Method of manufacturing the element

Abstract

The present invention provides a method for manufacturing an element that can reduce the expansion of chipping in the plate material. [Solution] The method for manufacturing the element comprises the steps of: preparing a plate material having a first surface; scanning a laser beam along a first direction parallel to the first surface to form a first modified portion inside the plate material along the first direction; scanning a laser beam along the first direction to form a second modified portion in the plate material at a position away from the first modified portion in a plan view along the first direction; and framing the plate material, wherein the framing step includes removing a first portion between the first modified portion and the second modified portion in the plate material in a plan view.

Description

Technical Field

[0001] This disclosure relates to a method for manufacturing an element.

Background Art

[0002] In manufacturing an element such as a light-emitting device, a plate material such as a substrate on which a semiconductor layer or the like is formed may be divided into a plurality of pieces. In dividing the plate material, for example, machining using a dicing blade is performed. Further, Patent Document 1 discloses a laser dicing method for a workpiece substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In dividing a plate material by machining, chipping may occur in the plate material starting from a location where the dicing blade contacts in the initial stage of machining. In the conventional method, the chipping may expand and desired characteristics may not be obtained for the element.

[0005] An object of this disclosure is to provide a method for manufacturing an element capable of reducing the expansion of chipping of a plate material.

Means for Solving the Problems

[0006] According to one aspect of the disclosed technology, a method for manufacturing an element comprises the steps of: preparing a plate material having a first surface; scanning a laser beam along a first direction parallel to the first surface to form a first modified portion inside the plate material along the first direction; scanning a laser beam along the first direction to form a second modified portion in the plate material at a position away from the first modified portion in a plan view along the first direction; and framing the plate material, wherein the framing step includes removing a first portion between the first modified portion and the second modified portion in the plate material in a plan view. [Effects of the Invention]

[0007] According to this disclosure, the expansion of chipping in the plate material can be reduced. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-sectional view illustrating a method for manufacturing an element according to the first embodiment. [Figure 2] This is a cross-sectional view illustrating a method for manufacturing an element according to the first embodiment. [Figure 3] This is a cross-sectional view illustrating a method for manufacturing an element according to the first embodiment. [Figure 4] This is a cross-sectional view illustrating a method for manufacturing an element according to the first embodiment. [Figure 5] This is a cross-sectional view illustrating a method for manufacturing an element according to the first embodiment. [Figure 6] This is a cross-sectional view illustrating a method for manufacturing an element according to the first embodiment. [Figure 7] This is a plan view illustrating a method for manufacturing an element according to the first embodiment. [Figure 8] This is a plan view illustrating a method for manufacturing an element according to the first embodiment. [Figure 9] This is a cross-sectional view illustrating a method for manufacturing an element according to the second embodiment. [Figure 10] This is a cross-sectional view illustrating a method for manufacturing an element according to the second embodiment. [Figure 11]It is a cross-sectional view illustrating a method for manufacturing an element according to the second embodiment. [Figure 12] It is a cross-sectional view illustrating a method for manufacturing an element according to the second embodiment. [Figure 13] It is a cross-sectional view illustrating a method for manufacturing an element according to the second embodiment. [Figure 14] It is a cross-sectional view illustrating a method for manufacturing an element according to the second embodiment. [Figure 15] It is a plan view illustrating a method for manufacturing an element according to the second embodiment. [Figure 16] It is a plan view illustrating a method for manufacturing an element according to the second embodiment. [Figure 17] It is a view showing an observation result around a groove formed under the first condition. [Figure 18] It is a view showing an observation result around a groove formed under the second condition.

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments for implementing the present disclosure will be described while referring to the drawings. The following description is for embodying the technical idea of the present disclosure, and unless there is a specific description, the present disclosure is not limited to the following description.

[0010] In each drawing, members having the same function may be denoted by the same reference numerals. For the sake of explanation of the gist or ease of understanding, they may be shown separately in embodiments for convenience, but partial substitution or combination of configurations shown in different embodiments or examples is possible. In the embodiments shown later, mainly the matters different from the previously shown embodiments will be described, and duplicate explanations for matters common to the previously shown embodiments may be omitted. The sizes and positional relationships of the members shown in each drawing may be exaggerated for clarity of explanation. In order to avoid excessive complexity of the drawings, illustration of some elements may be omitted, or an end view showing only the cut surface as a cross-sectional view may be used.

[0011] (First Embodiment) A first embodiment will be described. The first embodiment relates to a method for manufacturing an element. Figures 1 to 6 are cross-sectional views illustrating the method for manufacturing an element according to the first embodiment. Figures 7 to 8 are plan views illustrating the method for manufacturing an element according to the first embodiment.

[0012] As shown in Figures 1 to 8, the method for manufacturing the element according to the first embodiment includes the steps of: preparing a wavelength conversion member 30 having a first surface 30a; scanning a laser beam L1 along a first direction parallel to the first surface 30a to form a first modified portion 121 inside the wavelength conversion member 30 along the first direction; scanning a laser beam L2 along the first direction to form a second modified portion 122 inside the wavelength conversion member 30 at a position away from the first modified portion 121 in a plan view; and framing the wavelength conversion member 30, wherein the framing step of the wavelength conversion member 30 includes removing a first portion 31 between the first modified portion 121 and the second modified portion 122 in the wavelength conversion member 30 in a plan view. The step of separating the wavelength conversion member 30 into individual pieces may further include the step of forming a first groove 36 in the wavelength conversion member 30 by removing the first portion 31, and the step of cutting the wavelength conversion member 30 at a position that overlaps with the first groove 36 in a plan view. Furthermore, the method for manufacturing the element according to the first embodiment includes the steps of: scanning a laser beam along a second direction intersecting a first direction to form a third modified portion 123 along the second direction inside the wavelength conversion member 30; scanning a laser beam along the second direction to form a fourth modified portion 124 along the second direction at a position away from the third modified portion 123 inside the wavelength conversion member 30 in a plan view; and removing a second portion 32 between the third modified portion 123 and the fourth modified portion 124 in the wavelength conversion member 30 in a plan view, wherein the step of removing the second portion 32 may include the steps of forming a second groove 37 in the wavelength conversion member 30 by removing the wavelength conversion member 30; and cutting the wavelength conversion member 30 at a position overlapping with the second groove 37 in a plan view.

