TW201705243A - Method for manufacturing optical device chip - Google Patents

Abstract

Provided is a method for manufacturing an optical device chip, wherein the light extraction efficiency of the optical device chip can be increased. The method for manufacturing an optical device chip, whereby multiple optical device chips are manufactured by dividing an optical device wafer (11), comprises: a laser processing groove forming step of forming a pair of laser processing grooves (19), wherein a section perpendicular to a division line has a V-shape, on the rear side (11b) of an optical device wafer (11b) along the division line by radiating a laser beam (L1) with a wavelength absorbable with respect to the optical device wafer; a V-shaped groove forming step of crushing and removing the optical device wafer, which is present in a region between the pair of laser processing grooves, by using a cutting blade (14) and forming a V-shaped groove (21); a polishing step of polishing the inner wall surface of the V-shaped groove; and a division step of dividing the optical device wafer into respective optical device chips along respective division lines by generating cracks (25) between the V-shaped groove and the division lines.

Description

Optical element chip manufacturing method

The present invention relates to a method of manufacturing an optical element wafer to which a light-emitting type optical element wafer is manufactured.

In the production of a light-emitting diode such as a light-emitting diode (LED) or a laser diode (LD), the surface of a substrate for crystal growth made of sapphire or SiC is grown by epitaxial growth or the like. The method forms a luminescent layer. The substrate (optical element wafer) on which the light-emitting layer is formed is divided into a plurality of optical element wafers along a predetermined dividing line (cutting path).

As a method of dividing an optical element wafer, it is known that a laser beam having a high absorbability with respect to an optical element wafer is irradiated along a dividing line to form a laser processing groove due to ablation (for example, See Patent Document 1). The optical element wafer can be divided along the laser processing groove so that an external force is applied to the optical element wafer on which the laser processing groove is formed.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 10-305420

Incidentally, in the above-described light-emitting type optical element wafer, it is important to increase the light extraction efficiency as much as possible. However, for example, in the optical element wafer manufactured by the conventional method, it is possible to suppress the ratio of light which is totally reflected by the side surface of the substrate and is internally attenuated after being emitted onto the back surface side (substrate side) of the light-emitting layer. There is room for improvement in terms of light extraction efficiency.

The present invention has been made in view of the related problems, and an object thereof is to provide a method of manufacturing an optical element wafer which can improve light extraction efficiency of an optical element wafer.

According to the present invention, there is provided a method of manufacturing an optical element wafer in which light of an optical element including a light-emitting layer is formed in each of a plurality of areas defined by a plurality of predetermined dividing lines which are set on the surface and intersect each other. The component wafer is divided along the dividing line to produce a plurality of optical component wafers. The method includes a laser processing trench forming step of obliquely illuminating the back surface of the optical component wafer with respect to the optical component wafer. a laser beam having an absorptive wavelength, wherein a shape of a cross section orthogonal to the predetermined dividing line is a V-shape, and a laser processing groove is formed on a back side of the optical element wafer along the dividing line; Forming step, the laser is implemented After the processing groove forming step, the optical element wafer existing in the field between the pair of laser processing grooves is crushed and removed by a cutting insert to form a V shape corresponding to the shape of the pair of laser processing grooves. a V groove; a polishing step of polishing the inner wall surface of the V groove after the step of forming the V groove; and a dividing step of applying an external force to the optical element wafer after the polishing step is performed A crack is generated between the predetermined dividing line, and the optical element wafer is divided into one optical element wafer along each predetermined dividing line.

In the present invention, in the V-groove forming step, it is preferable to perform an up-cut method in a processing point where the optical element wafer is in contact with the cutting blade, and from the inside of the optical element wafer toward the back surface. Rotate the cutting insert in the direction.

Further, in the present invention, in the polishing step, it is preferable that the V groove is cut by a cutting insert having a V shape having a tip end corresponding to the V groove, and the inner wall surface of the V groove is polished.

Further, in the present invention, before the step of forming the laser processing groove, it is preferable to further include a step of forming a reforming layer to irradiate a laser beam having a wavelength transparent to the optical element wafer. The optical element wafer forms a guiding reforming layer for guiding the crack along the dividing line in the dividing step.

