Laser processing system and laser processing method

Abstract

This laser processing system is for performing laser processing for forming a modified region on an object by irradiating the object with a laser beam, and the system includes: an input reception unit that receives input of the thickness of the object in a Z direction intersecting the surface of the object upon which the laser beam falls incident, and receives input of processing information including at least one of the processing time of the laser processing and the processing quality of the laser processing; a type determination unit that, on the basis of the processing information received by the input reception unit, determines the processing type of the laser processing according to the processing information; and a first condition determination unit that, on the basis of the thickness received by the input reception unit and the processing type determined by the type determination unit, determines a first processing condition, which is a processing condition constituting a criterion for the laser processing.

Description

Laser processing system and laser processing method

[0001] The present disclosure relates to a laser processing system and a laser processing method.

[0002] Patent Document 1 describes a method for setting processing conditions in laser processing. In this method, first, the user inputs, as essential processing target information, the thickness of a semiconductor wafer as the processing target and the incidence conditions of laser light on the semiconductor wafer. As the incidence conditions of laser light, either surface incidence or back surface incidence of laser light on the semiconductor wafer is specified. Subsequently, the processing conditions database is referred to, and the processing conditions for the semiconductor wafer are set based on the input processing target information.

[0003] Japanese Patent Application Laid-Open No. 2009-025995

[0004] One of the problems to be solved by the above method of Patent Document 1 in a laser processing apparatus is that it is difficult for the user side to appropriately set processing conditions such as the irradiation conditions of laser light so as to suit each individual processing target. Here, currently, for example, there are demands from users for tact-up of the processing time (processing time of the object) in laser processing and for the processing quality. Therefore, in the above technical field, it is desirable to be able to suitably set the processing conditions in accordance with such user demands.

[0005] An object of the present disclosure is to provide a laser processing system and a laser processing method capable of suitably setting processing conditions.

[0006] The laser processing system relating to this disclosure is a laser processing system for performing laser processing to form a modified region on an object by irradiating the object with laser light, comprising: an input receiving unit that receives input of processing information including the thickness of the object in the Z direction intersecting the incident surface of the laser light on the object, and the processing time and processing quality of the laser processing; a type determination unit that determines the type of laser processing according to the processing information based on the processing information received by the input receiving unit; a first condition determination unit that determines a first processing condition which is a standard processing condition for the laser processing based on the thickness received by the input receiving unit and the processing type determined by the type determination unit; and the Z The laser processing system comprises: a correction amount calculation unit that calculates the aberration correction amount of the laser light using an aberration correction curve that shows the relationship between the processing position of the laser processing in the direction and the aberration correction amount of the laser light; and a second condition determination unit that determines a second processing condition that includes the first processing condition determined by the first condition determination unit and the aberration correction amount calculated by the correction amount calculation unit, wherein the first processing condition includes a plurality of processing positions in the Z direction according to the thickness and a type of aberration correction curve associated with each of the plurality of processing positions, and the correction amount calculation unit calculates the aberration correction amount for each of the plurality of processing positions based on the first processing condition using the type of aberration correction curve corresponding to each of the processing positions.

[0007] The laser processing method relating to the present disclosure is a laser processing method for performing laser processing to form a modified region on an object by irradiating the object with laser light, comprising: an input receiving step for receiving input of processing information including the thickness of the object in the Z direction intersecting the incident surface of the laser light on the object, the processing time of the laser processing and the processing quality of the laser processing; a type determination step for determining the type of laser processing according to the processing information received in the input receiving step; and a first condition determination step for determining a first processing condition which is a standard processing condition for the laser processing, based on the thickness received in the input receiving step and the processing type determined in the type determination step. The laser processing method comprises: a correction amount calculation step of calculating the aberration correction amount of the laser light using an aberration correction curve that shows the relationship between the processing position of the laser processing in the Z direction and the aberration correction amount of the laser light; and a second condition determination step of determining a second processing condition that includes the first processing condition determined in the first condition determination step and the aberration correction amount calculated in the correction amount calculation step, wherein the first processing condition includes a plurality of processing positions in the Z direction according to the thickness and a type of aberration correction curve associated with each of the plurality of processing positions, and the correction amount calculation step calculates the aberration correction amount for each of the plurality of processing positions based on the first processing condition using the type of aberration correction curve corresponding to each of the processing positions.

[0008] In this system and method, first, the system receives input of processing information including the thickness of the object, the processing time for laser processing (e.g., the processing time required to process the object), and the processing quality of the laser processing. Next, based on the received processing information, the type of laser processing corresponding to that processing information is determined. Subsequently, based on the received thickness of the object and the determined processing type, a first processing condition, which is the standard processing condition for laser processing, is determined. Then, a second processing condition, which includes this first processing condition, is determined. In other words, according to this system and method, a processing type that conforms to the user's requests (input) regarding processing time and processing quality is determined, and a second processing condition based on that processing type is determined. Therefore, the processing conditions can be set appropriately.

[0009] Incidentally, when determining the type of laser processing according to processing time and processing quality, it is desirable to control the amount of crack extension from the modified region. For example, in processing types that prioritize faster processing time, the amount of crack extension from the modified region should be increased, while in processing types that prioritize improved processing quality, the amount of crack extension from the modified region should be decreased. One way to control the amount of crack extension from the modified region is to adjust the amount of aberration correction of the laser beam at each processing position inside the object. In this system and method, the first processing condition, which is determined according to the processing type, includes multiple processing positions in the Z direction according to the thickness, and the type of aberration correction curve associated with each of the multiple processing positions. The aberration correction amount is calculated using these types of aberration correction curves. The second processing condition is then determined including the calculated aberration correction amount. Thus, processing conditions that can control the amount of crack extension are suitably set according to the processing type that meets the requirements for processing time and processing quality.

[0010] The laser processing system according to this disclosure may also be [2] "the laser processing system according to [1] above, wherein the laser processing includes irradiating the object with laser light to form the modified region, and cutting the object using the modified region, and the processing quality includes at least one of the bending strength of the cut piece obtained by cutting the object, damage to the surface of the object on the side opposite to the incident surface by the laser light, the amount of meandering of the modified region when viewed from the Z direction, and the straightness of the cut surface of the cut piece." In this case, more optimal processing conditions can be set according to the various processing quality described above.

[0011] The laser processing system relating to this disclosure may also be [3] "the laser processing system according to [1] or [2] above, which includes a display unit that displays at least a part of at least one of the first processing conditions determined by the first condition determination unit and the second processing conditions determined by the second condition determination unit." In this case, the user can easily confirm the processing conditions.

[0012] The laser processing system relating to this disclosure may also be [4] "the laser processing system according to [3] above, wherein when the display unit displays the second processing conditions, at least the aberration correction amount among the second processing conditions is not displayed." The appropriate aberration correction amount according to the processing type may include machine differences in the part of the laser processing system that irradiates the object with laser light (the laser processing unit described later). Therefore, by not displaying the aberration correction amount when displaying the second processing conditions, it becomes possible for the user to confirm certain processing conditions regardless of the presence or absence of machine differences.

[0013] The laser processing system relating to this disclosure may also be [5] "the laser processing system according to [3] or [4] above, wherein the display unit displays the processing position as the position inside the object." In this case, the user can confirm the actual processing position inside the object.

