JP7089504B2 - Semiconductor light emitting device and its manufacturing method - Google Patents

Description

The present invention relates to a semiconductor light emitting device and a method for manufacturing the same.

The semiconductor light emitting device described in Patent Document 1 includes an active layer and a phase modulation layer optically coupled to the active layer. The phase modulation layer has a basic layer and a plurality of different refractive index regions arranged in the basic layer. The semiconductor light emitting device described in Patent Document 1 emits light having a beam pattern (beam projection pattern) corresponding to an arrangement pattern of a plurality of different refractive index regions. That is, the arrangement pattern of the plurality of different refractive index regions is set according to the target beam pattern. Patent Document 1 also describes an application example of such a semiconductor light emitting element. In the above application example, a plurality of semiconductor light emitting devices having different directions of laser beams emitted from each of them are arranged one-dimensionally or two-dimensionally on a support substrate. The application example is configured to scan a laser beam with respect to an object by sequentially lighting a plurality of arranged semiconductor light emitting elements. The above application example is applied to measurement of a distance to an object, laser processing of the object, and the like by scanning a laser beam with respect to the object.

International release WO2016 / 148075

Y. Kurosaka et al., "Effects of non-lasing band in two-dimensional photonic-crystal lasers clarified using omnidirectional band structure," Opt. Express 20, 21773-21783 (2012) K. Sakai et al., “Coupled-Wave Theory for Square-Lattice Photonic Crystal Lasers With TE Polarization,” IEEE J.Q. E. 46, 788-795 (2010) Peng, et al., “Coupled-wave analysis for photonic-crystal surface-emitting lasers on air holes with arbitrary unsubstituteds,” Optics Express Vol. 19, No. 24, pp. 24672-24686 (2011).

As a result of examining the conventional semiconductor light emitting device, the inventors have discovered the following problems. That is, in the application example described in Patent Document 1, a plurality of semiconductor light emitting elements must be arranged on the support substrate with high accuracy. Since it is not easy to do so, it is not easy to realize highly accurate irradiation of light of a desired beam projection pattern onto a desired beam projection region. Further, since a step of arranging a plurality of semiconductor light emitting elements on the support substrate is required, there is a possibility that the manufacturing process may be complicated.

The present invention has been made in view of such a problem, does not require a step of arranging a plurality of semiconductor light emitting elements on a support substrate, and easily irradiates a target beam projection region with light of a target beam projection pattern. It is an object of the present invention to provide a semiconductor light emitting element realized with high accuracy and a method for manufacturing the same.

The semiconductor light emitting element according to the present embodiment is a single semiconductor light emitting element having a plurality of light emitting parts in which crosstalk between adjacent light emitting parts is reduced, and the first surface and the first surface facing the first surface are opposed to each other. A semiconductor light emitting element having two surfaces, one of which functions as a light emitting surface for outputting light and the other functioning as a support surface (including a reflecting surface), and is an active layer. A phase modulation layer including a plurality of phase modulation regions, a first clad layer, a second clad layer, a first surface side electrode, a plurality of second surface side electrodes, and a common substrate layer are provided. The active layer is located between the first and second surfaces. The plurality of phase modulation layers included in the phase modulation layer are optically coupled to each other with the active layer. Each of the plurality of phase modulation regions is arranged so as to reduce the occurrence of crosstalk between adjacent phase modulation regions, and each constitutes a part of an independent light emitting unit. Further, each of the plurality of phase modulation regions includes a basic region having a first refractive index and a plurality of different refractive index regions each provided in the basic region and having a second refractive index different from the first refractive index. include. The first clad layer is located on the side where the first surface is arranged with respect to the laminated structure including at least the active layer and the phase modulation layer. The second clad layer is arranged on the side where the second surface is located with respect to the laminated structure. The first surface side electrode is arranged on the side where the first surface is located with respect to the first clad layer. Each of the plurality of second surface side electrodes corresponds to a plurality of phase modulation regions, and is arranged on the side where the second surface is located with respect to the second clad layer. These plurality of second surface side electrodes are arranged in a plurality of regions that overlap with the plurality of phase modulation regions when viewed along the stacking direction of the laminated structure. The common substrate layer is arranged between the first clad layer and the first surface side electrode, and has a continuous surface holding a plurality of phase modulation regions.

In particular, the plurality of different refractive index regions in each of the plurality of phase modulation regions follow an arrangement pattern in which the center of gravity thereof is located at a position deviated from each grid point in the virtual square grid in the basic region by a predetermined distance. Placed in the basic area. As for the arrangement pattern in each of the plurality of phase modulation regions (arrangement pattern of the plurality of different refractive index regions), the drive current is supplied from the second surface side electrode corresponding to the phase modulation region arranged on the support surface side. The beam projection pattern of the light output from the light emitting surface at that time and the beam projection region which is the projection range of the beam projection pattern are defined to match the target beam projection pattern and the target beam projection region.

The method for manufacturing a semiconductor light emitting element according to the present embodiment manufactures a semiconductor light emitting element having the above-mentioned structure. Specifically, the manufacturing method comprises a first step of forming a common substrate layer, a second step of forming an element body on the common substrate layer, and a third step of forming a separation region in the element body. At least prepare. In the second step, the element main body formed on the common substrate layer has a third surface and a fourth surface facing the third surface and facing the common substrate layer. Further, the element main body includes at least an active layer, a phase modulation layer, a first clad layer, and a second clad layer arranged between the third surface and the fourth surface. At the end of the second step, the basic region in the phase modulation layer is arranged in a state where a plurality of parts (each containing a plurality of different refractive index regions) which should be a plurality of phase modulation regions are separated from each other by a predetermined distance. Consists of a single layer. In the third step, the separation region formed in the element main body electrically separates a plurality of portions that should be at least a plurality of phase modulation regions. Further, the separation region is formed from the third surface to the fourth surface until it reaches the common substrate layer.

According to the present invention, a semiconductor light emitting device and a semiconductor light emitting device in which a step of arranging a plurality of semiconductor light emitting devices on a support substrate is not required, and light of a target beam projection pattern can be easily and accurately irradiated to a target beam projection region. The manufacturing method can be provided.

Is a view of the semiconductor light emitting device according to the first embodiment as viewed from the first surface side. Is a view of the semiconductor light emitting device according to the first embodiment as viewed from the second surface side. Is a cross-sectional view taken along the line III-III of FIGS. 1 and 2. Is a schematic diagram for explaining an arrangement pattern (rotation method) of the different refractive index region in the phase modulation region. Is a diagram for explaining the positional relationship between the center of gravity of the different refractive index region and the grid points in the virtual square grid as an example of the arrangement pattern determined by the rotation method. Is a diagram for explaining the relationship between the target beam projection pattern (optical image) of the light output from the semiconductor light emitting device and the rotation angle distribution in the phase modulation layer. Is a diagram showing an example of a target beam projection pattern in the semiconductor light emitting device according to the first embodiment and a phase distribution among complex amplitude distributions obtained by inverse Fourier transforming the corresponding original pattern. Is a block diagram showing a configuration of a light emitting device including a semiconductor light emitting device according to the first embodiment. Is a view of the semiconductor light emitting element according to the second embodiment as viewed from the first surface side. Is a view of the semiconductor light emitting element according to the second embodiment as viewed from the second surface side. Is a sectional view taken along the line XX of FIGS. 9 and 10. Is a diagram showing an example of a target beam projection pattern in the semiconductor light emitting element according to the second and third embodiments, and a phase distribution among complex amplitude distributions obtained by inverse Fourier transforming the corresponding original pattern. .. Is an example of the target beam projection pattern different from FIG. 12 in the semiconductor light emitting element according to the second and third embodiments, and the phase distribution of the complex amplitude distribution obtained by inverse Fourier transforming the corresponding original pattern. It is a figure which shows. Is a block diagram showing a configuration of a light emitting device including a semiconductor light emitting device according to the second embodiment. Is a view of the semiconductor light emitting device according to the third embodiment as viewed from the first surface side. Is a view of the semiconductor light emitting device according to the third embodiment as viewed from the second surface side. 15 is a cross-sectional view taken along the line XVI-XVI of FIGS. 15 and 16. It is a block diagram which shows the structure of the light emitting device which comprises the semiconductor light emitting element which concerns on 3rd Embodiment. Is a view of the semiconductor light emitting device according to the fourth embodiment as viewed from the first surface side. Is a view of the semiconductor light emitting device according to the fourth embodiment as viewed from the second surface side. Is a sectional view taken along the line XX-XX of FIGS. 19 and 20. Is a figure showing an example (rotational method) of the in-plane shape of the XY in-plane in the different refractive index region, which does not have the rotational symmetry of 180 °. Is a diagram showing a first modification example of the phase modulation region shown in FIG. Is, as another example of the arrangement pattern determined by the rotation method, a different refractive index region (displacement different refractive index) when a lattice point different refractive index region is provided in addition to the different refractive index region (displaced different refractive index region). It is a figure for demonstrating the positional relationship between the center of gravity of a region) and the lattice point different refractive index region. Is an example of a combination of a different refractive index region (displaced different refractive index region) and a lattice point refractive index region when a grid point different refractive index region is provided in addition to the different refractive index region (displaced different refractive index region). It is a figure which shows the method). Is a diagram showing a modified example (rotation method) in which a lattice point different refractive index region is provided in addition to the different refractive index region (displacement different refractive index region). Is a diagram showing a second modification of the phase modulation region shown in FIG. Is a schematic diagram for explaining the arrangement pattern (on-axis shift method) of the different refractive index region in the phase modulation layer. Is a figure for explaining the positional relationship between the center of gravity G1 in the different refractive index region and the lattice point O in the virtual square lattice as an example of the arrangement pattern determined by the axis shift method. Is a plan view showing an example in which the refractive index substantially periodic structure is applied only within a specific region of the phase modulation layer as a first modification of the phase modulation layer of FIG. 28. Is a diagram illustrating points to be noted when determining the arrangement of the different refractive index region by obtaining the phase angle distribution from the inverse Fourier transform result of the target beam projection pattern (light image). Is a diagram showing an example of a beam projection pattern output from a semiconductor light emitting device and a light intensity distribution (graph) in a cross section including an axis intersecting the light emitting surface of the semiconductor light emitting device and perpendicular to the light emitting surface. Is a phase distribution corresponding to the beam projection pattern shown in FIG. 32 (a) and a partially enlarged view thereof. Is a diagram conceptually showing an example of a beam projection pattern of a traveling wave in each direction. In this example, the inclination angle of the straight line L with respect to the X-axis and the Y-axis is 45 °. Is a figure showing a rotation method of rotating a different refractive index region around a grid point and a traveling wave AU, AD, AR, AL as a method of determining an arrangement pattern of the different refractive index region. As a method of determining the arrangement pattern of the different refractive index region, an on-axis shift method of moving the different refractive index region on an axis inclined with respect to a square grid through a grid point and a traveling wave AU, AD, AR, AL It is a figure which shows. Is a figure showing an example (on-axis shift method) of the planar shape of the different refractive index region. Is a diagram showing another example (on-axis shift method) of the planar shape of the different refractive index region. Is a figure showing still another example (on-axis shift method) of the planar shape of the different refractive index region. Is a diagram showing a second modification of the phase modulation layer of FIG. 28. Is a diagram for explaining coordinate conversion from spherical coordinates (d1, θ _tilt , θ _rot ) to coordinates (x, y, z) in the XYZ Cartesian coordinate system.

[Explanation of Embodiments of the present invention]
First, the contents of the embodiments of the present invention will be individually listed and described.

(1) The semiconductor light emitting device according to the present embodiment is, as one embodiment, a single semiconductor light emitting device having a plurality of light emitting parts in which crosstalk between adjacent light emitting parts is reduced, and the first surface thereof. A semiconductor having a second surface facing the first surface, one of which functions as a light emitting surface for outputting light and the other functioning as a support surface (including a reflecting surface). A light emitting element, which includes an active layer, a phase modulation layer including a plurality of phase modulation regions, a first clad layer, a second clad layer, a first surface side electrode, and a plurality of second surface side electrodes. A common substrate layer is provided. The active layer is located between the first and second surfaces. The plurality of phase modulation layers included in the phase modulation layer are optically coupled to each other with the active layer. Each of the plurality of phase modulation regions is arranged so as to reduce the occurrence of crosstalk between adjacent phase modulation regions, and each constitutes a part of an independent light emitting unit. Further, each of the plurality of phase modulation regions includes a basic region having a first refractive index and a plurality of different refractive index regions each provided in the basic region and having a second refractive index different from the first refractive index. include. The first clad layer is located on the side where the first surface is arranged with respect to the laminated structure including at least the active layer and the phase modulation layer. The second clad layer is arranged on the side where the second surface is located with respect to the laminated structure. The first surface side electrode is arranged on the side where the first surface is located with respect to the first clad layer. Each of the plurality of second surface side electrodes corresponds to a plurality of phase modulation regions, and is arranged on the side where the second surface is located with respect to the second clad layer. These plurality of second surface side electrodes are arranged in a plurality of regions that overlap with the plurality of phase modulation regions when viewed along the stacking direction of the laminated structure. The common substrate layer is arranged between the first clad layer and the first surface side electrode, and has a continuous surface holding a plurality of phase modulation regions.

Further, in each of the plurality of phase modulation regions, the plurality of different refractive index regions are output from the light emitting surface when the drive current is supplied from the corresponding second surface side electrode among the plurality of second surface side electrodes. The beam projection pattern of light and the beam projection region which is the projection range of the beam projection pattern are arranged at predetermined positions in the basic region according to the arrangement pattern for matching the target beam projection pattern and the target beam projection region, respectively. ..

As the first precondition, a Z-axis that coincides with the normal direction of the light emitting surface and an X-axis and a Y-axis that coincide with one surface of the phase modulation layer including a plurality of different refractive index regions and are orthogonal to each other are used. In the XY quadrature coordinate system defined by the XY plane including the XY plane, M1 (one or more integers) × N1 (one or more integers) unit constituent regions each having a square shape on the XY plane. A virtual square grid composed of R is set. At this time, the arrangement pattern is a unit on the XY plane specified by the coordinate component x in the X-axis direction (an integer of 1 or more and M1 or less) and the coordinate component y in the Y-axis direction (an integer of 1 or more and N1 or less). In the constituent area R (x, y), the lattice point O (x, y) at which the center of gravity G1 of the different refractive index region located in the unit constituent region R (x, y) is the center of the unit constituent region R (x, y) It is defined so that the vector from the lattice point O (x, y) to the center of gravity G1 is oriented in a specific direction while being separated from y) by a distance r.

(2) As one aspect of the method for manufacturing a semiconductor light emitting element according to the present embodiment, a semiconductor light emitting element having the above-mentioned structure is manufactured. Specifically, the manufacturing method comprises a first step of forming a common substrate layer, a second step of forming an element main body on the common substrate layer, and a third step of forming a separation region in the element main body. At least prepare. In the second step, the element main body formed on the common substrate layer has a third surface and a fourth surface facing the third surface and facing the common substrate layer. Further, the element main body includes at least an active layer, a phase modulation layer, a first clad layer, and a second clad layer arranged between the third surface and the fourth surface. At the end of the second step, the basic region in the phase modulation layer is arranged in a state where a plurality of parts (each containing a plurality of different refractive index regions) which should be a plurality of phase modulation regions are separated from each other by a predetermined distance. Consists of a single layer. In the third step, the separation region formed in the element main body electrically separates a plurality of portions that should be at least a plurality of phase modulation regions. Further, the separation region is formed from the third surface to the fourth surface until it reaches the common substrate layer.

In the semiconductor light emitting element according to the present embodiment, the drive current is supplied from the second surface side electrode corresponding to the phase modulation region to the arrangement pattern (arrangement pattern of the plurality of different refractive index regions) in each of the plurality of phase modulation regions. The beam projection pattern of the light output from the light emitting surface (first surface or the second surface) and the beam projection area which is the projection range of the beam projection pattern coincide with the target beam projection pattern and the target beam projection area. It is stipulated to be. Therefore, the arrangement pattern set in each of the plurality of phase modulation regions determines the beam projection region and the beam projection pattern of the light output from the light emitting surface of the semiconductor light emitting device. In the present embodiment, one semiconductor light emitting device includes a phase modulation layer having a plurality of phase modulation regions that determine a beam projection region and a beam projection pattern of light. With this configuration, in the manufacturing method according to the present embodiment, unlike the configuration in which a plurality of semiconductor light emitting devices each having one phase modulation region (phase modulation layer) are arranged on the support substrate, a plurality of semiconductor light emitting devices are arranged. Is not required to be placed on the support substrate. As a result, it is possible to easily and highly accurately irradiate the target beam projection region with the light of the target beam projection pattern.

(3) As one aspect of the present embodiment, the semiconductor light emitting device electrically separates each of a plurality of phase modulation regions and is viewed from a direction along the Z axis (hereinafter referred to as "Z axis direction"). A separation region that electrically separates a plurality of corresponding regions in each of the active layer, the first clad layer, and the second clad layer, which sometimes overlaps with the plurality of phase modulation regions, may be further provided. Further, as one aspect of the present embodiment, the separation region optically separates a plurality of corresponding regions in each of the active layer, the phase modulation layer, the first clad layer, and the second clad layer together with the plurality of phase modulation regions. You may. Since the adjacent phase modulation regions are electrically separated by the separation region in this way, the occurrence of crosstalk between the adjacent phase modulation regions is suppressed. Further, since the adjacent phase modulation regions are also optically separated by the separation region, the occurrence of crosstalk between the adjacent phase modulation regions is further suppressed. As a result, irradiation of the desired beam projection pattern (target beam projection pattern) to the desired beam projection region (target beam projection region) is realized with even higher accuracy.

(4) As one aspect of the present embodiment, the separation region reaches the common substrate layer from the second surface toward the common substrate layer surface in the region between the adjacent phase modulation regions among the plurality of phase modulation regions. It is growing until it does. Further, the distance (shortest distance) between the tip of the separation region and the first surface side electrode is preferably half or less of the thickness of the common substrate layer along the Z-axis direction. Typically, the distance between the tip of the separation region and the first surface side electrode is preferably 70 μm or less. In this case, the occurrence of crosstalk between adjacent phase modulation regions is sufficiently suppressed.

(5) As one aspect of the present embodiment, the separation region may be a semiconductor layer modified by an electric field caused by high-intensity light irradiation. In this case, a semiconductor light emitting element in which the adjacent phase modulation regions are electrically separated and the occurrence of crosstalk between the adjacent phase modulation regions is sufficiently suppressed can be efficiently manufactured. Further, the separation region may be either a semiconductor layer insulated by impurity diffusion or an ion implantation method, or an air gap (slit) formed by dry etching or wet etching. In this case, a semiconductor light emitting element in which the adjacent phase modulation regions are electrically and optically separated and the occurrence of crosstalk between the adjacent phase modulation regions is sufficiently suppressed can be efficiently manufactured. ..

(6) As one aspect of the present embodiment, even if the arrangement pattern in each phase modulation region is determined so that the beam projection regions are equal even when the drive current is supplied from any of the second surface side electrodes. good. In this case, various applications other than the application example of the semiconductor light emitting device shown in Patent Document 1 (application example in which a laser beam is scanned against an object) become possible. For example, application to various display devices that switch and display multiple patterns in the same area of the screen, application to various types of lighting that continuously or intermittently irradiates light of the same pattern in one place, in one place. By continuously irradiating the pulsed light of the same pattern, it becomes possible to apply it to a type of laser processing in which a hole of a target pattern is formed in an object.

(7) As one aspect of the present embodiment, an arrangement pattern in each phase modulation region is determined so that the beam projection pattern becomes the same even when the drive current is supplied from any of the plurality of second surface side electrodes. You may. In this case, in addition to the same application as the application example of the semiconductor light emitting device shown in Patent Document 1 (application example in which the laser beam is scanned against the object), various applications different from the application are also possible. It will be possible. Applications different from the application examples shown in Patent Document 1 include applications to various types of illumination that continuously or intermittently irradiate the same pattern of light at one location, and continuous pulsed light of the same pattern at one location. In addition to the above-mentioned applications such as the application to laser processing of the type that pierces the target pattern hole in the object by irradiating the object, the application to the type of lighting that irradiates any part at an appropriate timing is also possible. It will be possible.

