Processing head and laser processing equipment

Abstract

To provide a processing head capable of processing a processing target object with high accuracy.SOLUTION: A processing head includes a first laser array element in which a plurality of first photonic crystal lasers is arrayed in a first direction, and a second laser array element in which a plurality of second photonic crystal lasers is arrayed in the first direction. The first laser array element and the second laser array element irradiate a processing target object with laser light in a third direction crossing the first direction and a second direction while being moved relatively in the second direction crossing the first direction. A second end photonic crystal laser and a second intermediate photonic crystal laser overlap each other viewed from the second direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a processing head and a laser processing apparatus.

Background Art

[0002] A photonic crystal surface emitting laser (PCSEL) that utilizes the photonic crystal effect is known. The PCSEL is applied, for example, to a processing head of a laser processing apparatus that irradiates a processing object with laser light.

[0003] For example, Patent Document 1 describes a laser module including a plurality of PCSELs. The PCSEL has a substrate and a photonic crystal layer laminated on the substrate. The photonic crystal layer is produced by etching a slab layer to form holes.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a processing head including a plurality of PCSELs as described above, it is difficult for the PCSEL provided in the peripheral portion of the substrate to have desired characteristics such as a shifted oscillation wavelength. For example, when the substrate on which the photonic crystal layer is laminated is warped, the etching amount becomes larger in the peripheral portion than in the central portion of the slab layer, and holes with a desired diameter cannot be formed. Therefore, in the peripheral portion, a PCSEL with desired characteristics cannot be formed. If a PCSEL with desired characteristics cannot be formed, the processing accuracy of the processing head decreases.

Means for Solving the Problems

[0006] One embodiment of the processing head according to the present invention is: A first laser array element in which multiple first photonic crystal lasers are arranged in a first direction, A second laser array element in which multiple second photonic crystal lasers are arranged in the first direction, It has, The first laser array element and the second laser array element are moved relative to the workpiece in a second direction intersecting the first direction, and irradiate the workpiece with laser light in a third direction intersecting the first and second directions. The first end photonic crystal laser among the plurality of first photonic crystal lasers is located in the direction most opposite to the first direction among the plurality of first photonic crystal lasers, The second-end photonic crystal laser among the plurality of first photonic crystal lasers is the one located most in the first direction among the plurality of first photonic crystal lasers, The first intermediate photonic crystal laser among the plurality of first photonic crystal lasers is located between the first end photonic crystal laser and the second end photonic crystal laser. The third-end photonic crystal laser among the plurality of second photonic crystal lasers is located in the opposite direction to the plurality of second photonic crystal lasers. The fourth-end photonic crystal laser among the plurality of second photonic crystal lasers is the one located furthest in the first direction among the plurality of second photonic crystal lasers, The second intermediate photonic crystal laser among the plurality of second photonic crystal lasers is located between the third-end photonic crystal laser and the fourth-end photonic crystal laser. Viewed from the second direction, the second end photonic crystal laser and the second intermediate photonic crystal laser overlap.

[0007] One embodiment of the laser processing apparatus according to the present invention is: It has one embodiment of the processing head described above. [Brief explanation of the drawing]

[0008] [Figure 1] A schematic plan view showing the machining head according to the first embodiment. [Figure 2] A schematic plan view showing the first photonic crystal laser of the processing head according to the first embodiment. [Figure 3] A schematic cross-sectional view showing the first photonic crystal laser of the processing head according to the first embodiment. [Figure 4] A schematic cross-sectional view showing the manufacturing process of a processing head according to the first embodiment. [Figure 5] A schematic cross-sectional view showing the manufacturing process of a processing head according to the first embodiment. [Figure 6] A schematic cross-sectional view showing the manufacturing process of a processing head according to the first embodiment. [Figure 7] A schematic cross-sectional view showing the manufacturing process of a processing head according to the first embodiment. [Figure 8] A schematic plan view showing a machining head according to a first modified example of the first embodiment. [Figure 9] A schematic plan view showing a machining head according to a second modified example of the first embodiment. [Figure 10] A schematic plan view showing the first photonic crystal laser of a processing head according to a second modification of the first embodiment. [Figure 11] A schematic perspective view showing a laser processing apparatus according to the second embodiment. [Figure 12] Functional block diagram of a laser processing apparatus according to the second embodiment. [Modes for carrying out the invention]

[0009] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. The embodiments described below are not intended to unduly limit the scope of the present invention as described in the claims. Furthermore, not all of the configurations described below are necessarily essential components of the present invention.

[0010] 1. First Embodiment 1.1. Processing Head First, the processing head according to the first embodiment will be described with reference to the drawings. FIG. 1 is a plan view schematically showing a processing head 100 according to the first embodiment. In FIG. 1, the X-axis, the Y-axis, and the Z-axis are illustrated as three axes orthogonal to each other.

[0011] As shown in FIG. 1, the processing head 100 has, for example, a substrate 10 and a laser array element 20.

[0012] The substrate 10 supports the laser array element 20. The material of the substrate 10 is not particularly limited.

[0013] The laser array element 20 is provided on the substrate 10. The laser array element 20 is, for example, bonded to the substrate 10. In the illustrated example, the planar shape of the laser array element 20 is a rectangle having a long side parallel to the X-axis.

[0014] The laser array element 20 is relatively moved in a second direction intersecting the first direction with respect to a processing object not shown. With the processing object fixed, the laser array element 20 may move, or with the laser array element 20 fixed, the processing object may move. The laser array element 20 is, for example, moved together with the substrate 10. The laser array element 20 and the substrate 10 are moved by a moving mechanism not shown. While being relatively moved with respect to the processing object, the laser array element 20 irradiates the processing object with laser light in three directions intersecting the first direction and the second direction. The first direction, the second direction, and the third direction are, for example, directions orthogonal to each other. In the illustrated example, the first direction is the +X-axis direction. The second direction is the +Y-axis direction. The third direction is the +Z-axis direction.

[0015] While being relatively moved with respect to the processing object, the laser array element 20 irradiates the processing object with laser light in three directions intersecting the first direction and the second direction. [[ID=2"]] The The first direction, the second direction, and the third direction are, for example, directions orthogonal to each other. In the illustrated example, the first direction is the +X-axis direction. The second direction is the +Y-axis direction. The third direction is the +Z-axis direction.

