Semiconductor laser device

Abstract

A semiconductor laser element includes a substrate; a stacked structure located on the substrate and including a first semiconductor layer, an active layer, and a second semiconductor layer having a ridge structure, and the stacked structure having a first end face; a first scriber channel adjacent to the first end face and extending from a top surface of the stacked structure toward the substrate to expose a first scriber surface of the substrate; and a separation channel located on one side of the stacked structure, adjoining or overlapping the first scriber channel, and extending from the top surface of the stacked structure toward the substrate to expose the substrate, wherein the separation channel includes a first region exposing a first upper surface of the substrate, a second region exposing a second upper surface of the substrate, and a third region exposing a third upper surface of the substrate. The first region includes a first depth between the top surface and the first upper surface of the stacked structure, the second region includes a second depth between the top surface and the second upper surface of the stacked structure, and the third region includes a third depth between the top surface and the third upper surface of the stacked structure. The first region is closer to the first end face than the second region, the second region is closer to the first end face than the third region, the first depth is greater than the second depth, and the second depth is approximately the same as the third depth.

Description

Technical Field

[0001] The present invention relates to a light emitting element, and in particular to a semiconductor laser element. Prior Art

[0002] In recent years, the demand for and application of semiconductor laser devices has become increasingly widespread. Laser scribing of epitaxial wafers is often used to form the scribe trenches required for cleaving individual laser devices. However, the spatter generated by laser scribing can contaminate the laser device. Therefore, there is an urgent need for an improved semiconductor laser device that reduces the risk of contamination from film spatter. Summary of the Invention

[0003] The present invention relates to a semiconductor laser element, in particular to a semiconductor laser element which can reduce the contamination of the light-emitting surface of the optical resonator by splashes during the laser scribing process.

[0004] According to one embodiment of the present invention, a semiconductor laser device includes a substrate; a stacked structure disposed on the substrate and sequentially including a first semiconductor layer, an active layer, and a second semiconductor layer along a stacking direction, wherein the second semiconductor layer has a ridge structure. The stacked structure has a first end surface; a first scribe line trench adjacent to the first end surface extends from a top surface of the stacked structure toward the substrate to expose a first scribe line surface of the substrate; and a separation trench disposed on one side of the stacked structure, contacting or overlapping with the first scribe line trench, and extending from the top surface of the stacked structure toward the substrate to expose the substrate. The separation trench includes a first region exposing a first upper surface of the substrate, a second region exposing a second upper surface of the substrate, and a third region exposing a third upper surface of the substrate. The first region includes a first depth D1 located between the top surface of the stacked structure and the first upper surface of the substrate, the second region includes a second depth D2 located between the top surface of the stacked structure and the second upper surface of the substrate, and the third region includes a third depth D3 located between the top surface of the stacked structure and the third upper surface of the substrate. When viewed from above, the first region is closer to the first end surface than the second region, and the second region is closer to the first end surface than the third region, so that the first depth D1 is greater than the second depth D2, and the second depth D2 is approximately the same as the third depth D3.

[0005] In order to better understand the above and other aspects of the present invention, the following embodiments are specifically described in detail with reference to the accompanying drawings: Simple diagram description

[0006] FIG1 is a top view of a semiconductor laser device according to an embodiment of the present invention.

[0007] FIG2 is a cross-sectional view of a semiconductor laser device along the A1 - A1 ′ line of FIG1 according to an embodiment of the present invention.

[0008] FIG3 is a cross-sectional view of a semiconductor laser device along the A2 - A2 ′ line of FIG1 according to an embodiment of the present invention.

[0009] FIG4 is a cross-sectional view of a semiconductor laser device along the A3 - A3 ′ line of FIG1 according to an embodiment of the present invention.

[0010] FIG5 is a cross-sectional view taken along the BB′ line of FIG1 according to one embodiment of the present invention.

[0011] FIG. 6A is a schematic diagram illustrating separation trenches, first scribe trenches, and second scribe trenches exposing the top surface of a substrate according to an embodiment of the present invention.

[0012] FIG. 6B is a schematic diagram illustrating separation trenches, first scribe trenches, and second scribe trenches exposing the surface of the substrate according to an embodiment of the present invention.

[0013] FIG. 7 is a top view of a semiconductor laser device rod according to an embodiment of the present invention.

[0014] FIG8A is a cross-sectional view taken along the CC′ section line of FIG7 .

[0015] FIG8B is a cross-sectional view taken along the DD′ section line of FIG7 .

[0016] FIG8C is a cross-sectional view taken along the EE′ section line of FIG7 .

[0017] FIG8D is a cross-sectional view of a modified embodiment taken along the EE′ section line of FIG7 .

[0018] 9A to 9J illustrate a manufacturing process flow of a semiconductor laser device according to an embodiment of the present invention.

[0019] FIG. 10 is a cross-sectional view of a laser diode device according to an embodiment of the present invention. Implementation Method

[0020] The present invention provides a semiconductor laser device that can address the problem of spatter generated during laser scribing contaminating the light-emitting or reflective surfaces of the wafer, thereby affecting the light output of the optical resonator and causing yield loss. To better understand the objectives, features, and advantages of the present invention, several embodiments are described below with accompanying drawings for detailed explanation.

[0021] However, it should be noted that these specific embodiments and methods are not intended to limit the present invention. The present invention may be implemented using other features, components, methods, and parameters. The preferred embodiments are merely illustrative of the technical features of the present invention and are not intended to limit the scope of the present invention. Those skilled in the art of the present invention will be able to make equivalent modifications and variations based on the following description without departing from the spirit of the present invention.

[0022] FIG1 illustrates a top view of a semiconductor laser device 100 according to an embodiment of the present invention, wherein FIG1 corresponds to a plane formed by the X and Y directions. FIG2 illustrates a cross-sectional view of the semiconductor laser device 100 along line A1-A1' in FIG1 according to an embodiment of the present invention. FIG3 illustrates a cross-sectional view of the semiconductor laser device 100 along line A2-A2' in FIG1 according to an embodiment of the present invention. FIG4 illustrates a cross-sectional view of the semiconductor laser device 100 along line A3-A3' in FIG1 according to an embodiment of the present invention. FIG5 illustrates a cross-sectional view along line BB' in FIG1 according to an embodiment of the present invention. FIG2, FIG3, and FIG4 correspond to planes formed by the X and Z directions, respectively. FIG5 corresponds to a plane formed by the Y and Z directions. The X, Y, and Z directions represent three different directions, which may be perpendicular to each other, but the present invention is not limited thereto.

[0023] Referring simultaneously to Figures 1, 2, 3, and 4, a semiconductor laser device 100 includes a substrate 110, a stacked structure 120 including a ridge structure 122R on the substrate 110, a separation trench 130 on one side of the stacked structure 120, a first scribe trench 131 connected to the separation trench 130, and a second scribe trench 170 within the separation trench 130, although the present invention is not limited thereto. Figures 3 and 4 illustrate that the semiconductor laser device 100 further includes a top electrode 140, a bottom electrode 150, and a protective layer 160 between the top electrode 140 and the stacked structure 120. As shown in Figure 1, the semiconductor laser device 100 has a device length 100L and a device width 100W. As shown in Figure 5, the semiconductor laser device 100 has a device height 100H. The device length 100L of the semiconductor laser device 100 can be 840 μm to 1560 μm, 960 μm to 1440 μm, or 1080 μm to 1212 μm. The device width 100W of the semiconductor laser device 100 can be 130 μm to 260 μm, 160 μm to 240 μm, or 180 μm to 220 μm. The device height 100H can be 70 μm to 120 μm. The separation trench 130 includes a separation trench width 130W that can be 2 μm to 20 μm, 5 μm to 15 μm, or 7 μm to 13 μm. The separation trench 130 includes a separation trench length 130L that can be 840 μm to 1560 μm, 960 μm to 1440 μm, or 1080 μm to 1212 μm. In some embodiments, the second scribe trench 170 includes a second scribe trench length 170L that is less than the separation trench length 130L. The second scribe trench 170 includes a second scribe trench width 170W that can be 1 μm to 9 μm, 3 μm to 7 μm, or 4 μm to 6 μm.