[0014] The laser processing system according to this disclosure may also be [6] "a laser processing system according to any one of [1] to [5] above, comprising: a laser processing unit that performs laser processing of the object based on the second processing conditions determined by the second condition determination unit; and an adjustment unit that adjusts the second processing conditions based on the results of the laser processing of the object by the laser processing unit." In this case, more optimal processing conditions can be set by adjusting the second processing conditions.

[0015] The laser processing system according to this disclosure may also be [7] "the laser processing system according to any of [1] to [6] above, wherein the processing type includes a first processing type, a second processing type, and a third processing type, the first processing type is a processing type in which the number of layers of the modified region stacked in the Z direction over a certain thickness range of the object is greater than the number of layers of the second processing type and the third processing type, the second processing type is a processing type in which the number of layers is less than the number of layers of the first processing type and greater than the third processing type, and the third processing type is a processing type in which the number of layers is less than the number of layers of the first processing type and the second processing type." In this case, it becomes possible to reliably determine the processing type in accordance with the user's requirements for processing time and processing quality.

[0016] The laser processing system according to this disclosure may also be [8] "the laser processing system according to [7] above, wherein the type determination unit determines the first processing type as the processing type when the processing information received by the input receiving unit includes the processing time and the processing time is a first hour; the type determination unit determines the second processing type as the processing type when the processing information received by the input receiving unit includes the processing time and the processing time is a second hour which is shorter than the first hour; and the type determination unit determines the third processing type as the processing type when the processing information received by the input receiving unit includes the processing time and the processing time is a third hour which is shorter than both the first and second hours." In this case, it becomes possible to determine a processing type that is in line with the user's request for processing time.

[0017] The laser processing system according to this disclosure may also be [9] "a laser processing system according to any one of [1] to [8] above, comprising a first database that holds at least a plurality of processing types, wherein the type determination unit determines the processing type by referring to the first database and selecting the processing type from the plurality of processing types held in the first database according to the processing information received by the input receiving unit." In this case, the processing type can be easily determined by referring to the database.

[0018] The laser processing system according to this disclosure may also be

[10] "the laser processing system according to [9] above, wherein the first database holds a plurality of first processing conditions associated with each of a plurality of processing types, and the first condition determination unit determines the first processing conditions by referring to the first database and selecting the first processing conditions corresponding to the thickness received by the input receiving unit from among the plurality of first processing conditions associated with the processing type determined by the type determination unit." In this case, the first processing conditions can be easily determined by referring to the database.

[0019] The laser processing system according to this disclosure may also be

[11] "a laser processing system according to any of [1] to

[10] above, comprising a second database that holds a plurality of types of aberration correction curves, wherein the correction amount calculation unit selects the aberration correction curve included in the first processing conditions by referring to the second database, and calculates the aberration correction amount using the selected aberration correction curve." In this case, the aberration correction curve can be easily determined (selected) and the aberration correction amount can be calculated by referring to the database. The first database and the second database may be the same or they may be different from each other.

[0020] This disclosure provides a laser processing system and a laser processing method that allow for the optimal setting of processing conditions.

[0021] Figure 1 is a schematic diagram showing the configuration of a laser processing apparatus according to one embodiment. Figure 2 is a schematic diagram showing the configuration of the irradiation unit shown in Figure 1. Figure 3 is a schematic diagram showing the configuration of the control unit shown in Figure 1. Figure 4 is a diagram showing one step of the laser processing method according to this embodiment. Figure 5 is a diagram showing one step of the laser processing method according to this embodiment. Figure 6 is a diagram for explaining an example of processing quality. Figure 7 is a diagram showing one step of the laser processing method according to this embodiment. Figure 8 is a diagram showing the modified region and crack formation state when processing is performed according to each processing type. Figure 9 is a diagram showing a specific example of the first processing type shown in Figure 8. Figure 10 is a diagram showing a specific example of the second processing type shown in Figure 8. Figure 11 is a diagram showing a specific example of the third processing type shown in Figure 8. Figure 12 is a diagram showing one step of the laser processing method according to this embodiment. Figure 13 is a graph showing an example of an aberration correction curve. Figure 14 is a graph showing an example of an aberration correction curve that takes machine differences into account. Figure 15 is a graph showing the conversion formula between the processing position inside the object and the Z-shift amount. Figure 16 is a diagram showing one step of the laser processing method according to this embodiment. Figure 17 is a diagram showing one step of the laser processing method according to this embodiment. Figure 18 is a diagram showing one step of the laser processing method according to this embodiment. Figure 19 is a diagram showing one step of the laser processing method according to this embodiment.

[0022] An embodiment will be described below with reference to the drawings. In each drawing, the same or corresponding parts will be denoted by the same reference numerals, and redundant explanations may be omitted. In addition, each drawing may show a Cartesian coordinate system defined by the X, Y, and Z axes.

[0023] Figure 1 is a schematic diagram showing the configuration of a laser processing apparatus according to one embodiment. As shown in Figure 1, the laser processing apparatus 1 comprises a stage (support unit) 2, an irradiation unit 3, moving units 4 and 5, and a control unit 6. The laser processing apparatus 1 is a device for performing laser processing to form a modified region 12 on an object 11 by irradiating the object 11 with laser light L. For example, the laser processing apparatus 1 may be part of a laser processing system 100. In this case, the laser processing system 100 may include a plurality of laser processing apparatuses 1 as laser processing units for performing laser processing, and may also include a system control unit configured by a computer connected to the plurality of laser processing apparatuses 1. The parts of the laser processing apparatus 1 will be described next.

[0024] Stage 2 supports the object 11, for example, by holding a film attached to the object 11. Stage 2 may be rotatable about an axis parallel to the Z direction. Stage 2 may be movable along the X and Y directions, respectively. The X and Y directions are the first and second horizontal directions, which intersect (are orthogonal to each other), and the Z direction is the vertical direction.

[0025] The irradiation unit 3 is for irradiating the object 11 supported on the stage 2 with laser light L. The irradiation unit 3 focuses the laser light L, which is penetrating to the object 11, and irradiates the object 11 with it. When the laser light L is focused inside the object 11 supported on the stage 2, the laser light L is particularly absorbed in the portion corresponding to the focal point C of the laser light L, and a modified region 12 is formed inside the object 11.

[0026] The modified region 12 is a region whose density, refractive index, mechanical strength, and other physical properties differ from those of the surrounding unmodified region. Examples of modified regions 12 include melting regions, crack regions, dielectric breakdown regions, and refractive index change regions. The modified region 12 may be formed such that cracks extend from the modified region 12 toward the incident side of the laser beam L and the opposite side. Such modified regions 12 and cracks can be used, for example, to cut the object 11. Alternatively, the modified region 12 may be formed such that cracks extend from the modified region 12 into the plane of the object 11 along the incident surface of the laser beam L. Such modified regions 12 and cracks can be used to delaminate the object 11.

[0027] As an example, when stage 2 is moved along the X direction and the focal point C is moved relative to the object 11 along the X direction, multiple modified spots 12s are formed in a line along the X direction. Each modified spot 12s is formed by irradiation with one pulse of laser light L. A row of modified regions 12 is a collection of multiple modified spots 12s arranged in a line. Adjacent modified spots 12s may be connected to each other or separated from each other, depending on the relative movement speed of the focal point C with respect to the object 11 and the repetition frequency of the laser light L.

