highest, or the position of the center of gravity of the beam intensity. The position of the center of gravity of the beam intensity is the position where the center of gravity of the beam intensity is located on the optical axis of the laser light L in a state where modulation is not performed by a modulation pattern that shifts the optical axis of the laser light L, such as a modulation pattern for branching the laser light L. The position where the beam intensity is highest or the center of gravity of the beam intensity can be obtained as follows. That is, the laser light L is irradiated to the object 11 in a state where the output of the laser light L is lowered to such an extent that the modified region 12 is not formed in the object 11 (lower than the processing threshold). At the same time, the reflected light of the laser light L from the surface of the object 11 opposite to the incident surface of the laser light L (here, the second surface 11b) is captured by a camera at a number of positions F1 to F7 in the Z direction shown in Fig. 15. This makes it possible to obtain the position where the beam intensity is highest and the center of gravity based on the obtained images. The modified region 12 is formed near this center Ca.

[0045] In order to make the beam shape at the focused spot C an inclined shape, there is a method of offsetting the modulation pattern. More specifically, various patterns such as a distortion correction pattern for correcting wavefront distortion, a grating pattern for branching laser light, a slit pattern, an astigmatism pattern, a coma aberration pattern, and a spherical aberration correction pattern are displayed on the spatial light modulator 7 (a pattern in which these are superimposed is displayed). Of these, as shown in Fig. 9, the beam shape at the focused spot C can be adjusted by offsetting the spherical aberration correction pattern Ps.

[0046] In the example of Fig. 9, on the modulation plane 7a, the center Pc of the spherical aberration correction pattern Ps is offset by an offset amount Oy1 on the negative side in the Y direction with respect to the center Lc (of the beam spot) of the laser light L. As described above, the modulation plane 7a is transferred to the entrance pupil plane 33a of the condenser lens 33 by the 4f lens unit 34. Therefore, the offset on the modulation plane 7a becomes an offset on the positive side in the Y direction on the entrance pupil plane 33a. That is, on the entrance pupil plane 33a, the center Pc of the spherical aberration correction pattern Ps is offset by an offset amount Oy2 on the positive side in the Y direction from the center Lc of the laser light L and the center of the entrance pupil plane 33a (which coincides with the center Lc here).

[0047] In this way, by offsetting the spherical aberration correction pattern Ps, the beam shape of the focused spot C of the laser light L is deformed into an arc-like inclined shape as shown in Fig. 7. Offsetting the spherical aberration correction pattern Ps as described above corresponds to imparting coma aberration to the laser light L. Therefore, the beam shape of the focused spot C may be made into an inclined shape by including a coma aberration pattern for imparting coma aberration to the laser light L in the modulation pattern of the spatial light modulator 7. Note that as the coma aberration pattern, a pattern equivalent to the ninth term of the Zernike polynomial (Y component of third-order coma aberration) and in which coma aberration occurs in the Y direction can be used.

[0048] Next, the findings regarding the relationship between the crystallinity of the object 11 and the crack 13 will be described. FIG. 10 is a schematic plan view of the object. Here, the object 11 is a silicon wafer (t 775 μm, <100> , 1 Ω·cm), and a notch 11d is formed. For this object 11, a first processing example in which the X direction, which is the processing proceeding direction, is aligned with the 0° (100) plane is shown in Fig. 11(a), a second processing example in which the X direction is aligned with 15° is shown in Fig. 11(b), a third processing example in which the X direction is aligned with 30° is shown in Fig. 12(a), and a fourth processing example in which the X direction is aligned with the 45° (100) plane is shown in Fig. 12(b). In each processing example, the angle θ of the line D from the Y direction in the YZ plane is set to 71°.

[0049] In each processing example, a single pass processing is performed in which the condensed spot C1 is moved relatively in the X direction in the first pass to form the modified region 12a and the crack 13a, and then the condensed spot C2 is moved relatively in the X direction in the second pass to form the modified region 12b and the crack 13b. The processing conditions for the first and second passes are as follows. Note that CP below indicates the strength of the condensation correction, and coma (LBA offset Y) indicates the offset amount of the spherical aberration correction pattern Ps in the Y direction in pixel units of the spatial light modulator 7.

[0050] <First pass> Z direction position: 161μm CP:-18 Output: 2W Speed: 530mm / s Frequency: 80kHz Frame(LBA offset Y):-5 Y direction position: 0

[0051] <Second pass> Z direction position: 151μm CP:-18 Output: 2W Speed: 530mm / s Frequency: 80kHz Frame(LBA offset Y):-5 Y direction position: 0.014mm

[0052] 11 and 12, in either case, a crack 13 could be formed along a line D inclined at 71° with respect to the Y direction. That is, regardless of the influence of the (110) plane, the (111) plane, the (100) plane, etc., which are the main cleavage planes in the object 11, i.e., regardless of the crystal structure of the object 11, a crack 13 extending obliquely along the desired line D could be formed.

[0053] The control of the beam shape for forming the obliquely extending crack 13 is not limited to the above example. Next, another example for forming the beam shape into an inclined shape will be described. As shown in (a) of FIG. 13, the laser light L may be modulated by a modulation pattern PG1 asymmetric with respect to the axis Ax along the X direction, which is the processing progress direction, to form the beam shape of the focused spot C into an inclined shape. The modulation pattern PG1 includes a grating pattern Ga on the negative side of the Y direction from the axis Ax along the X direction passing through the center Lc of the beam spot of the laser light L in the Y direction, and includes a non-modulated region Ba on the positive side of the axis Ax in the Y direction. In other words, the modulation pattern PG1 includes the grating pattern Ga only on the positive side of the axis Ax in the Y direction. Note that (b) of FIG. 13 is obtained by inverting the modulation pattern PG1 of (a) of FIG. 13 so as to correspond to the entrance pupil surface 33a of the focusing lens 33.

[0054] Fig. 14(a) shows the intensity distribution of the laser light L on the entrance pupil plane 33a of the focusing lens 33. As shown in Fig. 14(a), by using such a modulation pattern PG1, the portion of the laser light L that is incident on the spatial light modulator 7 and that is modulated by the grating pattern Ga does not enter the entrance pupil plane 33a of the focusing lens 33. As a result, as shown in Fig. 14(b) and Fig. 15, the beam shape of the focused spot C in the YZ plane E can be made to be an inclined shape whose entirety is inclined in one direction with respect to the Z direction.

[0055] That is, in this case, the beam shape of the focused spot C is inclined toward the negative side of the Y direction with respect to the Z direction on the first surface 11a side of the center Ca of the focused spot C, and is inclined toward the positive side of the Y direction with respect to the Z direction on the opposite side of the first surface 11a from the center Ca of the focused spot C. Each diagram in FIG. 15(b) shows the intensity distribution in the XY plane of the laser light L at each position F1 to F7 in the Z direction shown in FIG. 15(a), and is an actual observation result by a camera. Even when the beam shape of the focused spot C is controlled in this way, a crack 13 extending obliquely can be formed as in the above example.

[0056] Furthermore, as modulation patterns asymmetric with respect to the axis Ax, modulation patterns PG2, PG3, and PG4 shown in Fig. 16 can also be adopted. The modulation pattern PG2 includes a non-modulation region Ba and a grating pattern Ga arranged in order in a direction away from the axis Ax on the negative side of the axis Ax in the Y direction, and includes a non-modulation region Ba on the positive side of the axis Ax in the Y direction. In other words, the modulation pattern PG2 includes a grating pattern Ga in a part of the region on the negative side of the axis Ax in the Y direction.

[0057] The modulation pattern PG3 includes non-modulated regions Ba and grating patterns Ga arranged in sequence in a direction away from the axis Ax on the negative side of the axis AX in the Y direction, and also includes non-modulated regions Ba and grating patterns Ga arranged in sequence in a direction away from the axis Ax on the positive side of the axis Ax in the Y direction. The modulation pattern PG3 is made asymmetric with respect to the axis Ax by varying the proportions of non-modulated regions Ba and grating patterns Ga between the positive side of the axis Ax in the Y direction and the negative side in the Y direction (by making the non-modulated regions Ba relatively narrower on the negative side in the Y direction).

[0058] The modulation pattern PG4, like the modulation pattern PG2, includes a grating pattern Ga in a part of the region on the negative side of the axis Ax in the Y direction. In the modulation pattern PG4, the region in which the grating pattern Ga is provided is also a part in the X direction. That is, the modulation pattern PG4 includes a non-modulated region Ba, a grating pattern Ga, and a non-modulated region Ba arranged in order in the X direction in the region on the negative side of the axis Ax in the Y direction. Here, the grating pattern Ga is arranged in a region including an axis Ay along the Y direction passing through the center Lc of the beam spot of the laser light L in the X direction.

[0059] Any of the above modulation patterns PG2 to PG4 can be used to make the beam shape of the focused spot C inclined toward the negative side of the Y direction with respect to the Z direction at least on the first surface 11a side from the center Ca. That is, in order to control the beam shape of the focused spot C to be inclined toward the negative side of the Y direction with respect to the Z direction at least on the first surface 11a side from the center Ca, it is possible to use an asymmetric modulation pattern such as the modulation patterns PG1 to PG4 or including a grating pattern Ga, without being limited to the modulation patterns PG1 to PG4.

[0060] Furthermore, the asymmetric modulation pattern for making the beam shape of the focused spot C into an inclined shape is not limited to one that uses a grating pattern Ga. Fig. 17 is a diagram showing another example of an asymmetric modulation pattern. As shown in Fig. 17(a), the modulation pattern PE includes an elliptical pattern Ew on the negative side of the axis Ax in the Y direction, and includes an elliptical pattern Es on the positive side of the axis Ax in the Y direction. Note that Fig. 17(b) is obtained by inverting the modulation pattern PE in Fig. 17(a) so as to correspond to the entrance pupil surface 33a of the focusing lens 33.