[0024] The substrate 110 has an upper surface 110a and a lower surface 110b. The upper surface 110a is located on opposite sides of the substrate 110 relative to the lower surface 110b. The substrate 110 has a first side s1 and a second side s2 that are opposite to each other. The first side s1 and the second side s2 may be parallel to each other. Furthermore, the substrate 110 has a third side s3 and a fourth side s4, and the third side s3 and the fourth side s4 are not parallel to the first side s1 or the second side s2, respectively. The upper surface 110a and the lower surface 110b are connected to each other via the first side s1 or the third side s3, or via the second side s2 or the third side s3. In this embodiment, when viewed from above in the XY plane, the semiconductor laser device 100 has a rectangular shape, such as a rectangle. For example, the first side s1 or the second side s2 is shorter than the third side s3 or the fourth side s4, and the first side s1 or the second side s2 is perpendicular to and adjacent to the third side s3 or the fourth side s4, respectively. However, the present invention is not limited thereto.

[0025] In some embodiments, substrate 110 is, for example, a silicon substrate, a nitride-based semiconductor substrate, a silicon carbide substrate, or a gallium arsenide substrate. In one embodiment, substrate 110 may be further thinned or patterned. For example, lower surface 110b of substrate 110 may be a roughened surface after patterning, but the present invention is not limited thereto. In one embodiment, substrate 110 comprises a III-V semiconductor material, such as gallium nitride (GaN) or other suitable materials, as represented by the general formula InxAlyGa1-x-yN (0≦x, 0≦y, x+y≦1). The upper surface 110a of the substrate 110 may include a (0001) plane, a (000-1) plane, a (10-10) plane, a (11-20) plane, a (10-14) plane, a (10-15) plane, or a (11-24) plane. In this embodiment, the (0001) plane is used as the epitaxial growth surface of the stacked structure 120. The thickness of the substrate 110 may be between 70 microns and 120 microns. In some embodiments, the substrate 110 may be n-type gallium nitride (GaN) and serves as part of the current path of the semiconductor laser device 100.

[0026] In some embodiments, the separation trench 130 of the semiconductor laser device 100 exposes the top surface 110a of the substrate 110. The top surface 110a includes a first top surface 110a-1 located in a first region 130-1 of the separation trench 130, a second top surface 110a-2 located in a second region 130-2 of the separation trench 130, and a third top surface 110a-3 located in a third region 130-3 of the separation trench 130. One of the first top surface 110a-1, the second top surface 110a-2, and the third top surface 110a-3 may be located at the same or different levels as the other top surfaces, or the first top surface 110a-1, the second top surface 110a-2, and the third top surface 110a-3 may all be located at different levels. For example, the first upper surface 110a-1 is closer to the lower surface 110b of the substrate 110 than the second upper surface 110a-2 and the third upper surface 110a-3, and the second upper surface 110a-2 and the third upper surface 110a-3 are located on the same or different horizontal planes.

[0027] As shown in FIG2 , the first region 130-1 comprises a first depth D1 located between a top surface 122T and the first upper surface 110a-1. As shown in FIG3 , the second region 130-2 comprises a second depth D2 located between the top surface 122T and the second upper surface 110a-2. As shown in FIG4 , the third region 130-3 comprises a third depth D3 located between the top surface 122T and the third upper surface 110a-3. In one embodiment, the first depth D1, the second depth D2, and the third depth D3 may be the same, but this is not a limitation. In another embodiment, the first depth D1, the second depth D2, and the third depth D3 may be different, for example, the first depth D1 may be greater than the second depth D2, or the second depth D2 and the third depth D3 may be substantially the same or different, but this is not a limitation. The first depth D1 may be 12 μm to 35 μm, 18 μm to 30 μm, or 20 μm to 28 μm. The second depth D2 can be 0.1 μm to 10 μm, 2 μm to 8 μm, or 3 μm to 5 μm. The third depth D3 can be 0.1 μm to 10 μm, 2 μm to 8 μm, or 3 μm to 5 μm. In one embodiment, the first depth D1, the second depth D2, and the third depth D3 are not limited to being measured from the top surface of the stacked structure 120; they can also be measured from the top surface of the conductive contact layer 124 or the top electrode 140. In other words, the top surface 122T can be the top surface of the stacked structure 120, the top surface of the conductive contact layer 124, or the top surface of the top electrode 140. In one embodiment, the first depth D1, the second depth D2, and the third depth D3 in Figures 2 to 4 are measured based on the maximum distance parallel to the Z direction.

[0028] In some embodiments, as shown in FIG. 1 , the first scribe trench 131 of the semiconductor laser device 100 is adjacent to or partially overlaps the separation trench 130 . Two first scribe trenches 131 adjacent to the first side s1 are spaced apart to prevent damage to the light-emitting surface. For example, the spacing may be 90 μm to 170 μm, 100 μm to 160 μm, or 110 μm to 150 μm. As shown in FIG. 2 , the first scribe trench 131 has a first scribe depth d1 to expose the substrate 110, such that the upper surface 110a of the substrate 110 further includes a first scribe surface 110c located above the first scribe trench 131. In some embodiments, the first scribe depth d1 is located between the top surface 122T and the first scribe surface 110c, and is less than or equal to the first depth D1. In some embodiments, the first scribe surface 110c and the first upper surface 110a-1 may be coplanar. In some embodiments, a first step H1 exists between the first scribe line surface 110c and the first upper surface 110a-1, and they are not located on the same horizontal plane. The first step H1 is substantially the same as the second depth D2 and / or the third depth D3. For example, the first step H1 can be 0.1 μm to 10 μm, 2 μm to 8 μm, or 3 μm to 5 μm. In one embodiment, the first scribe line depth d1 and the first step H1 are measured based on the maximum distance parallel to the Z direction.

[0029] In some embodiments, as shown in FIG. 1 , the second scribe trench 170 of the semiconductor laser device 100 is adjacent to, partially overlaps, or completely overlaps with the separation trench 130. As shown in FIG. 4 , the second scribe trench 170 includes a second scribe depth d2 to expose the substrate 110, such that the upper surface 110a of the substrate 110 further includes a second scribe surface 110a-4 exposed within the second scribe trench 170. In some embodiments, as shown in FIG. 4 , the second scribe depth d2 is located between the second scribe surface 110a-4 and the third upper surface 110a-3 or between the second scribe surface 110a-4 and the second upper surface 110a-2 (not shown), and the second scribe depth d2 is greater than the second depth D2 and / or the third depth D3. In some embodiments, the second scribe surface 110a-4 is not located on the same horizontal plane as the second upper surface 110a-2 and / or the third upper surface 110a-3. In some embodiments, the second scribe line surface 110a-4 and the third upper surface 110a-3 may be parallel to each other, or the second scribe line surface 110a-4 may include an inclined surface that is not parallel to the third upper surface 110a-3. In one embodiment, the second scribe line depth d2 is measured as the maximum distance parallel to the Z direction.