[0028] The moving unit 4 includes a first moving unit 41 that moves the stage 2 in one direction within a plane intersecting (orthogonal to) the Z direction, and a second moving unit 42 that moves the stage 2 in another direction within the plane intersecting (orthogonal to) the Z direction. For 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. Alternatively, the moving unit 4 may rotate the stage 2 around an axis parallel to the Z direction as the axis of rotation. The moving unit 5 supports the irradiation unit 3. The moving unit 5 moves the irradiation unit 3 along the X, Y, and Z directions. When the stage 2 and / or the irradiation unit 3 are moved while the focal point C of the laser beam L is formed, the focal point C is moved relative to the object 11. That is, the moving units 4 and 5 move at least one of the stage 2 and the irradiation unit 3 in order to move the focal point C of the laser beam L relative to the object 11.

[0029] The control unit 6 controls the operation of the stage 2, the irradiation unit 3, and the moving units 4 and 5. The control unit 6 has a processing unit, a storage unit, and an interface unit (not shown). The processing unit is configured as a computer device including a processor, memory, storage, and communication devices. In the processing unit, the processor executes software (programs) loaded into memory, etc., and controls the reading and writing of data in memory and storage, as well as communication by the communication devices, thereby realizing each function of the control unit 6. The storage unit is, for example, a hard disk, and stores various types of data.

[0030] Figure 2 is a schematic diagram showing the configuration of the irradiation unit shown in Figure 1. Figure 2 shows a hypothetical line A indicating the planned laser processing. As shown in Figure 2, the irradiation unit 3 includes a light source 31, a spatial light modulator 7, and a focusing lens (focusing unit) 33. The light source 31 outputs laser light L, for example, by a pulse oscillation method. The irradiation unit 3 may also be configured to not have a light source 31, and to introduce laser light L from outside the irradiation unit 3. The spatial light modulator 7 modulates the laser light L output from the light source 31. The focusing lens 33 focuses the laser light L modulated by the spatial light modulator 7 and output from the spatial light modulator 7 (i.e., the laser light that has passed through the spatial light modulator 7) toward the object 11.

[0031] In the spatial light modulator 7, when a signal indicating a modulation pattern is input from the control unit 6, the modulation pattern is displayed according to the signal. The modulation pattern is for modulating the laser light L. In the spatial light modulator 7, when the modulation pattern is displayed and laser light L is incident from the outside, reflected, and emitted to the outside, the laser light L is modulated according to the displayed modulation pattern. In this way, the spatial light modulator 7 makes it possible to modulate the laser light L (for example, modulating the intensity, amplitude, phase, polarization, etc. of the laser light L) by appropriately setting the displayed modulation pattern.

[0032] As described above, the laser light L output from the light source 31 is incident on the focusing lens 33 via the spatial light modulator 7, and is focused into the object 11 by the focusing lens 33, thereby forming a modified region 12 and cracks extending from the modified region 12 in the object 11 at the focusing point C. Furthermore, by controlling the movement units 4 and 5 of the control unit 6, the focusing point C is moved relative to the object 11, thereby forming the modified region 12 and cracks along the direction of movement of the focusing point C.

[0033] Figure 3 is a schematic diagram showing the configuration of the control unit shown in Figure 1. As shown in Figure 3, the control unit 6 comprises an input reception unit 61 (input reception unit, display unit), a type determination unit 62, a first condition determination unit 63, a correction amount calculation unit 64, a second condition determination unit 65, an adjustment unit 66, and a database 67 (first database, second database). The input reception unit 61 is an interface unit that displays various information and accepts input of various information from the user. The input reception unit 61 constitutes a GUI (Graphical User Interface).

[0034] Next, the laser processing method according to this embodiment will be described while explaining the operation of each part of the control unit 6 shown in Figure 3. Here, first, as shown in Figure 4, the input receiving unit 61 receives input from the user of processing information including the thickness of the object 11 in the Z direction intersecting the incident surface of the laser light L on the object 11 (for example, the first surface 11a), and at least one of the processing time and processing quality of the laser processing (step S101, input receiving step).

[0035] Specifically, in the example shown in Figure 4(a), the input reception unit 61 displays input reception information 200 that prompts the user to input the wafer thickness 201, which indicates the thickness of the object 11, and the processing time 202, which indicates the processing time for laser processing of the object 11. The user can input the desired thickness of the object 11 (for example, by using a pull-down menu) by manipulating the wafer thickness 201 area of ​​the input reception information 200 on the input reception unit 61. In the illustrated example, "300 μm" is input (selected, for example, by using a pull-down menu) as the thickness of the object 11.

[0036] Furthermore, the ability of a user to input or select certain information means that the input receiving unit 61 can accept the input of that information (the same applies hereafter).

[0037] Furthermore, the user can input the desired laser processing time (for example, by using a pull-down menu) by manipulating the processing time 202 area of ​​the input reception information 200 on the input reception unit 61. The laser processing time (or processing time) refers to the time it takes for the laser processing of the object 11 to be completed, and corresponds to the laser processing speed. For this reason, in the illustrated example, "medium speed" is input (selected for example by using a pull-down menu) as the laser processing time. As the laser processing time, the user can select "high speed" to complete the laser processing in a shorter time, "low speed" which takes longer to complete the laser processing, and "any" which does not specify the time it takes to complete the laser processing.

[0038] Furthermore, as shown in Figure 4(b), the input reception information 200 may also include another processing time 203, which is another measure of the processing time for laser processing. The user can input the processing time (processing time / piece) as the processing time by manipulating the processing time 203 area of ​​the input reception information 200 on the input reception unit 61, for example by selecting from a pull-down menu. In the illustrated example, "10 minutes / piece" is entered.

[0039] Furthermore, as shown in Figure 5, in step S101, the input reception unit 61 may receive input regarding the processing quality of the laser processing from the user. Specifically, the input reception unit 61 may display input reception information 200A that prompts the user to input a quality level 204 indicating the processing quality of the laser processing, and an incident surface 205 indicating the incident manner of the laser light on the object 11. The user can input the desired processing quality by manipulating the quality level 204 area of ​​the input reception information 200A on the input reception unit 61.

[0040] As shown in Figures 5 and 6, the processing quality includes, if the laser processing includes processing to cut the object 11 using a modified region 12, the flexural strength of the cut piece 11p obtained by cutting the object 11, the damage caused by the laser beam L to the surface of the object 11 opposite to the incident surface (e.g., the first surface 11a) (the incident back surface, e.g., the second surface 11b), the amount of meandering of the modified region 12 when viewed from the Z direction, and the straightness of the cut surface 11s of the cut piece 11p.

[0041] As shown in Figure 5, the user can select "High Flexural Strength" quality level 204 if they require high flexural strength in the cut piece 11p as a processing quality, or "Damage Suppression" quality level 204 if they require damage suppression by the laser light L on the incident back surface. Furthermore, the user can select "Modified Layer Meandering within AA μm" quality level 204 if they require the amount of meandering in the modified region 12 to be kept within a certain amount as a processing quality, or "End Face Straightness within BB μm" quality level 204 if they require the amount of irregularities indicating the straightness of the cut surface 11s to be kept within a certain amount. In addition, the user may input specific numerical values ​​for "AA μm" and "BB μm" as described above.

[0042] Furthermore, the user can input the desired method of laser beam L incidence by manipulating the area of ​​the incident surface 205 of the input reception information 200A on the input reception unit 61. For example, if the user requests that the second surface 11b of the object 11, on which the device layer is formed, be the incident surface for the laser beam L, they can select "surface incidence" for the incident surface 205. Alternatively, if the user requests that the first surface 11a of the object 11 be the incident surface for the laser beam L, they can select "back surface incidence" for the incident surface 205. In addition, if the user requests that the laser beam L be incident on the object 11 via a tape that has some function such as protection or external force application, they can also select "incidence through tape" for the incident surface 205.

