Laser Diode, Optical Integrated Device, and Method for Manufacturing the Same

Abstract

An optical integration device may include: a substrate; a first laser diode disposed on the substrate and oscillating in a transverse magnetic mode (TM mode); and a second laser diode disposed on the substrate and oscillating in a transverse electric mode (TE mode), wherein the first laser diode includes a disk-shaped first body and a through hole penetrating the first body.

Description

Technical Field

[0001] The present invention relates to a laser diode, an optical integrated device, and a method of manufacturing the same, and more particularly, to an optical integrated device including a laser diode using transformation optics and a method of manufacturing the same. Background Art

[0002] Transformation optics is a research field that attempts to arbitrarily control the flow of light by controlling the distribution of material constants (e.g., dielectric constant, transmittance, and refractive index) in space. This has become a new paradigm in nano-optics research, and in addition to basic research, various application possibilities have also been proposed. Summary of the Invention

[0003] Technical Problem

[0004] An object of the present invention is to provide a laser diode and an optical integrated device having improved performance.

[0005] Technical Solution

[0006] The optical integrated device according to the present invention includes: a substrate; a first laser diode oscillating in a transverse magnetic mode (TM mode) on the substrate; and a second laser diode oscillating in a transverse electric mode (TE mode) on the substrate, wherein the first laser diode may include: a first body having a disc shape; and a through hole penetrating the first body.

[0007] According to some embodiments, the second laser diode may include a second body having a disc shape, wherein a distance from an upper surface of the substrate to an upper surface of the first body may be the same as a distance from the upper surface of the substrate to an upper surface of the second body.

[0008] According to some embodiments, the first body may have a non-uniform curvature.

[0009] According to some embodiments, an area ratio of the through holes per unit area of the first body may be non-uniform.

[0010] According to some embodiments, a number of the through holes per unit area of the first body may be non-uniform.

[0011] According to some embodiments, a diameter of the through holes per unit area of the first body may be non-uniform.

[0012] According to some embodiments, at least a part of the first body may have a non-uniform refractive index.

[0013] According to some embodiments, the optical integrated device may further include an optical waveguide on the substrate, the optical waveguide being located between the first laser diode and the second laser diode.

[0014] According to some embodiments, the first body may have a non-uniform curvature, wherein the curvature of the portion of the first body adjacent to the optical waveguide may be smaller than the curvature of another portion of the first body spaced apart from the optical waveguide.

[0015] According to some embodiments, each of the first body and the second body may include: an upper cladding layer and a lower cladding layer; and a gain medium disposed between the upper cladding layer and the lower cladding layer.

[0016] According to some embodiments, the diameter of the through hole may be smaller than the length of the wavelength of the emitted light.

[0017] In a laser diode including a body in the shape of a disk according to the present invention, the body may have a non-uniform curvature, and the TM mode and the TE mode may selectively oscillate according to the refractive index distribution in the body.

[0018] According to some embodiments, at least a portion of the body may have a non-uniform dielectric constant and oscillate in the TM mode.

[0019] According to some embodiments, the body may include: an upper cladding layer and a lower cladding layer; and a gain medium disposed between the upper cladding layer and the lower cladding layer.

[0020] According to some embodiments, the laser diode may further include a through hole penetrating the body.

[0021] According to some embodiments, the area ratio of the through holes per unit area of the body may be non-uniform.

[0022] According to some embodiments, the diameter of the through hole may be smaller than the length of the wavelength of the incident light.

[0023] A method of manufacturing an optical integrated device according to the present invention may include: forming a first semiconductor layer, a second semiconductor layer, and a gain medium layer disposed between the first semiconductor layer and the second semiconductor layer on a substrate; forming a mask layer on the second semiconductor layer; patterning the mask layer to form a first mask pattern and a second mask pattern; patterning the second semiconductor layer, the gain medium layer, and the first semiconductor layer by using the first mask pattern to form a first laser diode oscillating in the TM mode; and patterning the second semiconductor layer, the gain medium layer, and the first semiconductor layer by using the second mask pattern to form a second laser diode oscillating in the TE mode, wherein the step of forming the first laser diode may include: forming a through hole penetrating the second semiconductor layer, the gain medium layer, and the first semiconductor layer to control the refractive index of the patterned second semiconductor layer, the gain medium layer, and the first semiconductor layer.