[0030] The stacked structure 120 is located on the upper surface 110a of the substrate 110 and includes, in order from the upper surface 110a of the substrate 110 along the Z direction (the stacking direction), a first semiconductor layer 121, an active layer 123, and a second semiconductor layer 122. The first semiconductor layer 121 is made of an n-type semiconductor material, such as an n-type nitride semiconductor material. In one embodiment, the first semiconductor layer 121 comprises an n-type nitride semiconductor layer doped with a first dopant. The second semiconductor layer 122 is made of a p-type semiconductor material, such as a p-type nitride semiconductor material. In one embodiment, the second semiconductor layer 122 comprises a p-type nitride semiconductor layer doped with a second dopant, but the present invention is not limited thereto. The p-type semiconductor layer having the second dopant is, for example, a nitride-based semiconductor layer doped with elements such as magnesium (Mg), lithium (Li), sodium (Na), potassium (K), beryllium (Be), zinc (Zn), or calcium (Ca). The n-type semiconductor layer having the first dopant is, for example, a nitride-based semiconductor layer doped with elements such as silicon (Si), carbon (C), germanium (Ge), tin (Sn), lead (Pb), or oxygen (O). The nitride-based semiconductor layer is represented by the general formula InxAlyGa1-x-yN (0≦x, 0≦y, x+y≦1). In one embodiment, the stacked structure 120 includes a contact layer (not shown) located on the second semiconductor layer 122. The contact layer may be a p-type nitride semiconductor layer having the second dopant. The doping concentration of the second dopant in the contact layer may be greater than the doping concentration of the second semiconductor layer 122. In one embodiment, the doping concentration of the second dopant in the contact layer is greater than 1×10 20 cm -3 , and the doping concentration of the second semiconductor layer 122 is between 5×10 17 cm -3 and 5×10 19 cm -3 , although the present invention is not limited thereto. The active layer 123 may be doped or undoped. The doping concentration of the first dopant in the first semiconductor layer 121 is between 1×10 18 cm -3 and 2×10 19 cm -3 . The active layer 123 may be a compound semiconductor of two elements from the III-V group, such as gallium arsenide (GaAs), indium phosphide (InP), gallium phosphide (GaP), or gallium nitride (GaN); a multi-element compound semiconductor from the III-V group, such as aluminum gallium arsenide (AlGaAs), indium gallium nitride (InGaN), aluminum gallium nitride (AlGaN), aluminum indium gallium nitride (AlInGaN), gallium arsenide phosphide (GaAsP), aluminum gallium indium phosphide (AlGaInP), or aluminum indium gallium arsenide (AlInGaAs); or a compound semiconductor of two elements from the II-VI group, such as cadmium selenide (CdSe), cadmium sulfide (CdS), or zinc selenide (ZnSe), but the present invention is not limited thereto.

[0031] As shown in Figures 2 to 5 , the first semiconductor layer 121 has a first length 121L and a first width 121W. The first length 121L of the first semiconductor layer 121 can be 840 to 1560 microns, 960 to 1440 microns, or 1080 to 1212 microns. The first width 121W of the first semiconductor layer 121 can be 140 to 260 microns, 160 to 240 microns, or 180 to 220 microns. The second semiconductor layer 122 has a second length 122L and a second width 122W. The second length 122L of the second semiconductor layer 122 can be 840 to 1560 microns, 960 to 1440 microns, or 1080 to 1212 microns. The second width 122W of the second semiconductor layer 122 may be 140 μm to 260 μm, 160 μm to 240 μm, or 180 μm to 220 μm.

[0032] The second semiconductor layer 122 includes a ridge structure 122R protruding from the stacking direction. The ridge structure 122R can form an optical resonator. The ridge structure 122R is substantially parallel to the Y direction when viewed from above in the XY plane. It is arranged in a rectangular shape, extending along the long side of the semiconductor laser device 100. For example, it extends from the first side s1 to the second side s2 along a direction parallel to the third side s3 of the substrate 110. It has a ridge width RW, a ridge length RL, and a ridge height RH. The ridge length RL of the ridge structure 122R can be 840 μm to 1560 μm, 960 μm to 1440 μm, or 1080 μm to 1212 μm. The ridge width RW of the ridge structure 122R can be 35 μm to 65 μm, 40 μm to 60 μm, or 45 μm to 55 μm. The ridge height RH of the ridge structure 122R may be between 315 nm and 385 nm, between 280 nm and 420 nm, or between 245 nm and 455 nm.

[0033] The longitudinal mode characteristics of a semiconductor laser device are related to the geometric properties of the optical resonator. In some embodiments, when the semiconductor laser device 100 outputs light in a multiple-mode mode, the ridge width RW of the ridge structure 122R can be greater than 5 microns, the device length 100L can range from 840 microns to 1560 microns, and the device width 100W can range from 130 microns to 260 microns. In some embodiments, when the semiconductor laser device 100 outputs light in a single-mode mode, the ridge width RW of the ridge structure 122R can be less than 5 microns, the device length 100L can range from 120 microns to 660 microns, and the device width 100W can range from 100 microns to 200 microns.

[0034] In some embodiments, the semiconductor laser device 100 includes a conductive contact layer 124 located on the stacked structure 120. The conductive contact layer 124 may be made of at least one of a light-transmitting conductive oxide such as indium tin oxide (ITO), zinc oxide (ZnO), zinc indium tin oxide (ZITO), zinc indium oxide (ZIO), zinc tin oxide (ZTO), gallium indium tin oxide (GITO), gallium indium oxide (GIO), gallium zinc oxide (GZO), aluminum doped zinc oxide (AZO), or fluorine doped tin oxide (FTO), or a light-transmitting metal layer having a thickness of less than 500 angstroms such as aluminum (Al), nickel (Ni), or gold (Au).

[0035] The ridge structure 122R is formed by at least the upper portion of the second semiconductor layer 122. The ridge structure 122R is formed on the upper portion of the second semiconductor layer 122. As shown in FIG5 , in one embodiment, the conductive contact layer 124 is formed on the second semiconductor layer 122 and is recessed inward from the edge of the stacked structure 120 along the Y direction by a contact distance 124d. The contact distance 124d can be 11.9 μm to 22.1 μm, 13.6 μm to 20.4 μm, or 15.3 μm to 18.7 μm. In one embodiment, the ridge structure 122R is formed by epitaxially forming the stacked structure 120 and then removing a portion of the second semiconductor layer 122 by photolithography and etching. The remaining upper portion of the second semiconductor layer 122 forms the ridge structure 122R. For example, in FIG3 , the ridge structure 122R is shown as the portion protruding from the upper portion of the second semiconductor layer 122.

[0036] The semiconductor laser device 100 includes a first end surface and a second end surface opposite the first end surface. As shown in FIG5 , the first end surface can be a light-emitting end surface 100r or a reflective end surface 100s. When the first end surface is the light-emitting end surface 100r, the second end surface can be the reflective end surface 100s. When the first end surface is the reflective end surface 100s, the second end surface can be the light-emitting end surface 100r. The light-emitting end surface 100r and the reflective end surface 100s are located on opposite sides of the stack structure 120, for example, on opposite sides, and are perpendicular to the upper surface 110a and / or lower surface 110b of the substrate 100.

[0037] The light-emitting end face 100r and the reflective end face 100s of the semiconductor laser device 100 of the present invention are approximately perpendicular to the extension direction of the ridge length RL of the ridge structure 122R, forming a resonant cavity of the optical resonator. Light generated in the active layer 123 resonates back and forth between the light-emitting end face 100r and the reflective end face 100s. The light-emitting end face 100r emits light to the outside, while the reflective end face 100s reflects light into the resonant cavity. Hereinafter, the resonant cavity direction is referred to as the length direction, and the direction perpendicular to the resonant cavity direction is referred to as the width direction.