[0061] As shown in FIG. 17(c), both of the elliptical patterns Ew and Es are patterns for making the beam shape of the focused spot C on the XY plane including the X and Y directions into an elliptical shape with the X direction as the longitudinal direction. However, the elliptical patterns Ew and Es have different modulation intensities. More specifically, the modulation intensity by the elliptical pattern Es is made larger than the modulation intensity by the elliptical pattern Ew. That is, the focused spot Cs formed by the laser light L modulated by the elliptical pattern Es is made to have an elliptical shape longer in the X direction than the focused spot Cw formed by the laser light L modulated by the elliptical pattern Ew. Here, a relatively strong elliptical pattern Es is arranged on the negative side of the Y direction from the axis Ax.

[0062] As shown in FIG. 18(a), by using such a modulation pattern PE, the beam shape of the focused spot C in the YZ plane E can be made to be an inclined shape that is inclined toward the negative Y direction with respect to the Z direction on the first surface 11a side from the center Ca. Particularly in this case, the beam shape of the focused spot C in the YZ plane E is inclined toward the negative Y direction with respect to the Z direction even on the side opposite to the first surface 11a from the center Ca, and becomes an arc shape as a whole. Each diagram in FIG. 18(b) shows the intensity distribution in the XY plane of the laser light L at each position H1 to F8 in the Z direction shown in FIG. 18(a), and is an actual observation result by a camera.

[0063] Furthermore, the modulation pattern for making the beam shape of the focused spot C into an inclined shape is not limited to the asymmetric pattern described above. As an example, as shown in FIG. 19, such a modulation pattern may be a pattern for modulating the laser light L so that the focused points CI are formed at multiple positions in the YZ plane E and the focused spot C having an inclined shape (including the multiple focused points CI) is formed as a whole of the multiple focused points CI. As an example, such a modulation pattern can be formed based on an axicon lens pattern. When such a modulation pattern is used, the modified region 12 itself can also be formed obliquely in the YZ plane E. Therefore, in this case, the oblique crack 13 can be accurately formed according to the desired inclination. On the other hand, when such a modulation pattern is used, the length of the crack 13 tends to be shorter than the other examples described above. Therefore, by using various modulation patterns according to requirements, desired processing can be performed.

[0064] The focal point CI is, for example, a point where unmodulated laser light is focused. As described above, according to the knowledge of the present inventor, by shifting at least two modified regions 12a, 12b in the Y direction and the Z direction in the YZ plane E and by making the beam shape of the focal spot C inclined in the YZ plane, it is possible to form a crack 13 that extends obliquely so as to be inclined in the Y direction with respect to the Z direction.

[0065] In addition, when controlling the beam shape, if the offset of the spherical aberration correction pattern is used, if the coma aberration pattern is used, or if the elliptical pattern is used, processing with high energy is possible compared to when a diffraction grating pattern is used to cut off part of the laser light. Furthermore, these cases are effective when emphasis is placed on the formation of cracks. Furthermore, when the coma aberration pattern is used, it is possible to make only the beam shape of some of the focused spots an inclined shape in the case of multi-focus processing. Furthermore, when an axicon lens pattern is used, the use of other patterns is effective compared to other patterns when emphasis is placed on the formation of modified regions. [First embodiment]

[0066] Next, a method for manufacturing a semiconductor member and a laser processing device according to the first embodiment will be described. First, an outline will be described. FIG. 20 is a diagram showing an object according to the first embodiment. FIG. 20(a) is a plan view, and FIG. 20(b) is a cross-sectional view taken along the line XXb-XXb in FIG. 20(a). The object 11 shown in FIG. 20 includes, for example, a semiconductor. The object 11 is, for example, a semiconductor wafer (for example, a silicon wafer). The object 11 includes a first surface 11a and a second surface 11b opposite to the first surface 11a. Here, the object 11 is cut in a lattice pattern to form a plurality of semiconductor members 50. For this purpose, a plurality of lines A parallel to the first surface 11a and the second surface 11b are set in a lattice pattern on the object 11 as lines to be cut. The lines A are, for example, virtual lines.

[0067] Here, a pair of lines Aa1, Aa2 and a pair of lines Ab1, Ab2 of the line A are shown. The lines Aa1, Aa2 extend in one direction parallel to each other when viewed from the Z direction. The lines Ab1, Ab2 intersect the lines Aa1, Aa2 when viewed from the Z direction and extend in one direction parallel to each other. Here, the object 11 is supported by the stage 2 so that the first surface 11a faces the condenser lens 33 side.

[0068] In this embodiment, the laser light L is irradiated to such an object 11 while moving the focused spot C of the laser light L along each of the lines A relative to the object 11, and the modified region 12 and the crack 13 are formed along each of the lines A. At this time, the focused spot C is moved relatively in the X direction. That is, here, the X direction is the processing proceeding direction. In this embodiment, in the intersecting plane (YZ plane E) intersecting (perpendicular to) the X direction, which is the processing proceeding direction, the crack 13 inclined in the Y direction with respect to the Z direction is formed. In (b) of FIG. 20, the extension direction of the desired crack 13 is indicated by the line D. The adjacent lines D in the YZ plane E are inclined so as to move away from each other as they move from the second surface 11b to the first surface 11a. That is, in this embodiment, the cracks 13 adjacent to each other in the Y direction are formed obliquely so as to move away from each other as they move from the second surface 11b to the first surface 11a.

[0069] Next, a method for manufacturing a semiconductor member and a laser processing device according to the present embodiment will be specifically described. In this manufacturing method, first, the object 11 as described above is prepared, and the object 11 is supported by the stage 2 so that the first surface 11a faces the condenser lens 33 and the lines Aa1 and Aa2 are aligned in the X direction.

[0070] In this state, first, for one line Aa1, laser light L (laser light L1, L2) is focused on the object 11 to form a focused spot C (focused spots C1, C2) of the laser light L, and the focused spot C is moved relative to the object 11 in the X direction, thereby performing a laser processing step to laser process the object 11.

[0071] 21, a first forming step is performed in which the position of the focused spot C1 in the Z direction intersecting with the first surface 11a, which is the incident surface of the laser light L1 in the object 11, is set to a first Z position Z1 while the focused spot C1 is relatively moved along a line Aa1 extending in the X direction to form a modified region (first modified region) 12a and a crack (first crack) 13a extending from the modified region 12a in the object 11. In the first forming step, the position of the focused spot C1 in the Y direction, which is along the first surface 11a and intersects the X direction, is set to a first Y position Y1.

[0072] In the laser processing step, the position of the focal spot C2 of the laser light L2 in the Z direction is set to a second Z position Z2 closer to the first surface 11a (incident surface) than the first Z position Z1 of the focal spot C1 in the first formation step, while the focal spot C2 is relatively moved along the line Aa1 in the X direction to form the modified region 12b (second modified region) and a crack (second crack) 13b extending from the modified region 12b. In the second formation step, the position of the focal spot C2 in the Y direction is set to a second Y position Y2 shifted from the first Y position Y1 of the focal spot C1. In the second formation step, the laser light L2 is modulated so that the beam shape of the focal spot C2 in the YZ plane E including the Y and Z directions becomes an inclined shape inclined in the direction of the shift at least on the first surface 11a side from the center of the focal spot C2. As a result, the crack 13b is formed in the YZ plane E so as to be inclined in the direction of the shift. The distance Sy (shift amount) between the focused spots C1 and C2 in the Y direction is smaller than the distance in the Y direction between the two lines Aa1 and Aa2 adjacent to each other in the Y direction.

[0073] In the first forming step, as in the second forming step, the laser light L1 is modulated so that the beam shape of the focused spot C1 in the YZ plane E including the Y and Z directions is an inclined shape that is inclined in the direction of the shift at least on the first surface 11a side from the center of the focused spot C1. As a result, the crack 13a and the crack 13b are connected to each other, and a crack 13 that extends obliquely across the modified regions 12a and 12b is formed. The crack 13 may or may not reach the first surface 11a and / or the second surface 11b of the object 11 (this can be set appropriately depending on the required processing mode).

[0074] The laser processing steps including the first and second forming steps can be performed, for example, by the control unit 6 of the laser processing apparatus 1 controlling each unit of the laser processing apparatus 1. That is, in the laser processing apparatus 1 according to this embodiment, the control unit 6 controls the spatial light modulator 7 and the driving units 4 and 5 to perform a first forming process in which the position of the light-focusing spot C1 in the Z direction is set to a first Z position Z1, and the light-focusing spot C1 is relatively moved along a line Aa1 extending in the X direction to form the modified region 12a and the crack 13a in the target object 11, and a second forming process in which the position of the light-focusing spot C2 in the Z direction is set to a second Z position Z2 on the first surface 11a side from the first Z position Z1, and the light-focusing spot C2 is relatively moved along the line Aa1 to form the modified region 12b and the crack 13b.

[0075] In the first formation process, the control unit 6 sets the position of the focused spot C1 in the Y direction to the first Y position Y1. In the second formation process, the control unit 6 sets the position of the focused spot C2 in the Y direction to the second Y position Y2 shifted from the first Y position Y1, and modulates the laser light L2 by controlling the modulation pattern displayed on the spatial light modulator 7 so that the beam shape of the focused spot C2 in the YZ plane E becomes an inclined shape that is inclined in the direction of the shift at least on the first surface 11a side from the center of the focused spot C2. In the first formation process, as in the second formation process, the control unit 6 modulates the laser light L1 so that the beam shape of the focused spot C1 in the YZ plane E becomes an inclined shape that is inclined in the direction of the shift at least on the first surface 11a side from the center of the focused spot C1. The modulation pattern for making the beam shape into an inclined shape is as described above.