[0024] According to some embodiments, the step of forming the first laser diode may include: controlling the path of incident light entering the patterned second semiconductor layer, the gain medium layer, and the first semiconductor layer by controlling the dielectric constants of the patterned second semiconductor layer, the gain medium layer, and the first semiconductor layer.

[0025] According to some embodiments, the step of controlling the dielectric constant may include: controlling the dielectric constant by controlling the area ratio of the vias per unit area of the first mask pattern.

[0026] Advantageous Effects

[0027] According to the concept of the present invention, transformation optics can be used to implement a laser diode (e.g., a laser diode oscillating in the TM mode). Therefore, when forming a laser diode (e.g., when growing a wafer for a laser diode), no external force (e.g., tensile stress, etc.) needs to be applied, so that a reduction in gain and a shortening of the lifetime can be prevented. In addition, a laser diode in the TM mode and a laser diode in the TE mode can be implemented on a single chip, enabling the TM mode and the TE mode to oscillate simultaneously. When the optical integration device according to an embodiment of the present invention is applied to the field of optical communication, since two different polarization modes (TM mode and TE mode) can be used for a single wavelength, the data transmission rate can be increased. Description of the Drawings

[0028] Figure 1a is a diagram according to some embodiments of the present invention, showing a laser diode.

[0029] Figure 1b shows Figure 1a the curvature of the body.

[0030] Figure 1c is a diagram showing the area ratio of the vias per unit area of the body according to an embodiment.

[0031] Figure 1d is a diagram showing the area ratio of the vias per unit area of the body according to an embodiment.

[0032] Figures 2a to 2h is a view showing the shape of the body according to an embodiment of the present invention obtained by applying transformation optics.

[0033] Figure 3a schematically shows a laser diode including the above Figure 1a optical integration device.

[0034] Figure 3b is a plan view of the Figure 3a optical integration device as viewed from above.

[0035] Figure 4It is a diagram showing the coupling of an optical waveguide and a first laser diode.

[0036] Figures 5a to 5d It is a diagram showing the process of forming Figure 3a the optical integration device. Detailed Description of the Invention

[0037] To fully understand the structure and effects of the present invention, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and various modifications and changes can be added. However, the technical idea of the present invention is fully disclosed through the description of this embodiment, and those of ordinary skill in the art to which the present invention pertains are fully informed.

[0038] In this specification, when a component is referred to as being on another component, the component can be directly formed on the other component, or a third component can be disposed between them. Additionally, in the drawings, for the effective description of the technical content, the thickness of the components is exaggerated. The same reference numerals denote the same elements throughout the specification.

[0039] The embodiments described herein will be described with reference to cross-sectional views and / or plan views, which are ideal illustrative views of the present invention. In the drawings, for the effective description of the technical content, the thickness of the films and regions is exaggerated. Therefore, the regions shown in the drawings have a schematic nature, and the shapes of the regions shown in the drawings are intended to show the specific shapes of the device regions and are not intended to limit the scope of the invention. In various embodiments of this specification, terms such as first, second, third, etc. are used to describe various components, but these components should not be limited by these terms. These terms are only used to distinguish one component from another. The embodiments described and shown herein also include their complementary embodiments.

[0040] The terms used in this specification are for describing the embodiments and are not intended to limit the present invention. In this specification, the singular form also includes the plural form unless specifically stated in the phrase. As used in the specification, "comprising" and / or its variants do not exclude the presence or addition of one or more other elements.

[0041] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

[0042] Figure 1a The laser diode 10 in the diagram according to some embodiments of the present invention is shown. Figure 1b It is a diagram showing Figure 1a the curvature of the main body 12.