[0038] In an embodiment of the present invention, in order to make light resonate back and forth between the light output end face 100r and the reflection end face 100s, and make the light emit from the light output end face 100r to the outside, a low reflectivity structure 100ES including a dielectric material can be formed on the light output end face 100r, and a high reflectivity structure 100RS including a dielectric material can be formed on the reflection end face 100s. The low reflectivity structure 100ES can be a single-layer film or a multi-layer film. The high reflectivity structure 100RS can be a multi-layer film, and some of the film layers in the high reflectivity structure 100RS can be the same as the low reflectivity structure 100ES. The dielectric material includes at least one of oxides, nitrides, or oxynitrides selected from aluminum (Al), silicon (Si), niobium (Nb), titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), zinc (Zn), yttrium (Y), gallium (Ga), magnesium (Mg), such as Al xO y (1 < x, 1 < y), SiO x (1 < x), Nb xO y (1 < x, 1 < y), TiO x (1 < x), or ZrO x (1 < x), etc. The low reflectivity structure 100ES has a reflectivity of more than 85%, but lower than the reflectivity of the high reflectivity structure 100RS, and can include metal oxides, such as Al 2O 3, or metal oxynitrides, such as AlNO x. The high reflectivity structure has a reflectivity of more than 90%, for example, more than 95%, can include, for example, multiple pairs of SiO 2 / Ta 2O 5, and includes Al 2O 3 and SiO 2, which are respectively located on both sides of SiO 2 / Ta 2O 5.

[0039] As shown in FIGS. 2 to 4, the upper electrode 140 can be a P-electrode, located on the ridge structure 122R and contacting the conductive contact layer 124 and the protective layer 160. Viewed from above in the XY plane, the upper electrode 140 is, for example, a rectangular structure or a strip-shaped structure extending from the first side s1 to the second side s2 along the direction parallel to the third side s3 or the fourth side s4 of the substrate 110. The upper electrode 140 can partially or completely cover the ridge structure 122R (not shown in the figure), for example, the upper electrode 140 shown in FIG. 1 partially covers the ridge structure 122R. As shown in FIG. 5, the edge of the upper electrode 140 can be at an appropriate distance from the light output end face 100r and the reflection end face 100s, separated from the light output end face 100r and / or the reflection end face 100s, and respectively retract a distance 140d inward along the positive and negative Y directions from the edge of the stacked structure 120. The distance 140d can be 7 micrometers to 13 micrometers, 8 micrometers to 12 micrometers, or 9 micrometers to 11 micrometers.

[0040] In some embodiments, the lower electrode 150 may be an N-electrode located on the lower surface 110b of the substrate 110. The material of the lower electrode 150 or the upper electrode 140 may include palladium (Pd), chromium (Cr), titanium (Ti), aluminum (Al), gold (Au), platinum (Pt), any combination thereof, or other suitable conductive materials, or a composite material formed from multiple conductive materials. In some embodiments, the material of the protective layer 160 may include oxides, nitrides, or oxynitrides of silicon (Si), zirconium (Zr), aluminum (Al), or tantalum (Ta), or other suitable insulating materials. The thickness of the protective layer 160 is not particularly limited. As shown in FIG5 , the lower electrode 150 may be flush with the first side s1 and / or the second side s2 of the substrate 110. In some embodiments, the lower electrode 150 may be recessed inward from the first side s1 and / or the second side s2 by a distance in each of the positive and negative Y directions. This distance may be 7 to 13 microns, for example, 8 to 12 microns or 9 to 11 microns.

[0041] FIG6A is a schematic diagram showing separation trenches 130, first scribe trenches 131, and second scribe trenches 170 exposing the upper surface 110a of the substrate 110 according to one embodiment of the present invention. In order to make other features of the present invention clearer, some elements may be omitted in FIG6A.

[0042] The first region 130-1 of the separation channel 130 exposes the first upper surface 110a-1 of the substrate 110, the second region 130-2 of the separation channel 130 exposes the second upper surface 110a-2 of the substrate 110, and the third region 130-3 of the separation channel 130 exposes the third upper surface 110a-3 of the substrate 110. In some embodiments, a plurality of first scribe lines 131 are respectively located on the light-emitting end surface 100r and the reflective end surface 100s, and extend from the top surface 122T toward the lower surface 110b of the substrate 110 to expose the first scribe line surface 110c of the substrate 110. The separation channel 130 is located on one side of the ridge structure 122R and exposes the substrate 110, or in other words, two separation channels 130 are located on opposite sides of the ridge structure 122R and expose the substrate 110. The separation trenches 130 located on both sides of the ridge structure 122R form a one-to-one or one-to-many connection with the first scribe trenches 131 adjacent to the first side s1 and the second side s2 of the substrate 110 .

[0043] In some embodiments, the stacked structure 120 and the separation channel 130 can be disposed on the same side of the substrate 110. For example, in one embodiment, the stacked structure 120 is disposed on the upper surface 110a of the substrate 110, and the separation channel 130 extends toward the lower surface 110b of the substrate 110, exposing the upper surface 110a of the substrate 110. The upper surface 110a includes a first upper surface 110a-1, a second upper surface 110a-2, and a third upper surface 110a-3. The first upper surface 110a-1, the second upper surface 110a-2, and the third upper surface 110a-3 can be substantially flat or rough. Referring to FIG. 1 and FIG. 6A , the separation channel 130 includes a first region 130-1, a second region 130-2, and a third region 130-3, with the second region 130-2 located between the first region 130-1 and the third region 130-3. Along the Y direction, the first region 130-1 is closest to the light-emitting end surface 100r or the reflective end surface 100s of the stacked structure 120, and the third region 130-3 is farthest from the light-emitting end surface 100r or the reflective end surface 100s of the stacked structure 120. Therefore, it can be seen that the first region 130-1 is closer to the light-emitting end surface 100r or the reflective end surface 100s of the stacked structure 120 than the second region 130-2, and the second region 130-2 is closer to the light-emitting end surface 100r or the reflective end surface 100s of the stacked structure 120 than the third region 130-3. The first region 130-1 exposes the first upper surface 110a-1 of the substrate 110, the second region 130-2 exposes the second upper surface 110a-2 of the substrate 110, and the third region 130-3 exposes the third upper surface 110a-3 of the substrate 110.

[0044] The first scribe trench 131 is closer to the ridge structure 122R than the separation trench 130. The first scribe trench 131 and the separation trench 130 may be in contact with each other, or they may completely or partially overlap. A first step H1 exists between the first scribe surface 110c exposed by the first scribe trench 131 and the first upper surface 110a-1, and they are not located on the same horizontal plane. The first step H1 has a depth that is substantially the same as the second depth D2 or the third depth D3. The first step H1 may be 0.1 micrometer to 10 micrometers, 2 micrometers to 8 micrometers, or 3 micrometers to 5 micrometers.

[0045] The second scribe line trench 170 is further away from the ridge structure 122R than the separation trench 130. The second scribe line trench 170 may be adjacent to, partially overlap, or completely overlap the separation trench 130. The second scribe line surface 110a-4 exposed by the second scribe line trench 170 has a step difference from the second upper surface 110a-2 and the third upper surface 110a-3, and is not located on the same horizontal plane as the second upper surface 110a-2 and the third upper surface 110a-3. In other words, the second scribe line surface 110a-4 is closer to the lower surface 110b of the substrate 110 than the second upper surface 110a-2 and the third upper surface 110a-3. The second upper surface 110a-2 and the third upper surface 110a-3 may be located on the same horizontal plane to form a continuous plane, or on different horizontal planes with a step difference. The second scribe line surface 110a-4 is closer to the lower surface 110b of the substrate 110 than the first scribe line surface 110c. A second step difference H2 between the second scribe surface 110a-4 and the top surface 122T is substantially equal to the first depth D1 between the first top surface 110a-1 and the top surface 122T. The second step difference H2 can be 12 μm to 35 μm, 18 μm to 30 μm, or 20 μm to 28 μm. The first scribe depth d1 and the second scribe depth d2 are substantially equal, and can be 8 μm to 31 μm, 14 μm to 26 μm, or 16 μm to 24 μm. In one embodiment of the present invention, because the first scribe surface 110c and / or the second scribe surface 110a-4 are formed by laser scribing, the first scribe surface 110c and / or the second scribe surface 110a-4 have a roughness greater than the roughness of the first top surface 110a-1, the second top surface 110a-2, and the third top surface 110a-3.

