Optical pumping semiconductor laser and preparation method thereof

Abstract

The invention provides an optical pumping semiconductor laser and a preparation method thereof. The optical pumping semiconductor laser comprises a semiconductor gain chip, a first heat sink and a second heat sink, the semiconductor gain chip comprises an active layer, a first light-transmitting heat dissipation structure, a second light-transmitting heat dissipation structure, a first film system and a second film system. The first light-transmitting heat dissipation structure and the second light-transmitting heat dissipation structure are located on the two sides of the active layer in the first direction respectively. The first film system is located on the surface of the side, away from the active layer, of part of the first light-transmitting heat dissipation structure. The second film system is located on the surface of the side, away from the active layer, of part of the second light-transmitting heat dissipation structure. Wherein the first heat sink is located on the side, away from the active layer, of part of the first light-transmitting heat dissipation structure, and the first heat sink is located on the side, in the second direction, of the first film system; the second heat sink is located on the side, away from the active layer, of part of the second light-transmitting heat dissipation structure, and the second heat sink is located on the side, in the second direction, of the second film system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor, in particular to a kind of optically pumped semiconductor laser and preparation method thereof. BACKGROUND

[0002] Optically pumped semiconductor light emitting device is with certain semiconductor material as working substance and produces stimulated emission effect, its working principle is: through certain optical pumping excitation mode, between the energy band (conduction band and valence band) of semiconductor material, or between the energy band of semiconductor material and impurity (acceptor or donor) energy level, realize the particle number inversion of non-equilibrium carrier, when a large number of electrons and holes in particle number inversion state are combined, stimulated emission effect is generated, because semiconductor light emitting device is small in size, high optical conversion efficiency is widely used.

[0003] Optically pumped external cavity surface emitting semiconductor laser is an important optically pumped semiconductor laser, it overcomes the limitation of mode area of traditional electrically pumped semiconductor laser by combining semiconductor gain medium and optical resonator, can realize high output power and high beam quality single mode output, is a new type of solution to realize high brightness laser. SUMMARY

[0004] The technical problem to be solved by the present application is how to enhance the power of optically pumped semiconductor laser and increase the spectral tuning range, so as to provide an optically pumped semiconductor laser and a preparation method thereof.

[0005] The present application provides an optically pumped semiconductor laser, comprising a semiconductor gain chip, a first heat sink and a second heat sink; wherein the semiconductor gain chip comprises: an active layer, a first light-transmitting heat dissipation structure, a second light-transmitting heat dissipation structure, a first film system and a second film system; the first light-transmitting heat dissipation structure is located on one side of the active layer along a first direction; the second light-transmitting heat dissipation structure is located on the other side of the active layer along the first direction; the first film system is located on the surface of part of the first light-transmitting heat dissipation structure away from the active layer; the second film system is located on the surface of part of the second light-transmitting heat dissipation structure away from the active layer; wherein the first heat sink is located on the side of part of the first light-transmitting heat dissipation structure away from the active layer, and the first heat sink is located on the side of the first film system along a second direction; the second heat sink is located on the side of part of the second light-transmitting heat dissipation structure away from the active layer, and the second heat sink is located on the side of the second film system along the second direction; wherein the first direction and the second direction are perpendicular.

[0006] Optionally, the thickness of the first light-transmitting heat dissipation structure in the first direction is greater than the thickness of the first film system in the first direction, and the thickness of the second light-transmitting heat dissipation structure in the first direction is greater than the thickness of the second film system in the first direction.

[0007] Optionally, the first light-transmissive heat-dissipation structure has a thickness of 500 nm to 10 mm in the first direction; and the second light-transmissive heat-dissipation structure has a thickness of 500 nm to 10 mm in the first direction.

[0008] Optionally, the material of the first light-transmissive heat-dissipation structure comprises any one of diamond, silicon carbide, sapphire and graphene; and the material of the second light-transmissive heat-dissipation structure comprises any one of diamond, silicon carbide, sapphire and graphene.

[0009] Optionally, the thermal conductivity of the first light-transmissive heat-dissipation structure is greater than the thermal conductivity of the first film system; and the thermal conductivity of the second light-transmissive heat-dissipation structure is greater than the thermal conductivity of the second film system.

[0010] Optionally, the absorption rate of the first light-transmissive heat-dissipation structure in the gain wavelength range of the active layer is less than or equal to 20%; and the absorption rate of the second light-transmissive heat-dissipation structure in the gain wavelength range of the active layer is less than or equal to 20%.

[0011] Optionally, the semiconductor gain chip further comprises: a first bonding layer between the first heat sink and the first light-transmissive heat-dissipation structure; and a second bonding layer between the second heat sink and the second light-transmissive heat-dissipation structure.

[0012] Optionally, the semiconductor gain chip further comprises: a first semiconductor barrier layer between the active layer and the second light-transmissive heat-dissipation structure; and a second semiconductor barrier layer between the active layer and the first light-transmissive heat-dissipation structure.

[0013] Optionally, the first semiconductor barrier layer has a thickness of 10 nm to 20 μm in the first direction; and the second semiconductor barrier layer has a thickness of 10 nm to 20 μm in the first direction.

[0014] Optionally, the first film system is a first anti-reflection film system, and the second film system is a second anti-reflection film system; the optical-pumping semiconductor laser further comprises a mirror and an output mirror; the mirror is located on the side of the second film system and the second heat sink away from the active layer and is spaced apart from the semiconductor gain chip and the second heat sink; the output mirror is located on the side of the first film system and the first heat sink away from the active layer and is spaced apart from the semiconductor gain chip and the first heat sink; and the mirror and the output mirror constitute a resonant cavity.

[0015] Optionally, the first film system is a first Bragg mirror, the second film system is a second Bragg mirror, the reflectivity of the second Bragg mirror is greater than the reflectivity of the first Bragg mirror, and the second film system and the first film system constitute a resonant cavity.

[0016] Optionally, the first film system is an anti-reflection film system, and the second film system is a reflection film system; the optically pumped semiconductor laser further comprises an output mirror located on a side of the first film system and the first heat sink away from the active layer and spaced apart from the semiconductor gain chip and the first heat sink; and a resonant cavity is formed between the second film system and the output mirror.

[0017] The application further provides a method for manufacturing an optically pumped semiconductor laser, comprising forming a semiconductor gain chip; forming the semiconductor gain chip comprises: forming an active layer on a side of a substrate along a first direction; disposing a first light-transmitting heat-dissipating structure on a side of the active layer away from the substrate, and then removing the substrate; after removing the substrate, disposing a second light-transmitting heat-dissipating structure on a side of the active layer away from the first light-transmitting heat-dissipating structure; forming a first film system on a surface of a part of the first light-transmitting heat-dissipating structure away from the active layer; and forming a second film system on a surface of a part of the second light-transmitting heat-dissipating structure away from the active layer; the method further comprises: bonding a first heat sink on a side of a part of the first light-transmitting heat-dissipating structure away from the active layer, the first heat sink being located on a side of the first film system along a second direction; and bonding a second heat sink on a side of a part of the second light-transmitting heat-dissipating structure away from the active layer, the second heat sink being located on a side of the second film system along the second direction; wherein the first direction is perpendicular to the second direction.

[0018] Optionally, forming the semiconductor gain chip further comprises: forming a first semiconductor barrier layer on a side of the substrate along the first direction; wherein forming the active layer comprises: forming the active layer on a side of the first semiconductor barrier layer away from the substrate; wherein removing the substrate comprises: removing the substrate with the first semiconductor barrier layer as an etching stop layer; and wherein disposing the second light-transmitting heat-dissipating structure on a side of the active layer away from the first light-transmitting heat-dissipating structure comprises: disposing the second light-transmitting heat-dissipating structure on a surface of the first semiconductor barrier layer away from the active layer.