[0043] In the subsequent process, as shown in FIG. 7, the type determination unit 62 of the control unit 6 determines the processing type 210 of laser processing corresponding to the processing information (processing time and / or processing quality) received by the input reception unit 61 in step S101 (step S102, type determination step). The processing type 210 is the processing concept of laser processing of the object 11 and includes a first processing type 211, a second processing type 212, and a third processing type 213.

[0044] FIG. 8 is a diagram showing the modification region and the formation state of cracks when processing is performed along each processing type. As shown in FIGS. 7 and 8, the first processing type 211 is a processing concept of "stacking modification layers", and is a processing type in which a large number of modification layers 120 are stacked at a high density along the Z direction. The modification layer 120 is a layer including a group of modification regions 12 formed along line A when the object 11 is irradiated with the laser beam L while relatively moving the condensing point C of the laser beam L along line A.

[0045] FIG. 9 is a diagram showing a specific example of the first processing type shown in FIG. 8. In the example shown in FIG. 9, in the first processing type 211, the first surface 11a of the object 11 is used as the incident surface of the laser beam L, and as the modification layer 120, modification layers 121 to 127 are formed on the object 11 in order from the second surface 11b side. Here, except for a part on the first surface 11a side of the object 11, the modification layer 120 is formed substantially over the entire Z direction of the object 11.

[0046] As shown in FIGS. 7 and 8, the second processing type 212 is a processing concept of "crack stacking + quality", and is a processing type in which the modification layer 120 is stacked at a medium density along the Z direction, and the spaces between the modification layers 120 are connected by cracks 13 extending from each of the modification layers 120.

[0047] FIG. 10 is a diagram showing a specific example of the second processing type shown in FIG. 8. In the example shown in FIG. 10, in the second processing type 212, the first surface 11a of the object 11 is the incident surface of the laser beam L, and as the modified layer 120, a modified layer 121, a modified layer 122 on the second surface 11b side of the modified layer 121, and a modified layer 123 on the first surface 11a side of the modified layer 121 are formed on the object 11 in this order. Further, cracks 13 are formed between the modified layer 122 and the second surface 11b, between the modified layer 122 and the modified layer 121, between the modified layer 121 and the modified layer 123, and between the modified layer 123 and the first surface 11a.

[0048] As shown in FIGS. 7 and 8, the third processing type 213 is a processing concept of "crack stacking + tact", and is a processing type in which the modified layer 120 is laminated at a low density along the Z direction and the spaces between the modified layers 120 are connected by the cracks 13 extending from each of the modified layers 120.

[0049] FIG. 11 is a diagram showing a specific example of the third processing type shown in FIG. 8. In the example shown in FIG. 11, in the third processing type 213, the first surface 11a of the object 11 is the incident surface of the laser beam L, and as the modified layer 120, a modified layer 121 and a modified layer 122 are formed on the object 11 in this order from the second surface 11b side. Further, cracks 13 are formed between the modified layer 121 and the second surface 11b, between the modified layer 121 and the modified layer 122, and between the modified layer 122 and the first surface 11a.

[0050] Thus, the first processing type 211 is a processing type in which the number of laminated modified regions 12 (modified layer 120) laminated in the Z direction in a certain thickness range of the object 11 is larger than the number of laminations of the second processing type 212 and the third processing type 213. The second processing type 212 is a processing type in which the number of laminations is smaller than the number of laminations of the first processing type 211 and larger than the third processing type 213. The third processing type 213 is a processing type in which the number of laminations is smaller than the number of laminations of the first processing type 211 and the second processing type 212.

[0051] The number of layers of the modified layer 120 stacked over a certain thickness range of the object 11 is related to processing time and processing quality. Specifically, as the number of layers increases, processing time tends to increase (becomes slower) and processing quality tends to improve, while as the number of layers decreases, processing time tends to decrease (becomes faster) and processing quality tends to decline.

[0052] For example, in the first processing type 211, the processing quality is evaluated based on the straightness of the cut surface 11s when viewed from a direction intersecting the Z direction (e.g., the Y direction) (end face straightness), the straightness of the cut surface 11s when viewed from the incident surface (e.g., the first surface 11a) side (incident surface straightness), and the straightness of the cut surface 11s when viewed from the incident back surface (e.g., the second surface 11b) side (incident back surface straightness), all of which receive an A rating. However, the processing time is evaluated based on the fact that, for example, about 20 layers are required for an object 11 with a thickness of 775 μm, resulting in a low processing speed. In the first processing type 211, damage to the incident back surface by the laser beam L (incident back surface damage) receives an A rating. Furthermore, processing quality is evaluated in four stages, from the best A rating to B, C, and D ratings. It should be noted that the evaluation of processing quality is merely an example, and there may be cases where the evaluation (ratings A to D) is not as described above (the same applies below).

[0053] Furthermore, in the second processing type 212, the processing quality is evaluated as follows: straightness of the end face and straightness of the incident face are evaluated as B, and straightness of the incident back surface and damage to the incident back surface are evaluated as A. In terms of processing time, for example, for an object 11 with a thickness of 775 μm, about 10 layers are sufficient, and the processing speed is medium.

[0054] Furthermore, in the third processing type 213, the processing quality is evaluated as follows: end face straightness, incident back surface straightness, and incident back surface damage all receive a rating of C. For processing time, for example, for an object 11 with a thickness of 775 μm, about 5 layers are sufficient, resulting in high processing speed. In addition, in the third processing type 213, incident surface straightness receives a rating of D.

[0055] In this way, the processing type 210 can be determined based on the processing time and processing quality requested by the user. For example, in process S102, if the processing information received by the input receiving unit 61 in process S101 includes processing time and the processing time is a first time (for example, low speed), the processing type determination unit 62 can determine the first processing type 211 as the processing type 210. If the processing time is a second time (medium speed) which is shorter than the first time, the processing type 210 can determine the second processing type 212 as the processing type 210. If the processing time is a third time (high speed) which is shorter than both the first and second times, the processing type 313 as the processing type 210.

[0056] The processing type 210 is stored in the database 67. Therefore, in process S102, the type determination unit 62 can determine the processing type 210 by referring to the database 67 and selecting a processing type 210 from among the multiple processing types 210 stored in the database 67 that corresponds to the processing information received by the input reception unit 61 in process S101. In addition, if the processing time is "not specified" in the processing information received by the input reception unit 61 in process S101 (i.e., the processing information does not substantially include processing time), the type determination unit 62 can determine a processing type 210 that matches the processing quality from among the processing information received by the input reception unit 61 in process S101.

[0057] In the subsequent step, as shown in Figure 12, the first condition determination unit 63 determines the first processing conditions 220, which are the processing conditions that serve as the basis for laser processing, based on the thickness of the object 11 received by the input reception unit 61 in step S101 and the processing type 210 determined by the type determination unit 62 in step S102 (step S103, first condition determination step). Figure 12 shows an example of the first processing conditions 220 determined when the thickness of the object 11 is input as 300 μm in step S101 and the second processing type 212 is determined as the processing type 210 in step S102.