[0016] Multiple laser array elements 20 are provided. The number of laser array elements 20 is not particularly limited, as long as there are multiple elements. In the illustrated example, five laser array elements 20 are provided as the first laser array element 20a, the second laser array element 20b, the third laser array element 20c, the fourth laser array element 20d, and the fifth laser array element 20e.

[0017] The first laser array element 20a, the third laser array element 20c, and the fifth laser array element 20e are arranged in the +X axis direction. The third laser array element 20c is located between the first laser array element 20a and the fifth laser array element 20e. In the illustrated example, the third laser array element 20c is located further in the +X axis direction than the first laser array element 20a. The distance between the first laser array element 20a and the third laser array element 20c and the distance between the third laser array element 20c and the fifth laser array element 20e are, for example, the same.

[0018] The second laser array element 20b and the fourth laser array element 20d are arranged in the +X axis direction. In the illustrated example, the fourth laser array element 20d is positioned further in the +X axis direction than the second laser array element 20b. The distance between the second laser array element 20b and the fourth laser array element 20d is the same as the distance between the first laser array element 20a and the third laser array element 20c, for example.

[0019] The second laser array element 20b is located in the -Y axis direction of the laser array elements 20a and 20c. The fourth laser array element 20d is located in the -Y axis direction of the laser array elements 20c and 20e.

[0020] The first laser array element 20a has multiple first photonic crystal lasers 31. The second laser array element 20b has multiple second photonic crystal lasers 32. The third laser array element 20c has multiple third photonic crystal lasers 33. The fourth laser array element 20d has multiple fourth photonic crystal lasers 34. The fifth laser array element 20e has multiple fifth photonic crystal lasers 35. The photonic crystal lasers 31, 32, 33, 34, and 35 are PCSELs. Hereinafter, "photonic crystal laser" will also be referred to as "PCSEL".

[0021] The planar shape of PCSEL31,32,33,34,35 is, for example, a square. The dimensions of PCSEL31,32,33,34,35 are, for example, the same as each other when viewed from the Z-axis direction.

[0022] Multiple first PCSEL31 units are provided. The number of first PCSEL31 units is not particularly limited, as long as three or more are provided. In the illustrated example, five first PCSEL31 units are provided. Similarly, multiple units of each of PCSEL32, 33, 34, and 35 are provided.

[0023] Multiple first PCSEL31s are arranged in the X-axis direction with a first pitch P. Multiple first PCSEL31s are arranged in a straight line. The "first pitch P" is the distance between the centers of adjacent first PCSEL31s in the X-axis direction. The "center of the first PCSEL31" is the center of the circle if the planar shape of the first PCSEL31 is a circle, and the center of the smallest inclusion circle if the planar shape of the first PCSEL31 is not a circle. For example, if the planar shape of the first PCSEL31 is a polygon, the center of the smallest circle that contains the polygon is the center of the polygon, and if the planar shape of the first PCSEL31 is an ellipse, the center of the smallest circle that contains the ellipse is the center of the ellipse.

[0024] Similarly, multiple second PCSEL32, multiple third PCSEL33, multiple fourth PCSEL34, and multiple fifth PCSEL35 are arranged in the X-axis direction at a first pitch P. Multiple second PCSEL32 are arranged linearly. Multiple third PCSEL33 are arranged linearly. Multiple fourth PCSEL34 are arranged linearly. Multiple fifth PCSEL35 are arranged linearly.

[0025] The first end PCSEL31a of the multiple first PCSEL31s is located furthest in the -X direction. The second end PCSEL31b of the multiple first PCSEL31s is located furthest in the +X direction. The first intermediate PCSEL31c of the multiple first PCSEL31s is located between the first end PCSEL31a and the second end PCSEL31b. In the illustrated example, three first intermediate PCSEL31c are provided.

[0026] The third end PCSEL32a of the multiple second PCSEL32s is located furthest in the -X direction. The fourth end PCSEL32b of the multiple second PCSEL32s is located furthest in the +X direction. The second intermediate PCSEL32c of the multiple second PCSEL32s is located between the third end PCSEL32a and the fourth end PCSEL32b. In the illustrated example, three second intermediate PCSEL32c are provided.

[0027] The fifth end PCSEL33a of the multiple third PCSEL33s is located furthest in the -X direction. The sixth end PCSEL33b of the multiple third PCSEL33s is located furthest in the +X direction. The third intermediate PCSEL33c of the multiple third PCSEL33s is located between the fifth end PCSEL33a and the sixth end PCSEL33b. In the illustrated example, three third intermediate PCSEL33c are provided.

[0028] Of the multiple fourth PCSEL34s, the seventh end PCSEL34a is located furthest in the -X direction. Of the multiple fourth PCSEL34s, the eighth end PCSEL34b is located furthest in the +X direction. The fourth intermediate PCSEL34c is located between the seventh end PCSEL34a and the eighth end PCSEL34b. In the illustrated example, three fourth intermediate PCSEL34c are provided.

[0029] Of the multiple fifth PCSEL35s, the ninth end PCSEL35a is located furthest in the -X direction. Of the multiple fifth PCSEL35s, the tenth end PCSEL35b is located furthest in the +X direction. The fifth intermediate PCSEL35c is located between the ninth end PCSEL35a and the tenth end PCSEL35b. In the illustrated example, there are three fifth intermediate PCSEL35c.

[0030] Viewed from the +Y axis direction, the second end PCSEL31b and the second intermediate PCSEL32c overlap. In the illustrated example, the second end PCSEL31b overlaps with the second intermediate PCSEL32c that is located furthest in the -X axis direction among the multiple second intermediate PCSEL32c.

[0031] Viewed from the +Y axis direction, the third end PCSEL32a and the first intermediate PCSEL31c overlap. In the illustrated example, the third end PCSEL32a overlaps with the first intermediate PCSEL31c that is furthest along the +X axis among the multiple first intermediate PCSEL31c.