In the semiconductor light emitting element having the above-mentioned structure, the phase modulation layer optically coupled to the active layer is embedded in the basic layer and each of them is embedded in the basic layer, and the refractive index is different from that of the basic layer. It has a plurality of different refractive index regions, each of which has a rate. Further, in the unit constituent region R (x, y) constituting the virtual square grid, the center of gravity G1 of the corresponding different refractive index region is arranged away from the grid point O (x, y). Further, the direction of the vector from the grid point O to the center of gravity G1 is individually set for each unit constituent region R. In such a configuration, the phase of the beam changes according to the direction of the vector from the lattice point O to the center of gravity G1 of the corresponding different refractive index region, that is, the angular position around the lattice point of the center of gravity G1 of the different refractive index region. do. As described above, according to the present embodiment, the phase of the beam output from each of the different refractive index regions can be controlled only by changing the position of the center of gravity of the different refractive index region, and the beam projection formed as a whole can be controlled. The pattern (beam group forming an optical image) can be controlled to a desired shape. At this time, the lattice points in the virtual square lattice may be located outside the different refractive index region, or the lattice points may be located inside the different refractive index region.

(8) As one aspect of the present embodiment, when the lattice constant (substantially corresponding to the lattice spacing) of a virtual square lattice is a, the different refractive index located in the unit constituent region R (x, y). The distance r between the center of gravity G1 of the region and the lattice point O (x, y) preferably satisfies 0 ≦ r ≦ 0.3a. Further, as the original image (light image before the two-dimensional inverse Fourier transformation) that becomes the beam projection pattern of the light emitted from the semiconductor light emitting element corresponding to each of the plurality of phase modulation regions, for example, spots, three points or more. It preferably contains at least one of a spot group consisting of, a straight line, a cross, a line drawing, a grid pattern, a striped pattern, a figure, a photograph, computer graphics, and a character.

(9) In one aspect of the present embodiment, in addition to the first precondition, as the second precondition, the coordinates (x, y, z) in the XYZ orthogonal coordinate system are the moving diameters as shown in FIG. 41. Spherical coordinates (d1, θ _tilt , θ _rot ) defined by the length d1, the tilt angle θ _tilt from the Z axis, and the rotation angle θ _rot from the X axis specified on the XY plane. On the other hand, it is assumed that the relations shown by the following equations (1) to (3) are satisfied. Note that FIG. 41 is a diagram for explaining the coordinate conversion from the spherical coordinates (d1, θ _tilt , θ _rot ) to the coordinates (x, y, z) in the XYZ orthogonal coordinate system, and is a diagram for explaining the coordinates (x, y, z) represents a design optical image on a predetermined plane (target beam projection region) set in the XYZ orthogonal coordinate system which is a real space. When the target beam projection pattern corresponding to the light image output from the semiconductor light emitting element is a set of bright spots in the directions defined by the angles θ _tilt and θ _rot , the angles θ _tilt and θ _rot are given by the following equations ( The standardized wave number specified in 4) and the coordinate value k _x on the Kx axis corresponding to the X axis, and the standardized wave number specified in the following equation (5) corresponding to the Y axis and Kx. It shall be converted into the coordinate value _ky on the ky axis orthogonal to the axis. The normalized wavenumber means the wavenumber standardized with the wavenumber corresponding to the grid spacing of the virtual square grid as 1.0. At this time, in the wavenumber space defined by the Kx axis and the Ky axis, the specific wavenumber range including the beam projection pattern corresponding to the optical image is M2 (integer of 1 or more) × N2 (integer of 1 or more) having a square shape, respectively. It is composed of (integer) image area FR. The integer M2 does not have to match the integer M1. Similarly, the integer N2 does not have to match the integer N1. Further, the formula (4) and the formula (5) are disclosed in, for example, the above-mentioned Non-Patent Document 1.

As a third precondition, in the wave number space, an image region specified by a coordinate component k _x (an integer of 1 or more and M2 or less) in the Kx axis direction and a coordinate component _ky (an integer of 1 or more and N2 or less) in the Ky axis direction. Each FR (k _{x, ky} ) is specified by a coordinate component x in the X-axis direction (an integer of 1 or more and M1 or less) and a coordinate component y in the Y-axis direction (an integer of 1 or more and N1 or less). The complex amplitude F (x, y) obtained by performing a two-dimensional inverse Fourier transformation on the unit constituent region R (x, y) on the plane is given by the following equation (6) with j as an imaginary unit. Further, this complex amplitude F (x, y) is defined by the following equation (7) when the amplitude term is A (x, y) and the phase term is P (x, y). Further, as a fourth precondition, the grid point O (x, y) in which the unit constituent region R (x, y) is parallel to the X axis and the Y axis and is the center of the unit constituent region R (x, y), respectively. ) Is defined by the orthogonal s-axis and t-axis.

Under the first to fourth preconditions, the arrangement pattern of the different refractive index regions in the phase modulation layer is determined by a rotation method or an axial shift method. Specifically, in the determination of the arrangement pattern by the rotation method, a line segment connecting the lattice point O (x, y) and the center of gravity G1 of the corresponding different refractive index region in the unit constituent region R (x, y) is used. The angle φ (x, y) formed by the s axis is
φ (x, y) = C × P (x, y) + B
C: Proportional constant, for example 180 ° / π
B: An arbitrary constant, for example 0
The corresponding different refractive index regions are arranged so as to satisfy the above relationship.

In the semiconductor light emitting element having the above-mentioned structure, in the phase modulation layer, the distance r between the center (lattice point) of each unit constituent region constituting a virtual square lattice and the center of gravity G1 of the corresponding different refractive index region. Is preferably a constant value over the entire phase modulation layer (note that it is not excluded that the distance r is partially different). As a result, the phase distribution in the entire phase modulation layer (the distribution of the phase term P (x, y) in the complex amplitude F (x, y) assigned to the unit constituent region R (x, y)) is 0 to 2π (rad). ), On average, the center of gravity of the different refractive index region coincides with the grid point of the unit constituent region R in the square grid. Therefore, the two-dimensional distributed Bragg diffraction effect in the above phase modulation layer approaches the two-dimensional distributed Bragg diffraction effect when the different refractive index regions are arranged on each lattice point of the square lattice, and thus is a standing wave. Can be easily formed, and a reduction in the threshold current for oscillation can be expected.

(10) On the other hand, in the determination of the arrangement pattern by the on-axis shift method, the grid point O (x, y) is passed through the unit constituent region R (x, y) under the first to fourth preconditions. The center of gravity G1 of the different refractive index region corresponding to the straight line inclined from the axis is arranged. At that time, the line segment length r (x, y) from the lattice point O (x, y) to the center of gravity G1 of the corresponding different refractive index region is determined.
r (x, y) = C × (P (x, y) -P ₀ )
C: Proportional constant
P ₀ : An arbitrary constant, for example, 0
The corresponding different refractive index regions are arranged in the unit constituent region R (x, y) so as to satisfy the above relationship. Even when the arrangement pattern of the different refractive index region in the phase modulation layer is determined by the on-axis shift method, the same effect as that of the above-mentioned rotation method is obtained.

(11) As one aspect of the present embodiment, in at least one phase modulation region among the plurality of phase modulation regions, all of the plurality of different refractive index regions have a shape defined on the XY plane, XY. It is preferable that at least one of the area defined on the plane and the distance r defined on the XY plane match. Here, the above-mentioned "shape defined on the XY plane" also includes a combination shape of a plurality of elements constituting one different refractive index region (see FIGS. 25 (h) to 25 (k)). .. According to this, it is possible to suppress the generation of noise light and 0th order light which becomes noise in the beam projection region. The 0th-order light is light that is output in parallel in the Z-axis direction, and means light that is not phase-modulated in the phase modulation layer.

(12) As one aspect of the present embodiment, the shapes of a plurality of different refractive index regions on the XY plane are a perfect circle, a square, a regular hexagon, a regular octagon, a regular hexagon, a regular triangle, and a right-angled isosceles triangle. , Rectangle, ellipse, two circles or a shape where parts of an ellipse overlap, an oval shape, a teardrop shape, an isotropic triangle, an arrow shape, a trapezoidal shape, a pentagon, and a shape where parts of two rectangles overlap. It is preferable that it is. As shown in FIGS. 22 (h) and 38 (d), the oval shape has a dimension in the short axis direction near one end along the long axis thereof and near the other end. It is a shape obtained by deforming an ellipse so as to be smaller than the dimension in the minor axis direction. The teardrop shape deforms one end of an ellipse along its long axis into a pointed end that protrudes along its long axis, as shown in FIGS. 22 (d) and 38 (e). It is a shape obtained by doing so. In the arrow-shaped shape, as shown in FIGS. 22 (e) and 38 (g), one side of the rectangle constitutes a triangular notch, while the side facing the one side constitutes a triangular protrusion. It has a nice shape.

When the shape of the plurality of different refractive index regions on the XY plane is any of a perfect circle, a square, a regular hexagon, a regular octagon, a regular hexagon, a rectangle, and an ellipse, that is, for each different refractive index region. When the shape is mirror image symmetric (line symmetry), in the phase modulation layer, from the grid points O of each of the plurality of unit constituent regions R constituting the virtual square grid to the center of gravity G1 of the corresponding different refractive index regions. It is possible to set the angle φ formed by the heading direction and the s axis parallel to the X axis with high accuracy. Further, the shapes of a plurality of different refractive index regions on the XY plane are a regular triangle, a right-angled isosceles triangle, an isosceles triangle, a shape in which a part of two circles or an ellipse overlaps, an oval shape, and a teardrop shape. Higher light output can be obtained in either the arrow-shaped shape, the trapezoidal shape, the pentagonal shape, or the shape in which a part of two rectangles overlaps, that is, when the rotation symmetry of 180 ° is not provided.

(13) As one aspect of the present embodiment, at least one phase modulation region among the plurality of phase modulation regions surrounds an inner region composed of M1 × N1 unit constituent regions R and the outer periphery of the inner regions. It may have an outer region provided so as to. It should be noted that the outer region has a plurality of peripherals arranged so as to overlap each other with the grid points in the extended square grid defined by setting the same grid structure as the virtual square grid on the outer periphery of the virtual square grid. Includes lattice point different refractive index region. In this case, light leakage along the XY plane is suppressed, and the oscillation threshold current can be reduced.

(14) As one aspect of the present embodiment, at least one phase modulation region among the plurality of phase modulation regions is a plurality of different refractive index regions different from the plurality of different refractive index regions, that is, a plurality of lattice points. It may have a different refractive index region. The plurality of different refractive index regions are respectively arranged in the unit constituent region R of M1 × N1, and the respective center of gravity G2 is arranged so as to coincide with the lattice point O of the corresponding unit constituent region R. In this case, the combined shape composed of the different refractive index region and the lattice point different refractive index region does not have 180 ° rotational symmetry as a whole. Therefore, a higher light output can be obtained.

As described above, each of the embodiments listed in the [Explanation of Embodiments of the present invention] column is applicable to each of all the remaining embodiments or to all combinations of these remaining embodiments. ..

[Details of Embodiments of the present invention]
Hereinafter, the specific structure of the semiconductor light emitting device and the manufacturing method thereof according to the present embodiment will be described in detail with reference to the attached drawings. It should be noted that the present invention is not limited to these examples, and is indicated by the scope of the claim, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claim. Further, in the description of the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted.

(First Embodiment)
The configuration of the semiconductor light emitting device 100 according to the first embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a view of the semiconductor light emitting device 100 according to the first embodiment as viewed from the first surface side. FIG. 2 is a view of the semiconductor light emitting device 100 as viewed from the second surface side, and FIG. 3 is a cross-sectional view taken along the line III-III of FIGS. 1 and 2.

As shown in FIGS. 1 to 3, the semiconductor light emitting device 100 has a first surface 100a and a second surface 100b, and outputs light from the first surface 100a as a light emitting surface. In this embodiment, the second surface 100b functions as a support surface. The semiconductor light emitting element 100 includes a common substrate layer 101, an active layer 103, a phase modulation layer 104, a first clad layer 102, a second clad layer 106, and a pair of second surface side electrodes 108-1, 108-. 2 and a first surface side electrode 110 are provided. The phase modulation layer 104 has a pair of phase modulation regions 104-1 and 104-2 that are optically coupled to the active layer 103. The laminated structure is composed of at least the active layer 103 and the phase modulation layer 104 including the pair of phase modulation regions 104-1 and 104-2. The configuration of the laminated structure is the same in the embodiments described later. The first clad layer 102 is located on the first surface 100a side with respect to the laminated structure (including at least the active layer 103 and the phase modulation layer 104). The second clad layer 106 is located on the second surface 100b side with respect to the laminated structure (including at least the active layer 103 and the phase modulation layer 104). The second surface side electrodes 108-1 and 108-2 are the sides on which the second surface 100b is arranged with respect to the second clad layer 106, and are positions corresponding to the phase modulation regions 104-1 and 104-2, respectively. Is located in. The first surface side electrode 110 is located on the side where the first surface 100a is arranged with respect to the first clad layer 102.

The phase modulation regions 104-1 and 104-2 are a basic region 104-1a and 104-2a having a first refractive index and a plurality of different refractive index regions having a second refractive index different from the first refractive index, respectively. Includes 104-1b and 104-2b. The plurality of different refractive index regions 104-1b and 104-2b are located at locations where the center of gravity G1 is deviated by a predetermined distance r from each grid point in the virtual square grid in the basic regions 104-1a and 104-2a. They are arranged in the basic regions 104-1a and 104-2a according to the arrangement pattern such that they are located. In each of the phase modulation regions 104-1 and 104-2, the arrangement pattern of the plurality of different refractive index regions 104-1b is the second surface side electrode 108-1 or the second surface side electrode 108-1 corresponding to the phase modulation region 104-1 or 104-2. The beam projection pattern represented by the light output from the first surface 100a when the drive current is supplied from 108-2 and the beam projection region which is the projection range of the beam projection pattern are the target beam projection pattern and the target beam. It is set to match the projection area.

A beam projection region of light output when a drive current is supplied from the second surface side electrode 108-1, and a beam of light output when a drive current is supplied from the second surface side electrode 108-2. The projection area may be the same or different. Further, a beam projection pattern of light output when a drive current is supplied from the second surface side electrode 108-1, and a beam output when a drive current is supplied from the second surface side electrode 108-2. The projection patterns may be the same or different.

The "beam projection region" referred to in the present specification refers to a projection range of light output from the first surface or the second surface of the semiconductor light emitting element when a drive current is supplied from one second surface side electrode. , "Beam projection pattern" refers to a light projection pattern (light intensity pattern) within the projection range.

The active layer 103, the phase modulation layer 104, the first clad layer 102, the second clad layer 106, and the common substrate layer 101 reach the common substrate layer 101 from the second surface 100b toward the common substrate layer 101. A separation region 112 extending to is provided. The separation region 112 overlaps with the phase modulation regions 104-1 and 104-2 when viewed from the Z-axis direction (stacking direction), the active layer 103, the first clad layer 102, the second clad layer 106, and the first clad layer. It extends from the second surface 100b toward the common substrate layer 101 so as to electrically and optically separate the corresponding regions in each of the 102 and the second clad layer 106. The thickness of the portion of the common substrate layer 101 located below the separation region 112 (the shortest distance between the end surface 112a on the first surface side electrode 110 side of the separation region 112 and the first surface side electrode 110) is determined. It is less than half the thickness of the common substrate layer 101, typically 70 μm or less. As shown in FIG. 3, each portion of the semiconductor light emitting device 100 separated at the position of the separation region 112 can be regarded as an independent light emitting unit (first light emitting unit, second light emitting unit).

As shown in FIGS. 1 and 3, the first surface side electrode 110 has an opening at a position corresponding to the phase modulation regions 104-1 and 104-2 and the second surface side electrodes 108-1 and 108-2. It has 110-1 and 110-2. The first surface side electrode 110 may be a transparent electrode instead of the electrode having an opening.

The vertical relationship between the active layer 103 and the phase modulation layer 104 may be the reverse of the vertical relationship shown in FIG. Further, although the common substrate layer 101, the upper optical guide layer 105b, the lower optical guide layer 105a, the contact layer 107, the insulating layer 109, and the antireflection layer 111 are also shown in FIG. 3, the semiconductor light emitting device 100 is not always the same. You don't have to have these.

A person skilled in the art can appropriately select the manufacturing method including the main steps excluding the manufacturing steps of each layer, each region, the shape, the dimensions, and the separation region described above, based on the contents described in Patent Document 1. However, some examples are shown below. That is, an example of the material or structure of each layer shown in FIG. 3 is as follows. The common substrate layer 101 is made of GaAs. The first clad layer 102 is made of AlGaAs. The active layer 103 has a multiple quantum well structure MQW (barrier layer: AlGaAs / well layer: InGaAs). The phase modulation layer 104 includes basic regions 104-1a and 104-2a and a plurality of different refractive index regions 104-1b and 104-2b embedded in the basic regions 104-1a and 104-2a. The basic regions 104-1a and 104-2a are made of GaAs. A plurality of different refractive index regions 104-1b and 104-2b are made of AlGaAs. The upper optical guide layer 105b and the lower optical guide layer 105a are made of AlGaAs. The second clad layer 106 is made of AlGaAs. The contact layer 107 is made of GaAs. The insulating layer 109 is made of SiO ₂ or silicon nitride. The antireflection layer 111 is made of a dielectric single layer film such as silicon nitride (SiN) or silicon dioxide (SiO ₂ ) or a dielectric multilayer film.

In the manufacturing method according to the present embodiment, after the formation of the common substrate (first step), the element main body (at least, the active layer 103, the phase modulation layer 104, and the first clad layer 102) is placed on the common substrate layer 101 as described above. , Including the second clad layer 106) is formed (second step). A separation region 112 extending from the second surface 100b toward the common substrate layer 101 until it reaches the common substrate layer 101 is formed on the element main body formed as described above (third step). The separation region 112 was formed by a semiconductor layer modified by high-intensity light (electric field), a semiconductor layer insulated by either impurity diffusion and ion implantation, or by either dry etching or wet etching. It is a slit (gap). Here, as a specific method of modification by high-intensity light (electric field), for example, there is processing by a nanosecond laser or processing by an ultrashort pulse laser. The plurality of different refractive index regions 104-1b and 104-2b may be pores filled with argon, nitrogen, air, or the like. The separation region 112 extending from the second surface 100b toward the common substrate layer 101 does not need to penetrate the common substrate layer 101. However, of the thickness of the common substrate layer 101 along the Z-axis direction, the thickness of the portion where the separation region 112 is formed (between the end surface 112a on the first surface side electrode 110 side of the separation region 112 and the first surface side electrode 110). The shortest distance) is preferably half or less of the thickness of the common substrate layer 101 in order to reduce crosstalk between light emitting portions. Typically, the thickness of the unformed portion of the separation region 112 is 70 μm or less. The manufacturing method according to the present embodiment can also be applied to the manufacturing of the semiconductor light emitting element according to the second to fourth embodiments described later.

In one example, N-type impurities are added to the common substrate layer 101 and the first clad layer 102. P-type impurities are added to the second clad layer 106 and the contact layer 107. Further, the energy band gap between the first clad layer 102 and the second clad layer 106 is larger than the energy band gap between the upper optical guide layer 105b and the lower optical guide layer 105a. The energy band gap between the upper optical guide layer 105b and the lower optical guide layer 105a is set to be larger than the energy band gap of the multiple quantum well structure MQW of the active layer 103.

