Processing head and laser processing device

Abstract

A machining head and a laser machining device capable of machining a machining target with high precision. A machining head has a first laser array element in which a plurality of first photonic crystal lasers are arranged in a first direction, and a second laser array element in which a plurality of second photonic crystal lasers are arranged in the first direction, the first laser array element and the second laser array element relatively moving with respect to a machining target in a second direction intersecting the first direction, and irradiating laser light toward the machining target in a third direction intersecting the first direction and the second direction, from the second direction, a second end photonic crystal laser and a second intermediate photonic crystal laser overlap.

Description

Technical Field

[0001] This invention relates to processing heads and laser processing apparatus. Background Technology

[0002] Photonic crystal surface-emitting lasers (PCSELs) that utilize the photonic crystal effect are known. PCSELs are used, for example, in the processing head of a laser processing apparatus that irradiates the workpiece with a laser.

[0003] For example, Patent Document 1 describes a laser module having multiple PCSELs. The PCSEL has a substrate and a photonic crystal layer stacked on the substrate. The photonic crystal layer is fabricated by etching a slab layer to form holes.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2018-56148 Summary of the Invention

[0005] In processing heads with multiple PCSELs as described above, the oscillation wavelength of PCSELs located at the periphery of the substrate is often shifted, making it difficult to achieve the desired characteristics. For example, when the substrate with the photonic crystal layer is warped, the etching amount at the periphery is larger than that at the center of the substrate layer, making it impossible to form holes of the desired diameter. Therefore, PCSELs with the desired characteristics cannot be formed at the periphery. If PCSELs with the desired characteristics cannot be formed, the processing accuracy of the processing head decreases.

[0006] Methods for solving problems

[0007] One embodiment of the processing head of the present invention includes: a first laser array element having a plurality of first photonic crystal lasers arranged in a first direction; and a second laser array element having a plurality of second photonic crystal lasers arranged in the first direction. The first and second laser array elements move relative to a workpiece in a second direction intersecting the first direction while irradiating the workpiece with laser light in a third direction intersecting both the first and second directions. A first-end photonic crystal laser among the plurality of first photonic crystal lasers is located at a position closest to the direction opposite to the first direction, and a second-end photonic crystal laser among the plurality of first photonic crystal lasers is located at a position relative to the first photonic crystal lasers in the direction opposite to the first direction. 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 at the position closest to the opposite direction among the plurality of second photonic crystal lasers. The fourth end photonic crystal laser among the plurality of second photonic crystal lasers is located at the position closest to 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. When viewed from the second direction, the second end photonic crystal laser and the second intermediate photonic crystal laser overlap.

[0008] One embodiment of the laser processing apparatus of the present invention includes the processing head. Attached Figure Description

[0009] Figure 1 This is a schematic top view of the processing head according to the first embodiment.

[0010] Figure 2 This is a top view schematically showing the first photonic crystal laser of the processing head according to the first embodiment.

[0011] Figure 3 This is a schematic cross-sectional view of the first photonic crystal laser of the processing head according to the first embodiment.

[0012] Figure 4 This is a cross-sectional view schematically illustrating the manufacturing process of the processing head according to the first embodiment.

[0013] Figure 5 This is a cross-sectional view schematically illustrating the manufacturing process of the processing head according to the first embodiment.

[0014] Figure 6This is a cross-sectional view schematically illustrating the manufacturing process of the processing head according to the first embodiment.

[0015] Figure 7 This is a cross-sectional view schematically illustrating the manufacturing process of the processing head according to the first embodiment.

[0016] Figure 8 This is a top view schematically showing a processing head of a first variant of the first embodiment.

[0017] Figure 9 This is a top view schematically showing a second variation of the processing head of the first embodiment.

[0018] Figure 10 This is a top view schematically showing the first photonic crystal laser of the processing head in a second variation of the first embodiment.

[0019] Figure 11 This is a perspective view schematically showing the laser processing apparatus of the second embodiment.

[0020] Figure 12 This is a functional block diagram of the laser processing apparatus according to the second embodiment.

[0021] Label Explanation

[0022] 2: Resist layer; 4: Opening; 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: Fourth PCSEL; 34a: Seventh end PCSEL SEL; 34b: Eighth PCSEL; 34c: Fourth intermediate PCSEL; 35: Fifth PCSEL; 35a: Ninth PCSEL; 35b: Tenth PCSEL; 35c: Fifth intermediate PCSEL; 41: DBR layer; 42: First semiconductor layer; 43: First guiding layer; 44: Quantum well layer; 45: Second guiding layer; 46: Second semiconductor layer; 47: Substrate; 50: First electrode; 52: Second electrode; 54: Through hole; 60: Opening; 100, 110, 120: Processing head; 200: Laser processing device; 210: Moving mechanism; 220: Condensing lens; 230: Worktable; 232: Base; 234: Lifting mechanism; 240: Input buffer memory; 242: Storage unit; 244: Processing head position detection unit; 246: Base position detection unit; 248: Control unit. Detailed Implementation

[0023] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Furthermore, the embodiments described below do not unduly limit the scope of the invention as defined in the claims. Additionally, not all structures described below are necessarily essential structural elements of the present invention.

[0024] 1. First Implementation Method

[0025] 1.1. Processing head

[0026] First, the processing head of the first embodiment will be described with reference to the accompanying drawings. Figure 1 This is a schematic top view of the processing head 100 according to the first embodiment. Furthermore, in Figure 1 In the diagram, the X-axis, Y-axis, and Z-axis are shown as three mutually perpendicular axes.

