TW201411706A - Cutting method for item to be processed, item to be processed and semiconductor element - Google Patents

Abstract

The invention sets cut plan lines (51, 52) for cutting an item to be processed (1) such that neither of said cut plan lines (51, 52) is parallel to an a-plane or an m-plane of a hexagonal crystalline compound. A laser beam (L) is irradiated following the cut plan lines (51, 52) that were set in said manner, forming reforming areas (71, 72), and the item to be processed (1) is cut with the reforming areas (71, 72) as a starting point. By means of this procedure, the item to be processed (1) is capable of being cut and a semiconductor element (10) manufactured, while reducing an effect of the crystal structure of the hexagonal crystalline compound, which composes a substrate (31).

Description

Process object cutting method, object to be processed, and semiconductor element

The present invention relates to a method of cutting an object to be processed, a workpiece, and a semiconductor element, which are used for cutting a semiconductor object.

In the conventional method of cutting an object to be processed in the above-described technical field, Patent Document 1 describes that a separation groove is formed on the front and back surfaces of a sapphire substrate by square cutting and scribe lines, and is irradiated by laser light. In the sapphire substrate, a method of cutting the sapphire substrate along the separation groove and the processing and modifying portion is formed in a plurality of stages.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2006-245043

However, in order to crystallize the hexagonal crystals of the above-described sapphire or the like The composition of the substrate and the substrate on which the c-plane of the hexagonal compound is offset by an off-angle is cut, and has a surface and a back surface of the substrate and a hexagonal compound. The line to be cut parallel to the surface and the line to cut parallel to the front and back surfaces of the substrate and the m-plane of the hexagonal compound are set in the object to be processed. In such a case, when the object to be processed is cut by using the modified light field formed in the substrate as a starting point along the respective cutting lines, the crystal structure of the hexagonal compound may affect the cutting. Case.

In view of the above, it is an object of the present invention to provide a method for cutting a workpiece, a workpiece, and a semiconductor element, and to cut off the object to be processed by suppressing the influence of the crystal structure of the hexagonal compound. .

The present invention relates to a method of cutting an object to be processed. This method of cutting an object to be processed is a method of cutting a workpiece, and is characterized in that it includes a first process of preparing an object to be processed, and the object to be processed has a hexagonal compound and is contained therein. a substrate including a front surface and a back surface at an angle different from a c-plane of the hexagonal compound; and a plurality of semiconductor element portions arranged in a matrix along the first and second directions on the surface of the substrate; and The light collecting point of the laser light is aligned in the substrate, and the light collecting point is set along the plurality of first cutting planned lines set in the first direction by the manner between the adjacent semiconductor element portions. Relatively moving, each forming a first change in the substrate along the first line to cut a second process in the field of mass; and aligning the light collecting points of the laser light in the substrate by the plurality of the semiconductor element portions that are adjacent to each other along the second direction (2) cutting the predetermined line to relatively move the light collecting point, respectively forming a third process of the second modified field in the substrate along the second cutting planned line; and separately cutting along the first and second sides The predetermined line is applied to the object to be processed, and the first and second modified areas are used as the starting point, and the object to be processed is cut along the first and second cutting lines, and the semiconductor including the semiconductor element portion is cut. The fourth process of manufacturing the device; the first direction is parallel to the front surface and the back surface of the substrate, and intersects with the a-plane and the m-plane of the hexagonal compound, and the second direction is parallel to the surface and the back surface of the substrate. And, the direction perpendicular to the first direction.