[0058] The first processing conditions 220 include the processing position 221, pulse pitch (P.P. in the figure) 222, processing speed 223, output 224, frequency 225, and aberration correction curve 226, each of which is set for the modified layer 121, modified layer 122, and modified layer 123, respectively. The processing position 221 indicates the processing position in the Z direction within the object 11 (the position where the focusing point C is aligned to form the modified region 12) (μm), and is included in multiple (in this case, three) first processing conditions 220 in the Z direction depending on the thickness of the object 11.

[0059] The pulse pitch 222 indicates the pulse pitch (μm) of the laser beam L, the processing speed 223 indicates the relative movement speed (mm / sec) of the focal point C along line A, the output 224 indicates the output (W) of the laser beam L, the frequency 225 indicates the pulse repetition frequency (kHz) of the laser beam L, and the aberration correction curve 226 indicates the type of aberration correction curve used when calculating the aberration correction amount, and is included in the first processing condition 220, corresponding to each of the multiple processing positions 221.

[0060] The first processing conditions 220 are linked to the processing type 210 and stored in the database 67. More specifically, in the database 67, multiple first processing conditions 220 are linked to each of the multiple processing types 210, for example, for each thickness of the object 11. Therefore, in process S103, the first condition determination unit 63 can determine the first processing conditions 220 by referring to the database 67 and selecting the first processing conditions 220 corresponding to the thickness of the object 11 received by the input reception unit 61 in process S101 from among the multiple first processing conditions 220 linked to the processing type 210 determined by the type determination unit 62 in process S102.

[0061] Here, as shown in Figure 9, in the first processing type 211, the modified layers 121 and 122 located on the incident back surface (second surface 11b) side of the object 11 can be formed such that the crack 13 propagates to a certain extent from the modified layers 121 and 122 so that the crack 13 reaches the second surface 11b. Also in the first processing type 211, the modified layers 126 and 127 located on the incident surface (first surface 11a) side of the object 11 can be formed such that the crack 13 propagates to a certain extent from the modified layers 126 and 127 so that the crack 13 reaches the first surface 11a. On the other hand, in the first processing type 211, the modified layers 123 to 125 located in the middle part of the object 11 can be formed such that the crack 13 does not propagate too much from each of the modified layers 123 to 125.

[0062] Furthermore, as shown in Figure 10, in the second processing type 212, the first modified layer 121 formed between the modified layer 122 located on the incident back surface (second surface 11b) side of the object 11 and the modified layer 123 located on the incident surface (first surface 11a) side is formed so that cracks do not propagate much from the modified layer 121, thereby functioning to guide the propagation of cracks 13 extending from the modified layers 122 and 123. On the other hand, in the second processing type 212, the modified layers 122 and 123 may be formed so that cracks propagate significantly from the modified layers 122 and 123.

[0063] Furthermore, as shown in Figure 11, in the third processing type 213, the modified layers 121 and 122 can be formed such that cracks propagate significantly from the modified layers 121 and 122, respectively.

[0064] Thus, the degree to which the modified layer 120 (modified region 12) propagates cracks 13 differs depending on the processing location in each processing type 210. The degree to which cracks 13 propagate from the modified layer 120 is thought to be related to the amount of aberration correction of the laser beam L when forming the modified layer 120 (modified region 12). Therefore, it is desirable to appropriately calculate the aberration correction amount using aberration correction curves corresponding to each processing type 210 and each processing location.

[0065] Figure 13 is a graph showing an example of an aberration correction curve. In each graph shown in Figure 13, the horizontal axis represents the amount of movement of the focusing lens 33 in the Z direction (hereinafter referred to as "Z movement"), and the vertical axis represents the aberration correction amount (aberration correction value in the notation shown). That is, the aberration correction curves C1 and C2 shown in Figure 13 (straight lines in the example shown) show the relationship between the Z movement and the aberration correction amount at that Z movement. Figure 13(a) shows the relationship between the Z movement and the aberration correction amount during ideal focusing (the state in which the laser light L is most focused at the focusing point C), and Figure 13(b) shows the relationship between the Z movement and the aberration correction amount during inevitable aberration (spherical aberration that inevitably occurs within the object 11).

[0066] According to the aberration correction curve C1 for ideal focusing shown in Figure 13(a), the optimal aberration correction amount (optimal correction) is obtained for theoretically focusing the laser beam L the most with respect to the Z-shift amount. Therefore, by calculating the aberration correction amount using the aberration correction curve C1 and irradiating with the laser beam L at that aberration correction amount, the propagation of cracks 13 from the modified layer 120 (modified region 12) formed at that time can be greatly increased. For this reason, it is considered desirable to use an aberration correction curve close to the aberration correction curve C1 at processing locations where it is required to greatly propagate the cracks 13.

[0067] Furthermore, according to the aberration correction curve C2 in Figure 13(b) for inevitable aberration, a constant small aberration correction amount (0 in the illustrated example) can be obtained regardless of the Z-shift amount. Therefore, if the aberration correction amount is calculated using the aberration correction curve C2 and the laser beam L is irradiated with this aberration correction amount, the aberration correction of the laser beam L is suppressed, resulting in a state where the focusing ability at the focal point C of the laser beam L is shifted (full blur). Therefore, the propagation of cracks 13 from the modified layer 120 (modified region 12) formed at that time can be reduced. For this reason, it is considered desirable to use an aberration correction curve close to the aberration correction curve C2 at processing locations where it is required to minimize the propagation of cracks 13.

[0068] Furthermore, if the required degree of crack propagation 13 is moderate, an aberration correction curve (half-blur) between aberration correction curve C1 and aberration correction curve C2 (for example, the average) can be used.

[0069] Here, the relationship between the Z-axis movement and the aberration correction amount may include variations in the laser processing apparatus 1. Therefore, when calculating the aberration correction amount, it is desirable to use an aberration correction curve that takes these variations into account. Figure 14 is a graph showing an example of an aberration correction curve that takes these variations into account.

[0070] Figure 14(a) shows an example of an optimal aberration correction curve C11 obtained by taking into account the differences between the optimally corrected aberration correction curve C1 and the camera. Figure 14(b) shows an example of a fully blurred aberration correction curve C21 obtained by taking into account the differences between the fully blurred aberration correction curve C2 and the camera. For example, aberration correction curves C11 and C21 may be set with the aim of falling within the ranges R1 and R2 of ±30 and ±25 (of the aberration correction amount) relative to aberration correction curves C1 and C2, respectively. Figure 14(c) shows an example of a half-blurred aberration correction curve C31 obtained by taking into account the differences between the half-blurred aberration correction curve between aberration correction curve C1 and aberration correction curve C2. For example, aberration correction curve C31 may be set with the aim of falling within the range R3 between aberration correction curve C1 and aberration correction curve C2.

[0071] In the laser processing apparatus 1, the database 67 stores the aberration correction curve C11 for optimal correction, the aberration correction curve C21 for full blurring, and the aberration correction curve C31 for half blurring, which are set as described above. Furthermore, the aberration correction curve 226 for the first processing condition 220 includes the type of aberration correction curve ("A Optimal Correction", "B Full Blurring", and "C Half Blurring") which of the above aberration correction curves should be used at each processing position 221 (see Figure 12).