[0027] like Figure 1 As shown, the processing head 100 has, for example, a substrate 10 and a laser array element 20.

[0028] The substrate 10 supports the laser array element 20. The material of the substrate 10 is not particularly limited.

[0029] Laser array element 20 is disposed on substrate 10. Laser array element 20 is, for example, bonded to substrate 10. In the illustrated example, the planar shape of laser array element 20 is a rectangle with a long side parallel to the X-axis.

[0030] The laser array element 20 moves relative to a workpiece (not shown) in a second direction intersecting the first direction. The laser array element 20 can be moved while the workpiece is fixed, or the workpiece can be moved while the laser array element 20 is fixed. The laser array element 20 moves, for example, together with the substrate 10. The laser array element 20 and the substrate 10 are moved by a moving mechanism (not shown).

[0031] The laser array element 20 moves relative to the workpiece while irradiating the workpiece with a laser along a third direction that intersects the first and second directions. The first, second, and third directions are, for example, mutually perpendicular directions. 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.

[0032] 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.

[0033] The first laser array element 20a, the third laser array element 20c, and the fifth laser array element 20e are arranged along the +X axis. The third laser array element 20c is disposed 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 disposed along the +X axis of the first laser array element 20a. For example, the distance between the first laser array element 20a and the third laser array element 20c is equal to the distance between the third laser array element 20c and the fifth laser array element 20e.

[0034] The second laser array element 20b and the fourth laser array element 20d are arranged along the +X axis. In the illustrated example, the fourth laser array element 20d is positioned along the +X axis of the second laser array element 20b. For example, the distance between the second laser array element 20b and the fourth laser array element 20d is equal to the distance between the first laser array element 20a and the third laser array element 20c.

[0035] The second laser array element 20b is positioned along the -Y axis of laser array elements 20a and 20c. The fourth laser array element 20d is positioned along the -Y axis of laser array elements 20c and 20e.

[0036] 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. Photonic crystal lasers 31, 32, 33, 34, and 35 are PCSELs. Hereinafter, "photonic crystal laser" will also be referred to as "PCSEL".

[0037] The planar shape of PCSEL31, 32, 33, 34, and 35 is, for example, a square. When viewed from the Z-axis direction, the sizes of PCSEL31, 32, 33, 34, and 35 are, for example, the same.

[0038] There can be multiple first PCSEL31s. There is no particular limit to the number of first PCSEL31s, as long as there are three or more. In the example shown, there are five first PCSEL31s. Similarly, there are multiple PCSELs 32, 33, 34, and 35.

[0039] Multiple first PCSEL31s are arranged with a first spacing P in the X-axis direction. The multiple first PCSEL31s are arranged in a straight line. Furthermore, the "first spacing P" refers to the distance between the centers of adjacent first PCSEL31s in the X-axis direction. When the planar shape of a first PCSEL31 is circular, the "center of the first PCSEL31" is the center of that circle; when the planar shape of a first PCSEL31 is not circular, the "center of the first PCSEL31" is the center of the smallest containing circle. For example, when the planar shape of a first PCSEL31 is polygonal, the center of the first PCSEL31 is the center of the smallest circle containing that polygon; when the planar shape of a first PCSEL31 is elliptical, the center of the first PCSEL31 is the center of the smallest circle containing that ellipse.

[0040] Similarly, multiple second PCSEL 32, multiple third PCSEL 33, multiple fourth PCSEL 34, and multiple fifth PCSEL 35 are arranged at a first spacing P in the X-axis direction. The multiple second PCSEL 32 are arranged in a straight line. The multiple third PCSEL 33 are arranged in a straight line. The multiple fourth PCSEL 34 are arranged in a straight line. The multiple fifth PCSEL 35 are arranged in a straight line.

[0041] The first end PCSEL31a of the plurality of first PCSEL31 is located at the position closest to the -X-axis among the plurality of first PCSEL31. The second end PCSEL31b of the plurality of first PCSEL31 is located at the position closest to the +X-axis among the plurality of first PCSEL31. The first intermediate PCSEL31c of the plurality of first PCSEL31 is located between the first end PCSEL31a and the second end PCSEL31b. In the illustrated example, there are 3 first intermediate PCSEL31c.

[0042] The third PCSEL32a among the multiple second PCSEL32s is located closest to the -X-axis position among the multiple second PCSEL32s. The fourth PCSEL32b among the multiple second PCSEL32s is located closest to the +X-axis position among the multiple second PCSEL32s. The second intermediate PCSEL32c among the multiple second PCSEL32s is located between the third PCSEL32a and the fourth PCSEL32b. In the illustrated example, there are 3 second intermediate PCSEL32cs.

[0043] The fifth PCSEL 33a among the multiple third PCSELs 33 is located closest to the -X-axis position. The sixth PCSEL 33b among the multiple third PCSELs 33 is located closest to the +X-axis position. The third intermediate PCSEL 33c among the multiple third PCSELs 33 is located between the fifth PCSEL 33a and the sixth PCSEL 33b. In the illustrated example, there are three third intermediate PCSELs 33c.

[0044] The seventh PCSEL34a among the multiple fourth PCSEL34s is located closest to the -X-axis position. The eighth PCSEL34b among the multiple fourth PCSEL34s is located closest to the +X-axis position. The fourth intermediate PCSEL34c among the multiple fourth PCSEL34s is located between the seventh PCSEL34a and the eighth PCSEL34b. In the illustrated example, there are three fourth intermediate PCSEL34cs.