In the method of manufacturing an optical element wafer according to the present invention, a V-groove having a V-shaped cross section is formed along a line to be divided. On the back side of the optical element wafer, an external force is applied to the optical element wafer into one optical element wafer, and the side surface on the back side of the completed optical element wafer is formed on the surface side. The light elements of the luminescent layer are tilted.

As a result, for example, in the optical element wafer from which the light is taken out from the surface side, light emitted to the back surface side (substrate side) of the optical element can be easily taken out from the surface side of the optical element wafer. That is, the suppression reduces the ratio of light attenuated inside the optical element wafer after being emitted to the back side of the optical element, and the light extraction efficiency of the optical element wafer can be improved.

Further, in the method of manufacturing an optical element wafer according to the present invention, the inner wall surface of the V groove which is the side surface on the back side of the optical element wafer is polished, and the light extraction efficiency of the optical element wafer can be further improved.

11‧‧‧Light component wafer

11a‧‧‧ surface

11b‧‧‧Back

11c‧‧" field

13‧‧‧Light components

15‧‧‧Cutting tape

17‧‧‧ box

19‧‧‧Laser processing ditch

19a‧‧‧1st laser processing ditch

19b‧‧‧2nd laser processing ditch

21‧‧‧V ditch

23‧‧‧Protective strips

25‧‧‧ crack

27‧‧‧Guided modified layer

L1, L2‧‧‧ laser light

2‧‧‧ Laser processing equipment

4‧‧‧Laser processing unit

6‧‧‧ camera

8‧‧‧Cutting device

10‧‧‧Cutting unit

12‧‧‧ mandrel

14‧‧‧Cutting inserts

16‧‧‧ cutting device

18‧‧‧Cutting unit

20‧‧‧ mandrel

22‧‧‧Cutting inserts

24‧‧‧ Breaking device

26, 28‧‧‧ support blade

30‧‧‧ Pressing blade

32‧‧‧Sand blasting device

34‧‧‧Nozzles

36‧‧‧Abrased materials

38‧‧‧ Laser processing equipment

40‧‧‧Laser processing unit

Fig. 1 is a perspective view schematically showing a step of forming a laser processing groove.

[ Fig. 2] Fig. 2 (A) is a partial cross-sectional side view schematically showing a first laser processing groove forming step, and Fig. 2 (B) is a partial cross-sectional side view schematically showing a second laser processing groove forming step; Fig. 2(C) is a cross-sectional view showing a pair of laser processing grooves.

Fig. 3 is a partial cross-sectional side view schematically showing a step of forming a V groove.

[Fig. 4] is a schematic side view showing a part of the grinding step Figure.

Fig. 5 is a partial cross-sectional side view schematically showing one of the dividing steps.

Fig. 6 is a partial cross-sectional side view schematically showing one of polishing steps in a modification.

Fig. 7 is a partial cross-sectional side view schematically showing a step of forming a modified layer.

Embodiments of the present invention are described with reference to the accompanying drawings. The method of manufacturing an optical element wafer according to the present embodiment includes a laser processing groove forming step (see FIGS. 1 , 2 (A), 2 (B), and 2 (C)), and a V groove forming step. (See Figure 3), the grinding step (see Figure 4), and the dividing step (see Figure 5).

In the laser processing groove forming step, after irradiating the laser beam having an absorptive wavelength with respect to the optical element wafer, the laser processing groove is formed on the back side of the optical element wafer along one of the planned dividing lines. In the laser processing groove forming step, the pair of laser processing grooves are formed such that the shape of the cross section orthogonal to the planned dividing line is V-shaped.

In the V groove forming step, the optical element wafer existing between the pair of laser processing grooves is crushed and removed by a cutting blade to form a V-shaped V groove corresponding to the shape of the pair of laser processing grooves. In the polishing step, the inner wall surface of the V groove formed in the V groove forming step is polished.