In this method of cutting an object to be processed, first, an object to be processed is prepared. The object to be processed is composed of a hexagonal compound, and includes a substrate having a front and back surfaces having an angle deviated from the c-plane, and a plurality of semiconductor element portions formed on the surface of the substrate. The semiconductor element portion is parallel to the front and back surfaces of the substrate, and is along the first direction intersecting the a-plane and the m-plane of the hexagonal compound, and the second parallel to the front and back of the substrate and perpendicular to the first direction. Directions are arranged in a matrix. In addition, the line to be cut for cutting the object to be processed is set along the first direction and the second direction by the manner between the adjacent semiconductor element portions. That is, the predetermined line to be cut is set so as not to be parallel to the a-plane and the m-plane of the hexagonal compound. In the method of cutting the object to be processed, the laser beam is irradiated along the line to be cut thus set to form a modified region, and the object to be processed is cut as a starting point. Therefore, according to According to the method of cutting the object to be processed, it is possible to cut the object to be processed and to manufacture the semiconductor element by suppressing the influence of the crystal structure of the hexagonal compound constituting the substrate. Also, the off angle is a case where 0° is included. In this case, the front and back surfaces of the substrate are parallel to the c-plane of the hexagonal compound.

In the object cutting method according to the present invention, in the second process, the back surface of the substrate is used as the incident surface of the laser light, and the first crack generated from the first modified region reaches the back surface of the substrate, and is in the third In the process, the back surface of the substrate is used as the incident surface of the laser light, and the second crack generated from the second modified region reaches the back surface of the substrate. In the fourth process, an external force is applied to the external force. In the object to be processed, the first and second cracks can be stretched to cut the object to be processed. In this case, when the modified region is formed inside the substrate, the influence of the laser light on the semiconductor element portion can be suppressed.

Here, another invention of the present invention relates to an object to be processed. The object to be processed is composed of a hexagonal compound and includes a substrate having a surface and a back surface at an angle different from a c-plane of the hexagonal compound, and a plurality of semiconductors formed on the surface of the substrate. The element portion is characterized in that the plurality of semiconductor element portions are parallel to the surface and the back surface of the substrate, intersect with the a-plane and the m-plane of the hexagonal compound, and are parallel to the front and back surfaces of the substrate. The second direction perpendicular to the first direction is arranged in a matrix.

In the object to be processed, the line to be cut for cutting the object to be processed can be set so as not to be parallel to the a-plane and the m-plane of the hexagonal compound, as described above. And along the cutting schedule thus set When the line is irradiated with the laser light to form a modified region, and the object to be processed is cut off as the starting point, the semiconductor element can be cut by suppressing the influence of the crystal structure of the hexagonal compound constituting the substrate.

Further, the present invention is directed to a semiconductor element. The semiconductor device is composed of a hexagonal compound and has a base portion and a back surface portion which are at an angle different from the c-plane of the hexagonal compound, and a semiconductor element portion formed on the surface of the base portion. The semiconductor device is characterized in that the base portion has a pair of first side faces that connect the front surface and the back surface and face each other, and a pair of second side faces that connect the front surface and the back surface and are perpendicular to the first side surface, The side faces of the first side are intersected with the a-plane and the m-plane of the hexagonal compound. In this case, it is possible to suppress the crystal structure of the hexagonal compound constituting the base from affecting the element characteristics.

Here, the hexagonal crystal compound may be a single crystal sapphire, and the semiconductor element portion may be a light-emitting element portion for generating light.

According to the present invention, it is possible to provide a method for cutting an object to be processed, an object to be processed, and a semiconductor element, which are capable of suppressing the influence of the crystal structure of the hexagonal compound.

L‧‧‧Laser light

OF‧‧‧ Orientation plane

P‧‧‧Light spot

X1‧‧‧ axis (1st direction)

X2‧‧‧ axis (2nd direction)

1‧‧‧Processing objects

5‧‧‧ cut the booking line

7‧‧‧Change field

8‧‧‧ cut off starting area

10‧‧‧Lighting elements (semiconductor components)

31‧‧‧Substrate (base)

31a‧‧‧ surface

31b‧‧‧Back

31c‧‧‧ side (1st side)

32‧‧‧Light-emitting device unit (semiconductor device unit)

32c‧‧‧ side (2nd side)