[0076] That is, the modulation pattern here includes a coma aberration pattern for imparting coma aberration to the laser light L, and at least in the second formation process, the control unit 6 can perform the first pattern control for making the beam shape of the focused spot C2 an inclined shape by controlling the magnitude of coma aberration due to the coma aberration pattern. As described above, imparting coma aberration to the laser light L is synonymous with offsetting the spherical aberration correction pattern.

[0077] Therefore, the modulation pattern here includes a spherical aberration correction pattern Ps for correcting the spherical aberration of the laser light L, and at least in the second formation process, the control unit 6 may perform second pattern control to make the beam shape of the focused spot C2 an inclined shape by offsetting the center Pc of the spherical aberration correction pattern Ps in the Y direction relative to the center of the entrance pupil surface 33a of the focusing lens 33.

[0078] Alternatively, in the second formation process, the control unit 6 may perform a third pattern control for making the beam shape of the focused spot C2 an inclined shape by causing the spatial light modulator 7 to display a modulation pattern asymmetric with respect to the axis Ax along the X direction. The modulation pattern asymmetric with respect to the axis Ax may be the modulation patterns PG1 to PG4 including a grating pattern Ga, or may be the modulation pattern PE including elliptical patterns Es, Ew (or may include both).

[0079] That is, the modulation pattern here includes elliptical patterns Es, Ew for making the beam shape of the focused spot C in the XY plane an elliptical shape with the X direction as the longitudinal direction, and in the second formation process, the control unit 6 may perform a fourth pattern control for making the beam shape of the focused spot C2 an inclined shape by causing the spatial light modulator 7 to display the modulation pattern PE so that the intensities of the elliptical patterns Es, Ew are asymmetric with respect to the axis Ax along the X direction.

[0080] Furthermore, in the second forming process, the control unit 6 may perform a fifth pattern control for making the beam shape of the focused spot C2 including the multiple focused points CI into an inclined shape by causing the spatial light modulator 7 to display a modulation pattern (for example, the above-mentioned axicon lens pattern PA) for forming multiple focused points CI arranged along the shift direction in the YZ plane E. The above various patterns may be arbitrarily combined and superimposed. That is, the control unit 6 can execute the first pattern control to the fifth pattern control in any combination.

[0081] The first forming step (first forming process) and the second forming step (second forming process) may be performed simultaneously (multifocal processing) or sequentially (single-pass processing). That is, the control unit 6 may perform the first forming process on one line A (e.g., line Aa1) and then the second forming process. Alternatively, the control unit 6 may perform the first forming process and the second forming process simultaneously on one line A (e.g., line Aa1) set on the object 11 by causing the spatial light modulator 7 to display a modulation pattern including a branching pattern for branching the laser light L into laser light L1 and L2.

[0082] In the method for producing a semiconductor member according to this embodiment, the above laser processing step is performed on all of the lines A. As a result, modified regions 12 and cracks 13 are formed along all of the lines A. Thereafter, in the method for producing a semiconductor member according to this embodiment, a separation step is performed in which a part of the object 11 is separated to form a semiconductor member 50 from the object 11.

[0083] More specifically, in the separation step, a part of the object 11 is separated using the crack 13 as a boundary to form a semiconductor member 50 including a side surface 50s that is an inclined surface defined by at least the crack 13b, as shown in (a) of Fig. 22. Here, the object 11 is cut along the line A using the crack 13 as a boundary to form a plurality of semiconductor members 50. The side surface 50s is an outer surface of the semiconductor member 50, and is a surface that connects the first surface 50a of the semiconductor member 50, which is a part of the first surface 11a, and the second surface 50b of the semiconductor member 50, which is a part of the second surface 11b, and is inclined with respect to the normal to the first surface 50a and the second surface 50b.

[0084] In this manner, a semiconductor member 50 is obtained (see FIG. 22(a)). The above-described method for producing a semiconductor member includes the laser processing method according to this embodiment. The laser processing method according to this embodiment includes the laser processing step described above.

[0085] As shown in FIG. 22(b), a stacked semiconductor element 50A can be constructed by stacking a plurality of semiconductor members 50 obtained by the semiconductor member manufacturing method according to this embodiment so that the first surface 50a of one semiconductor member 50 faces the second surface 50b of another semiconductor member 50. Here, the area of ​​the first surface 50a is larger than the area of ​​the second surface 50b. Therefore, in the semiconductor element 50A, a region that is not covered by the second surface 50b of another semiconductor member 50 (exposed from the second surface 50b) is formed on the first surface 50a of the one semiconductor member 50. Therefore, by using the region on the first surface 50a that is not covered by the second surface 50b as a location for setting the wire W for wire bonding, it is possible to electrically connect the semiconductor members 50 to each other without using an internal structure such as a through electrode.

[0086] 23(a), for example, a semiconductor element 50B can be constructed by arranging and placing (by tiling) a plurality of semiconductor members 50 on a substrate 51 so that the first surfaces 50a face in the same direction. In this case, since the side surfaces 50s of adjacent semiconductor members 50 are spaced apart from each other according to the inclination, even if protrusions are generated on the side surfaces 50s when the semiconductor members 50 are formed, interference of the protrusions between adjacent semiconductor members 50 can be avoided, and a plurality of semiconductor members 50 can be arranged closely together.

[0087] 23(b), in the separation step, a portion 55 may be separated from the target object 11 to form a semiconductor member 50C as another remaining portion. More specifically, in the separation step, the target object 11 is etched to allow the etching to proceed along the crack 13 and the modified region 12, thereby removing the portion 55 from the target object 11. As a result, a semiconductor member 50C including a side surface 50s that is an inner surface defined by the crack 13 is obtained.

[0088] Furthermore, as shown in FIG. 23(c), a chamfered semiconductor member 50D can be formed. In this case, as an example, in the laser processing step, another modified region is formed closer to the first surface 11a than the modified region 12b and the crack 13b, and a vertical crack extending from the modified region along the Z direction is formed so as to connect to the crack 13. Then, in the separation step, a part is separated from the object 11 with the crack 13 and the vertical crack as boundaries, thereby obtaining a semiconductor member 50D including a side surface 50s that is an inclined surface defined by the crack 13 and a side surface 50r that is a vertical surface defined by the vertical crack. The semiconductor member 50D has a chamfered shape by connecting the inclined side surface 50s between the side surface 50r and the first surface 50a. This prevents chipping.

[0089] As described above, in the manufacturing method (laser processing method) of a semiconductor member according to this embodiment and the laser processing apparatus 1, the focused spot C1 of the laser light L1 is moved relatively along the line Aa1 extending in the X direction at the first Z position Z1, thereby forming the modified region 12a and the crack 13a. In addition, the focused spot C2 of the laser light L2 is moved relatively along the line Aa1 at the second Z position Z2, which is closer to the first surface 11a than the first Z position Z1, thereby forming the modified region 12b and the crack 13b. The focused spot C1 is set to the first Y position Y1 in the Y direction when the modified region 12a and the crack 13a are formed, and is set to the second Y position Y2 shifted from the first Y position Y1 in the Y direction when the modified region 12b and the crack 13b are formed.

[0090] Furthermore, when the modified region 12b and the crack 13b are formed, the beam shape of the focused spot C2 in the YZ plane E is made to be an inclined shape that is inclined in the shift direction of the focused spot C2 at least on the first surface 11a side from the center of the focused spot C2. According to the knowledge of the present inventor, by shifting the focused spot C2 in the Y direction and controlling the beam shape of the focused spot C2 in this way, at least the crack 13b can be made into an oblique crack inclined in the shift direction in the YZ plane E. In other words, an oblique crack can be formed.

[0091] Furthermore, in the laser processing apparatus 1 according to this embodiment, in the first formation process, the control unit 6 modulates the laser light L so that the beam shape of the focused spot C1 in the YZ plane E has an inclined shape that is inclined in the shift direction at least on the first surface 11a side from the center of the focused spot C1, thereby forming the crack 13a so as to be inclined in the shift direction in the YZ plane E. This makes it possible to reliably form the crack 13 that extends obliquely across the modified region 12a and the modified region 12b.

[0092] In addition, in the laser processing apparatus 1 according to the present embodiment, the modulation pattern may include a coma aberration pattern for imparting positive coma aberration to the laser light L. In this case, the control unit 6 may perform the first pattern control for making the beam shape of the focused spot C an inclined shape by controlling the magnitude of the coma aberration due to the coma aberration pattern in the second formation process. According to the knowledge of the present inventor, in this case, the beam shape of the focused spot C in the YZ plane E is formed in an arc shape. That is, in this case, the beam shape of the focused spot C is inclined in the shift direction on the first surface 11a side from the center Ca of the focused spot C, and is inclined in the opposite direction to the shift direction on the second surface 11b side from the center Ca of the focused spot C. Even in this case, it is possible to form an oblique crack inclined in the shift direction.

[0093] In addition, in the laser processing apparatus 1 according to the present embodiment, the modulation pattern may include a spherical aberration correction pattern Ps for correcting the spherical aberration of the laser light L. In this case, the control unit 6 may perform second pattern control for making the beam shape of the focused spot C an inclined shape by offsetting the center Pc of the spherical aberration correction pattern Ps in the Y direction with respect to the center of the entrance pupil surface 33a of the focusing lens 33 in the second formation process. According to the knowledge of the present inventor, in this case as well, the beam shape of the focused spot C in the YZ plane E can be formed into an arc shape, as in the case of using the coma aberration pattern, and an oblique crack inclined in the shift direction can be formed.