[0019] Optionally, forming the semiconductor gain chip further comprises: forming a second semiconductor barrier layer on a side of the active layer away from the first semiconductor barrier layer; and wherein disposing the first light-transmitting heat-dissipating structure on a side of the active layer away from the substrate comprises: disposing the first light-transmitting heat-dissipating structure on a surface of the second semiconductor barrier layer away from the active layer.

[0020] Optionally, forming the semiconductor gain chip further comprises: forming a first bonding layer on a side surface of the part of the first light-transmitting heat-dissipating structure away from the active layer; and forming a second bonding layer on a side surface of the part of the second light-transmitting heat-dissipating structure away from the active layer; wherein the first bonding layer surrounds a sidewall of the first membrane system after the first membrane system is formed; and the second bonding layer surrounds a sidewall of the second membrane system after the second membrane system is formed; wherein bonding the first heat sink to the side of the part of the first light-transmitting heat-dissipating structure away from the active layer comprises: bonding the first heat sink to a side surface of the first bonding layer away from the first light-transmitting heat-dissipating structure; and wherein bonding the second heat sink to the side of the part of the second light-transmitting heat-dissipating structure away from the active layer comprises: bonding the second heat sink to a side surface of the second bonding layer away from the second light-transmitting heat-dissipating structure.

[0021] Optionally, the first membrane system is a first anti-reflection membrane system, and the second membrane system is a second anti-reflection membrane system; wherein the method for manufacturing the optically pumped semiconductor laser further comprises: disposing a mirror on a side of the second membrane system and the second heat sink away from the active layer and spaced apart from the semiconductor gain chip and the second heat sink; and disposing an output mirror on a side of the first membrane system and the first heat sink away from the active layer and spaced apart from the semiconductor gain chip and the first heat sink; and the mirror and the output mirror constitute a resonant cavity.

[0022] Optionally, the first membrane system is a first Bragg mirror, and the second membrane system is a second Bragg mirror; the reflectivity of the second Bragg mirror is greater than the reflectivity of the first Bragg mirror; and the second membrane system and the first membrane system constitute a resonant cavity.

[0023] Optionally, the first membrane system is an anti-reflection membrane system, and the second membrane system is a reflection membrane system; wherein the method for manufacturing the optically pumped semiconductor laser further comprises: disposing an output mirror on a side of the first membrane system and the first heat sink away from the active layer and spaced apart from the semiconductor gain chip and the first heat sink; and the second membrane system and the output mirror constitute a resonant cavity.

[0024] The technical scheme has the following beneficial effects: The light-pumped semiconductor laser provided by the technical scheme has the first light-transmitting heat-dissipating structure and the second light-transmitting heat-dissipating structure arranged on the two sides of the active layer along the first direction, the interval between the first film system and the second film system in the first direction is increased, the longitudinal mode interval is reduced, that is, the wavelength difference between adjacent longitudinal modes is reduced. The Fabry-Perot interference filtering effect between the first film system and the second film system is inhibited, the spectral modulation and filtering effect of the effect of the first film system and the second film system on the gain of the active layer are reduced, more longitudinal modes are allowed to output in the gain wavelength range of the active layer, the gain spectrum tuning range is increased, and wide-range wavelength tuning is facilitated. In addition, the waste heat of the active layer is directly transmitted to the first heat sink through the first light-transmitting heat-dissipating structure, and the waste heat of the active layer is directly transmitted to the second heat sink through the second light-transmitting heat-dissipating structure. The thermal conductivity of the first light-transmitting heat-dissipating structure and the second light-transmitting heat-dissipating structure is high, and the double-sided heat dissipation mode is adopted, so that the heat dissipation area is larger, and the heat dissipation capacity of the active layer is enhanced, the heat extraction of the active layer is facilitated, and the output power of the light-pumped semiconductor laser is improved.

[0025] In addition, the waste heat of the active layer can be transmitted without the first film system and the second film system, so that the size of the first film system in the first direction and the size of the second film system in the first direction are reduced, the size of the first film system in the first direction can be selected according to the design requirement, and the size of the second film system in the first direction can be selected according to the design requirement. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical scheme in the specific embodiments or prior art, the drawings needed in the following specific embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0027] Figure 1 FIG. 1 is a schematic diagram of a light-pumped semiconductor laser according to an embodiment of the present application; Figure 2 FIG. 2 is a schematic diagram of a light-pumped semiconductor laser according to another embodiment of the present application; Figure 3 FIG. 3 is a schematic diagram of a light-pumped semiconductor laser according to another embodiment of the present application; Figure 2 FIG. 4 is a schematic diagram of the reflectivity and wavelength variation of the first film system in FIG. 3; Figure 4 FIG. 5 is a schematic diagram of a light-pumped semiconductor laser according to another embodiment of the present application; Figure 5 FIG. 6 is a schematic diagram of the reflectivity and wavelength variation of the second film system in FIG. 5; Figure 4 Figure 6 FIG. 7 is a schematic diagram of the reflectivity and wavelength variation of the second film system in FIG. 6; ​Figure 6 A schematic view of a light pumped semiconductor laser according to yet another embodiment of the present application; Figure 7 A schematic view after forming a first semiconductor barrier layer, an active layer and a second semiconductor barrier layer on one side of the substrate along the first direction; Figure 8 A schematic view after disposing a first light-transmissive heat dissipation structure on a side of the active layer facing away from the substrate; Figure 9 A schematic view after removing the substrate on the basis of Figure 8 ; Figure 10 A schematic view after disposing a second light-transmissive heat dissipation structure on a side of the active layer facing away from the first light-transmissive heat dissipation structure; Figure 11 A schematic view after forming a first bonding layer and a second bonding layer on the basis of Figure 10 ; Figure 12 A bottom view of Figure 11 ; Figure 13 A top view of Figure 11 ; Figure 14 A schematic view after forming a first membrane system and a second membrane system on the basis of Figure 11 ; Figure 15 A schematic view after bonding a first heat sink on a side of part of the first light-transmissive heat dissipation structure facing away from the active layer and bonding a second heat sink on a side of part of the second light-transmissive heat dissipation structure facing away from the active layer. DETAILED DESCRIPTION

[0028] The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0029] In the description of the present application, it should be noted that the terms “center”, “upper”, “lower”, “left”, “right”, “vertical”, “horizontal”, “inner”, “outer” and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms “first”, “second”, “third” are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0030] In addition, the technical features involved in the different embodiments of the application described below can be combined with each other as long as there is no conflict.

[0031] Figure 1 A schematic diagram of an optically pumped semiconductor laser according to an embodiment of the application, Figure 2 A schematic diagram of an optically pumped semiconductor laser according to another embodiment of the application, Figure 4 A schematic diagram of an optically pumped semiconductor laser according to yet another embodiment of the application, Figure 6 A schematic diagram of an optically pumped semiconductor laser according to still another embodiment of the application. Reference is made to Figure 1 、 Figure 2 、 Figure 4 and Figure 6 The optically pumped semiconductor laser comprises a semiconductor gain chip W, a first heat sink 100 and a second heat sink 190. The semiconductor gain chip comprises an active layer 150, a first light-transmitting heat-dissipating structure 130, a second light-transmitting heat-dissipating structure 170, a first film system 120 and a second film system 200.

