TWI791217B - Photonic crystal surface emitting laser device - Google Patents

Abstract

A photonic crystal surface emitting laser device including at least one photonic crystal surface emitting laser unit is provided. The photonic crystal surface emitting laser unit includes a light-emitting layer, a photonic crystal layer, a doped semiconductor layer, and a diffractive grating. The light-emitting layer is configured to emit a light beam. The photonic crystal layer is disposed on one side of the light-emitting layer. The doped semiconductor layer is disposed on another side of the light-emitting layer. The diffractive grating is disposed on the photonic crystal layer or the doped semiconductor layer.

Description

Photonic crystal surface emitting laser element

The present invention relates to a laser component, and in particular to a photonic crystal surface-emitting laser component.

Electroluminescent photonic crystal surface-emitting laser can achieve single mode output, narrow spectrum wavelength linewidth and small light divergence angle. Its main structure includes a bottom cladding layer (bottom cladding layer), a light-emitting layer and a photonic crystal layer, wherein the light-emitting layer is located between the bottom cladding layer and the photonic crystal layer. Under this structure and operation mechanism, the laser light will be emitted to the outside from at least one of the top and bottom directions.

If combined with micro-electromechanical system (MEMS) optical elements or mechanical swing optical elements to make the photonic crystal surface-emitting laser generate dynamic deflection, the scanning effect can be achieved. However, both micro-electro-mechanical systems and mechanical oscillating optical components use mechanical oscillating methods to achieve the scanning effect, and there are problems that the scanning speed is limited by the mechanical oscillating speed, and the reliability and durability of the components are not good enough.

The invention provides a photonic crystal surface-emitting laser element, which can determine the light deflection direction of the laser beam by using a simple structure.

An embodiment of the present invention proposes a photonic crystal surface-emitting laser device, which includes at least one photonic crystal surface-emitting laser unit. The photonic crystal surface-emitting laser unit includes a light-emitting layer, a photonic crystal layer, a doped A semiconductor layer and a diffraction grating. The light-emitting layer is used to emit a light beam, and the photonic crystal layer is arranged on one side of the light-emitting layer. The doped semiconductor layer is arranged on the other side of the light emitting layer, and the diffraction grating is arranged on the photonic crystal layer or the doped semiconductor layer.

In the photonic crystal surface-emitting laser element of the embodiment of the present invention, since the diffraction grating configured on the photonic crystal layer or the doped semiconductor layer is used to diffract the laser beam diffracted by the photonic crystal layer, Therefore, a simple structure can be used to determine the light deflection direction of the laser beam.

Fig. 1A is a schematic perspective view of a photonic crystal surface-emitting laser device according to an embodiment of the present invention, Fig. 1B is a schematic top view of the photonic crystal surface-emitting laser device of Fig. 1A, and Fig. 1C is a photonic crystal of Fig. 1B A schematic cross-sectional view of a surface-emitting laser device along the line I-I. In Figure 1A, the top of the photonic crystal surface-emitting laser device is partially cut away to illustrate part of its internal structure. Please refer to Fig. 1A, Fig. 1B and Fig. 1C, the photonic crystal surface-emitting type laser device 200 of the present embodiment comprises at least one photonic crystal surface-emitting type laser unit 100 (Fig. 1A to Fig. 1C are a photonic crystal surface-emitting type The laser unit 100 is taken as an example), the photonic crystal surface-emitting laser unit 100 includes a light emitting layer 120 , a photonic crystal layer 130 , a doped semiconductor layer 110 and a diffraction grating 300 . The light-emitting layer 120 is used to emit a light beam 122. In this embodiment, the light-emitting layer 120 includes a quantum well layer, a multiple quantum well (multiple quantum well) layer or a quantum dot (quantum dot) layer, and the light beam 122 emitted by it can be Infrared light, visible light or ultraviolet light.

The photonic crystal layer 130 is disposed on one side of the light emitting layer 120 , and the doped semiconductor layer 110 is disposed on the other side of the light emitting layer 120 . In this embodiment, the photonic crystal layer 130 is a P-type semiconductor layer, and the doped semiconductor layer 110 is an N-type semiconductor layer. However, in other embodiments, the photonic crystal layer 130 may also be an N-type semiconductor layer, and the doped semiconductor layer 110 may be a P-type semiconductor layer. In addition, the diffraction grating 300 is disposed on the photonic crystal layer 130 or the doped semiconductor layer 110 , and FIG. 1A and FIG. 1C are disposed on the photonic crystal layer 130 as an example.