[0094] Furthermore, in the laser processing apparatus 1 according to this embodiment, the control unit 6 may perform a third pattern control for making the beam shape an inclined shape by causing the spatial light modulator 7 to display a modulation pattern asymmetric with respect to the axis line Ax along the X direction in the second formation process. According to the knowledge of the present inventor, in this case, the entire beam shape of the focused spot C in the YZ plane E can be inclined in the shift direction. Even in this case, it is possible to form an oblique crack inclined in the shift direction.

[0095] In addition, in the laser processing device 1 according to the present embodiment, the modulation pattern may include elliptical patterns Es, Ew for making the beam shape of the focused spot C in the XY plane including the X and Y directions into an elliptical shape with the X direction as the longitudinal direction. In this case, the control unit 6 may perform a fourth pattern control for making the beam shape of the focused spot C into an inclined shape by making the spatial light modulator 7 display the modulation pattern so that the intensity of the elliptical patterns Es, Ew is asymmetric with respect to the axis Ax along the X direction in the second formation process. According to the knowledge of the present inventor, even in this case, the beam shape of the focused spot C in the YZ plane E can be formed into an arc shape, and an oblique crack inclined in the shift direction can be formed.

[0096] Furthermore, in the laser processing apparatus 1 according to this embodiment, the control unit 6 may perform a fifth pattern control in the second formation process to make the beam shape of the focused spot C including the multiple focused points CI an inclined shape by causing the spatial light modulator 7 to display a modulation pattern for forming multiple focused points CI arranged along the shift direction in the YZ plane E. According to the knowledge of the present inventor, in this case as well, it is possible to form an oblique crack inclined in the shift direction.

[0097] In addition, in the laser processing device 1 according to this embodiment, the control unit 6 may perform the first formation process on one line Aa1 set on the target 11 along the X direction, and then perform the second formation process. In this way, even when the first formation process and the second formation process are performed separately, it is possible to form an oblique crack. Furthermore, in the laser processing device 1, the control unit 6 may simultaneously perform the first formation process and the second formation process on one line Aa1 set on the target 11 by causing the spatial light modulator 7 to display a modulation pattern including a branching pattern for branching the laser light L. In this way, it is possible to form an oblique crack even when the first formation process and the second formation process are performed simultaneously. [Second embodiment]

[0098] Next, a method for manufacturing a semiconductor member and a laser processing device according to the second embodiment will be described. First, an outline will be described. FIG. 24 is a diagram showing an object according to the second embodiment. FIG. 24(a) is a plan view, and FIG. 24(b) is a cross-sectional view taken along line XXIb-XXIb in FIG. 24(a). The object 11 shown in FIG. 24 includes, for example, a semiconductor. The object 11 is, for example, a semiconductor wafer (for example, a silicon wafer). The object 11 includes a first surface 11a and a second surface 11b opposite to the first surface 11a. The object 11 also includes a first region 11A including the first surface 11a and a second region 11B including the second surface 11b.

[0099] In addition, the line G in the figure is a virtual line indicating the boundary between the first region 11A and the second region 11B. The first region 11A is a region to be ground along the first surface 11a. Here, a circular semiconductor member 60 is cut out from the target object 11 (second region 11B). For this purpose, a plurality of lines Ac extending in a circular shape when viewed from the Z direction are set as lines to be cut on the target object 11. The lines Ac are, for example, virtual lines.

[0100] As an example, the target object 11 is supported by the stage 2 so that the first surface 11a faces the condenser lens 33. In this embodiment, the target object 11 is irradiated with laser light L while moving a focused spot C of the laser light L relatively along each of the lines Ac, to form modified regions 12 and cracks 13 along each of the lines A. At this time, the focused spot C is moved relatively in the X direction. That is, the X direction is set as the processing progress direction here. In this embodiment, a crack 13 inclined in the Y direction with respect to the Z direction is formed in an intersecting plane (YZ plane E) that intersects (is perpendicular to) the X direction, which is the processing progress direction.

[0101] In FIG. 24(b), the extension direction of the desired crack 13 is indicated by line D. The adjacent lines D in the YZ plane E are inclined so as to move away from each other from the second surface 11b toward the first surface 11a. In other words, in this embodiment, the cracks 13 adjacent to each other in the Y direction in the YZ plane E are formed obliquely so as to move away from each other from the second surface 11b toward the first surface 11a. In further other words, in this embodiment, the cracks 13 are formed in the YZ plane E inclined with respect to the Z direction so as to move away from the reference line Az (along the Z direction) passing through the center of the line Ac from the second surface 11b toward the first surface 11a.

[0102] The inclination direction of the cracks may be reversed. That is, the lines D adjacent to each other in the YZ plane E may be inclined so as to approach each other from the second surface 11b to the first surface 11a. In other words, the cracks 13 adjacent to each other in the Y direction in the YZ plane E may be formed obliquely so as to approach each other from the second surface 11b to the first surface 11a. In other words, the cracks 13 inclined with respect to the Z direction may be formed so as to approach the reference line Az (along the Z direction) passing through the center of the line Ac from the second surface 11b to the first surface 11a in the YZ plane E. These variations in the inclination direction may be arbitrarily selected according to requirements such as the shape, use, and division method of the semiconductor member obtained. For example, as described later (as shown in (c) of FIG. 26), the inclination direction may be appropriately selected in a case where the obtained semiconductor member 60 is picked up from the first surface 11a (first surface 60a) side and a case where the obtained semiconductor member 60 is picked up from the second surface 11b (second surface 60b) side.

[0103] Next, the manufacturing method of the semiconductor member and the laser processing device according to the present embodiment will be specifically described. In this method, first, the object 11 as described above is prepared, and the object 11 is supported by the stage 2 so that the first surface 11a faces the condenser lens 33. In this state, first, a laser processing step is performed in which a condensed spot C (condensed spots C1, C2) of the laser light L (laser light L1, L2) is formed on the object 11 along one line Ac, and the condensed spot C is moved relative to the object 11 along the line Ac to form the modified region 12 and the crack 13 extending from the modified region 12 in the object 11 along the line Ac.

[0104] More specifically, in the laser processing step, as shown in Fig. 25, the position of the focused spot C1 in the Z direction intersecting with the first surface 11a, which is the incident surface of the laser light L1 in the object 11, is set to a first Z position Z1, while the focused spot C1 is relatively moved along a line Aa1 to perform a first forming step of forming the modified region 12a and the crack 13a extending from the modified region 12a in the object 11. The first Z position Z1 is set in the first region 11A, which is the region to be ground. In the first forming step, the position of the focused spot C1 in the Y direction, which is along the first surface 11a and intersects with the X direction, is set to a first Y position Y1.

[0105] In addition, in the laser processing step, the position of the focal spot C2 of the laser light L2 in the Z direction is set to a second Z position Z2 closer to the first surface 11a (incident surface) than the first Z position Z1 of the focal spot C1 in the first formation step, while the focal spot C2 is relatively moved along the line Ac in the X direction to form the modified region 12b and the crack 13b extending from the modified region 12b. The second Z position Z2 is set in the first region 11A, which is the region to be ground. In the second formation step, the position of the focal spot C2 in the Y direction is set to a second Y position Y2 shifted from the first Y position Y1 of the focal spot C1. In addition, in the second formation step, the laser light L2 is modulated so that the beam shape of the focal spot C2 in the YZ plane E becomes an inclined shape that is inclined in the direction of the shift at least on the first surface 11a side from the center of the focal spot C2. As a result, the crack 13b is formed in the YZ plane E so as to be inclined in the direction of the shift.

[0106] In the first forming step, as in the second forming step, the laser light L1 is modulated so that the beam shape of the focused spot C1 in the YZ plane E is inclined in the direction of the shift at least on the first surface 11a side from the center of the focused spot C1. As a result, the crack 13a and the crack 13b are connected to each other, and a crack 13 is formed that extends obliquely across the modified regions 12a and 12b. In the illustrated example, the crack 13 reaches the first surface 11a and the second surface 11b of the object 11, but it is not necessary that the crack 13 reach the first surface 11a and the second surface 11b of the object 11.

[0107] The laser processing steps including the first and second forming steps can be performed, for example, as in the first embodiment, by the control unit 6 of the laser processing apparatus 1 controlling each unit of the laser processing apparatus 1. That is, in the laser processing apparatus 1 according to this embodiment, the control unit 6 controls the spatial light modulator 7 and the driving units 4 and 5 to perform a first forming process in which the position of the light-focusing spot C1 in the Z direction is set to a first Z position Z1, and the light-focusing spot C1 is relatively moved along the line Ac to form the modified region 12a and the crack 13a in the target object 11, and a second forming process in which the position of the light-focusing spot C2 in the Z direction is set to a second Z position Z2 on the first surface 11a side from the first Z position Z1, and the light-focusing spot C2 is relatively moved along the line Ac to form the modified region 12b and the crack 13b.

[0108] In the first formation process, the control unit 6 sets the position of the focused spot C1 in the Y direction to the first Y position Y1. In the second formation process, the control unit 6 sets the position of the focused spot C2 in the Y direction to the second Y position Y2 shifted from the first Y position Y1, and modulates the laser light L2 by controlling the modulation pattern displayed by the spatial light modulator 7 so that the beam shape of the focused spot C2 in the YZ plane E becomes an inclined shape that is inclined in the direction of the shift at least on the first surface 11a side from the center of the focused spot C2. Here, the control unit 6 similarly modulates the laser light L1 so that the beam shape of the focused spot C1 in the YZ plane E becomes an inclined shape that is inclined in the direction of the shift at least on the first surface 11a side from the center of the focused spot C1. The modulation pattern for making the beam shape into an inclined shape is as described above.