[0032] The first light-transmitting heat-dissipating structure 130 is located on one side of the active layer 150 along a first direction Z; the second light-transmitting heat-dissipating structure 170 is located on the other side of the active layer 150 along the first direction Z. The first film system 120 is located on a side surface of part of the first light-transmitting heat-dissipating structure 130 away from the active layer 150; the second film system 200 is located on a side surface of part of the second light-transmitting heat-dissipating structure 170 away from the active layer 150.

[0033] The first heat sink 100 is located on a side of part of the first light-transmitting heat-dissipating structure 130 away from the active layer 150, and the first heat sink 100 is located on a side of the first film system 120 along a second direction X; the second heat sink 190 is located on a side of part of the second light-transmitting heat-dissipating structure 170 away from the active layer 150, and the second heat sink 190 is located on a side of the second film system 200 along the second direction X.

[0034] The first direction Z and the second direction X are perpendicular.

[0035] The light-pumped semiconductor laser of the embodiment has the first light-transmitting heat-dissipating structure 130 and the second light-transmitting heat-dissipating structure 170 arranged respectively on the two sides of the active layer 150 along the first direction Z, the distance between the first film system 120 and the second film system 200 in the first direction Z is increased, the longitudinal mode distance is reduced, that is, the wavelength difference between adjacent longitudinal modes is reduced. The Fabry-Perot interference filtering effect between the first film system 120 and the second film system 200 is suppressed, the spectral modulation and filtering effect of the gain of the active layer 150 caused by the effect between the first film system 120 and the second film system 200 is suppressed, more longitudinal modes are allowed to output in the gain wavelength range of the active layer 150, and the gain spectrum tuning range is increased, which is beneficial to realize wide-range wavelength tuning; secondly, the waste heat of the active layer 150 is directly transmitted to the first heat sink 100 through the first light-transmitting heat-dissipating structure 130, and the waste heat of the active layer 150 is directly transmitted to the second heat sink 190 through the second light-transmitting heat-dissipating structure 170, the thermal conductivity of the first light-transmitting heat-dissipating structure 130 and the second light-transmitting heat-dissipating structure 170 is high, and the double-sided heat dissipation mode is adopted, so the heat dissipation area is larger, and therefore the heat dissipation capability of the active layer 150 is enhanced, which is beneficial to the heat extraction of the active layer 150 and improves the output power of the light-pumped semiconductor laser.

[0036] In addition, the waste heat of the active layer 150 can be transmitted without the first film system 120 and the second film system 200, so the size of the first film system 120 in the first direction Z and the size of the second film system 200 in the first direction Z are reduced, the size of the first film system 120 in the first direction Z can be selected according to the design requirement, and the size of the second film system 200 in the first direction Z can be selected according to the design requirement.

[0037] In one embodiment, referring to Figure 2, the first film system 120 is a first anti-reflection film system, specifically, the first film system 120 is a first anti-reflection film system for the output wavelength of the optically pumped semiconductor laser, and the second film system 200 is a second anti-reflection film system, the second film system 200 is a second anti-reflection film system for the output wavelength of the optically pumped semiconductor laser; wherein the optically pumped semiconductor laser further comprises: a mirror 301 and an output mirror 400; the mirror 301 is located on the side of the second film system 200 and the second heat sink 190 away from the active layer 150 and is spaced apart from the semiconductor gain chip W and the second heat sink 190; the output mirror 400 is located on the side of the first film system 120 and the first heat sink 100 away from the active layer 150 and is spaced apart from the semiconductor gain chip W and the first heat sink 100; the mirror 301 and the output mirror 400 form a resonant cavity therebetween. Wherein the mirror 301 and the output mirror 400 are located on both sides of the semiconductor gain chip W in the first direction Z. The reflectivity of the mirror 301 is greater than the reflectivity of the output mirror 400, and the laser is emitted from the output mirror 400. In this case, the optically pumped semiconductor laser is an optically pumped external cavity surface emitting semiconductor laser.

[0038] When the first film system 120 is a first anti-reflection film system and the second film system 200 is a second anti-reflection film system, the reflectivity of the first film system 120 to the active layer 150 gain wavelength and the reflectivity of the second film system 200 to the active layer 150 gain wavelength are both small, which further suppresses the Fabry-Perot interference filtering effect and parasitic oscillation of the composite microcavity between the first film system 120 and the second film system 200, which further increases the gain spectrum tuning range, and further realizes wide-range wavelength tuning.

[0039] In one embodiment, when the first film system 120 is a first anti-reflection film system and the second film system 200 is a second anti-reflection film system, the reflectivity of the first film system 120 at the center wavelength of the light emitted by the optically pumped semiconductor laser is less than or equal to 0.2%, and the reflectivity of the second film system 200 at the center wavelength of the light emitted by the optically pumped semiconductor laser is less than or equal to 0.2%.

[0040] Reference Figure 3 , Figure 3 is Figure 2 a schematic diagram of the variation of the reflectivity of the first film system 120 with wavelength in the first film system 120, also representing the variation of the reflectivity of the second film system 200 with wavelength; the reflectivity of the first film system 120 to light of 980 nm wavelength is less than or equal to 0.2%, and the reflectivity of the second film system 200 to light of 980 nm wavelength is less than or equal to 0.2%.

[0041] When the first film system 120 is a first anti-reflection film system and the second film system 200 is a second anti-reflection film system, the thickness of the first film system 120 in the first direction Z can be made smaller, and the thickness of the second film system 200 in the first direction Z can be made smaller, for example, the thickness of the first film system 120 in the first direction Z is 150 nm to 600 nm, for example, 150 nm, 200 nm, 300 nm, 400 nm, 500 nm or 600 nm; the thickness of the second film system 200 in the first direction Z is 150 nm to 600 nm, for example, 150 nm, 200 nm, 300 nm, 400 nm, 500 nm or 600 nm.

[0042] Figure 2 The semiconductor gain chip W in the semiconductor laser device 100 is optically pumped by the pump light 500 in a way of oblique incidence, the mirror 301 has a high reflectivity (for example, the reflectivity is greater than 90%) to the laser light emitted by the semiconductor gain chip W, and the output mirror 400 has a partial transmission characteristic (for example, the transmission rate is 0.5% to 10%) to the laser light emitted by the semiconductor gain chip W. A resonant cavity is formed between the output mirror 400 and the mirror 301, and the laser light is amplified by stimulated emission in the resonant cavity and then output through the output mirror 400.

[0043] It should be noted that in the prior art, when the optical pump external cavity surface emitting semiconductor laser is prepared, a bottom Bragg reflector and an active layer are sequentially grown on a substrate, and the material of the bottom Bragg reflector is a semiconductor material. When the active layer is grown, the material of the active layer needs to be lattice matched with the material of the semiconductor Bragg reflector, otherwise the active layer cannot emit light or has poor performance, thus having complex process requirements. Secondly, in the prior art, the semiconductor-air interface at the top of the epitaxial wafer of the optical pump external cavity surface emitting semiconductor laser and the bottom Bragg reflector form a Fabry-Perot microcavity, which introduces a Fabry-Perot interference filtering effect. This effect causes spectral modulation and filtering of the intrinsic material gain of the active layer, which narrows the gain spectrum and makes it difficult to achieve wide-range wavelength tuning. Moreover, when the optical pump external cavity surface emitting semiconductor laser is working, the active layer generates a large amount of waste heat. Since the active layer is above the bottom Bragg reflector, a relatively thick bottom Bragg reflector increases the length of the heat dissipation channel, which is not conducive to heat extraction and power improvement of the active layer. In contrast, the optical pump external cavity surface emitting semiconductor laser of the present application can improve the above problems.

[0044] The optical pump external cavity surface emitting semiconductor laser of the present application can be applied to the fields of laser display, laser medical treatment, laser detection, etc.