[0043] The laser diode 10 according to an embodiment of the present invention can be formed by applying transformation optics. Transformation optics means that the path of light can be controlled by adjusting the distribution of material constants (refractive index) in space. In other words, a resonator with a specific shape can behave like a resonator with an effective shape, each of which depends on the refractive index (e.g., permittivity and / or permeability).

[0044] The laser diode 10 can selectively oscillate in the transverse magnetic mode (TM mode) and the transverse electric mode (TE mode) according to the refractive index distribution in the body 12. As an example, in this specification, a TM mode laser diode that oscillates in the TM mode by fixing the permeability in the body 12 and controlling the permittivity will be described as an example.

[0045] The laser diode 10 includes a body 12. The body 12 can be set in a disk shape. For example, the body 12 can have a microdisk shape.

[0046] Referring to Figure 1a and Figure 1b , the body 12 can have a non-uniform curvature. In other words, the plane of the body 12 may not be a perfect circle with a constant curvature. Curvature refers to the degree of bending of a curve, and if the radius of the arc of the corresponding part is R, the curvature can be defined as 1 / R. Figure 1b The first curvature 1 / (R1) of part A of the body 12 may be different from the first curvature 1 / (R2) of another part B of the body 12. The first curvature 1 / (R1) of a part A of the body 12 may be smaller than the first curvature 1 / (R2) of another part B of the body 12.

[0047] Referring again to Figure 1a , the body 12 can include a lower cladding layer 14a, an upper cladding layer 14b, and a gain medium 16.

[0048] The lower cladding layer 14a can include a semiconductor material. For example, the lower cladding layer 14a can include an n-type semiconductor material or a p-type semiconductor material. The lower cladding layer 14a can include, for example, any one of InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto.

[0049] The upper cladding layer 14b can have dimensions and / or a shape corresponding to the dimensions and / or shape of the lower cladding layer 14a. The upper cladding layer 14b can include a semiconductor material. For example, the upper cladding layer 14b can include an n-type semiconductor material or a p-type semiconductor material. The upper cladding layer 14b can include, for example, any one of InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto. The upper cladding layer 14b can have a conductivity type different from that of the lower cladding layer 14a.

[0050] The gain medium 16 may be disposed between the lower cladding layer 14a and the upper cladding layer 14b. The gain medium 16 may have dimensions and / or a shape corresponding to each of the lower cladding layer 14a and the upper cladding layer 14b. The gain medium 16 may absorb energy to generate laser light. The gain medium 16 may include multiple quantum wells. The gain medium 16 may include, for example, any one of InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto.

[0051] Through holes 18 penetrating the body 12 may be provided. Each of the through holes 18 may be formed to pass through the upper cladding layer 14b, the gain medium 16, and the lower cladding layer 14a. The diameter of the through hole 18 may be smaller than the length of the wavelength of the emitted light. For example, the diameter of the through hole 18 may be smaller than about 1 / 10 of the length of the wavelength of the emitted light. Depending on the area ratio of the through holes 18 per unit area of the body 12, a difference in the local dielectric constant may occur. For example, since the portion including the through hole 18 is in contact with air and / or includes air, the dielectric constant may be controlled according to the ratio of the through holes 18. As an example, referring to Figure 2f , the portion where the through holes 18 are formed in a relatively large number per unit area may have a lower dielectric constant than the portion where the through holes 18 are formed in a relatively small number per unit area.

[0052] Figure 1c is a view showing the area ratio of the through holes 18 per unit area of the body 12 according to an embodiment. Referring to Figure 1c , the area ratio of the through holes 18 per unit area of the body 12 may be non-uniform. For example, Figure 1c shows through holes 18 having the same diameter formed. The number of through holes 18 in the unit area UA1 of the portion A of the body 12 formed in Figure 1c may be different from the number of through holes 18 in the unit area UA2 of the portion B of the body 12. The number of through holes 18 in the unit area UA1 of the portion A of the body 12 may be smaller than the number of through holes 18 in the unit area UA2 of one portion B of the body 12. As an example, the number of through holes 18 in the unit area UA1 of the portion A of the body 12 may be one, and the number of through holes 18 in the unit area UA2 of one portion B of the body 12 may be four. Therefore, the area ratio of the through holes 18 in the unit area UA1 of the portion A of the body 12 may be smaller than the area ratio of the through holes 18 in the unit area UA2 of the portion B of the body 12.