[0032] Viewed from the +Y axis direction, the fourth end PCSEL32b and the third intermediate PCSEL33c overlap. In the illustrated example, the fourth end PCSEL32b and the third intermediate PCSEL33c that is furthest along the -X axis among the multiple third intermediate PCSEL33c components overlap.

[0033] Viewed from the +Y axis direction, the fifth end PCSEL33a and the second intermediate PCSEL32c overlap. In the illustrated example, the fifth end PCSEL33a overlaps with the second intermediate PCSEL32c that is located furthest in the +X axis direction among the multiple second intermediate PCSEL32c.

[0034] Viewed from the +Y axis direction, the sixth end PCSEL33b and the fourth intermediate PCSEL34c overlap. In the illustrated example, the sixth end PCSEL33b overlaps with the fourth intermediate PCSEL34c that is located furthest in the -X axis direction among the multiple fourth intermediate PCSEL34c.

[0035] Viewed from the +Y axis direction, the 7th end PCSEL34a and the 3rd intermediate PCSEL33c overlap. In the illustrated example, the 7th end PCSEL34a overlaps with the 3rd intermediate PCSEL33c that is furthest along the +X axis among the multiple 3rd intermediate PCSEL33c.

[0036] Viewed from the +Y axis direction, the 8th end PCSEL34b and the 5th intermediate PCSEL35c overlap. In the illustrated example, the 8th end PCSEL34b overlaps with the 5th intermediate PCSEL35c that is located furthest in the -X axis direction among the multiple 5th intermediate PCSEL35c units.

[0037] Viewed from the +Y axis direction, the 9th end PCSEL35a and the 4th intermediate PCSEL34c overlap. In the illustrated example, the 9th end PCSEL35a overlaps with the 4th intermediate PCSEL34c that is located furthest in the +X axis direction among the multiple 4th intermediate PCSEL34c.

[0038] Viewed from the Y-axis direction, the center α of the second end PCSEL31b and the center β of the second intermediate PCSEL32c overlap. In this way, of the two PCSELs that overlap when viewed from the Y-axis direction, the centers of one PCSEL and the centers of the other PCSEL overlap.

[0039] The end PCSEL31a,31b,32a,32b,33a,33b,34a,34b,35a,35b are not driven. The intermediate PCSEL31c,32c,33c,34c,35c are driven.

[0040] Here, Figure 2 is a schematic plan view showing one first PCSEL 31. Figure 3 is a schematic cross-sectional view of one first PCSEL 31 taken along line III-III in Figure 2. PCSELs 32, 33, 34, and 35 have basically the same configuration as the first PCSEL 31.

[0041] As shown in Figures 2 and 3, the first PCSEL 31 includes, for example, a DBR (Distributed Bragg Reflector) layer 41, a first semiconductor layer 42, a first guide layer 43, a quantum well layer 44, a second guide layer 45, a second semiconductor layer 46, a substrate 47, a first electrode 50, and a second electrode 52.

[0042] The DBR layer 41 reflects the light generated in the quantum well layer 44. In the illustrated example, the DBR layer 41 reflects the light generated in the quantum well layer 44 in the direction of the +Z axis.

[0043] The first semiconductor layer 42 is provided on the DBR layer 41, as shown in Figure 3. The first semiconductor layer 42 is provided between the DBR layer 41 and the first guide layer 43. The first semiconductor layer 42 is a first conductivity type semiconductor layer. The first semiconductor layer 42 is, for example, a Mg-doped p-type semiconductor layer.

[0044] In "1.1. Machining Head," when the quantum well layer 44 is used as the reference point in the Z-axis direction, the direction from the quantum well layer 44 toward the second guide layer 45 is described as "up," and the direction from the quantum well layer 44 toward the first guide layer 43 is described as "down." The direction perpendicular to the Z-axis direction is also called the "in-plane direction."

[0045] The first guide layer 43 is provided on the first semiconductor layer 42. The first guide layer 43 is provided between the first semiconductor layer 42 and the quantum well layer 44. The first guide layer 43 has an SL (Semiconductor Superlattice) structure composed of, for example, an i-type GaN layer and an InGaN layer that are not intentionally doped with impurities. The number of GaN layers and InGaN layers constituting the first guide layer 43 is not particularly limited.

[0046] The first guide layer 43 is provided with an opening 60. The opening 60 is, for example, a void. In the example shown in Figure 2, opening 60 The planar shape is a circle. The diameter of the aperture 60 is, for example, between 50 nm and 500 nm.

[0047] The "diameter of the opening 60" refers to the diameter of the opening 60 if its planar shape is a circle, and the diameter of the smallest inclusion circle if the planar shape of the opening 60 is not a circle. For example, if the planar shape of the opening 60 is a polygon, the diameter of the smallest circle that contains the polygon is the diameter of the smallest circle that contains the polygon is the diameter of the ellipse.

[0048] Multiple openings 60 are provided. The multiple openings 60 are spaced apart from each other. The spacing between adjacent openings 60 is, for example, 1 nm to 500 nm. The multiple openings 60 are arranged in a predetermined direction at a predetermined pitch when viewed from the Z-axis direction. The multiple openings 60 are arranged, for example, in a triangular lattice or a square lattice. In the illustrated example, multiple opening 60 The elements are arranged in a square lattice. Multiple openings 60 can exhibit a photonic crystal effect.

[0049] The "pitch of the openings 60" refers to the distance between the centers of adjacent openings 60 in a given direction. The "center of the opening 60" refers to the center of the circle if the planar shape of the opening 60 is a circle, and to the center of the smallest inclusion circle if the planar shape of the opening 60 is not a circle. For example, if the planar shape of the opening 60 is a polygon, the center of the opening 60 is the center of the smallest circle that contains the polygon, and if the planar shape of the opening 60 is an ellipse, the center of the smallest circle that contains the ellipse.

[0050] The quantum well layer 44 is provided on the first guide layer 43. The quantum well layer 44 is provided between the first guide layer 43 and the second guide layer 45. The quantum well layer 44 generates light when an electric current is injected. The quantum well layer 44 has, for example, a well layer and a barrier layer. The well layer and the barrier layer are i-type semiconductor layers that are not intentionally doped with impurities. The well layer is, for example, an InGaN layer. The barrier layer is, for example, a GaN layer. The quantum well layer 44 has an MQW (Multiple Quantum Well) structure composed of the well layer and the barrier layer.