[0045] The output wavelength of the optically pumped external cavity surface emitting semiconductor laser of the present application has a wavelength tuning freedom of tens of nanometers or even hundreds of nanometers. For example, the wavelength tuning range of the output wavelength of the optically pumped external cavity surface emitting semiconductor laser is 20nm~40nm.

[0046] In another embodiment, referring to Figure 6 , the first film system 120 is a first Bragg reflector, the second film system 200 is a second Bragg reflector, the reflectivity of the second Bragg reflector is greater than the reflectivity of the first Bragg reflector, and a resonant cavity is formed between the second film system 200 and the first film system 120. Due to the first light-transmitting heat-dissipating structure 130 and the second light-transmitting heat-dissipating structure 170, the distance between the first film system 120 and the second film system 200 in the first direction Z is increased, the Fabry-Perot interference filtering effect between the first film system 120 and the second film system 200 is suppressed, the spectral modulation and filtering effect of the gain of the active layer 150 caused by the effect is suppressed, and the gain spectrum tuning range is increased, thereby realizing wide-range wavelength tuning. Laser light is emitted from the first film system 120.

[0047] In another embodiment, referring to Figure 4 , the first film system 120 is an antireflection film system, and the second film system 200 is a reflective film system; wherein the optically pumped semiconductor laser further comprises an output mirror 400, the output mirror 400 is located on the side of the first film system 120 and the first heat sink 100 away from the active layer 150 and is spaced apart from the semiconductor gain chip W and the first heat sink 100; and a resonant cavity is formed between the second film system 200 and the output mirror 400. The reflectivity of the second film system 200 is greater than the reflectivity of the output mirror 400. Laser light is emitted from the output mirror 400.

[0048] In one embodiment, when the first film system 120 is a first antireflection film system, the reflectivity of the first film system 120 at the central wavelength of the light emitted by the optically pumped semiconductor laser is less than or equal to 0.2%.

[0049] When the first film system 120 is a first antireflection film system, the thickness of the first film system 120 in the first direction Z can be made smaller, for example, the thickness of the first film system 120 in the first direction Z is 150nm~600nm, for example, 150nm, 200nm, 300nm, 400nm, 500nm or 600nm.

[0050] Referring to Figure 5 , Figure 5 is Figure 4 and Figure 6Figure 2 shows a schematic diagram of the reflectivity of the second film system 200 as a function of wavelength; the second film system 200 has a high reflectivity (e.g. reflectivity > 90%) for the laser light (980 nm wavelength light) emitted by the semiconductor gain chip W, for example a reflectivity of 99%.

[0051] Referring to Figure 4 , the first film system 120 has a partial transmission characteristic (e.g. transmission of 0.5% to 10%) for the laser light (980 nm wavelength light) emitted by the semiconductor gain chip W. The first film system 120 and the output mirror 400 form a resonant cavity, and the laser light is amplified by stimulated emission in the resonant cavity and then output through the output mirror 400.

[0052] Referring to Figure 6 , the first film system 120 has a partial transmission characteristic (e.g. transmission of 0.5% to 10%) for the laser light (980 nm wavelength light) emitted by the semiconductor gain chip W. The first film system 120 and the second film system 200 form a resonant cavity, and the laser light is amplified by stimulated emission in the resonant cavity and then output through the first film system 120.

[0053] In one embodiment, referring to Figure 1 , Figure 2 , Figure 4 and Figure 6 , the first light-transmitting heat-dissipating structure 130 has a thickness in the first direction Z that is greater than the thickness of the first film system 120 in the first direction Z, and the second light-transmitting heat-dissipating structure 170 has a thickness in the first direction Z that is greater than the thickness of the second film system 200 in the first direction Z. That is, the first light-transmitting heat-dissipating structure 130 has a greater thickness in the first direction Z, and the second light-transmitting heat-dissipating structure 170 has a greater thickness in the first direction Z, further increasing the spacing between the first film system 120 and the second film system 200, further reducing the spectral modulation and filtering effect of the active layer 150 by the effect between the first film system 120 and the second film system 200, further increasing the gain spectral tuning range, and further achieving wide-range wavelength tuning.

[0054] In one embodiment, the first light-transmitting heat-dissipating structure 130 has a thickness in the first direction Z of 500 nm to 10 mm, for example 0.8 mm to 1 mm; and the second light-transmitting heat-dissipating structure 170 has a thickness in the first direction Z of 500 nm to 10 mm, for example 0.8 mm to 1 mm.

[0055] In an embodiment, the thermal conductivity of the first light-transmissive heat dissipation structure 130 is greater than the thermal conductivity of the first film system 120, and the thermal conductivity of the second light-transmissive heat dissipation structure 170 is greater than the thermal conductivity of the second film system 200. The thermal conductivity of the first light-transmissive heat dissipation structure 130 is higher, and the thermal conductivity of the second light-transmissive heat dissipation structure 170 is higher, so that the waste heat of the active layer 150 is dissipated through the second light-transmissive heat dissipation structure 170 and the first light-transmissive heat dissipation structure 130, which is conducive to the heat dissipation of the active layer 150; and the first film system 120 and the second film system 200 can be free from heat dissipation, and the size of the first film system 120 and the second film system 200 in the first direction Z is reduced.

[0056] In an embodiment, the absorption rate of the first light-transmissive heat dissipation structure 130 in the gain wavelength range of the active layer 150 is less than or equal to 20%, for example, the absorption rate of the first light-transmissive heat dissipation structure 130 in the gain wavelength range of the active layer 150 is 20%, 15%, 10% or 5%; and the absorption rate of the second light-transmissive heat dissipation structure 170 in the gain wavelength range of the active layer 150 is less than or equal to 20%, for example, the absorption rate of the second light-transmissive heat dissipation structure 170 in the gain wavelength range of the active layer 150 is 20%, 15%, 10% or 5%. The absorption rate of the first light-transmissive heat dissipation structure 130 is smaller, and the absorption rate of the second light-transmissive heat dissipation structure 170 is smaller, thereby reducing optical loss.

[0057] In an embodiment, the material of the first light-transmissive heat dissipation structure 130 includes any one of diamond, silicon carbide, sapphire and graphene; and the material of the second light-transmissive heat dissipation structure 170 includes any one of diamond, silicon carbide, sapphire and graphene. The first light-transmissive heat dissipation structure 130 and the second light-transmissive heat dissipation structure 170 select these materials, so that the first light-transmissive heat dissipation structure 130 has higher thermal conductivity, and so that the second light-transmissive heat dissipation structure 170 has higher thermal conductivity, which is conducive to the heat dissipation of the active layer 150 by the first light-transmissive heat dissipation structure 130 and the second light-transmissive heat dissipation structure 170. Secondly, the first light-transmissive heat dissipation structure 130 and the second light-transmissive heat dissipation structure 170 select these materials, so that the absorption rate of the first light-transmissive heat dissipation structure 130 is smaller, and the absorption rate of the second light-transmissive heat dissipation structure 170 is smaller, thereby reducing optical loss.

[0058] In an embodiment, the semiconductor gain chip W further includes a first bonding layer 110 and a second bonding layer 180, the first bonding layer 110 is located between the first heat sink 100 and the first light-transmissive heat dissipation structure 130, and the second bonding layer 180 is located between the second heat sink 190 and the second light-transmissive heat dissipation structure 170.

[0059] In an embodiment, the material of the first bonding layer 110 can be selected from titanium, platinum, gold, indium, gold-tin and the like and compounds thereof. The material of the second bonding layer 180 can be selected from titanium, platinum, gold, indium, gold-tin and the like and compounds thereof.