34‧‧‧Semiconductor layer

35‧‧‧Semiconductor layer

41‧‧‧Protective zone

42‧‧‧Retractable tape

43‧‧‧Receiving components

44‧‧‧ knife edge

51, 52‧‧‧ cut the booking line

71,72‧‧‧Change field

81,82‧‧‧ cracks (1st, 2nd crack)

100‧‧‧ Laser processing equipment

101‧‧‧Laser light source

102‧‧‧Laser Light Source Control Department

103‧‧‧ dichroic mirror

105‧‧‧Light collecting lens

107‧‧‧Support table

111‧‧‧ stage

115‧‧‧Station Control Department

[Fig. 1] The laser processing apparatus used in the formation of the field of reforming A schematic diagram.

[Fig. 2] A plan view of an object to be processed which is a target of formation in the field of reformation.

[Fig. 3] A cross-sectional view taken along line III-III of the object to be processed as shown in Fig. 2 .

[Fig. 4] A plan view of an object to be processed after laser processing.

[Fig. 5] A cross-sectional view taken along line V-V of the object to be processed as shown in Fig. 4.

[Fig. 6] A cross-sectional view taken along line VI-VI of the object to be processed as shown in Fig. 4.

[Fig. 7] A plan view of an object to be processed in a method of cutting an object to be processed according to an embodiment of the present invention.

[Fig. 8] A unit cell diagram showing the crystal structure of the hexagonal compound in the object to be processed shown in Fig. 7.

[Fig. 9] A partial cross-sectional view of the object to be processed as shown in Fig. 7.

[Fig. 10] Fig. 10 is a partial cross-sectional view showing the main process of the object cutting method according to the embodiment of the present invention.

[Fig. 11] Fig. 11 is a partial cross-sectional view showing the main process of the object cutting method according to the embodiment of the present invention.

[Fig. 12] Fig. 12 is a partial cross-sectional view showing the main process of the object cutting method according to the embodiment of the present invention.

[Fig. 13] Fig. 13 is a perspective view of a light-emitting element obtained by the object cutting method according to the embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the respective drawings, the same reference numerals are given to the same or corresponding parts, and the repeated description is omitted.

In the object cutting method according to the embodiment of the present invention, the laser beam is irradiated onto the object to be processed along the line to be cut, and a modified region is formed inside the object along the line to cut. Here, first, the formation of this modified field will be described with reference to FIGS. 1 to 6 .

As shown in Fig. 1, the laser processing apparatus 100 includes a laser beam 101 that oscillates the laser beam L and a dichroic mirror that arranges the direction of the optical axis (optical path) of the laser beam L by 90°. 103. A light collecting lens 105 for collecting laser light L. Further, the laser processing apparatus 100 includes a support table 107 for supporting the object 1 to be irradiated by the laser light L collected by the light collecting lens 105, and a stage 111 for moving the support table 107. And a laser light source control unit 102 that controls the laser light source 101 and a stage control unit 115 that controls the movement of the stage 111 in order to adjust the output of the laser light L and the pulse width.

In the laser processing apparatus 100, the laser light L emitted from the laser light source 101 is changed by 90 degrees by the dichroic mirror 103, and is collected by the collecting lens 105. The inside of the object 1 to be placed on the support table 107 is placed. At the same time, the stage 111 is moved so that the object 1 is opposed to the laser light L along the line to cut 5 mobile. Thereby, the modified region along the line to cut 5 is formed in the object 1 to be processed.

As shown in FIG. 2, in the object 1 to be processed, a planned cutting line 5 for cutting the object 1 is set. The line to cut 5 is a broken line extending in a straight line. In the case where the modified region is formed inside the object 1 to be processed, as shown in FIG. 3, the laser light L is placed along the line to cut in a state where the light collecting point P is aligned inside the object 1 5 (that is, the direction of the arrow A in Fig. 2) relatively moves. As a result, as shown in FIG. 4 to FIG. 6, the modified field 7 is formed inside the object 1 along the line to cut 5, and the modified field 7 formed along the line to cut 5 becomes Cut off the starting point area 8.