[0072] Therefore, in the subsequent step, the correction amount calculation unit 64 calculates the aberration correction amount of the laser beam L using aberration correction curves C11, C21, and C31 that show the relationship between the processing position of the laser processing in the Z direction and the aberration correction amount of the laser beam L (step S104, correction amount calculation step) (see Figures 16 and 17). Specifically, in step S104, the correction amount calculation unit 64 calculates the aberration correction amount for each of the multiple processing positions 221 based on the first processing conditions 220, using an aberration correction curve of the type corresponding to each of the processing positions 221. In addition, in step S104, the correction amount calculation unit 64 can select an aberration correction curve included in the first processing conditions 220 by referring to the database 67, and calculate the aberration correction amount using the selected aberration correction curve.

[0073] Here, as partially shown in Figure 16(a), in the first machining condition 220, the machining position 221 is included as the position inside the object 11 ("machining position Siμm"). Therefore, in order to calculate the aberration correction amount for each of the machining positions 221 using the aberration correction curves C11, C21, C31, etc., it is necessary to convert the position inside the object 11 into a Z-shift amount.

[0074] Figure 15 is a graph showing the conversion formula between the processing position inside the object and the Z-axis movement. In Figure 15, the horizontal axis represents the Z-axis movement (notation ZH (μm) in the figure), and the vertical axis represents the processing position inside the object 11 (notation processing position Si (μm) in the figure). Graph G1 in Figure 15 shows the conversion formula for the optimal correction aberration correction curve C11, graph G2 shows the conversion formula for the full blur aberration correction curve C21, and graph G3 shows the conversion formula for the half blur aberration correction curve C31.

[0075] As shown in Figure 15, the conversion formula differs depending on the aberration correction curve. Therefore, in step S104, the correction amount calculation unit 64 converts each value of the processing position 221 into a Z-movement amount using a conversion formula corresponding to the type of aberration correction curve. For example, as shown in Figure 16(a), the first processing condition 220 indicates that the A-optimal correction aberration correction curve C11 is used at the processing positions 221 of the modified layers 122 and 123. Therefore, in step S104, as shown in Figures 15 and 16(b), the correction amount calculation unit 64 first uses the conversion formula (graph G1) of the aberration correction curve C11 to convert the processing positions 221 of all modified layers 121 to 123, which are 150 μm, 250 μm, and 50 μm, into Z-movement amounts of 40 μm, 65 μm, and 15 μm, respectively, and obtains the converted movement amount 231.

[0076] Furthermore, as shown in Figure 16(a), the first processing condition 220 indicates that the aberration correction curve C21 for full B blurring is used at the processing position 221 of the modified layer 121. Accordingly, in subsequent step S104, the correction amount calculation unit 64 uses the conversion formula (graph G2) for the aberration correction curve C21 to convert the processing positions 221 of all modified layers 121 to 123, which are 150 μm, 250 μm, and 50 μm, into Z-movement amounts of 45 μm, 70 μm, and 15 μm, respectively, as shown in Figures 15 and 16(c), and obtains another converted movement amount 232.

[0077] Then, in step S104, the correction amount calculation unit 64 selects 65 μm and 15 μm, which are the Z-movement amounts at the processing position 221 of the modified layers 122 and 123 that are suitable for the A-optimal correction, from the converted movement amount 231, and calculates the aberration correction amounts (50 and 15) corresponding to each Z-movement amount, as shown in Figure 17(a), using the aberration correction curve C11 of the A-optimal correction. As a result, the correction amount calculation unit 64 obtains the A-aberration correction value 241, which is the aberration correction amount for the A-optimal correction at the processing position 221 of the modified layers 122 and 123.

[0078] Furthermore, in step S104, the correction amount calculation unit 64 selects 45 μm, which is the Z-movement amount at the processing position 221 of the modified layer 121 that is suitable for B-full blurring, from the converted movement amount 232 (see Figure 16(c)), and uses the aberration correction curve C21 for B-full blurring to calculate the aberration correction amount (10) corresponding to the Z-movement amount as shown in Figure 17(b). As a result, the correction amount calculation unit 64 obtains the B-aberration correction value 242, which is the aberration correction amount for B-full blurring at the processing position 221 of the modified layer 121.

[0079] Then, as shown in Figure 18, the correction amount calculation unit 64 combines the A-aberration correction value 241 and the B-aberration correction value 242 to generate an aberration correction amount 252 (aberration correction value in the figure) for all processing positions 221, and acquires aberration correction data 250 including the aberration correction amount 252, processing positions 221, Z-shift amount (lens position (Zμm) in the figure) 251, and aberration correction curve 226.

[0080] Then, in the next step, as shown in Figure 19, the second condition determination unit 65 determines the second processing conditions 260, which include the first processing conditions 220 determined by the first condition determination unit 63 and the aberration correction amount 252 calculated by the correction amount calculation unit 64 (step S105, second condition determination step).

[0081] Subsequently, in the laser processing apparatus 1, the input receiving unit 61 can display the second processing conditions 260 determined in step S105. At this time, the input receiving unit 61 can hide the aberration correction amount 252 of the second processing conditions 260 (i.e., only the first processing conditions 220 are displayed in the illustrated example). In other words, the input receiving unit 61 may display a part of the second processing conditions 260 while hiding the rest. Also, here, the input receiving unit 61 displays the processing position 221 as the internal position of the object 11.

[0082] Based on the above, the processing conditions for laser processing (second processing conditions 260) are determined. Therefore, the laser processing apparatus 1 can perform laser processing on the object 11 based on the second processing conditions 260 determined by the second condition determination unit 65. In addition, the adjustment unit 66 of the laser processing apparatus 1 can adjust the second processing conditions 260 based on the results of laser processing of the object 11 by the laser processing apparatus 1, for example, if the amount of crack propagation 13 is insufficient. As an example, the results of laser processing of the object 11 can be obtained by an imaging device (not shown) of the laser processing apparatus 1, which images the object 11 with light transmitted through the object 11, and then detects the tip of the crack 13 inside the object 11 based on the image obtained from the imaging to measure the processing state.

[0083] As described above, in the laser processing apparatus 1 (laser processing system 100) and laser processing method according to this embodiment, first, the thickness of the object 11 (wafer thickness 201), processing information including at least one of the processing time for laser processing (processing time 202, 203) (for example, the processing time required to process the object 11), and processing quality for laser processing (quality level 204) is received. Subsequently, a processing type 210 for laser processing corresponding to the received processing information is determined. Next, a first processing condition 220, which is the standard processing condition for laser processing, is determined based on the received thickness of the object 11 and the determined processing type 210. Then, a second processing condition 260 including this first processing condition 220 is determined. In other words, according to the laser processing apparatus 1 (laser processing system 100) and laser processing method according to this embodiment, a processing type 210 that conforms to the user's requests (input) regarding processing time and processing quality is determined, and a second processing condition 260 based on the processing type 210 is determined. Therefore, processing conditions can be set to suit your needs.

[0084] By the way, when determining the type of laser processing 210 according to processing time and processing quality, it is desirable to control the amount of crack elongation from the modified region 12, for example, by increasing the amount of crack elongation from the modified region 12 in processing types 210 that prioritize increasing the cycle time (for example, the second processing type 212 or the third processing type 213), or by decreasing the amount of crack elongation from the modified region 12 in processing types that prioritize improving processing quality (for example, the first processing type 211 or the second processing type 212). One way to control the amount of crack elongation from the modified region 12 is to adjust the aberration correction amount of the laser beam L at each processing position inside the object 11.