In this embodiment, the photonic crystal surface-emitting laser device 200 further includes a first electrode 140 electrically connected to the doped semiconductor layer 110, wherein the photonic crystal surface-emitting laser unit 100 further includes a second electrode 150 , disposed on the photonic crystal layer 130 and electrically connected to the photonic crystal layer 130 . In this embodiment, by applying a forward bias voltage on the second electrode 150 and the first electrode 140, the holes in the photonic crystal layer 130 and the electrons in the doped semiconductor layer 110 can be transferred to the light emitting layer 120, and recombine in the luminescent layer 120 to generate a light beam 122 .

The light beam 122 emitted by the light-emitting layer 120 generates resonance in the horizontal direction in FIG. 1C in the photonic crystal layer 130, and the photonic crystal layer 130 may include a second-order grating structure, which directs the light beam 122 to the vertical direction in FIG. 1C. Direction guidance, and transfer to the top and bottom in Figure 1C. That is to say, the luminescent layer 120 is a gain medium that emits a light beam 122 and provides optical gain. After the light beam 122 enters the photonic crystal layer 130 to generate diffraction resonance, a vertically radiated laser beam is generated. In addition, the structure of the second-order grating can be a structure with a two-dimensional hole array. In other embodiments, the photonic crystal layer 130 may also have a grating structure with more than three levels. In addition, the photonic crystal layer 130 may also be a one-dimensional grating structure. The light beam 122 is diffracted by the photonic crystal layer 130 and the diffraction grating 300 , and then emerges from the photonic crystal surface-emitting laser unit 100 . In other embodiments, the photonic crystal layer 130 may also include a two-dimensional array of two circular or rectangular holes in pairs, an array of triangular holes, or other various possible photonic crystal structures.

In the photonic crystal surface-emitting laser element 200 of this embodiment, since the diffraction grating 300 disposed on the photonic crystal layer 130 or the doped semiconductor layer 110 is used to diffract the beam diffracted by the photonic crystal layer 130 122 (that is, the laser beam), so a simple structure can be used to determine the light deflection direction of the light beam 122 (that is, the laser beam).

In this embodiment, a part of the second electrode 150 is a diffraction grating 300 . For example, as shown in FIG. 1A and FIG. 1C , the central portion of the second electrode 150 is formed with periodically arranged elongated slits 152 to form a diffraction grating 300 . However, in other embodiments, the center of the second electrode 150 may have an opening, and the opening is provided with a diffraction grating 300 formed of a material different from that of the second electrode 150. The material of the diffraction grating 300 may be metal, semiconductor or oxide.

In this embodiment, the photonic crystal surface-emitting laser unit 100 further includes a transparent conductive layer 170 disposed between the photonic crystal layer 130 and the second electrode 150 to electrically connect the photonic crystal layer 130 and the second electrode 150 . In this embodiment, the photonic crystal surface-emitting laser device 200 further includes a substrate 160 disposed between the doped semiconductor layer 110 and the first electrode 140 and electrically connected to the doped semiconductor layer 110 and the first electrode 140 , and the substrate 160 has conductivity.

In this embodiment, the photonic crystal layer 130 includes a cladding layer 132 , a graded index layer (GRIN layer) 136 and an ohmic contact layer 134 . The cladding layer 132 is disposed on the light emitting layer 120 , and the graded index of refraction layer 136 is disposed on the cladding layer 132 . The ohmic contact layer 134 is disposed between the graded refractive index layer 136 and the transparent conductive layer 170, and is in contact with the transparent conductive layer 170 to form an ohmic contact, wherein the cladding layer 132, the graded refractive index layer 136 and the ohmic contact layer 134 have photonic crystals structure. For example, the photonic crystal layer 130 has a plurality of through holes 131 located in the cladding layer 132, the graded index layer 136 and the ohmic contact layer 134, and extending from the cladding layer 132 to the ohmic contact layer 134 to form photonic crystals. structure. In this embodiment, the through hole 131 penetrates through the ohmic contact layer 134 , the graded index of refraction layer 136 and the cladding layer 132 . In addition, in one embodiment, the through holes 131 may be arranged in a two-dimensional array in a direction parallel to the substrate 160 . In this embodiment, the photonic crystal surface-emitting laser unit 100 further includes a current confinement layer 180 disposed between the photonic crystal layer 130 and the transparent conductive layer 170, and has an opening 182, wherein the transparent conductive layer 170 passes through the opening. 182 to connect to the photonic crystal layer 130 .