Further, the light collecting point P refers to the light collecting portion of the laser light L. Further, the line to cut 5 is not limited to a linear curved shape, and may be a line that is actually drawn on the surface 3 of the object 1 without being limited to a broken line. Moreover, the field of upgrading 7 is also formed continuously, and there are cases where it is formed intermittently. Further, the modified field 7 may be in the form of a column or a dot, that is, the modified region 7 may be formed at least inside the object 1 to be processed. Further, in the case where the crack is formed starting from the modified region 7, the crack and the modified region 7 may expose the outer surface (surface, back surface, or outer peripheral surface) of the object 1 to be processed.

By the way, the laser light L is absorbed through the object 1 and in particular in the vicinity of the light collecting point inside the object 1, whereby the object 1 is formed with the modified field 7 ( That is, internal absorption type laser processing). Therefore, in the surface 3 of the object 1 for processing Since the laser light L is hardly absorbed, the surface 3 of the object 1 does not melt. In general, the surface 3 is melted and removed to form a removal portion (surface absorption type laser processing) such as a hole or a groove, and the processing area is gradually performed from the surface 3 side toward the back surface side.

However, in the field of reforming formed in the present embodiment, it means that the density, the tortuosity, the mechanical strength, and other physical properties are areas which are different from the surroundings. The field of reforming is, for example, a field of melt processing, a field of cracking, a field of dielectric breakdown, a field of change in tortuosity, and the like, and there are also fields in which these are mixed. Further, the field of reforming also has a field in which the material of the object to be processed changes the density in the field of modification and a density in the field of non-modification, and a case in which lattice defects are formed (these are also collectively referred to as a high-density transfer field). .

And the field of melt processing and the field of tortuosity change, the field of density change in the field of modification and the density of non-metaplastic field, and the field of lattice defects are further in the field of internal and upgrading areas and non-reform In the case of a crack in the interface (rupture, microcracking). The cracked inside is a situation that has a comprehensive situation across the field of reformation and only a part of the formation and the plural part are formed.

Further, in the present embodiment, the modified region 7 is formed by forming a plurality of modified beam spots (machining marks) along the line to cut 5 . The modified beam spot refers to a modified portion formed by one pulse of pulsed laser light (that is, one-pulse laser irradiation: laser irradiation), and becomes a modified field 7 by collecting modified beam spots. The modified beam spot can be exemplified by a crack beam spot, a melt processing beam spot or a tortuosity change beam spot, or at least two of these. In the case.

For the modified beam spot, the size of the crack and the length of the crack generated are appropriately controlled in consideration of the required cutting accuracy, the required flatness of the cut section, the thickness, type, and crystal orientation of the object to be processed. Preferably.

Next, a method of cutting an object to be processed according to an embodiment of the present invention will be described. Fig. 7 is a plan view of the object to be processed to which the object cutting method of the present embodiment is applied. Fig. 8 is a view showing a crystal structure of a material of a substrate constituting the object to be processed shown in Fig. 7. Fig. 9 is a partial cross-sectional view of the object to be processed as shown in Fig. 7. In particular, Fig. 9(a) is a cross-sectional view taken along the axis x1 of Fig. 7, and Fig. 9(b) is a cross-sectional view taken along the axis x2 of Fig. 7. As shown in FIGS. 7 to 9, the object 1 is a wafer having a disk 31 having a disk shape (for example, a diameter of 2 to 6 inches and a thickness of 50 to 200 μm).

The substrate 31 is composed of a hexagonal compound (here, single crystal sapphire) having a hexagonal crystal structure. In the substrate 31, the c-axis of the hexagonal compound is only inclined at an angle θ (for example, 0.1°) with respect to the thickness direction of the substrate 31. That is, the substrate 31 is an off angle having an angle θ. More specifically, the substrate 31 is a surface 31a and a back surface 31b which are formed to have an angle θ which is deviated from the c-plane of the hexagonal compound. In the substrate 31, the m-plane of the hexagonal compound has an inclination angle θ with respect to the thickness direction of the substrate 31, and the a-plane of the hexagonal compound is parallel to the thickness direction of the substrate 31.

