Laser element and method for manufacturing the same

Abstract

Embodiments of the present invention provide a laser element and a method for manufacturing the same. The laser element includes a first cladding layer, an optical waveguide disposed on the first cladding layer, a second cladding layer disposed on the optical waveguide, a first electrode disposed on the second cladding layer, and a virtual cladding disposed on the optical waveguide and separated from the second cladding layer and the first electrode.

Description

Technical Field

[0001] Embodiments of the present invention relate to a laser element and a method of manufacturing the same. Background Art

[0002] An optical transceiver used in optical communication is optically coupled to an optical fiber. In order to economically produce an optical transceiver, it is necessary to couple a waveguide capable of transmitting a signal in an optical element and an optical fiber without loss at the minimum cost. This is because higher coupling efficiency leads to economic feasibility.

[0003] For mode matching between a laser diode and an optical fiber, a mode size converter (spot size converter; SSC) can be used. For mode matching between a laser diode and an optical fiber, the near field pattern (NFP) of the laser diode must be large, and the far filed pattern (FFP) must be small, where the far field pattern is a diffracted pattern of the NFP. A laser diode having an SSC can achieve mode matching between the laser diode and the optical fiber by reducing the FFP.

[0004] In addition, when an active region and a passive region are monolithically integrated into one element, the passive region has a different material composition to perform functions such as amplification and optical modulation. For coupling between these regions, a butt joint structure can be used.

[0005] Referring to Figure 1 (a) of, for a conventional laser element, after forming an active waveguide AL1, the active waveguide AL1 is partially etched using a mask 201, and passive waveguides SL1 and SL2 are regenerated. The passive waveguides SL1 and SL2 are regenerated in regions other than the masks 201, 202, and 203, and do not grow on the masks 201, 202, and 203. Thereafter, as Figure 1 shown in (b) of, an upper cladding layer 31 is etched to form an SSC structure 32, and an electrode 204 is formed on the SSC structure 32. Then, each chip unit region is cut to manufacture a plurality of laser diodes 21, 22, and 23.

[0006] However, when the SSC structures 32 of the chip unit regions face each other, the passive waveguides SL1 and SL2 have different thicknesses and compositions.

[0007] For example, the area of the first region D1 between the first mask 201 and the second mask 202 is small, so regeneration therein is relatively fast, while the area of the second region D2 between the second mask 202 and the third mask 203 is large, so regeneration therein is relatively slow. Therefore, the regeneration thicknesses of the first region D1 and the second region D2 are different from each other. In addition, due to the selective area growth (SAG) effect, the compositions of the first region D1 and the second region D2 are different from each other. Thus, a qualitative difference in the passivation material is generated, such that the amount of absorption of the reflected light based on the refractive index is different, resulting in quality defects of the device.

[0008] In addition, as Figure 2a shown, when forming the SSC structure for each chip unit region, the width of the upper cladding layer changes sharply with the cutting position of the chip, resulting in a reduced yield.

[0009] As Figure 2b shown, when cutting at position X1 due to the process margin, the upper cladding layer of the second laser diode 22 undergoes a sharp width change, rendering the second laser diode 22 unusable.

[0010] As Figure 2c shown, when cutting at position X2, the upper cladding layer of the first laser diode 21 undergoes a sharp width change, rendering the first laser diode 21 unusable. Summary of the Invention

[0011] [Technical Problem]

[0012] The present invention provides a laser device and a method for manufacturing the same, in which the uniformity of the regeneration thickness and composition of the passive optical waveguide can be improved.

[0013] There is also provided a laser device and a method for manufacturing the same, in which the yield can be maintained despite process errors at the cutting position of the chip.

[0014] The problems to be solved in the embodiments are not limited to this, and include the invention purpose or effect that can be understood from the solutions or embodiments of the following problems.

[0015] [Technical Solution]

[0016] According to one aspect of the present disclosure, there is provided a laser device, including a first cladding layer; an optical waveguide disposed on the first cladding layer; a second cladding layer disposed on the optical waveguide; a first electrode disposed on the second cladding layer; and a virtual cladding disposed on the optical waveguide and separated from the second cladding layer and the first electrode.