Next, with reference to FIGS. 4 and 5, an arrangement pattern of a plurality of different refractive index regions in each phase modulation region will be described. FIG. 4 is a schematic diagram for explaining an arrangement pattern of the different refractive index region in the phase modulation region. FIG. 5 is a diagram for explaining the positional relationship between the center of gravity G1 in the different refractive index region and the lattice point O in the virtual square lattice. Although only 12 different refractive index regions are shown in FIG. 4, a large number of different refractive index regions are actually provided. In one example, a 704 × 704 different refractive index region is provided. The arrangement pattern described here is not the arrangement pattern peculiar to the first embodiment, but the arrangement pattern of the second to fourth embodiments described later is also the same. Therefore, in FIG. 4, the reference numerals representing the phase modulation region, the basic region, and the plurality of different refractive index regions are generalized, the phase modulation region is n04-m, the basic region is n04-ma, and the plurality of different refractive index regions are n04. It is represented by -mb. In addition, "n" is a number for distinguishing an embodiment (the first embodiment is "1", the second embodiment is "2", ...), And m is a semiconductor light emitting element constituting one semiconductor light emitting module. It is a number for distinguishing, and both "n" and "m" are represented by an integer of 1 or more.

As shown in FIG. 4, the phase modulation layer n04-m has a basic region n04-ma of the first refractive index and a different refractive index region n04-mb of the second refractive index different from the first refractive index. A virtual square grid defined on the XY plane is set in the phase modulation layer n04-m including the phase modulation layer n04-m. FIG. 4 is a schematic diagram for explaining an arrangement pattern (rotation method) of the different refractive index region in the phase modulation layer. One side of the square grid is parallel to the X axis and the other side is parallel to the Y axis. At this time, the square-shaped unit constituent region R centered on the grid point O of the square grid can be set two-dimensionally over a plurality of columns along the X-axis and a plurality of rows along the Y-axis. A plurality of different refractive index regions n04-mb are provided one by one in each unit constituent region R. The planar shape of the different refractive index region n04-mb is, for example, a circular shape. In each unit constituent region R, the center of gravity G1 of the different refractive index region n04-mb is arranged away from the grid point O closest to the center of gravity G1. Specifically, the XY plane is a plane orthogonal to the thickness direction (Z axis) of each of the semiconductor light emitting elements 100-1 and 100-2 shown in FIG. 3, and the different refractive index region n04- It coincides with one surface of the phase modulation layer n04-m containing mb. Each of the unit constituent regions R constituting the square lattice is specified by the coordinate component x (integer of 1 or more) in the X-axis direction and the coordinate component y (integer of 1 or more) in the Y-axis direction, and the unit constituent region R (x). , Y). At this time, the center of the unit constituent area R (x, y), that is, the grid point is represented by O (x, y). The lattice point O may be located outside the different refractive index region n04-mb, or may be included inside the different refractive index region n04-mb. The ratio of the area S of the different refractive index region n04-mb in one unit constituent region R is referred to as a filling factor (FF). Assuming that the grid spacing of the square lattice is a, the filling factor FF of the different refractive index region n04-mb is given as S / a ² . S is the area of the different refractive index region n04-mb in the XY plane, and when the shape of the different refractive index region n04-m is, for example, a perfect circle, S = π (D / 2) using the diameter D of the perfect circle. ) Given as ² . Further, when the shape of the different refractive index region n04-mb is square, it is given as S = LA ² using the length LA of one side of the square.

In FIG. 4, the broken line indicated by x1 to x4 indicates the center position in the unit constituent area R in the X-axis direction, and the broken line indicated by y1 to y3 indicates the center position in the unit constituent area R in the Y-axis direction. Therefore, each intersection of the broken lines x1 to x4 and the broken lines y1 to y3 is the center O (1,1) to O (3,4) of each of the unit constituent regions R (1,1) to R (3,4), that is. , Indicates a grid point. This virtual square lattice has a lattice constant of a. The lattice constant a is adjusted according to the emission wavelength.

The arrangement pattern of the different refractive index region n04-mb is determined by the method described in Patent Document 1 according to the target beam projection region and the target beam projection pattern. That is, the target beam is oriented so that the center of gravity G1 of each different refractive index region n04-mb is shifted from each grid point (the intersection of the broken lines x1 to x4 and the broken lines y1 to y3) in the virtual square grid in the basic region n04-ma. The arrangement pattern is determined by determining the original pattern corresponding to the projection region and the target beam projection pattern according to the phase obtained by the inverse Fourier transformation. As described in Patent Document 1, it is desirable that the distance r (see FIG. 5) deviated from each lattice point is in the range of 0 <r ≦ 0.3a when the lattice constant of the square lattice is a. The distance r deviated from each lattice point is usually the same over all phase modulation regions and all different refractive index regions, but the distance r in some phase modulation regions is set to other phase modulation regions. The value may be different from the distance r in, or the distance r in a part of the different refractive index region may be different from the distance r in the other different refractive index region. Note that FIG. 5 is a diagram for explaining an example of an arrangement pattern (rotation method) determined by the rotation method, and FIG. 5 shows the configuration of the unit configuration region R (x, y). The distance r from the lattice point to the different refractive index region n04-mb is indicated by r (x, y).

As shown in FIG. 5, the unit constituent regions R (x, y) constituting the square grid are defined by the s-axis and the t-axis orthogonal to each other at the grid points O (x, y). The s-axis is an axis parallel to the X-axis and corresponds to the broken lines x1 to x4 shown in FIG. The t-axis is an axis parallel to the Y-axis and corresponds to the broken lines y1 to y3 shown in FIG. In this way, in the s-t plane that defines the unit constituent region R (x, y), the angle formed by the direction from the grid point O (x, y) toward the center of gravity G1 and the s axis is φ (x, y). Given. When the rotation angle φ (x, y) is 0 °, the direction of the vector connecting the lattice point O (x, y) and the center of gravity G1 coincides with the positive direction of the s axis. Further, the length (corresponding to the distance r) of the vector connecting the grid point O (x, y) and the center of gravity G1 is given by r (x, y).

As shown in FIG. 4, in the phase modulation layer n04-m, the rotation angle φ (x, y) around the lattice point O (x, y) of the center of gravity G1 in the different refractive index region n04-mb is the target. It is set independently for each unit constituent area R according to the beam projection pattern (optical image). The rotation angle φ (x, y) has a specific value in the unit constituent region R (x, y), but is not always represented by a specific function. That is, the rotation angle φ (x, y) is determined from the phase term of the complex amplitude obtained by transforming the target beam projection pattern on the wavenumber space and performing the two-dimensional reciprocal Fourier transform on a certain wavenumber range in the wavenumber space. To. When calculating the complex amplitude distribution (complex amplitude of each unit constituent region R) from the target beam projection pattern, an iterative algorithm such as the Gerchberg-Saxton (GS) method, which is generally used when calculating hologram generation, is applied. By doing so, the reproducibility of the target beam projection pattern is improved.

FIG. 6 is a diagram for explaining the relationship between the target beam projection pattern (optical image) output from the semiconductor light emitting device 100 and the distribution of the rotation angle φ (x, y) in the phase modulation layer n04-m. .. Specifically, the target beam projection region (the installation surface of the design optical image represented by the coordinates (x, y, z) in the XYZ Cartesian coordinate system), which is the projection range of the target beam projection pattern, is placed on the wave number space. Consider the Kx-Ky plane obtained by conversion. The Kx axis and the Ky axis that define the Kx-Ky plane are orthogonal to each other, and each of them sets the projection direction of the target beam projection pattern from the normal direction (Z-axis direction) of the first surface 100a to the first surface 100a. The angle with respect to the normal direction when shaken to is associated with the above equations (1) to (5). On this Kx-Ky plane, it is assumed that each specific region including the target beam projection pattern is composed of square-shaped M2 (integer of 1 or more) x N2 (integer of 1 or more) image region FR. .. Further, a virtual square lattice set on the XY plane on the phase modulation layer n04-m is composed of M1 (integer of 1 or more) × N1 (integer of 1 or more) unit constituent regions R. It shall be. The integer M2 does not have to match the integer M1. Similarly, the integer N2 does not have to match the integer N1. At this time, the image region FR in the Kx-Ky plane specified by the coordinate component k _x in the Kx-axis direction (amplitude of 1 or more and M2 or less) and the coordinate component ky in the Ky-axis direction ( _amplitude of 1 or more and N2 or less). (K _x , _ky ) Each is a unit constituent area R specified by a coordinate component x (1 or more and an integer of M1 or less) in the X-axis direction and a coordinate component y (an integer of 1 or more and N1 or less) in the Y-axis direction. The complex amplitude F (x, y) in the unit constituent region R (x, y) obtained by the two-dimensional inverse Fourier transformation to (x, y) is given by the following equation (8) with j as an imaginary unit.

Further, in the unit constituent region R (x, y), when the amplitude term is A (x, y) and the phase term is P (x, y), the complex amplitude F (x, y) is expressed by the following equation. Specified by (9).

As shown in FIG. 6, in the range of the coordinate components x = 1 to M1 and y = 1 to N1, the amplitude term in the complex amplitude F (x, y) of the unit constituent region R (x, y) is A ( The distribution of x, y) corresponds to the intensity distribution on the XY plane. Further, in the range of x = 1 to M1 and y = 1 to N1, the distribution of the phase term in the complex amplitude F (x, y) of the unit constituent region R (x, y) is X (x, y). -Corresponds to the phase distribution on the Y plane. The rotation angle φ (x, y) in the unit constituent region R (x, y) is obtained from P (x, y) as described later, and has a range of coordinate components x = 1 to M1 and y = 1 to N1. In, the distribution of the rotation angle φ (x, y) of the unit constituent region R (x, y) corresponds to the rotation angle distribution on the XY plane.

The center Q of the beam projection pattern on the Kx-Ky plane is located on the axis perpendicular to the first surface 100a, and FIG. 6 shows four quadrants with the center Q as the origin. There is. FIG. 6 shows a case where an optical image is obtained in the first quadrant and the third quadrant as an example, but it is also possible to obtain an image in the second quadrant and the fourth quadrant, or all quadrants. In this embodiment, as shown in FIG. 6, a point-symmetrical pattern with respect to the origin is obtained. FIG. 6 shows, as an example, a case where a pattern in which the letter “A” is rotated by 180 ° in the third quadrant and the letter “A” is rotated by 180 ° in the first quadrant is obtained. In the case of a rotationally symmetric optical image (for example, a cross, a circle, a double circle, etc.), they are overlapped and observed as one optical image.

The beam projection pattern (light image) output from the semiconductor light emitting element 100 is a spot group consisting of three or more points, a straight line, a cross, a line drawing, a lattice pattern, a photograph, a striped pattern, CG (computer graphics), and characters. It is an optical image corresponding to the design optical image (original image) represented by at least one of them. Here, in order to obtain the target beam projection pattern, the rotation angle φ (x, y) of the different refractive index region n04-mb in the unit constituent region R (x, y) is determined by the following procedure.

In the unit constituent region R (x, y), as described above, the center of gravity G1 of the different refractive index region n04-mb is only the distance r (value of r (x, y)) from the lattice point O (x, y). They are placed apart. At this time, the different refractive index region n04-mb is arranged in the unit constituent region R (x, y) so that the rotation angle φ (x, y) satisfies the following relationship.
φ (x, y) = C × P (x, y) + B
C: Proportional constant, for example 180 ° / π
B: An arbitrary constant, for example 0
The proportionality constant C and the arbitrary constant B have the same values for all the unit constituent regions R.

That is, when it is desired to obtain a target beam projection pattern, a pattern formed on the Kx-Ky plane projected on the wave frequency space is formed on the unit constituent region R (x,) on the XY plane on the phase modulation layer n04-m. Two-dimensional inverse Fourier transformation is performed on y), and the rotation angle φ (x, y) corresponding to the phase term P (x, y) of the complex amplitude F (x, y) is set to the unit constituent region R (x, y). ) May be given to the different refractive index region n04-mb. The far-field image after the two-dimensional inverse Fourier transform of the laser beam can be various types such as a single or multiple spot shape, an annular shape, a linear shape, a character shape, a double annular shape, or a Lager Gaussian beam shape. Can take the shape of. Since the target beam projection pattern is represented by wave number information in the wave number space (on the Kx-Ky plane), a bitmap image or the like in which the target beam projection pattern is represented by two-dimensional position information or the like. In the case of, it is advisable to perform a two-dimensional reciprocal Fourier transform after once converting to wavenumber information.

As a method of obtaining the intensity distribution and the phase distribution from the complex amplitude distribution on the XY plane obtained by the two-dimensional inverse Fourier transform, for example, the intensity distribution (amplitude term A (x, y) on the XY plane) The distribution) can be calculated by using the abs function of the numerical analysis software "MATLAB" of MathWorks, and the phase distribution (distribution of the phase term P (x, y) on the XY plane) can be calculated. It can be calculated by using the angle function of MATLAB.

As described above, if the arrangement pattern of the different refractive index region n04-mb is determined, the light of the target beam projection region and the target beam projection pattern can be output from the first surface 100a of the semiconductor light emitting element 100 to the beam projection region. .. The target beam projection pattern can be arbitrarily determined by the designer, and may be a spot group consisting of three or more points, a straight line, a line drawing, a cross, a figure, a photograph, CG (computer graphics), characters, and the like. .. Within the XY plane of each phase modulation region, all different refractive index regions n04-mb have the same figure, the same area, and / or the same distance r. Further, the plurality of different refractive index regions n04-b may be formed so as to be superposed by a translation operation or a combination of a translation operation and a rotation operation. In this case, it is possible to suppress the generation of noise light and zero-order light that becomes noise in the beam projection region. Here, the 0th-order light is light that is output in parallel in the Z-axis direction, and is light that is not phase-modulated in the phase modulation layer n04-m.

Here, FIG. 7 shows an example of the phase distribution among the complex amplitude distributions obtained by inverse Fourier transforming the target beam projection pattern and the corresponding original pattern. FIG. 7 (a) shows an example of a target beam projection pattern obtained when a drive current is supplied from the second surface side electrode 108-1, and FIG. 7 (b) shows the drive current from the second surface side electrode 108-2. An example of the target beam projection pattern obtained when supplied is shown. 7 (c) and 7 (d) are among the complex amplitude distributions obtained by inverse Fourier transforming the original patterns corresponding to the beam projection patterns of FIGS. 7 (a) and 7 (b), respectively. Shows the phase distribution of. Both FIGS. 7 (c) and 7 (d) are composed of 704 × 704 elements, and represent an angle distribution of 0 to 2π depending on the shade of color. The black part represents the angle 0.

Next, a light emitting device including the semiconductor light emitting element 100 will be described with reference to FIG. FIG. 8 is a block diagram showing a configuration of a light emitting device including the semiconductor light emitting device 100. As shown in FIG. 8, the light emitting device 140 includes a semiconductor light emitting element 100, a power supply circuit 141, a control signal input circuit 142, and a drive circuit 143. The power supply circuit 141 supplies power to the drive circuit 143 and the semiconductor light emitting element 100. The control signal input circuit 142 transmits a control signal supplied from the outside of the light emitting device 140 to the drive circuit 143. The drive circuit 143 supplies a drive current to the semiconductor light emitting element 100. The drive circuit 143 and the semiconductor light emitting device 100 are connected by two drive lines 144-1 and 144-2 for supplying a drive current and one common potential line 145. The drive lines 144-1 and 144-2 are connected to the second surface side electrodes 108-1 and 108-2, respectively. The common potential line 145 is connected to the first surface side electrode 110. In FIG. 8, the semiconductor light emitting element 100 shown above the drive circuit 143 and the semiconductor light emitting element 100 shown below the drive circuit 143 are the first surface and the second surface of one semiconductor light emitting element 100, respectively. Represents a face.

The drive lines 144-1 and 144-2 may be driven selectively or simultaneously depending on the application. Further, the drive circuit 143 may be configured separately from the semiconductor light emitting element 100, or may be integrally formed on the common substrate layer 101 of the semiconductor light emitting element 100.

The light emitting device 140 including the semiconductor light emitting device 100 configured as described above operates as follows. That is, a drive current is supplied from the drive circuit 143 between any of the drive lines 144-1 and 144-2 and the common potential line 145. In the light emitting portion corresponding to the second surface side electrode connected to the drive line to which the drive current is supplied, recombination of electrons and holes occurs in the active layer 103, and the active layer 103 in the light emitting portion emits light. The light obtained by the light emission is efficiently confined by the first clad layer 102 and the second clad layer 106. The light emitted from the active layer 103 is incident inside the corresponding phase modulation region, and a predetermined mode is formed by the confinement effect due to the two-dimensional feedback by the phase modulation region. By injecting sufficient electrons and holes into the active layer, the light incident on the phase modulation region oscillates in a predetermined mode. The light forming the predetermined oscillation mode undergoes phase modulation according to the arrangement pattern of the different refractive index region, and the light subjected to the phase modulation is the light expressing the beam projection pattern according to the arrangement pattern on the first surface side. It is emitted from the electrode side to the outside (beam projection area).

In the present embodiment, the semiconductor light emitting element 100 is a single element including a phase modulation layer 104 having a pair of phase modulation regions 104-1 and 104-2. Therefore, unlike the configuration in which a plurality of semiconductor light emitting elements each having one phase modulation region (phase modulation layer) are arranged on the support substrate, a process in which the plurality of semiconductor light emitting elements are arranged on the support substrate is required. Is not considered. Therefore, according to the present embodiment, it is possible to easily and highly accurately irradiate the target beam projection region with the light of the target beam projection pattern.

Further, in the present embodiment, the active layer 103, the phase modulation layer 104, the first clad layer 102, the second clad layer 106, and the common substrate layer 101 have the phase modulation region 104-1 when viewed from the Z-axis direction. , 104-2 is provided with a separation region 112 that electrically and optically separates the corresponding regions that overlap. Since the adjacent phase modulation regions 104-1 and 104-2 are electrically and optically separated by the separation region 112, the occurrence of crosstalk between the adjacent phase modulation regions 104-1 and 104-2 is suppressed. Will be done. As a result, irradiation of a desired beam projection region with light of a desired beam projection pattern is realized with even higher accuracy.

In the present embodiment, in each of the phase modulation regions 104-1 and 104-2 so that the beam projection regions are equal when the drive current is supplied from any of the second surface side electrodes 108-1 and 108-2. The arrangement pattern may be set (however, the beam projection pattern is arbitrary). With such a configuration, various applications other than the application example of the semiconductor light emitting device shown in Patent Document 1 (application example in which a laser beam is scanned against an object) are possible. For example, according to the form of Mr. Honji, (a) application to various display devices of the type that switches and displays two patterns in the same area of the screen, (b) continuous or intermittent light of the same pattern in one place. It is possible to apply it to various types of lighting that irradiate the object, and (c) it can be applied to laser processing of the type that drills a hole of the target pattern in the object by continuously irradiating the pulsed light of the same pattern at one place. Is.

As an example of the application (a) in the first embodiment, the pattern of × as shown in FIG. 7 (a) and the pattern of ○ as shown in FIG. 7 (b) are instructed by the user or appropriately. There is an application such as switching and displaying at the same position on the screen at the timing of.

As an example of the application (a) in the first embodiment, both the arrangement pattern in the first phase modulation region 104-1 and the arrangement pattern in the second phase modulation region 104-2 have the same beam projection region and the same beam projection pattern. Is set to be obtained. The beam projection pattern is, for example, a beam projection pattern having uniform brightness over the entire or part of the beam projection region. When bright lighting is required, drive current is supplied from both the second surface side electrodes 108-1 and 108-2, and when dark lighting is sufficient, either the second surface side electrodes 108-1 or 108-2 is supplied. There are applications such as supplying drive current from only one of them.