[0013] <Steps for preparing the wavelength conversion member 30> First, as shown in Figure 1, a wavelength conversion member 30 is prepared as a plate material. The wavelength conversion member 30 has a first surface 30a and a second surface 30b located on the opposite side of the first surface 30a.

[0014] A sintered phosphor can be used for the wavelength conversion member 30. A sintered phosphor is a member obtained by sintering a phosphor together with ceramics such as aluminum oxide, aluminum nitride, silicon nitride, silicon carbide, zirconium oxide, and titanium oxide, and does not contain resin. By using a sintered phosphor for the wavelength conversion member 30, the heat dissipation of the phosphor is improved compared to a member in which the phosphor is contained in a resin (binder), thus reducing the decrease in wavelength conversion efficiency. The phosphor is a yttrium-aluminum-garnet phosphor (for example, Y3(Al,Ga)5O 12 Ce), lutetium-aluminum-garnet phosphors (e.g., Lu3(Al,Ga)5O 12 Ce), terbium aluminum garnet phosphors (e.g., Tb3(Al,Ga)5O 12 :Ce), β-sialon phosphors (e.g., (Si,Al)3(O,N)4:Eu), α-sialon phosphors (e.g., Ca(Si,Al) 12 (O,N) 16 Nitride-based phosphors such as (Eu), CASN-based phosphors (e.g., CaAlSiN3:Eu), or SCASN-based phosphors (e.g., (Sr,Ca)AlSiN3:Eu), fluoride-based phosphors such as KSF-based phosphors (e.g., K2SiF6:Mn), KSAF-based phosphors (e.g., K2(Si,Al)F6:Mn), or MGF-based phosphors (e.g., 3.5MgO·0.5MgF2·GeO2:Mn), perovskite-structured phosphors (e.g., CsPb(F,Cl,Br,I)3), or quantum dot phosphors (e.g., CdSe, InP, AgInS2, or AgInSe2) can be used. The thickness of the wavelength conversion member 30 is, for example, 100 μm or more and 400 μm or less, preferably 120 μm or more and 300 μm or less, and more preferably 130 μm or more and 260 μm or less.

[0015] Next, a structure 111 is prepared, which includes a wavelength conversion member 30, a light-transmitting layer 20, a light-emitting part 60, a conductive layer 55, a first insulating film 51, a second insulating film 52, a p-side electrode 71, an n-side electrode 72, a p-side external connection electrode 81, and an n-side external connection electrode 82.

[0016] The light-transmitting layer 20 and the light-emitting part 60 are arranged on the second surface 30b side. Multiple light-transmitting layers 20 are arranged on the wavelength conversion member 30, and the light-emitting part 60 is arranged on each light-transmitting layer 20.

[0017] The material for the light-transmitting layer 20 can be, for example, silicon oxide or silicon nitride.

[0018] The light-emitting section 60 has a semiconductor layer 10, which has an n-side semiconductor layer 11, a p-side semiconductor layer 13, and an active layer 12 located between the n-side semiconductor layer 11 and the p-side semiconductor layer 13. The n-side semiconductor layer 11 is arranged on the light-transmitting layer 20, the active layer 12 is arranged on the n-side semiconductor layer 11, and the p-side semiconductor layer 13 is arranged on the active layer 12. The active layer 12 is a light-emitting layer that emits light, for example, light with an emission peak wavelength of 210 nm to 580 nm. The active layer 12 can have a multiple quantum well (MQW) structure, for example, which includes a plurality of barrier layers and a plurality of well layers. The n-side semiconductor layer 11 has a semiconductor layer containing n-type impurities. The p-side semiconductor layer 13 has a semiconductor layer containing p-type impurities.

[0019] The semiconductor layer 10 has a surface 10a that is in contact with the light-transmitting layer 20. Light emitted from the active layer 12 is mainly extracted from the surface 10a to the outside of the semiconductor layer 10. The surface 10a may be roughened. Roughening the surface 10a can improve the efficiency of light extraction from the surface 10a. When the surface 10a is roughened, its arithmetic mean roughness Ra is, for example, 100 nm to 250 nm.

[0020] The n-side semiconductor layer 11 has a first n-side exposed surface 11a and a second n-side exposed surface 11b. The first n-side exposed surface 11a and the second n-side exposed surface 11b are located on the opposite side of surface 10a and are exposed from the active layer 12 and the p-side semiconductor layer 13.

[0021] The semiconductor layer 10 is made of a nitride semiconductor. In this specification, "nitride semiconductor" means, for example, In x Al y Ga 1-x-y This term includes semiconductors with all compositions obtained by varying the composition ratios x and y within the respective ranges in the chemical formula N(0≦x≦1,0≦y≦1,x+y≦1). Furthermore, "nitride semiconductors" also include those that further contain group V elements other than N (nitrogen) in the above chemical formula, and those that further contain various elements added to control various physical properties such as conductivity.