[0060] In one embodiment, the semiconductor gain chip W further comprises a first semiconductor barrier layer 160 and a second semiconductor barrier layer 140, the first semiconductor barrier layer 160 is located between the active layer 150 and the second light-transmitting heat-dissipating structure 170, and the second semiconductor barrier layer 140 is located between the active layer 150 and the first light-transmitting heat-dissipating structure 130.

[0061] The material of the first semiconductor barrier layer 160 is different from the material of the active layer 150, and the material of the first semiconductor barrier layer 160 and the material of the active layer 150 have different etching selectivity ratios. Moreover, the material of the first semiconductor barrier layer 160 is different from the material of the second light-transmitting heat-dissipating structure 170. The first semiconductor barrier layer 160 is used to protect the active layer 150.

[0062] The material of the second semiconductor barrier layer 140 is different from the material of the active layer 150, and the material of the second semiconductor barrier layer 140 and the material of the active layer 150 have different etching selectivity ratios. Moreover, the material of the second semiconductor barrier layer 140 is different from the material of the first light-transmitting heat-dissipating structure 130. The second semiconductor barrier layer 140 is used to protect the active layer 150.

[0063] In one embodiment, the material of the first semiconductor barrier layer 160 comprises InGaP, AlGaAs or Si. The material of the second semiconductor barrier layer 140 comprises InGaP, AlGaAs or Si.

[0064] In one embodiment, the thickness of the first semiconductor barrier layer 160 in the first direction Z is 10 nm to 20 μm, for example, 40 nm to 60 nm; and the thickness of the second semiconductor barrier layer 140 in the first direction Z is 10 nm to 20 μm, for example, 40 nm to 60 nm. The range is selected in the sense that when the first semiconductor barrier layer 160 is thicker and the second semiconductor barrier layer 140 is thicker, the heat conduction of the active layer 150 is not conducive to further improvement, thereby limiting the further improvement of the output power; and when the first semiconductor barrier layer 160 is thinner and the second semiconductor barrier layer 140 is thinner, the protection of the active layer 150 is weaker.

[0065] In one embodiment, the active layer 150 comprises one or more active units, and each active unit comprises a plurality of quantum well layers and barrier layers which are alternately stacked in the first direction Z.

[0066] In one embodiment, the material of the quantum well layer comprises InGaAs, and the material of the barrier layer comprises GaAs.

[0067] In one embodiment, the material of the first heat sink 100 can be a metal heat sink, for example, copper; and the first heat sink can also be a semiconductor cooler (Thermoelectric Cooler).

[0068] In one embodiment, the material of the second heat sink 190 can be a metal heat sink, such as copper; the first heat sink can also be a thermoelectric cooler.

[0069] In one embodiment, the first film system 120 includes first films and second films alternately stacked in a first direction, the refractive index of the first films being greater than the refractive index of the second films. The second film system 200 includes third films and fourth films alternately stacked in the first direction, the refractive index of the third films being greater than the refractive index of the fourth films.

[0070] In one embodiment, the first film system 120 is a first dielectric film system, for example, the material of the first films is Ta2O5, and the material of the second films is SiO2. The second film system 200 is a second dielectric film system, for example, the material of the third films is Ta2O5, and the material of the fourth films is SiO2.

[0071] Since the materials of the first film system 120 and the second film system 200 are dielectric materials, they are easy to manufacture in the process and reduce the cost.

[0072] In another embodiment, the materials of the first films, the second films, the third films, and the fourth films can be semiconductor materials.

[0073] In one embodiment, the light output central wavelength of the optically pumped semiconductor laser is 980 nm or 1030 nm. In other embodiments, the light output central wavelength of the optically pumped semiconductor laser is not limited.

[0074] Another embodiment of the present application also provides a preparation method of an optically pumped semiconductor laser, including forming a semiconductor gain chip: wherein forming the semiconductor gain chip includes: forming an active layer on one side of a substrate along a first direction; disposing a first light-transmitting heat dissipation structure on the side of the active layer away from the substrate, and then removing the substrate; after removing the substrate, disposing a second light-transmitting heat dissipation structure on the side of the active layer away from the first light-transmitting heat dissipation structure; forming a first film system on part of the side of the first light-transmitting heat dissipation structure away from the active layer; forming a second film system on part of the surface of part of the second light-transmitting heat dissipation structure away from the active layer; the preparation method of the optically pumped semiconductor laser further includes: bonding a first heat sink on the side of part of the first light-transmitting heat dissipation structure away from the active layer, the first heat sink being located on the side of the first film system along a second direction; bonding a second heat sink on the side of part of the second light-transmitting heat dissipation structure away from the active layer, the second heat sink being located on the side of the second film system along the second direction; wherein the first direction is perpendicular to the second direction.

[0075] The fabrication method of the optically pumped semiconductor laser in this embodiment involves placing a first light-transmitting heat dissipation structure on the side of the active layer away from the substrate. After removing the substrate, a second light-transmitting heat dissipation structure is placed on the side of the active layer away from the first light-transmitting heat dissipation structure. That is, the first and second light-transmitting heat dissipation structures are respectively placed on both sides of the active layer along a first direction. This increases the spacing between the first and second film systems in the first direction and decreases the longitudinal mode spacing, i.e., reduces the wavelength difference between adjacent longitudinal modes. This suppresses the Fabry-Perot interference filtering effect between the first and second film systems and inhibits the effect of this effect on the active layer. The spectral modulation and filtering effects generated by the gain of the active layer allow for more longitudinal mode outputs within the gain wavelength range of the active layer, thereby increasing the gain spectral tuning range and facilitating wide-range wavelength tuning. Secondly, since the waste heat of the active layer is directly transferred to the first heat sink through the first transparent heat dissipation structure and directly transferred to the second heat sink through the second transparent heat dissipation structure, the first and second transparent heat dissipation structures have high thermal conductivity and adopt a double-sided heat dissipation method with a larger heat dissipation area. Therefore, the heat dissipation capability of the active layer is enhanced, which is conducive to heat extraction from the active layer and improves the output power of the optically pumped semiconductor laser.

[0076] In existing technologies, the fabrication of optically pumped external cavity surface-emitting semiconductor lasers involves sequentially growing a bottom Bragg mirror and an active layer on a substrate. During the growth of the active layer, lattice matching between the active layer material and the semiconductor Bragg mirror material is crucial; otherwise, the active layer will fail to emit light or exhibit poor performance, thus requiring complex processing techniques. In contrast, in this application, the formation of the first film system does not affect the lattice of the active layer, and the formation of the second film system does not affect the lattice of the active layer. This allows for greater freedom in the selection of materials for both the first and second film systems, reducing the material limitations imposed by the active layer on the first and second film systems.

[0077] In addition, in this application, the waste heat of the active layer can be transferred without relying on the first membrane system and the second membrane system. Therefore, the restrictions on the size of the first membrane system in the first direction and the size of the second membrane system in the first direction are reduced. The size of the first membrane system in the first direction can be selected according to the design requirements, and the size of the second membrane system in the first direction can be selected according to the design requirements.