[0017] The virtual cladding may include a first virtual cladding and a second virtual cladding, and the area of the first virtual cladding may be larger than the area of the second virtual cladding.

[0018] The thickness of the second cladding layer, the thickness of the first virtual cladding, and the thickness of the second virtual cladding may be equal to each other.

[0019] The length of the first virtual cladding may be equal to the length of the second virtual cladding.

[0020] The first electrode may be disposed between the first virtual cladding and the second virtual cladding.

[0021] The compositions of the first virtual cladding and the second virtual cladding may be the same as the composition of the second cladding layer.

[0022] The first virtual cladding may be equal to the maximum width of the second cladding layer, and

[0023] The second virtual cladding may be equal to the minimum width of the second cladding layer.

[0024] The virtual cladding may include a first virtual cladding disposed at a first corner, a second virtual cladding disposed at a second corner, a third virtual cladding disposed at a fourth corner, and a fourth virtual cladding disposed at a third corner. The first virtual cladding and the third virtual cladding may have the same width, and the second virtual cladding and the fourth virtual cladding may have the same width.

[0025] The width of the first virtual cladding may be half of the maximum width of the optical waveguide, and the width of the second virtual cladding may be half of the minimum width of the optical waveguide.

[0026] The optical waveguide may include a first optical waveguide and a second optical waveguide surrounding the first optical waveguide.

[0027] The second cladding layer may be formed to have a width that narrows in one direction.

[0028] According to another aspect of the present disclosure, a method for manufacturing a laser element is provided. The method includes: forming a first optical waveguide on a first cladding layer; forming a second optical waveguide on the first cladding layer; forming a second cladding layer on the first optical waveguide and the second optical waveguide; dividing the second cladding layer into a plurality of second cladding layers by etching the second cladding layer; and performing cutting to form a plurality of chips. Wherein, the formation of the second optical waveguide includes dividing the first optical waveguide into a plurality of first optical waveguides by etching the first optical waveguide, and forming a second optical waveguide in the region where the first optical waveguide is etched. The plurality of first optical waveguides are alternately arranged in a first direction.

[0029] Dividing into a plurality of second cladding layers may include dividing the second cladding layer into a plurality of second cladding layers by etching the second cladding layer, and the plurality of second cladding layers are respectively disposed on the plurality of first optical waveguides.

[0030] A plurality of second coating layers may be alternately arranged in the longitudinal direction.

[0031] A plurality of second coating layers may be respectively arranged in a plurality of chip unit regions, and both ends of the second coating layer may extend to the outside of the chip unit region.

[0032] In the step of performing cutting to form a plurality of chips, the chips may be separated such that when both ends of the plurality of second coating layers are cut in a direction perpendicular to the longitudinal direction of the second coating layer, they are partially cut.

[0033] Forming a plurality of second coating layers may include forming a plurality of second coating layers such that the width of the end portion of the second coating layer becomes narrower.

[0034] [Beneficial effects]

[0035] According to the embodiment, the uniformity of the passive optical waveguide regeneration thickness and composition can be improved. Therefore, the light-emitting performance of the light-emitting surface AR and the light-reflecting performance of the light-reflecting surface HR can be enhanced.

[0036] In addition, even when an error occurs in the cutting position of chip separation, the yield can be maintained.

[0037] In addition, in the application of various chip structures such as a spot size converter (SSC) structure, the yield can be maintained.

[0038] In addition, the coupling loss can be reduced.

[0039] Various useful advantages and effects of the present disclosure are not limited to the foregoing description, and the above advantages and effects can be more easily understood during the process of describing the specific embodiments of the present disclosure.

[0040] Brief description of the drawings

[0041] Figure 1 A plan view and a sectional view showing a conventional laser element manufacturing process are shown.

[0042] Figure 2a Is a plan view showing another conventional laser element manufacturing process.

[0043] Figure 2b Is a view showing a chip cut at position X1 due to processing error.