The object 1 is a plurality of light-emitting element portions (semiconductor element portions) 32 formed on the surface 31a of the substrate 31. The light-emitting element portion 32 is arranged in a matrix on the surface 31a of the substrate 31 along the direction of the axis x1 (first direction) and the direction of the axis x2 (second direction). The axis x1 is an axis parallel to the surface 31a and the back surface 31b of the substrate 31 and along a direction intersecting the a-plane and the m-plane of the hexagonal compound. The angle of intersection of the a-plane and the axis x1 of the hexagonal compound It is, for example, about 45 degrees.

The axis x2 is an axis parallel to the surface 31a and the back surface 31b of the substrate 31 and in a direction substantially perpendicular to the direction of the axis x1. Therefore, the axis x2 is also parallel to the surface 31a and the back surface 31b of the substrate 31, and intersects the a-plane and the m-plane of the hexagonal compound. The intersection angle of the m-plane and the axis x2 of the hexagonal compound It is, for example, about 45 degrees. In other words, the light-emitting element portion 32 is arranged along the surface x1 and the back surface 31b of the substrate 31 along the directions of the axis x1 and the axis x2 which are rotated by about 45 degrees from the a-plane and the m-plane of the hexagonal compound.

Therefore, the arrangement direction of the light-emitting element portions 32 is not parallel (not along) with any of the a-plane and the m-plane of the hexagonal compound. In the object 1 to be processed, the orientation plane OF is set so as to be parallel to the a-plane of the hexagonal compound. Therefore, the light-emitting element portions 32 are arranged in a direction that is not parallel (not along) with respect to this orientation plane.

As shown in FIG. 9, the light-emitting element portion 32 thus arranged has a semiconductor layer 34 laminated on the surface 31a of the substrate 31, and a semiconductor layer 35 laminated on the semiconductor layer 34. semiconductor The layer 34 has a first conductivity type (for example, an n-type). The semiconductor layer 34 is continuously formed across all of the light-emitting element portions 32. The semiconductor layer 35 has a second conductivity type (for example, p-type) different from the first conductivity type. The semiconductor layer 35 is formed in an island shape in which the respective light-emitting element portions 32 are separated. The semiconductor layers 34 and 35 are made of a group III-V compound semiconductor such as GaN, and are bonded to each other by pn.

Further, in the object 1 to be processed, a plurality of directions are set along the direction of the axis x1 so as to pass between the adjacent light-emitting element portions 32 and 32 (more specifically, between the adjacent semiconductor layers 35 and 35). The planned cutting line (first cutting planned line) 51 is cut, and a plurality of predetermined cutting lines (second cutting planned lines) 52 are set along the direction of the axis x2. The planned cutting lines 51 and 52 are each extended so as not to be parallel (not along) to the a-plane and the m-plane of the hexagonal compound.

Next, the object to be processed 1 is cut into the respective light-emitting element portions 32 to cut the object to be processed for manufacturing the plurality of light-emitting elements (semiconductor elements). In the method of cutting an object to be processed, first, the object 1 to be processed described above is prepared (first process). In addition, after the protective tape 41 is attached so as to cover the light-emitting element portion 32, the object to be processed 1 is placed on the support table 107 of the above-described laser processing apparatus 100 through the protective tape 41. Upper (references in Figures 1 and 10).