[0045] The ninth PCSEL 35a among the multiple fifth PCSEL 35s is located closest to the -X-axis position among the multiple fifth PCSEL 35s. The tenth PCSEL 35b among the multiple fifth PCSEL 35s is located closest to the +X-axis position among the multiple fifth PCSEL 35s. The fifth intermediate PCSEL 35c among the multiple fifth PCSEL 35s is located between the ninth PCSEL 35a and the tenth PCSEL 35b. In the illustrated example, there are 3 fifth intermediate PCSEL 35cs.

[0046] Viewed from the +Y axis direction, the second end PCSEL31b overlaps with the second intermediate PCSEL32c. In the illustrated example, the second end PCSEL31b overlaps with the second intermediate PCSEL32c closest to the -X axis direction among the multiple second intermediate PCSEL32cs.

[0047] Viewed from the +Y axis direction, the third end PCSEL32a overlaps with the first intermediate PCSEL31c. In the illustrated example, the third end PCSEL32a overlaps with the first intermediate PCSEL31c closest to the +X axis direction among the multiple first intermediate PCSEL31cs.

[0048] Viewed from the +Y axis direction, the fourth end PCSEL32b overlaps with the third intermediate PCSEL33c. In the illustrated example, the fourth end PCSEL32b overlaps with the third intermediate PCSEL33c closest to the -X axis direction among the multiple third intermediate PCSEL33cs.

[0049] Viewed from the +Y axis direction, the fifth end PCSEL33a overlaps with the second intermediate PCSEL32c. In the illustrated example, the fifth end PCSEL33a overlaps with the second intermediate PCSEL32c closest to the +X axis direction among the multiple second intermediate PCSEL32cs.

[0050] Viewed from the +Y axis direction, the sixth end PCSEL33b overlaps with the fourth intermediate PCSEL34c. In the illustrated example, the sixth end PCSEL33b overlaps with the fourth intermediate PCSEL34c closest to the -X axis direction among the multiple fourth intermediate PCSEL34cs.

[0051] Viewed from the +Y axis direction, the seventh end PCSEL34a overlaps with the third intermediate PCSEL33c. In the illustrated example, the seventh end PCSEL34a overlaps with the third intermediate PCSEL33c closest to the +X axis direction among the multiple third intermediate PCSEL33cs.

[0052] Viewed from the +Y axis direction, the eighth PCSEL34b overlaps with the fifth intermediate PCSEL35c. In the illustrated example, the eighth PCSEL34b overlaps with the fifth intermediate PCSEL35c closest to the -X axis direction among the multiple fifth intermediate PCSEL35cs.

[0053] Viewed from the +Y axis direction, the ninth end PCSEL35a overlaps with the fourth intermediate PCSEL34c. In the illustrated example, the ninth end PCSEL35a overlaps with the fourth intermediate PCSEL34c that is closest to the +X axis direction among the multiple fourth intermediate PCSEL34cs.

[0054] Viewed from the Y-axis, the center α of the second PCSEL 31b overlaps with the center β of the second intermediate PCSEL 32c. Thus, when viewed from the Y-axis, the center of one PCSEL overlaps with the center of the other PCSEL.

[0055] End PCSELs 31a, 31b, 32a, 32b, 33a, 33b, 34a, 34b, 35a, and 35b are not driven. Middle PCSELs 31c, 32c, 33c, 34c, and 35c are driven.

[0056] here, Figure 2 This is a schematic top view of a first PCSEL31. Figure 3 This schematically illustrates the edge of a first PCSEL31. Figure 2 A cross-sectional view along line III-III. PCSEL32, 33, 34 and 35 have essentially the same configuration as the first PCSEL31.

[0057] like Figure 2 and Figure 3 As shown, the first PCSEL 31 has, for example, a DBR (Distributed Bragg Reflector) layer 41, a first semiconductor layer 42, a first guiding layer 43, a quantum well layer 44, a second guiding layer 45, a second semiconductor layer 46, a substrate 47, a first electrode 50, and a second electrode 52.

[0058] DBR layer 41 reflects the light generated by quantum well layer 44. In the illustrated example, DBR layer 41 reflects the light generated by quantum well layer 44 in the +Z axis direction.

[0059] like Figure 3 As shown, a first semiconductor layer 42 is disposed on the DBR layer 41. The first semiconductor layer 42 is disposed between the DBR layer 41 and the first conductive layer 43. The first semiconductor layer 42 is a semiconductor layer of a first conductivity type. For example, the first semiconductor layer 42 is a p-type semiconductor layer doped with Mg.

[0060] Furthermore, in "1.1. Processing Head", in the Z-axis direction, with the quantum well layer 44 as the reference, the direction from the quantum well layer 44 toward the second guide layer 45 is defined as "up", and the direction from the quantum well layer 44 toward the first guide layer 43 is defined as "down". In addition, the direction perpendicular to the Z-axis direction is also referred to as the "in-plane direction".

[0061] A first guiding layer 43 is disposed on the first semiconductor layer 42. The first guiding layer 43 is disposed between the first semiconductor layer 42 and the quantum well layer 44. The first guiding layer 43 may have, for example, an SL (Semiconductor Superlattice) structure composed of an undoped i-type GaN layer and an InGaN layer. The number of GaN and InGaN layers constituting the first guiding layer 43 is not particularly limited.

[0062] An opening 60 is provided in the first guide layer 43. The opening 60 is, for example, a hole. Figure 2 In the example shown, the planar shape of the opening 60 is circular. The diameter of the opening 60 is, for example, 50 nm or more and 500 nm or less.