[0046] FIG6B shows a schematic diagram of separation trenches 130', first scribe trenches 131', and second scribe trenches 170' exposing the lower surface 110b of the substrate 110 according to one embodiment of the present invention. To make other features of the present invention clearer, some elements may be omitted in FIG6B.

[0047] The separation trench 130' and the ridge structure 122R are respectively located on the lower surface 110b and the upper surface 110a of the substrate 110. The separation trench 130' is connected to the first scribe trench 131' and extends from the lower surface 110b of the substrate 110 to the upper surface 110a of the substrate 110.

[0048] In some embodiments, the stacked structure 120 and the separation trench 130' can be disposed on opposite sides of the substrate 110. For example, in one embodiment, the stacked structure 120 is disposed on the upper surface 110a of the substrate 110, and the separation trench 130' extends from the lower surface 110b of the substrate 110 toward the upper surface 110a of the substrate 110, exposing the first upper surface 110a-1', the second upper surface 110a-2', and the third upper surface 110a-3' of the substrate 110. Referring to FIG. 6B , the separation trench 130' includes a first region 130-1, a second region 130-2, and a third region 130-3, respectively exposing different upper surfaces of the substrate 110, for example, the first upper surface 110a-1', the second upper surface 110a-2', and the third upper surface 110a-3'. The separation trench 130' may have different depths in different regions, such as a first depth D1' between the lower electrode 150 and the first upper surface 110a-1', a second depth D2' between the lower electrode 150 and the second upper surface 110a-2', and a third depth D3' between the lower electrode 150 and the third upper surface 110a-3'. In one embodiment, the first depth D1', the second depth D2', and the third depth D3' may be different from each other. For example, the first depth D1' may be greater than the second depth D2', and the second depth D2' may be approximately the same as or different from the third depth D3', but this is not limiting.

[0049] The first scribe trench 131' is adjacent to, fully or partially overlaps, and has a first scribe depth d1' to expose the first scribe surface 110c'. The second scribe trench 170' is adjacent to or overlaps the scribe trench 130' and has a second scribe depth d2' to expose the second scribe surface 110a-4'. The first scribe depth d1' and the second scribe depth d2' are substantially the same, and can be 8 to 31 microns, 14 to 26 microns, or 16 to 24 microns.

[0050] The separation trench 130' is closer to the third side s3 of the substrate 110 than the first scribe trench 131'. The first scribe trench 131' and the separation trench 130' may be connected, completely, or partially overlapped. A first step H1' exists between the first scribe surface 110c' exposed by the first scribe trench 131' and the first top surface 110a-1', and they are not located on the same horizontal plane. The first step H1' has a depth that is substantially the same as the second depth D2' or the third depth D3'. The first step H1' may be 0.1 micrometer to 10 micrometers, 2 micrometers to 8 micrometers, or 3 micrometers to 5 micrometers.

[0051] The second scribe trench 170' is closer to the third side s3 of the substrate 110 than the separation trench 130'. The second scribe trench 170' may be in contact with, partially overlap, or completely overlap the separation trench 130'. The second scribe surface 110a-4' exposed by the second scribe trench 170' has a step difference from the second upper surface 110a-2' and / or the third upper surface 110a-3', and is not located on the same horizontal plane as the second upper surface 110a-2' and the third upper surface 110a-3'. The second upper surface 110a-2' and the third upper surface 110a-3' may be located on the same horizontal plane to form a continuous plane, or on different horizontal planes with a step difference. The second scribe surface 110a-4' is closer to the upper surface 110a of the substrate 110 than the first scribe surface 110c'. A second step H2′ between the second scribe surface 110a-4′ and the lower electrode 150 is substantially the same as the first depth D1′ between the first upper surface 110a-1′ and the lower electrode 150. The second step H2′ may be 12 μm to 35 μm, 18 μm to 30 μm, or 20 μm to 28 μm.

[0052] FIG7 illustrates a top view of a semiconductor laser device rod 10 according to an embodiment of the present invention. FIG7 illustrates a semiconductor laser device rod 10 comprising a plurality of unseparated semiconductor laser devices 100 of FIG1 , and FIG7 corresponds to a plane defined by the X and Y directions. FIG8A illustrates a cross-sectional view taken along a line connecting the endpoints of section line CC' in FIG7 . FIG8B illustrates a cross-sectional view taken along a line connecting the endpoints of section line D-D' in FIG7 . FIG8C illustrates a cross-sectional view taken along a line connecting the endpoints of section line E-E' in FIG7 . FIG8A, FIG8B, and FIG8C illustrate a cross-sectional view taken along a line connecting the endpoints of section line E-E' in FIG7 , respectively. FIG8A, FIG8B, and FIG8C correspond to planes defined by the X and Z directions, respectively.

[0053] Referring simultaneously to Figures 7, 8A, 8B, and 8C, to separate the plurality of semiconductor laser devices 100 in the semiconductor laser device bar 10 into individual devices, separation trenches 130 and second scribe trenches 170 are provided on the substrate 110. In one embodiment, the separation trenches 130 are provided on the substrate 110 on one side of the ridge structure 122R along the X-direction. Alternatively, in one embodiment, multiple separation trenches 130 are provided on the substrate 110 on both sides of the ridge structure 122R along the X-direction, such that the ridge structure 122R is sandwiched between two adjacent separation trenches 130. Alternatively, the separation trenches 130 can be considered to be sandwiched between two adjacent ridge structures 122R. The separation trenches 130 expose the substantially flat first, second, and third upper surfaces 110a-1, 110a-2, and 110a-3 of the substrate 110. As shown in Figures 8A to 8D, by applying external stress along line L-L' on the second scribe trench 170, such as by blade breaking, roller breaking, or extrusion breaking, the semiconductor laser device rod 10 is divided into a plurality of semiconductor laser devices 100. It should be understood that the same or similar devices may have the same or similar materials, structures, or functions. Those skilled in the art may make equivalent modifications and variations without departing from the spirit of the present invention, and repeated details will not be repeated.

[0054] Please refer to Figures 7, 8A, 8B, and 8C simultaneously. The different sections C-C', D-D', and EE' in Figure 7 correspond to three adjacent regions of the separation trench 130. The C-C' section corresponds to the cross-sectional view of the first region 130-1 of the separation trench 130 shown in Figure 8A. The DD' section corresponds to the cross-sectional view of the second region 130-2 of the separation trench 130 shown in Figure 8B. The EE' section shown in Figure 8C corresponds to the cross-sectional view of the third region 130-3 of the separation trench 130. In other words, the separation trench 130 includes the first region 130-1, the second region 130-2, and the third region 130-3, which respectively expose the first upper surface 110a-1, the second upper surface 110a-2, and the third upper surface 110a-3 of the substrate 110. Furthermore, the separation trench 130 of the semiconductor laser device rod 10 includes a pre-separation trench width 130W" and a separation trench length 130L. In FIG8A , a first region 130-1 corresponding to the CC' section line has a first depth D1; in FIG8B , a second region 130-2 corresponding to the D-D' section line has a second depth D2; and in FIG8C , a third region 130-3 corresponding to the EE' section line has a third depth D3. The depth of each region, representing the depth of the separation trench 130 in each region, is measured as a vertical distance parallel to the Z direction from the top surface 122T of the ridge structure 122R, which is farthest from the substrate 110, to the top surface of the substrate 110.