[0044] Figure 2c Is a view showing a chip cut at position X2 due to processing error.

[0045] Figure 3 Is a conceptual diagram of a laser element according to an embodiment of the present disclosure.

[0046] Figure 4 is a perspective view of a laser element according to an embodiment of the present disclosure.

[0047] Figure 5 is a plan view of the figure.

[0048] Figure 6 is a conceptual diagram of a laser element according to another embodiment of the present disclosure.

[0049] Figures 7 to 15 is a view showing a method for manufacturing a laser element according to an embodiment of the present disclosure.

[0050] Figure 16 is a plan view showing a state in which a plurality of chip unit regions in a method for manufacturing a laser element according to an embodiment of the present disclosure are cut on a substrate.

[0051] Figure 17 is a plan view of a sheared chip.

[0052] Figure 18 is a plan view showing a state in which a plurality of chip unit regions are divided in a method for manufacturing a laser element according to another embodiment of the present disclosure.

[0053] Figure 19 is a plan view of a chip.

[0054] Figure 20 is a plan view showing a state in which a plurality of chip unit regions are divided on a substrate in a method for manufacturing a laser element according to yet another embodiment of the present disclosure.

[0055] Figure 21 is a plan view of a cut chip.

[0056] Figure 22 is a plan view showing a state in which a plurality of chip unit regions in a method for manufacturing a laser element according to yet another embodiment of the present disclosure are cut on a substrate.

[0057] Figure 23 is a plan view of a cut chip. Detailed Description

[0058] Existing embodiments can be modified into other forms or multiple embodiments can be combined, and the scope of the present disclosure is not limited to the embodiments described below.

[0059] Even when details described in a specific embodiment are not described in another embodiment, those described details can be understood as descriptions related to the other embodiment, unless there are descriptions contrary to or conflicting with the details in the other embodiment.

[0060] For example, when the features of component A are described in a specific embodiment and the features of component B are described in another embodiment, an embodiment in which component A and component B are combined with each other, although not explicitly described, should be understood to fall within the scope of the present disclosure, unless there is a contrary or contradictory description.

[0061] In the description of an embodiment, when any element is described as being formed "on or under" another element, "on or under" may include the two elements being in direct contact with each other, or one or more other elements being indirectly disposed between the two elements. The expression "on or under" may include the meaning of the downward direction and the upward direction with respect to one element.

[0062] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings to allow those of ordinary skill in the art to easily implement the embodiments of the present disclosure.

[0063] Figure 3 is a conceptual diagram of a laser element according to an embodiment of the present disclosure, Figure 4 is Figure 3 a plan view of, and Figure 5 is a conceptual diagram of a laser element according to another embodiment of the present disclosure.

[0064] Referring to Figure 3 , the laser element according to the embodiment may include a first cladding layer 121, optical waveguides 125 and 140, a second cladding layer 150, and a first electrode 170.

[0065] The laser element may include an active region 10 and a passive region 20. The optical waveguide may include a first optical waveguide (active optical waveguide) S1 disposed in the active region 10 and a second optical waveguide (passive optical wave) 140 disposed in the passive region. The first optical waveguide S1 and the second optical waveguide 140 may be optically connected to each other. For example, the first optical waveguide S1 and the second optical waveguide 140 may be coupled to each other in a butt-joint manner.

[0066] The first optical waveguide S1 may include an active layer 123. The active layer 123 may have a multi-quantum well (MQW) structure in which well layers and barrier layers are alternately stacked. The compositions of the well layers and the barrier layers may include, but are not limited to, InAlGaAs or InGaAsp.

[0067] The first separated confinement heterostructure (SCH) layer 122 can be an optical waveguide layer for guiding the oscillation of a laser beam, and can be formed, for example, of undoped InAlGaAs or InGaAsP on the first cladding layer 121.

[0068] The second SCH layer 124 can be an optical waveguide layer for guiding the oscillation of a laser beam, and can be formed, for example, of undoped InAlGaAs or InGaAsP on the active layer 123.