In the dividing step, external force is applied to the optical element wafer in the V groove Cracks are generated between the predetermined dividing lines, and the optical element wafer is divided into a plurality of optical element wafers along the respective dividing lines. Hereinafter, a method of manufacturing the optical element wafer of the present embodiment will be described in detail.

First, a laser processing groove forming step in which the shape of the cross section is one of a V shape and the laser processing groove is formed on the back side of the optical element wafer is performed. Fig. 1 is a perspective view schematically showing a step of forming a laser processing groove. As shown in FIG. 1, the optical element wafer 11 of the present embodiment is constituted by, for example, a substrate made of a disk-shaped sapphire or SiC.

The surface (lower surface) 11a side of the optical element wafer 11 is divided into a plurality of fields by a plurality of predetermined dividing lines (cutting streets) which intersect each other, and is formed as a light emitting diode (LED) or a thunder in each field. The light element 13 of the diode (LD) is emitted. Each of the optical elements 13 includes a light-emitting layer formed by a method such as epitaxial growth.

On the surface 11a side of the optical element wafer 11, a dicing tape 15 having a larger diameter than the light-emitting element wafer 11 is attached. The outer peripheral portion of the dicing tape 15 is fixed to the annular frame 17. That is, the optical element wafer 11 is supported by the frame 17 via the dicing tape 15.

In the laser processing groove forming step according to the present embodiment, the laser beam is irradiated onto the back surface (upper surface) 11b side of the optical element wafer 11 to form a cross-sectional shape in the shape of a V-shaped laser processing groove. . This laser processing groove forming step is carried out, for example, by the laser processing apparatus 2 shown in Fig. 1 .

The laser processing apparatus 2 is provided with the optical element wafer 11 Clamp bed (not shown). The chuck bed is coupled to a rotary drive source such as a motor and rotates about a rotation axis parallel to the vertical direction (Z-axis direction). Further, a moving mechanism is provided below the chuck bed, and the chuck bed is moved in the horizontal direction (X-axis direction, Y-axis direction) by the moving mechanism.

The upper surface of the chuck bed is a holding surface that holds the surface 11a side of the optical element wafer 11 with the dicing tape 15 interposed therebetween. At the holding surface, the suction force of the suction source acts on the flow path formed inside the chuck bed, and the suction force of the light-receiving element wafer 11 is generated. A plurality of clamps (not shown) that hold the annular frame 17 are provided around the chuck bed.

Above the chuck bed, a laser processing unit 4 is arranged. At a position adjacent to the laser processing unit 4, a camera 6 for photographing the optical element wafer 11 is provided.

The laser processing unit 4 condenses the laser beam L1 pulsed by a laser oscillator (not shown) and then irradiates it onto the optical element wafer 11 on the chuck bed. The laser oscillator is configured to oscillate a laser beam L1 having a wavelength (absorptive wavelength) that is easily absorbed by the optical element wafer 11.

Further, a lens (not shown) that reflects the laser beam L1 is provided at a lower portion of the laser processing unit 4. With this lens, the laser beam L1 can be tilted with respect to the back surface 11b of the optical element wafer 11.

In the laser processing groove forming step of the present embodiment, first, the optical element wafer 11 and the dicing tape 15 are placed on the chuck. The bed is placed such that the surface 11a of the optical element wafer 11 faces the holding surface of the chuck bed with the dicing tape 15 interposed therebetween.

Next, the annular frame 17 is fixed by a clamp to apply a negative pressure of the suction source to the holding surface. As a result, the optical element wafer 11 is held on the chuck bed in a state where the back surface 11b side is exposed upward.

After the optical element wafer 11 is held by the chuck bed, a first laser processing groove forming step of forming the inclined first laser processing groove is performed. Fig. 2(A) is a partial cross-sectional side view schematically showing a first laser processing groove forming step.

In the first laser processing groove forming step, first, the chuck bed is moved and rotated, and the laser processing unit 4 is positioned to the processing start position (for example, the end portion of the planned dividing line to be processed).

Next, while irradiating the laser beam L1 from the laser processing unit 4 toward the back surface 11b of the optical element wafer 11, the chuck bed is moved in a direction parallel to the planned dividing line (Fig. 2(A) For the X-axis direction). Here, the laser light L1 is irradiated in a state of being inclined (obliquely) with respect to the back surface 11b of the optical element wafer 11.