As an example of the application (c) in the first embodiment, both the arrangement pattern in the first phase modulation region 104-1 and the arrangement pattern in the second phase modulation region 104-2 have the same beam projection region and the same beam projection pattern. Set to be obtained. The beam projection area is set to the position where the hole of the workpiece is to be drilled, and the beam projection pattern is the pattern of the shape of the hole to be drilled. There is an application such as supplying pulse currents alternately from both the second surface side electrodes 108-1 and 108-2. In this case, the pulse interval of each light emitting unit can be lengthened. Therefore, it is possible to obtain a higher peak output from each light emitting unit, and it is possible to obtain a higher output.

Further, in the present embodiment, the phase modulation regions 104-1 and 104- are arranged so that the beam projection patterns are the same when the drive current is supplied from any of the second surface side electrodes 108-1 and 108-2. 2 The arrangement pattern in each may be defined (however, the beam projection area is arbitrary). Even in the case of such a configuration, various applications other than the application example of the semiconductor light emitting device shown in Patent Document 1 (application example in which the laser beam is scanned against the object) are possible. For example, in addition to the above-mentioned applications (a) to (c), it is also possible to apply to a type of lighting that irradiates two places at appropriate timings.

(Second Embodiment)
The second embodiment is an embodiment having three or more pairs of phase modulation regions and second surface side electrodes, which were two (pair) in the first embodiment, and arranging them one-dimensionally. In other words, this second embodiment is an embodiment in which the number of light emitting parts, which was two in the first embodiment, is increased to three or more, and the light emitting parts are further arranged one-dimensionally. It is the same as the first embodiment except for the above points.

The configuration of the semiconductor light emitting device 200 according to the second embodiment will be described with reference to FIGS. 9 to 11. FIG. 9 is a view of the semiconductor light emitting device 200 according to the second embodiment as viewed from the first surface side. FIG. 10 is a view of the semiconductor light emitting device 200 as viewed from the second surface side. FIG. 11 is a cross-sectional view taken along the line XX of FIGS. 9 and 10. 9 to 11 show an example in which five light emitting units (first light emitting unit to fifth light emitting unit) are arranged in a straight line, but the number of light emitting units may be other than five. Also, the one-dimensional arrangement may be on a curve.

As shown in FIGS. 9 to 11, the semiconductor light emitting device 200 has a first surface 200a and a second surface 200b, and outputs light from the first surface 200a as a light emitting surface. In this embodiment, the second surface 200b functions as a support surface. The semiconductor light emitting element 200 includes a common substrate layer 201, an active layer 203, a phase modulation layer 204, a first clad layer 202, a second clad layer 206, and a plurality of second surface side electrodes 208-1 to 208-. 5 and a first surface side electrode 210 are provided. The phase modulation layer 204 has a plurality of phase modulation regions 204-1 to 204-5 optically coupled to the active layer 203. At least, the laminated structure is composed of the active layer 203 and the phase modulation layer 204 including the plurality of phase modulation regions 204-1 to 204-5. The first clad layer 202 is located on the side where the first surface 200a is arranged with respect to the laminated structure (including at least the active layer 203 and the phase modulation layer 204). The second clad layer 206 is located on the side where the second surface 200b is arranged with respect to the laminated structure (including at least the active layer 203 and the phase modulation layer 204). The second surface side electrodes 208-1 to 208-5 are the sides on which the second surface 200b is arranged with respect to the second clad layer 206, and are the positions corresponding to the phase modulation regions 204-1 to 204-5, respectively. Is located in. The first surface side electrode 210 is located on the side where the first surface 200a is arranged with respect to the first clad layer 202.

The phase modulation regions 204-1 to 204-5 are a basic region 204-1a to 204-5a having a first refractive index and a plurality of different refractive index regions having a second refractive index different from the first refractive index, respectively. Includes 204-1b to 204-5b. The plurality of different refractive index regions 204-1b to 204-5b are locations where the center of gravity G1 is deviated by a predetermined distance r from each grid point O in the virtual square grid in the basic regions 204-1a to 204-5a. It is arranged in the basic regions 204-1a to 204-5a according to the arrangement pattern such that it is located in. The arrangement pattern of the different refractive index regions 204-1b to 204-5b in each of the phase modulation regions 204-1 to 204-5 is the second surface side electrode 208-1 corresponding to the phase modulation regions 204-1 to 204-5. The beam projection pattern represented by the light output from the first surface 200a when the drive current is supplied from ~ 208-5 and the beam projection which is the projection range of the beam projection pattern are the target beam projection pattern and the target beam. It is set to be a projection area.

The beam projection region of the light output when the drive current is supplied from the second surface side electrodes 208-1 to 208-5 may be all the same, or at least a part thereof is different from the others. May be good. Further, the beam projection pattern of the light output when the drive current is supplied from the second surface side electrodes 208-1 to 208-5 may be all the same, or at least a part thereof is different from the others. May be.

The active layer 203, the phase modulation layer 204, the first clad layer 202, the second clad layer 206, and the common substrate layer 201 reach the common substrate layer 201 from the second surface 200b toward the common substrate layer 201. A separation region 212 extending to is provided. The separation region 212 overlaps with the phase modulation regions 204-1 to 204-5 when viewed from the Z-axis direction (stacking direction), the active layer 203, the first clad layer 202, the second clad layer 206, and the first clad layer. It extends from the second surface 200b toward the common substrate layer 201 so as to electrically and optically separate the corresponding regions in 202 and the second clad layer 206, respectively. The thickness of the portion of the common substrate layer 201 located below the separation region 212 (the shortest distance between the end surface 212a on the first surface side electrode 210 side of the separation region 212 and the first surface side electrode 210) is Z. It is less than half the thickness of the common substrate layer 201 along the axial direction, typically 70 μm or less. As shown in FIG. 11, each portion of the semiconductor light emitting element 100 separated at the position of the separation region 212 can be regarded as an independent light emitting unit (first light emitting unit to fifth light emitting unit). Further, the manufacturing process of the separation region 212 is the same as that of the first embodiment.

As shown in FIGS. 9 and 11, the first surface side electrode 210 has an opening at a position corresponding to the phase modulation regions 204-1 to 204-5 and the second surface side electrodes 208-1 to 208-5. It has 210-1 to 210-5. The first surface side electrode 210 may be a transparent electrode instead of the electrode having an opening.

The vertical relationship between the active layer 203 and the phase modulation layer 204 may be the reverse of the vertical relationship shown in FIG. Further, FIG. 11 also shows a common substrate layer 201, an upper optical guide layer 205b, a lower optical guide layer 205a, a contact layer 207, an insulating layer 209, and an antireflection layer 211, but the semiconductor light emitting element 200 is not necessarily the same. You don't have to have these.

The manufacturing methods including the main steps excluding the manufacturing steps of each layer, each region, the shape, the dimensions, and the separation region described above are based on the contents of Patent Document 1 as in the first embodiment. Those skilled in the art can select it as appropriate, but some examples are shown below. That is, an example of the material or structure of each layer shown in FIG. 11 is as follows. The common substrate layer 201 is made of GaAs. The first clad layer 202 is made of AlGaAs. The active layer 203 has a multiple quantum well structure MQW (barrier layer: AlGaAs / well layer: InGaAs). The phase modulation layer 204 includes a basic region 204-1a to 204-5a and a plurality of different refractive index regions 204-1b to 204-5b embedded in the basic regions 204-1a to 204-5a. The basic regions 204-1a to 204-5a are made of GaAs. A plurality of different refractive index regions 204-1b to 204-5b are made of AlGaAs. The upper optical guide layer 205b and the lower optical guide layer 205a are made of AlGaAs. The second clad layer 206 is made of AlGaAs. The contact layer 207 is made of GaAs. The insulating layer 209 is made of SiO ₂ or silicon nitride. The antireflection layer 211 is made of a dielectric single layer film such as silicon nitride (SiN) or silicon dioxide (SiO ₂ ) or a dielectric multilayer film. The separation region 212 was formed by a semiconductor layer modified by high-intensity light (electric field), a semiconductor layer insulated by either impurity diffusion and ion implantation, or by either dry etching or wet etching. It is a slit (gap). Here, as a specific method of modification by high-intensity light (electric field), for example, there is processing by a nanosecond laser or processing by an ultrashort pulse laser. The plurality of different refractive index regions 204-1b to 204-5b may be pores filled with argon, nitrogen, air, or the like.

In one example, N-type impurities are added to the common substrate layer 201 and the first clad layer 202. P-type impurities are added to the second clad layer 206 and the contact layer 207. Further, the energy band gap between the first clad layer 202 and the second clad layer 206 is larger than the energy band gap between the upper optical guide layer 205b and the lower optical guide layer 205a. The energy band gap between the upper optical guide layer 205b and the lower optical guide layer 205a is set to be larger than the energy band gap of the multiple quantum well structure MQW of the active layer 203.

Here, in FIGS. 12 and 13, the phase distribution of the target beam projection pattern and the complex amplitude distribution obtained by inverse Fourier transforming the corresponding original pattern in the present embodiment and the third embodiment described later is shown. An example is shown. 12 (a) to 12 (c) show the target beam projection patterns obtained when the drive current is supplied from the second surface side electrodes of the first light emitting unit, the third light emitting unit, and the fifth light emitting unit, respectively. An example is shown. 12 (d) to 12 (f) show the complex amplitude distributions obtained by inverse Fourier transforming the original patterns corresponding to the beam projection patterns of FIGS. 12 (a) to 12 (c), respectively. Shows the phase distribution of. 13 (a) to 13 (c) show the target beam projection patterns obtained when the drive current is supplied from the second surface side electrodes of the first light emitting unit, the third light emitting unit, and the fifth light emitting unit, respectively. Another example is shown. 13 (d) to 13 (f) are complex amplitude distributions obtained by inverse Fourier transforming the original patterns corresponding to the beam projection patterns of FIGS. 13 (a) to 13 (c), respectively. Shows the phase distribution of. 12 (d) to 12 (f) and 13 (d) to 13 (f) are both composed of elements of 704 × 704, and the distribution of angles from 0 to 2π is distributed depending on the shade of color. Represents. The black part represents the angle 0.

Next, with reference to FIG. 14, the configuration of the light emitting device including the semiconductor light emitting device 200 will be described. FIG. 14 is a block diagram showing a configuration of a light emitting device including a semiconductor light emitting device 200. As shown in FIG. 14, the light emitting device 240 includes a semiconductor light emitting element 200, a power supply circuit 241, a control signal input circuit 242, and a drive circuit 243. The power supply circuit 241 supplies power to the drive circuit 243 and the semiconductor light emitting device 200. The control signal input circuit 242 transmits a control signal supplied from the outside of the light emitting device 240 to the drive circuit 243. The drive circuit 243 supplies a drive current to the semiconductor light emitting element 200. The drive circuit 243 and the semiconductor light emitting element 200 are connected by a plurality of drive lines 244-1 to 244-5 for supplying a drive current and one common potential line 245. The drive lines 244-1 to 244-5 are connected to the second surface side electrodes 208-1 to 208-5, respectively. The common potential line 245 is connected to the first surface side electrode 210. In FIG. 14, the semiconductor light emitting device 200 shown above the drive circuit 243 and the semiconductor light emitting device 200 shown below the drive circuit 243 are the first surface and the second surface of one semiconductor light emitting device 200, respectively. Represents a face.

The drive lines 244-1 to 244-5 may be selectively driven or at least two may be driven at the same time depending on the application. Further, the drive circuit 243 may be configured separately from the semiconductor light emitting device 200, or may be integrally formed on the common substrate layer 201 of the semiconductor light emitting device 200.

The light emitting device 240 including the semiconductor light emitting device 200 configured as described above operates as follows. That is, a drive current is supplied from the drive circuit 243 between any of the drive lines 244-1 to 244-5 and the common potential line 245. In the light emitting portion corresponding to the second surface side electrode connected to the drive line to which the drive current is supplied, electrons and holes are recombined in the active layer 203, and the active layer 203 in the light emitting portion emits light. The light obtained by the light emission is efficiently confined by the first clad layer 202 and the second clad layer 206. The light emitted from the active layer 203 is incident inside the corresponding phase modulation region and forms a predetermined mode by the confinement effect of the two-dimensional feedback by the phase modulation region. By injecting sufficient electrons and holes into the active layer, the light incident on the phase modulation region oscillates in a predetermined mode. The light forming the predetermined oscillation mode undergoes phase modulation according to the arrangement pattern of the different refractive index region, and the light subjected to the phase modulation is the light expressing the beam projection pattern according to the arrangement pattern on the first surface side. It is emitted from the electrode side to the outside (beam projection area).

Also in this embodiment, the semiconductor light emitting element 200 is a single element including the phase modulation layer 204 having a plurality of phase modulation regions 204-1 to 204-5. Therefore, unlike the configuration in which a plurality of semiconductor light emitting elements each having one phase modulation region (phase modulation layer) are arranged on the support substrate, a process in which the plurality of semiconductor light emitting elements are arranged on the support substrate is required. Is not considered. Therefore, it is easy and highly accurate to irradiate the target beam projection area with the light of the target beam projection pattern.

Further, also in the present embodiment, the active layer 203, the phase modulation layer 204, the first clad layer 202, the second clad layer 206, and the common substrate layer 201 are covered from the second surface 200b toward the common substrate layer 201. A separation region 212 extending until it reaches the common substrate layer 201 is provided. Since the adjacent phase modulation regions 204-1 to 204-5 are electrically and optically separated by the separation region 212, the occurrence of crosstalk between the adjacent phase modulation regions 204-1 to 204-5 is suppressed. Will be done. As a result, irradiation of a desired beam projection region with light of a desired beam projection pattern is realized with even higher accuracy.

Further, also in the present embodiment, the phase modulation regions 204-1 to 204-so that the beam projection regions are equal even when the drive current is supplied from any of the second surface side electrodes 208-1 to 208-5. 5 Arrangement patterns may be set for each (however, the beam projection pattern is arbitrary). In the case of such a configuration, various applications other than the application example of the semiconductor light emitting element shown in Patent Document 1 (application example in which the laser beam is scanned against the object) are possible. For example, according to the present embodiment, (a) application to various display devices of a type in which three or more patterns are switched and displayed in the same area of the screen, and (b) continuous light of the same pattern in one place. Alternatively, it can be applied to various types of lighting that irradiate intermittently, and (c) laser processing that creates holes in the target pattern in the object by continuously irradiating pulsed light of the same pattern at one location. It can be applied.

As an example of the application (a) in the second embodiment, in addition to the pattern of × as shown in FIG. 7 (a) and the pattern of ○ as shown in FIG. 7 (b), Δ, □ Other patterns such as, etc. are switched and displayed at the same position on the screen at the user's instruction or at an appropriate timing, and slightly different patterns as shown in FIGS. 12 and 13 are continuously switched and displayed. There are applications such as displaying animation in one area.

As an example of the application (a) in the second embodiment, there is an application in which the lighting shown as the application (a) in the first embodiment is changed so as to be switchable in multiple stages.

As an example of the application (c) in the third embodiment, it seems that the laser processing shown as the application (c) in the first embodiment is changed so that a plurality of second surface side electrodes are sequentially pulse-driven. There is an application. In this case, since the pulse interval of each light emitting unit can be lengthened, a higher peak output can be obtained from each light emitting unit, and a larger output can be obtained.

Further, also in the present embodiment, the phase modulation regions 204-1 to 204-so that the beam projection patterns are the same when the drive current is supplied from any of the second surface side electrodes 208-1 to 208-5. 5 The arrangement pattern in each may be set (however, the beam projection area is arbitrary). In the case of such a configuration, the same application as the application example of the semiconductor light emitting device (application example in which the laser beam is scanned against the object) shown in Patent Document 1 is possible, and the application is different from that. Various applications are also possible. As an application different from the application example shown in Patent Document 1, in addition to the above-mentioned applications (a) to (c), it is also possible to apply to a type of lighting that irradiates an arbitrary place at a desired timing. Become.

(Third Embodiment)
The third embodiment is an embodiment in which the one-dimensional arrangement of the phase modulation region and the second surface side electrode in the second embodiment is changed to the two-dimensional arrangement. In other words, this second embodiment is an embodiment in which the one-dimensional arrangement of a plurality of light emitting units is changed to a two-dimensional arrangement as in the first embodiment, and the second embodiment is different from the point where such a change is made. Is similar to.

The configuration of the semiconductor light emitting element 300 according to the third embodiment will be described with reference to FIGS. 15 to 17. 15 is a view of the semiconductor light emitting device 300 according to the third embodiment as viewed from the first surface side, FIG. 16 is a view of the semiconductor light emitting device 300 as viewed from the second surface side, and FIG. 17 is a view of FIGS. 15 and 15. It is sectional drawing along the XVI-XVI line of 16. 15 to 17 show an example in which 15 light emitting units (first light emitting unit to 15th light emitting unit) are arranged in 3 rows and 5 columns, but the number of light emitting units is other than 15. Also, the two-dimensional arrangement may be arbitrary.

As shown in FIGS. 15 to 17, the semiconductor light emitting device 300 has a first surface 300a and a second surface 300b, and outputs light from the first surface 300a as a light emitting surface. In this embodiment, the second surface 300b functions as a support surface. The semiconductor light emitting device 300 includes a common substrate layer 301, an active layer 303, a phase modulation layer 304, a first clad layer 302, a second clad layer 306, and a plurality of second surface side electrodes 300-1 to 308-. A 15 and a first surface side electrode 310 are provided. The phase modulation layer 304 has a plurality of phase modulation regions 304-1 to 304-15 optically coupled to the active layer 303. The laminated structure is composed of at least the active layer 303 and the phase modulation layer 304 including the plurality of phase modulation regions 304-1 to 304-15. The first clad layer 302 is located on the side where the first surface 300a is arranged with respect to the laminated structure (including at least the active layer 303 and the phase modulation layer 304). The second clad layer 306 is located on the side where the second surface 300b of the laminated structure (including at least the active layer 303 and the phase modulation layer 304) is arranged. The second surface side electrodes 308-1 to 308-15 are the sides on which the second surface 300b is arranged with respect to the second clad layer 306, and are positions corresponding to the phase modulation regions 304-1 to 304-15, respectively. Is located in. The first surface side electrode 310 is located on the side where the first surface 300a is arranged with respect to the first clad layer 302.

The phase modulation regions 304-1 to 304-15 are the basic regions 304-1a to 304-15a having the first refractive index and the plurality of different refractive index regions 304 having a second refractive index different from the first refractive index, respectively. -1b to 304-15b are included. The plurality of different refractive index regions 304-1b to 304-15b are locations where their respective center of gravity G1 is deviated by a predetermined distance r from each grid point O in the virtual square grid in the basic regions 304-1a to 304-15a. It is arranged in the basic regions 304-1a to 304-15a according to the arrangement pattern such that it is located in. The arrangement pattern of the different refractive index regions 304-1b to 304-15b in each of the phase modulation regions 304-1 to 304-15 is the second surface side electrode 308- corresponding to the phase modulation regions 304-1 to 304-15. The beam projection pattern represented by the light output from the first surface 300a when the drive current is supplied from 1 to 308-15 and the beam projection region which is the projection range of the beam projection pattern are the target beam projection patterns. It is set to match the target beam projection area.

The beam projection region of the light output when the drive current is supplied from the second surface side electrodes 308-1 to 308-15 may be all the same, or at least a part thereof may be different from the others. May be good. Further, the beam projection pattern of the light output when the drive current is supplied from the second surface side electrodes 308-1 to 308-15 may be all the same, or at least a part thereof is different from the others. May be.

The active layer 303, the phase modulation layer 304, the first clad layer 302, the second clad layer 306, and the common substrate layer 301 reach the common substrate layer 301 from the second surface 300b toward the common substrate layer 301. A separation region 312 extending to is provided. The separation region 312 overlaps with the phase modulation regions 304-1 to 204-5 when viewed from the Z-axis direction (stacking direction), the active layer 303, the first clad layer 302, the second clad layer 306, and the first clad layer. It extends from the second surface 300b toward the common substrate layer 301 so as to electrically and optically separate the corresponding regions in each of the 302 and the second clad layer 306. The thickness of the portion of the common substrate layer 301 located at the lower part of the separation region 312 (the shortest distance between the end surface 312a on the first surface side electrode 310 side of the separation region 312 and the first surface side electrode 310) is Z. It is less than half the thickness of the common substrate layer 201 along the axial direction, and typically 70 μm or less. As shown in FIG. 17, each portion of the semiconductor light emitting device 300 separated at the position of the separation region 312 can be regarded as an independent light emitting unit (first light emitting unit to fifteenth light emitting unit). Further, the manufacturing process of the separation region 312 is the same as that of the first embodiment.