[0109] The first forming step (first forming process) and the second forming step (second forming process) may be performed simultaneously (multifocal processing) or sequentially (single-pass processing). That is, the control unit 6 may perform the first forming process on one line Ac and then the second forming process. Alternatively, the control unit 6 may perform the first forming process and the second forming process simultaneously on one line Ac set on the target 11 by causing the spatial light modulator 7 to display a modulation pattern including a branching pattern for branching the laser light L into laser light L1 and L2.

[0110] Furthermore, in order to relatively move the focused spots C1 and C2 in the X direction, for example, in a state in which the focused spots C1 and C2 are positioned on the line Ac when viewed from the Z direction, the control unit 6 may control the drive unit 4 to move the stage 2 two-dimensionally so that the focused spots C1 and C2 move along the circular line Ac. Alternatively, the control unit 6 may control the drive unit 5 to move the laser irradiation unit 3, or the control unit 6 may control the stage 2 to rotate, or the control unit 6 may perform a combination of these controls so that the focused spots C1 and C2 move along the line Ac.

[0111] In this way, when processing is performed by relatively moving the focused spots C1 and C2 along the circular line Ac, the focused spots C1 and C2 can be controlled to rotate so that the focused spots C1 and C2 are elongated in the XY plane and their longitudinal directions are inclined with respect to the X direction, which is the processing proceeding direction. As an example, the focused spots C1 and C2 can be rotated so that the angle between the longitudinal direction and the X direction in the XY plane becomes a first angle (+10° to +35°), and can also be rotated so that the angle becomes a second angle (-35° to -10°). The first angle or the second angle can be selected depending on the relationship between the line Ac and the crystal orientation of the object 11. In this case, in the spatial light modulator 7, the modulation pattern for making the beam shape in the YZ plane an inclined shape and the pattern for making the beam shape in the XY plane an elongated shape are superimposed as described above.

[0112] In the method for manufacturing a semiconductor member according to this embodiment, the above-mentioned laser processing step is performed on all of the lines Ac. As a result, modified regions 12 and cracks 13 are formed along all of the lines Ac. That is, in this laser processing step, the focused spot C is moved relatively along each of the multiple lines Ac, thereby forming modified regions 12 and cracks 13 along each of the multiple lines Ac.

[0113] Thereafter, in the method for producing a semiconductor member according to the present embodiment, a separation step is performed in which a semiconductor member 60 is formed from the object 11 by separating a part of the object 11. More specifically, before the separation step, a grinding step is performed in which the object 11 is ground from the first surface 11a side to remove the first region 11A, as shown in (a) and (b) of FIG. 26. This removes the first region 11A as well as the modified region 12 and a part of the crack 13. In addition, a new first surface 11c (surface of the remaining second region 11B) is formed on the side opposite to the second surface 11b. That is, here, between the laser processing step and the separation step, a grinding step is performed in which the object 11 is ground along the Z direction to remove the modified region 12 from the object 11.

[0114] Then, as shown in FIG. 26(c), a force is applied to the part (corresponding to the semiconductor member 60) to be separated from the second surface 11b side, and the part is separated from the second region 11B while holding the outer surface (corresponding to the outer surface 60s of the semiconductor member 60) of the part with a jig. This forms the semiconductor member 60. The semiconductor member 60 includes a first surface 60a that is a part of the new first surface 11c, and a second surface 60b that is a part of the second surface 11b. The outer surface 60s is a surface that connects the first surface 60a and the second surface 60b, and is an inclined surface defined by the crack 13. The outer surface 60s is inclined with respect to the normal to the first surface 60a and the second surface 60b.

[0115] Note that the grinding step may be performed after the separation step. That is, after the separation step, a grinding step may be performed in which the semiconductor member 60 is ground along the Z direction to remove the modified region 12 from the semiconductor member 60.

[0116] The above-described method for manufacturing a semiconductor member includes the laser processing method according to the present embodiment. The laser processing method according to the present embodiment includes the above-described laser processing step.

[0117] In this embodiment, it is also possible to manufacture members having a shape different from that of the semiconductor member 60, such as a semiconductor member 60A shown in Fig. 27(a) and a semiconductor member 60B shown in Fig. 27(b). Next, an example of manufacturing these semiconductor members 60A and 60B will be described.

[0118] The semiconductor member 60A includes a first surface 60a, a second surface 60b, and an outer surface 60s, similar to the semiconductor member 60. Furthermore, the semiconductor member 60A includes an outer surface 60r. The outer surface 60r is parallel to the normals of the first surface 60a and the second surface 60b. The outer surface 60s is connected to the second surface 60b, and the outer surface 60r is connected to the first surface 60a. As a result, the outer surfaces 60s and 60r connect the first surface 60a and the second surface 60b.

[0119] When manufacturing such a semiconductor member 60A, as shown in FIG. 28, in addition to forming the modified region 12 and the crack 13 described above, the modified region 14 and the crack 15 extending from the modified region 14 along the Z direction are further formed in the object 11. That is, when forming the semiconductor member 60A, the laser processing step includes a first processing step for forming the modified region 12 and the crack 13, and a second processing step for forming the modified region 14 and the crack 15. The first processing step is as described above. That is, in the first processing step, the focused spot C is moved relative to the object 11 along the line Ac to form the modified region 12 in the object 11 along the line Ac, and the crack 13 extending from the modified region 12 is formed. The crack 13 is inclined with respect to the Z direction so as to move away from the reference line Az (along the Z direction) passing through the center of the line Ac as it approaches the first surface 11a in the YZ plane E. In the illustrated example, the modified region 12 further includes another modified region 12c interposed between the modified region 12a and the modified region 12b.

[0120] Meanwhile, in the second processing step, the focused spot of the laser light is moved along the line Ac relative to the object 11 to form a modified region 14 closer to the first surface 11a than the crack 13, and also form a crack 15 extending from the modified region 14 along the Z direction toward the crack 13 and the first surface 11a in the YZ plane E. Here, one end of the crack 15 reaches the crack 13, and the other end of the crack 15 reaches the first surface 11a. Also, here, two modified regions 14 aligned in the Z direction are formed. In FIG. 28(a), the extension direction of the desired crack 15 (here, the Z direction) is indicated by line K.

[0121] In the state where the modified regions 12, 14 and the cracks 13, 15 are formed as described above, a grinding step and a separation step are performed to separate a part of the object 11 at the boundaries of the cracks 13, 15, and obtain a semiconductor member 60A. The crack 13 defines an outer side surface 60s of the semiconductor member 60A, and the crack 15 defines an outer side surface 60r of the semiconductor member 60A. Note that in the first processing step, the crack 13 may be formed so as to be inclined with respect to the Z direction so as to approach from a reference line Az (along the Z direction) passing through the center of the line Ac as it approaches the first surface 11a in the YZ plane E.

[0122] The semiconductor member 60B shown in FIG. 27(b) includes a first surface 60a, a second surface 60b, an outer surface 60s, and an outer surface 60r, similar to the semiconductor member 60A. Furthermore, the semiconductor member 60B includes an outer surface 60m. The outer surface 60m is an inclined surface inclined with respect to the normal line of the first surface 60a and the second surface 60b. The inclination direction of the outer surface 60m is opposite to the inclination direction of the outer surface 60s. In the semiconductor member 60B, the outer surface 60s is connected to the second surface 60b, the outer surface 60m is connected to the first surface 60a, and the outer surface 60r is connected to the outer surface 60s and the outer surface 60m. As a result, the outer surfaces 60s, 60r, and 60m connect the first surface 60a and the second surface 60b.

[0123] 29, in addition to forming the modified regions 12, 14 and the cracks 13, 15 described above, a modified region 16 and a crack 17 extending obliquely from the modified region 16 are further formed in the object 11. That is, in forming the semiconductor member 60B, the laser processing step further includes a third processing step for forming the modified region 16 and the crack 17, in addition to a first processing step for forming the modified region 12 and the crack 13 and a second processing step for forming the modified region 14 and the crack 15.

[0124] The first and second processing steps are as described above. Meanwhile, in the third processing step, the focused spot of the laser light is moved relative to the object 11 along the line Ac to form the modified region 16 on the first surface 11a side of the intersection between the crack 13 and the crack 15, and form the crack 17 extending from the modified region 16 to the crack 15. The crack 17 is inclined with respect to the Z direction in the YZ plane E so as to approach the reference line Az as it approaches the first surface 11a. Thus, the direction of inclination of the crack 17 in the YZ plane E is opposite to the direction of inclination of the crack 13. Here, one end of the crack 17 reaches the crack 15, and the other end of the crack 17 reaches the first surface 11a. Here, two modified regions 16 are formed side by side in the YZ plane E. In addition, in FIG. 29(a), the extension direction of the desired crack 17 is indicated by the line K.

[0125] In a state in which the modified regions 12, 14, 16 and the cracks 13, 15, 17 are formed as described above, a grinding step and a separation step are performed to separate a part of the object 11 at the boundaries of the cracks 13, 15, 17, thereby obtaining the semiconductor member 60B. The crack 13 defines the outer surface 60s of the semiconductor member 60B, the crack 15 defines the outer surface 60r of the semiconductor member 60B, and the crack 17 defines the outer surface 60m of the semiconductor member 60B.

[0126] In addition, the part of the object 11 corresponding to the semiconductor material 60B has a shape in which the diameter is relatively large toward the center in the Z direction. Therefore, in the separation process, it is difficult to extract the part corresponding to the semiconductor material 60B from the object 11 while maintaining the shape of the object 11. Therefore, in this case, processing is required to cut the object 11 into a plurality of parts before the separation process. For this purpose, as shown in (a) of FIG. 30, lines As are set so as to extend from each line Ac to the outer edge of the object 11 when viewed in the Z direction.