More specifically, as shown in FIG. 2(A), the laser beam L1 is inclined from the vertical direction (the direction perpendicular to the back surface 11b) in the cross section orthogonal to the planned dividing line of the processing target. As a result, the back surface 11b side of the optical element wafer 11 is ablated along the planned dividing line of the processing target, and the first laser processing groove 19a inclined with respect to the back surface 11b can be formed.

Repeat the above procedure, for example, once along the entire score When the first predetermined laser processing groove 19a is formed by the planned cutting line, the first laser processing groove forming step is completed. Further, in the first laser processing groove forming step, the first laser processing groove 19a may be formed only for an arbitrarily selected dividing line.

After the first laser processing groove forming step is performed, the second laser processing groove forming step is performed to form a second laser processing groove that is inclined in a direction opposite to the first laser processing groove 19a. Fig. 2(B) is a partial cross-sectional side view schematically showing one step of forming the second laser processing groove.

The basic procedure of the second laser processing groove forming step is the same as the first laser processing groove forming step. However, in the second laser processing groove forming step, the laser beam is irradiated in a state in which the back surface 11b of the optical element wafer 11 is inclined in the opposite direction to the first laser processing groove forming step (obliquely). Light L1.

More specifically, as shown in FIG. 2(B), the laser beam L1 is tilted from the vertical direction (the direction perpendicular to the back surface 11b) to the first in the cross section orthogonal to the planned dividing line of the processing target. The laser processing groove forming step is in the opposite direction. As a result, the back surface 11b side of the optical element wafer 11 is ablated along the planned dividing line of the processing target, and the second laser processing can be formed in a direction opposite to the first laser processing groove 19a with respect to the back surface 11b. Groove 19b.

When the second laser processing groove 19b is formed along the predetermined dividing line along which all of the first laser processing grooves 19a are formed, the second laser processing groove forming step is completed.

2(C) is a cross-sectional view showing the first laser processing groove 19a and the second laser processing groove 19b (a pair of laser processing grooves 19) enlarged. As shown in FIG. 2(C), the first laser processing groove 19a and the second laser processing groove 19b are formed such that the shape of the cross section orthogonal to the planned dividing line is V-shaped.

The depths of the first laser processing groove 19a and the second laser processing groove 19b are arbitrary, and for example, it is preferably about half the thickness of the optical element wafer 11. Further, a part of the optical element wafer 11 remains in the field 11c surrounding the first laser processing groove 19a and the second laser processing groove 19b.

Further, in the present embodiment, the first laser processing groove 19a and the second laser processing groove 19b are formed such that the lower ends do not contact each other. However, the power or the spot diameter of the laser beam L1 may be adjusted to bring the lower ends of the first laser processing groove 19a and the second laser processing groove 19b into contact.

After the laser processing groove forming step is performed, the V groove forming step is performed, and the optical element wafer 11 of the field 11c existing between the pair of laser processing grooves 19 is crushed and removed by a cutting blade to form a corresponding A pair of V-shaped V-grooves of the shape of the laser processing groove 19. Fig. 3 is a partial cross-sectional side view schematically showing a step of forming a V groove.

The V groove forming step is carried out, for example, by the cutting device 8 shown in Fig. 3 . The cutting device 8 includes a chuck bed (not shown) that holds the optical element wafer 11. The chuck bed is coupled to a rotary drive source such as a motor and rotates about a rotation axis parallel to the vertical direction. Moreover, under the chuck bed, a machining feed mechanism is provided, and the chuck bed is processed by the chuck The feed mechanism moves in the machining feed direction.

The upper surface of the chuck bed is a holding surface that holds the surface 11a side of the optical element wafer 11 with the dicing tape 15 interposed therebetween. At the holding surface, the suction force of the suction source acts on the flow path formed inside the chuck bed, and the suction force of the light-receiving element wafer 11 is generated. A plurality of clamps (not shown) that hold the annular frame 17 are provided around the chuck bed.

