Composite photonic crystal semiconductor laser

Abstract

The composite photonic crystal semiconductor laser comprises an N-type side electrode, an N-type substrate region, an N-type limiting region, a composite photonic crystal region, an N-type connecting region, a defect region, a P-type limiting region, a P-type contact region, an insulating region and a P-type side electrode which are arranged from bottom to top, the composite photonic crystal area is composed of a plurality of identical or partially identical single-period units, and a periodic composite photonic crystal area or a quasi-periodic composite photonic crystal area is formed. The invention has the following advantages: semiconductor materials with different refractive indexes and semiconductor materials with different lattice constants are introduced into the single-cycle unit of the composite photonic crystal region, and the spatial mode distribution and parasitic stress distribution of the laser are regulated and controlled, so that the mode stability of the laser is improved, the parasitic stress and warping degree of a wafer are reduced, and the yield of the wafer is improved. And the laser performance and service life are improved.

Description

Technical Field

[0001] The present disclosure relates to the field of semiconductor lasers, and in particular, to a composite photonic crystal semiconductor laser. Background Art

[0002] Semiconductor lasers have high electro-optical conversion efficiency, good coherence, and small size, so semiconductor lasers are often used in pumping, fiber coupling, and material processing of solid-state lasers and fiber lasers. Introducing a photonic crystal structure in the epitaxial direction of a semiconductor laser can regulate the spatial mode of the laser, improve the mode stability of the laser, and reduce the size of the vertical far-field divergence angle of the laser. However, current photonic crystal semiconductor lasers do not take into account the parasitic stress of the laser during epitaxial growth, resulting in large parasitic stress of the laser, crystal quality deviation, and large warping of the chip, which affects the life and performance uniformity of the laser. For example, in a photonic crystal semiconductor laser based on the GaAs / AlGaAs system, the photonic crystal region is AlGaAs with different Al components; the material type of the single-period unit in the photonic crystal region is single; the lattice constant of the semiconductor material in the photonic crystal region is relatively large relative to the lattice constant of the substrate, resulting in a large warping of the laser.

[0003] In summary, the epitaxial structure of traditional photonic crystal semiconductor lasers only considers the change in the refractive index of the semiconductor material, but ignores the lattice constant distribution of the semiconductor material, resulting in large parasitic stress and warpage of the laser, which greatly reduces the growth quality of the semiconductor material, is not conducive to the in-chip uniformity of the laser performance, and sharply increases the difficulty of subsequent laser chip packaging. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a composite photonic crystal semiconductor laser in view of the above shortcomings. By constructing a composite photonic crystal structure, while regulating the light field of the laser, semiconductor materials with different lattice constants are introduced into the composite photonic crystal region to compensate for the parasitic stress of the laser and reduce the warping of the wafer.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: A composite photonic crystal semiconductor laser, comprising: N-type side electrode, forming the electric injection channel of the laser; N-type substrate region, used to support the semiconductor chip; N-type restriction area, used to limit the expansion of the light field; A composite photonic crystal region for simultaneously controlling the spatial mode and parasitic stress of the laser; An N-type connection region, used to connect the composite photonic crystal region and the defect region; Defective regions, including an N-type defective region, an active region, and a P-type defective region arranged from bottom to top; P-type restriction area, used to limit the expansion of the light field; A P-type contact region, used to form an ohmic contact with a P-type side electrode; Insulation area, used to limit the current injection channel on the P side; A P-type side electrode, located on the insulating region and the P-type contact region, for forming a current injection channel on the P side; The composite photonic crystal region is composed of a plurality of identical or partially identical single-periodic units to form a periodic composite photonic crystal region or a quasi-periodic composite photonic crystal region.

[0006] Furthermore, each single-period unit of the composite photonic crystal region is composed of multiple semiconductor materials, and at least one single-period unit contains one or more semiconductor materials with different refractive indices to achieve regulation of the optical spatial mode, and contains one or more semiconductor materials with different lattice constants to compensate for the parasitic stress of the semiconductor laser and reduce the warpage of the wafer.

[0007] Furthermore, the composite photonic crystal region is located on the P side of the semiconductor laser, or on the N side of the semiconductor laser, or on both the P side and the N side of the semiconductor laser.

[0008] Furthermore, the N-type substrate region, the N-type restriction region, the composite photonic crystal region, the N-type connection region, the defect region, the P-type restriction region, and the P-type contact region are all made of semiconductor materials.

[0009] Furthermore, the N-type restriction region, the active region, and the P-type restriction region are composed of multiple layers of semiconductor materials with different lattice constants, so as to adjust the stress distribution of the laser.