[0127] The lines As are connected to the lines Ac so that the target object 11 is divided into a plurality of parts by the lines As and the lines Ac when viewed from the Z direction. Then, modified regions and cracks are formed along the lines As before the separation step. As a result, in the separation step, the target object 11 is cut at the modified regions and cracks formed along the lines As as boundaries, and the semiconductor member 60B can be easily separated from the target object 11.

[0128] In the above example, the grinding step is described, but the grinding step is not essential. For example, in the YZ plane, the modified regions 12, 14, 16 are arranged in the Z direction so as to cover the entire Z direction of the object 11, and the cracks 13, 15, 17 are formed so as to cover the modified regions 12, 14, 16. Then, by applying an external force, the object 11 is divided at the modified regions 12, 14, 16 and the cracks 13, 15, 17 as boundaries to obtain the semiconductor member 60B. The obtained semiconductor member 60B includes the modified regions (parts of the modified regions 12, 14, 16) exposed on the outer surfaces 60s, 60r, 60m. In this case, the modified regions exposed on the outer surfaces 60s, 60r, 60m may be removed by etching the semiconductor member 60B.

[0129] As described above, in the semiconductor component manufacturing method (laser processing method) and the laser processing apparatus 1 according to this embodiment, similarly to the first embodiment, the focused spot C2 is shifted in the Y direction and the beam shape of the focused spot C2 is controlled, so that at least the crack 13b can be an oblique crack inclined in the shift direction within the YZ plane E. That is, an oblique crack can be formed.

[0130] In addition, in the manufacturing method of the semiconductor member according to the present embodiment, the focused spot C of the laser light L is moved relative to the target 11 along the line Ac extending in a circular shape, thereby forming the modified region 12 and the crack 13 in the target 11 along the line Ac. At this time, the crack 13 inclined with respect to the Z direction is formed in the intersecting plane (YZ plane E) intersecting the line Ac. Then, the semiconductor member 60 is formed by separating a part of the target 11 with the crack 13 as a boundary. In this way, the semiconductor member 60 including the inclined surface defined by the crack 13 as the outer side surface 60s is obtained. The inclined outer side surface 60s can be used as a bevel for holding the semiconductor member 60 while protecting (without touching) the front and back surfaces (first surface 60a and second surface 60b) of the semiconductor member 60 during transportation of the semiconductor member 60. In this way, according to the manufacturing method of the semiconductor member according to the present embodiment, the semiconductor member 60 having a bevel can be formed by laser processing.

[0131] Furthermore, in the method for manufacturing a semiconductor member according to this embodiment, a plurality of lines Ac are set on the object 11, and in the laser processing step, the focused spot C is moved relatively along each of the plurality of lines Ac to form modified regions 12 and cracks 13 along each of the plurality of lines Ac. Then, in the separation step, a portion of the object 11 is separated along each of the plurality of lines Ac to form a plurality of semiconductor members 60 from the object 11. In this way, even when a plurality of semiconductor members 60 are manufactured from a single object 11, it is possible to form a bevel on each of the semiconductor members 60.

[0132] Furthermore, in the method for manufacturing a semiconductor member according to this embodiment, the laser processing step may include a second processing step in which the focused spot is moved along the line Ac relative to the target object 11 to form a modified region 14 closer to the first surface 11a than the crack 13, and a crack 15 extending from the modified region 14 toward the crack 13. Furthermore, in the first processing step, a crack 13 inclined with respect to the Z direction so as to move away from the reference line Az passing through the center of the line Ac toward the first surface 11a may be formed in the YZ surface E, and in the second processing step, a crack 15 extending along the Z direction may be formed in the YZ surface E. In this case, a semiconductor member 60A including an inclined surface (outer surface 60s) defined by the crack 13 and a vertical surface (outer surface 60r) defined by the crack 15 can be formed.

[0133] Furthermore, in the manufacturing method of the semiconductor member according to this embodiment, the laser processing step may include a third processing step of forming a modified region 16 on the first surface 11a side of the intersection point between the crack 13 and the crack 15 and forming a crack 17 extending from the modified region 16 toward the crack 15 by moving the focused spot along the line Ac relative to the target object 11. In the third processing step, the crack 17 may be formed in the YZ plane E, inclined with respect to the Z direction so as to approach the reference line Az toward the first surface 11a. In this case, it is possible to form a semiconductor member 60B including an inclined surface (outer surface 60s) defined by the crack 13, a vertical surface (outer surface 60r) defined by the crack 15, and another inclined surface (outer surface 60m) defined by the crack 17.

[0134] In the method for manufacturing a semiconductor member according to this embodiment, the laser processing step includes a second processing step in which the focused spot is moved along the line Ac relative to the target object 11 to form a modified region 14 closer to the first surface 11a than the crack 13, and a crack 15 extending from the modified region 14 toward the crack 13. In the first processing step, the crack 13 may be formed in the YZ surface E so as to approach the reference line Az toward the first surface 11a, and in the second processing step, the crack 15 may be formed in the YZ surface E to extend along the Z direction. In this case, a semiconductor member 60A can be formed that includes, as outer surfaces, an inclined surface (outer surface 60s) defined by the crack 13 and a vertical surface (outer surface 60r) defined by the crack 15.

[0135] Furthermore, the method for producing a semiconductor member according to this embodiment may further include a grinding step between the laser processing step and the separating step, in which the object 11 is ground along the Z direction to remove the modified region 12 and the like from the object 11. Alternatively, the method for producing a semiconductor member according to this embodiment may further include a grinding step after the separating step, in which the semiconductor member 60 is ground along the Z direction to remove the modified region 12 and the like from the semiconductor member 60. In this case, it is possible to obtain a semiconductor member 60 from which the modified region 12 has been removed.

[0136] As shown in FIG. 30(b), a single (circular) line Ac may be set on the object 11. Here, the outer shape of the object 11 is circular when viewed from the Z direction. Moreover, the line Ac has a smaller diameter than the outer shape of the object 11 when viewed from the Z direction. Moreover, the line Ac is set on the object 11 so as to be concentric with the outer shape of the object 11 when viewed from the Z direction. In this case, in the laser processing step, the modified regions 12, 14, 16 and the cracks 13, 15, 17 can be formed along the line Ac by relatively moving the focused spot along the line Ac. Then, in the separation step, a part of the object 11 may be separated along the line Ac to form one semiconductor member 60 from the object 11. In this way, even when one semiconductor member 60 is manufactured from one object 11, a bevel can be formed on the semiconductor member 60. [Third embodiment]

[0137] Next, a method for manufacturing a semiconductor member and a laser processing device according to the third embodiment will be described. First, an overview will be described. FIG. 31 is a diagram showing an object according to the third embodiment. FIG. 31(a) is a plan view, and FIG. 31(b) is a cross-sectional view taken along the line XXXb-XXXb in FIG. 31(a). The object 11 shown in FIG. 31 includes, for example, a semiconductor. One example of the object 11 is a semiconductor wafer (for example, a silicon wafer). The object 11 includes a first surface 11a and a second surface 11b opposite to the first surface 11a.

[0138] A plurality of lines A parallel to the first surface 11a and the second surface 11b are set as lines to be cut on the object 11. The lines A may be set in a lattice pattern, but here, a plurality of lines A extending parallel to each other in one direction are illustrated. The lines A are, for example, virtual lines. The object 11 includes a first region 11A including the first surface 11a and a second region 11B including the second surface 11b. Note that the line G in the figure is a virtual line indicating the boundary between the first region 11A and the second region 11B. The first region 11A is a region to be ground.

[0139] The object 11 also includes a semiconductor structure N formed on the second surface 11b. The semiconductor structure N has a structure for making each semiconductor member obtained by cutting the object 11 along the line A function as a semiconductor element. Therefore, the line A is set to pass between the semiconductor structure portions N. The object 11 is held by a holding member T on the second surface 11b side and supported by the stage 2 so that the first surface 11a faces the condenser lens 33 side. The holding member T is, for example, a stretchable tape.

[0140] In this embodiment, the laser light L is irradiated onto such an object 11 while moving a focused spot C of the laser light L relatively along each of the lines A, to form modified regions 12 and cracks 13 along each of the lines A. At this time, the focused spot C is moved relatively in the X direction. That is, the X direction is the processing progress direction here. In this embodiment, the cracks 13 including a portion inclined in the Y direction with respect to the Z direction are formed within an intersecting plane (YZ plane E) that intersects (is perpendicular to) the X direction, which is the processing progress direction.

[0141] Next, the manufacturing method of the semiconductor member and the laser processing device according to this embodiment will be specifically described. As shown in Fig. 32, in this method, first, the object 11 as described above is prepared, and the object 11 is supported by the stage 2 so that the first surface 11a faces the condenser lens 33 side and the line A is along the X direction. In this state, first, a condensed spot C of the laser light L (condensed spots C1, C2, C3 of the laser light L1, L2, L3) is formed on the object 11 for one line A, and the condensed spot C is moved relatively to the object 11, thereby performing a laser processing step to perform laser processing of the object 11.

[0142] More specifically, in the laser processing step, a first formation step is performed in which the position of the focal spot C1 in the Z direction intersecting with the first surface 11a, which is the incident surface of the laser light L on the object 11, is set to a first Z position Z1, and the focal spot C1 is moved relatively along a line A extending in the X direction along the first surface 11a to form a modified region (first modified region) 12a and a crack (first crack) 13a extending from the modified region 12a in the object 11, and the position of the focal spot C3 in the Z direction is set to the first Z position Z3, and the focal spot C3 is moved relatively along the line A to form a modified region (first modified region) 12c and a crack (first crack) 13c extending from the modified region 12c in the object 11.