[0051] The number of well layers and barrier layers constituting the quantum well layer 44 is not particularly limited. For example, there may be only one well layer, in which case the quantum well layer 44 has an SQW (Single Quantum Well) structure.

[0052] The second guide layer 45 is provided on the quantum well layer 44. The second guide layer 45 is provided between the quantum well layer 44 and the second semiconductor layer 46. The second guide layer 45 has an SL structure composed of, for example, an i-type GaN layer and an InGaN layer that are not intentionally doped with impurities. The number of GaN layers and InGaN layers constituting the second guide layer 45 is not particularly limited. The first guide layer 43 and the second guide layer 45 have the function of increasing the optical confinement coefficient of the first PCSEL 31.

[0053] Although not shown in the diagram, the multiple openings 60 may not be provided in the first guide layer 43, but rather in the second guide layer 45.

[0054] The second semiconductor layer 46 is Second guide layer 45 The second semiconductor layer 46 is provided on top of the first semiconductor layer 44. The second semiconductor layer 46 is a semiconductor layer of a second conductivity type different from the first conductivity type. The second semiconductor layer 46 is, for example, a Si-doped n-type GaN layer. The first semiconductor layer 42 and the second semiconductor layer 46 are cladding layers that have the function of confining light in the quantum well layer 44.

[0055] In the first PCSEL31, a PIN diode is formed by a p-type first semiconductor layer 42, an i-type quantum well layer 44 and guide layers 43 and 45 that are not intentionally doped with impurities, and an n-type second semiconductor layer 46. In the first PCSEL31, when a forward bias voltage of the PIN diode is applied between the first electrode 50 and the second electrode 52, current is injected into the quantum well layer 44, causing recombination of electrons and holes in the quantum well layer 44. This recombination produces light emission. The light generated in the quantum well layer 44 propagates in the in-plane direction, forms a standing wave due to the photonic crystal effect of multiple apertures 60, and receives gain in the quantum well layer 44, causing laser oscillation. The first PCSEL31 then emits the +1st order diffracted light and -1st order diffracted light as laser light in the Z-axis direction.

[0056] In the first PCSEL31, the DBR layer 41 can reflect laser light directed in the -Z axis direction in the +Z axis direction. As a result, the first PCSEL31 can emit laser light in the +Z axis direction.

[0057] The substrate 47 is provided on the second semiconductor layer 46. The substrate 47 is provided between the second semiconductor layer 46 and the second electrode 52. The substrate 47 is, for example, a Si-doped n-type semiconductor substrate.

[0058] The first electrode 50 is located beneath the DBR layer 41. The DBR layer 41 may be in ohmic contact with the first electrode 50. The first electrode 50 is electrically connected to the first semiconductor layer 42 via the DBR layer 41. The first electrode 50 is, for example, constructed by stacking Ni layers and Au layers in that order from the DBR layer 41 side. The first electrode 50 is one of the electrodes for injecting current into the quantum well layer 44.

[0059] The second electrode 52 is provided on the substrate 47. The substrate 47 may be in ohmic contact with the second electrode 52. The second electrode 52 is electrically connected to the second semiconductor layer 46 via the substrate 47. The second electrode 52 is, for example, made by stacking a Cr layer, a Ni layer, and an Au layer in that order from the substrate 47 side. The second electrode 52 is the other electrode for injecting current into the quantum well layer 44.

[0060] The second electrode 52 is provided with a through-hole 54. The through-hole 54 penetrates the second electrode 52 in the Z-axis direction. In the example shown in Figure 2, the shape of the through-hole 54 is square. Light generated in the quantum well layer 44 is emitted through the through-hole 54.

[0061] For example, in a plurality of first PCSELs 31 constituting the first laser array element 20a, the DBR layer 41 is a common layer, the first semiconductor layer 42 is a common layer, the first guide layer 43 is a common layer, the quantum well layer 44 is a common layer, the second guide layer 45 is a common layer, the second semiconductor layer 46 is a common layer, and the substrate 47 is a common substrate.

[0062] In the multiple first PCSELs 31 constituting the first laser array element 20a, the first electrode 50 may be a common electrode, and the second electrode 52 may be an individual electrode. In the multiple first PCSELs 31 constituting the first laser array element 20a, the multiple first electrodes 50 may be continuous with each other, and the multiple second electrodes 52 may be separated from each other. In this case, when viewed from the Z-axis direction, the portion overlapping with the second electrode 52 and the through hole 54 constitutes one first PCSEL 31. The multiple first PCSELs 31 can be driven individually by the second electrode 52.

[0063] Alternatively, in the multiple first PCSELs 31 constituting the first laser array element 20a, the first electrodes 50 may be individual electrodes, and the second electrodes 52 may be common electrodes. In the multiple first PCSELs 31 constituting the first laser array element 20a, the multiple first electrodes 50 may be spaced apart from each other, and the multiple second electrodes 52 may be continuous from each other. In this case, when viewed from the Z-axis direction, the portion overlapping with the first electrode 50 constitutes one first PCSEL 31. The multiple first PCSELs 31 can be driven individually by the first electrodes 50.

[0064] 1.2. Method for manufacturing a processing head Next, the manufacturing method of the machining head 100 according to the first embodiment will be described with reference to the drawings. Figures 4 to 7 are schematic cross-sectional views showing the manufacturing process of the machining head 100 according to the first embodiment. For convenience, Figures 4 to 7 are shown upside down compared to Figure 3.

[0065] As shown in Figure 4, a second semiconductor layer 46, a second guide layer 45, a quantum well layer 44, and a first guide layer 43 are epitaxially grown on a substrate 47. Examples of epitaxial growth methods include MOCVD (Metal Organic Chemical Vapor Deposition) and MBE (Molecular Beam Epitaxy).

[0066] In "1.2. Method for Manufacturing the Processing Head," the direction from the quantum well layer 44 toward the first guide layer 43 is referred to as "up," and the direction from the quantum well layer 44 toward the second guide layer 45 is referred to as "down."