[0063] Furthermore, when the planar shape of the opening 60 is circular, "the diameter of the opening 60" refers to the diameter; when the planar shape of the opening 60 is non-circular, "the diameter of the opening 60" refers to the diameter of the smallest circle that contains the circle. For example, when the planar shape of the opening 60 is polygonal, the diameter of the opening 60 is the diameter of the smallest circle that contains the polygon; when the planar shape of the opening 60 is elliptical, the diameter of the opening 60 is the diameter of the smallest circle that contains the ellipse.

[0064] Multiple openings 60 are provided. The multiple openings 60 are isolated from each other. The spacing between adjacent openings 60 is, for example, 1 nm or more and 500 nm or less. Viewed from the Z-axis direction, the multiple openings 60 are arranged in a predetermined direction at a predetermined spacing. The multiple openings 60 are arranged, for example, in an equilateral triangular lattice or a square lattice. In the illustrated example, the multiple openings 60 are arranged in a square lattice. The multiple openings 60 can exhibit photonic crystal effects.

[0065] Furthermore, "the spacing between openings 60" refers to the distance between the centers of adjacent openings 60 in a specified direction. When the planar shape of an opening 60 is circular, the "center of the opening 60" is the center of that circle; when the planar shape of an opening 60 is non-circular, the "center of the opening 60" is the center of the smallest circle that contains that circle. For example, when the planar shape of an opening 60 is polygonal, the center of the opening 60 is the center of the smallest circle that contains that polygon; when the planar shape of an opening 60 is elliptical, the center of the opening 60 is the center of the smallest circle that contains that ellipse.

[0066] A quantum well layer 44 is disposed on the first guiding layer 43. The quantum well layer 44 is disposed between the first guiding layer 43 and the second guiding layer 45. The quantum well layer 44 generates light by injecting current. The quantum well layer 44 has, for example, a well layer and a blocking layer. The well layer and the blocking layer are undoped type i-type semiconductor layers. The well layer is, for example, an InGaN layer. The blocking layer is, for example, a GaN layer. The quantum well layer 44 has an MQW (Multiple Quantum Well) structure composed of a well layer and a blocking layer.

[0067] Furthermore, there is no particular limitation on the number of well layers and barrier layers constituting quantum well layer 44. For example, only one well layer may be provided, in which case quantum well layer 44 has an SQW (Single Quantum Well) structure.

[0068] The second guiding layer 45 is disposed on the quantum well layer 44. The second guiding layer 45 is located between the quantum well layer 44 and the second semiconductor layer 46. The second guiding layer 45 has, for example, an SL structure composed of an undoped i-type GaN layer and an InGaN layer. The number of GaN and InGaN layers constituting the second guiding layer 45 is not particularly limited. The first guiding layer 43 and the second guiding layer 45 have the function of increasing the optical confinement coefficient of the first PCSEL 31.

[0069] Furthermore, although not shown in the figure, the multiple openings 60 may also be provided on the second guide layer 45 instead of the first guide layer 43.

[0070] The second semiconductor layer 46 is disposed on the second guiding layer 45. The second semiconductor layer 46 is disposed between the second guiding layer 45 and the substrate 47. 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, an n-type GaN layer doped with Si. The first semiconductor layer 42 and the second semiconductor layer 46 are a cladding layer that functions to confine light in the quantum well layer 44.

[0071] In the first PCSEL 31, a pin diode is formed by a p-type first semiconductor layer 42, an intentionally undoped i-type quantum well layer 44, guiding layers 43 and 45, and an n-type second semiconductor layer 46. In the first PCSEL 31, if a forward bias voltage is applied between the first electrode 50 and the second electrode 52, current is injected into the quantum well layer 44, causing electron-hole recombination within the quantum well layer 44. This recombination generates light emission. The light generated in the quantum well layer 44 propagates in the in-plane direction, forming a standing wave through the photonic crystal effect of the multiple openings 60. Gain is received in the quantum well layer 44, resulting in laser oscillation. Furthermore, the first PCSEL 31 emits +1st order diffracted light and -1st order diffracted light as laser light in the Z-axis direction.

[0072] In the first PCSEL 31, the DBR layer 41 can reflect laser light oriented towards the -Z axis direction towards the +Z axis direction. Thus, in the first PCSEL 31, laser light can be emitted in the +Z axis direction.

[0073] Substrate 47 is disposed on the second semiconductor layer 46. Substrate 47 is disposed between the second semiconductor layer 46 and the second electrode 52. Substrate 47 is, for example, an n-type semiconductor substrate doped with Si.

[0074] The first electrode 50 is disposed below the DBR layer 41. The DBR layer 41 may also 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 formed, for example, by sequentially stacking Ni layers and Au layers from the DBR layer 41 side. The first electrode 50 is an electrode used to inject current into the quantum well layer 44.

[0075] The second electrode 52 is disposed on the substrate 47. The substrate 47 may also 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 formed, for example, by sequentially stacking a Cr layer, a Ni layer, and an Au layer from the substrate 47 side. The second electrode 52 is another electrode used to inject current into the quantum well layer 44.

[0076] A through hole 54 is provided in the second electrode 52. The through hole 54 extends through the second electrode 52 along the Z-axis direction. Figure 2 In the example shown, the through-hole 54 is square in shape. Light generated by the quantum well layer 44 is emitted through the through-hole 54.

[0077] For example, among the 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 guiding layer 43 is a common layer, the quantum well layer 44 is a common layer, the second guiding layer 45 is a common layer, the second semiconductor layer 46 is a common layer, and the substrate 47 is a common substrate.