Next, as shown in FIG. 10(a), the back surface 31b of the substrate 31 is used as the incident surface of the laser light L in the substrate 31, and the light collecting point P of the laser light L is aligned in the substrate 31, respectively. Cutting the predetermined line 51 so that The collection point P moves relatively. Thereby, the modified region (first modified region) 71 is formed in the substrate 31 along the line to cut 51 (that is, along the axis x1 intersecting the a-plane and the m-plane), and the field of modification is made. The crack (first crack) 81 generated at 71 reaches the back surface 31b of the substrate 31 (second process). At this time, although the crack 81 does not reach the surface 31a of the substrate 31, it extends from the modified region 71 toward the surface 31a side.

Next, as shown in FIG. 10(b), the back surface 31b of the substrate 31 is used as the incident surface of the laser light L in the substrate 31, and the light collecting point P of the laser light L is aligned in the substrate 31, respectively. The cut line 52 is moved to relatively move the light collecting point P. Thereby, the modified region (second modified region) 72 is formed in the substrate 31 along the line to cut 52 (that is, along the axis x2 intersecting the a-plane and the m-plane), and the field of modification is made. The crack (second crack) 82 generated at 72 reaches the back surface 31b of the substrate 31 (third process). At this time, although the crack 82 does not reach the surface 31a of the substrate 31, it extends from the modified region 72 toward the surface 31a side.

When the modified regions 71 and 72 are formed inside the substrate 31 along the cutting lines 51 and 52 which are not parallel to the a-plane and the m-plane of the hexagonal compound, the modified regions 71 and 72 are used for the modified regions 71 and 72. The cutting of the object 1 at the starting point can suppress the influence of the crystal structure of the hexagonal compound constituting the substrate 31 (especially the influence of the r-plane of the hexagonal compound).

Further, the modified regions 71 and 72 formed in the substrate 31 are those including the field of melt processing. Further, the crack 81 occurring from the modified field 71 and the crack 82 occurring from the modified field 72 are by the laser light L The irradiation conditions are appropriately adjusted to reach the back surface 31b of the substrate 31. The irradiation condition of the laser light L for the cracks 81 and 82 to reach the back surface 31b is, for example, a distance from the rear surface 31b at a position where the light collecting point P of the laser light L is aligned, and a pulse width of the laser light L. The pulse pitch of the laser light L (the value of "the moving speed of the light collecting point P of the laser light L of the object 1 to be processed" is "the value of the laser light L", the pulse energy of the laser light L, and the like.

Next, a method of cutting the object to be processed will be described. In the subsequent process, an external force is applied to the object 1 by the respective cutting lines 51 and 52, and the reformed fields 71 and 72 formed are used as the starting point by the above-described process, and each of them is cut off. The predetermined lines 51 and 52 cut the object 1 into the respective light-emitting element portions 32 (fourth process). More specifically, in the process, first, as shown in FIG. 11, the stretchable tape 42 is attached to the object 1 after the back surface 31b of the substrate 31 is covered, and is processed through the stretchable tape 42. The object 1 is placed on the receiving member 43 of the three-point bending and cutting device.

As shown in Fig. 11(a), the blade edge 44 is brought into contact with the object 1 through the protective tape 41 from the side of the surface 31a of the substrate 31 along the line to cut 51, respectively. The cutting planned line 51 applies an external force to the object 1 to be processed. As a result, the crack 81 generated from the modified region 71 is extended toward the surface 31a side of the substrate 31, and the object 1 is cut into a rod shape along the line to cut 51.

Next, as shown in FIG. 11(b), the protective tape 41 is transmitted from the surface 31a side of the substrate 31 by the respective cutting line 52. The blade edge 44 is brought into contact with the object 1 to be processed, and an external force is applied to the object 1 along the line to cut 52. As a result, the crack 82 generated from the modified region 72 is extended toward the surface 31a side of the substrate 31, and the object 1 is cut into a wafer shape along the line to cut 52.

In the subsequent process, after the object 1 is cut, as shown in Fig. 12, the protective tape 41 is removed from the object 1 and the stretchable tape 42 is expanded outward. Thereby, the plurality of light-emitting elements (semiconductor elements) 10 obtained by cutting the object 1 into a wafer shape are separated from each other.