[0067] For example, heating during epitaxial growth and subsequent cooling can cause warping in the substrate 47. In the illustrated example, warping occurs such that the center of the substrate 47 is positioned higher than the periphery. Along with the warping of the substrate 47, warping also occurs in the second semiconductor layer 46, the second guide layer 45, the quantum well layer 44, and the first guide layer 43. For convenience, the warping of the substrate 47 is omitted in Figure 3.

[0068] As shown in Figure 5, a resist layer 2 is applied on the first guide layer 43. The resist layer 2 is applied, for example, by a spin coating method. Due to the warping of the substrate 47, the thickness of the resist layer 2 at the periphery is smaller than the thickness of the resist layer 2 at the center. Material of the resist layer 2 For example, a photoresist whose properties change when exposed to UV (ultraviolet) light.

[0069] As shown in Figure 6, the resist layer 2 is patterned. Patterning is performed, for example, by nanoimprint lithography. Nanoimprint lithography can process large areas in a single operation.

[0070] As shown in Figure 7, the first guide layer 43 is dry-etched using the resist layer 2 as a mask to form multiple openings 60 in the first guide layer 43. As described above, the thickness of the peripheral part of the resist layer 2 is smaller than the thickness of the central part of the resist layer 2, so the peripheral part of the resist layer 2 is removed during dry etching. As a result, the peripheral part of the first guide layer 43 is removed. Do After etching, the diameter D1 of the peripheral opening 60 becomes larger than the diameter D2 of the central opening 60. Subsequently, the resist layer 2 is removed by a known method.

[0071] As shown in Figure 1, after forming the opening 60, the first guide layer 43 is further epitaxially grown. This seals the opening 60. Examples of epitaxial growth methods include MOCVD and MBE.

[0072] Next, the first semiconductor layer 42 and the DBR layer 41 are epitaxially grown on the first guide layer 43 in that order. Examples of epitaxial growth methods include the MOCVD method and the MBE method.

[0073] Next, a first electrode 50 is formed on the DBR layer 41. Then, a second electrode 52 is formed on the substrate 47. The first electrode 50 and the second electrode 52 are formed, for example, by vacuum deposition. The order in which the first electrode 50 and the second electrode 52 are formed is not particularly limited.

[0074] Next, the second electrode 52 is patterned to form a through hole 54. The patterning is performed, for example, by photolithography and etching.

[0075] Through the above process, a first laser array element 20a having multiple first PCSELs 31 with substrate 47 as a common substrate can be formed.

[0076] By repeating the above steps, a second laser array element 20b having multiple second PCSELs 32, a third laser array element 20c having multiple third PCSELs 33, a fourth laser array element 20d having multiple fourth PCSELs 34, and a fifth laser array element 20e having multiple fifth PCSELs 35 can be formed.

[0077] Next, the laser array elements 20a, 20b, 20c, 20d, and 20e are bonded to the substrate 10. For example, the first electrodes 50 of the laser array elements 20a, 20b, 20c, 20d, and 20e are bonded to the substrate 10 by solder (not shown).

[0078] The processing head 100 can be manufactured through the above process.

[0079] 1.3. Effects The processing head 100 includes a first laser array element 20a in which a plurality of first PCSELs 31 are arranged in the +X axis direction, and a second laser array element 20b in which a plurality of second PCSELs 32 are arranged in the +X axis direction. The first laser array element 20a and the second laser array element 20b are moved relative to the workpiece in the +Y axis direction, and irradiate the workpiece with laser light in the +Z axis direction. When viewed from the +Y axis direction, the second end PCSEL 31b and the second intermediate PCSEL 32c overlap.

[0080] Here, since the second end PCSEL31b is located further to the periphery than the first intermediate PCSEL31c, the diameter of the aperture 60 is larger than the desired value, as described above. Therefore, in the second end PCSEL31b, the oscillation wavelength, oscillation threshold, and light intensity deviate from the desired values.

[0081] As described above, in the machining head 100, the second end PCSEL 31b and the second intermediate PCSEL 32c overlap when viewed from the +Y axis direction. Therefore, by not irradiating the laser beam from the second end PCSEL 31b, but irradiating the laser beam from the second intermediate PCSEL 32c which overlaps with the second end PCSEL 31b when viewed from the +Y axis direction, the area of ​​the workpiece through which the second end PCSEL 31b passes can be laser-machined. Consequently, the machining head 100 can machine the workpiece with high precision.

[0082] In the processing head 100, the third end PCSEL 32a and the first intermediate PCSEL 31c overlap when viewed from the +Y axis direction. Therefore, in the processing head 100, by not irradiating laser light from the third end PCSEL 32a, but irradiating laser light from the first intermediate PCSEL 31c which overlaps with the third end PCSEL 32a when viewed from the +Y axis direction, the area through which the third end PCSEL 32a of the workpiece passes can be laser processed.

[0083] The processing head 100 has a third laser array element 20c in which multiple third PCSELs 33 are arranged in the +X axis direction. The third laser array element 20c is moved relative to the workpiece in the +Y axis direction and irradiates the workpiece with laser light in the +Z axis direction. When viewed from the +Y axis direction, the fourth end PCSEL 32b and the third intermediate PCSEL 33c overlap. Therefore, in the processing head 100, by irradiating laser light from the third intermediate PCSEL 33c, which overlaps with the fourth end PCSEL 32b when viewed from the +Y axis direction, instead of irradiating laser light from the fourth end PCSEL 32b, the area through which the fourth end PCSEL 32b of the workpiece passes can be laser processed. Furthermore, by providing the third laser array element 20c, the processing area of ​​the workpiece and the production speed can be increased.

[0084] In the machining head 100, the fifth end PCSEL 33a and the second intermediate PCSEL 32c overlap when viewed from the +Y axis direction. Therefore, in the machining head 100, the laser beam is not emitted from the fifth end PCSEL 33a, but rather from the second intermediate PCSEL 32c, which overlaps with the fifth end PCSEL 33a when viewed from the +Y axis direction. This allows for laser machining of the area through which the fifth end PCSEL 33a of the workpiece passes.