[0078] In the plurality of 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 a separate electrode. Alternatively, the plurality of first electrodes 50 may be continuous with each other, and the plurality of second electrodes 52 may be isolated from each other. In this case, 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 plurality of first PCSELs 31 can be driven individually by the second electrode 52.

[0079] Alternatively, among the plurality of first PCSELs 31 constituting the first laser array element 20a, the first electrode 50 may be an individual electrode, and the second electrode 52 may be a common electrode. Alternatively, among the plurality of first PCSELs 31 constituting the first laser array element 20a, the plurality of first electrodes 50 may be isolated from each other, and the plurality of second electrodes 52 may be continuous with each other. In this case, viewed from the Z-axis direction, the portion overlapping with the first electrode 50 constitutes one first PCSEL 31. The plurality of first PCSELs 31 can be driven individually by the first electrode 50.

[0080] 1.2. Manufacturing method of processing head

[0081] Next, the manufacturing method of the processing head 100 of the first embodiment will be described with reference to the accompanying drawings. Figures 4-7 This is a schematic cross-sectional view illustrating the manufacturing process of the processing head 100 according to the first embodiment. Additionally, for convenience, in Figures 4-7 In, with Figure 3 The diagram is displayed in reverse order.

[0082] like Figure 4 As shown, a second semiconductor layer 46, a second guiding layer 45, a quantum well layer 44, and a first guiding layer 43 are epitaxially grown on substrate 47. Examples of epitaxial growth methods include MOCVD (Metal Organic Chemical Vapor Deposition) and MBE (Molecular Beam Epitaxy).

[0083] In addition, in “1.2. Manufacturing method of processing head”, the direction from quantum well layer 44 toward first guide layer 43 is defined as “up” and the direction from quantum well layer 44 toward second guide layer 45 is defined as “down” for explanation.

[0084] For example, warping occurs on substrate 47 through heating during epitaxial growth and subsequent cooling. In the illustrated example, warping occurs such that the central portion of substrate 47 is positioned higher than the periphery. Along with the warping of substrate 47, the second semiconductor layer 46, the second guiding layer 45, the quantum well layer 44, and the first guiding layer 43 also warp. Additionally, for convenience, in Figure 3 The warping of substrate 47 is omitted in the text.

[0085] like Figure 5 As shown, a resist layer 2 is applied to the first guiding layer 43. The resist layer 2 is applied, for example, by spin coating. Due to the warping of the substrate 47, the thickness of the peripheral portion of the resist layer 2 becomes less than the thickness of the central portion. The material of the resist layer 2 is, for example, a photoresist whose properties change due to UV (ultraviolet) radiation.

[0086] like Figure 6 As shown, the photoresist layer 2 is patterned. Patterning is performed, for example, by nanoimprint lithography. Nanoimprint lithography can process large areas simultaneously.

[0087] like Figure 7 As shown, using the resist layer 2 as a mask, the first guiding layer 43 is dry-etched to form a plurality of openings 60 in the first guiding layer 43. As described above, the thickness of the peripheral portion of the resist layer 2 is smaller than the thickness of the central portion of the resist layer 2, therefore, the peripheral portion of the resist layer 2 is removed during dry etching. Consequently, the peripheral portion of the first guiding layer 43 is side-etched, and the diameter D1 of the peripheral openings 60 is larger than the diameter D2 of the central openings 60. Then, the resist layer 2 is removed using a known method.

[0088] like Figure 7 As shown, after forming the opening 60, the first guiding layer 43 is further epitaxially grown. This closes the opening 60. Examples of epitaxial growth methods include MOCVD and MBE.

[0089] Next, a first semiconductor layer 42 and a DBR layer 41 are epitaxially grown sequentially on the first guiding layer 43. Examples of epitaxial growth methods include MOCVD and MBE.

[0090] 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 evaporation. Furthermore, the formation order of the first electrode 50 and the second electrode 52 is not particularly limited.

[0091] Next, a pattern is formed on the second electrode 52 to form a through-hole 54. Patterning is performed, for example, by photolithography and etching.

[0092] Through the above processes, a first laser array element 20a having a plurality of first PCSEL31s with substrate 47 as a common substrate can be formed.

[0093] By repeating the above steps, a second laser array element 20b having a plurality of second PCSEL32, a third laser array element 20c having a plurality of third PCSEL33, a fourth laser array element 20d having a plurality of fourth PCSEL34, and a fifth laser array element 20e having a plurality of fifth PCSEL35 can be formed.

[0094] Next, 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 using solder (not shown).

[0095] Through the above processes, processing head 100 can be manufactured.

[0096] 1.3. Effects

[0097] The processing head 100 includes a first laser array element 20a having a plurality of first PCSELs 31 arranged in the +X axis direction and a second laser array element 20b having a plurality of second PCSELs 32 arranged in the +X axis direction. The first laser array element 20a and the second laser array element 20b move relative to the workpiece in the +Y axis direction while irradiating the workpiece with laser light in the +Z axis direction. Viewed from the +Y axis direction, the second end PCSEL 31b overlaps with the second intermediate PCSEL 32c.

[0098] Here, the second end PCSEL31b is located further out than the first intermediate PCSEL31c, therefore, as described above, the diameter of the opening 60 is larger than the desired value. Consequently, in the second end PCSEL31b, the oscillation wavelength, oscillation threshold, light intensity, etc., deviate from the desired values.