[0022] There are gaps 61 between adjacent laminates of light-transmitting layers 20 and light-emitting parts 60, and these gaps 61 are formed, for example, in a grid pattern in a plan view. The light-emitting parts 60 are arranged in a matrix in a plan view (see Figures 7 and 8). The gaps 61 extend in a direction that penetrates the plane of the paper in Figure 1.

[0023] The conductive layer 55 is placed on the p-side semiconductor layer 13 and is electrically connected to the p-side semiconductor layer 13. The conductive layer 55 has the function of diffusing the current supplied from the p-side electrode (described later) in the planar direction of the p-side semiconductor layer 13.

[0024] Furthermore, the conductive layer 55 can have high reflectivity to light emitted by the active layer 12. High reflectivity of the conductive layer 55 means that it has a reflectance of 50% or more, preferably 60% or more, with respect to the emission peak wavelength of the light emitted by the active layer 12. For example, silver or aluminum can be used as the material for the conductive layer 55. Furthermore, the conductive layer 55 can have transmittance to light emitted by the active layer 12. High reflectivity of the conductive layer 55 means that it has a light transmittance of 50% or more, preferably 60% or more, with respect to the emission peak wavelength of the light emitted by the active layer 12. For example, indium tin oxide (ITO), indium oxide (In2O3), zinc oxide (ZnO), etc., can be used as the material for the conductive layer 55.

[0025] The first insulating film 51 covers the upper surface of the p-side semiconductor layer 13 and the conductive layer 55. By covering the conductive layer 55 with the first insulating film 51, the influence of moisture and other factors on the conductive layer 55 is reduced, and the occurrence of migration of the conductive layer 55 can be reduced. For example, a silicon oxide film or a silicon nitride film can be used as the first insulating film 51.

[0026] The second insulating film 52 covers the first insulating film 51. The second insulating film 52 also covers a portion of the first n-side exposed surface 11a and the second n-side exposed surface 11b. Furthermore, the second insulating film 52 covers the side surface of the light-emitting portion 60 that is continuous with the first n-side exposed surface 11a and the upper surface of the p-side semiconductor layer 13, and the side surface of the light-emitting portion 60 that is continuous with the second n-side exposed surface 11b and the upper surface of the p-side semiconductor layer 13.

[0027] The p-side electrode 71 and the n-side electrode 72 are arranged on the second insulating film 52. The p-side electrode 71 is in contact with the upper surface of the conductive layer 55 at an opening formed in the second insulating film 52 and an opening formed in the first insulating film 51. The p-side electrode 71 is electrically connected to the p-side semiconductor layer 13 via the conductive layer 55. The n-side electrode 72 is in contact with the first n-side exposed surface 11a and is electrically connected to the n-side semiconductor layer 11.

[0028] For example, metallic materials such as Ag, Ni, Ti, Pt, Al, Ru, Rh, Au, or alloys thereof can be used as the material for the p-side electrode 71 and the n-side electrode 72. The p-side electrode 71 and the n-side electrode 72 may be a single layer of the above metallic material or a laminated structure having multiple metallic layers.

[0029] The p-side external connection electrode 81 is positioned on the p-side electrode 71 and electrically connected to the p-side electrode 71. The n-side external connection electrode 82 is positioned on the n-side electrode 72 and electrically connected to the n-side electrode 72. The thickness of the p-side external connection electrode 81 and the thickness of the n-side external connection electrode 82 are greater than the thickness of the p-side electrode 71 and the thickness of the n-side electrode 72.

[0030] For the p-side external connection electrode 81 and the n-side external connection electrode 82, for example, metallic materials such as Ag, Ni, Ti, Pt, Al, Ru, Rh, Au, or alloys thereof can be used. The p-side external connection electrode 81 and the n-side external connection electrode 82 may be a single layer of the above metallic material or a laminated structure having multiple metallic layers.

[0031] <Steps for forming the first and second modified sections, and steps for forming the third and fourth modified sections> After the preparation of the structure 111, support members 40 are attached to the p-side external connection electrode 81 and the n-side external connection electrode 82, as shown in Figure 2. For example, an ultraviolet-curable resin sheet can be used as the support member 40. The support member 40 has a surface 40a on the side facing the structure 111 and a surface 40b on the opposite side of surface 40a. The support member 40 supports the multiple light-emitting units 60. The multiple light-emitting units 60 are positioned between the wavelength conversion member 30 and the support member 40.

[0032] Next, as shown in Figure 3, laser light L1 and laser light L2 are irradiated into the wavelength conversion member 30. Figures 3 and 4 show an enlarged view of the region R1 indicated by the dashed line in Figure 2. Laser light L1 and laser light L2 are, for example, pulsed laser light. In this case, the pulse width is, for example, 100 fs or more and 10 ps or less, preferably 100 fs or more and less than 3 ps. The peak wavelengths of laser light L1 and laser light L2 are, for example, 350 nm or more and 1100 nm or less, preferably 700 nm or more and less than 1100 nm. The spot diameter of laser light L1 and laser light L2, i.e., the minimum beam diameter, is, for example, 1 μm or more and 10 μm or less, preferably 1 μm or more and less than 5 μm. For example, laser light L1 and laser light L2 are irradiated into the wavelength conversion member 30 from the first surface 30a side opposite to the second surface 30b side on which the light-transmitting layer 20 and light-emitting part 60 are arranged. In this embodiment, as shown in Figures 3 and 7, in a plan view perpendicular to the first surface 30a, the laser beam L1 is scanned over the portion overlapping with one of the light-emitting units 60 adjacent to the gap 61, and the laser beam L2 is scanned over the portion overlapping with the other light-emitting unit 60. The laser beams L1 and L2 may also be scanned so as to overlap only the gap 61 in a plan view perpendicular to the first surface 30a. In Figure 3, the laser beams L1 and L2 are scanned in a first direction that penetrates the plane of the paper.