The light-emitting element 10 thus obtained has a substantially square shape as shown in Fig. 13 . Further, the light-emitting element 10 is composed of a hexagonal compound (here, single crystal sapphire) and has a surface 31a and a back surface 31b which are provided with an angle θ which is off-angled from the c-plane of the hexagonal compound. The base portion 31 (substrate 31) and the light-emitting element portion 32 formed on the surface 31a of the base portion.

The base portion 31 has a pair of side surfaces (first side faces) 31c that connect the front surface 31a and the back surface 31b and face each other, and a pair of side faces that connect the front surface 31a and the back surface 31b and are perpendicular to the side surface 31c (second Side) 32c. The side surface 31c is, for example, a cross section formed when the object 1 is cut along the line to cut 51. The side surface 32c is, for example, a cross section formed when the object 1 is cut along the line to cut 52. Therefore, each of the side faces 31c and 32c of the base portion 31 extends in a direction intersecting the a-plane and the m-plane of the hexagonal compound constituting the base portion 31 (that is, not parallel to the a-plane and the m-plane).

As described above, in the object cutting method of the present embodiment, first, the object 1 is prepared. The object 1 to be processed is composed of a hexagonal compound, and includes a substrate 31 having a surface 31a and a back surface 31b which are inclined at an angle θ from the c-plane, and a surface formed on the substrate 31. The plurality of light-emitting element portions 32 on 31a. The light-emitting element portion 32 is parallel to the surface 31a and the back surface 31b of the substrate 31, and is parallel to the axis x1 intersecting the a-plane and the m-plane of the hexagonal compound, and parallel to the surface 31a and the back surface 31b of the substrate 31. The direction of the axis x2 perpendicular to the axis x1 is arranged in a matrix.

The line to cut 51 and the line to cut 52 for cutting the object 1 are formed so as to pass between the adjacent light-emitting element portions 32 and 32 along the axis x1 and the axis x2. The direction is set. In other words, in the object cutting method, the predetermined lines 51 and 52 are cut so as not to be parallel to the a-plane and the m-plane of the hexagonal compound. In the processed object cutting method, the laser beam L is irradiated along the cut lines 51 and 52 thus set to form the modified regions 71 and 72, and the modified regions 71 and 72 are used as the starting points. The object to be processed 1 is cut. Therefore, according to the object cutting method, the influence of the crystal structure of the hexagonal compound constituting the substrate 31 (especially the influence of the r-plane of the hexagonal compound) can be suppressed, and the object 1 can be cut into The light-emitting element 10 is manufactured by each of the light-emitting element portions 32.

In the object 1 to be processed of the present embodiment, the planned cutting lines 51 and 52 for cutting the object 1 can be set to the a-plane and the m-plane of the hexagonal compound, respectively, as described above. parallel. And along When the cutting target lines 51 and 52 are set to the laser beam L to form the modified areas 71 and 72, and the object to be processed 1 is cut off using the modified areas 71 and 72 as the starting point, the composition can be suppressed. The semiconductor element 10 is manufactured by cutting the object 1 under the influence of the crystal structure of the hexagonal compound of the substrate 31.

The above embodiment is an embodiment of the object cutting method, the object to be processed, and the semiconductor element of the present invention. Therefore, the object cutting method, the object to be processed, and the semiconductor element of the present invention are not limited to the above. The object cutting method, the object to be processed, and the semiconductor element of the present invention can be arbitrarily modified without changing the scope of the scope of the respective claims.

For example, the material of the substrate 31 constituting the object 1 is not limited to single crystal sapphire, and any hexagonal compound such as gallium nitride (for example, GaN) having a hexagonal crystal structure and niobium carbide (for example, SiC). Also.

The intersection angles of the respective axes x1 and x2 of the a-plane and the m-plane of the hexagonal compound constituting the substrate 31 of the object 1 to be processed (that is, the planned cutting line 51 and the planned cutting line 52) ψ, not limited to 45°, and may be 30° (-30°) and 60° (-60°).