In this embodiment, the photonic crystal surface-emitting laser unit 100 further includes a graded index layer 190 disposed between the substrate 160 and the doped semiconductor layer 110 , wherein the doped semiconductor layer 110 is a cladding layer.

In addition, in FIG. 1B, the periodic direction P1 of the diffraction grating 300 is along the direction of the I-I line. However, in other embodiments, as shown in FIG. 1D and FIG. 1E, the periodic direction P1 of the diffraction grating 300 can also be It is along other directions according to the actually required deflection direction of the light beam 122 .

Please refer to FIG. 1A to FIG. 1C again. The present invention does not limit the material of each film layer. In some embodiments, the material of the substrate 160 can be gallium nitride (gallium nitride, GaN), gallium arsenide (gallium arsenide, GaAs ), indium phosphide (InP), gallium antimonide (GaSb), indium arsenide (indium arsenide, InAs) or other suitable materials. In other embodiments, when the first electrode 140 can be electrically connected to the doped semiconductor layer 110 without being electrically connected to the doped semiconductor layer 110 through the substrate 160, the substrate 160 can be a semi-insulating substrate or an insulating substrate, Such as sapphire substrate (sapphire substrate). The material of the light emitting layer 120 may include gallium nitride, aluminum gallium nitride (AlGaN), gallium arsenide, indium gallium arsenide (indium gallium arsenide, InGaAs), aluminum gallium arsenide (aluminum gallium arsenide, AlGaAs) , gallium phosphide (gallium phosphide, GaP), indium arsenide (indium arsenide, InAs), indium arsenic antimonide (InAsSb), indium gallium arsenic antimonide (InGaAsSb), aluminum antimonide Gallium arsenic (aluminum gallium arsenic antimonide, AlGaAsSb), indium gallium arsenide phosphide (InGaAsP), aluminum indium gallium arsenide (aluminum indium gallium arsenide, AlInGaAs) other appropriate semiconductor materials or combinations thereof, and the light-emitting layer 120 can use more than two different materials or more than two materials of the same compound but with different element ratios to form a quantum well layer, a variety of quantum well layers or a quantum dot structure. The cladding layer 132, the doped semiconductor layer 110, and the graded-index layers 136 and 190 are made of, for example, aluminum gallium arsenide (aluminum gallium arsenide, AlGaAs), gallium arsenide, aluminum gallium nitride, aluminum gallium indium arsenide (aluminum gallium arsenide, gallium indium arsenide, AlGaInAs), aluminum gallium indium phosphide (aluminum gallium indium phosphide, AlGaInP), aluminum gallium antimonide arsenide or other suitable materials. The material of the ohmic contact layer 134 may be gallium nitride, gallium arsenide, indium gallium arsenide phosphide (InGaAsP), indium gallium arsenide (indium gallium arsenide, InGaAs) or other suitable materials. In addition, the ohmic contact layer 134 can be heavily doped with beryllium (beryllium), carbon (carbon), zinc (zinc) or a combination thereof to form P-type doping, so as to have a good ohmic contact with the transparent conductive layer 170, wherein the beryllium doped The concentration can be about 10 ¹⁹ cm ^-3 , while the carbon doping concentration can be about 10 ¹⁹ cm ^-3 to 10 ²⁰ cm ^-3 , and the zinc doping concentration can be about 10 ¹⁹ cm ^-3 to 10 ²⁰ cm ^{- 3} , but the present invention is not limited thereto. The material of the current confinement layer 180 can be silicon nitride, silicon oxide or other suitable materials. The current confinement layer 180 can block the current so that the current concentrates on the opening 182 and passes through the opening 182 .

The material of the transparent conductive layer 170 is, for example, indium tin oxide (indium tin oxide, ITO), antimony tin oxide (antimony tin oxide, ATO), fluorine doped tin oxide (fluorine doped tin oxide, FTO), aluminum zinc oxide (aluminum zinc oxide, AZO), gallium zinc oxide (GZO), indium zinc oxide (IZO), zinc oxide (ZnO), graphene or other appropriate transparent conductive materials. The first electrode 140 and the second electrode 150 can be metal electrodes, and their materials are, for example, gold, titanium-gold alloy, titanium-platinum alloy, nickel-germanium-gold alloy, or other suitable metals. The transparent conductive layer 170 can conduct current so that the current concentrates through the opening 182 , and at the same time, the transparent conductive layer 170 can also allow the light beam 122 emitted by the light emitting layer 120 to pass through without blocking the light beam 122 .