[0053] Figure 1d is a view showing the area ratio of the through holes 18 per unit area of the body 12 according to an embodiment. Referring to Figure 1d , the area ratio of the through holes 18 per unit area of the body 12 may be non-uniform. For example,Figure 1d It is shown that through holes 18 with different diameters are formed in the main body 12. The number of through holes 18 in the unit area UA3 of part A of the main body 12 formed in Figure 1d can be the same as the number of through holes 18 in the unit area UA4 of part B of the main body 12. However, the diameter of the through holes 18 in the unit area UA3 of part A of the main body 12 can be smaller than the diameter of the through holes 18 in the unit area UA4 of part B of the main body 12. Therefore, the area ratio of the through holes 18 in the unit area UA3 of part A of the main body 12 can be smaller than the area ratio of the through holes 18 in the unit area UA4 of part B of the main body 12.

[0054] Figures 2a to 2f is a view showing the shape of the main body according to an embodiment of the present invention obtained by applying transformation optics. To explain the application of transformation optics, a cavity will be described as an example below. A cavity is an empty space surrounded by a conductive wall, and when the cavity is excited by microwaves (e.g., electromagnetic waves or light), it can resonate at a specific frequency / wavelength (e.g., the frequency / wavelength can be defined by the shape or size of the conductor wall).

[0055] First, a cavity C' with a deformed shape can be obtained by performing a coordinate transformation of the circular cavity C in Figure 2a in a general coordinate system. At this time, it is assumed that the circular cavity C in Figure 2b is a linear isotropic dielectric without source charges or source currents. If a conformal mapping is used as the coordinate transformation, the deformed cavity C' can be, for example, a spiral Figure 2a shape, but this is only an example and is not limited thereto. The coordinate system of the deformed cavity C' can be expressed as follows, for example. z = β(w + αw

[0056] z = β(w + αw 2 ),

[0057] Referring to Figure 2a and Figure 2b , when the coordinate transformation is an isometric transformation, the reflection angle X of the light L in the cavities C and C' before and after the transformation can remain the same. Therefore, referring to Figure 2c , the total reflection condition can be maintained in the deformed cavity C'. For example, the whispering gallery mode can be maintained inside the deformed cavity C'. The whispering gallery mode refers to a resonance phenomenon in which light is trapped for a very long time along the interface in a symmetric resonator (e.g., a sphere) due to total internal reflection or the corresponding resonant wave (mode) of light.

[0058] Referring to Figure 2d , the refractive index of the deformed cavity C' can be obtained as follows (in this case, it is assumed that the refractive index outside the cavity is 1). At this time, the deformed cavity C' can correspond to the one to be described laterFigure 2g of (a).

[0059] n0 = 1.8

[0060] Refer to Figure 2e , the deformed cavity C' can be transformed to have a constant refractive index. As an example, the deformed cavity C' can have a constant refractive index (e.g., n4) through a composite transformation (e.g., multiple mapping). This is to control the refractive index in the cavity, and the type and number of the composite transformation are not limited to this.

[0061] As an example, before performing the spiral coordinate transformation, the Möbius transformation can be performed as follows.

[0062] z1(ω)

[0063]

[0064] After performing the Möbius transformation and the coordinate transformation that only moves the center of the circular figure without changing its shape (refer to Figure 2f ), the final composite transformation can be performed (refer to Figure 2g of (b)).

[0065]

[0066] Thus, various spatial refractive index distributions of a deformed cavity shape can be obtained. In addition, if an appropriate composite function (e.g., Möbius transformation, etc.) is introduced in the intermediate process, the gap between the maximum refractive index and the minimum refractive index required for designing the transformed cavity can be reduced. Since most semiconductor materials have a limited refractive index value, reducing the refractive index difference required in the design can facilitate the realization of the transformed cavity. At this time, it is not necessary to know the specific functional formula for performing the conformal transformation of the external shape connecting the circular cavity and the deformed cavity (e.g., z of).