[0069] The first SCH layer 122 and the second SCH layer 124 can have a smaller bandgap than the first cladding layer 121 and the second cladding layer 150, and the well layer can have a smaller bandgap than the first SCH layer 123 and the second SCH layer 124. Thus, electrons and holes injected through the first cladding layer 121 and the second cladding layer 150 can be trapped in the quantum well to provide optical gain.

[0070] The first optical waveguide S1 and the second optical waveguide 140 can be disposed between the first cladding layer 121 and the second cladding layer 150. The first cladding layer 121 and the second cladding layer 150 can include, but are not limited to, InP or InGaAsP.

[0071] The grating 131 can be disposed between the second cladding layer 150 and the second SCH layer 124. The grating 131 selects and reflects a single wavelength, thereby achieving single-mode laser output. However, it is not limited thereto, and the grating can be disposed under the first SCH layer 122.

[0072] The ohmic electrode layer 160 and the first electrode 170 can be disposed on the second cladding layer 150. The second electrode 126 can be disposed under the substrate 110.

[0073] Reference Figure 4 and Figure 5 According to an embodiment, the laser element can include the second cladding layer 150 in a strip shape. The waveguide mode occurs in a region where the optical waveguide overlaps with the first cladding layer and the second cladding layer, such that the shape of the second cladding layer 150 can correspond to the waveguide mode region.

[0074] The second cladding layer 150 can include a first sub-cladding layer 151 disposed on the active layer 123 and a second sub-cladding layer 152 disposed on the regenerative passive region. The end 152a of the second sub-cladding layer 152 can be formed to have a narrower width toward the front to have an SSC structure. With this structure, the size of the laser beam to be output can be adjusted.

[0075] According to an embodiment, the laser element may include dummy clads 154 and 153 that are separately provided from the second cladding layer 150 and the first electrode 170. The dummy clads 154 and 153 may have the same composition as the second cladding layer 150. For example, the dummy clads 154 and 153 and the second cladding layer 150 may include InP or InGaAsP.

[0076] The dummy clads 154 and 153 may include a first dummy clad 154 and a second dummy clad 153. The first dummy clad 154 may be disposed on one side of the first electrode 170, and the second dummy clad 153 may be disposed on the other side of the first electrode 170. In other words, the first electrode 170 may be disposed between the first dummy clad 154 and the second dummy clad 153. However, it is not limited thereto, and the first electrode 170 may not be disposed between the first dummy clad 154 and the second dummy clad 153. Only either the first dummy clad 154 or the second dummy clad 153 may be present in the laser element.

[0077] The second cladding layer 150, the first dummy clad 154, and the second dummy clad 153 may have the same thickness. This is because the second cladding layer 150, the first dummy clad 154, and the second dummy clad 153 are grown through the same process and separated by etching.

[0078] The area of the first dummy clad 154 may be different from the area of the second dummy clad 153. For example, the area of the first dummy clad 154 may be larger than the area of the second dummy clad 153. According to this structure, even when the cutting position of the chip changes due to processing errors, the desired SSC width can be maintained, thereby improving the yield. This will be described in detail later.

[0079] The width W11 of the first dummy clad 154 may be equal to the maximum width W3 of the second cladding layer 150, and the width W21 of the second dummy clad 153 may be equal to the minimum width W4 of the second cladding layer 150. The minimum width W4 of the second cladding layer 150 may be smaller than the maximum width W3 of the second cladding layer 150 to adjust the size of the laser beam. Here, the width may be Figure 5 the vertical length in.

[0080] The length W12 of the first dummy clad 154 may be equal to the length W22 of the second dummy clad 153, but it is not limited thereto. For example, the length W12 of the first dummy clad 154 may be greater than or less than the length W22 of the second dummy clad 153. Here, the length may be Figure 5 the horizontal length in.

[0081] Refer to Figure 6, the virtual cladding may include a first virtual cladding 154a disposed at the first corner, a second virtual cladding 153a disposed at the second corner, a third virtual cladding 154a disposed at the fourth corner, and a fourth virtual cladding 153a disposed at the third corner.