[0033] The laser beam L1 is focused at a specific depth inside the wavelength conversion member 30, and the energy of the laser beam L1 is concentrated at that location, forming a first modified portion 121 inside the wavelength conversion member 30. Similarly, the laser beam L2 is focused at a specific depth inside the wavelength conversion member 30, and the energy of the laser beam L2 is concentrated at that location, forming a second modified portion 122 in a plan view, at a location away from the first modified portion 121 inside the wavelength conversion member 30. As the laser beams L1 and L2 are scanned in a first direction, the first modified portion 121 and the second modified portion 122 are formed along the first direction, as shown in Figure 7. The first modified portion 121 and the second modified portion 122 are more brittle than the parts where neither the laser beam L1 nor the laser beam L2 is focused. As shown in Figure 3, the first modified portion 121 formed by irradiation with the laser beam L1 generates stress, and this stress causes a first crack 131 to form inside the wavelength conversion member 30. The second modified portion 122 formed by irradiation with laser light L2 generates stress, and this stress causes a second crack 132 to form inside the wavelength conversion member 30. The first crack 131 extends from the first modified portion 121 in the thickness direction of the wavelength conversion member 30, and the second crack 132 extends from the second modified portion 122 in the thickness direction of the wavelength conversion member 30.

[0034] Next, similar to the irradiation of laser beams L1 and L2, laser beams are irradiated into the inside of the wavelength conversion member 30 along a second direction intersecting the first direction, and as shown in Figure 7, a third modified portion 123 is formed inside the wavelength conversion member 30 along the second direction, and a fourth modified portion 124 is formed inside the wavelength conversion member 30 along the second direction at a position away from the third modified portion 123 in a plan view.

[0035] Note that in Figures 7 and 8, only the wavelength conversion member 30 and the light-emitting part 60 are shown, and other members are omitted. Also, in Figures 7 and 8, the first modification part 121, the second modification part 122, the third modification part 123 and the fourth modification part 124 are shown as points, but adjacent first modification parts 121 may be connected to form the first modification part 121 in a linear shape, adjacent second modification parts 122 may be connected to form the second modification part 122 in a linear shape, adjacent third modification parts 123 may be connected to form the third modification part 123 in a linear shape, and adjacent fourth modification parts 124 may be connected to form the fourth modification part 124 in a linear shape.

[0036] The laser beams L1 and L2 may be irradiated into the interior of the wavelength conversion member 30 from the second surface 30b side. However, by irradiating the laser beams L1 and L2 from the first surface 30a side, the light-emitting section 60 is less likely to be damaged by the laser beams L1 and L2 compared to when the laser beams L1 and L2 are irradiated from the second surface 30b side. When the laser beams L1 and L2 are irradiated from the second surface 30b side, there is a possibility that a portion of the laser beams L1 and L2 that are focused toward the interior of the wavelength conversion member 30 may irradiate the light-emitting section 60, potentially causing damage to the light-emitting section 60. The same applies to the laser beams used to form the third modified section 123 and the fourth modified section 124.

[0037] <Process for separating the wavelength conversion member 30 into individual pieces> [Steps to remove the first part (step to form the first groove), step to remove the second part (step to form the second groove)] After the steps of forming the first modified portion 121 and the second modified portion 122, and the steps of forming the third modified portion 123 and the fourth modified portion 124, as shown in Figures 4 and 8, the first portion 31 between the first modified portion 121 and the second modified portion 122 of the wavelength conversion member 30 is removed in a plan view. For example, the first groove 36 is formed by removing a part of the wavelength conversion member 30 between the first modified portion 121 and the second modified portion 122 from the first surface 30a side. The first groove 36 can be formed by machining (cutting) the wavelength conversion member 30 using a cutting member 320 such as a dicing blade. For example, the first groove 36 is formed so that a part of it overlaps with the light-emitting portion 60 in a plan view. The first groove 36 may also be formed so that it does not overlap with the light-emitting portion 60 in a plan view. In Figure 4, the first groove 36 extends in a first direction that penetrates the plane of the paper. The first groove 36 is defined by a bottom surface 36a and a side surface 36b that connects the first surface 30a and the bottom surface 36a.

[0038] Next, similar to the removal of the first portion 31, the second portion 32 between the third modified portion 123 and the fourth modified portion 124 of the wavelength conversion member 30 is removed in a plan view. For example, similar to the formation of the first groove 36, the second groove 37 is formed by removing a portion of the wavelength conversion member 30 between the third modified portion 123 and the fourth modified portion 124 from the first surface 30a side. The second groove 37 can also be formed by machining (cutting) the wavelength conversion member 30. In Figure 8, the first groove 36 and the second groove 37 are shown with dashed lines.

[0039] [Step of cutting the wavelength conversion member 30] After the steps of forming the first groove 36 and the second groove 37, the wavelength conversion member 30 is fractured starting from the first groove 36. For example, as shown in Figure 5, the wavelength conversion member 30 can be fractured by pressing the support member 40 with the pressing member 310. For example, in a plan view, a pressing force is applied to the support member 40 from the surface 40b side by the pressing member 310 at a position that overlaps with the first groove 36. When the support member 40 receives a pressing force from the surface 40b side, a large tensile stress parallel to the first surface 30a acts on the wavelength conversion member 30. As a result, the wavelength conversion member 30 begins to crack from the first surface 30a side, starting from the first groove 36. In this way, the wavelength conversion member 30 can be fractured at a position that overlaps with the first groove 36 in a plan view. Furthermore, by applying a pressing force from the pressing member 310 to the support member 40 from the surface 40b side at a position that overlaps with the second groove 37 in a plan view, the wavelength conversion member 30 can be cut at a position that overlaps with the second groove 37 in a plan view.