[0078] Figure 7 This is a schematic diagram showing the formation of a first semiconductor barrier layer, an active layer, and a second semiconductor barrier layer on one side of the substrate along a first direction. Figure 8 This is a schematic diagram showing the first light-transmitting heat dissipation structure positioned on the side of the active layer away from the substrate. Figure 9 In order to be in Figure 8 A schematic diagram after removing the substrate; Figure 10This is a schematic diagram showing the second light-transmitting heat dissipation structure positioned on the side of the active layer away from the first light-transmitting heat dissipation structure. Figure 11 In order to be in Figure 10 A schematic diagram showing the formation of the first and second bonding layers on the foundation. Figure 12 for Figure 11 A bottom view; Figure 13 for Figure 11 Top view; Figure 14 In order to be in Figure 11 A schematic diagram showing the formation of the first and second membrane systems based on this. Figure 15 This is a schematic diagram showing the bonding of a first heat sink to the side of a portion of the first light-transmitting heat dissipation structure facing away from the active layer, and the bonding of a second heat sink to the side of a portion of the second light-transmitting heat dissipation structure facing away from the active layer.

[0079] refer to Figure 7 An active layer 150 is formed on one side of the substrate 300 along the first direction.

[0080] In one embodiment, the material of the substrate 300 is a semiconductor material, such as a GaAs substrate.

[0081] In one embodiment, the method for fabricating a semiconductor gain chip further includes forming a first semiconductor barrier layer 160 on one side of the substrate 300 along a first direction.

[0082] In one embodiment, the process of forming the first semiconductor barrier layer 160 includes an epitaxial growth process, such as a metal-organic chemical vapor deposition process or a molecular beam epitaxy process.

[0083] The material and thickness of the first semiconductor barrier layer 160 are as described in the foregoing embodiments.

[0084] In one embodiment, forming the active layer 150 includes forming the active layer 150 on the side of the first semiconductor barrier layer 160 away from the substrate 300.

[0085] In one embodiment, the method for fabricating a semiconductor gain chip further includes forming a second semiconductor barrier layer 140 on the side of the active layer 150 opposite to the first semiconductor barrier layer 160.

[0086] The material and thickness of the second semiconductor barrier layer 140 are as described in the foregoing embodiments.

[0087] The description of the active layer 150 is the same as that in the foregoing embodiments.

[0088] In one embodiment, one side surface of the active layer 150 along the first direction is in contact with the first semiconductor barrier layer 160, and the other side surface of the active layer 150 along the first direction is in contact with the second semiconductor barrier layer 140.

[0089] Reference Figure 8 The first light-transmissive heat-dissipation structure 130 is disposed on a side of the active layer 150 facing away from the substrate 300.

[0090] The first light-transmissive heat-dissipation structure 130 is disposed on a side of the active layer 150 facing away from the substrate 300, including: disposing the first light-transmissive heat-dissipation structure 130 on a side surface of the second semiconductor barrier layer 140 facing away from the active layer 150. Illustratively, the first light-transmissive heat-dissipation structure 130 is disposed on the side surface of the second semiconductor barrier layer 140 facing away from the active layer 150 by using a molecular inter-van der Waals force bonding process, a mechanical fixing process, a melting eutectic process, or an organic adhesion process.

[0091] The first light-transmissive heat-dissipation structure 130 is described with reference to the foregoing embodiments.

[0092] The first light-transmissive heat-dissipation structure 130 is disposed on a side surface of the second semiconductor barrier layer 140 facing away from the active layer 150, avoiding direct contact of the first light-transmissive heat-dissipation structure 130 with the active layer 150, and the second semiconductor barrier layer 140 can protect the active layer 150.

[0093] The material of the second semiconductor barrier layer 140 is different from the material of the active layer 150, and the material of the second semiconductor barrier layer 140 is different from the material of the first light-transmissive heat-dissipation structure 130.

[0094] Reference Figure 9 The first light-transmissive heat-dissipation structure 130 is disposed on a side surface of the active layer 150 facing away from the substrate 300, and then the substrate 300 is removed.

[0095] In one embodiment, the process of removing the substrate 300 includes an etching process, and the etching process includes one or a combination of a wet etching process and a dry etching process.

[0096] In one embodiment, the process of removing the substrate 300 is a wet etching process, and the etching solution of the wet etching process is a mixed solution of ammonia and hydrogen peroxide.

[0097] In one embodiment, removing the substrate 300 includes removing the substrate 300 with the first semiconductor barrier layer 160 as an etching stop layer.

[0098] The material of the first semiconductor barrier layer 160 is different from the material of the active layer 150 and the material of the substrate 300, and the material of the first semiconductor barrier layer 160 and the material of the active layer 150 have a certain etching ratio during the process of removing the substrate 300. The first semiconductor barrier layer 160 acts as an etching barrier layer to protect the active layer 150 and reduce etching damage to the active layer 150.

[0099] In the process of removing the substrate 300, the first light-transmissive heat-dissipation structure 130 can be used as a support carrier.

[0100] In one embodiment, the material of the first light-transmissive heat-dissipation structure 130 is different from the material of the substrate 300, and in the process of removing the substrate 300, the first light-transmissive heat-dissipation structure 130 is less damaged by etching.

[0101] With reference to Figure 10 , after removing the substrate 300, the second light-transmissive heat-dissipation structure 170 is arranged on the side of the active layer 150 away from the first light-transmissive heat-dissipation structure 130.

[0102] The second light-transmissive heat-dissipation structure 170 is arranged on the side of the active layer 150 away from the first light-transmissive heat-dissipation structure 130, including: arranging the second light-transmissive heat-dissipation structure 170 on the side surface of the first semiconductor barrier layer 160 away from the active layer 150. Illustratively, the second light-transmissive heat-dissipation structure 170 is arranged on the side surface of the first semiconductor barrier layer 160 away from the active layer 150 by using a molecular van der Waals force bonding process, a mechanical fixing process, a fusion eutectic process or an organic adhesion process.

[0103] Arranging the second light-transmissive heat-dissipation structure 170 on the side surface of the first semiconductor barrier layer 160 away from the active layer 150 avoids direct contact between the second light-transmissive heat-dissipation structure 170 and the active layer 150, and the first semiconductor barrier layer 160 can protect the active layer 150.

[0104] The second light-transmissive heat-dissipation structure 170 is described with reference to the foregoing embodiments.

[0105] With reference to Figure 11 , Figure 12 and Figure 13 , a first bonding layer 110 is formed on part of the side surface of the first light-transmissive heat-dissipation structure 130 away from the active layer 150; and a second bonding layer 180 is formed on part of the side surface of the second light-transmissive heat-dissipation structure 170 away from the active layer 150. Figure 12 Fig. 1 is a bottom view of the semiconductor device 100, Figure 11 Fig. 2 is a top view of the semiconductor device 100. Figure 13 Figure 11 Fig. 3 is a cross-sectional view of the semiconductor device 100.

[0106] Illustratively, the first bonding layer 110 is formed on the side surface of the edge region of the first light-transmissive heat-dissipation structure 130 away from the active layer 150. The second bonding layer 180 is formed on the side surface of the edge region of the second light-transmissive heat-dissipation structure 170 away from the active layer 150.

[0107] ​In one embodiment, the first bonding layer 110 is formed on a side surface of the first light-transmissive heat dissipation structure 130 away from the active layer 150, comprising: forming a first bonding material layer on a side surface of the first light-transmissive heat dissipation structure 130 away from the active layer 150; etching the first bonding material layer to form the first bonding layer 110.

[0108] In one embodiment, the second bonding layer 180 is formed on a side surface of the second light-transmissive heat dissipation structure 170 away from the active layer 150, comprising: forming a second bonding material layer on a side surface of the second light-transmissive heat dissipation structure 170 away from the active layer 150; etching the second bonding material layer to form the second bonding layer 180.

[0109] The first bonding layer 110 exposes a central region of the first light-transmissive heat dissipation structure 130. The second bonding layer 180 exposes a central region of the second light-transmissive heat dissipation structure 170.

[0110] The material of the first bonding layer 110 and the second bonding layer 180 is referred to the aforementioned embodiments.