The orientation flat OF in the object 1 is not limited to be parallel to the a-plane of the hexagonal compound constituting the substrate 31 of the object 1 , and is, for example, an axis intersecting the a-plane and the m-plane of the hexagonal compound. It is also possible to form x1 or the axis x2 in parallel.

Further, the object 1 to be processed can replace the light-emitting element portion 32. It is also possible to use a semiconductor element portion having any functional element.

[Industrial availability]

According to the present invention, it is possible to provide a method of cutting a workpiece, a workpiece, and a semiconductor element, and to cut the object to be processed by suppressing the influence of the crystal structure of the hexagonal compound.

OF‧‧‧ Orientation plane

1‧‧‧Processing objects

31‧‧‧Substrate (base)

31a‧‧‧ surface

32‧‧‧Light-emitting device unit (semiconductor device unit)

51‧‧‧ cut off the booking line

52‧‧‧ cut off the booking line

Claims (6)

A method of cutting an object to be processed, comprising: a first process of preparing an object to be processed, the object to be processed being composed of a hexagonal compound and having a c-plane containing the hexagonal compound a substrate on the front and back sides of the yaw angle and a plurality of semiconductor element portions arranged in a matrix along the first and second directions on the surface of the substrate; and a light collecting point pair of the laser light Positioned in the substrate, the light collecting point is relatively moved along the plurality of first cutting planned lines set in the first direction by the manner between the adjacent semiconductor element portions. a second process of forming a first modified region in the substrate along the first cutting line; and aligning the light collecting points of the laser light in the substrate, by passing adjacent Each of the semiconductor element portions is moved relative to each other along a plurality of second cutting planned lines set in the second direction, and each of the substrates is along the second cutting planned line. Forming the second modification field And a third process of applying the external force to the object to be processed along the first and second cutting lines, and using the first and second modified regions as starting points, respectively 1 and a second cutting line to cut the object to be processed, and a fourth process for manufacturing the semiconductor element including the semiconductor element portion; the first direction is parallel to the surface of the substrate and the back surface, and a side that intersects the a-plane and the m-plane of the hexagonal compound The second direction is a direction perpendicular to the surface of the substrate and the back surface, and perpendicular to the first direction. The method of cutting an object to be processed according to the first aspect of the invention, wherein, in the second process, the back surface of the substrate is used as an incident surface of the laser beam, and the first surface is generated from the first modified region. In the third process, the back surface of the substrate is used as the incident surface of the laser beam, and the second crack generated from the second modified region reaches the substrate. In the back surface, in the fourth process, the external object is applied to the object to be processed, and the first and second cracks are stretched to cut the object to be processed. The method of cutting an object to be processed according to claim 1 or 2, wherein the hexagonal crystal compound is a single crystal sapphire, and the semiconductor element portion is a light emitting element portion. An object to be processed, comprising: a hexagonal compound; and a substrate having a surface and a back surface at an angle different from a c-plane of the hexagonal compound; and a surface formed on the substrate The plurality of semiconductor element portions are characterized in that the plurality of semiconductor element portions are parallel to the surface and the back surface of the substrate and are a-plane and m of the hexagonal compound The first direction intersecting the surface and the second direction parallel to the surface and the back surface of the substrate and perpendicular to the first direction are arranged in a matrix. The object to be processed according to claim 4, wherein the hexagonal crystal compound is a single crystal sapphire, and the semiconductor element portion is a light emitting element portion. A semiconductor device comprising a hexagonal compound and having a base portion and a back surface which are at an angle different from a c-plane of the hexagonal compound, and a surface formed on the surface of the base portion The semiconductor element portion is characterized in that the base portion has a pair of first side faces that connect the front surface and the back surface and face each other, and a first surface that connects the front surface and the back surface and is perpendicular to the first side surface In the second side surface, the first side surface intersects the a surface and the m surface of the hexagonal compound.