A cutting unit 10 for cutting the optical element wafer 11 is disposed above the chuck bed. The cutting unit 10 includes a mandrel 12 supported to be rotatable, and a cutting insert 14 attached to one end side of the mandrel 12. A rotary drive source (not shown) such as a motor is coupled to the other end side of the mandrel 12, and is attached to the cutting insert 14 of the mandrel 12 to rotate by the rotational force of the rotary drive source.

The cutting insert 14 is configured to be suitable for processing the optical element wafer 11. For example, when the main component of the optical element wafer 11 is sapphire, a metal sintered blade of #400 to #1000 can be used as the cutting insert 14.

The cutting unit 10 is supported by a lifting mechanism (not shown) and moved (lifted) in the vertical direction. Further, an indexing feed mechanism (not shown) is provided below the lifting mechanism; the cutting unit 10 is moved in the indexing feed direction by the indexing feed mechanism.

In the V groove forming step, first, the optical element wafer 11 and the dicing tape 15 are placed on the chuck bed so that the surface 11a of the optical element wafer 11 and the chuck bed are interposed by the dicing tape 15 interposed therebetween. Stationary surface Opposite.

Next, the annular frame 17 is fixed by a clamp to apply a negative pressure of the suction source to the holding surface. As a result, the optical element wafer 11 is held on the chuck bed in a state where the back surface 11b side is exposed upward.

Next, the chuck bed is moved and rotated, and the cutting insert 14 is positioned to the machining start position (for example, the end portion of the field 11c to be processed). Then, the lower end (end) of the rotating cutting insert 14 is cut into the field 11c to be processed, and the chuck bed is moved (machining feed) in the direction corresponding to the field 11c to be processed (in FIG. 3 Direction D1).

Thereby, the optical element wafer 11 existing in the field 11c between the pair of laser processing grooves 19 is broken and removed by the cutting insert 14, and a V shape corresponding to the shape of the pair of laser processing grooves 19 can be formed. The shape of the V groove 21.

The V groove 21 is formed to have a depth corresponding to the pair of laser processing grooves 19. For example, when the depth of the pair of laser processing grooves 19 is about half the thickness of the optical element wafer 11, the depth of the V groove 21 is also about half of the thickness of the optical element wafer 11.

Further, in the V groove forming step, the cutting insert 14 is rotated from the inside of the optical element wafer 11 toward the back surface 11b at the processing point where the optical element wafer 11 is in contact with the cutting insert 14 (the inverse milling method). It is better. Thereby, the optical element wafer 11 existing in the field 11c can be surely removed, and the V groove 21 can be formed. Repeating the above procedure, once the V-groove is formed along a predetermined dividing line forming a pair of laser processing grooves 19 In the case of 21, the V groove forming step is ended.

After the V groove forming step is performed, a polishing step of polishing the inner wall surface of the V groove is performed. Fig. 4 is a partial cross-sectional side view schematically showing one step of polishing. The polishing step is carried out, for example, by the cutting device 16 shown in Fig. 4 . The basic configuration of the cutting device 16 is the same as that of the cutting device 8 used in the V groove forming step.

That is, the cutting device 16 includes a chuck bed (not shown) that holds the optical element wafer 11. A cutting unit 18 for cutting the optical element wafer 11 is disposed above the chuck bed. The cutting unit 18 includes: a mandrel 20 supported to be rotatable; and a cutting insert 22 attached to one end side of the mandrel 20.

The cutting insert 22 is configured such that the optical element wafer 11 can be appropriately polished. For example, when the main component of the optical element wafer 11 is sapphire, a metal sintered blade of #800 to #3000, a vitrified bond blade, an electroformed blade, or the like can be used as the cutting insert 22.

Further, the end of the cutting insert 22 is formed in a V shape corresponding to the V groove as shown in FIG. By cutting the cutting insert 22 slightly into the V groove 21 and moving the chuck bed (machining feed) in a direction corresponding to the V groove 21 to be processed (direction D2 in Fig. 4), the cutting V can be cut. The groove 21 grinds the inner wall surface.