[0143] The first Z position Z3 is a position closer to the first surface 11a than the first Z position Z1. Here, the first Z position Z1 is set in the second region 11B, and the first Z position Z3 is set in the first region 11A, which is the region to be ground. However, one of the first Z positions Z1 and Z3 may be set in the first region 11A or in the second region 11B, and may be arbitrarily set according to the requirement of whether or not the modified regions 12a and 12c are to remain after the target object 11 is ground.

[0144] Thus, in the first forming step, in the present embodiment, the focused spots C1, C3 are formed at the first Z positions Z1, Z3 that are different from each other in the Z direction, and are moved relative to each other to form the modified regions 12a, 12c arranged in the Z direction in the intersecting plane (YZ plane E) that intersects with the line A, and the cracks 13a, 13c are formed so as to extend across the modified regions 12a, 12c. In the first forming step, the positions of the focused spots C1, C3 in the Y direction are set to the first Y position Y1, and the cracks 13a, 13c are formed so as to extend along the Z direction in the YZ plane E and reach the second surface 11b. These cracks 13a, 13c are, for example, along the main cleavage plane of the object 11.

[0145] 33, in the laser forming process, after the first forming process, the position of the focal spot C2 in the Z direction of the laser light L2 is set to a second Z position Z2 closer to the first surface 11a than the first Z position Z3, and the focal spot C2 is moved relatively along the line A to form the modified region (second modified region) 12b and the crack (second crack) 13b extending from the modified region 12b. Here, since the first Z position Z3 is set in the first region 11A, which is the region to be ground, as described above, the second Z position Z2 is also set in the first region 11A. In particular, the second Z position Z2 is set so that the crack 13b is formed in the first region 11A.

[0146] In the second formation step, the position of the focused spot C2 in the Y direction is set to a second Y position Y2 shifted from the first Y position Y1 of the focused spots C1 and C3, and the crack 13b is formed so as to be inclined with respect to the Z direction in the YZ plane E. More specifically, in the second formation step, the laser light L2 is modulated so that the beam shape of the focused spot C2 in the YZ plane E is inclined in the direction of the shift at least on the first surface 11a side from the center of the focused spot C2, thereby forming the crack 13b inclined with respect to the shift direction in the YZ plane E. Furthermore, in the second formation step, the crack 13b is formed so as to be inclined with respect to the cleavage plane of the object 11 in the YZ plane E.

[0147] The laser processing steps including the first and second forming steps can be performed, for example, as in the first embodiment, by the control unit 6 of the laser processing device 1 controlling each unit of the laser processing device 1. That is, in the laser processing device 1 according to this embodiment, the control unit 6 controls the spatial light modulator 7 and the driving units 4 and 5 to perform a first forming process in which the positions of the focused spots C1 and C3 in the Z direction are set to the first Z positions Z1 and Z3, and the focused spots C1 and C3 are relatively moved along the line A to form the modified regions 12a and 12c and the cracks 13a and 13c in the object 11, and a second forming process in which the position of the focused spot C2 in the Z direction is set to the second Z position Z2 on the first surface 11a side from the first Z positions Z1 and Z3, and the focused spot C2 is relatively moved along the line A to form the modified regions 12b and the cracks 13b.

[0148] In the first forming process, the control unit 6 sets the positions of the focused spots C1 and C3 in the Y direction to the first Y position Y1. In the second forming process, the control unit 6 sets the position of the focused spot C2 in the Y direction to the second Y position Y2 shifted from the first Y position Y1, and modulates the laser light L2 by controlling the modulation pattern displayed on the spatial light modulator 7 so that the beam shape of the focused spot C2 in the YZ plane E becomes an inclined shape that is inclined in the direction of the shift at least on the first surface 11a side from the center of the focused spot C2. The modulation pattern for making the beam shape into an inclined shape is as described above. In the first forming step (first forming process), the formation of the modified region 12a and the crack 13a by the laser light L1 and the formation of the modified region 12c and the crack 13c by the laser light L3 may be performed simultaneously (multifocal processing) or sequentially (single-pass processing).

[0149] Furthermore, by displaying a modulation pattern including a branching pattern for branching the laser light L into laser lights L1, L2, and L3 on the spatial light modulator 7, the first forming step (first forming process) and the second forming step (second forming process) may be performed simultaneously for one line A set on the target 11. In this case, by synthesizing the modulation pattern so as to generate coma aberration only for the laser light L2 out of the laser lights L1, L2, and L3, it is possible to make only the focused spot C2 out of the focused spots C1, C2, and C3 have an inclined shape.

[0150] In the method for manufacturing a semiconductor member according to this embodiment, the above laser processing step is performed on all of the lines A. As a result, as shown in (a) of Fig. 34, modified regions 12 and cracks 13 are formed along all of the lines A. Note that cracks 13b and cracks 13c may or may not be connected to each other.

[0151] Thereafter, in the method for manufacturing a semiconductor component according to the present embodiment, as shown in (b) of Fig. 34, the object 11 is ground from the first surface 11a side to remove the first region 11A, thereby removing at least the crack 13b extending obliquely with respect to the Z direction from the object 11. Here, in addition to the crack 13b, the modified regions 12b and 12c are also removed.

[0152] As a result, the semiconductor member 70 is obtained as the remaining second region 11B. The semiconductor member 70 includes the second surface 11b and a new first surface 70a that is the surface opposite to the second surface 11b and is formed by grinding. A crack 13 is formed in the semiconductor member 70, which extends from at least the new first surface 70a to the second surface 11b (here, the modified region 12a remains). Therefore, in the subsequent step, by expanding the holding member T, it is possible to separate the semiconductor member 70 into a plurality of separate semiconductor members with the crack 13 as a boundary. The above-mentioned method for manufacturing a semiconductor member includes the laser processing method according to this embodiment. The laser processing method according to this embodiment includes the above-mentioned laser processing step.

[0153] As described above, in the semiconductor component manufacturing method (laser processing method) and the laser processing apparatus 1 according to this embodiment, similarly to the first embodiment, the focused spot C2 is shifted in the Y direction and the beam shape of the focused spot C2 is controlled, so that at least the crack 13b can be an oblique crack inclined in the shift direction within the YZ plane E. That is, an oblique crack can be formed.

[0154] In the laser processing method according to this embodiment, in the first forming step, the focused spots C1 and C3 of the laser beams L1 and L3 are moved relatively along a line A along the X direction to form the modified regions 12a and 12c in the object 11, and the cracks 13a and 13c extending from the modified regions 12a and 12c are formed in the object 11 so as to reach the second surface 11b of the object 11. At this time, the positions of the focused spots C1 and C3 in the Z direction are defined as first Z positions Z1 and Z3. At this time, the cracks 13a and 13c are formed along the Z direction in the YZ plane E intersecting the X direction.

[0155] Then, in the second forming step, the Z-direction position of the focused spot C2 of the laser light L2 is set to a second Z-position Z2 closer to the first surface 11a than the first Z-positions Z1 and Z3, while the focused spot C2 is relatively moved along the line A to form the modified region 12b and the crack 13b in the object 11. At this time, the Y-direction position of the focused spot C2 is shifted in the Y-direction compared to the first forming step, and the crack 13b is formed so as to be inclined with respect to the Z-direction in the YZ plane E. According to the knowledge of the inventor, by doing this, when the crack 13c tries to extend along the Z-direction toward the first surface 11a, it is connected to the crack 13b and the extension is stopped. Therefore, according to this method, it is possible to suppress the extension of the crack 13.

[0156] In the laser processing method according to this embodiment, the target object 11 has a region to be ground (first region 11A) including the first surface 11a, and in the first forming step, the first Z position Z1 is set closer to the second surface 11b than the region to be ground. In the second forming step, the second Z position Z2 is set so that the crack 13b is formed inside the region to be ground. Therefore, the crack 13b is removed by grinding the region to be ground, thereby reducing the effect of the inclined crack.

[0157] Furthermore, in the laser processing method according to this embodiment, in the second formation step, the crack 13b is formed in the YZ plane E so as to be inclined with respect to the cleavage plane of the object 11. In this case, it is possible to more reliably suppress the propagation of the crack.

[0158] In the laser processing method according to the present embodiment, in the first forming step, focused spots C1, C3 are formed at a plurality of first Z positions Z1, Z3 that are different from each other in the Z direction and then moved relatively to form a plurality of modified regions 12a, 12c arranged in the Z direction in the YZ plane E, and also form cracks 13a, 13c so as to span the plurality of modified regions 12a, 12c. Therefore, by forming cracks 13a, 13c that are longer in the Z direction, a thicker object 11 can be suitably processed.

[0159] In the laser processing method according to the present embodiment, the crack 13a may be formed in the first formation step so as to reach the second surface 11b. In this way, when the crack 13a reaches the second surface 11b, the crack is likely to grow unintentionally, so it is more effective to suppress the growth of the crack.

[0160] Furthermore, in the laser processing method according to this embodiment, the first forming step and the second forming step may be performed simultaneously on one line A set on the target object 11 by branching the laser light L. In this way, even when the first forming step and the second forming step are performed simultaneously, it is possible to form an oblique crack.

[0161] Furthermore, the method for producing a semiconductor member according to this embodiment is a method for producing a semiconductor member 70 from an object 11 containing a semiconductor, and after carrying out the laser processing step included in the laser processing method described above, the object 11 is ground from the first surface 11a side to remove at least the crack 13b from the object 11, thereby forming the semiconductor member 70 from the object 11. In this production method, the laser processing step of the laser processing method described above is carried out. Therefore, unintended crack propagation is suppressed. Therefore, when the object is ground after the laser processing step, the occurrence of chipping is suppressed. In addition, transportation to the place where grinding is performed is facilitated.