[0085] In the machining head 100, the first PCSEL 31 and the third PCSEL 33 are arranged in the +X axis direction. Therefore, in the machining head 100, the size of the machining head 100 in the +Y axis direction can be reduced compared to when the first PCSEL and the third PCSEL are not arranged in the +X axis direction.

[0086] In the processing head 100, multiple first PCSELs 31 are arranged at a first pitch P, and multiple second PCSELs 32 are also arranged at a first pitch P. Therefore, the processing head 100 can irradiate the workpiece with laser light at equal intervals.

[0087] In the machining head 100, the center α of the second end PCSEL 31b and the center β of the second intermediate PCSEL 32c overlap when viewed from the +Y axis direction. Therefore, the machining head 100 can more reliably irradiate the workpiece with laser light at equal intervals.

[0088] In the above, we described an example in which a photonic crystallization effect is exhibited by forming multiple openings 60 in the first guide layer 43, but by forming multiple columnar parts... The photonic crystallization effect may be exhibited. Multiple columnar parts are formed by epitaxial growth using a mask layer (not shown) as a mask. Among the multiple columnar parts, the peripheral columnar parts are more susceptible to abnormal growth due to the excessive supply of growth gas compared to the central columnar parts. Therefore, even when the photonic crystallization effect is exhibited by forming multiple columnar parts, the oscillation wavelength, oscillation threshold, and light intensity of the second end PCSEL31b tend to deviate from the desired values. Consequently, even in such cases, the workpiece can be processed with high precision by overlapping the second end PCSEL31b and the second intermediate PCSEL32c when viewed from the +Y axis direction.

[0089] 1.4. Modified examples of machining heads 1.4.1. First Variation Next, a machining head relating to a first modified example of the first embodiment will be described with reference to the drawings. Figure 8 is a schematic plan view showing a machining head 110 relating to a first modified example of the first embodiment.

[0090] In the following description of the processing head 110 according to the first modified example of the first embodiment, components having the same function as the components of the processing head 100 according to the first embodiment described above are denoted by the same reference numerals, and their detailed descriptions are omitted. The same applies to the processing head according to the second modified example of the first embodiment, which will be described later.

[0091] In the processing head 100 described above, as shown in Figure 1, the first intermediate PCSEL 31c of the first laser array element 20a and the second intermediate PCSEL 32c of the second laser array element 20b did not overlap when viewed from the +Y axis direction.

[0092] In contrast, in the machining head 110, as shown in Figure 8, the first intermediate PCSEL 31c and the second intermediate PCSEL 32c overlap when viewed from the +Y axis direction. In the illustrated example, there are seven first intermediate PCSEL 31c and seven second intermediate PCSEL 32c.

[0093] In the illustrated example, when viewed from the +Y axis direction, the first intermediate PCSEL31c1, which is the furthest to the +X axis direction among the multiple first intermediate PCSEL31c, and the second intermediate PCSEL32c2, which is the second furthest to the -X axis direction among the multiple second intermediate PCSEL32c, overlap.

[0094] Viewed from the +Y axis direction, the first intermediate PCSEL31c2, which is the second of the multiple first intermediate PCSEL31c located in the +X axis direction, and the second intermediate PCSEL32c1, which is the furthest in the -X axis direction among the multiple second intermediate PCSEL32c, overlap. Intermediate PCSEL31c1 and 32c1 are not driven.

[0095] In the processing head 110, by not irradiating laser light from the first intermediate PCSEL 31c1 and instead irradiating laser light from the second intermediate PCSEL 32c2 which overlaps with the first intermediate PCSEL 31c1 when viewed from the Y-axis direction, the area of ​​the workpiece through which the first intermediate PCSEL 31c1 passes can be laser processed. Furthermore, by not irradiating laser light from the second intermediate PCSEL 32c1 and instead irradiating laser light from the first intermediate PCSEL 31c2 which overlaps with the second intermediate PCSEL 32c1 when viewed from the Y-axis direction, the area of ​​the workpiece through which the second intermediate PCSEL 32c1 passes can be laser processed.

[0096] 1.4.2. Second Variation Next, the machining head according to the second modified example of the first embodiment will be described with reference to the drawings. Figure 9 is a schematic plan view showing the machining head 120 according to the second modified example of the first embodiment. Figure 10 shows the first PCSEL of the machining head 120 according to the second modified example of the first embodiment. This is a schematic plan view of 31.

[0097] In the machining head 100 described above, the planar shape of the first PCSEL 31 was square, as shown in Figures 1 and 2.

[0098] In contrast, in the machining head 120, as shown in Figures 9 and 10, the planar shape of the first PCSEL 31 is circular. Similarly, the planar shapes of PCSELs 32, 33, 34, and 35 are circular.

[0099] 2. Second Embodiment Next, a laser processing apparatus according to the second embodiment will be described with reference to the drawings. Figure 11 is a schematic perspective view showing the laser processing apparatus 200 according to the second embodiment. Figure 12 is a functional block diagram of the laser processing apparatus 200 according to the second embodiment.

[0100] The laser processing apparatus 200 uses, for example, a laser melting method (Selective La This is a metal 3D printer that utilizes laser melting (SLM). As shown in Figures 11 and 12, the laser processing device 200 includes, for example, a processing head 100, a moving mechanism 210, a focusing lens 220, a stage 230, an input buffer memory 240, a storage unit 242, a processing head position detection unit 244, a base position detection unit 246, and a control unit 248.

[0101] The moving mechanism 210 supports the machining head 100, as shown in Figure 11. In the illustrated example, the machining head 100 is located in the +Z-axis direction of the moving mechanism 210. The moving mechanism 210 moves the machining head 100 in the Y-axis direction. In the illustrated example, the moving mechanism 210 has a shape that extends in the Y-axis direction. The moving mechanism 210 is configured to include, for example, a motor (not shown).

[0102] The focusing lens 220 focuses the laser light emitted from the processing head 100. In the illustrated example, the focusing lens 220 is located in the +Z axis direction of the processing head 100. The focusing lens 220 moves in the Y axis direction as the processing head 100 moves. The focusing lens 220 is supported by, for example, a moving mechanism (not shown).