[0085] Therefore, in the laser processing apparatus 1 (laser processing system 100) and laser processing method according to this embodiment, the first processing condition 220, which is determined according to the processing type 210, includes a plurality of processing positions 221 in the Z direction corresponding to the thickness of the object 11, and a type of aberration correction curve associated with each of the plurality of processing positions 221, and the aberration correction amount is calculated using these types of aberration correction curves. The second processing condition 260 is then determined including the calculated aberration correction amount. Thus, processing conditions that can control the amount of crack elongation 13 are suitably set according to the processing type 210 that meets the requirements for processing time and processing quality.

[0086] Furthermore, in the laser processing apparatus 1 (laser processing system 100) according to this embodiment, laser processing includes irradiating the object 11 with laser light L to form a modified region 12, and then cutting the object 11 using the modified region 12. The processing quality includes the bending strength of the cut piece 11p obtained by cutting the object 11, the damage caused by the incident laser light L on the back surface of the object 11, the amount of meandering of the modified region 12 when viewed from the Z direction, the straightness of the cut surface 11s of the cut piece 11p, and at least one of other quantities or properties related to arbitrary processing quality. Therefore, more optimal processing conditions can be set according to the various processing quality described above.

[0087] Furthermore, the laser processing apparatus 1 (laser processing system 100) according to this embodiment includes a display unit (input receiving unit 61) that displays at least a part of at least one of the first processing conditions 220 determined by the first condition determination unit 63 and the second processing conditions 260 determined by the second condition determination unit 65. Therefore, the user can easily confirm the processing conditions.

[0088] Furthermore, in the laser processing apparatus 1 (laser processing system 100) according to this embodiment, when the input receiving unit 61 displays the second processing conditions 260, at least the aberration correction amount 252 of the second processing conditions 260 may be hidden. The appropriate aberration correction amount according to the processing type 210 may include machine differences in the laser processing apparatus 1. Therefore, by not displaying the aberration correction amount 252 when displaying the second processing conditions 260, the user can confirm a certain processing condition regardless of the presence or absence of machine differences.

[0089] Furthermore, in the laser processing apparatus 1 (laser processing system 100) according to this embodiment, the input receiving unit 61 displays the processing position 221 as the internal position of the object 11. This makes it possible for the user to confirm the actual processing position inside the object 11.

[0090] Furthermore, the laser processing apparatus 1 (laser processing system 100) according to this embodiment performs laser processing of the object 11 based on the second processing conditions 260 determined by the second condition determination unit 65, and also includes an adjustment unit 66 that adjusts the second processing conditions 260 based on the results of the laser processing. Therefore, by adjusting the second processing conditions 260, more optimal processing conditions can be set.

[0091] Furthermore, in the laser processing apparatus 1 (laser processing system 100) according to this embodiment, the processing type 210 includes a first processing type 211, a second processing type 212, and a third processing type 213. The first processing type 211 is a processing type 210 in which the number of layers of modified regions 12 (modified layers 120) stacked in the Z direction within a certain thickness range of the object 11 is greater than the number of layers of modified layers 120 in the second processing type 212 and the third processing type 213. The second processing type 212 is a processing type in which the number of layers of modified layers 120 is less than that of the first processing type 211 and greater than that of the third processing type 213. The third processing type 213 is a processing type in which the number of layers of modified layers 120 is less than that of the first processing type 211 and the second processing type 212. By using such processing types, it is possible to reliably determine the processing type 210 in accordance with the user's requirements for processing time and processing quality.

[0092] Furthermore, in the laser processing apparatus 1 (laser processing system 100) according to this embodiment, the type determination unit 62 may determine a first processing type 211 as the processing type 210 when the processing information received by the input reception unit 61 includes processing time and the processing time is a first time (e.g., low speed), determine a second processing type 212 as the processing type 210 when the processing time is a second time shorter than the first time (e.g., medium speed), and determine a third processing type 213 as the processing type 210 when the processing time is a third time shorter than both the first and second times (e.g., high speed). In this case, it becomes possible to determine a processing type 210 that is in accordance with the processing time request from the user.

[0093] Furthermore, the laser processing apparatus 1 (laser processing system 100) according to this embodiment includes a database 67 that holds a plurality of processing types 210. The type determination unit 62 can determine the processing type 210 by referring to the database 67 and selecting a processing type 210 corresponding to the processing information received by the input reception unit 61 from the plurality of processing types 210 held in the database 67. Therefore, the processing type 210 can be easily determined by referring to the database 67.

[0094] Furthermore, in the laser processing apparatus 1 (laser processing system 100) according to this embodiment, the database 67 holds a plurality of first processing conditions 220 associated with each of the plurality of processing types 210, and the first condition determination unit 63 can determine the first processing conditions 220 by referring to the database 67 and selecting the first processing conditions 220 corresponding to the thickness of the object 11 received by the input reception unit 61 from among the plurality of first processing conditions 220 associated with the processing type 210 determined by the type determination unit 62. For this reason, the first processing conditions 220 can be easily determined by referring to the database 67.

[0095] Furthermore, the laser processing apparatus 1 (laser processing system 100) according to this embodiment includes a database 67 that holds multiple types of aberration correction curves. The correction amount calculation unit 64 can select an aberration correction curve included in the first processing condition 220 by referring to the database 67, and calculate the aberration correction amount using the selected aberration correction curve. In this case, by referring to the database 67, the aberration correction curve can be easily determined (selected), and the aberration correction amount can be calculated.

[0096] The embodiments described above illustrate one aspect of the present disclosure. Therefore, the present disclosure is not limited to the embodiments described above and can be modified as appropriate.

[0097] For example, in the above embodiment, the case was described in which the input receiving unit 61 displays a part of the second processing condition 260 after the second condition determination unit 65 has determined the second processing condition 260 in process S105. However, the input receiving unit 61 may display all of the second processing condition 260, or it may display the first processing condition 220 after the first condition determination unit 63 has determined the first processing condition 220 in process S103 and before process S104 or process S105. In this case, the input receiving unit 61 can display part or all of the first processing condition 220. That is, the input receiving unit 61 can display at least a part of the first processing condition 220 and the second processing condition 260.

[0098] Furthermore, in the above embodiment, an example was given in which the laser processing apparatus 1 is equipped with a control unit 6, and each part of the control unit 6 performs the processing related to steps S101 to S105. However, if a laser processing system 100 is configured including multiple laser processing apparatuses 1, the system control unit of the laser processing system 100 may perform the processing related to at least some of the steps of the control unit 6 described above. For example, the system control unit of the laser processing system 100 may perform the processing related to all of the steps S101 to S105, and each laser processing unit (laser processing apparatus 1) may perform laser processing based on the second processing conditions 260 provided by the system control unit.

[0099] Furthermore, in the above embodiment, three processing types 210 were exemplified: a first processing type 211, a second processing type 212, and a third processing type 213. However, processing type 210 may also include other processing types, such as a fourth processing type. For example, in process S101, if the input receiving unit 61 receives a selection of "damage suppression" from the user among the processing quality (quality level 204), the type determination unit 62 may determine a fourth processing type, which is a processing concept that suppresses damage to the incident back surface (e.g., the second surface 11b) of the object 11 caused by the laser beam L.