[0162] In the above example, the case where the crack 13a is formed so as to reach the second surface 11b in the first forming step has been described. However, the crack 13a does not have to reach the second surface 11b. In this case, the crack 13a may extend toward the second surface 11b and reach the second surface 11b by forming the modified region 12b and the crack 13b in the second forming step, or the crack 13a may extend toward the second surface 11b and reach the second surface 11b by grinding the object 11 in the grinding step.

[0163] In the above example, the modified region 12b, which is the starting point of the crack 13b extending obliquely with respect to the Z direction, is located closer to the first surface 11a, which is the incident surface of the laser light L, than the modified regions 12a and 12c, which are the starting points of the cracks 13a and 13c extending along the Z direction. However, the modified region 12b and the crack 13b may be located closer to the second surface 11b than the modified regions 12a and 12c and the cracks 13a and 13c. That is, in the second forming step, the second Z position Z2 can also be set closer to the second surface 11b than the first Z position Z1. In this case, the beam shape of the focused spot C2 in the YZ plane is controlled to be inclined in the direction from the second Y position Y2 of the focused spot C2 to the first Y position Y1 of the focused spot C1 at least on the first surface 11a side of the center Ca, thereby forming the crack 13b inclined in that direction with respect to the Z direction.

[0164] The above embodiment describes one aspect of the present disclosure. Therefore, one aspect of the present disclosure is not limited to the above embodiment and may be modified as desired.

[0165] For example, the number of modified regions 12 formed side by side in the Z direction in the YZ plane E can be set arbitrarily depending on the thickness of the object 11, the desired extension amount of the crack 13, and the like.

[0166] Furthermore, the modulation pattern for modulating the laser light L is not limited to the above example, and any pattern that can make the beam shape of the focused spot C into an inclined shape can be adopted.

[0167] In addition, the above-mentioned embodiments may be applied in any combination with each other or by exchanging parts with each other. For example, when the modified region 12 and the crack 13 are formed along the circular line Ac as in the second embodiment, a configuration for suppressing the extension of the crack 13 may be adopted as in the third embodiment.

[0168] Furthermore, in the above embodiment, an example was given in which the object 11 was held via a holding member T such as tape, but the object 11 may be held by bonding, for example, a silicon substrate or a glass substrate. When a circuit or the like is formed on one surface of the object 11, the circuit surfaces can also be bonded together.

[0169] 1...laser processing device, 4, 5...driving unit (moving unit), 6...control unit, 7...spatial light modulator, 11...object, 11a...first surface, 11b...second surface, 12, 12a, 12b, 12c...modified area, 13, 13a, 13b, 13c...cracks, C, C1, C2, C3...focused spot, L, L1, L2, L3...laser light, 31...light source, 33...focusing lens. [Industrial Applicability]

[0170] A laser processing apparatus, a laser processing method, and a method for manufacturing a semiconductor component are provided that are capable of forming an oblique crack in an object. [Explanation of symbols]

[0171] 1...laser processing device, 4, 5...driving unit (moving unit), 6...control unit, 7...spatial light modulator, 11...object, 11a...first surface, 11b...second surface, 12, 12a, 12b, 12c...modified area, 13, 13a, 13b, 13c...cracks, C, C1, C2, C3...focused spot, L, L1, L2, L3...laser light, 31...light source, 33...focusing lens.

Claims

1. A light source that outputs laser light; a spatial light modulator for modulating the laser light output from the light source in accordance with a modulation pattern and outputting the modulated laser light; a focusing lens for focusing the laser light output from the spatial light modulator on an object to form a focused spot on the object; a moving unit for moving the focused spot relative to the object; a control unit that controls at least the spatial light modulator and the moving unit to perform a first formation process in which a first modified region and a first crack extending from the first modified region are formed in the object by setting a position of the focused spot in a Z direction intersecting an incident surface of the laser light in the object to a first Z position, while relatively moving the focused spot along a line extending in an X direction along the incident surface, and a second formation process in which a second modified region and a second crack extending from the second modified region are formed in the object by setting a position of the focused spot in the Z direction to a second Z position that is closer to the incident surface than the first Z position, while relatively moving the focused spot along the line. Equipped with In the first formation process, the control unit sets a position of the focused spot in a Y direction along the incident surface and intersecting the X direction to a first Y position; In the second formation process, the control unit sets the position of the focused spot in the Y direction to a second Y position shifted from the first Y position, and modulates the laser light by controlling the modulation pattern to be displayed on the spatial light modulator so that the beam shape of the focused spot in a YZ plane including the Y direction and the Z direction becomes an inclined shape that is inclined in the shift direction at least on the incident surface side from the center of the focused spot, thereby forming the second crack so as to be inclined in the shift direction in the YZ plane. Laser processing equipment.

2. In the first formation process, the control unit modulates the laser light so that a beam shape of the focused spot in the YZ plane has an inclined shape that is inclined in the shift direction at least on the incident surface side from the center of the focused spot, thereby forming the first crack so as to be inclined in the shift direction in the YZ plane.

2. The laser processing apparatus according to claim 1.

3. the modulation pattern includes a coma aberration pattern for imparting coma aberration to the laser light, In the second formation process, the control unit performs a first pattern control for forming the beam shape into the inclined shape by controlling a magnitude of the coma aberration caused by the coma aberration pattern.

3. The laser processing apparatus according to claim 1 or 2.

4. the modulation pattern includes a spherical aberration correction pattern for correcting spherical aberration of the laser beam, In the second formation process, the control unit performs a second pattern control for making the beam shape into the inclined shape by offsetting a center of the spherical aberration correction pattern in the Y direction with respect to a center of an entrance pupil plane of the condenser lens. The laser processing device according to any one of claims 1 to 3.

5. In the second formation process, the control unit performs a third pattern control for forming the beam shape into the inclined shape by causing the spatial light modulator to display the modulation pattern asymmetric with respect to an axis line along the X direction. The laser processing device according to any one of claims 1 to 4.

6. the modulation pattern includes an elliptical pattern for making the beam shape of the focused spot in an XY plane including the X direction and the Y direction into an elliptical shape having a longitudinal direction in the X direction, In the second formation process, the control unit performs a fourth pattern control to make the beam shape into the inclined shape by causing the spatial light modulator to display the modulation pattern so that the intensity of the elliptical pattern is asymmetric with respect to an axis line along the X direction. The laser processing device according to any one of claims 1 to 5.

7. The control unit performs a fifth pattern control in the second formation process to make the beam shape of the focused spot including the plurality of focused points the inclined shape by causing the spatial light modulator to display the modulation pattern for forming a plurality of focused points of the laser light arranged along the shift direction in the YZ plane. The laser processing device according to any one of claims 1 to 6.

8. The control unit performs the first formation process and then the second formation process on one of the lines set on the object along the X direction. The laser processing device according to any one of claims 1 to 7.

9. The control unit causes the spatial light modulator to display the modulation pattern including a branching pattern for branching the laser light, thereby simultaneously performing the first formation process and the second formation process for one of the lines set on the object. The laser processing device according to any one of claims 1 to 7.

10. a laser processing step of focusing a laser beam on an object to form a focused spot of the laser beam and moving the focused spot relative to the object, thereby performing laser processing on the object; The laser processing step includes: a first forming step of forming a first modified region and a first crack extending from the first modified region in the object by setting a position of the focused spot in a Z direction intersecting an incident surface of the laser light on the object at a first Z position and relatively moving the focused spot along a line extending in an X direction along the incident surface; a second forming step of forming a second modified region and a second crack extending from the second modified region by relatively moving the light focusing spot along the line while setting a position of the light focusing spot in the Z direction at a second Z position that is closer to the incident surface than the first Z position; Including, In the first forming step, a position of the focused spot in a Y direction that is along the incident surface and intersects with the X direction is set to a first Y position; In the second formation step, the position of the focused spot in the Y direction is set to a second Y position shifted from the first Y position, and the laser light is modulated so that the beam shape of the focused spot in a YZ plane including the Y direction and the Z direction becomes an inclined shape that is inclined in the shift direction at least on the incident surface side from the center of the focused spot, thereby forming the second crack so as to be inclined in the shift direction in the YZ plane. Laser processing method.

11. a laser processing step of focusing a laser beam on an object including a semiconductor to form a focused spot of the laser beam and moving the focused spot relative to the object, thereby performing laser processing on the object; a separation step of forming a semiconductor member from the object by separating a portion of the object after the laser processing step; Equipped with The laser processing step includes: a first forming step of forming a first modified region and a first crack extending from the first modified region in the object by setting a position of the focused spot in a Z direction intersecting an incident surface of the laser light on the object at a first Z position and relatively moving the focused spot along a line extending in an X direction along the incident surface; a second forming step of forming a second modified region and a second crack extending from the second modified region by relatively moving the light focusing spot along the line while setting a position of the light focusing spot in the Z direction at a second Z position that is closer to the incident surface than the first Z position; Including, In the first forming step, a position of the focused spot in a Y direction that is along the incident surface and intersects with the X direction is set to a first Y position; In the second formation step, a position of the focused spot in the Y direction is set to a second Y position shifted from the first Y position, and the laser light is modulated so that a beam shape of the focused spot in a YZ plane including the Y direction and the Z direction becomes an inclined shape inclined in the shift direction at least on the incident surface side from a center of the focused spot, thereby forming the second crack so as to be inclined in the shift direction in the YZ plane; In the separation step, the part of the object is separated at the boundaries of the first crack and the second crack, thereby forming the semiconductor member including a side surface that is an inclined surface defined by the second crack. A method for manufacturing a semiconductor component.

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