[0082] The first virtual cladding 154a and the third virtual cladding 154a may have the same width, and the second cladding 153a and the fourth virtual cladding 153a may have the same width.

[0083] The width of the first virtual cladding 154a may be half of the width of the other end 152b of the second cladding layer 150, and the width of the second virtual cladding 153a may be half of the width of one end 152a of the second cladding layer 150. However, the present disclosure is not necessarily limited thereto. In other words, the width may be greater than or less than half.

[0084] Figures 7 to 15 is a view showing a method for manufacturing a laser element according to an embodiment of the present disclosure. Figure 16 is a plan view showing a state in which a plurality of chip regions are cut on a substrate in a method for manufacturing a laser element according to an embodiment of the present disclosure. Figure 17 is a plan view of a cut chip.

[0085] Referring to Figure 7 , the first cladding layer 121, the first SCH layer 122, the active layer 123, the second SCH layer 124, and the grating layer 130 may be sequentially formed on the substrate 110. A buffer layer may be further formed between the substrate 110 and the first cladding layer 121, but is not limited thereto.

[0086] The active layer 123 may have a MQW structure in which well layers and barrier layers are alternately stacked. The compositions of the well layers and the barrier layers may include, but are not limited to, InAlGaAs or InGaAsP.

[0087] The first SCH layer 122 may be an optical waveguide layer for guiding the oscillation of a laser beam, and may be formed of, for example, undoped InAlGaAs or InGaAsP on the first cladding layer 121.

[0088] The second SCH layer 124 may be an optical waveguide layer for guiding the oscillation of a laser beam, and may be formed of, for example, undoped InAlGaAs or InGaAsP on the active layer 123.

[0089] The first SCH layer 122 and the second SCH layer 124 may have a smaller bandgap than the first cladding layer 121 and the second cladding layer 150, and the well layer may have a smaller bandgap than the first SCH layer 123 and the second SCH layer 124. Thus, electrons and holes injected through the first cladding layer 121 and the second cladding layer 150 can be trapped in the quantum well to provide optical gain.

[0090] Referring Figure 8 , the grating layer 130 may be patterned to form a plurality of gratings 131. The plurality of gratings 131 may select and reflect a single wavelength, thereby achieving single-mode laser output. However, it is not limited thereto, and the grating 131 may be disposed under the first cladding layer 121.

[0091] Referring Figure 9 , a mask 132 may be formed on the plurality of gratings 131. The mask 132 may include, but is not limited to, SiO2 or SiNx. The mask 132 may have, but is not limited to, a parallelogram shape having two inclined surfaces.

[0092] Referring Figure 10 , the first optical waveguide S1 may partially etch WE1. Thus, only the region of the first optical waveguide S1 located under the mask 132 may be retained. Thus, the surfaces S11 and S12 of the first optical waveguide S1 may be inclined according to the shape of the mask 132.

[0093] Referring Figure 11 , the second optical waveguide 140 may be formed in the region where the first optical waveguide S1 is removed. The second optical waveguide 140 may be formed to completely surround the first optical waveguide S1 having a rectangular shape. The second optical waveguide 140 may have a smaller bandgap than the cladding layer. For example, the composition of the second optical waveguide 140 may include, but is not limited to, InGaAsP.

[0094] Referring Figure 12 , the second cladding layer 150 may be formed on the first optical waveguide S1 and the second optical waveguide 140. The ohmic electrode layer 160 may be formed on the second cladding layer 150.

[0095] Referring Figure 13 , the second cladding layer 150 may be etched. In this case, the cross-section of the remaining second cladding layer 150 may have a vertical shape, which is a rectangular shape. However, it is not necessarily limited thereto, and the cross-section may have a ridge shape with a width narrowing towards its lower part. When the cross-section of the second cladding layer 150 has a ridge shape, the virtual cladding may also have a ridge shape.

[0096] The width of the first sub-cladding layer 151 of the second cladding layer 150 is constant, while the second sub-cladding layer 152 may have an SSC structure having a width that gradually narrows towards the light-emitting surface.