[0040] After the step of cutting the wavelength conversion member 30, the light-emitting part 60 is separated from the support member 40 as shown in Figure 6. Specifically, the support member 40 is peeled off from the p-side external connection electrode 81 and the n-side external connection electrode 82. If an ultraviolet-curable resin sheet is used as the support member 40, the support member 40 can be irradiated with ultraviolet light to reduce its adhesive strength, after which the light-emitting part 60 can be separated from the support member 40. As a result, a light-emitting device 1, which is an example of a plurality of elements including the light-emitting part 60, is obtained from the structure 111.

[0041] In the light-emitting device 1 manufactured in this manner, the light emitted from the light-emitting section 60 enters the wavelength conversion member 30 through the first surface 30a and is emitted from the first surface 30a, which is the light extraction surface.

[0042] When the wavelength conversion member 30 is separated into individual pieces, chipping is likely to occur. In particular, when the wavelength conversion member 30 is separated into individual pieces using a cutting member 320, the wavelength conversion member 30 is likely to chip starting from the point where the cutting member 320 makes contact. If a large chip occurs in the wavelength conversion member 30, the light emission characteristics of the light-emitting device 1 may change. In contrast, in the first embodiment, the first modified portion 121 and the second modified portion 122 are formed before the removal of the first portion 31, and the first portion 31 is the portion between the first modified portion 121 and the second modified portion 122. Therefore, even if chipping occurs in the wavelength conversion member 30, the expansion of the chip is stopped at the first modified portion 121, the first crack 131, the second modified portion, and the second crack 132, and the expansion of the chip in the wavelength conversion member 30 can be reduced. Similarly, when removing the second portion 32, the expansion of the chip in the wavelength conversion member 30 can also be reduced. Thus, stable light emission characteristics can be obtained for the light-emitting device 1.

[0043] When the first portion 31 is separated from the first modified portion 121 and the second modified portion 122, and when the second portion 32 is separated from the third modified portion 123 and the fourth modified portion 124, it is particularly easy to prevent the expansion of the chipping of the wavelength conversion member 30. However, the first portion 31 does not need to be separated from the first modified portion 121 and the second modified portion 122; even if the first portion 31 overlaps with the first modified portion 121 and the second modified portion 122, the expansion of the chipping can be made less likely. Similarly, the second portion 32 does not need to be separated from the third modified portion 123 and the fourth modified portion 124; even if the second portion 32 overlaps with the third modified portion 123 and the fourth modified portion 124, the expansion of the chipping can be made less likely.

[0044] It is preferable that the first modified portion 121 and the second modified portion 122 are formed closer to the first surface 30a than to the second surface 30b. Similarly, it is preferable that the third modified portion 123 and the fourth modified portion 124 are formed closer to the first surface 30a than to the second surface 30b. Chips in the wavelength conversion member 30 are likely to occur in the initial stages when removing the wavelength conversion member 30 from the first surface 30a side. Therefore, forming the first modified portion 121 and the second modified portion 122 closer to the first surface 30a makes it easier to prevent the chipping from expanding when removing the first portion 31. Similarly, forming the third modified portion 123 and the fourth modified portion 124 closer to the first surface 30a makes it easier to prevent the chipping from expanding when removing the second portion 32.

[0045] The wavelength conversion member 30 may be pieced up solely by cutting with the cutting member 320, but the time required for pieced up can be shortened by combining the formation of the first groove 36 by cutting with the cutting member 320 and the cleavage of the wavelength conversion member 30 at a position overlapping with the first groove 36 in a plan view. Furthermore, the formation of the first groove 36 makes it possible to reduce the ratio of the area of ​​the first surface 30a to the area of ​​the second surface 30b in the light-emitting device 1. Therefore, a larger area of ​​the second surface 30b allows for the placement of a larger light-emitting section 60, thereby increasing the light intensity of the light-emitting device 1. Also, a smaller area of ​​the first surface 30a increases the intensity of the light emitted from the first surface 30a. When a part of the first groove 36 overlaps with the light-emitting section 60 in a plan view, it is particularly easy to reduce the ratio of the area of ​​the first surface 30a to the area of ​​the second surface 30b, resulting in a greater effect on improving light intensity. The same applies to the removal of the second part 32.

[0046] The depth D1 of the first groove 36 (see Figure 4) is preferably at least half the thickness of the wavelength conversion member 30. Because the wavelength conversion member 30 is made of a sintered body, the direction of crack propagation during fracture tends to vary. If the depth D1 of the first groove 36 is at least half the thickness of the wavelength conversion member 30, even if the direction of crack propagation varies, the distance between the bottom surface 36a of the first groove 36 and the second surface 30b is short, which reduces the degree of variation on the second surface 30b. The depth D1 of the first groove 36 is more preferably at least two-thirds the thickness of the wavelength conversion member 30. The same applies to the depth of the second groove 37.