[0103] The stage 230 includes, for example, a base 232 and an elevator mechanism 234. Metal particles G, which are to be processed, are supplied to the base 232. Laser light emitted from a focusing lens 220 is shone onto the metal particles G. The elevator mechanism 234 moves the base 232 in the Z-axis direction.

[0104] The input buffer memory 240 receives data related to the laser irradiation of the processing head 100, i.e., drawing pattern data, from an external information processing device (not shown). As shown in Figure 12, the input buffer memory 240 supplies the drawing pattern data to the control unit 248. The control unit 248 stores the drawing pattern data in the storage unit 242. The input buffer memory 240 and the storage unit 242 are composed of, for example, RAM (Random Access Memory) and ROM (Read Only Memory).

[0105] The machining head position detection unit 244 detects the position of the machining head 100 in the Y-axis direction and inputs the detection signal to the control unit 248. The base position detection unit 246 detects the position of the base 232 in the Z-axis direction and inputs the detection signal to the control unit 248. The machining head position detection unit 244 and the base position detection unit 246 are composed of, for example, a linear encoder, a laser length measuring device, etc.

[0106] The control unit 248 receives detection signals from the machining head position detection unit 244 and the base position detection unit 246. Based on this, the moving mechanism 210 and the elevator mechanism 234 are controlled. Furthermore, the control unit 248 reads the drawing pattern data stored in the memory unit 242 and controls the machining head 100 based on the read drawing pattern data. The control unit 248 is composed of, for example, a CPU (Central Processing Unit) and dedicated circuits.

[0107] In the laser processing apparatus 200, first, metal particles G, which will form the first layer of the workpiece, are supplied to the base 232. Next, the control unit 248 controls the moving mechanism 210 to move the processing head 100 in the +Y axis direction, and while controlling the processing head 100 based on the drawing pattern data, it performs an irradiation process to irradiate the metal particles G, which will form the first layer, with laser light. The parts of the metal particles G that are irradiated with laser light are melted and solidified.

[0108] Next, the control unit 248 controls the moving mechanism 210 to move the machining head 100 in the -Y axis direction, returning the machining head 100 to its initial position, and controls the elevator mechanism 234 of the stage 230 to move the base 232 by one layer in the +Z axis direction.

[0109] The control unit 248 then repeats the irradiation process and movement process described above until it determines, based on the drawing pattern data, that all layers of the workpiece have been formed.

[0110] After determining that all layers of the workpiece have been formed, any unmelted and unsolidified portions of the metal particles G are removed, for example, by air blowing.

[0111] As a result, it is possible to create a workpiece with the desired shape.

[0112] The laser processing device 200 has a processing head 100. Therefore, it is possible to reduce variations in the degree of melting of the metal particles G.

[0113] Unlike the case using a fiber laser, the laser processing device 200 does not require a galvanometer scanner and an fθ lens, thus enabling miniaturization and cost reduction.

[0114] It should be noted that the laser processing apparatus according to the present invention is not limited to a metal 3D printer. The laser processing apparatus according to the present invention may be, for example, a laser cleaner that removes rust and other contaminants from metal using laser light. Furthermore, the laser processing apparatus according to the present invention may be a laser annealing apparatus that heats the surface of metal or resin using laser light.

[0115] The embodiments and variations described above are examples only and are not limiting. For example, each embodiment and each variation can be combined as appropriate.

[0116] The present invention includes configurations substantially identical to those described in the embodiments, for example, configurations with the same function, method, and results, or configurations with the same purpose and effect. Furthermore, the present invention includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. Furthermore, the present invention includes configurations that produce the same effects or achieve the same purpose as those described in the embodiments. Finally, the present invention includes configurations that add known technology to the configurations described in the embodiments.

[0117] The following can be derived from the embodiments and modifications described above.

[0118] One embodiment of a machining head is: A first laser array element in which multiple first photonic crystal lasers are arranged in a first direction, A second laser array element in which multiple second photonic crystal lasers are arranged in the first direction, It has, The first laser array element and the second laser array element are moved relative to the workpiece in a second direction intersecting the first direction, and irradiate the workpiece with laser light in a third direction intersecting the first and second directions. The first end photonic crystal laser among the plurality of first photonic crystal lasers is located in the direction most opposite to the first direction among the plurality of first photonic crystal lasers, The second-end photonic crystal laser among the plurality of first photonic crystal lasers is the one located most in the first direction among the plurality of first photonic crystal lasers, The first intermediate photonic crystal laser among the plurality of first photonic crystal lasers is located between the first end photonic crystal laser and the second end photonic crystal laser. The third-end photonic crystal laser among the plurality of second photonic crystal lasers is located in the opposite direction to the plurality of second photonic crystal lasers. The fourth-end photonic crystal laser among the plurality of second photonic crystal lasers is the one located furthest in the first direction among the plurality of second photonic crystal lasers, The second intermediate photonic crystal laser among the plurality of second photonic crystal lasers is located between the third-end photonic crystal laser and the fourth-end photonic crystal laser. Viewed from the second direction, the second end photonic crystal laser and the second intermediate photonic crystal laser overlap.

[0119] This machining head allows for high-precision machining of the workpiece.

[0120] In one embodiment of the processing head, When viewed from the second direction, the third end photonic crystal laser and the first intermediate photonic crystal laser may overlap.

[0121] With this processing head, by irradiating the workpiece with laser light from a first intermediate photonic crystal laser that overlaps with the third-end photonic crystal laser when viewed from a second direction, the area through which the third-end photonic crystal laser passes can be laser-processed.

[0122] In one embodiment of the processing head, The third laser array element has multiple third photonic crystal lasers arranged in the first direction, The third laser array element moves relative to the workpiece in the second direction while irradiating the workpiece with laser light in the third direction. The fifth-end photonic crystal laser among the plurality of third photonic crystal lasers is located in the opposite direction to the plurality of third photonic crystal lasers. The sixth-end photonic crystal laser among the plurality of third photonic crystal lasers is the one located furthest in the first direction among the plurality of third photonic crystal lasers. The third intermediate photonic crystal laser among the plurality of third photonic crystal lasers is located between the fifth-end photonic crystal laser and the sixth-end photonic crystal laser. When viewed from the second direction, the fourth end photonic crystal laser and the third intermediate photonic crystal laser may overlap.