In addition, in an embodiment, in each of the above film layers, the P-type doping can be beryllium, carbon, zinc or a combination thereof, and the doping concentration is about 10 ¹⁷ cm ^-3 to 10 ¹⁸ cm ^{- 3} (except that the doping concentration of the ohmic contact layer 134 is about 10 ¹⁹ cm ^-3 to 10 ²⁰ cm ^-3 ), and the N-type doping can be doped silicon, and its doping concentration is about 10 ¹⁷ cm ^-3 to 10 ¹⁸ cm ^-3 , but the present invention is not limited thereto. In other embodiments, other appropriate elements can also be doped to achieve P-type doping and N-type doping.

In this embodiment, the substrate 160, the graded index layer 190, and the doped semiconductor layer 110 are all N-type doped semiconductor layers, and the photonic crystal layer 130 includes a cladding layer 132, a graded index layer 136, and an ohmic contact layer 134. Both are P-type doped semiconductor layers. However, in other embodiments, the substrate 160, the graded index layer 190 and the doped semiconductor layer 110 may all be P-type doped semiconductor layers, and the cladding layer 132, the graded index layer 136 and the ohmic contact layer 134 Both are N-type doped semiconductor layers.

The material of the diffraction grating 300 can be metal, silicon, semiconductor, transparent conductive layer (such as indium tin oxide, indium zinc oxide or aluminum zinc oxide, etc.). The diffraction grating 300 can be a one-dimensional grating (for example, in the form of stripes) or a two-dimensional grating (for example, in the form of a line array, hole array, columnar array or polygonal array), or a microlens array.

Fig. 2A is a schematic cross-sectional view of a photonic crystal surface-emitting laser element according to another embodiment of the present invention, and Fig. 2B is a simplified three-dimensional schematic diagram of the photonic crystal layer, the diffraction grating surface of the transparent conductive layer and the diffraction grating in Fig. 2A . Please refer to FIG. 2A and FIG. 2B , the photonic crystal surface-emitting laser device 200 a of this embodiment is similar to the photonic crystal surface-emitting laser device 200 in FIG. 1C , and the differences between the two are as follows. In the photonic crystal surface-emitting laser unit 100a of the photonic crystal surface-emitting laser device 200a, the surface of the transparent conductive layer 170a facing away from the light-emitting layer 120 is a diffraction grating surface 172a. The periodic direction of the diffraction grating surface 172a and the periodic direction of the diffraction grating 300 can be the same or different, and FIG. example. The light beam 122 diffracts twice with the diffraction grating 300 through the diffraction grating surface 172a, and more changes can be produced in the deflection angle. For example, as shown in FIG. 2B , the light beam 122 can be divided into two after being diffracted by the diffraction grating surface 172a, and the two beams 122 are then diffracted by the diffraction grating 300 to form a total Four light beams 122 are branched off. The angle of the split beam 122 can be controlled by the period of the diffraction grating. In contrast to the photonic crystal surface-emitting laser device 200 shown in Figure 1C, since the surface of the transparent conductive layer 170 facing away from the light-emitting layer 120 is a smooth surface, the light beam 122 only passes through the diffraction effect of the diffraction grating 300 and separates into two paths. Beam 122.

In this embodiment, the diffraction grating surface 172a can be naturally formed by the deposition process of the transparent conductive layer 170a when depositing a thicker transparent conductive layer 170a, or can be additionally formed by an etching process.

In one embodiment, the diffraction grating surface 172a can be a one-dimensional grating (such as in the shape of stripes) or a two-dimensional grating (such as in the shape of a line array, a hole array, a column array or a polygon array), or it can be is a microlens array.

FIG. 3 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Please refer to FIG. 3 , the photonic crystal surface-emitting laser device 200 c of this embodiment is similar to the photonic crystal surface-emitting laser device 200 shown in FIG. 1C , and the differences between the two are as follows. The photonic crystal surface-emitting laser unit 100c of the photonic crystal surface-emitting laser device 200c of the present embodiment further includes a distributed Bragg reflector (DBR) 195 disposed between the doped semiconductor layer 110 and the substrate 160 3 to reflect the light beam 122 diffracted from the photonic crystal layer 130 toward the bottom of FIG. 3 toward the diffraction grating 300 . In this way, the light energy of the light beam 122 emitted from the diffraction grating 300 can be increased to achieve better light utilization efficiency.

FIG. 4 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Referring to FIG. 4 , the photonic crystal surface-emitting laser device 200 d of this embodiment is similar to the photonic crystal surface-emitting laser device 200 shown in FIG. 1C , and the differences between the two are as follows. In the photonic crystal surface-emitting laser unit 100d of the photonic crystal surface-emitting laser device 200d of this embodiment, the doped semiconductor layer 110 and the first electrode 140 are disposed on the same side of the substrate 160 .