As shown in FIGS. 15 and 17, the first surface side electrode 310 has an opening at a position corresponding to the phase modulation regions 304-1 to 304-15 and the second surface side electrodes 3081 to 308-15. It has 310-1 to 310-15. The first surface side electrode 310 may be a transparent electrode instead of the electrode having an opening.

The vertical relationship between the active layer 303 and the phase modulation layer 304 may be the reverse of the vertical relationship shown in FIG. Further, FIG. 17 also shows a common substrate layer 301, an upper optical guide layer 305b, a lower optical guide layer 305a, a contact layer 307, an insulating layer 309, and an antireflection layer 311. You don't have to have these.

The manufacturing method including the main steps excluding the manufacturing steps of each layer, the constituent material of each region, the shape, the dimensions, and the separation region described above are described in Patent Document 1 as in the first embodiment and the second embodiment. Those skilled in the art can appropriately select based on the description, and some examples are shown below. That is, an example of the material or structure of each layer shown in FIG. 17 is as follows. The common substrate layer 301 is made of GaAs. The first clad layer 302 is made of AlGaAs. The active layer 303 has a multiple quantum well structure MQW (barrier layer: AlGaAs / well layer: InGaAs). The phase modulation layer 304 includes a basic region 304-1a to 304-15a and a plurality of different refractive index regions 304-1b to 304-15 embedded in the basic regions 304-1a to 304-15a. The basic regions 304-1a to 304-15a are made of GaAs. A plurality of different refractive index regions 304-1b to 304-15b are made of AlGaAs. The upper optical guide layer 305b and the lower optical guide layer 305a are made of AlGaAs. The second clad layer 306 is made of AlGaAs. The contact layer 307 is made of GaAs. The insulating layer 309 is made of SiO ₂ or silicon nitride. The antireflection layer 311 is made of a dielectric single layer film such as silicon nitride (SiN) or silicon dioxide (SiO ₂ ) or a dielectric multilayer film. The separation region 312 is a semiconductor layer modified by high-intensity light (electric field), a semiconductor layer insulated by any of impurity diffusion and ion implantation methods, or slits (voids) formed by dry etching or wet etching. Is. Here, as a specific method of modification by high-intensity light (electric field), for example, there is processing by a nanosecond laser or processing by an ultra-short pulse laser. The plurality of different refractive index regions 304-1b to 304-15b may be pores in which argon, nitrogen, air, or the like is enclosed.

In one example, N-type impurities are added to the common substrate layer 301 and the first clad layer 302. P-type impurities are added to the second clad layer 306 and the contact layer 307. Further, the energy band gap between the first clad layer 302 and the second clad layer 306 is larger than the energy band gap between the upper optical guide layer 305b and the lower optical guide layer 305a. The energy bandgap between the upper optical guide layer 305b and the lower optical guide layer 305a is set to be larger than the energy bandgap of the multiple quantum well structure MQW of the active layer 303.

Next, the configuration of the light emitting device including the semiconductor light emitting device 300 will be described with reference to FIG. FIG. 18 is a block diagram showing a configuration of a light emitting device including a semiconductor light emitting device 300.

As shown in FIG. 18, the light emitting device 340 includes a semiconductor light emitting element 300, a power supply circuit 341, a control signal input circuit 342, and a drive circuit 343. The power supply circuit 341 supplies power to the drive circuit 343 and the semiconductor light emitting element 300. The control signal input circuit 342 transmits a control signal supplied from the outside of the light emitting device 340 to the drive circuit 343. The drive circuit 343 supplies a drive current to the semiconductor light emitting device 300. The drive circuit 343 and the semiconductor light emitting device 300 are connected to a plurality of drive lines 344-1 to 344-15 for supplying a drive current by one common potential line 345. The drive lines 344-1 to 344-15 are connected to the second surface side electrodes 308-1 to 308-15, respectively, and the common potential line 345 is connected to the first surface side electrode 310. In FIG. 18, the semiconductor light emitting element 300 shown above the drive circuit 343 and the semiconductor light emitting element 300 shown below the drive circuit 343 are the first surface and the second surface of one semiconductor light emitting element 300, respectively. Represents a face.

The drive lines 344-1 to 344-15 may be selectively driven or at least two may be driven at the same time depending on the application. Further, the drive circuit 343 may be configured separately from the semiconductor light emitting element 300, or may be integrally formed on the common substrate layer 301 of the semiconductor light emitting element 300.

The light emitting device 340 including the semiconductor light emitting device 300 configured as described above operates as follows. That is, a drive current is supplied from the drive circuit 343 between any of the drive lines 344-1 to 344-15 and the common potential line 345. In the light emitting portion corresponding to the second surface side electrode connected to the drive line to which the drive current is supplied, electrons and holes are recombined in the active layer 303, and the active layer 303 in the light emitting portion emits light. The light obtained by the light emission is efficiently confined by the first clad layer 302 and the second clad layer 306. The light emitted from the active layer 303 enters the inside of the corresponding phase modulation region and forms a predetermined mode by the confinement effect due to the two-dimensional feedback by the phase modulation region. By injecting sufficient electrons and holes into the active layer, the light incident on the phase modulation region oscillates in a predetermined mode. The light forming the predetermined oscillation mode undergoes phase modulation according to the arrangement pattern of the different refractive index region, and the light subjected to the phase modulation is the first light having a beam projection region and a beam projection pattern according to the arrangement pattern. It is emitted to the outside from the surface side electrode side.

Also in this embodiment, the semiconductor light emitting element 300 is a single element including a phase modulation layer 304 having a plurality of phase modulation regions 304-1 to 304-15. Therefore, unlike the configuration in which a plurality of semiconductor light emitting elements each having one phase modulation region (phase modulation layer) are arranged on the support substrate, a process in which the plurality of semiconductor light emitting elements are arranged on the support substrate is required. Is not considered. Therefore, it is possible to easily and highly accurately irradiate the target beam projection area with the light of the target beam projection pattern.

Also in this embodiment, the common substrate is applied to the active layer 303, the phase modulation layer 304, the first clad layer 302, the second clad layer 306, and the common substrate layer 301 from the second surface 300b toward the common substrate layer 301. A separation region 312 extending until it reaches layer 301 is provided. The adjacent phase modulation regions 304-1 to 304-15 are electrically and optically separated by such a separation region 312, so that crosstalk between the adjacent phase modulation regions 304-1 to 304-15 can occur. Occurrence is suppressed. As a result, irradiation of a desired beam projection region with light of a desired beam projection pattern is realized with even higher accuracy.

Also in this embodiment, the phase modulation regions 304-1 to 304-15 are arranged so that the beam projection regions are equal when the drive current is supplied from any of the second surface side electrodes 3081 to 308-15. The arrangement pattern in each may be defined. In the case of such a configuration, various applications other than the application example of the semiconductor light emitting device shown in Patent Document 1 (application example in which a laser beam is scanned against an object) are possible. Possible applications are similar to the second embodiment.

Further, also in the present embodiment, the phase modulation regions 304-1 to 304- are so that the beam projection pattern becomes the same when the drive current is supplied from any of the second surface side electrodes 308-1 to 308-15. The arrangement pattern in each of 15 may be set. In the case of such a configuration, the same application as the application example of the semiconductor light emitting device (application example in which the laser beam is scanned against the object) shown in Patent Document 1 is possible, and the application is different from that. Various applications are also possible. The possible applications in this case are the same as in the second embodiment.

(Fourth Embodiment)
The fourth embodiment is modified so that the light output taken out from the first surface side in the first embodiment is taken out from the second surface side. According to this, since the light output does not pass through the common substrate layer, it is possible to eliminate the absorption of the output light by the common substrate layer, and it is possible to prevent the attenuation of the output light and the heat generation of the common substrate layer. It is the same as the first embodiment except for the changes made in this way.

The configuration of the semiconductor light emitting device 100B according to the fourth embodiment will be described with reference to FIGS. 19 to 21. FIG. 19 is a view of the semiconductor light emitting device 100B according to the fourth embodiment as viewed from the first surface side. FIG. 20 is a view of the semiconductor light emitting device 100B as viewed from the second surface side. 21 is a cross-sectional view taken along the line XX-XX of FIGS. 19 and 20.

As shown in FIGS. 19 to 21, the semiconductor light emitting element 100B has a first surface 100Ba and a second surface 100Bb, and unlike the first to third embodiments, the semiconductor light emitting element 100B has a second surface as a light emitting surface. Light is output from 100Bb. In this embodiment, the first surface 100Ba functions as a support surface. The semiconductor light emitting device 100B includes a common substrate layer 101B, an active layer 103B, a phase modulation layer 104B, a first clad layer 102B, a second clad layer 106B, and a pair of second surface side electrodes 108B-1, 108B-. 2 and a pair of first surface side electrodes 110B-1 and 110B-2. The phase modulation layer 104B has a pair of phase modulation regions 104B-1 and 104B-2 that are optically coupled to the active layer 103B. At least, the laminated structure is composed of the active layer 103B and the phase modulation layer 104B including the pair of phase modulation regions 104B-1 and 104B-2. The first clad layer 102B is located on the side where the first surface 100Ba is arranged with respect to the laminated structure (including at least the active layer 103B and the phase modulation layer 104B). The second clad layer 106B is located on the side where the second surface 100Bb is arranged with respect to the laminated structure (including at least the active layer 103B and the phase modulation layer 104B). The second surface side electrodes 108B-1 and 108B-2 are on the side where the second surface 100Bb is arranged with respect to the second clad layer 106B, and are located at positions corresponding to the phase modulation regions 104B-1 and 104B-2, respectively. Is located in. The first surface side electrodes 110B-1 and 110B-2 are located on the side where the first surface 100Ba is arranged with respect to the first clad layer 102.

Each of the phase modulation regions 104B-1 and 104B-2 has the basic regions 104B-1a and 104B-1b having the first refractive index and the plurality of different refractive index regions 104B- having a second refractive index different from the first refractive index. It has 2a and 104B-2b. The plurality of different refractive index regions 104B-1b and 104B-2b are located where the center of gravity G1 is deviated from each grid point O in the virtual square grid in the basic regions 104B-1a and 104-2a by a predetermined distance r. It is arranged in the basic regions 104B-1a and 104B-2a according to the arrangement pattern such that it is located in. The arrangement pattern of the plurality of different refractive index regions 104B-1b and 104B-2b in each of the phase modulation regions 104B-1 and 104B-2 is the second surface side electrode 108B corresponding to the phase modulation region 104B-1 or 104B-2. The beam projection pattern represented by the light output from the second surface 100Bb when the drive current is supplied from -1 or 108B-2 and the beam projection region which is the projection range of the beam projection pattern are the target beam projection patterns. Is set to match the target beam projection area.

The light beam projection region output when the drive current is supplied from the second surface side electrode 108B-1 and the light beam projection region output when the drive current is supplied from the second surface side electrode 108B-2. May be the same or different. Further, the beam projection pattern of the light output when the drive current is supplied from the second surface side electrode 108B-1 and the beam projection output when the drive current is supplied from the second surface side electrode 108B-2. The patterns may be the same or different.

The active layer 103B, the phase modulation layer 104B, the first clad layer 102B, the second clad layer 106B, and the common substrate layer 101B reach the common substrate layer 101B from the second surface 100Bb toward the common substrate layer 101B. A separation region 112B extending to is provided. The separation region 112B overlaps with the phase modulation regions 104B-1 and 104B-2 when viewed from the Z-axis direction (stacking direction), the active layer 103B, the first clad layer 102B, the second clad layer 106B, and the first clad layer. It extends from the second surface 100Bb toward the common substrate layer 101B so as to electrically and optically separate the corresponding regions in each of the 102B and the second clad layer 106B. The thickness of the portion of the common substrate layer 101B located below the separation region 112B (first surface side electrode 110B-1, 110B-2 side end surface 112Ba and first surface side electrode 110B-1 of the separation region 112B, The distance between 110B-2) is less than half the thickness of the common substrate layer 101B along the Z-axis direction (stacking direction), and is typically 70 μm or less. In this fourth embodiment, the first surface side electrode is divided into two, but these two first surface side electrodes 110B-1 and 110B-2 are collectively referred to as "first surface side electrode". .. Therefore, "the distance between the end faces 112Ba on the first surface side electrodes 110B-1 and 110B-2 of the separation region 112B and the first surface side electrodes 110B-1 and 110B-2" (the separation region in the common substrate layer 101B). The thickness of the unformed portion) is one plane including the side surface on which the common substrate layer 101B is arranged, and the end surface of both the first surface side electrode 110B-1 and the first surface side electrode 110B-2. Refers to the distance from 112Ba. The distance (minimum spacing) from the end surface 112Ba of the separation region 112B defined in this way to the first surface side electrodes 110B-1 and 110B-2, and the thickness of the common substrate layer 101B along the Z-axis direction (stacking direction). It is less than half of. Further, the thickness of the unformed portion of such a separation region is typically 70 μm or less. As shown in FIG. 21, each portion of the semiconductor light emitting element 100B separated at the position of the separation region 112B can be regarded as an independent light emitting unit (first light emitting unit, second light emitting unit). Further, the manufacturing process of the separation region 112B is the same as that of the first embodiment.

The second surface side electrodes 108B-1 and 108B-2 are connected to the phase modulation regions 104B-1 and 104B-2 and the first surface side electrodes 110B-1 and 110B-2 as shown in FIGS. 20 and 21. It has openings 108B-1a and 108B-2a at corresponding positions. The second surface side electrodes 108B-1 and 108B-2 may be transparent electrodes instead of the electrodes having openings.

The vertical relationship between the active layer 103B and the phase modulation layer 104B may be the reverse of the vertical relationship shown in FIG. Further, the DBR layer 120B may be provided between the common substrate layer 101B and the first clad layer 102B for the purpose of reducing the absorption of light in the common substrate layer 101B. The DBR layer 120B may be located at any other location as long as it is between the phase modulation layer 104B and the common substrate layer 101B. Further, although the common substrate layer 101B, the upper optical guide layer 105Bb, the lower optical guide layer 105Ba, the contact layer 107B, the insulating layer 109, and the antireflection layer 111B are also shown in FIG. 21, the semiconductor light emitting element 100B is not always the same. You don't have to have these.

A person skilled in the art can appropriately select the manufacturing method including the main steps excluding the manufacturing steps of each layer, each region, the shape, the dimensions, and the separation region described above, based on the contents described in Patent Document 1. However, some examples are shown below. That is, an example of the material or structure of each layer shown in FIG. 21 is as follows. The common substrate layer 101B is made of GaAs. The first clad layer 102B is made of AlGaAs. The active layer 103B has a multiple quantum well structure MQW (barrier layer: AlGaAs / well layer: InGaAs). The phase modulation layer 104B includes a basic region 104B-1a, 104B-2a and a plurality of different refractive index regions 104B-1b, 104B-2b embedded in the basic regions 104B-1a, 104B-2a. The basic regions 104B-1a and 104B-2a are made of GaAs. The plurality of different refractive index regions 104B-1b and 104B-2b are made of AlGaAs. The upper optical guide layer 105Bb and the lower optical guide layer 105Ba are made of AlGaAs. The second clad layer 106B is made of AlGaAs. The contact layer 107B is made of GaAs. The insulating layer 109B is made of SiO ₂ or silicon nitride. The antireflection layer 111B is made of a dielectric single layer film such as silicon nitride (SiN) or silicon dioxide (SiO ₂ ) or a dielectric multilayer film. The separation region 112B was formed by a semiconductor layer modified by high-intensity light (electric field), a semiconductor layer insulated by any of impurity diffusion and ion implantation methods, or by either dry etching or wet etching. It is a slit (gap). Here, as a specific method of modification by high-intensity light (electric field), for example, there is processing by a nanosecond laser or processing by an ultrashort pulse laser. The plurality of different refractive index regions 104B-1b and 104B-2b may be pores in which argon, nitrogen, air, or the like is enclosed.

In one example, N-type impurities are added to the common substrate layer 101B and the first clad layer 102B. P-type impurities are added to the second clad layer 106B and the contact layer 107B. Further, the energy band gap between the first clad layer 102B and the second clad layer 106B is larger than the energy band gap between the upper optical guide layer 105Bb and the lower optical guide layer 105Ba. The energy bandgap between the upper optical guide layer 105Bb and the lower optical guide layer 105Ba is set to be larger than the energy bandgap of the multiple quantum well structure MQW of the active layer 103B.

Although the first to fourth embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned first to fourth embodiments.

For example, in the first to fourth embodiments, the separation regions 112, 212, 312, 112B are provided, but when the interval between adjacent phase modulation regions can be widened, crosstalk does not become a problem. Does not have to have a separation region.

For example, FIGS. 4 and 5 show an example in which the different refractive index region is circular (perfect circle), but the different refractive index region may have a shape other than circular. For example, when the shape of a plurality of different refractive index regions on the XY plane is any of a perfect circle, a square, a regular hexagon, a regular octagon, a regular hexagon, a rectangle, and an ellipse, that is, each different refractive index. When the shape of the region is mirror image symmetry (line symmetry), in the phase modulation layer, the center of gravity of each corresponding different refractive index region from the grid point O of each of the plurality of unit constituent regions R constituting a virtual square grid. It is possible to set the angle φ formed by the direction toward G1 and the s axis parallel to the X axis with high accuracy. Further, the shapes of the plurality of different refractive index regions on the XY plane are shapes that do not have 180 ° rotational symmetry as shown in FIGS. 22 (a) to 22 (j). May be good. Shapes that do not have 180 ° rotational symmetry include, for example, the regular triangle shown in FIG. 22 (b), the right-angled isosceles triangle shown in FIG. 22 (a), and FIG. 22 (c). Isosceles triangle, the shape shown in FIG. 22 (i), the oval shape shown in FIG. 22 (h), and the tear-shaped shape shown in FIG. 22 (d), in which parts of two circles or ellipses overlap. , The arrow-shaped shape shown in FIG. 22 (e), the trapezoidal shape shown in FIG. 22 (f), the pentagon shown in FIG. The shape shown in is included. In this case, it becomes possible to obtain a higher light output. As shown in FIG. 22 (h), the oval shape has a dimension in the minor axis direction in the vicinity of one end along the major axis and a dimension in the minor axis direction in the vicinity of the other end. It is a shape obtained by deforming an ellipse so that it becomes smaller than. The teardrop shape is a shape obtained by transforming one end of an ellipse along its long axis into a pointed end that protrudes along the long axis, as shown in FIG. 22 (d). Is. As shown in FIG. 22 (e), the arrow-shaped shape is such that one side of the rectangle forms a triangular notch, while the side facing the one side forms a triangular protrusion.

Further, in each of the first to third embodiments, the semiconductor light emitting element outputs light from the first surface, but as in the fourth embodiment, the second surface side electrode is an electrode having an opening or transparent. By using it as an electrode, it may be a semiconductor light emitting element that outputs light from the second surface side. In the fourth embodiment, the number of the phase modulation region, the second surface side electrode, and the first surface side electrode is two (pair) each, but as in the second and third embodiments, they are three. One or more may be arranged in one dimension or two dimensions. In the case of a semiconductor light emitting element that outputs light from the second surface side, since the light output does not pass through the common substrate layer, it is possible to eliminate the absorption of output light by the common substrate layer, and the attenuation of output light and the common substrate can be eliminated. It is possible to prevent the layer from generating heat.