[0123] According to this processing head, when viewed from the second direction, it overlaps with the fourth-end photonic crystal laser. By irradiating the workpiece with laser light from the third intermediate photonic crystal laser, the area through which the fourth end photonic crystal laser passes can be laser-processed.

[0124] In one embodiment of the processing head, When viewed from the second direction, the fifth end photonic crystal laser and the second intermediate photonic crystal laser may overlap.

[0125] With this processing head, by irradiating the workpiece with laser light from a second intermediate photonic crystal laser that overlaps with the fifth-end photonic crystal laser when viewed from a second direction, the area through which the fifth-end photonic crystal laser passes can be laser-processed.

[0126] In one embodiment of the processing head, The first laser array element and the third laser array element may be arranged in the first direction.

[0127] This processing head allows for a reduction in the size in the second direction.

[0128] In one embodiment of the processing head, The plurality of first photonic crystal lasers are arranged in a first pitch, The plurality of second photonic crystal lasers may be arranged in the first pitch.

[0129] This processing head allows for the irradiation of the workpiece with laser light at equal intervals.

[0130] In one embodiment of the processing head, When viewed from the second direction, the center of the second end photonic crystal laser and the center of the second intermediate photonic crystal laser may overlap.

[0131] This processing head allows for more reliable and evenly spaced laser beam irradiation of the workpiece.

[0132] One embodiment of a laser processing apparatus is: It has one embodiment of the processing head described above. [Explanation of Symbols]

[0133] 2…Resist layer, 4…Aperture, 10…Substrate, 20…Laser array element, 20a…First laser array element, 20b…Second laser array element, 20c…Third laser array element, 20d…Fourth laser array element, 20e…Fifth laser array element, 31…First PCSEL, 31a…First end PCSEL, 31b…Second end PCSEL, 31c,31c1,31c2…First intermediate PCSEL, 32…Second PCSEL, 32a…Third end PCSEL, 32b…Fourth end PCSEL, 32c,32c1,32c2…Second intermediate PCSEL, 33…Third PCSEL, 33a…Fifth end PCSEL, 33b…Sixth end PCSEL, 33c…Third intermediate PCSEL, 34...4th PCSEL, 34a...7th end PCSEL, 34b...8th end PCSEL, 34c...4th intermediate PCSEL, 35...5th PCSEL, 35a...9th end PCSEL, 35b...10th end PCSEL, 35c...5th intermediate PCSEL, 41...DBR layer, 42...1st semiconductor layer, 43...1st guide layer, 44...Quantum well layer, 45...2nd guide layer, 46...2nd semiconductor layer, 47...Substrate, 50...1st electrode, 52...2nd electrode, 54...Through hole, 60...Opening, 100, 110, 120...Processing head, 200...Laser processing device, 210...Movement mechanism, 220...Focusing lens, 230...Stage, 232...Base, 234...Elevator mechanism 240...Input buffer memory, 242...Storage unit, 244...Processing head position detection unit, 246...Base position detection unit, 248...Control unit

Claims

1. A first laser array element in which multiple first photonic crystal lasers are arranged in a first direction, A second laser array element in which multiple second photonic crystal lasers are arranged in the first direction, It has, The first laser array element and the second laser array element are moved relative to the workpiece in a second direction intersecting the first direction, and irradiate the workpiece with laser light in a third direction intersecting the first and second directions. The first end photonic crystal laser among the plurality of first photonic crystal lasers is located in the direction most opposite to the first direction among the plurality of first photonic crystal lasers, The second end photonic crystal laser among the plurality of first photonic crystal lasers is the one located most in the first direction among the plurality of first photonic crystal lasers, The first intermediate photonic crystal laser among the plurality of first photonic crystal lasers is located between the first end photonic crystal laser and the second end photonic crystal laser. The third-end photonic crystal laser among the plurality of second photonic crystal lasers is located in the opposite direction to the plurality of second photonic crystal lasers. The fourth-end photonic crystal laser among the plurality of second photonic crystal lasers is the one located most in the first direction among the plurality of second photonic crystal lasers. The second intermediate photonic crystal laser among the plurality of second photonic crystal lasers is located between the third-end photonic crystal laser and the fourth-end photonic crystal laser. Viewed from the second direction, the second end photonic crystal laser and the second intermediate photonic crystal laser overlap. Each of the plurality of first photonic crystal lasers is provided with a plurality of apertures that exhibit a photonic crystal effect. The diameter of the aperture provided in the second end photonic crystal laser is the diameter of the first intermediate A processing head having a diameter larger than the diameter of the aperture provided in the photonic crystal laser.

2. In claim 1, A processing head in which, when viewed from the second direction, the third end photonic crystal laser and the first intermediate photonic crystal laser overlap.

3. In claim 1 or 2, The third laser array element has multiple third photonic crystal lasers arranged in the first direction, The third laser array element moves relative to the workpiece in the second direction while irradiating the workpiece with laser light in the third direction. The fifth-end photonic crystal laser among the plurality of third photonic crystal lasers is located in the opposite direction to the plurality of third photonic crystal lasers. The sixth-end photonic crystal laser among the plurality of third photonic crystal lasers is the one located most in the first direction among the plurality of third photonic crystal lasers. The third intermediate photonic crystal laser among the plurality of third photonic crystal lasers is located between the fifth-end photonic crystal laser and the sixth-end photonic crystal laser. A processing head in which, when viewed from the second direction, the fourth end photonic crystal laser and the third intermediate photonic crystal laser overlap.

4. In claim 3, A processing head in which, when viewed from the second direction, the fifth end photonic crystal laser and the second intermediate photonic crystal laser overlap.

5. In claim 3 or 4, The processing head comprises the first laser array element and the third laser array element, which are arranged in the first direction.

6. In any one of claims 1 to 5, The plurality of first photonic crystal lasers are arranged in a first pitch, The plurality of second photonic crystal lasers are arranged in the first pitch in the processing head.

7. In claim 6, A processing head in which, when viewed from the second direction, the center of the second end photonic crystal laser and the center of the second intermediate photonic crystal laser overlap.

8. A laser processing apparatus having a processing head according to any one of claims 1 to 7.

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