[0010] Furthermore, the N-type restriction region, active region, and P-type restriction region are composed of multiple layers of semiconductor materials with different refractive indices, so as to regulate the spatial mode distribution of the laser.

[0011] Furthermore, the ridge region of the composite photonic crystal semiconductor laser is formed by dry etching or wet etching to the N-type restriction region or the N-type defect region.

[0012] Furthermore, the composite photonic crystal semiconductor laser is pumped by electrical pumping or optical pumping.

[0013] Furthermore, the composite photonic crystal region has four identical single-period units, which are periodically distributed. The single-period units in the composite photonic crystal region include 1# semiconductor material, 2# semiconductor material, and 3# semiconductor material. 1# semiconductor material, 2# semiconductor material, and 3# semiconductor material are all constant component materials with different refractive index distributions and lattice constant distributions to regulate the spatial mode distribution and parasitic stress distribution of the laser.

[0014] Further, the composite photonic crystal region has three non-completely identical single-periodic units, which are quasi-periodically distributed, and the single-periodic units include 1# semiconductor material, 2# semiconductor material, 3# semiconductor material, 4# semiconductor material, 5# semiconductor material, and 6# semiconductor material, and 1# semiconductor material, 2# semiconductor material, 3# semiconductor material, 4# semiconductor material, 5# semiconductor material, and 6# semiconductor material are all materials whose material components all change linearly, and have different refractive indices and lattice constant distributions, so as to regulate the spatial mode distribution and parasitic stress distribution of the laser; The P-type confinement region has five semiconductor materials with constant components, namely, semiconductor material #11, semiconductor material #12, semiconductor material #13, semiconductor material #14, and semiconductor material #15. The five semiconductor materials #11, semiconductor material #12, semiconductor material #13, semiconductor material #14, and semiconductor material #15 have different refractive index and lattice constant distributions to regulate the spatial mode distribution and parasitic stress distribution of the laser.

[0015] The present invention adopts the above technical solution, and has the following technical effects compared with the prior art: By introducing semiconductor materials with different refractive indices and semiconductor materials with different lattice constants into the single-period unit of the composite photonic crystal region, the spatial mode distribution and parasitic stress distribution of the laser are simultaneously regulated, the mode stability of the laser is improved, the parasitic stress and warpage of the wafer are reduced, and the performance and life of the laser are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0017] Figure 1 is a cross-sectional view of a composite photonic crystal semiconductor laser according to Embodiment 1 of the present invention; Figure 2 yes Figure 1The refractive index distribution diagram of the composite photonic crystal semiconductor laser shown in the figure, in which x represents the spatial position in the epitaxial direction, and the ordinate n represents the refractive index of the material; Figure 3 yes Figure 1 The lattice constant distribution diagram of the composite photonic crystal semiconductor laser shown in the figure, in which x represents the spatial position in the epitaxial direction, and the vertical position a0 represents the lattice constant of the material; Figure 4 is a refractive index distribution diagram of the composite photonic crystal semiconductor laser according to Example 2 of the present invention; Figure 5 yes Figure 4 Lattice constant distribution diagram of the composite photonic crystal semiconductor laser shown. DETAILED DESCRIPTION

[0018] Embodiment 1, as Figure 1 As shown, a composite photonic crystal semiconductor laser comprises an N-type side electrode 1, an N-type substrate region 2, an N-type restriction region 3, a composite photonic crystal region 4, an N-type connection region 5, a defect region 6, a P-type restriction region 7, a P-type contact region 8, an insulating region 9 and a P-type side electrode 10 arranged from bottom to top, wherein the N-type side electrode 1 forms an electric injection channel of the laser; the N-type substrate region 2 is used to support the semiconductor chip; the N-type restriction region 3 is used to limit the expansion of the light field; the composite photonic crystal region 4 can simultaneously regulate the spatial mode and parasitic stress of the laser, and the N-type connection region 5 is used to connect the composite photonic crystal region 4 and the defect region 6; the defect region 6 comprises an N-type defect region 61, an active region 62 and a P-type defect region 63 arranged from bottom to top; the active region 62 may contain active materials such as semiconductor body materials, semiconductor quantum wells, semiconductor quantum wires, semiconductor quantum dots, etc., to provide gain for the laser. The P-type restriction region 7 is used to limit the expansion of the light field; the P-type contact region 8 is used to form an ohmic contact with the P-type side electrode 10; the insulating region 9 is used to limit the current injection channel on the P side; the P-type side electrode 10 is located on the insulating region 9 and the contact region 8, and is used to form a current injection channel on the P side.