[0047] Furthermore, it is preferable that the depth D1 of the first groove 36 is greater than the depth of the first crack 131 and the depth of the second crack 132, with respect to the first surface 30a. Between the first surface 30a and the ends of the first crack 131 and the second crack 132 on the second surface 30b side, even if chipping occurs in the wavelength conversion member 30, the expansion of the chipping can be stopped by the first crack 131 or the second crack 132. Chipping is less likely to occur in the wavelength conversion member 30 between the second surface 30b and the ends of the first crack 131 and the second crack 132 on the second surface 30b side. In addition, even if the direction of crack propagation varies when the wavelength conversion member 30 is fractured, the degree of variation on the second surface 30b can be reduced. The same applies to the depth of the second groove 37.

[0048] (Second Embodiment) A second embodiment will now be described. The second embodiment differs from the first embodiment mainly in that a substrate is used as the plate material instead of the wavelength conversion member 30. Figures 9 to 14 are cross-sectional views illustrating the manufacturing method of the element according to the second embodiment. Figures 15 to 16 are plan views illustrating the manufacturing method of the element according to the second embodiment.

[0049] <Process for preparing substrate 90> First, a substrate 90 is prepared as a plate material, as shown in Figure 9. The substrate 90 has a first surface 90a and a second surface 90b located on the opposite side of the first surface 90a. The substrate 90 is, for example, a sapphire substrate and has an a-axis and an m-axis that are parallel to the first surface 90a and the second surface 90b and perpendicular to each other. The a-axis is perpendicular to the a-plane of the sapphire crystal, and the m-axis is perpendicular to the m-plane of the sapphire crystal. The first direction is parallel to the a-axis of the substrate 90, and the second direction is parallel to the m-axis of the substrate 90.

[0050] Next, a structure 112 is prepared, which includes a substrate 90, a light-emitting part 60, a conductive layer 55, a first insulating film 51, a second insulating film 52, a p-side electrode 71, an n-side electrode 72, a p-side external connection electrode 81, and an n-side external connection electrode 82. The configuration of the light-emitting part 60, the conductive layer 55, the first insulating film 51, the second insulating film 52, the p-side electrode 71, the n-side electrode 72, the p-side external connection electrode 81, and the n-side external connection electrode 82 is the same as that of the structure 111 in the first embodiment. The second surface 90b of the substrate 90 and the surface 10a of the semiconductor layer 10 face each other.

[0051] <Steps for forming the first and second modified sections, and steps for forming the third and fourth modified sections> After the step of preparing the structure 112, the support members 40 are attached to the p-side external connection electrode 81 and the n-side external connection electrode 82 in the same manner as in the first embodiment, as shown in Figure 10.

[0052] Next, as shown in Figure 11, laser beams L1 and L2 are shone into the interior of the substrate 90. Figures 11 and 12 show enlarged views of the region R2 indicated by the dashed line in Figure 10. For example, laser beams L1 and L2 are shone into the interior of the substrate 90 from the first surface 90a side. In this embodiment, as shown in Figures 11 and 15, in a plan view perpendicular to the first surface 90a, laser beam L1 is scanned over the portion that overlaps with one of the light-emitting parts 60 adjacent to the gap 61, and laser beam L2 is scanned over the portion that overlaps with the other light-emitting part 60. Laser beams L1 and L2 may also be scanned so as to overlap only the gap 61 in a plan view perpendicular to the first surface 90a. In Figure 11, laser beams L1 and L2 are scanned in a first direction that penetrates the plane of the paper.

[0053] The laser beam L1 is focused at a specific depth within the substrate 90, concentrating its energy at that location and forming a first modified portion 221 inside the substrate 90. Similarly, the laser beam L2 is focused at a specific depth within the substrate 90, concentrating its energy at that location and forming a second modified portion 222 at a location away from the first modified portion 221 in a plan view. As the laser beams L1 and L2 are scanned in a first direction, the first modified portion 221 and the second modified portion 222 are formed along the first direction, as shown in Figure 15. The first modified portion 221 and the second modified portion 222 are more brittle than the parts where neither the laser beam L1 nor the laser beam L2 is focused. As shown in Figure 11, the first modified portion 221 formed by irradiation with the laser beam L1 generates stress, and this stress causes a first crack 231 to form inside the substrate 90. The second modified portion 222 formed by irradiation with laser light L2 generates stress, and this stress causes a second crack 232 to form inside the substrate 90. The first crack 231 extends from the first modified portion 221 in the thickness direction of the substrate 90, and the second crack 232 extends from the second modified portion 222 in the thickness direction of the substrate 90.

[0054] Next, similar to the irradiation of laser beams L1 and L2, laser beams are irradiated into the interior of the substrate 90 along a second direction intersecting the first direction, and as shown in Figure 15, a third modified portion 223 is formed inside the substrate 90 along the second direction, and a fourth modified portion 224 is formed inside the substrate 90 along the second direction at a position away from the third modified portion 223 in a plan view.

[0055] Note that in Figures 15 and 16, only the substrate 90 and the light-emitting part 60 are shown, and other components are omitted. Also, in Figures 15 and 16, the first modified part 221, the second modified part 222, the third modified part 223 and the fourth modified part 224 are shown as points, but adjacent first modified parts 221 may be connected to form the first modified part 221 in a linear shape, adjacent second modified parts 222 may be connected to form the second modified part 222 in a linear shape, adjacent third modified parts 223 may be connected to form the third modified part 223 in a linear shape, and adjacent fourth modified parts 224 may be connected to form the fourth modified part 224 in a linear shape.