[0100] In this case, when forming one or more of the multiple modified layers 120 on the incident back surface side, if the correction amount calculation unit 64 calculates the aberration correction amount using the aberration correction curve C21 corresponding to B full blurring, damage to the incident back surface due to laser beam L leakage tends to occur more easily. Therefore, the aberration correction amount may be calculated using the aberration correction curve C31 corresponding to C half blurring. In this case, when forming one or more of the multiple modified layers 120 on the incident surface (for example, the first surface 11a) side, as an example, the aberration correction amount can be calculated using the aberration correction curve C11 corresponding to A optimal correction, which can increase the amount of crack propagation in order to connect the crack 13 in the Z direction.

[0101] Thus, the processing type 210 can be arbitrarily created and selected according to the processing time, processing quality, or incidence pattern, etc.

[0102] Furthermore, in the above embodiment, a method was described in which the machining position inside the object 11 is converted into a Z-movement amount, and then the aberration correction amount for the Z-movement amount obtained by the conversion is calculated using an aberration correction curve. However, by storing a combination of a conversion formula between the machining position inside the object 11 and the Z-movement amount (for example, the conversion formula shown in graphs G1 to G3) and an aberration correction curve showing the relationship between the Z-movement amount and the aberration correction amount (for example, aberration correction curves C11, C21, C31), the aberration correction amount can be calculated directly from the machining position inside the object 11.

[0103] Alternatively, the first processing condition 220 may include a Z-axis movement amount instead of (or in addition to) the processing position within the object 11. In this case, the aberration correction amount can be calculated directly from the Z-axis movement amount included in the first processing condition 220.

[0104] Furthermore, although the above embodiment describes a configuration in which the processing type 210, the first processing conditions 220, and the aberration correction curves C11, C21, and C31 are stored in the same database 67, for example, the processing type 210 and the first processing conditions 220 may be stored in one database, and the aberration correction curves C11, C21, and C31 may be stored in separate databases.

[0105] 1... Laser processing device (laser processing unit), 6... Control unit, 11... Object, 12... Modified area, 13... Crack, 61... Input reception unit (input reception unit, display unit), 62... Type determination unit, 63... First condition determination unit, 64... Correction amount calculation unit, 65... Second condition determination unit, 66... ​​Adjustment unit, 67... Database (first database, second database), 100... Laser processing system, 120-127... Modified layer, 210... Processing type, 220... First processing condition, 260... Second processing condition.

Claims

1. A laser processing system for performing laser processing to form a modified region on an object by irradiating the object with laser light, comprising: an input receiving unit that receives input of processing information including the thickness of the object in the Z direction intersecting the incident surface of the laser light on the object, and at least one of the processing time and processing quality of the laser processing; a type determination unit that determines the type of laser processing according to the processing information received by the input receiving unit; a first condition determination unit that determines a first processing condition which is a standard processing condition for the laser processing based on the thickness received by the input receiving unit and the processing type determined by the type determination unit; a correction amount calculation unit that calculates the aberration correction amount of the laser light using an aberration correction curve that shows the relationship between the processing position of the laser processing in the Z direction and the aberration correction amount of the laser light; and a second condition determination unit that determines a second processing condition including the first processing condition determined by the first condition determination unit and the aberration correction amount calculated by the correction amount calculation unit, The laser processing system comprises the first processing conditions including a plurality of processing positions in the Z direction corresponding to the thickness, and a type of aberration correction curve associated with each of the plurality of processing positions, and the correction amount calculation unit calculates the aberration correction amount for each of the plurality of processing positions based on the first processing conditions, using the type of aberration correction curve corresponding to each of the processing positions.

2. The laser processing system according to claim 1, wherein the laser processing includes irradiating the object with the laser light to form the modified region, and then cutting the object using the modified region, and the processing quality includes at least one of the flexural strength of the cut piece obtained by cutting the object, damage to the surface of the object on the side opposite to the incident surface by the laser light, the amount of meandering of the modified region when viewed from the Z direction, and the straightness of the cut surface of the cut piece.

3. The laser processing system according to claim 1 or 2, further comprising a display unit that displays at least a portion of at least one of the first processing conditions determined by the first condition determination unit and the second processing conditions determined by the second condition determination unit.

4. The laser processing system according to claim 3, wherein when the display unit displays the second processing conditions, at least the aberration correction amount among the second processing conditions is not displayed.

5. The laser processing system according to claim 3 or 4, wherein the display unit displays the processing position as the internal position of the object.

6. A laser processing system according to any one of claims 1 to 5, comprising: a laser processing unit that performs laser processing of the object based on the second processing conditions determined by the second condition determination unit; and an adjustment unit that adjusts the second processing conditions based on the results of the laser processing of the object by the laser processing unit.

7. The laser processing system according to any one of claims 1 to 6, wherein the processing type includes a first processing type, a second processing type, and a third processing type, the first processing type is a processing type in which the number of layers of the modified region stacked in the Z direction within a certain thickness range of the object is greater than the number of layers of the second processing type and the third processing type, the second processing type is a processing type in which the number of layers is less than the number of layers of the first processing type and greater than the third processing type, and the third processing type is a processing type in which the number of layers is less than the number of layers of the first processing type and the second processing type.

8. The laser processing system according to claim 7, wherein the type determination unit determines the first processing type as the processing type when the processing information received by the input receiving unit includes the processing time and the processing time is a first time; the type determination unit determines the second processing type as the processing type when the processing information received by the input receiving unit includes the processing time and the processing time is a second time which is shorter than the first time; and the type determination unit determines the third processing type as the processing type when the processing information received by the input receiving unit includes the processing time and the processing time is a third time which is shorter than both the first and second times.

9. A laser processing system according to any one of claims 1 to 8, comprising a first database that holds at least a plurality of processing types, wherein the type determination unit determines the processing type by referring to the first database and selecting the processing type corresponding to the processing information received by the input receiving unit from the plurality of processing types held in the first database.

10. The laser processing system according to claim 9, wherein the first database holds a plurality of first processing conditions associated with each of the plurality of processing types, and the first condition determination unit determines the first processing conditions by referring to the first database and selecting from the plurality of first processing conditions associated with the processing type determined by the type determination unit, the first processing condition corresponding to the thickness received by the input receiving unit.

11. A laser processing system according to any one of claims 1 to 10, comprising a second database that holds multiple types of aberration correction curves, wherein the correction amount calculation unit selects an aberration correction curve included in the first processing conditions by referring to the second database, and calculates the aberration correction amount using the selected aberration correction curve.

12. A laser processing method for performing laser processing to form a modified region on an object by irradiating the object with laser light, comprising: an input receiving step for receiving input of processing information including the thickness of the object in the Z direction intersecting the incident surface of the laser light on the object, and at least one of the processing time and processing quality of the laser processing; a type determination step for determining the type of laser processing according to the processing information received in the input receiving step; a first condition determination step for determining a first processing condition which is a standard processing condition for the laser processing, based on the thickness received in the input receiving step and the processing type determined in the type determination step; a correction amount calculation step for calculating the aberration correction amount of the laser light using an aberration correction curve showing the relationship between the processing position of the laser processing in the Z direction and the aberration correction amount of the laser light; and a second condition determination step for determining a second processing condition which includes the first processing condition determined in the first condition determination step and the aberration correction amount calculated in the correction amount calculation step, A laser processing method comprising: the first processing conditions include a plurality of processing positions in the Z direction corresponding to the thickness, and a type of aberration correction curve associated with each of the plurality of processing positions; and the correction amount calculation step calculates the aberration correction amount for each of the plurality of processing positions based on the first processing conditions, using the type of aberration correction curve corresponding to each of the processing positions.

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