As in the first modification shown in FIG. 23, the phase modulation layer includes an inner region A including a beam projection region and a plurality of different refractive index regions for generating a beam projection pattern, and the inner region A. An outer region B surrounding the outer periphery may be provided. The inner region A is substantially a region composed of a unit constituent region R in which corresponding different refractive index regions are arranged. The outer region B is provided with a plurality of peripheral grid point different refractive index regions, and the center of gravity of the plurality of peripheral grid point different refractive index regions is, for example, the virtual square on the outer periphery of the virtual square grid. It suffices to match the grid points in the extended square grid defined by setting the same grid structure as the grid. Note that FIG. 23 shows a modified example of the phase modulation layer as viewed along the layer thickness direction (Z-axis direction). In FIG. 23, the outer contour (outer region B) represents a part of the phase modulation region. The inner region A surrounded by the outer region B is a phase modulation region (substantially similar to the first to fourth embodiments) including a beam projection region and a plurality of different refractive index regions for generating a beam projection pattern. A region composed of a plurality of unit configuration regions R). Therefore, in the example of FIG. 23, the phase modulation region of the phase modulation layer is composed of an inner region A and an outer region B. As described above, the outer region B is a region including a plurality of peripheral lattice point different refractive index regions having a center of gravity at the lattice point position in the virtual square lattice, and an example thereof is shown below. That is, the lattice constant of the virtual square lattice in the outer region B is equal to the lattice constant of the virtual square lattice in the inner region A, and the shape and size of each peripheral lattice point different refractive index region in the outer region B are inside. It may be equal to the shape and size of the different refractive index region in the region A. According to this modification, light leakage in the in-plane direction is suppressed, and the oscillation threshold current can be reduced.

Further, in FIGS. 4 and 5, a different refractive index region having a center of gravity G1 at a position deviated by a predetermined distance from each grid point in a virtual square lattice in the basic region (hereinafter, “displacement different refractive index region”” is shown. However, an example was shown in which one is provided in each unit constituent area. However, the displacement different refractive index region may be divided into a plurality of portions so that the entire center of gravity is located at a position deviated by a predetermined distance from each of the above grid points. Further, in addition to the displacement different refractive index region, a grid point different refractive index region may be provided on each grid point. The lattice point different refractive index region is a region having a refractive index different from the refractive index (first refractive index) of the basic region as in the displaced different refractive index region, but is the same material as the displaced different refractive index region (same refraction). It may be composed of a material of rate), or a part thereof may overlap with a part of the displacement different refractive index region.

Here, with reference to FIGS. 24 to 26, an example in which a lattice point different refractive index region is provided in addition to the displacement different refractive index region will be described. FIG. 24 is a diagram for explaining the positional relationship between the center of gravity of the displacement different refractive index region and the lattice point different refractive index region when the lattice point different refractive index region is provided in addition to the displacement different refractive index region. FIG. 25 is a diagram showing an example (rotation method) of a combination of the displacement different refractive index region and the lattice point refractive index region when the lattice point different refractive index region is provided in addition to the displacement different refractive index region. FIG. 26 is a diagram showing a modified example (rotation method) in which a lattice point different refractive index region is provided in addition to the displaced different refractive index region.

In these figures, O represents a grid point, G1 represents the center of gravity of the displaced refractive index region, and G2 represents the center of gravity of the grid point different refractive index region. As shown in FIG. 24, the positional relationship between the center of gravity G1 of the displacement different refractive index region n04-mb and the lattice point O is the same as that in FIG. n04-mc is provided. In FIG. 24, the center of gravity G2 of the lattice point different refractive index region n04-mc overlaps with the lattice point O, but as shown in FIG. 26, the center of gravity G2 does not necessarily have to be above the lattice point O. .. In FIG. 24, the displacement different refractive index region n04-mb and the lattice point different refractive index region n04-mc are both circular and do not overlap each other, but the combination of the two is not limited to this.

As shown in FIG. 25, various combinations can be considered as the combination of the displacement different refractive index region n04-mb and the lattice point different refractive index region n04-mc. 25 (a) is the combination of FIG. 24. In FIG. 25B, the displacement different refractive index region n04-mb and the lattice point different refractive index region n04-mc are both a combination of squares. FIG. 25 (c) shows a combination in which the displacement different refractive index region n04-mb and the lattice point different refractive index region n04-mc are both circular, but a part of both is overlapped with each other. FIG. 25 (d) shows a combination in which the displacement different refractive index region n04-mb and the lattice point different refractive index region n04-mc are both square, and a part of both is overlapped with each other. In FIG. 25 (e), the displacement different refractive index region n04-mb and the lattice point different refractive index region n04-mc in FIG. 25 (d) are arbitrarily rotated around their respective centers of gravity G1 and G2 (lattice point O). It is a combination in which the two do not overlap each other. In FIG. 25 (f), the displacement different refractive index region n04-mb is a triangle, and the lattice point different refractive index region n04-mc is a square combination. In FIG. 25 (g), the displacement different refractive index region n04-mb and the lattice point different refractive index region n04-mc in FIG. 25 (f) are arbitrarily rotated around their respective centers of gravity G1 and G2 (lattice point O). It is a combination in which the two do not overlap each other. FIG. 25 (h) is a combination in which the displacement different refractive index region n04-mb of FIG. 25 (a) is divided into two circular regions. FIG. 25 (i) shows a combination in which the displacement different refractive index region n04-mb is divided into a square and a triangle, and the lattice point different refractive index region n04-mc is a triangle. In FIG. 25 (j), the displacement different refractive index region n04-mb and the lattice point different refractive index region n04-mc in FIG. 25 (i) are arbitrarily rotated around their respective centers of gravity G1 and G2 (lattice point O). It is a combination of refraction. In FIG. 25 (k), the displacement different refractive index region n04-mb and the lattice point different refractive index region n04-mc are both squares, and the displacement different refractive index region n04-mb is divided into two squares, each square. It is a combination in which the directions of the sides are the same. When a lattice point different refractive index region is provided in addition to the displacement different refractive index region, the entire different refractive index region including both of them does not have 180 ° rotational symmetry, so that a higher light output can be obtained. Can be done.

When the shape of the different refractive index region (including the peripheral lattice point different refractive index region and the lattice point different refractive index region) has a linear side, the direction of the side is set to the common substrate layer. It is desirable to align the constituent crystals with a specific plane orientation. By doing so, when the different refractive index region is a hole filled with argon, nitrogen, air, etc., the shape of the hole can be easily controlled, and defects in the crystal layer grown on the hole can be suppressed. can do.

The shape and number of different refractive index regions (including peripheral grid point different refractive index regions and grid point different refractive index regions) provided corresponding to each grid point are not necessarily the same within one phase modulation region. No need. As shown in FIG. 27 (second modification of the phase modulation layer n04-m shown in FIG. 4), the shape and number of the different refractive index regions may be different for each lattice point.

Next, a case where the arrangement pattern of the different refractive index region n04-mb in the phase modulation layer n04-m is determined by the axial shift method will be described. Even when the on-axis shift method is applied instead of the above-mentioned rotation method as the method for determining the arrangement pattern of the different refractive index region n04-mb in the phase modulation layer n04-m, the obtained phase modulation layer is described above. It is applied to the semiconductor light emitting module according to various embodiments.

FIG. 28 is a schematic diagram for explaining an arrangement pattern (on-axis shift method) of the different refractive index region n04-mb in the phase modulation layer n04-m. The phase modulation layer n04-m includes a basic region n04-ma of the first refractive index and a different refractive index region n04-mb having a second refractive index different from the first refractive index. Here, a virtual square lattice defined on the XY plane is set in the phase modulation layer n04-m, as in the example of FIG. One side of the square grid is parallel to the X-axis and the other side is parallel to the Y-axis. At this time, the square-shaped unit constituent region R centered on the grid point O of the square grid extends over a plurality of columns (x1 to x4) along the X axis and a plurality of rows (y1 to y3) along the Y axis. It is set in two dimensions. Assuming that the coordinates of each unit constituent area R are given at the position of the center of gravity of each unit constituent area R, this center of gravity position coincides with the grid point O of the virtual square grid. A plurality of different refractive index regions n04-mb are provided one by one in each unit constituent region R. The planar shape of the different refractive index region n04-mb is, for example, a circular shape. The lattice point O may be located outside the different refractive index region n04-mb, or may be included inside the different refractive index region n04-mb.

The ratio of the area S of the different refractive index region n04-mb in one unit constituent region R is referred to as a filling factor (FF). Assuming that the grid spacing of the square lattice is a, the filling factor FF of the different refractive index region n04-mb is given as S / a ² . S is the area of the different refractive index region n04-mb in the XY plane, and when the shape of the different refractive index region n04-mb is, for example, a perfect circle, S = π (D / 2) using the diameter D of the perfect circle. ) Given as ² . Further, when the shape of the different refractive index region n04-mb is square, it is given as S = LA ² using the length LA of one side of the square.

FIG. 29 is an example of an arrangement pattern determined by the axis shift method, in order to explain the positional relationship between the center of gravity G1 in the different refractive index region n04-mb and the lattice point O (x, y) in a virtual square grid. It is a figure of. As shown in FIG. 29, the center of gravity G1 of each different refractive index region n04-mb is arranged on the straight line L. The straight line L is a straight line that passes through the corresponding grid points O (x, y) of the unit constituent region R (x, y) and is inclined with respect to each side of the square grid. In other words, the straight line L is a straight line inclined with respect to both the s-axis and the t-axis that define the unit constituent area R (x, y). The inclination angle of the straight line L with respect to the s axis is θ. The inclination angle θ is constant in the phase modulation layer n04-m. The inclination angle θ satisfies 0 ° <θ <90 °, and in one example, θ = 45 °. Alternatively, the inclination angle θ satisfies 180 ° <θ <270 °, and in one example, θ = 225 °. If the tilt angle θ satisfies 0 ° <θ <90 ° or 180 ° <θ <270 °, the straight line L extends from the first quadrant to the third quadrant of the coordinate plane defined by the s and t axes. .. Alternatively, the inclination angle θ satisfies 90 ° <θ <180 °, and in one example, θ = 135 °. Alternatively, the inclination angle θ satisfies 270 ° <θ <360 °, and in one example, θ = 315 °. When the tilt angle θ satisfies 90 ° <θ <180 ° or 270 ° <θ <360 °, the straight line L extends from the second quadrant to the fourth quadrant of the coordinate plane defined by the s-axis and the t-axis. Thus, the tilt angle θ is an angle excluding 0 °, 90 °, 180 ° and 270 °. Here, let r (x, y) be the distance between the grid point O (x, y) and the center of gravity G1. x indicates the position of the x-th grid point on the X-axis, and y indicates the position of the y-th grid point on the Y-axis. When the distance r (x, y) is a positive value, the center of gravity G1 is located in the first quadrant (or the second quadrant). When the distance r (x, y) is a negative value, the center of gravity G1 is located in the third quadrant (or the fourth quadrant). When the distance r (x, y) is 0, the grid point O and the center of gravity G1 coincide with each other.

なお、目標ビーム投射パターンから複素振幅分布を求める際には、ホログラム生成の計算時に一般的に用いられるGerchberg-Saxton（ＧＳ）法のような繰り返しアルゴリズムを適用することによって、ビーム投射パターンの再現性が向上する。The distance r (x, y) between the center of gravity G1 of each different refractive index region n04-mb and the corresponding lattice point O (x, y) of the unit constituent region R (x, y) shown in FIG. 28 is , Each different refractive index region n04-mb is set individually according to the target beam projection pattern (optical image). The distribution of the distance r (x, y) has a specific value for each position determined by the values of x (x1 to x4 in the example of FIG. 28) and y (y1 to y3 in the example of FIG. 28), but is not necessarily specific. It is not always represented by the function of. The distribution of the distance r (x, y) is determined from the complex amplitude distribution obtained by inverse Fourier transforming the target beam projection pattern from which the phase distribution is extracted. That is, when the phase P (x, y) in the unit constituent region R (x, y) shown in FIG. 29 is P ₀ , the distance r (x, y) is set to 0, and the phase P ( When x, y) is π + P ₀ , the distance r (x, y) is set to the maximum value R ₀ , and when the phase P (x, y) is −π + P ₀ , the distance r (x, y) is set. ) Is set to the minimum value -R ₀ . Then, for the intermediate phase P (x, y), the distance r (x, y) is such that r (x, y) = {P (x, y) −P ₀ } × R ₀ / π. ) Is set. Here, the initial phase P ₀ can be set arbitrarily. Assuming that the grid spacing of the square lattice is a, the maximum value R ₀ of r (x, y) is, for example, in the range of the following equation (10).

When calculating the complex amplitude distribution from the target beam projection pattern, the reproducibility of the beam projection pattern is applied by applying an iterative algorithm such as the Gerchberg-Saxton (GS) method that is generally used when calculating hologram generation. Is improved.

FIG. 30 is a plan view showing an example in which the refractive index substantially periodic structure is applied only within a specific region of the phase modulation layer as a first modification of the phase modulation layer of FIG. 28. In the example shown in FIG. 30, similarly to the example shown in FIG. 23, a substantially periodic structure for emitting a target beam projection pattern inside the inner region RIN of the square (example: the structure of FIG. 28). ) Is formed. On the other hand, in the outer region ROUT surrounding the inner region RIN, a perfect circular different refractive index region having the same center of gravity position is arranged at the grid point position of the square lattice. In the inner region RIN and the outer region ROUT, the grid spacing of the square grids virtually set is the same (= a). In the case of this structure, since the light is also distributed in the outer region ROUT, it is possible to suppress the generation of high-frequency noise (so-called window function noise) generated by the sudden change in light intensity in the peripheral portion of the inner region RIN. can. In addition, light leakage in the in-plane direction can be suppressed, and a reduction in the threshold current can be expected.

The optical image obtained as a beam projection pattern output from each of the plurality of semiconductor light emitting elements in the semiconductor light emitting module according to the above-mentioned various embodiments, and the phase distribution P (x, y) in the phase modulation layer n04-m. The relationship is the same as in the case of the above-mentioned rotation method (FIG. 5). Therefore, the first precondition that defines the square grid, the second precondition that is defined by the above equations (1) to (3), and the above-mentioned first precondition that is defined by the above equations (4) and (5). Under the precondition of 3, and the fourth precondition defined by the above equations (6) and (7), the phase modulation layer n04-m is configured to satisfy the following conditions. That is, the distance r (x, y) from the lattice point O (x, y) to the center of gravity G of the corresponding different refractive index region n04-mb is.
r (x, y) = C × (P (x, y) -P ₀ )
C: Proportional constant, for example R ₀ / π
P ₀ : An arbitrary constant, for example, 0
The corresponding different refractive index regions n04-mb are arranged in the unit constituent region R (x, y) so as to satisfy the above relationship. That is, the distance r (x, y) is set to 0 when the phase P (x, y) in the unit constituent region R (x, y) is P ₀ , and the phase P (x, y) is π + P. When it is ₀ , it is set to the maximum value R ₀ , and when the phase P (x, y) is −π + P ₀ , it is set to the minimum value −R ₀ . When it is desired to obtain a target beam projection pattern, the target beam projection pattern is subjected to an inverse Fourier transform, and the distribution of the distance r (x, y) corresponding to the phase P (x, y) of the complex amplitude is obtained by a plurality of different refractive indexes. It is preferable to give it to the rate region n04-mb. The phase P (x, y) and the distance r (x, y) may be proportional to each other.

The far-field image after Fourier conversion of the laser beam has various shapes such as a single spot shape, a ring shape, a linear shape, a character shape, a double ring shape, or a Lager Gaussian beam shape. Can be taken. Since the beam direction can also be controlled, for example, a laser that electrically performs high-speed scanning by arranging each of a plurality of semiconductor light emitting elements in the semiconductor light emitting module according to the above-mentioned various embodiments in a one-dimensional or two-dimensional array. A processing machine can be realized. Since the beam projection pattern is represented by angle information in the distant field, if the target beam projection pattern is a bitmap image represented by two-dimensional position information, it is temporarily converted into angle information. Then, after converting to the wave number space, it is advisable to perform the reciprocal Fourier transform.

As a method of obtaining the intensity distribution and the phase distribution from the complex amplitude distribution obtained by the inverse Fourier transform, for example, the intensity distribution I (x, y) is calculated by using the abs function of the numerical analysis software "MATLAB" of MathWorks. The phase distribution P (x, y) can be calculated by using the MATLAB angle function.

Here, when the phase distribution P (x, y) is obtained from the inverse Fourier conversion result of the target beam projection pattern and the distance r (x, y) of each different refractive index region n04-mb is determined, general discrete Fourier is used. Here are some points to keep in mind when calculating using transformation (or high-speed Fourier transformation). Note that FIG. 31 is a diagram for explaining the points to be noted when determining the arrangement of the different refractive index region by obtaining the phase angle distribution (corresponding to the rotation angle distribution in the rotation method) from the inverse Fourier conversion result of the target beam projection pattern. .. The beam projection pattern calculated from the complex amplitude distribution obtained by the inverse Fourier transform of FIG. 31 (a), which is the target beam projection pattern, is in the state shown in FIG. 31 (b). When divided into four quadrants such as A1, A2, A3, and A4, respectively, as shown in FIGS. 31 (a) and 31 (b), the first quadrant of the beam projection pattern of FIG. 31 (b) is shown in FIG. 31. A superposed pattern in which the pattern rotated by 180 degrees in the first quadrant of (a) and the pattern in the third quadrant of FIG. 31 (a) are superimposed appears. In the second quadrant of FIG. 31 (b), a superimposed pattern in which the pattern rotated by 180 degrees in the second quadrant of FIG. 31 (a) and the pattern of the fourth quadrant of FIG. 31 (a) are superimposed appears. In the third quadrant of FIG. 31 (b), a superimposed pattern in which the pattern rotated by 180 degrees in the third quadrant of FIG. 31 (a) and the pattern of the first quadrant of FIG. 31 (a) are superimposed appears. In the fourth quadrant of FIG. 31 (b), a superimposed pattern in which the pattern rotated by 180 degrees in the fourth quadrant of FIG. 31 (a) and the pattern of the second quadrant of FIG. 31 (a) are superimposed appears. At this time, the pattern rotated by 180 degrees is a pattern due to the -1st order light component.

Therefore, when a pattern having a value only in the first quadrant is used as the light image (original light image) before the inverse Fourier transformation, the first quadrant of the original light image is used in the third quadrant of the obtained beam projection pattern. Appears, and a pattern obtained by rotating the first quadrant of the original light image by 180 degrees appears in the first quadrant of the obtained beam projection pattern.

In the above-mentioned structure, the material system, the film thickness, and the structure of the layer can be variously changed as long as the structure includes the active layer and the phase modulation layer. Here, the scaling law holds for the so-called square lattice photonic crystal laser when the perturbation from the virtual square lattice is 0. That is, when the wavelength becomes a constant α times, the same standing wave state can be obtained by multiplying the entire cubic lattice structure by α. Similarly, also in the present embodiment, it is possible to determine the structure of the phase modulation layer n04-m by the scaling law according to the wavelength. Therefore, it is also possible to realize a semiconductor light emitting element that outputs visible light by using an active layer 12 that emits light such as blue, green, or red and applying a scaling rule according to a wavelength.

In the case of a square lattice with a lattice spacing a, if the unit vectors of Cartesian coordinates are x and y, the basic translation vector a ₁ = ax, a ₂ = ay, and the basic reciprocal lattice vector with respect to the translation vectors a ₁ and a ₂ . b ₁ = (2π / a) x, b ₂ = (2π / a) y. When the wave number vector of the wave existing in the lattice is k = nb ₁ + mb ₂ (n and m are arbitrary integers), the wave number k exists at the Γ point, but the magnitude of the wave number vector is basically the opposite. When it is equal to the magnitude of the lattice vector, a resonance mode (standing wave in the XY plane) in which the lattice spacing a is equal to the wavelength λ is obtained. In the various embodiments described above, oscillation in such a resonance mode (stationary wave state) can be obtained. At this time, considering the TE mode in which an electric field exists in a plane parallel to the square lattice, there are four modes in the standing wave state in which the lattice spacing and the wavelength are equal in this way due to the symmetry of the square lattice. In the various embodiments described above, a desired beam projection pattern can be similarly obtained when oscillating in any of the four standing wave modes.