[0019] The composite photonic crystal region 4 is composed of a plurality of identical or partially identical single-periodic units to form a periodic composite photonic crystal region or a quasi-periodic composite photonic crystal region; each single-periodic unit of the composite photonic crystal region 4 is composed of a plurality of semiconductor materials, and at least one single-periodic unit contains one or more semiconductor materials with different refractive indices to achieve regulation of the optical spatial mode, and contains one or more semiconductor materials with different lattice constants to compensate for the parasitic stress of the semiconductor laser and reduce the warpage of the wafer.

[0020] The composite photonic crystal region 4 is located on the P side of the semiconductor laser, or on the N side of the semiconductor laser, or on both the P side and the N side of the semiconductor laser.

[0021] The N-type substrate region 2, N-type restriction region 3, composite photonic crystal region 4, N-type connection region 5, defect region 6, P-type restriction region 7, and P-type contact region 8 are all made of semiconductor materials, including semiconductor materials such as GaAs, InP, GaN, AlGaAs, AlInAs, GaInAs, GaInP, AlInP, GaPAs, AlGaN, InGaN, AlGaInAs, AlGaInP, AlGaAsP, InGaAsP, AlGaAsSb, and GaInPSb; and the material distribution forms may be single-layer, multi-layer, or gradient.

[0022] The N-type restriction region 3, the active region 6, and the P-type restriction region 7 can be composed of multiple layers of semiconductor materials with different lattice constants to adjust the stress distribution of the laser; the N-type restriction region 3, the active region 6, and the P-type restriction region 7 can also be composed of multiple layers of semiconductor materials with different refractive indices to adjust the spatial mode distribution of the laser. The ridge region of the composite photonic crystal semiconductor laser is formed by dry etching or wet etching to the N-type restriction region or the N-type defect region.

[0023] The composite photonic crystal semiconductor laser is manufactured by using semiconductor processing techniques such as thin film growth, epitaxial growth, exposure, and corrosion, and does not require any special process.

[0024] The composite photonic crystal semiconductor laser is pumped by electric pumping or optical pumping.

[0025] The composite photonic crystal semiconductor laser is used in the field of semiconductor lasers.

[0026] Preferably, the composite photonic crystal region 4 has four identical single-period units, which are periodically distributed. The single-period units of the composite photonic crystal region 4 include 1# semiconductor material 41, 2# semiconductor material 42, and 3# semiconductor material 43. 1# semiconductor material 41, 2# semiconductor material 42, and 3# semiconductor material 43 are all constant component materials with different refractive index distributions and lattice constant distributions to regulate the spatial mode distribution and parasitic stress distribution of the laser.

[0027] Figure 2 yes Figure 1 The possible refractive index distribution diagram of the composite photonic crystal semiconductor laser in the epitaxial direction of the embodiment shown, the horizontal axis x is the spatial position in the epitaxial direction, the unit is μm; the vertical axis n is the refractive index distribution in the epitaxial direction. The three semiconductor materials 1# semiconductor material 41, 2# semiconductor material 42, and 3# semiconductor material 43 of the single period unit of the composite photonic crystal region 4 have different refractive index distributions, which can adjust the spatial mode distribution of the laser.

[0028] Figure 3 yes Figure 1 The possible lattice constant distribution diagram of the composite photonic crystal semiconductor laser in the epitaxial direction of the illustrated embodiment, the horizontal axis x is the spatial position in the epitaxial direction, the unit is μm; the vertical axis a0 is the lattice constant distribution in the epitaxial direction, the unit is Å. The semiconductor materials 1# semiconductor material 41, 2# semiconductor material 42, and 3# semiconductor material 43 of the single period unit of the composite photonic crystal region 4 have different lattice constant distributions, which can regulate the parasitic stress distribution of the laser. Among them, the lattice constants of 1# semiconductor material 41 and 3# semiconductor material 43 are relatively large, and can be semiconductor materials with relatively large lattice constants such as AlGaAs; the lattice constant of 2# semiconductor material 42 is relatively small, and can be semiconductor materials with relatively small lattice constants such as AlGaAsP, so as to compensate for the stress in the growth process of the laser, improve the material quality, and reduce the warping of the chip.

[0029] Embodiment 2, Figure 4 It is a refractive index distribution diagram of the composite photonic crystal semiconductor laser of Example 2 of the present disclosure, wherein the abscissa x is the spatial position in the epitaxial direction, in μm; and the ordinate n is the refractive index distribution in the epitaxial direction.