[0055] Referring to FIG. 7 , FIG. 8C , and FIG. 8D , a second scribe trench 170 is disposed on the third region 130 - 3 of the separation trench 130 . The second scribe trench 170 includes a pre-set second scribe trench width 170W″, a second scribe trench length 170L, and a second scribe depth d2. In one embodiment, the second scribe trench 170 is disposed on the third region 130 - 3 of the substrate 110 on one side of the ridge structure 122R along the X-direction. Alternatively, multiple second scribe trenches 170 are disposed on the substrate 110 on both sides of the ridge structure 122R, such that the ridge structure 122R is sandwiched between two second scribe trenches 170. Alternatively, the second scribe trench 170 can be viewed as being sandwiched between two adjacent ridge structures 122R. The second scribe trench 170 extends deep into the substrate 110 and exposes the second scribe surface 110a-4. Specifically, the second scribe trench 170 is located within the separation trench 130, such that the separation trench 130 accommodates the second scribe trench 170. When viewed from above, the second scribe trench 170 extends from the separation trench 130 into the substrate 110, forming a trench-in-trench structure.

[0056] Referring to FIG. 7 , in some embodiments, the second scribe trench 170 may have a flat or rough bottom in the XY plane, such as the second scribe surface 110 a-4 illustrated in FIG. In some embodiments, the second scribe trench 170 includes a second scribe depth d2 located between the third upper surface 110 a-3 and the second scribe surface 110 a-4. The second scribe depth d2 may be different from or the same as the first scribe depth d1. In some embodiments, the first depth D1 is substantially equal to the total depth of the third depth D3 and the second scribe depth d2. In some embodiments, as shown in FIG. 8A , extending from the first scribe trench 131 having the first scribe trench depth d1 toward the substrate 110 by a first step H1 results in the first upper surface 110 a-1 having the first depth D1, i.e., D1 = H1 + d1.

[0057] In one embodiment, the width of the front second scribe line trench 170W" is smaller than the width of the front separation trench 130W". In one embodiment, the width of the front second scribe line trench 170W" may be 3 μm to 17 μm, 6 μm to 14 μm, or 8 μm to 12 μm. The width of the front separation trench 130W" may be 5 μm to 30 μm, 15 μm to 25 μm, or 17 μm to 23 μm.

[0058] Referring to FIG. 7 , the second scribing trench 170 includes a second scribing trench start point 170S located near the reflective end surface 100s and a second scribing trench end point 170E located away from the reflective end surface 100s or considered to be near the light-emitting end surface 100r. The second scribing trench start point 170S does not directly contact the reflective end surface 100s but maintains a distance therefrom. In one embodiment, the second scribing trench start point 170S has a start distance 170SD that is recessed relative to the reflective end surface 100s. The start distance 170SD is greater than 1 micron, 10 microns, 20 microns, or 30 microns, but less than 50 microns. Similarly, the second scribing trench end point 170E does not directly contact the reflective end surface 100r but maintains a distance therefrom. In another embodiment, the second scribing trench end point 170E has an end distance 170ED that is recessed relative to the reflective end surface 100r. The end distance 170ED is greater than 1 micron, 10 microns, 20 microns, or 30 microns, but less than 50 microns. In one embodiment, the start distance 170SD and the end distance 170ED can be the same, or the start distance 170SD can be smaller or larger than the end distance 170ED.

[0059] When viewed from above, the separation trench 130 has a separation trench start point 130S located near the reflective end surface 100s and a separation trench end point 130E located away from the reflective end surface 100s or near the light emitting end surface 100r. The separation trench start point 130S may be co-located with the first scribing trench 131 on the first side s1 of the substrate 110, and / or the separation trench end point 130E may be co-located with the first scribing trench 131 on the second side s2 of the substrate 110. In one embodiment, the separation trench start point 130S may be closer to the reflective end surface 100s than the second scribing trench start point 170S. In another embodiment, the separation trench end point 130E may be closer to the light emitting end surface 100r than the second scribing trench end point 170E.

[0060] Referring to FIG. 8C , in one variant embodiment, the second scribe trench 170 may have a wedge-like cross-sectional shape in the XZ plane. In some embodiments, when the semiconductor laser device is viewed from a side, such as from the XZ plane, the second scribe surface 110a-4 of the second scribe trench 170 may directly contact the third upper surface 110a-3 and may be non-perpendicular to the third upper surface 110a-3 of the substrate 110, but may be an inclined surface. A base angle θ of the wedge may be greater than 10 degrees, for example, 10 to 25 degrees. The base angle θ is the angle between two adjacent second scribe surfaces 110a-4. The second scribe depth d2 may extend from the third upper surface 110a-3 to the bottom point 170B of the second scribe trench 170 ( FIG. 8C ). The second scribe depth d2 may be 8 to 31 microns, 14 to 26 microns, or 16 to 24 microns.

[0061] Referring to FIG. 8D , in a modified embodiment, the second scribe trench 170 may have a trapezoidal cross-section in the XZ plane. In some embodiments, when viewed from a side, such as the XZ plane, the second scribe trench 170 includes a second scribe surface 110a-4 and a slope 170C, which connects to the third upper surface 110a-3 via the slope 170C. The second scribe surface 110a-4 may be the bottommost surface of the second scribe trench 170, and the bottommost surface is substantially parallel to the third upper surface 110a-3. The second scribe depth d2 may be measured from the third upper surface 110a-3 to the second scribe surface 110a-4, parallel to the Z direction.

[0062] Referring to FIG. 8A , substrate 110 further includes one or more cracks, such as cracks 111, 112, 113, and 114. In one embodiment, cracks 111, 112, 113, and 114 may be located on the reflective end surface 100s or the light-emitting end surface 100r (not shown). Cracks 111, 112, 113, and 114 extend from the first scribe trench 131 and / or the separation trench 130 toward the lower surface 110b of substrate 110, but are not limited thereto. One or more of these cracks may extend in a direction generally parallel to the Z-direction. In one embodiment, first scribe trench 131 includes a width 131W that may be 15 to 35 microns, 20 to 30 microns, or 22 to 28 microns. In one embodiment, the number of cracks extending from the first scribe trenches 131 is greater than the number of cracks extending from the separation trenches 130 .

[0063] Figures 9A through 9J illustrate a manufacturing process flow for a semiconductor laser device 100 according to an embodiment of the present invention. Figures 9A through 9G illustrate planes corresponding to the X and Y directions, while Figures 9H through 9J illustrate planes corresponding to the Y and Z directions. To clarify other features of the present invention, some components may be omitted from Figures 9A through 9J.

[0064] First, referring to FIG. 9A , a substrate 110 is provided. A pre-stacked structure 120' is formed on the upper surface 110a of the substrate 110. The pre-stacked structure 120' includes, in order from the upper surface 110a of the substrate 110 along the Z direction (not shown), a first semiconductor layer (not shown), an active layer (not shown), a second semiconductor layer (not shown), and a contact layer (not shown). The growth method of the pre-stacked structure 120' is not particularly limited and can be achieved using metal-organic vapor phase epitaxy (MOVPE), metal-organic chemical vapor phase epitaxy (MOCVD), hydride vapor phase epitaxy (HVPE), or molecular beam epitaxy (MBE).