The standing wave in the above-mentioned phase modulation layer n04-m is scattered by the hole shape, and the wave surface obtained in the direction perpendicular to the plane is phase-modulated to obtain a desired beam projection pattern. Therefore, a desired beam projection pattern can be obtained without a polarizing plate. This beam projection pattern is not only a pair of single peak beams (spots), but as described above, the character shape, two or more spots having the same shape, or the phase and intensity distribution are spatially non-uniform. It is also possible to use a vector beam or the like.

As an example, it is preferable that the refractive index of the basic region n04-ma is 3.0 to 3.5 and the refractive index of the different refractive index region n04-mb is 1.0 to 3.4. Further, the average radius of each different refractive index region n04-mb in the hole of the basic region n04-ma is, for example, 20 nm to 120 nm in the case of the 940 nm band. The diffraction intensity in the Z-axis direction changes as the size of each different refractive index region n04-mb changes. This diffraction efficiency is proportional to the optical coupling coefficient κ1 represented by the first-order coefficient when the shape of the different refractive index region n04-mb is Fourier transformed. The photocoupling coefficient is described in, for example, Non-Patent Document 2 above.

The effect obtained by the semiconductor light emitting device provided with the phase modulation layer n04-m in which the arrangement pattern of the different refractive index region n04-mb is determined in the axial shift method as described above will be described. Conventionally, as a semiconductor light emitting element, the center of gravity G1 of each different refractive index region n04-mb is arranged away from the corresponding lattice point O of the virtual square lattice, and corresponds to an optical image around each lattice point O. Those having a different rotation angle are known (see, for example, Patent Document 1). However, if it is possible to realize a new light emitting device in which the positional relationship between the center of gravity G1 of each different refractive index region n04-mb and each lattice point O is different from the conventional one, the range of design of the phase modulation layer n04-m will be expanded, which is extremely useful. be.

The phase modulation layer n04-m optically coupled to the active layer has a basic region n04-ma and a plurality of different refractive index regions n04-mb having a refractive index different from that of the basic region n04-ma, respectively. In the unit constituent region R defined by the orthogonal coordinate system of the axis and the t-axis, each is different on the straight line L that passes through the grid point O of the virtual square grid and is inclined with respect to both the s-axis and the t-axis. The center of gravity G1 in the refractive index region n04-mb is arranged. The distance r (x, y) between the center of gravity G1 of each different refractive index region n04-mb and the corresponding lattice point O is individually set according to the target beam projection pattern. In such a case, the phase of the beam changes according to the distance between the grid point O and the center of gravity G1. That is, the phase of the beam emitted from each different refractive index region n04-mb can be controlled only by changing the position of the center of gravity G1, and the beam projection pattern formed as a whole can be formed into a desired shape (target beam projection). It can be a pattern). That is, each of the above-mentioned semiconductor light emitting elements is an S-iPM laser, and according to such a structure, the center of gravity G1 of each different refractive index region n04-mb rotates around each lattice point O according to the target beam projection pattern. Similar to the conventional structure having an angle, it is possible to output a beam projection pattern having an arbitrary shape in a direction inclined with respect to a direction perpendicular to the first surface from which anger is output. As described above, in the on-axis shift method, it is possible to provide a semiconductor light emitting device and a semiconductor light emitting module in which the positional relationship between the center of gravity G1 of each different refractive index region n04-mb and each lattice point O is completely different from the conventional one.

Here, FIG. 32A is a diagram showing an example of a beam projection pattern (light image) output from the semiconductor light emitting device. The center of FIG. 32 (a) intersects the light emitting surface of the semiconductor light emitting device and corresponds to the axis perpendicular to the light emitting surface. Further, FIG. 32 (b) is a graph showing a light intensity distribution in a cross section including an axis perpendicular to the light emitting surface intersecting the light emitting surface of the semiconductor light emitting device. FIG. 32 (b) is a far-field image acquired using an FFP optical system (A3267-12 manufactured by Hamamatsu Photonics), a camera (ORCA-05G manufactured by Hamamatsu Photonics), and a beam profiler (Lepas-12 manufactured by Hamamatsu Photonics). The vertical counts of the image data of dots × 1024 dots are integrated and plotted. The maximum count number in FIG. 32 (a) is standardized by 255, and the central 0th-order light B0 is saturated in order to clearly indicate the intensity ratio of ± 1st-order light. From FIG. 32 (b), the difference in intensity between the primary light and the -1st order light can be easily understood. Further, FIG. 33 (a) is a diagram showing a phase distribution corresponding to the beam projection pattern shown in FIG. 32 (a). 33 (b) is a partially enlarged view of FIG. 33 (a). In FIGS. 33 (a) and 33 (b), the phase at each location in the phase modulation layer n04-m is indicated by shading, and the dark part has a phase angle of 0 ° and the bright part has a phase angle of 360 °. Get closer. However, since the center value of the phase angle can be set arbitrarily, the phase angle does not necessarily have to be set within the range of 0 ° to 360 °. As shown in FIGS. 32 (a) and 32 (b), the semiconductor light emitting device includes primary light including a first light image portion B1 that is output in a first direction inclined with respect to the axis. It is output in the second direction that is symmetric with respect to the first direction with respect to the axis, and outputs -1st order light including the first light image portion B1 and the second light image portion B2 that is rotationally symmetric with respect to the axis. Typically, the first light image portion B1 appears in the first quadrant in the XY plane and the second light image portion B2 appears in the third quadrant in the XY plane. However, depending on the application, only the primary light may be used and the -1st order light may not be used. In such a case, it is desirable that the amount of -1st order light is suppressed to be smaller than that of the primary light.

FIG. 34 is a diagram conceptually showing an example of a beam projection pattern of a traveling wave in each direction. In this example, in the unit constituent region R, the inclination angle of the straight line L with respect to the s-axis and the t-axis is set to 45 °. In the phase modulation layer of the square grid S-iPM laser, the basic traveling waves AU, AD, AR, and AL along the XY plane are generated. The traveling waves AU and AD are light traveling along the side extending in the Y-axis direction among each side of the square grid. The traveling wave AU travels in the positive direction on the Y axis, and the traveling wave AD travels in the negative direction on the Y axis. Further, the traveling waves AR and AL are light traveling along the side extending in the X-axis direction of each side of the square lattice. The traveling wave AR travels in the positive direction on the X-axis, and the traveling wave AL travels in the negative direction on the X-axis. In this case, beam projection patterns in opposite directions can be obtained from the traveling waves traveling in opposite directions. For example, a beam projection pattern BU containing only the second light image portion B2 can be obtained from the traveling wave AU, and a beam projection pattern BD containing only the first light image portion B1 can be obtained from the traveling wave AD. Similarly, the beam projection pattern BR containing only the second light image portion B2 is obtained from the traveling wave AR, and the beam projection pattern BL containing only the first light image portion B1 is obtained from the traveling wave AL. In other words, in the progressive waves traveling in opposite directions, one becomes the primary light and the other becomes the -1st order light. The beam projection pattern output from the semiconductor light emitting element is a combination of these beam projection patterns BU, BD, BR, and BL.

According to the study by the present inventors, in a conventional semiconductor light emitting device that rotates a different refractive index region around a grid point, both traveling waves traveling in opposite directions due to the nature of the arrangement of the different refractive index region are present. Must be included. That is, in the conventional method, in all of the four traveling waves AU, AD, AR, and AL forming the standing wave, the same amount of the primary light and the -1st order light appear, and the radius of the rotating circle ( Depending on the distance between the center of gravity of the different refractive index region and the lattice point), 0th-order light is generated. Therefore, it is difficult in principle to give a difference in the amount of each of the primary light and the -1st order light, and it is difficult to selectively reduce one of them. Therefore, it is difficult to reduce the amount of -1st-order light relative to the amount of primary light.

このとき、位相分布Φ（ｘ，ｙ）の０次光成分はＪ₀（２πｒ／ａ）、１次光成分はＪ₁（２πｒ／ａ）、－１次光成分はＪ_-1（２πｒ／ａ）と表される。ところで、±１次のベッセル関数に関しては、Ｊ₁（ｘ）＝－Ｊ_-1（ｘ）の関係があるため、±１次光成分の大きさは等しくなる。ここでは、４つの進行波の１例としてＹ軸正方向の進行波ＡＵについて考えたが、他の３波（進行波ＡＤ，ＡＲ，ＡＬ）についても同様の関係が成立し、±１次光成分の大きさが等しくなる。以上の議論から、異屈折率領域ｎ０４－ｍｂを格子点Ｏの周りで回転させる従来の方式では、±１次光成分の光量に差を与えることが原理的に困難となる。Here, FIG. 35 shows, as a method for determining the arrangement pattern of the above-mentioned different refraction rate region n04-mb, a rotation method for rotating the different refraction rate region around a grid point and traveling waves AU, AD, AR, AL. It is a figure which shows. The reason why it is difficult to selectively reduce either the primary light or the -1st order light in the rotation method in which the different refractive index region n04-mb is rotated around the lattice point O will be described. Consider a traveling wave AU in the positive direction of the t-axis shown in FIG. 35 (b) as an example of four traveling waves with respect to the design phase φ (x, y) at a certain position. At this time, due to the geometrical relationship, the deviation from the lattice point O is r · sinφ (x, y) for the traveling wave AU, so the phase difference is (2π / a) r · sinφ (x). , Y). As a result, the phase distribution Φ (x, y) with respect to the traveling wave AU has a small influence on the size of the different refractive index region n04-mb, and if the influence can be ignored, Φ (x, y) = exp { It is given by j (2π / a) r · sinφ (x, y)}. The contribution of this phase distribution Φ (x, y) to the 0th-order light and the ± 1st-order light is n = 0 and n = ± when expanded by exp {jnΦ (x, y)} (n: integer). It is given by one component. By the way, by using the mathematical formula defined by the following equation (11) for the first-class Vessel function Jn (z) of order n, the phase distribution Φ (x, y) can be expanded in series, and the 0th-order light can be expanded. And each amount of ± primary light can be explained.

At this time, the 0th-order light component of the phase distribution Φ (x, y) is J ₀ (2πr / a), the 1st-order light component is J ₁ (2πr / a), and the -1st-order light component is J _-1 (2πr / a). It is expressed as a). By the way, with respect to the ± 1st-order Bessel function, since there is a relationship of J ₁ (x) = −J _-1 (x), the magnitudes of the ± 1st-order optical components are equal. Here, the traveling wave AU in the positive direction of the Y-axis was considered as an example of the four traveling waves, but the same relationship is established for the other three waves (traveling waves AD, AR, AL), and ± primary light. The sizes of the components are equal. From the above discussion, in the conventional method of rotating the different refractive index region n04-mb around the lattice point O, it is difficult in principle to give a difference in the amount of light of the ± primary light component.

On the other hand, according to the phase modulation layer n04-m in which the arrangement pattern of the different refractive index region n04-mb is determined by the on-axis shift method, the primary light and the -1st order are obtained for a single traveling wave. When there is a difference in each amount of light, for example, when the inclination angle θ is 45 °, 135 °, 225 ° or 315 °, the closer the shift amount R ₀ is to the upper limit of the above-mentioned equation (9), the more ideal. Phase distribution can be obtained. As a result, the 0th-order light is reduced, and in each of the traveling waves AU, AD, AR, and AL, one of the primary light and the -1st-order light is selectively reduced. Therefore, in principle, it is possible to give a difference in the amount of light of the primary light and the -1st order light by selectively reducing one of the traveling waves traveling in opposite directions.

この位相分布Φ（ｘ，ｙ）の０次光および±１次光への寄与は、ｅｘｐ｛ｎΦ（ｘ，ｙ）｝（ｎ：整数）で展開した場合の、ｎ＝０およびｎ＝±１の成分で与えられる。ところで、下記の式（１３）によって表される関数ｆ（ｚ）をＬａｕｒｅｎｔ級数展開すると、以下の式（１４）で規定される数学公式が成り立つ。

ここで、ｓｉｎｃ（ｘ）＝ｘ／ｓｉｎ（ｘ）である。上記式（１４）で規定される数学公式を用いると、位相分布Φ（ｘ，ｙ）を級数展開することができ、０次光および±１次光の各光量を説明することができる。このとき、上記式（１４）の指数項ｅｘｐ｛ｊπ（ｃ－ｎ）｝の絶対値が１である点に注意すると、位相分布Φ（ｘ，ｙ）の０次光成分の大きさは、以下の式（１５）で表される。

また、位相分布Φ（ｘ，ｙ）の１次光成分の大きさは、以下の式（１６）で表される。

位相分布Φ（ｘ，ｙ）の－１次光成分の大きさは、以下の式（１７）で表される。

そして、上記式（１５）～（１７）においては、以下の式（１８）で規定される条件を満たす場合を除いて、１次光成分以外に０次光および－１次光成分が現れる。しかしながら、±１次光成分の大きさは互いに等しくならない。

FIG. 36 shows, as a method of determining the arrangement pattern of the different refraction rate region n04-mb, an on-axis shift method of moving the different refraction rate region on an axis inclined with respect to a square lattice through a grid point, and a traveling wave AU. It is a figure which shows AD, AR, AL. FIG. 36 (a) shows that the center of gravity G1 of the different refractive index region n04-mb moves on a straight line L that passes through the grid point O and is inclined with respect to both the s-axis and the t-axis that define the unit constituent region R. The reason why it is possible to selectively reduce either the primary light or the -1st order light in the above-mentioned axial shift method will be described. FIG. 36 (b) shows an example of four progressive waves with respect to the design phase φ (x, y) in the unit constituent region R (x, y) (corresponding to the rotation angle of FIG. 5 in the rotation method). Consider a traveling wave AU in the positive direction of the y-axis. At this time, due to the geometrical relationship, the deviation from the lattice point O is r · sin θ · {φ (x, y) −φ ₀ } / π for the traveling wave AU, so the phase difference is ( The relationship is 2π / a) r ・ sinθ ・ {φ (x, y) -φ ₀ } / π. Here, for the sake of simplicity, the inclination angle θ = 45 ° and the phase angle φ ₀ = 0 °. At this time, the phase distribution Φ (x, y) (corresponding to the above-mentioned phase distribution P (x, y)) with respect to the traveling wave AU has a small influence on the size of the different refractive index region n04-mb, so that influence is ignored. If possible, it is given by the following equation (12).

The contribution of this phase distribution Φ (x, y) to the 0th-order light and the ± 1st-order light is n = 0 and n = ± when expanded by exp {nΦ (x, y)} (n: integer). It is given by one component. By the way, when the function f (z) represented by the following equation (13) is expanded by the Laurent series, the mathematical formula defined by the following equation (14) is established.

Here, sinc (x) = x / sin (x). Using the mathematical formula defined by the above equation (14), the phase distribution Φ (x, y) can be expanded in a series, and the amount of each of the 0th-order light and the ± 1st-order light can be explained. At this time, paying attention to the fact that the absolute value of the exponential term exp {jπ (cn)} in the above equation (14) is 1, the magnitude of the 0th-order optical component of the phase distribution Φ (x, y) is. It is expressed by the following equation (15).

The magnitude of the primary light component of the phase distribution Φ (x, y) is expressed by the following equation (16).

The magnitude of the -1st order light component of the phase distribution Φ (x, y) is expressed by the following equation (17).

Then, in the above formulas (15) to (17), the 0th-order light and the -1st-order light component appear in addition to the primary light component, except when the condition defined by the following formula (18) is satisfied. However, the magnitudes of the ± primary light components are not equal to each other.

In the above explanation, the traveling wave AU in the positive direction of the Y axis is considered as an example of the four traveling waves, but the same relationship is established for the other three waves (traveling waves AD, AR, AL), and ± 1 There is a difference in the size of the secondary light component. From the above discussion, according to the on-axis shift method in which the different refractive index region n04-mb moves on the straight line L that passes through the grid point O and is inclined from the square grid, it is possible to give a difference in the amount of light of the ± primary light component. It is possible in principle. Therefore, in principle, it is possible to selectively extract only a desired optical image (first optical image portion B1 or second optical image portion B2) by reducing the -1st primary light or the primary light. Also in FIG. 32 (b) described above, it can be seen that there is a difference in intensity between the primary light and the -1st order light.

Further, in the on-axis shift method, the inclination angle θ (angle formed by the s axis and the straight line L) of the straight line L in the unit constituent region R may be constant in the phase modulation layer n04-m. This makes it possible to easily design the arrangement of the center of gravity G1 in the different refractive index region n04-mb. Further, in this case, the inclination angle may be 45 °, 135 °, 225 ° or 315 °. As a result, four fundamental waves traveling along the square grid (when the X-axis and Y-axis along the square grid are set, the light traveling in the positive direction of the X-axis, the light traveling in the negative direction of the X-axis, and the positive direction of the Y-axis). The traveling light and the light traveling in the negative direction of the Y-axis) can contribute evenly to the optical image. Further, when the inclination angle θ is 45 °, 135 °, 225 ° or 315 °, the direction of the electromagnetic field on the straight line L is aligned in one direction by selecting an appropriate band end mode, so that linear polarization is performed. Obtainable. As an example of such a mode, there are modes A and B shown in FIG. 3 of Non-Patent Document 3. When the inclination angle θ is 0 °, 90 °, 180 ° or 270 °, a pair of four traveling waves AU, AD, AR, and AL traveling in the Y-axis direction or the X-axis direction. Since the wave does not contribute to the primary light (signal light), it is difficult to improve the efficiency of the signal light.

The positional relationship between the active layer and the phase modulation layer n04-m can be easily photocoupled even if they are reversed along the Z-axis direction, as in the above-mentioned rotation method.

37 and 38 are diagrams showing various examples (on-axis shift method) of the planar shape of the different refractive index region. In the above example, the shape of the different refractive index region n04-mb on the XY plane is circular. However, the different refractive index region n04-mb may have a shape other than a circle. For example, the shape of the different refractive index region n04-mb may have mirror image symmetry (line symmetry). Here, the mirror image symmetry (line symmetry) is the planar shape of the different refractive index region n04-mb located on one side of a certain straight line along the XY plane and the straight line. It means that the planar shape of the different refractive index region n04-mb located on the other side of the above can be mirror image symmetric (line symmetry) with each other. Shapes having mirror image symmetry (line symmetry) include, for example, a perfect circle shown in FIG. 37 (a), a square shown in FIG. 37 (b), and a regular hexagon shown in FIG. 37 (c). The regular octagon shown in FIG. 37 (d), the regular hexagon shown in FIG. 37 (e), the rectangle shown in FIG. 37 (f), the ellipse shown in FIG. 37 (g), and the like are shown. Can be mentioned. As described above, when the shape of the different refractive index region n04-mb on the XY plane has mirror image symmetry (line symmetry), each of the unit constituent regions R of the virtual square lattice of the phase modulation layer n04-m. Since the shape is simple, the direction and position of the center of gravity G1 of the corresponding different refractive index region n04-mb can be determined with high accuracy from the lattice point O. That is, patterning with high accuracy is possible.