[0067] Refer to Figure 2h , by forming the through hole 18 in the deformed cavity C' to have a constant refractive index (e.g., n4), the refractive index of the deformed cavity C' can be controlled. Comparing Figure 2e and Figure 2h , when the through hole 18 is formed in the deformed cavity C', a difference in refractive index distribution can be ensured within the main body 12. For example, the refractive index of the part with many through holes 18 per unit area can have n3 which is smaller than n4. In addition, due to the multiple mapping, the refractive index difference ( Figure 2f n3 - n4 in) in the deformed cavity C' can be smaller than the refractive index difference in the deformed cavity C' of Figure 2d ( Figure 2dis smaller than n1 - n2). The theoretical background for selectively applying transformation optics to the TM mode is as follows.

[0068] Assume Figure 2a that the circular cavity C in is a linear isotropic dielectric without source charges or source currents. When applying transformation optics, the Maxwell equations in the frequency domain are transformed through a general coordinate transformation as shown in the following [Equation 1].

[0069] [Equation 1]

[0070]

[0071]

[0072] where and J are the Jacobian matrix related to the coordinate transformation.

[0073] Here, if a conformal mapping is adopted as the coordinate transformation, the tensors and can be as shown in the following [Equation 2].

[0074] [Equation 2]

[0075]

[0076] Regarding [Equation 2], in the case of the TM polarization mode , for the electric field a wave equation as shown in the following [Equation 3] is obtained.

[0077] [Equation 3]

[0078]

[0079] On the other hand, for [Equation 2], in the case of the TE polarization mode , for the magnetic field a wave equation as shown in the following [Equation 4] is obtained.

[0080] [Equation 4]

[0081]

[0082] Here, in order to realize a dielectric resonator based on actual transformation optics, the permeability is fixed to the value μ0 in vacuum, and only the permittivity ε can be adjusted to have different values according to the position. In this case, the tensors and are given as shown in the following [Equation 5].

[0083] [Equation 5]

[0084]

[0085] According to what is given above and the wave equations for TM / TE polarization modes are obtained as follows.

[0086] In the case of the TM polarization mode, the wave equation is as shown in the following [Equation 6].

[0087] [Equation 6]

[0088]

[0089] [Equation 6] is the same as [Equation 3] obtained from the complete transformation optics of both the transformed permeability and permittivity. That is, in the case of the TM polarization mode, even when only the permittivity is changed according to the transformation optics rules, this means that the TM mode in the original space (circular resonator: uniform cavity) is transformed into the target space (transformed resonator: non-uniform cavity) without loss of the quality factor Q.

[0090] However, in the case of the TE polarization mode, the wave equation is as shown in the following [Equation 7].

[0091] [Equation 7]

[0092]

[0093] Due to the new intermediate term, [Equation 7] (i.e., the wave equation for TE polarization) is different from [Equation 4] of the wave equation obtained from the complete transformation optics. This result means that the TE mode formed in a non-uniform dielectric cavity (transformed resonator) with a fixed permeability and a spatially varying permittivity is different from the TE mode obtained by simultaneously changing the permittivity and permeability in space (applying the complete transformation optics). The new intermediate term added in the form of Helmholtz acts like noise throughout the region of the transformed resonator, inevitably leading to a significant reduction in the quality value Q.

[0094] Conventional laser diodes usually oscillate in the TE mode because the reflectivity of the TE mode between the quantum well plates is higher than that of the TM mode, and the energy gain of the gain medium is also higher in the TE mode. However, in the case of a transformation cavity where the permeability is fixed and only the permittivity changes according to space, as described above, optical loss may occur in the TE mode, thus rapidly reducing the optical gain of the TE mode. Therefore, the TE polarization mode loses the mode competition for laser oscillation with the TM polarization mode, enabling the TM polarization mode to oscillate the laser diode 10. Since Maxwell's equations are equations in which the electric field and the magnetic field are perfectly symmetric, contrary to the equations by applying the principle of the present invention as described above, when the permittivity of the material constituting the resonator is fixed and only the permeability changes with respect to space to fabricate the resonator, contrary to the above situation, transformation optics can be perfectly applied only to the TE mode. In other words, theoretically, the Q factor of only the TM mode can be selectively reduced.