[0097] Figure 13 A structure is shown in which the second optical waveguide 140 is exposed through the entire etching of the second cladding layer 150, but is not limited thereto. The structure may be a buried heterodyne (BH) structure, in which after etching the second cladding layer 150, both sides of the second cladding layer 150 are regrown.

[0098] Referring to Figure 14 and Figure 15 , a planarization layer 180 and a protective layer 171 may be formed in the region where the second cladding layer 150 is etched, and a first electrode 170 contacting the ohmic electrode layer 160 may be formed. The protective layer 171 may be disposed on the first optical waveguide and the second optical waveguide, which are exposed by etching the second cladding layer 150. The protective layer 171 may be disposed on the virtual cladding.

[0099] Referring to Figure 16 , a method of manufacturing a laser element according to an embodiment may form an epitaxial layer (epi) and electrodes on a wafer substrate, and then separate the wafer substrate into a plurality of chip unit regions 11 to 22. In other words, as shown in Figures 7 to 11 , a first cladding layer, a first optical waveguide, and a second optical waveguide may be sequentially formed on the wafer substrate.

[0100] A plurality of first optical waveguides S1 divided by etching (see Figure 10 ) may be alternately arranged with each other in a first direction (Y-axis direction). For example, the first optical waveguide S1 disposed in the first chip unit region 11 may be alternately disposed with the first optical waveguide S1 disposed in the third chip unit region 13 in the first direction (Y-axis direction). In addition, the first optical waveguide S1 disposed in the first chip unit region 11 may be disposed to face the first optical waveguide S1 disposed in the sixth chip unit region 16. In other words, a plurality of first optical waveguides S1 may be arranged in a zigzag pattern in the first direction.

[0101] A first region L1 between the first optical waveguide S1 disposed in the first chip unit region 11 and the first optical waveguide S1 disposed in the sixth chip unit region 16 may have the same distance as a second region L2 between the first optical waveguide S1 disposed in the sixth chip unit region 16 and the first optical waveguide S1 disposed in the twentieth chip unit region 21. Therefore, the intervals between the first optical waveguides S1 facing each other in the first direction (Y-axis direction) may be equal.

[0102] The first region L1 and the second region L2 may be regions where the second optical waveguide is regrown. Therefore, since the areas of the regions where the second optical waveguide is regrown are equal to each other, the thickness and composition may become uniform.

[0103] Referring to Figure 17 , in the sixth chip unit region 16, the composition and thickness of the passive optical waveguide 141 disposed in front of the first optical waveguide S1 may be the same as those of the passive optical waveguide 142 disposed at the rear of the first optical waveguide S1. Accordingly, the quality of the light emitting surface AR and the light reflecting surface HR disposed in the passive optical waveguide becomes uniform, improving the reflection and light emitting performance.

[0104] Referring to Figure 16 , a plurality of second cladding layers 150 may be respectively disposed in the chip unit regions 11 to 22 by mesa etching. The plurality of second cladding layers 150 may be disposed to overlap with the first optical waveguide S1.

[0105] The plurality of second cladding layers 150 may be disposed at intervals from each other in the first direction (longitudinal direction). In other words, the plurality of second cladding layers 150 may not be continuously disposed in the longitudinal direction, but may be alternately disposed in a staggered manner. The structure in which the plurality of second cladding layers 150 are alternately disposed in the first direction (Y-axis direction) may be the same as the structure of the first optical waveguide S1.

[0106] In this case, the length of the second cladding layer 150 formed in the longitudinal direction is longer than the length of the chip unit region. For example, the end 153 of the second cladding layer 150 disposed in the sixth chip unit region 16 may be formed to be long so as to extend to the eighth chip unit region 18, and the other end 154 of the second cladding layer 150 disposed in the sixth chip unit region 16 may be formed to be long so as to extend to the third chip unit region 13. With this structure, even when the second cladding layer 150 is divided into longer or shorter due to tolerance, a desired width can be maintained, thereby preventing a reduction in the yield.