[0065] Subsequently, referring to FIG. 9B , a portion of the second semiconductor layer (not shown) is removed by lithography combined with inductively coupled plasma (ICP) dry etching to define the ridge structure 122R shown in FIG. 1 through FIG. 4 and FIG. 7 . This forms a stacked structure 120 (shown in FIG. 2 through FIG. 5 ) sequentially including the first semiconductor layer 121, the active layer 123, and the second semiconductor layer 122 along the Z direction (not shown) from the substrate 110. Ridge structure 122R comprises a portion of the second semiconductor layer 122 and is formed along the stacking direction.

[0066] 9C , the stacked structure 120 is selectively removed by etching using a combination of lithography and dry or wet etching, thereby defining separation trenches 130 substantially parallel to the ridge structure 122R on both sides of the ridge structure 122R formed in the previous step. The process then continues with the completion of the processes required for other components (not shown), such as forming the upper electrode 140, lower electrode 150, and protective layer 160 shown in FIG. 3 .

[0067] Continuing with FIG9D , a laser (not shown) is used to create discontinuous lines perpendicular to the extension direction of the ridge structure 122R, for example, along the X-direction, on both sides of the ridge structure 122R, intersecting the separation trenches 130. This removes portions of the substrate (not shown) and the stacked structure (not shown), forming line scribe trenches 115, as indicated by dashed lines in FIG9D . Multiple line scribe trenches 115 are separated from one another. This step forms the first line scribe trenches 131 shown in FIG1-2 , the first line scribe trenches 131 shown in FIG6A-6B , and the first line scribe trenches 131 shown in FIG7 and FIG8A . To facilitate cleaving in subsequent processes, the length of the line scribe trenches 115 can be 40 to 100 microns, 50 to 90 microns, or 60 to 80 microns, although the present invention is not limited thereto.

[0068] Continuing with FIG. 9E , by applying external stress to the scribe grooves 115, such as by blade breaking, roller breaking, or extrusion, cracks are formed along the scribe grooves 115, thereby separating the substrate 110 and the stacked structure (not shown) thereon into a plurality of semiconductor laser rods 10. The high-reflectivity structure 100RS and low-reflectivity structure 100ES shown in FIG. 5 are formed on the reflective end face 100s and light-emitting end face 100r, respectively, to form an optical resonator. The semiconductor laser rods 10 are transferred and temporarily secured to a stage, for example, by being transferred and adhered to an adhesive film 106. The adhesive film 106 can be a polymer adhesive film having a melting point lower than that of the substrate 110. When sufficient external force is applied to the adhesive film 106, the adhesive film 106 undergoes plastic deformation but does not rupture. FIG9E shows that the semiconductor laser device bar 10 includes a plurality of semiconductor laser devices 100 .

[0069] Continuing with FIG. 9F , within the separation trenches 130 of the semiconductor laser device rod 10, a laser is used to continuously or discontinuously remove portions of the substrate 110 along the extension direction of the separation trenches 130 on both sides of the ridge structure 122R, thereby forming second scribing trenches 170. To facilitate cleaving in subsequent processes, the second scribing trenches 170 can be designed to have a second scribing depth d2 as shown in FIG. 4 , for example, 8 to 31 microns, 14 to 26 microns, or 16 to 24 microns, although the present invention is not limited thereto.

[0070] Continuing with FIG. 9G , after laser 107 forms a second scribing trench 170 away from the reflective end face 100s or the light-emitting end face 100r, the adhesive film 106 is stretched along the X-direction to cleave the semiconductor laser device rod 10 along the second scribing trench 170, separating previously adjacent semiconductor laser devices 100 from each other in the X-direction. Subsequently, after removing the adhesive film 106, a plurality of semiconductor laser devices 100 are obtained (see FIG. 1 ). As shown in FIG. 2 , each semiconductor laser device 100 includes a substrate 110, a stacked structure 120, a separation trench 130, and a second scribing trench 170.

[0071] Figures 9H through 9J illustrate cross-sectional views corresponding to Figure 9F illustrating the process of forming the second scribing trench 170 using a laser. Referring to Figures 7 and 9H through 9J, in this embodiment, when the second scribing trench 170 is formed in the separation trench 130 using the laser 107, the first region 130-1 shown in Figures 1 and 7 is avoided. Specifically, the second scribing trench start point 170S and the second scribing trench end point 170E are positioned away from the reflective end face 100s and the light emitting end face 100r of the semiconductor laser device 100, maintaining an appropriate distance from the reflective end face 100s and the light emitting end face 100r. As shown in FIG. 9I , the starting point 170S of the second scribed channel has a starting distance 170SD that is retracted relative to the reflective end surface 100s, and the ending point 170E of the second scribed channel has an ending distance 170ED that is retracted relative to the light-emitting end surface 100r, thereby forming the first region 130-1 in FIG. 1 closer to the reflective end surface 100s or the light-emitting end surface 100r of the optical resonator than the second region 130-2, and the second region 130-2 closer to the reflective end surface 100s or the light-emitting end surface 100r of the optical resonator than the third region 130-3.

[0072] Compared to conventional comparative examples in which the second scribing trench start point 170S or the second scribing trench end point 170E are not far from the reflective end surface 100s or the light-emitting end surface 100r, the second scribing trench start point 170S and / or the second scribing trench end point 170E of the second scribing trench 170 in the semiconductor laser device 100 of the present invention are separated from the reflective end surface 100s or the light-emitting end surface 100r in the Y direction, thereby avoiding direct contact with the reflective end surface 100s or the light-emitting end surface 100r, respectively. Therefore, when the laser 107 cuts the substrate 110 and further cuts downwards into the adhesive film 106, the risk of contamination of the reflective end surface 100s or the light-emitting end surface 100r by splashes (not shown) generated by the laser 107 on the adhesive film 106 located at the bottom of the substrate 110, which is used to secure the substrate 110, is reduced or avoided. Since no splashes are splashed onto the reflective end face 100s or the light-emitting end face 100r, the problem of the laser 107 cutting the film 106 and causing splashes to contaminate the reflective end face 100s or the light-emitting end face 100r, thereby affecting the light output of the optical resonator and causing a loss in the yield of the semiconductor laser device 100, can be solved.

[0073] Since the second scribing trench 170 is formed using laser 107, it can form a V-shaped or trapezoidal profile with no specific crystal plane, as shown in the side view of FIG8C , or a U-shaped or trapezoidal profile, as shown in the schematic diagrams of FIG6A / 6B . The width and depth of the second scribing trench 170 are determined by the laser's focused energy and frequency.

[0074] Because the semiconductor laser device of the present invention includes a second scribe trench that is appropriately recessed from the end facet, is disposed within the trench, and extends along the trench's extension direction, it reduces the problem of laser-generated spatter contaminating the light-emitting side of the semiconductor laser device. Compared to a comparative example without a second scribe trench appropriately distanced from the end facet, the semiconductor laser device of the present invention keeps laser-generated spatter as far away from the light-emitting side as possible, thereby resolving the yield loss problem of semiconductor laser devices caused by laser-generated spatter contaminating the light-emitting side and, in turn, affecting the light output of the optical resonator.

[0075] FIG10 illustrates a cross-sectional view of a laser diode device 2 according to an embodiment of the present invention. Referring to FIG10 , the laser diode device 2 includes a heat sink 21, first and second pins 22a and 22b, a mounting base 23, a submount 231, a laser diode chip 24, and a metal cover 27. The first and second pins 22a and 22b are disposed on the backside of the heat sink 21. The mounting base 23 protrudes from the surface of the heat sink 21 and is connected to the second pin 22b, which is grounded (GND). The submount 231 is disposed inside the mounting base 23 and provides a connection for the laser diode chip 24. The metal cover 27 further includes a glass window 271 disposed on its top surface. The bottom edge of the metal cover 27 is bonded to the top of the heat sink 21. The laser diode chip 24 may comprise a semiconductor laser device according to any embodiment of the present invention (e.g., semiconductor laser device 100), but the present invention is not limited thereto.