[0099] As described above, in the processing head 100, when viewed from the +Y axis direction, the second end PCSEL 31b overlaps with the second intermediate PCSEL 32c. Therefore, laser light is not irradiated from the second end PCSEL 31b, but from the second intermediate PCSEL 32c, which overlaps with the second end PCSEL 31b when viewed from the +Y axis direction. This allows laser processing to be performed on the area traversed by the second end PCSEL 31b of the workpiece. Therefore, the processing head 100 can process the workpiece with high precision.

[0100] In the processing head 100, when viewed from the +Y axis direction, the third end PCSEL32a overlaps with the first intermediate PCSEL31c. Therefore, in the processing head 100, laser is not irradiated from the third end PCSEL32a, but from the first intermediate PCSEL31c, which overlaps with the third end PCSEL32a when viewed from the +Y axis direction. This allows laser processing to be performed on the area traversed by the third end PCSEL32a of the workpiece.

[0101] In the processing head 100, a plurality of third PCSELs 33 have third laser array elements 20c arranged in the +X axis direction. The third laser array elements 20c move relative to the workpiece in the +Y axis direction while irradiating laser light toward the workpiece in the +Z axis direction. Viewed from the +Y axis direction, the fourth end PCSEL 32b overlaps with the third intermediate PCSEL 33c. Therefore, in the processing head 100, laser light is not irradiated from the fourth end PCSEL 32b, but from the third intermediate PCSEL 33c, which overlaps with the fourth end PCSEL 32b when viewed from the +Y axis direction. This allows laser processing of the area traversed by the fourth end PCSEL 32b of the workpiece. Furthermore, by providing the third laser array elements 20c, the processing area of ​​the workpiece and the production speed can be increased.

[0102] In the processing head 100, when viewed from the +Y axis direction, the fifth end PCSEL33a overlaps with the second intermediate PCSEL32c. Therefore, in the processing head 100, the laser is not irradiated from the fifth end PCSEL33a, but from the second intermediate PCSEL32c, which overlaps with the fifth end PCSEL33a when viewed from the +Y axis direction. This allows laser processing to be performed on the area traversed by the fifth end PCSEL33a of the workpiece.

[0103] In the machining head 100, the first PCSEL 31 and the third PCSEL 33 are arranged in the +X axis direction. Therefore, compared with the case where the first PCSEL and the third PCSEL are not arranged in the +X axis direction, the size of the machining head 100 in the +Y axis direction can be reduced.

[0104] In the processing head 100, a plurality of first PCSEL 31 are arranged at a first spacing P, and a plurality of second PCSEL 32 are configured at a first spacing P. Therefore, in the processing head 100, the workpiece can be irradiated with laser at equal intervals.

[0105] In the processing head 100, when viewed from the +Y axis direction, the center α of the second end PCSEL31b overlaps with the center β of the second intermediate PCSEL32c. Therefore, in the processing head 100, the workpiece can be irradiated with laser at equal intervals more reliably.

[0106] Furthermore, as described above, an example of manifesting a photonic crystal effect by forming multiple openings 60 in the first guiding layer 43 has been explained, but the photonic crystal effect can also be manifested by forming multiple columnar portions. The multiple columnar portions are formed by epitaxial growth using a mask layer (not shown) as a mask. Compared to the central columnar portions, the peripheral columnar portions of the multiple columnar portions are over-supplied with gas for growth, making abnormal growth more likely. Therefore, even when the photonic crystal effect is manifested by forming multiple columnar portions, the oscillation wavelength, oscillation threshold, light intensity, etc., in the second-end PCSEL 31b are prone to deviating from the desired values. Therefore, even in such cases, by overlapping the second-end PCSEL 31b with the second intermediate PCSEL 32c when viewed from the +Y axis direction, the workpiece can be processed with high precision.

[0107] 1.4. Examples of deformation of the machining head

[0108] 1.4.1. First Variation Example

[0109] Next, the processing head of the first modified example of the first embodiment will be described with reference to the accompanying drawings. Figure 8 This is a top view schematically showing a first modified example of the first embodiment of the processing head 110.

[0110] Hereinafter, in the processing head 110 according to the first variation of the first embodiment, components having the same functions as the constituent components of the processing head 100 of the first embodiment described above will be labeled with the same reference numerals, and detailed descriptions thereof will be omitted. This is the same in the processing head of the second variation of the first embodiment described later.

[0111] In the aforementioned processing head 100, such as Figure 1 As shown, when viewed from the +Y axis direction, the first intermediate PCSEL31c of the first laser array element 20a does not overlap with the second intermediate PCSEL32c of the second laser array element 20b.

[0112] In contrast, in the processing head 110, such as Figure 8As shown, viewed from the +Y axis direction, the first intermediate PCSEL31c and the second intermediate PCSEL32c overlap. In the example shown, there are 7 first intermediate PCSEL31cs and 7 second intermediate PCSEL32cs.

[0113] In the illustrated example, viewed from the +Y axis direction, the first intermediate PCSEL31c1 closest to the +X axis direction among the multiple first intermediate PCSEL31c overlaps with the second second intermediate PCSEL32c2 closest to the -X axis direction among the multiple second intermediate PCSEL32c.

[0114] Viewed from the +Y axis direction, the second first intermediate PCSEL31c2, located near the +X axis, overlaps with the second second intermediate PCSEL32c1, located near the -X axis, among the multiple second intermediate PCSEL32cs. Intermediate PCSELs 31c1 and 32c1 are not driven.