[0107] In the chip dicing process, the chip may be mainly diced along the second direction dicing lines C1, C2, C11, and C12 and diced along the first direction dicing lines C3 to C8, thereby allowing separation of the chip units. In this case, even when the dicing deviates from the second direction dicing lines C1, C2, C11, and C12 due to tolerance, both ends of the second cladding layer 150 extend beyond the chip unit regions 11 to 17, so that the width of the second cladding layer 150 can be maintained, increasing the yield. Accordingly, as Figure 17 shown, when the chips are completely separated, the remaining portions 153 and 154 of the adjacent second cladding layers 150 may remain in the chips.

[0108] Figure 18 is a plan view showing a state in which a plurality of chip regions are diced on a substrate in a method for manufacturing a laser element according to another embodiment of the present disclosure. Figure 19 is a plan view of a diced chip.

[0109] As described above, the first optical waveguide S1 and the second cladding layer 150 are alternately arranged with each other, but in Figure 18 the two adjacent second cladding layers 150 can be arranged to overlap each other in one chip unit area. Thus, as Figure 19 shown, by cutting the chip, virtual claddings 153a and 154a can be formed in each of the four corners.

[0110] More specifically, the virtual claddings 153a and 154a can include a first virtual cladding 154a disposed at the first corner VX1, a second virtual cladding 153a disposed at the second corner VX2, a third virtual cladding 154a disposed at the fourth corner VX4, and a fourth virtual cladding 153a disposed at the third corner VX3.

[0111] The first virtual cladding 154a and the third virtual cladding 154a can have the same width, and the second cladding layer 153a and the fourth virtual cladding 153a can have the same width.

[0112] The width of the first virtual cladding 154a can be half of the width of the other end 152b of the second cladding layer 150, and the width of the second virtual cladding 153a can be half of the width of one end 152a of the second cladding layer 150.

[0113] Figure 20 is a plan view showing a state in which a plurality of chip unit areas are cut on a substrate in a method for manufacturing a laser element according to still another embodiment of the present disclosure. Figure 21 is a plan view of a cut chip.

[0114] In accordance with Figure 20 the structure used in the state in which a plurality of chip areas are cut as shown, the difference is that a plurality of cladding layers 150 are arranged to face each other. Figure 16 For example, the second cladding layer 150 in the first chip unit layer 11 and the second chip unit area 12 may have an SSC structure 153 in the first direction, while the second cladding layer 150 provided in the third chip unit area to the fifth chip unit area 13, 14, and 15 may have an SSC structure 153 in the direction opposite to the first direction.

[0115]

[0116] Therefore, as Figure 21 shown, the width of the virtual cladding 153 connected to the light emitting surface AR can be smaller than the width of the virtual cladding 154 connected to the light reflecting surface HR.

[0117] Figure 22 ​It is a plan view showing a state in which a plurality of chip unit regions are cut on a substrate in a method for manufacturing a laser element according to still another embodiment of the present disclosure. Figure 23 It is a plan view of a cut chip.

[0118] In accordance with Figure 22 the structure shown in which a plurality of chip regions are cut, a state is used in which Figure 18 a plurality of cladding layers 150 are arranged to face each other. For example, the second cladding layer 150 in the first chip unit layer 11 and the second chip unit region 12 may have an SSC structure in the first direction, while the second cladding layer 150 provided in the third chip unit region to the fifth chip unit regions 13, 14, and 15 may have an SSC structure 153 in a direction opposite to the first direction.

[0119] Therefore, as Figure 23 shown, the width of the virtual cladding 153a connected to the light-emitting surface AR may be smaller than the width of the virtual cladding 154a connected to the light-reflecting surface HR.

[0120] Although the embodiments have been described above, these embodiments are merely examples and do not limit the present disclosure, and those of ordinary skill in the art should understand that various modifications and applications not described above are possible without departing from the basic features. For example, each component described in detail in the embodiments can be modified. The differences related to such modifications and applications should be construed as falling within the scope of the present disclosure defined by the claims.