[0076] In summary, although the present invention has been disclosed above through the use of embodiments, this is not intended to limit the present invention. Persons skilled in the art will readily appreciate that various modifications and alterations may be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

[0077] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

[0078] 2: Laser diode device

[0079] 10: Semiconductor laser element rod

[0080] 21: Heat sink

[0081] 22a: First pin

[0082] 22b: Second pin

[0083] 23: Fixed seat

[0084] 231: Secondary fixed seat

[0085] 24: Laser diode chip

[0086] 27:Metal cover

[0087] 271: Glass Window

[0088] 100:Semiconductor laser device

[0089] 100L: Component length

[0090] 100W: Component width

[0091] 100H: Component height

[0092] 100ES: low reflectivity structure

[0093] 100RS: High reflectivity structure

[0094] 100r: light output end face

[0095] 100s: Reflective end face

[0096] 106: Film

[0097] 107: Laser

[0098] 110:Substrate

[0099] 110a: Upper surface

[0100] 110a-1: first upper surface

[0101] 110a-2: Second upper surface

[0102] 110a-3: third upper surface

[0103] 110a-4: Second scribing surface

[0104] 110b: lower surface

[0105] 110c: first scribed surface

[0106] 111: Crack

[0107] 112: Crack

[0108] 113: Crack

[0109] 114: Crack

[0110] 115: Scribe trench

[0111] 120: stacked structure

[0112] 120': Front stacking structure

[0113] 121: first semiconductor layer

[0114] 121L: First length

[0115] 121W: First width

[0116] 122: Second semiconductor layer

[0117] 122L: Second length

[0118] 122W: Second width

[0119] 122T: Top surface

[0120] 122R: Ridge structure

[0121] 123: Active layer

[0122] 124: conductive contact layer

[0123] 124d: Contact distance

[0124] 130: Separation channel

[0125] 130C: Separation trench edge

[0126] 130B: separation trench bottom

[0127] 130W: Separation channel width

[0128] 130W”: Pre-separation channel width

[0129] 130D: Separation trench depth

[0130] 130S: Starting point of separation channel

[0131] 130E: Separation channel end point

[0132] 130-1: Area 1

[0133] 130-2: Second Area

[0134] 130-3: Third Area

[0135] 131: first scribe channel

[0136] 140: Upper electrode

[0137] 140d: Distance

[0138] 150: lower electrode

[0139] 160: Protective layer

[0140] 170: Second scribing channel

[0141] 170C: Second line bevel

[0142] 170W: Second scribe channel width

[0143] 170W”: Front second scribe line channel width

[0144] 170L: Second scribe channel length

[0145] 170S: Starting point of the second scribe trench

[0146] 170E: End point of the second scribe channel

[0147] 170B: bottom point

[0148] 170ED: End distance

[0149] 170SD: Starting distance

[0150] D1: First depth

[0151] D2: Second Depth

[0152] D3: Third Depth

[0153] d1: first stroke depth

[0154] d2: second stroke depth

[0155] H1: First order difference

[0156] H2: Second order difference

[0157] RH: Ridge Height

[0158] RW: Ridge Width

[0159] RL: Ridge length

[0160] s1: first side

[0161] s2: second side

[0162] s3: third side

[0163] s4: fourth side

[0164] none.

Claims

1. A semiconductor laser element, comprising: a substrate having a first side and a second side opposite to each other, a first scriber surface, and a first upper surface; a stacked structure located on the substrate and having a top surface, and including a first semiconductor layer, an active layer, and a second semiconductor layer along a stacking direction, the second semiconductor layer having a ridge structure; a first scriber channel formed in the stacked structure and extending from the top surface of the stacked structure toward the substrate to the first scriber surface of the substrate, the first scriber channel not extending to the first side and the second side; and a separation channel located on one side of the ridge structure and formed in the stacked structure, extending from the first side to the second side; The separation channel includes a first region extending from the top surface of the stacked structure to the first upper surface of the substrate. The distance between the top surface of the stacked structure and the first upper surface of the substrate is defined as a first depth. The first region is connected to or overlaps with the first scribing channel. The distance between the first upper surface and the first scribing surface of the substrate is defined as a first scribing depth. The first scribing depth is greater than the first depth.

2. A semiconductor laser element, comprising: a substrate having an upper surface, a lower surface, a first side and a second side, a first scribe channel, and a first upper surface; a stacked structure located on the substrate and having a top surface, and including a first semiconductor layer, an active layer, and a second semiconductor layer along a stacking direction, the second semiconductor layer having a ridge structure; a first scribe channel formed in the substrate and extending from the lower surface of the substrate toward the stacked structure to a first scribe surface of the substrate, the first scribe channel not extending to the first side and the second side; and a separation channel formed in the substrate and extending from the first side to the second side; the separation channel including a first region extending from the lower surface of the substrate toward the stacked structure to the first upper surface, the distance between the first upper surface of the substrate and the lower surface of the substrate being defined as a first depth; wherein, The first region is connected to or overlaps with the first scribing groove, and the distance between the first upper surface and the first scribing surface of the substrate is defined as a first scribing depth, which is greater than the first depth.

3. The semiconductor laser element of claim 1, wherein the substrate further has a second scribe surface, the semiconductor laser further includes a second scribe channel formed in the stacked structure and extending from the top surface of the stacked structure toward the substrate to the second scribe surface of the substrate, and in a top view, the second scribe channel is located on the first side or the second side of the substrate.

4. The semiconductor laser element of claim 3, wherein the second scribe channel includes a second scribe depth defined as the distance between the top surface of the stacked structure and the second scribe surface, the substrate further has a second upper surface, the separation channel further includes a second region extending from the top surface of the stacked structure toward the substrate to the second upper surface, the distance between the top surface of the stacked structure and the second upper surface of the substrate is defined as a second depth, and the second scribe depth is less than the second depth.

5. The semiconductor laser element of claim 2, wherein the substrate further has a second scribe surface, and the semiconductor laser further includes a second scribe channel formed in the substrate and extending from the lower surface of the substrate toward the stacked structure to the second scribe surface of the substrate, wherein, in a top view, the second scribe channel is located on the first side or the second side of the substrate.

6. The semiconductor laser element of claim 5, wherein the second scribe channel includes a second scribe depth defined at the distance between the lower surface of the substrate and the second scribe surface, the substrate further has a second upper surface, the scribe channel further includes a second region extending from the lower surface of the substrate toward the second upper surface, the distance between the lower surface of the substrate and the second upper surface of the substrate is defined as a second depth, and the second scribe depth is less than the second depth.

7. The semiconductor laser element as claimed in claim 6, wherein the second scribe depth is substantially the same as the first scribe depth.

8. The semiconductor laser element as claimed in claim 1 or 2, wherein the first scribe channel includes a length less than the length of one of the scribe channels.

9. The semiconductor laser element as claimed in claim 1, wherein, The substrate also has a third upper surface, and the separation channel further includes a third region extending from the top surface of the stacked structure toward the substrate to the third upper surface. The third region is located between the first region and the second scribing channel. The distance between the top surface of the stacked structure and the third upper surface of the substrate is defined as a third depth, and the first depth is approximately the same as the third depth.

10. The semiconductor laser element as claimed in claim 2, wherein, The substrate also has a third upper surface, and the separation channel further includes a third region extending from the lower surface of the substrate toward the stacked structure to the third upper surface. The third region is located between the first region and the second scribing channel. The distance between the lower surface of the substrate and the third upper surface of the substrate is defined as a third depth, and the first depth is approximately the same as the third depth.

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