[0111] Reference Figure 14 In one embodiment, the first film system 120 is formed on a side surface of the first light-transmissive heat dissipation structure 130 away from the active layer 150; the second film system 200 is formed on a side surface of the second light-transmissive heat dissipation structure 170 away from the active layer 150.

[0112] For example, the first film system 120 is formed on a side surface of a central region of the first light-transmissive heat dissipation structure 130 away from the active layer 150; the second film system 200 is formed on a side surface of a central region of the second light-transmissive heat dissipation structure 170 away from the active layer 150.

[0113] In one embodiment, the process of forming the first film system 120 comprises a thermal evaporation plating process, an electron beam evaporation plating process, or an ion beam assisted deposition process. The process of forming the second film system 200 comprises a thermal evaporation plating process, an electron beam evaporation plating process, or an ion beam assisted deposition process.

[0114] After forming the first film system 120, the first bonding layer 110 surrounds a sidewall of the first film system 120. After forming the second film system 200, the second bonding layer 180 surrounds a sidewall of the second film system 200.

[0115] In one embodiment, the first film system 120 is formed on a side surface of the first light-transmissive heat dissipation structure 130 away from the active layer 150 by using a thermal evaporation plating process, an electron beam evaporation plating process, or an ion beam assisted deposition process. The second film system 200 is formed on a side surface of the second light-transmissive heat dissipation structure 170 away from the active layer 150 by using a thermal evaporation plating process, an electron beam evaporation plating process, or an ion beam assisted deposition process.

[0116] In one embodiment, the first film system 120 can be formed on one side surface of the first temporary substrate by a thermal evaporation process, an electron beam evaporation process, or an ion beam assisted deposition process, and then the first film system 120 can be bonded to the center region of the first light-transmissive heat dissipation structure 130 away from the active layer 150, for example, by intermolecular van der Waals force, and then the first temporary substrate can be removed.

[0117] In one embodiment, the second film system 200 can be formed on one side surface of the second temporary substrate by a thermal evaporation process, an electron beam evaporation process, or an ion beam assisted deposition process, and then the second film system 200 can be bonded to the center region of the second light-transmissive heat dissipation structure 170 away from the active layer 150, for example, by intermolecular van der Waals force, and then the second temporary substrate can be removed.

[0118] In the present application, the first film system 120 and the second film system 200 are formed after the active layer 150 is formed, so that the process of forming the first film system 120 does not affect the lattice of the active layer 150, and the process of forming the second film system 200 does not affect the lattice of the active layer 150. This makes the material selection of the first film system 120 and the second film system 200 have higher freedom, and reduces the material limitation of the active layer 150 on the materials of the first film system 120 and the second film system 200.

[0119] The first film system 120 and the second film system 200 are described with reference to the foregoing embodiments.

[0120] Reference Figure 15 The first heat sink 100 is bonded to part of the first light-transmissive heat dissipation structure 130 away from the active layer 150, and the first heat sink 100 is located at the side of the first film system 120 along the second direction; and the second heat sink 190 is bonded to part of the second light-transmissive heat dissipation structure 170 away from the active layer 150, and the second heat sink 190 is located at the side of the second film system 200 along the second direction.

[0121] The bonding of the first heat sink 100 to part of the first light-transmissive heat dissipation structure 130 away from the active layer 150 includes bonding the first heat sink 100 to the side surface of the first bonding layer 110 away from the first light-transmissive heat dissipation structure 130.

[0122] The bonding of the second heat sink 190 on the side of the second light-transmissive heat dissipation structure 170 away from the active layer 150 includes: bonding the second heat sink 190 and the second bonding layer 180 together on the side surface of the second light-transmissive heat dissipation structure 170.

[0123] The first heat sink 100 and the second heat sink 190 refer to the description of the foregoing embodiments.

[0124] In one embodiment, the first film system 120 is a first anti-reflection film system, and the second film system 200 is a second anti-reflection film system. The preparation method further includes: Figure 2 The mirror 301 is arranged on the side of the second film system 200 and the second heat sink 190 away from the active layer 150 and is spaced apart from the semiconductor gain chip W and the second heat sink 190, and the output mirror 400 is arranged on the side of the first film system 120 and the first heat sink 100 away from the active layer 150 and is spaced apart from the semiconductor gain chip W and the first heat sink 100. The resonant cavity is formed between the mirror 301 and the output mirror 400.

[0125] In one embodiment, when the first film system 120 is a first anti-reflection film system and the second film system 200 is a second anti-reflection film system, the reflectivity of the first film system 120 at the central wavelength of the light-pumped semiconductor laser light emission is less than or equal to 0.2%, and the reflectivity of the second film system 200 at the central wavelength of the light-pumped semiconductor laser light emission is less than or equal to 0.2%.

[0126] When the first film system 120 is a first anti-reflection film system and the second film system 200 is a second anti-reflection film system, the reflectivity of the first film system 120 to the active layer 150 gain wavelength and the reflectivity of the second film system 200 to the active layer 150 gain wavelength are both small, which suppresses the Fabry-Perot interference filtering effect between the first film system 120 and the second film system 200, and suppresses the filtering effect between the mirror 301 and the output mirror 400, thereby further increasing the gain spectrum tuning range and further realizing wide-range wavelength tuning.

[0127] In another embodiment, referring to Figure 6 , the first film system 120 is a first Bragg mirror, the second film system 200 is a second Bragg mirror, the reflectivity of the second Bragg mirror is greater than the reflectivity of the first Bragg mirror, and the resonant cavity is formed between the second film system 200 and the first film system 120.

[0128] In another embodiment, referring to Figure 4The first film system 120 is a reflection-reducing film system, and the second film system 200 is a reflection film system; wherein the preparation method of the optically pumped semiconductor laser further comprises: disposing an output mirror 400 on the side of the first film system 120 and the first heat sink 100 away from the active layer 150 and spaced apart from the semiconductor gain chip W and the first heat sink 100; and forming a resonant cavity between the second film system 200 and the output mirror 400. When the first film system 120 is a reflection-reducing film system, the reflectivity of the first film system 120 to the gain wavelength of the active layer 150 is small, so that the Fabry-Perot interference filtering effect between the first film system 120 and the second film system 200 is inhibited, and the filtering effect between the second film system 200 and the output mirror 400 is inhibited, so that the gain spectrum tuning range is further increased, and wide-range wavelength tuning is further achieved.

[0129] Obviously, the above embodiments are merely exemplary and are not intended to limit the embodiments. Based on the above description, one of ordinary skill in the art can make other different forms of changes or modifications. All the embodiments do not need to be exhausted, and the obvious changes or modifications derived therefrom are still within the protection scope of the present application.

Claims

1. An optically pumped semiconductor laser, characterized in that, Includes a semiconductor gain chip, a first heat sink, and a second heat sink; The semiconductor gain chip includes: Active layer; The first light-transmitting heat dissipation structure is located on one side of the active layer along the first direction; The second light-transmitting heat dissipation structure is located on the other side of the active layer along the first direction; A first film system is located on the surface of a portion of the first light-transmitting and heat-dissipating structure opposite to the active layer; and The second film system is located on the surface of a portion of the second light-transmitting heat dissipation structure opposite to the active layer; Wherein, the first heat sink is located on the side of the first light-transmitting heat dissipation structure away from the active layer, and the first heat sink is located on the side of the first film system along the second direction; the second heat sink is located on the side of the second light-transmitting heat dissipation structure away from the active layer, and the second heat sink is located on the side of the second film system along the second direction. Wherein, the first direction and the second direction are perpendicular.