Further, the shape of the different refractive index region n04-mb on the XY plane may be a shape having no rotational symmetry of 180 °. Such shapes include, for example, a regular triangle shown in FIG. 38 (a), a right-angled isosceles triangle shown in FIG. 38 (b), and a portion of two circles or ellipses shown in FIG. 38 (c). Overlapping shape, oval shape shown in FIG. 38 (d), teardrop shape shown in FIG. 38 (e), isosceles triangle shown in FIG. 38 (f), shown in FIG. 38 (g). The arrow-shaped shape shown, the trapezoidal shape shown in FIG. 38 (h), the pentagonal shape shown in FIG. 38 (i), the shape in which parts of the two rectangles shown in FIG. 38 (j) overlap each other, and the figure. Examples thereof include a shape in which a part of the two rectangles shown in 38 (k) overlap each other and do not have mirror image symmetry. The egg-shaped shape is deformed so that the dimension in the minor axis direction near one end along the major axis of the ellipse is smaller than the dimension in the minor axis direction near the other end. The teardrop shape is a deformed shape of one end along the long axis of an ellipse into a pointed end that protrudes along the long axis. The arrow-shaped shape is a shape in which one side of a rectangle is recessed in a triangular shape and the opposite side is pointed in a triangular shape. As described above, since the shape of the different refractive index region n04-mb on the XY plane does not have the rotational symmetry of 180 °, higher light output can be obtained. The different refractive index region n04-mb may be composed of a plurality of elements as shown in FIGS. 38 (j) and 38 (k). In this case, the center of gravity of the different refractive index region n04-m may be formed. G1 is a synthetic center of gravity of a plurality of components.

FIG. 39 is a diagram showing still another example (on-axis shift method) of the planar shape of the different refractive index region. Further, FIG. 40 is a diagram showing a second modification of the phase modulation layer of FIG. 28.

In the examples shown in FIGS. 39 and 40, each different refractive index region n04-mb is composed of a plurality of components 15b and 15c. The center of gravity G1 is the combined center of gravity of all the components and is located on the straight line L. Both the components 15b and 15c have a second refractive index different from the first refractive index of the basic region n04-ma. Both the components 15b and 15c may be pores, or may be configured by embedding a compound semiconductor in the pores. In each of the unit constituent regions R, the constituent elements 15c are provided in a one-to-one correspondence with the constituent elements 15b. The center of gravity G1 in which the constituent elements 15b and 15c are combined is located on the straight line L that crosses the grid point O of the unit constituent region R that constitutes the virtual square grid. Both the constituent elements 15b and 15c are included in the range of the unit constituent region R constituting the virtual square grid. The unit constituent area R is an area surrounded by a straight line that divides the grid points of a virtual square grid into two equal parts.

The planar shape of the component 15c is, for example, circular, but can have different shapes, as in the various examples shown in FIGS. 37 and 38. 39 (a) to 39 (k) show examples of the shapes and relative relationships of the components 15b and 15c on the XY plane. 39 (a) and 39 (b) show a form in which both the components 15b and 15c have the same shape. 39 (c) and 39 (d) show a form in which both the components 15b and 15c have the same shape, and a part of each of them overlaps with each other. FIG. 39 (e) shows a form in which both the components 15b and 15c have the same shape, and the distance between the centers of the components 15b and 15c is arbitrarily set for each lattice point. FIG. 39 (f) shows a form in which the components 15b and 15c have figures having different shapes from each other. FIG. 39 (g) shows a form in which the components 15b and 15c have different shapes and shapes, and the distance between the centers of the components 15b and 15c is arbitrarily set for each grid point.

Further, as shown in FIGS. 39 (h) to 39 (k), the component 15b constituting a part of the different refractive index range n04-mb is composed of two regions 15b1 and 15b2 separated from each other. May be done. Then, the distance between the center of gravity of the regions 15b1 and 15b2 (corresponding to the center of gravity of a single component 15b) and the center of gravity of the component 15c may be arbitrarily set for each grid point. Further, in this case, as shown in FIG. 39 (h), the regions 15b1, 15b2 and the component 15c may have shapes having the same shape as each other. Alternatively, as shown in FIG. 39 (i), two of the regions 15b1, 15b2 and the component 15c may be different from the others. Further, as shown in FIG. 39 (j), even if the angle of the component 15c with respect to the s axis is arbitrarily set for each grid point in addition to the angle of the straight line connecting the regions 15b1 and 15b2 with respect to the s axis. good. Further, as shown in FIG. 39 (k), the angle of the straight line connecting the regions 15b1 and 15b2 with respect to the s axis is arbitrary for each grid point while the regions 15b1 and 15b2 and the component 15c maintain the same relative angle to each other. May be set to.

The planar shape of the different refractive index region n04-mb may be the same between the unit constituent regions R. That is, even if the different refractive index regions n04-mb have the same figure in all the unit constituent regions R and can be superimposed on each other between the grid points by a translation operation, or a translation operation and a rotation operation. good. In that case, it is possible to suppress the generation of noise light and 0th-order light that becomes noise in the beam projection pattern. Alternatively, the planar shapes of the different refractive index regions n04-mb do not necessarily have to be the same between the unit constituent regions R, and as shown in FIG. 40, for example, the shapes are different between the adjacent unit constituent regions R. You may. As shown in the examples of FIGS. 36 (a) and 36 (b), in any of FIGS. 37 to 40, the center of the straight line L passing through each grid point O is aligned with the grid point O. It is preferably set to.

As described above, even in the configuration of the phase modulation layer in which the arrangement pattern of the different refractive index region is determined by the on-axis shift method, the phase modulation layer in which the arrangement pattern of the different refractive index region is determined by the rotation method is applied. It is possible to preferably exert the same effect as that of the above-described embodiment.

100,200,300,100B ... Semiconductor light emitting element, 102,202,302,102B ... First clad layer, 103,203,303,103B ... Active layer, 104,204,304,104B ... Phase modulation layer, 104- m (m is a positive integer), 204-m, 304-m, 104B-m ... Phase modulation region, 104-ma, 204-ma, 304-ma, 104B-ma ... Basic region, 104-mb, 204- mb, 304-mb, 104B-mb ... Multiple different refractive index regions, 106, 206, 306, 106B ... Second clad layer, 108-m, 208-m, 308-m, 108B-m ... Second surface side Electrodes, 110, 210, 310, 110B-m ... First surface side electrodes, 112, 212, 312, 112B ... Separation region.

Claims (14)

A semiconductor having a first surface and a second surface facing the first surface, one of the first surface and the second surface functioning as a light emitting surface for outputting light and the other functioning as a support surface. It is a light emitting element
An active layer located between the first surface and the second surface,
A phase modulation layer located between the first surface and the second surface and including a plurality of phase modulation regions, each of which is optically coupled to the active layer, and each of the plurality of phase modulation regions is , A phase modulation layer including a basic region having a first refractive index and a plurality of different refractive index regions each provided in the basic region and having a second refractive index different from the first refractive index.
A first clad layer located on the side where the first surface is arranged with respect to a laminated structure including at least the active layer and the phase modulation layer.
A second clad layer arranged on the side where the second surface is located with respect to the laminated structure, and
The first surface side electrode arranged on the side where the first surface is located with respect to the first clad layer,
A plurality of second surface side electrodes each corresponding to the plurality of phase modulation regions arranged on the side where the second surface is located with respect to the second clad layer, and the stacking direction of the laminated structure. When viewed along the above, a plurality of second surface side electrodes arranged in a plurality of regions overlapping the plurality of phase modulation regions, respectively.
A common substrate layer arranged between the first clad layer and the first surface side electrode, which has a continuous surface holding the plurality of phase modulation regions, and a common substrate layer.
Equipped with
In each of the plurality of phase modulation regions included in the phase modulation layer, the plurality of different refractive index regions are obtained when a drive current is supplied from the corresponding second surface side electrode among the plurality of second surface side electrodes. According to the arrangement pattern for matching the beam projection pattern, which is the projection pattern of the light output from the light emitting surface, and the beam projection region on which the beam projection pattern is formed with the target beam projection pattern and the target beam projection region, respectively. , Placed in place in the basic area,
The arrangement pattern is
An XY plane including an X-axis and a Y-axis that are orthogonal to each other and that coincide with one surface of the phase modulation layer including the Z-axis that coincides with the normal direction of the light emitting surface and the plurality of different refractive index regions. In the XYZ orthogonal coordinate system defined by the above, the unit constituent regions R of M1 (one or more integers) × N1 (one or more integers) each having a square shape are formed on the XY plane. When a virtual square grid is set up
The unit constituent area R (x, In y), the center of gravity G1 of the different refractive index region located in the unit constituent region R (x, y) is a distance from the lattice point O (x, y) which is the center of the unit constituent region R (x, y). It is defined so that the vector from the lattice point O (x, y) to the center of gravity G1 is oriented in a specific direction while being separated by r .
When the lattice constant of the virtual square lattice is a, the distance r satisfies 0 ≦ r ≦ 0.3a.
The coordinates (x, y, z) in the XYZ Cartesian coordinate system are the length d1 of the driving diameter, the tilt angle θ _tilt from the Z axis , and the X axis specified on the XY plane. Satisfy the relationship shown by the following equations (1) to (3) with respect to the rotation angle θ _rot and the spherical coordinates (d1, θ _tilt , θ _rot ) defined by .

When the target beam projection pattern is a set of bright spots directed in the directions defined by the angles θ tilt and θ rot, the angles θ _tilt and _{θ rot} are _the standardized wave numbers specified by the following equation (4). Therefore, the coordinate value k _x on the Kx axis corresponding to the X axis and the standardized wave number defined by the following equation (5) corresponding to the Y axis and on the Ky axis orthogonal to the Kx axis. Converted to the coordinate value ky _of

In the wave number space defined by the Kx axis and the Ky axis, a specific wave number range including the beam projection pattern is an image of M2 (an integer of 1 or more) × N2 (an integer of 1 or more), each of which is a square shape. Consists of region FR
In the wave number space, the image region FR (k _x, ) specified by the coordinate component k _x (integer of 1 or more and M2 or less) in the Kx axis direction and the coordinate component ky ₍ integer of 1 or more and N2 or less) in the Ky axis direction . ky) The complex amplitude F (x, y) obtained by performing a two-dimensional inverse Fourier transform on each of the unit constituent regions R (x, _y ) on the XY plane has j as an imaginary unit . Given by the following equation (6),

In the unit constituent region R (x, y), when the amplitude term is A (x, y) and the phase term is P (x, y), the complex amplitude F (x, y) is as follows. Specified by equation (7) and

When the unit constituent region R (x, y) is defined by an s-axis and a t-axis that are parallel to the X-axis and the Y-axis and are orthogonal to the grid point O (x, y), respectively.
The phase modulation layer is
The angle φ (x, y) formed by the line segment connecting the lattice point O (x, y) and the center of gravity G1 of the corresponding different refractive index region and the s axis is
φ (x, y) = C × P (x, y) + B
C: Proportional constant
B: Arbitrary constant
The corresponding different refractive index regions satisfying the above relationship are configured to be arranged in the unit constituent region R (x, y).
The arrangement pattern in each of the phase modulation regions is defined so that the beam projection regions are equal regardless of which of the second surface side electrodes the drive current is supplied.
Semiconductor light emitting device. A semiconductor having a first surface and a second surface facing the first surface, one of the first surface and the second surface functioning as a light emitting surface for outputting light and the other functioning as a support surface. It is a light emitting element
An active layer located between the first surface and the second surface,
A phase modulation layer located between the first surface and the second surface and including a plurality of phase modulation regions, each of which is optically coupled to the active layer, and each of the plurality of phase modulation regions is , A phase modulation layer including a basic region having a first refractive index and a plurality of different refractive index regions each provided in the basic region and having a second refractive index different from the first refractive index.
A first clad layer located on the side where the first surface is arranged with respect to a laminated structure including at least the active layer and the phase modulation layer.
A second clad layer arranged on the side where the second surface is located with respect to the laminated structure, and
The first surface side electrode arranged on the side where the first surface is located with respect to the first clad layer,
A plurality of second surface side electrodes each corresponding to the plurality of phase modulation regions arranged on the side where the second surface is located with respect to the second clad layer, and the stacking direction of the laminated structure. A plurality of second surface side electrodes arranged in a plurality of regions overlapping with the plurality of phase modulation regions when viewed along the
A common substrate layer arranged between the first clad layer and the first surface side electrode, which has a continuous surface holding the plurality of phase modulation regions, and a common substrate layer.
Equipped with
In each of the plurality of phase modulation regions included in the phase modulation layer, the plurality of different refractive index regions are obtained when a drive current is supplied from the corresponding second surface side electrode among the plurality of second surface side electrodes. According to the arrangement pattern for matching the beam projection pattern, which is the projection pattern of the light output from the light emitting surface, and the beam projection region on which the beam projection pattern is formed with the target beam projection pattern and the target beam projection region, respectively. , Placed in place in the basic area,
The arrangement pattern is
An XY plane including an X-axis and a Y-axis that are orthogonal to each other and that coincide with one surface of the phase modulation layer including the Z-axis that coincides with the normal direction of the light emitting surface and the plurality of different refractive index regions. In the XYZ Cartesian coordinate system defined by When a virtual square grid is set up
The unit constituent area R (x, In y), the center of gravity G1 of the different refractive index region located in the unit constituent region R (x, y) is a distance from the lattice point O (x, y) which is the center of the unit constituent region R (x, y). It is defined so that the vector from the lattice point O (x, y) to the center of gravity G1 is oriented in a specific direction while being separated by r.
The coordinates (x, y, z) in the XYZ Cartesian coordinate system are the radius length d1 and the inclination angle θ from the Z axis. _tilt And the rotation angle θ from the X axis specified on the XY plane. _rot And the spherical coordinates defined by (d1, θ) _tilt , θ _rot ) Satisfies the relationship shown by the following equations (8) to (10).

The target beam projection pattern is set at an angle θ. _tilt And θ _rot When making a set of bright spots in the direction defined by, the angle θ _tilt And θ _rot Is a normalized wavenumber defined by the following equation (11), and is a coordinate value k on the Kx axis corresponding to the X axis. _x The coordinate value k on the Ky axis, which is the normalized wavenumber defined by the following equation (12) and corresponds to the Y axis and is orthogonal to the Kx axis. _y Converted to

In the wavenumber space defined by the Kx axis and the Ky axis, the specific wavenumber range including the beam projection pattern is a square M2 (integer of 1 or more) × N2 (integer of 1 or more), respectively. Consists of region FR,
In the wavenumber space, the coordinate component k in the Kx-axis direction _x (Integer of 1 or more and M2 or less) and the coordinate component k in the Ky axis direction _y Image area FR (k) specified by (integer of 1 or more and N2 or less) _x, k _y ) The complex amplitude F (x, y) obtained by two-dimensional inverse Fourier transform to the unit constituent region R (x, y) on the XY plane is as follows, with j as an imaginary unit. Given in equation (13),

In the unit constituent region R (x, y), when the amplitude term is A (x, y) and the phase term is P (x, y), the complex amplitude F (x, y) is as follows. Specified by equation (14) and

When the unit constituent region R (x, y) is defined by an s-axis and a t-axis that are parallel to the X-axis and the Y-axis and are orthogonal to the grid point O (x, y), respectively.
The phase modulation layer is
The center of gravity G1 of the corresponding different refractive index region is located on a straight line inclined from the s axis passing through the lattice point O (x, y), and corresponds to the lattice point O (x, y). The line length r (x, y) up to the center of gravity G1 in the different refractive index region is
r (x, y) = C × (P (x, y) -P ₀ )
C: Proportional constant
P ₀ : Arbitrary constant
The corresponding different refractive index regions satisfying the above relationship are configured to be arranged in the unit constituent region R (x, y).
The arrangement pattern in each of the phase modulation regions is defined so that the beam projection regions are equal regardless of which of the second surface side electrodes the drive current is supplied.
Semiconductor light emitting device. Claim 1 or 2 in which the arrangement pattern in each of the phase modulation regions is defined so that the beam projection pattern becomes the same when the drive current is supplied from any of the plurality of second surface side electrodes. The semiconductor light emitting device according to the above. The active layer, the first clad layer, and the second clad layer, which electrically separate each of the plurality of phase modulation regions and overlap the plurality of phase modulation regions when viewed from a direction along the Z axis. The semiconductor light emitting device according to any one of claims 1 to 3, further comprising a separation region for electrically separating a plurality of corresponding regions in each of the clad layers. The separation region is characterized by optically separating the plurality of corresponding regions in each of the active layer, the phase modulation layer, the first clad layer, and the second clad layer together with the plurality of phase modulation regions. The semiconductor light emitting device according to claim 4 . The separated region extends from the second surface toward the common substrate layer until it reaches the common substrate layer in the region between the adjacent phase modulation regions among the plurality of phase modulation regions.
The fourth or fifth aspect of the present invention, wherein the distance between the tip of the separation region and the first surface side electrode is not more than half the thickness of the common substrate layer in the direction along the Z axis. Semiconductor light emitting element. The separated region is among a semiconductor layer modified by an electric field caused by high-intensity light irradiation, a semiconductor layer insulated by impurity diffusion or ion implantation, and air gaps formed by dry etching or wet etching. The semiconductor light emitting device according to any one of claims 4 to 6 , wherein the semiconductor light emitting device is any one of them. In at least one phase modulation region among the plurality of phase modulation regions,
All of the plurality of different refractive index regions have a shape defined on the XY plane, an area defined on the XY plane, and a distance r defined on the XY plane. The semiconductor light emitting element according to any one of claims 1 to 7 , wherein at least one of them matches. The shapes of the plurality of different refractive index regions on the XY plane are a perfect circle, a square, a regular hexagon, a regular octagon, a regular hexagon, a regular triangle, a right-angled isosceles triangle, a rectangle, an ellipse, or two circles. By deforming the ellipse so that the shape in which a part of the ellipse overlaps, the dimension in the minor axis direction near one end along the major axis is smaller than the dimension in the minor axis direction near the other end. The obtained oval shape, a teardrop shape obtained by transforming one end of an ellipse along its long axis into a pointed end protruding along the long axis, an isosceles triangle, and one side of a rectangle It is one of an elliptical shape, a trapezoidal shape, and a pentagonal shape in which the side facing one side constitutes a triangular protrusion while forming a notch of a triangle, and a shape in which a part of two rectangles overlaps. The semiconductor light emitting element according to any one of claims 1 to 8 , wherein the semiconductor light emitting element is characterized by the above. At least one phase modulation region among the plurality of phase modulation regions is
The inner region composed of the unit constituent region R of M1 × N1 and the inner region.
An extended square grid that is an outer region provided so as to surround the outer periphery of the inner region and is defined by setting the same grid structure as the virtual square grid on the outer circumference of the virtual square grid. An outer region containing a plurality of peripheral grid point different refractive index regions arranged so as to overlap each other with the grid points,
The semiconductor light emitting device according to any one of claims 1 to 9 , wherein the semiconductor light emitting device is characterized by having. At least one phase modulation region among the plurality of phase modulation regions is
A plurality of grid point different refractive index regions respectively arranged in the unit constituent region R of M1 × N1, and each center of gravity G2 coincides with the grid point O of the corresponding unit constituent region R. The semiconductor light emitting device according to any one of claims 1 to 10 , further comprising a plurality of lattice point different refractive index regions. The manufacturing method for manufacturing the semiconductor light emitting device according to any one of claims 1 to 11 .
The first step of forming the common substrate layer and
A second step of forming an element body having a third surface and a fourth surface facing the third surface and facing the common substrate layer on the common substrate layer, wherein the element body is the first. The basic region in the phase modulation layer includes at least the active layer, the phase modulation layer, the first clad layer, and the second clad layer arranged between the three surfaces and the fourth surface. A second plurality of portions to be the plurality of phase modulation regions, each of which is composed of a single layer in which the plurality of portions including the plurality of different refractive index regions are arranged so as to be separated from each other by a predetermined distance. Process and
In the third step of forming a separation region for electrically separating a plurality of portions to be at least the plurality of phase modulation regions in the element main body, the separation region is formed from the third surface to the fourth surface. The third step, which is formed until the common substrate layer is reached,
Manufacturing method with. A claim that the distance between the tip of the separation region and the first surface side electrode is half or less of the thickness of the common substrate layer along the direction from the third surface to the fourth surface. 12. The manufacturing method according to 12. The separated region includes a semiconductor layer modified by an electric field caused by high-intensity light irradiation, a semiconductor layer insulated by impurity diffusion or ion implantation, and air gaps formed by dry etching or wet etching. The manufacturing method according to claim 12 or 13 , wherein the manufacturing method is any of the above.

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