[0056] <Process for separating the substrate 90 into individual pieces> [Steps to remove the first part (step to form the first groove), step to remove the second part (step to form the second groove)] After the steps of forming the first modified portion 221 and the second modified portion 222, and the steps of forming the third modified portion 223 and the fourth modified portion 224, as shown in Figures 12 and 16, the first portion 91 between the first modified portion 221 and the second modified portion 222 of the substrate 90 is removed in a plan view. For example, the first groove 96 is formed by removing a portion of the substrate 90 between the first modified portion 221 and the second modified portion 222 from the first surface 90a side. The first groove 96 can be formed by machining (cutting) the substrate 90 using a cutting member 320 such as a dicing blade. For example, the first groove 96 is formed so that a portion of it overlaps with the light-emitting portion 60 in a plan view. The first groove 96 may also be formed so that it does not overlap with the light-emitting portion 60 in a plan view. In Figure 12, the first groove 96 extends in a first direction that penetrates the plane of the paper. The first groove 96 is defined by a bottom surface 96a and a side surface 96b that connects the first surface 90a and the bottom surface 96a.

[0057] Next, similar to the removal of the first portion 91, the second portion 92 between the third modified portion 223 and the fourth modified portion 224 of the substrate 90 is removed in a plan view. For example, similar to the formation of the first groove 96, the second groove 97 is formed by removing a portion of the substrate 90 between the third modified portion 223 and the fourth modified portion 224 from the first surface 90a side. The second groove 97 can also be formed by machining (cutting) the substrate 90. In Figure 16, the first groove 96 and the second groove 97 are shown with dashed lines.

[0058] [Process of cutting the substrate 90] After the steps of forming the first groove 96 and the second groove 97, the substrate 90 is fractured starting from the first groove 96. For example, as shown in Figure 13, the substrate 90 can be fractured by pressing the support member 40 with the pressing member 310. For example, in a plan view, a pressing force is applied to the support member 40 from the surface 40b side by the pressing member 310 at a position that overlaps with the first groove 96. When the support member 40 receives a pressing force from the surface 40b side, a large tensile stress parallel to the first surface 90a acts on the substrate 90. As a result, the substrate 90 begins to crack from the first surface 90a side, starting from the first groove 96. In this way, the substrate 90 can be fractured at a position that overlaps with the first groove 96 in a plan view. Furthermore, by applying a pressing force from the pressing member 310 to the support member 40 from the surface 40b side at a position that overlaps with the second groove 97 in a plan view, the substrate 90 can be cut at a position that overlaps with the second groove 97 in a plan view.

[0059] After the step of cutting the substrate 90, the light-emitting part 60 is separated from the support member 40, as shown in Figure 14, similar to the first embodiment. As a result, a light-emitting device 2, which is an example of a plurality of elements including the light-emitting part 60, is obtained from the structure 112.

[0060] The same effects as those of the first embodiment can be obtained with the second embodiment as well.

[0061] In the second embodiment, the first groove 96 is formed along the a-axis of the sapphire, and the second groove 97 is formed along the m-axis of the sapphire. Furthermore, sapphire is more prone to cracking along the a-axis than along the m-axis. For this reason, the depth of the first groove 96 parallel to the a-axis is preferably less than half the thickness of the substrate 90, and the depth of the second groove 97 parallel to the m-axis is preferably half or more the thickness of the substrate 90. Even if the depth of the first groove 96 is less than half the thickness of the substrate 90, the substrate 90 can be easily cut afterward, and the time required to form the first groove 96 can be shortened. On the other hand, by making the depth of the second groove 97 half or more the thickness of the substrate 90, the subsequent cutting can be performed stably.

[0062] Furthermore, the element is not limited to light-emitting devices. For example, the element may be a semiconductor device such as a light-receiving device, memory device, or control device. Also, the element may simply be a plate material that has been divided into individual pieces.

[0063] (experiment) Here, the experiments conducted by the present inventor will be described. In these experiments, a structure 112 was prepared in accordance with the second embodiment. As the first condition, a first modified portion 221 and a second modified portion 222 were formed on a portion of the first surface 90a of the substrate 90 in accordance with the second embodiment, and then a groove was formed along the first direction. For comparison, as the second condition, a groove was formed along the first direction on another portion of the first surface 90a without forming the first modified portion 221 and the second modified portion 222. A sapphire substrate with a thickness of 150 μm was used as the substrate 90, and a dicing blade with a blade thickness of 30 μm was used as the cutting member 320. When forming the groove, the cutting speed in the first direction was set to 5 mm / second, the rotation speed of the dicing blade was set to 10 krpm, and the groove depth was set to 80 μm. After forming the groove, the substrate 90 around the groove was observed. Figure 17 shows the observation results around the groove formed under condition 1. Figure 18 shows the observation results around the groove formed under condition 2.

[0064] As is clear from comparing Figure 17 and Figure 18, the chipping around groove 301 formed under condition 1 was slight, while significant chipping occurred around groove 302 formed under condition 2. Note that a thin chip is visible below the plane of the paper in Figure 17; this is because grooves 301 and 302 were formed on the same sample, and the tip of the chip originating from groove 302 in Figure 18 is reflected in the image.