2. The optically pumped semiconductor laser according to claim 1, characterized in that, The thickness of the first light-transmitting heat dissipation structure in the first direction is greater than the thickness of the first film system in the first direction, and the thickness of the second light-transmitting heat dissipation structure in the first direction is greater than the thickness of the second film system in the first direction.

3. The optically pumped semiconductor laser according to claim 1, characterized in that, The thickness of the first light-transmitting heat dissipation structure in the first direction is 500nm~10mm; the thickness of the second light-transmitting heat dissipation structure in the first direction is 500nm~10mm.

4. The optically pumped semiconductor laser according to claim 1, characterized in that, The material of the first light-transmitting heat dissipation structure includes any one of diamond, silicon carbide, sapphire, and graphene; the material of the second light-transmitting heat dissipation structure includes any one of diamond, silicon carbide, sapphire, and graphene.

5. The optically pumped semiconductor laser according to claim 1, characterized in that, The thermal conductivity of the first light-transmitting heat dissipation structure is greater than that of the first film system, and the thermal conductivity of the second light-transmitting heat dissipation structure is greater than that of the second film system.

6. The optically pumped semiconductor laser according to claim 1, characterized in that, The first light-transmitting heat dissipation structure has an absorption rate of less than or equal to 20% within the gain wavelength range of the active layer; the second light-transmitting heat dissipation structure has an absorption rate of less than or equal to 20% within the gain wavelength range of the active layer.

7. The optically pumped semiconductor laser according to claim 1, characterized in that, The semiconductor gain chip further includes: a first bonding layer located between the first heat sink and the first light-transmitting heat dissipation structure; and a second bonding layer located between the second heat sink and the second light-transmitting heat dissipation structure.

8. The optically pumped semiconductor laser according to claim 1, characterized in that, The semiconductor gain chip further includes: a first semiconductor blocking layer located between the active layer and the second light-transmitting heat dissipation structure; and a second semiconductor blocking layer located between the active layer and the first light-transmitting heat dissipation structure.

9. The optically pumped semiconductor laser according to claim 8, characterized in that, The thickness of the first semiconductor barrier layer in the first direction is 10 nm to 20 μm; The thickness of the second semiconductor barrier layer in the first direction is 10 nm to 20 μm.

10. The optically pumped semiconductor laser according to claim 1, characterized in that, The first film system is a first antireflective film system, and the second film system is a second antireflective film system; The optically pumped semiconductor laser further includes a reflector and an output mirror; the reflector is located on the side of the second film system and the second heat sink away from the active layer and is spaced apart from the semiconductor gain chip and the second heat sink; the output mirror is located on the side of the first film system and the first heat sink away from the active layer and is spaced apart from the semiconductor gain chip and the first heat sink; a resonant cavity is formed between the reflector and the output mirror.

11. The optically pumped semiconductor laser according to claim 1, characterized in that, The first film system is a first Bragg reflector, the second film system is a second Bragg reflector, the reflectivity of the second Bragg reflector is greater than that of the first Bragg reflector, and the second film system and the first film system form a resonant cavity.

12. The optically pumped semiconductor laser according to claim 1, characterized in that, The first film system is an antireflective film system, and the second film system is a reflective film system; The optically pumped semiconductor laser further includes: an output mirror located on the side of the first film system and the first heat sink away from the active layer and spaced apart from the semiconductor gain chip and the first heat sink; and a resonant cavity is formed between the second film system and the output mirror.

13. A method for fabricating an optically pumped semiconductor laser, characterized in that, include: Forming a semiconductor gain chip includes: forming an active layer on one side of a substrate along a first direction; disposing a first light-transmitting heat dissipation structure on the side of the active layer opposite to the substrate; then removing the substrate; after removing the substrate, disposing a second light-transmitting heat dissipation structure on the side of the active layer opposite to the first light-transmitting heat dissipation structure; forming a first film system on a portion of the surface of the first light-transmitting heat dissipation structure opposite to the active layer; forming a second film system on a portion of the surface of the second light-transmitting heat dissipation structure opposite to the active layer; and... The first heat sink is bonded to a portion of the first light-transmitting heat dissipation structure on the side opposite to the active layer, and the first heat sink is located on the side of the first film system along the second direction. The second heat sink is bonded to a portion of the second light-transmitting heat dissipation structure on the side opposite to the active layer, and the second heat sink is located on the side of the second film system along the second direction. Wherein, the first direction is perpendicular to the second direction.

14. The method for fabricating an optically pumped semiconductor laser according to claim 13, characterized in that, The formation of a semiconductor gain chip also includes: A first semiconductor barrier layer is formed on one side of the substrate along the first direction; The formation of the active layer includes: forming the active layer on the side of the first semiconductor barrier layer away from the substrate; The removal of the substrate includes: removing the substrate using the first semiconductor barrier layer as an etch stop layer; The provision of the second light-transmitting heat dissipation structure on the side of the active layer away from the first light-transmitting heat dissipation structure includes: the second light-transmitting heat dissipation structure being disposed on the surface of the first semiconductor barrier layer away from the active layer.

15. The method for fabricating an optically pumped semiconductor laser according to claim 14, characterized in that, The semiconductor gain chip is further formed by: forming a second semiconductor barrier layer on the side of the active layer opposite to the first semiconductor barrier layer; The provision of the first light-transmitting heat dissipation structure on the side of the active layer away from the substrate includes: the first light-transmitting heat dissipation structure being disposed on the surface of the second semiconductor barrier layer away from the active layer.

16. The method for fabricating an optically pumped semiconductor laser according to claim 13, characterized in that, The semiconductor gain chip formation further includes: forming a first bonding layer on a portion of the first light-transmitting heat dissipation structure on the side surface opposite to the active layer; forming a second bonding layer on a portion of the second light-transmitting heat dissipation structure on the side surface opposite to the active layer; wherein, after the first film system is formed, the first bonding layer surrounds the sidewall of the first film system; after the second film system is formed, the second bonding layer surrounds the sidewall of the second film system. The first heat sink is bonded to the side of the first light-transmitting heat dissipation structure opposite to the active layer, which includes: bonding the first heat sink to the surface of the first bonding layer opposite to the first light-transmitting heat dissipation structure. The step of bonding the second heat sink to a portion of the second light-transmitting heat dissipation structure on the side away from the active layer includes: bonding the second heat sink to the surface of the second bonding layer on the side away from the second light-transmitting heat dissipation structure.

17. The method for fabricating an optically pumped semiconductor laser according to claim 13, characterized in that, The first film system is a first antireflective film system, and the second film system is a second antireflective film system; The fabrication method of the optically pumped semiconductor laser further includes: placing a reflector on the side of the second film system and the second heat sink away from the active layer and spaced apart from the semiconductor gain chip and the second heat sink; placing an output mirror on the side of the first film system and the first heat sink away from the active layer and spaced apart from the semiconductor gain chip and the first heat sink; and forming a resonant cavity between the reflector and the output mirror.

18. The method for fabricating an optically pumped semiconductor laser according to claim 13, characterized in that, The first film system is a first Bragg reflector, the second film system is a second Bragg reflector, the reflectivity of the second Bragg reflector is greater than that of the first Bragg reflector, and the second film system and the first film system form a resonant cavity.

19. The method for fabricating an optically pumped semiconductor laser according to claim 13, characterized in that, The first film system is an antireflective film system, and the second film system is a reflective film system; The method for fabricating the optically pumped semiconductor laser further includes: placing an output mirror on the side of the first film system and the first heat sink away from the active layer and spaced apart from the semiconductor gain chip and the first heat sink; and forming a resonant cavity between the second film system and the output mirror.

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