Further, in the present embodiment, the cutting insert 22 is rotated in the direction from the back surface 11b of the optical element wafer 11 toward the inside (the milling method); however, the cutting insert 22 may be turned from the inside toward the back. The direction of the surface 11b is rotated (up-milling method). In response to the above procedure, once the inner wall surfaces of all the V grooves 21 are polished, the polishing step is terminated.

After the polishing step is performed, a division step is performed to apply an external force to the optical element wafer 11 to divide into a plurality of optical element wafers. Fig. 5 is a partial cross-sectional side view schematically showing one of the dividing steps.

The dividing step is carried out, for example, by the breaking device 24 shown in Fig. 5 . The breaking device 24 includes a pair of support blades 26 and 28 that support the optical element wafer 11 and a pressing blade 30 that is disposed above the support blades 26 and 28. The pressing blade 30 is positioned between the support blade 26 and the support blade 28, and is moved (lifted) in the vertical direction by a pressing mechanism (not shown).

In the singulation process, first, the optical element wafer 11 is placed on the support blades 26, 28 with the surface 11a side positioned above. Further, the protective tape 23 is attached to the back surface 11b side of the optical element wafer 11 in advance.

Next, the optical element wafer 11 is moved with respect to the support blades 26 and 28, and the V groove 21 is provided between the support blade 26 and the support blade 28. That is, as shown in FIG. 5, the V groove 21 is moved right below the pressing blade 30.

Thereafter, the pressing blade 30 is lowered, and the optical element wafer 11 is pressed by the pressing blade 30 from the side of the back surface 11b. The optical element wafer 11 supports both sides of the V groove 21 from below by the support blades 26 and 28. For this reason, when the optical element wafer 11 is pressed by the pressing blade 30, a bending stress in the downward direction is applied in the vicinity of the V groove 21, and a crack is generated between the planned dividing line of the surface 11a and the V groove 21 on the side of the back surface 11b. .

In this manner, the bending element can be generated by applying the bending stress in the vicinity of the V groove 21 formed along the planned dividing line, and the optical element wafer 11 can be divided. When the optical element wafer 11 is divided along the predetermined dividing line forming the V-groove 21, and a plurality of optical element wafers corresponding to the respective optical elements 13 are formed, the dividing step is ended.

As described above, in the method of manufacturing an optical element wafer according to the present embodiment, the V-groove 21 having a V-shaped cross section is formed on the back surface 11b side of the optical element wafer 11 along the planned dividing line, thereby imparting an external force. When the optical element wafer 11 is divided into individual optical element wafers, the side surface on the back side of the completed optical element wafer (the inner wall surface of the V groove 21) is formed on the light-emitting layer formed on the surface side. The optical element 13 is inclined.

As a result, for example, in the optical element wafer from which the light is taken out from the surface side, light emitted to the back side (substrate side) of the optical element 13 is easily taken out from the surface side of the optical element wafer. In other words, the ratio of light attenuated inside the optical element wafer after being emitted to the back side (substrate side) of the optical element 13 is suppressed, and the light extraction efficiency of the optical element wafer can be improved.

Further, in the method of manufacturing an optical element wafer according to the present invention, the inner wall surface of the V groove 21 which is the side surface on the back side of the optical element wafer is polished, and the light extraction efficiency of the optical element wafer can be further improved.

Further, the present invention is not limited to the description of the above embodiments, and can be implemented in various modifications. For example, in the above embodiment, the V groove 21 is polished by the cutting insert 22, but a method such as sand blasting (bead hitting) may be applied to the polishing step of the present invention. Figure 6 is a schematic representation of A partial cross-sectional side view of one of the grinding steps of the modified example.

The polishing step of the modification is carried out, for example, by the sand blasting device 32 shown in Fig. 6 . As shown in FIG. 6, the blasting apparatus 32 is provided with the nozzle 34. The inner wall surface of the V groove 21 can be polished in the same manner as the polishing step of the above-described embodiment so that the polishing material 36 is discharged from the nozzle 34.

Further, a guide reforming layer for guiding the crack 25 may be formed before the pair of laser processing grooves 19 are formed to the optical element wafer 11. Fig. 7 is a partial cross-sectional side view schematically showing a step of forming a guiding reforming layer.