[0065] This specification includes the following embodiments. Section 1. A step of preparing a board material having a first surface, A step of scanning a laser beam along a first direction parallel to the first surface to form a first modified portion inside the plate material along the first direction, A step of scanning a laser beam along the first direction and forming a second modified portion along the first direction at a position in the interior of the plate material, away from the first modified portion, in a plan view, The process of dividing the aforementioned plate material into individual pieces, It has, A method for manufacturing an element, wherein the step of separating the elements comprises removing a first portion between the first modified portion and the second modified portion of the plate material in a plan view. Section 2. The method for manufacturing an element according to item 1, wherein the first part is separate from the first modification part and the second modification part. Section 3. The aforementioned plate material further has a second surface located opposite to the first surface, In the process of forming the first modified portion, the first modified portion is formed at a position closer to the first surface than to the second surface. In the process of forming the second modified portion, the second modified portion is formed at a position closer to the first surface than the second surface. A method for manufacturing an element according to item 1 or 2, wherein in the step of removing the first portion, the plate material is removed from the first surface side. Section 4. The aforementioned step of separating the pieces is, The process of forming a first groove in the plate material by removing the first portion, A step of cutting the plate material at a position that overlaps with the first groove in a plan view, A method for manufacturing an element according to item 3 above, further comprising the above. Section 5. The aforementioned plate material is made of a sintered body, The method for manufacturing an element according to item 4, wherein the depth of the first groove is 1 / 2 times or more the thickness of the plate material. Section 6. The aforementioned plate material is made of sapphire. A step of scanning a laser beam along a second direction intersecting the first direction to form a third modified portion inside the plate material along the second direction, A step of scanning a laser beam along the second direction and forming a fourth modified portion along the second direction at a position in the interior of the plate material away from the third modified portion in a plan view, In a plan view, the process involves removing the second portion between the third modified portion and the fourth modified portion of the plate material, It has, The step of removing the second part is: A step of forming a second groove in the plate material by removing the aforementioned plate material, A step of cutting the plate material at a position that overlaps with the second groove in a plan view, It has, The first direction is parallel to the a-axis of the plate material, The second direction is parallel to the m-axis of the plate material, The depth of the first groove is less than half the thickness of the plate material. The method for manufacturing an element according to item 4, wherein the depth of the second groove is 1 / 2 times or more the thickness of the plate material. Section 7. In the process of forming the first modified portion, a first crack extending from the first modified portion is formed in the plate material. In the process of forming the second modified portion, a second crack extending from the second modified portion is formed in the plate material. A method for manufacturing an element according to any one of items 4 to 6, wherein the depth of the first groove is greater than the depth of the first crack and the depth of the second crack. Section 8. The aforementioned plate material has a second surface located opposite to the first surface, A method for manufacturing an element according to any one of items 1 to 7, wherein a semiconductor layer is arranged on the second surface side of the plate material. [Explanation of Symbols]

[0066] 1, 2: Light-emitting device 10: Semiconductor layer 10a: Surface 11: Side semiconductor layer 12:Active layer 13: Side semiconductor layer 20: Translucent layer 30: Wavelength conversion component 30a, 90a: 1st page 30b, 90b: 2nd side 31, 91: Part 1 32, 92: 2nd part 36, 96: 1st groove 37, 97: 2nd groove 40: Support member 60: Light-emitting part 90: Circuit board 121, 221: First modification section 122, 222: Second Modification Section 123, 223: Third Modification Section 124, 224: Fourth Modification Section 131, 231: First Fissure 132, 232: Second Fissure 301, 302: Groove L1, L2: Laser light

Claims

1. A step of preparing a board material having a first surface, A step of scanning a laser beam along a first direction parallel to the first surface to form a first modified portion inside the plate material along the first direction, A step of scanning a laser beam along the first direction and forming a second modified portion along the first direction at a position in the interior of the plate material, away from the first modified portion, in a plan view, The process of dividing the aforementioned plate material into individual pieces, It has, A method for manufacturing an element, wherein the step of separating the elements comprises removing a first portion between the first modified portion and the second modified portion of the plate material in a plan view.

2. The method for manufacturing an element according to claim 1, wherein the first portion is separated from the first modification portion and the second modification portion.

3. The aforementioned plate material further has a second surface located opposite to the first surface, In the process of forming the first modified portion, the first modified portion is formed at a position closer to the first surface than to the second surface. In the process of forming the second modified portion, the second modified portion is formed at a position closer to the first surface than the second surface. A method for manufacturing an element according to claim 1 or 2, wherein in the step of removing the first portion, the plate material is removed from the first surface side.

4. The aforementioned process of separating into individual pieces is, The process of forming a first groove in the plate material by removing the first portion, A step of cutting the plate material at a position that overlaps with the first groove in a plan view, A method for manufacturing an element according to claim 3, further comprising the above.

5. The aforementioned plate material is made of a sintered body, The method for manufacturing an element according to claim 4, wherein the depth of the first groove is at least half the thickness of the plate material.

6. The aforementioned plate material is made of sapphire. A step of scanning a laser beam along a second direction intersecting the first direction to form a third modified portion inside the plate material along the second direction, A step of scanning a laser beam along the second direction and forming a fourth modified portion along the second direction at a position in the interior of the plate material away from the third modified portion in a plan view, In a plan view, the process involves removing the second portion between the third modified portion and the fourth modified portion of the plate material, It has, The step of removing the second part is: A step of forming a second groove in the plate material by removing the aforementioned plate material, A step of cutting the plate material at a position that overlaps with the second groove in a plan view, It has, The first direction is parallel to the a-axis of the plate material, The second direction is parallel to the m-axis of the plate material, The depth of the first groove is less than half the thickness of the plate material. The method for manufacturing an element according to claim 4, wherein the depth of the second groove is 1 / 2 times or more the thickness of the plate material.

7. In the process of forming the first modified portion, a first crack extending from the first modified portion is formed in the plate material. In the process of forming the second modified portion, a second crack extending from the second modified portion is formed in the plate material. The method for manufacturing an element according to claim 4, wherein the depth of the first groove is greater than the depth of the first crack and the depth of the second crack.

8. The aforementioned plate material has a second surface located opposite to the first surface, The method for manufacturing an element according to claim 1 or 2, wherein a semiconductor layer is arranged on the second surface side of the plate material.

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