Claims

1. A laser element, comprising: A first cladding layer; An optical waveguide disposed on the first cladding layer; A second cladding layer disposed on the optical waveguide; A first electrode disposed on the second cladding layer; And A virtual cladding disposed on the optical waveguide and separated from the second cladding layer and the first electrode; Wherein, in the thickness direction of the virtual cladding, the virtual cladding and the active layer of the optical waveguide do not overlap each other; Wherein, the virtual cladding has the same composition and thickness as the second cladding layer; Wherein, the virtual cladding is a part of the second cladding layer of adjacent laser elements cut out when cutting the laser elements.

2. The laser element according to claim 1, wherein The virtual cladding includes a first virtual cladding and a second virtual cladding, and The area of the first virtual cladding is larger than the area of the second virtual cladding.

3. The laser element according to claim 2, wherein The thickness of the second cladding layer, the thickness of the first virtual cladding, and the thickness of the second virtual cladding are equal to each other.

4. The laser element according to claim 2, wherein The length of the first virtual cladding is equal to the length of the second virtual cladding.

5. The laser element according to claim 2, wherein The first electrode is disposed between the first virtual cladding and the second virtual cladding.

6. The laser element according to claim 2, wherein The composition of the first virtual cladding and the second virtual cladding is the same as the composition of the second cladding layer.

7. The laser element according to claim 2, wherein The width of the first virtual cladding is equal to the maximum width of the second cladding layer, and The width of the second virtual cladding is equal to the minimum width of the second cladding layer.

8. The laser element according to claim 1, wherein The virtual cladding includes a first virtual cladding disposed at a first corner, a second virtual cladding disposed at a second corner, a third virtual cladding disposed at a fourth corner, and a fourth virtual cladding disposed at a third corner; The first virtual cladding and the third virtual cladding have the same width, and The second virtual cladding and the fourth virtual cladding have the same width.

9. The laser element according to claim 8, wherein The width of the first virtual cladding is half of the maximum width of the optical waveguide, and The width of the second virtual cladding is half of the minimum width of the optical waveguide.

10. The laser element according to claim 1, wherein The optical waveguide includes a first optical waveguide and a second optical waveguide surrounding the first optical waveguide.

11. The laser element according to claim 1, wherein The second cladding layer is formed to have a width decreasing in one direction.

12. A method for manufacturing a laser element, the method comprising: Forming a first optical waveguide on a first cladding layer; Forming a second optical waveguide on the first cladding layer; Forming a second cladding layer on the first optical waveguide and the second optical waveguide; Dividing the second cladding layer into a plurality of second cladding layers by etching the second cladding layer; And Performing cutting to form a plurality of chips. Among them, the formation of the second optical waveguide includes dividing the first optical waveguide into a plurality of first optical waveguides by etching the first optical waveguide, and forming the second optical waveguide in the region where the first optical waveguide is etched. The plurality of first optical waveguides are alternately arranged in the longitudinal direction of the second cladding layer. When cutting is performed to form a plurality of chips, a portion cut from the second cladding layer of adjacent chips is formed as a virtual cladding on each chip. Among them, in the thickness direction of the virtual cladding, the virtual cladding and the active layer of the first optical waveguide do not overlap each other.

13. The method according to claim 12, wherein The dividing into a plurality of second cladding layers includes dividing the second cladding layer into a plurality of second cladding layers by etching the second cladding layer, and the plurality of second cladding layers are respectively disposed on the plurality of first optical waveguides.

14. The method according to claim 13, wherein The plurality of second cladding layers are alternately arranged in the longitudinal direction.

15. The method according to claim 13, wherein The plurality of second cladding layers are respectively disposed in a plurality of chip unit regions, and Both ends of the second cladding layer extend to the outside of the chip unit region.

16. The method according to claim 13, wherein In the step of performing cutting to form the plurality of chips, the chips are separated such that when both ends of the plurality of second cladding layers are cut in a direction perpendicular to the longitudinal direction of the second cladding layer, they are partially cut.

17. The method according to claim 12, wherein The forming of the plurality of second cladding layers includes forming the plurality of second cladding layers such that the width of the end portion of the second cladding layer becomes narrower.

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