[0095] Figure 3a is a diagram schematically showing an optical integration device 1 including the above Figure 1a laser diode 10. Figure 3b is a plan view of the optical integration device 1 as viewed from above Figure 3a of the same.

[0096] Referring to Figure 3a and Figure 3b , the optical integration device 1 may include a first laser diode 10, a second laser diode 20, and an optical waveguide 30 on a substrate 100.

[0097] The first laser diode 10 may be disposed on one side of the substrate 100. The first laser diode 10 may be a laser diode that oscillates in the TM mode. The first laser diode 10 may include a first body 12. The first laser diode 10 may be the same as or similar to the laser diode 10 described with reference to Figures 1a to 2e , and the first body 12 may also be the same as or similar to the body 12. Therefore, for simplicity of description, redundant descriptions are omitted.

[0098] The second laser diode 20 may be disposed on the other side of the substrate 100. The second laser diode 20 may be a laser diode that oscillates in the TE mode. The second laser diode 20 may include a second body 22 having a disk shape. Different from the first body 12, the second body 22 may have a perfect circular shape. For example, the second body 22 may have the same curvature as the first body 12. Different from the first laser diode 10, the second laser diode 20 may be formed without applying transformation optics.

[0099] The second body 22 may include a lower cladding layer 24a, an upper cladding layer 24b, and a gain medium 26.

[0100] The lower cladding layer 24a may include a semiconductor material. For example, the lower cladding layer 24a may include an n-type or p-type semiconductor material. The lower cladding layer 24a may include any one of, for example, InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto.

[0101] The upper cladding layer 24b may have dimensions and / or a shape corresponding to those of the lower cladding layer 24a. The upper cladding layer 24b may include a semiconductor material. For example, the upper cladding layer 24b may include an n-type or p-type semiconductor material. The upper cladding layer 24b may include any one of, for example, InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto. The upper cladding layer 24b may have a conductivity type different from that of the lower cladding layer 24a.

[0102] The gain medium 26 may be disposed between the lower cladding layer 24a and the upper cladding layer 24b. The gain medium 16 may have dimensions and / or a shape corresponding to each of the lower cladding layer 24a and the upper cladding layer 24b. The gain medium 26 may absorb energy to generate a laser. The gain medium 26 may include multiple quantum wells. The gain medium 26 may include any one of, for example, InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto.

[0103] The optical waveguide 30 may be disposed on the substrate 100 between the first laser diode 10 and the second laser diode 20. The optical waveguide 30 may be disposed to have the same distance from each of the first laser diode 10 and the second laser diode 20.

[0104] The first support portion 112 that supports the first laser diode 10 and the second support portion 114 that supports the second laser diode 20 may be disposed on the substrate 100. Due to the first support portion 112 and the second support portion 114, the amount of light captured by each of the first laser diode 10 and the second laser diode 20 may be increased.

[0105] Referring to Figure 3b , a portion P1 of the first laser diode 10 may be closer to the optical waveguide 30 than another portion P2. For example, a portion P1 of the first body 12 may be adjacent to the optical waveguide 30, and another portion P2 of the first body 12 may be another portion spaced apart from the optical waveguide 30. The curvature of a portion P1 of the first body 12 may be smaller than the curvature of another portion P2 of the first body 12. Accordingly, the portion P1 adjacent to the optical waveguide 30 may be close to the line.

[0106] Figure 4 is a view showing the coupling of the optical waveguide 30 and the first laser diode 10. Referring to Figure 4, the portion P1 adjacent to the optical waveguide 30 is closer to the line, so that the coupling area can be increased compared with a conventional circular laser diode (e.g., the second laser diode). Therefore, the optical transmission efficiency can be improved.