[0030] The composite photonic crystal region 4 has three non-completely identical single-periodic units, which are quasi-periodically distributed. The single-periodic unit has 1# semiconductor material 41, 2# semiconductor material 42, 3# semiconductor material 43, 4# semiconductor material 44, 5# semiconductor material 45, and 6# semiconductor material 46. 1# semiconductor material 41, 2# semiconductor material 42, 3# semiconductor material 43, 4# semiconductor material 44, 5# semiconductor material 45, and 6# semiconductor material 46 are all materials whose material components change linearly, and have different refractive index and lattice constant distributions to regulate the spatial mode distribution and parasitic stress distribution of the laser. The P-type confinement region 7 has five semiconductor materials with constant components: 11# semiconductor material 71, 12# semiconductor material 72, 13# semiconductor material 73, 14# semiconductor material 74, and 15# semiconductor material 75. The five semiconductor materials #11 semiconductor material 71 , #12 semiconductor material 72 , #13 semiconductor material 73 , #14 semiconductor material 74 , and #15 semiconductor material 75 also have different refractive index and lattice constant distributions to adjust the spatial mode distribution and parasitic stress distribution of the laser.

[0031] like Figure 4In the embodiment shown, semiconductor material #1 41, semiconductor material #2 42, semiconductor material #3 43, semiconductor material #4 44, semiconductor material #5 45, and semiconductor material #6 46 have different refractive index distributions, which can adjust the spatial mode distribution of the laser. The five semiconductor materials #11 71, semiconductor material #12 72, semiconductor material #13 73, semiconductor material #14 74, and semiconductor material #15 75 also have different refractive index distributions, which can adjust the spatial mode distribution of the laser.

[0032] Figure 5 for Figure 4 The possible lattice constant distribution diagram of the composite photonic crystal semiconductor laser in the epitaxial direction of the illustrated embodiment, the horizontal axis x is the spatial position in the epitaxial direction, the unit is μm; the vertical axis a0 is the lattice constant distribution in the epitaxial direction, the unit is Å. The six semiconductor materials of the single period unit of the composite photonic crystal region 4, namely, the 1# semiconductor material 41, the 2# semiconductor material 42, the 3# semiconductor material 43, the 4# semiconductor material 44, the 5# semiconductor material 45, and the 6# semiconductor material 46, have different lattice constant distributions, which can regulate the parasitic stress distribution of the laser. Among them, the lattice constants of the 1# semiconductor material 41, the 3# semiconductor material 43, the 4# semiconductor material 44, and the 6# semiconductor material 46 are relatively large, and can be semiconductor materials with relatively large lattice constants such as AlGaAs; the lattice constants of the 2# semiconductor material 42 and the 5# semiconductor material 45 are relatively small, and can be semiconductor materials with relatively small lattice constants such as AlGaAsP, so as to compensate for the stress in the growth process of the laser, improve the material quality, and reduce the warpage of the chip. The five semiconductor materials 11# semiconductor material 71, 12# semiconductor material 72, 13# semiconductor material 73, 14# semiconductor material 74, and 15# semiconductor material 75 of the P-type restriction region 7 have different lattice constant distributions, which can adjust the parasitic stress distribution of the laser. Among them, the lattice constants of 11# semiconductor material 71, 13# semiconductor material 73, and 15# semiconductor material 75 are relatively large, and can be semiconductor materials with relatively large lattice constants such as AlGaAs; the lattice constants of 12# semiconductor material 72 and 14# semiconductor material 74 are relatively small, and can be semiconductor materials with relatively small lattice constants such as AlGaAsP, so as to compensate for the stress in the growth process of the laser, improve the material quality, and reduce the warpage of the chip.

[0033] According to the above-mentioned embodiments of the present disclosure, for the composite photonic crystal semiconductor laser and its application, the composite photonic crystal region is composed of multiple identical or partially identical single-periodic units to form a periodic composite photonic crystal region or a quasi-periodic composite photonic crystal region; each single-periodic unit of the composite photonic crystal region is composed of multiple semiconductor materials, and at least one single-periodic unit contains one or more semiconductor materials with different refractive indices to achieve the regulation of optical spatial modes, and contains one or more semiconductor materials with different lattice constants to compensate for the parasitic stress of the semiconductor laser and reduce the warpage of the wafer.

[0034] The description of the present invention is given for the purpose of illustration and description, and is not intended to be exhaustive or to limit the invention to the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for particular uses.