[0115] In the processing head 110, instead of irradiating the first intermediate PCSEL 31c1, the laser is irradiated from the second intermediate PCSEL 32c2, which overlaps with the first intermediate PCSEL 31c1 when viewed from the Y-axis direction. This allows laser processing to be performed on the area through which the first intermediate PCSEL 31c1 passes. Furthermore, instead of irradiating the second intermediate PCSEL 32c1, the laser is irradiated from the first intermediate PCSEL 31c2, which overlaps with the second intermediate PCSEL 32c1 when viewed from the Y-axis direction. This allows laser processing to be performed on the area through which the second intermediate PCSEL 32c1 passes.

[0116] 1.4.2. Second variation

[0117] Next, the processing head of the second variation of the first embodiment will be described with reference to the accompanying drawings. Figure 9 This is a top view schematically showing a second variation of the processing head 120 of the first embodiment. Figure 10 This is a top view schematically showing the first PCSEL31 of the processing head 120 of the second variation of the first embodiment.

[0118] In the aforementioned processing head 100, such as Figure 1 and Figure 2 As shown, the first PCSEL31 has a square planar shape.

[0119] On the other hand, in the processing head 120, such as Figure 9 and Figure 10 As shown, the planar shape of the first PCSEL31 is circular. Similarly, the planar shapes of PCSELs32, 33, 34, and 35 are also circular.

[0120] 2. Second Implementation Method

[0121] Next, the laser processing apparatus of the second embodiment will be described with reference to the accompanying drawings. Figure 11 This is a perspective view schematically showing the laser processing apparatus 200 of the second embodiment. Figure 12 This is a functional block diagram of the laser processing apparatus 200 according to the second embodiment.

[0122] Laser processing equipment 200 is, for example, a metal 3D printer utilizing Selective Laser Melting (SLM). Figure 11 and Figure 12 As shown, the laser processing apparatus 200 includes, for example, a processing head 100, a moving mechanism 210, a focusing lens 220, a worktable 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.

[0123] like Figure 11 As shown, the moving mechanism 210 supports the machining head 100. 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 extending along the Y-axis direction. The moving mechanism 210 is configured, for example, to include a motor (not shown).

[0124] The condenser lens 220 focuses the laser light emitted from the processing head 100. In the illustrated example, the condenser lens 220 is located in the +Z axis direction of the processing head 100. The condenser lens 220 moves in the Y axis direction as the processing head 100 moves. The condenser lens 220 is supported, for example, by a moving mechanism not shown.

[0125] The worktable 230, for example, has a base 232 and a lifting mechanism 234. Metal particles G, which are the workpieces, are supplied to the base 232. The metal particles G are irradiated with a laser emitted from a condenser lens 220. The lifting mechanism 234 moves the base 232 in the Z-axis direction.

[0126] The input buffer memory 240 receives data related to the laser irradiation of the processing head 100, i.e., pattern drawing data, from an external information processing device not shown in the figure. For example... Figure 12 As shown, 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, for example, composed of RAM (Random Access Memory) or ROM (Read Only Memory).

[0127] 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, for example, composed of a linear encoder, a laser length measuring device, etc.

[0128] The control unit 248 controls the moving mechanism 210 and the lifting mechanism 234 based on the detection signals from the processing head position detection unit 244 and the base position detection unit 246. Furthermore, the control unit 248 reads the drawing pattern data stored in the storage unit 242 and controls the processing head 100 based on the read drawing pattern data. The control unit 248 is, for example, composed of a CPU (Central Processing Unit) and dedicated circuitry.

[0129] In the laser processing apparatus 200, firstly, metal particles G, which are 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 simultaneously controls the processing head 100 to perform laser irradiation on the metal particles G, which are the first layer, based on drawn pattern data. The laser-irradiated portion of the metal particles G is melted and solidified.

[0130] Next, the control unit 248 controls the moving mechanism 210 to move the processing head 100 in the -Y axis direction, so that the processing head 100 returns to the initial position, and controls the lifting mechanism 234 of the worktable 230 to perform a movement process that moves the base 232 one layer in the +Z axis direction.

[0131] Then, the control unit 248 repeatedly performs the above-mentioned irradiation and movement processes based on the drawn pattern data until it is determined that all layers of the object to be processed have been formed.

[0132] After determining that all layers of the object to be processed have been formed, the unmelted and unsolidified portions of the metal particles G are removed, for example, by means of blowing air.

[0133] Through the above methods, it is possible to shape the processed object into the desired form.

[0134] The laser processing apparatus 200 includes a processing head 100. Therefore, deviations in the melting degree of the metal particles G can be reduced.

[0135] Unlike the case of using a fiber laser, the laser processing apparatus 200 does not require a galvanometer scanner and an fθ lens, thus enabling miniaturization and cost reduction.

[0136] Furthermore, the laser processing apparatus of the present invention is not limited to metal 3D printers. For example, the laser processing apparatus of the present invention can also be a laser cleaner that uses a laser to remove rust or other deposits attached to metal. Moreover, the laser processing apparatus of the present invention can also be a laser annealing apparatus that uses a laser to heat the surface of metal or resin.

[0137] The above-described embodiments and modifications are examples only and are not limited thereto. For example, the embodiments and modifications can also be appropriately combined.

[0138] This invention includes structures that are substantially the same as those described in the embodiments, such as structures with the same function, method, and result, or structures with the same purpose and effect. Furthermore, this invention includes structures in which non-essential parts of the structures described in the embodiments have been replaced. Additionally, this invention includes structures that achieve the same effect as those described in the embodiments or that can achieve the same purpose. Furthermore, this invention includes structures in which known techniques have been added to the structures described in the embodiments.