[0107] According to the concept of the present invention, a laser diode (e.g., a laser diode oscillating in the TM mode) can be realized by transformation optics. Therefore, when forming the laser diode, no external force (e.g., tensile stress, etc.) needs to be applied, so that a reduction in gain and a shortening of the lifetime can be prevented. In addition, a laser diode in the TM mode and a laser diode in the TE mode can be realized on a single chip, so that the TM mode and the TE mode can oscillate simultaneously. When the optical integration device according to an embodiment of the present invention is applied to the field of optical communication, since two different polarization modes (TM mode and TE mode) can be used for a single wavelength, the data transmission rate can be increased.

[0108] Figures 5a to 5d is a diagram showing the process of forming Figure 3a the optical integration device 1. Hereinafter, the process of forming the optical integration device 1 will be described with reference to Figures 5a to 5d and Figure 3a the process of forming the optical integration device 1 will be described.

[0109] Referring to Figure 5a , a sacrificial layer 110, a first semiconductor layer 124a, a gain medium layer 126, and a second semiconductor layer 124b can be sequentially formed on a substrate 100. The substrate 100 can be a semiconductor substrate. For example, the substrate 100 can include any one of InP, InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto. The sacrificial layer 110 can include any one of InP, InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but this is only an example and is not limited thereto.

[0110] The first semiconductor layer 124a can include a semiconductor material. For example, the first semiconductor layer 124a can include an n-type or p-type semiconductor material. The first semiconductor layer 124a can include, for example, any one of InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto.

[0111] The second semiconductor layer 124b can have dimensions and / or shapes corresponding to those of the first semiconductor layer 124a. The second semiconductor layer 124b can include a semiconductor material. For example, the second semiconductor layer 124b can include an n-type or p-type semiconductor material. The second semiconductor layer 124b can include, for example, any one of InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto. The second semiconductor layer 124b can have a conductivity type different from that of the first semiconductor layer 124a.

[0112] The gain medium layer 126 may be disposed between the first semiconductor layer 124a and the second semiconductor layer 124b. The gain medium layer 126 may have dimensions and / or shapes corresponding to each of the first semiconductor layer 124a and the second semiconductor layer 124b. The gain medium layer 126 may absorb energy to generate laser light. The gain medium layer 126 may include multiple quantum wells. The gain medium layer 126 may include, for example, any one of InGaAsP, InGaAs, AlGaAsP, and AlGaAs, but is not limited thereto.

[0113] A resist layer 130 may be formed on the second semiconductor layer 124b. The resist layer 130 may include PMMA, but is not limited thereto.

[0114] Referring to Figure 5b , the resist layer 130 may be patterned to form a first mask pattern 132 and a second mask pattern 134. The first mask pattern 132 may have the same shape as the first body 12 described above, and the second mask pattern 134 may have the same shape as the second body 22 described above. The step of patterning the resist layer 130 may use an electron beam lithography process. The first mask pattern 132 may include an opening 133.

[0115] Referring to Figure 5c , the first body 12 may be formed by etching the second semiconductor layer 124b, the gain medium layer 126, and the first semiconductor layer 124a using the first mask pattern 132 as a mask. The second body 22 may be formed by etching the second semiconductor layer 124b, the gain medium layer 126, and the first semiconductor layer 124a using the second mask pattern 134 as a mask. The step of forming the first body 12 using the first mask pattern 132 and the step of forming the second body 22 using the second mask pattern 134 may be performed simultaneously. For example, the step of forming the first body 12 using the first mask pattern 132 and the step of forming the second body 22 using the second mask pattern 134 may be performed using dry etching. After forming the first body 12 and the second body 22, the first mask pattern 132 and the second mask pattern 134 may be removed.

[0116] Referring to Figure 5d, the first support portion 112 can be formed under the first main body 12 by etching the sacrificial layer 110. Similarly, the sacrificial layer 110 can be etched to form the second support portion 114 under each second main body 22. Due to the first support portion 112 and the second support portion 114, the first main body 12 and the second main body 22 can be spaced apart from the substrate 100, respectively. For example, the upper surface of the first main body 12 can be spaced apart from the upper surface of the substrate 100 by a first distance H1, and the upper surface of the second main body 22 can be spaced apart from the upper surface of the substrate 100 by a second distance H2. In this case, the first distance H1 and the second distance H2 can be equal to each other. Due to the first support portion 112 and the second support portion 114, the amount of light captured in the first laser diode 10 and the second laser diode 20 can be increased, respectively.