Claims

1. A composite photonic crystal semiconductor laser, characterized in that: Including bottom-up settings: An N-type side electrode (1) forms an electric injection channel for the laser; An N-type substrate region (2) for supporting a semiconductor chip; An N-type restriction region (3) for limiting the expansion of the light field; A composite photonic crystal region (4) for simultaneously controlling the spatial mode and parasitic stress of the laser; An N-type connection region (5) used to connect the composite photonic crystal region (4) and the defect region (6); The defect region (6) comprises an N-type defect region (61), an active region (62), and a P-type defect region (63) arranged from bottom to top; A P-type restriction region (7), used to restrict the expansion of the light field; A P-type contact region (8) used to form an ohmic contact with a P-type side electrode (10); An insulating region (9) for limiting the current injection channel on the P side; A P-type side electrode (10), located on the insulating region (9) and the P-type contact region (8), and used to form a current injection channel on the P side; The composite photonic crystal region (4) is composed of a plurality of identical or partially identical single-periodic units, forming a periodic composite photonic crystal region or a quasi-periodic composite photonic crystal region.

2. A composite photonic crystal semiconductor laser as claimed in claim 1, characterized in that: Each single-period unit of the composite photonic crystal region (4) is composed of a plurality of semiconductor materials, and at least one single-period unit contains one or more semiconductor materials with different refractive indices to achieve regulation of optical spatial modes, and contains one or more semiconductor materials with different lattice constants to compensate for parasitic stress of semiconductor lasers and reduce warpage of wafers.

3. A composite photonic crystal semiconductor laser as claimed in claim 1, characterized in that: The composite photonic crystal region (4) is located on the P side of the semiconductor laser, or on the N side of the semiconductor laser, or on both the P side and the N side of the semiconductor laser.

4. A composite photonic crystal semiconductor laser as claimed in claim 1, characterized in that: The N-type substrate region (2), the N-type restriction region (3), the composite photonic crystal region (4), the N-type connection region (5), the defect region (6), the P-type restriction region (7), and the P-type contact region (8) are all made of semiconductor materials.

5. A composite photonic crystal semiconductor laser as claimed in claim 1, characterized in that: The N-type limiting region (3), the active region (6), and the P-type limiting region (7) are composed of multiple layers of semiconductor materials with different lattice constants, so as to adjust the stress distribution of the laser.

6. A composite photonic crystal semiconductor laser as claimed in claim 1, characterized in that: The N-type limiting region (3), the active region (6), and the P-type limiting region (7) are composed of multiple layers of semiconductor materials with different refractive indices, and regulate the spatial mode distribution of the laser.

7. A composite photonic crystal semiconductor laser as claimed in claim 1, characterized in that: The ridge region of the composite photonic crystal semiconductor laser is formed by dry etching or wet etching to the N-type restriction region or the N-type defect region.

8. A composite photonic crystal semiconductor laser as claimed in claim 1, characterized in that: The composite photonic crystal semiconductor laser is pumped by electric pumping or optical pumping.

9. A composite photonic crystal semiconductor laser as claimed in claim 1, characterized in that: The composite photonic crystal region (4) has four identical single-period units that are periodically distributed. The single-period units of the composite photonic crystal region (4) include a 1# semiconductor material (41), a 2# semiconductor material (42), and a 3# semiconductor material (43). The 1# semiconductor material (41), the 2# semiconductor material (42), and the 3# semiconductor material (43) are all constant component materials with different refractive index distributions and lattice constant distributions, so as to regulate the spatial mode distribution and parasitic stress distribution of the laser.

10. The composite photonic crystal semiconductor laser according to claim 1, characterized in that: The composite photonic crystal region (4) has three non-completely identical single-periodic units, which are quasi-periodically distributed. The single-periodic units include 1# semiconductor material (41), 2# semiconductor material (42), 3# semiconductor material (43), 4# semiconductor material (44), 5# semiconductor material (45), and 6# semiconductor material (46). The 1# semiconductor material (41), 2# semiconductor material (42), 3# semiconductor material (43), 4# semiconductor material (44), 5# semiconductor material (45), and 6# semiconductor material (46) are all materials whose material components all change linearly, and have different refractive indices and lattice constant distributions, so as to regulate the spatial mode distribution and parasitic stress distribution of the laser. The P-type confinement region (7) comprises five semiconductor materials with constant components, namely, semiconductor material #11 (71), semiconductor material #12 (72), semiconductor material #13 (73), semiconductor material #14 (74), and semiconductor material #15 (75); the five semiconductor materials #11 (71), semiconductor material #12 (72), semiconductor material #13 (73), semiconductor material #14 (74), and semiconductor material #15 (75) have different refractive index and lattice constant distributions to regulate the spatial mode distribution and parasitic stress distribution of the laser.

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