The guiding reforming layer forming step is carried out, for example, by the laser processing device 38 shown in FIG. The basic configuration of the laser processing apparatus 38 is the same as that of the laser processing apparatus 2 used in the laser processing groove forming step.

In other words, the laser processing unit 38 includes a laser processing unit 40 that condenses the laser beam L2 pulsed by a laser oscillator (not shown) and then irradiates the optical element on the chuck bed. Wafer 11. However, the laser oscillator of the laser processing apparatus 38 constitutes a laser beam L2 that can oscillate a wavelength (wavelength having transparency) that is hard to be absorbed by the optical element wafer 11.

In the step of forming the reforming layer, first, the chuck bed holding the optical element wafer 11 is moved and rotated, and the laser processing unit 40 is positioned to the processing start position (for example, a planned dividing line to be processed) End).

Next, the laser beam L2 is irradiated from the laser processing unit 40 toward the back surface 11b of the optical element wafer 11, and the chuck bed is moved in a direction parallel to the planned dividing line of the processing target. Here, the laser beam L2 is condensed between the planned dividing line of the surface 11a and the field which becomes the bottom of the V-groove 21.

Thereby, the guide reforming layer 27 caused by multiphoton absorption can be formed between the division planned line and the region which becomes the bottom of the V groove 21 along the planned dividing line of the object to be processed. Once the guide reforming layer 27 is formed along the predetermined entire predetermined dividing line forming the V-groove 21, the guiding reforming layer forming step is ended.

In the case where the above-described guide reforming layer 27 is formed, the crack 25 can be appropriately guided in the dividing step, and the division failure of the optical element wafer can be prevented. Other configurations, methods, and the like of the above-described embodiments may be appropriately modified and implemented without departing from the scope of the invention.

2‧‧‧ Laser processing equipment

4‧‧‧Laser processing unit

6‧‧‧ camera

11‧‧‧Light component wafer

11a‧‧‧ surface

11b‧‧‧Back

13‧‧‧Light components

15‧‧‧Cutting tape

17‧‧‧ box

19‧‧‧Laser processing ditch

L1‧‧‧Laser light

Claims (4)

A method of manufacturing an optical element wafer, wherein an optical element wafer in which an optical element including a light-emitting layer is included in each of a plurality of predetermined dividing lines arranged on a surface and intersecting each other is formed along The dividing line is divided to produce a plurality of optical element wafers, and the laser processing groove forming step includes obliquely irradiating the back surface of the optical element wafer with an absorptive wavelength with respect to the optical element wafer. The laser beam has a shape of a cross section orthogonal to the predetermined dividing line in a V shape, and the laser processing groove is formed on the back side of the optical element wafer along the dividing line; the V groove forming step is performed After the laser processing groove forming step, the optical element wafer existing in the field between the pair of laser processing grooves is crushed and removed by the cutting insert to form a shape corresponding to the shape of the pair of laser processing grooves. a V-shaped V-groove; a polishing step of polishing the inner wall surface of the V-groove after performing the V-groove forming step; and a dividing step of applying the polishing step to the optical element wafer Generating a crack between the division lines in the V-grooves and, the optical device wafer is divided along the respective division lines into a light receiving element of a wafer. The method of manufacturing an optical element wafer according to claim 1, wherein in the V groove forming step, the back milling method is performed at a processing point where the optical element wafer is in contact with the cutting blade, and is inside the optical element wafer. The cutting insert is rotated in the direction toward the back. The method of manufacturing the optical element wafer of claim 1 or claim 2, wherein in the polishing step, the V-groove is cut by a cutting blade having a shape of a V-shaped end corresponding to the V-groove to grind the V The inner wall of the trench. The method of manufacturing the optical element chip of claim 1 or claim 2, further comprising a step of forming a reforming layer before the step of forming the laser processing trench, which has a step relative to the optical element wafer The laser light of the transparent wavelength is irradiated onto the optical element wafer, and in the dividing step, a guiding reforming layer for guiding the crack is formed along the dividing line.