[0139] The following content is derived based on the above implementation methods and variations.

[0140] One configuration of the processing head includes: a first laser array element having a plurality of first photonic crystal lasers arranged in a first direction; and a second laser array element having a plurality of second photonic crystal lasers arranged in the first direction. The first and second laser array elements move relative to a workpiece in a second direction intersecting the first direction while irradiating the workpiece with laser light in a third direction intersecting both the first and second directions. A first-end photonic crystal laser among the plurality of first photonic crystal lasers is located closest to the direction opposite to the first direction, and a second-end photonic crystal laser among the plurality of first photonic crystal lasers is located at the position of 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 at the position closest to the opposite direction among the plurality of second photonic crystal lasers. The fourth end photonic crystal laser among the plurality of second photonic crystal lasers is located at the position closest to 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. When viewed from the second direction, the second end photonic crystal laser and the second intermediate photonic crystal laser overlap.

[0141] This processing head enables the processing of objects with high precision.

[0142] In one configuration of the processing head, when viewed from the second direction, the third-end photonic crystal laser may also overlap with the first intermediate photonic crystal laser.

[0143] According to this processing head, laser irradiation is performed on the area through which the third-end photonic crystal laser of the object being processed is passed by the first intermediate photonic crystal laser that overlaps with the third-end photonic crystal laser when viewed from the second direction.

[0144] In one embodiment of the processing head, it may also be: a third laser array element having a plurality of third photonic crystal lasers arranged in the first direction, the third laser array element irradiating the object being processed along the third third direction while moving relative to the object being processed in the second direction, wherein the fifth end photonic crystal laser of the plurality of third photonic crystal lasers is located at the position closest to the opposite direction among the plurality of third photonic crystal lasers, the sixth end photonic crystal laser of the plurality of third photonic crystal lasers is located at the position closest to the first direction among the plurality of third photonic crystal lasers, the third intermediate photonic crystal laser of the plurality of third photonic crystal lasers is located between the fifth end photonic crystal laser and the sixth end photonic crystal laser, and the fourth end photonic crystal laser overlaps with the third intermediate photonic crystal laser when viewed from the second direction.

[0145] According to this processing head, by irradiating the object with a laser from a third intermediate photonic crystal laser that overlaps with the fourth-end photonic crystal laser when viewed from the second direction, laser processing can be performed on the area through which the fourth-end photonic crystal laser passes.

[0146] In one configuration of the processing head, when viewed from the second direction, the fifth end photonic crystal laser and the second intermediate photonic crystal laser may also overlap.

[0147] According to this processing head, by irradiating the area through which the fifth-end photonic crystal laser of the object is traversed by a second intermediate photonic crystal laser that overlaps with the fifth-end photonic crystal laser when viewed from the second direction, laser processing can be performed on the object being processed.

[0148] In one configuration of the processing head, the first laser array element and the third laser array element may be arranged in the first direction.

[0149] Based on this processing head, the size in the second direction can be reduced.

[0150] In one embodiment of the processing head, the plurality of first photonic crystal lasers may be arranged at a first spacing, and the plurality of second photonic crystal lasers may be configured at the first spacing.

[0151] This processing head can irradiate the workpiece with laser at equal intervals.

[0152] In one configuration of the processing head, the center of the second end photonic crystal laser may overlap with the center of the second intermediate photonic crystal laser when viewed from the second direction.

[0153] This processing head allows for more reliable laser irradiation of the workpiece at equal intervals.

[0154] One method of laser processing apparatus has the processing head.

Claims

1. A processing head, The processing head has: A first laser array element, wherein a plurality of first photonic crystal lasers are arranged in a first direction; and The second laser array element has multiple second photonic crystal lasers arranged in the first direction. The first laser array element and the second laser array element move relative to the workpiece in a second direction intersecting the first direction, while simultaneously irradiating the workpiece with laser light in a third direction intersecting both the first and second directions. The first end photonic crystal laser among the plurality of first photonic crystal lasers is located in the position closest to the direction 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 located at the position closest to 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 position closest to the direction opposite to the first direction among the plurality of second photonic crystal lasers. The fourth end photonic crystal laser among the plurality of second photonic crystal lasers is located at the position closest to 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 overlaps with the second intermediate photonic crystal laser.

2. The processing head according to claim 1, wherein, Viewed from the second direction, the third-end photonic crystal laser overlaps with the first intermediate photonic crystal laser.

3. The processing head according to claim 1 or 2, wherein, The processing head has a third laser array element, which 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 along the third direction. The fifth-end photonic crystal laser among the plurality of third photonic crystal lasers is located in the position closest to the direction opposite to the first direction among the plurality of third photonic crystal lasers. The sixth-end photonic crystal laser among the plurality of third photonic crystal lasers is located at the position closest to 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. Viewed from the second direction, the fourth end photonic crystal laser overlaps with the third intermediate photonic crystal laser.

4. The processing head according to claim 3, wherein, Viewed from the second direction, the fifth end photonic crystal laser overlaps with the second intermediate photonic crystal laser.

5. The processing head according to claim 3, wherein, The first laser array element and the third laser array element are arranged in the first direction.

6. The processing head according to claim 1 or 2, wherein, The plurality of first photonic crystal lasers are arranged at a first spacing. The plurality of second photonic crystal lasers are configured with the first spacing.

7. The processing head according to claim 6, wherein, Viewed from the second direction, the center of the second end photonic crystal laser overlaps with the center of the second intermediate photonic crystal laser.

8. A laser processing apparatus having a processing head as described in any one of claims 1-7.

Images