[0117] Then, referring again to Figure 3a , the optical integration device 1 can be fabricated by forming an optical waveguide 30 between the first laser diode 10 and the second laser diode 20.

[0118] The above description of the embodiments of the present invention provides examples for describing the present invention. Therefore, the technical idea of the present invention is not limited to the above embodiments, and it is obvious that those of ordinary skill in the art can make various modifications and changes by combining the above embodiments within the technical idea of the present invention.

Claims

1. An optical integrated device, the optical integrated device comprising: A substrate; A first laser diode that oscillates in a TM mode (transverse magnetic mode) on the substrate; And A second laser diode that oscillates in a TE mode (transverse electric mode) on the substrate and includes a second body in the shape of a disk, Wherein, the first laser diode includes: A first body in the shape of a disk; and A through hole that penetrates the first body.

2. The optical integration device according to claim 1, wherein The distance from the upper surface of the substrate to the upper surface of the first body is the same as the distance from the upper surface of the substrate to the upper surface of the second body.

3. The optical integration device according to claim 1, wherein, The first body has a non-uniform curvature.

4. The optical integration device according to claim 1, wherein, The area ratio of the through holes per unit area of the first body is non-uniform.

5. The optical integration device according to claim 4, wherein The number of through holes per unit area of the first body is non-uniform.

6. The optical integration device according to claim 4, wherein The diameter of the through holes per unit area of the first body is non-uniform.

7. The optical integration device according to claim 1, wherein, At least a part of the first body has a non-uniform refractive index.

8. The optical integrated device according to claim 1, the optical integrated device further comprising an optical waveguide located on the substrate, the optical waveguide being located between the first laser diode and the second laser diode.

9. The optical integration device according to claim 8, wherein, The first body has a non-uniform curvature, Wherein, the curvature of the part of the first body adjacent to the optical waveguide is smaller than the curvature of the other part of the first body spaced apart from the optical waveguide.

10. The optical integration device according to claim 2, wherein, Each of the first body and the second body includes: An upper cladding layer and a lower cladding layer; and A gain medium disposed between the upper cladding layer and the lower cladding layer.

11. The optical integration device according to claim 1, wherein, The diameter of the through hole is smaller than the length of the wavelength of the emitted light.

12. A method of manufacturing an optical integrated device, the method comprising: Forming a first semiconductor layer, a second semiconductor layer, and a gain medium layer disposed between the first semiconductor layer and the second semiconductor layer on the substrate; Forming a mask layer on the second semiconductor layer; Patterning the mask layer to form a first mask pattern and a second mask pattern; Patterning the second semiconductor layer, the gain medium layer, and the first semiconductor layer by using the first mask pattern to form a first laser diode that oscillates in a TM mode, the first laser diode including a first body in the shape of a disk; And Patterning the second semiconductor layer, the gain medium layer, and the first semiconductor layer by using the second mask pattern to form a second laser diode that oscillates in a TE mode, the second laser diode including a second body in the shape of a disk, Wherein, the step of forming the first laser diode includes: forming a through hole that penetrates the second semiconductor layer, the gain medium layer, and the first semiconductor layer to control the refractive index of the patterned second semiconductor layer, gain medium layer, and first semiconductor layer.

13. The method according to claim 12, wherein, The step of forming the first laser diode includes: controlling the path of incident light incident on the patterned second semiconductor layer, gain medium layer, and first semiconductor layer by controlling the dielectric constant of the patterned second semiconductor layer, gain medium layer, and first semiconductor layer.

14. The method according to claim 13, wherein, The step of controlling the dielectric constant includes: controlling the dielectric constant by controlling the area ratio of the through holes per unit area of the first mask pattern.

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