FIG. 5 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Referring to FIG. 5 , the photonic crystal surface-emitting laser device 200 e of this embodiment is similar to the photonic crystal surface-emitting laser device 200 shown in FIG. 1C , and the differences between the two are as follows. In the photonic crystal surface-emitting laser unit 100e of the photonic crystal surface-emitting laser element 200e of the present embodiment, the diffraction grating 300 is disposed on one side of the doped semiconductor layer 110, and in the example of FIG. 5, The substrate 160 is disposed between the doped semiconductor layer 110 and the diffraction grating 300 . In this embodiment, the diffraction grating 300 can be a part of the first electrode 140 , that is, the center of the first electrode 140 has the strip-shaped slits 142 arranged periodically to form the diffraction grating 300 . Alternatively, in other embodiments, the material of the diffraction grating 300 may also be other metals, semiconductors or oxides different from the first electrode 140, and the first electrode 140 has an opening in the center, and the diffraction grating 300 is disposed in this opening .

On the other hand, in this embodiment, the second electrode 150 e covers the photonic crystal layer 130 , and the light beam 122 emits light toward the bottom of FIG. 5 .

FIG. 6 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Please refer to FIG. 6 , the photonic crystal surface-emitting laser device 200f of this embodiment is similar to the photonic crystal surface-emitting laser device 200e in FIG. 5 , and the differences between the two are as follows. In the photonic crystal surface-emitting laser unit 100f of the photonic crystal surface-emitting laser element 200f of this embodiment, the doped semiconductor layer 110 and the first electrode 140 are disposed on the same side of the substrate 160, and the diffraction grating 300 The first electrode 140 is respectively disposed on opposite sides of the substrate 160 .

FIG. 7 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Please refer to FIG. 7 , the photonic crystal surface-emitting laser device 200 g of this embodiment is similar to the photonic crystal surface-emitting laser device 200 e in FIG. 5 , and the differences between the two are as follows. In the photonic crystal surface-emitting laser unit 100g of the photonic crystal surface-emitting laser element 200g of the present embodiment, the surface of the substrate 160g facing away from the light-emitting layer 120 has a diffraction grating surface structure 162g to form a diffraction grating 300g .

FIG. 8 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Please refer to FIG. 8 , the photonic crystal surface-emitting laser device 200 h of this embodiment is similar to the photonic crystal surface-emitting laser device 200 f in FIG. 6 , and the differences between the two are as follows. In the photonic crystal surface-emitting laser unit 100h of the photonic crystal surface-emitting laser element 200h of this embodiment, the surface of the substrate 160h facing away from the light-emitting layer 120 has a diffraction grating surface structure 162h to form a diffraction grating 300h .

FIG. 9 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Referring to FIG. 9 , the photonic crystal surface-emitting laser device 200 j of this embodiment is similar to the photonic crystal surface-emitting laser device 200 shown in FIG. 1C , and the differences between the two are as follows. In the photonic crystal surface-emitting laser unit 100j of the photonic crystal surface-emitting laser device 200j of this embodiment, the cladding layer 132j has a photonic crystal structure and is covered with a semiconductor layer 132'. The material of the semiconductor layer 132' is similar or identical to that of the cladding layer 132j, and can be a P-type or N-type doped semiconductor layer along with the cladding layer 132j. A graded index layer 136j and an ohmic contact layer 134j may be sequentially disposed on the semiconductor layer 132'. The current confinement layer 180 covers the edges of the semiconductor layer 132' and the ohmic contact layer 134j, and its opening 182 exposes the center of the ohmic contact layer 134j. The second electrode 150 is connected to the ohmic contact layer 134j through the opening 182, and the diffraction grating 300 is located at the center of the ohmic contact layer 134j.

FIG. 10 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Please refer to FIG. 10, the photonic crystal surface-emitting laser element 200k of this embodiment is similar to the photonic crystal surface-emitting laser element 200e in FIG. 5 and the photonic crystal surface-emitting laser element 200j in FIG. 9, and the differences are as follows mentioned. In the photonic crystal surface-emitting laser unit 100k of the photonic crystal surface-emitting laser element 200k of this embodiment, the coating layer 132j, the semiconductor layer 132', the graded refractive index layer 136j and the ohmic contact layer shown in FIG. 5 instead of the photonic crystal layer 130 in FIG. 5 , and the photonic crystal surface-emitting laser unit 100k does not include the transparent conductive layer 170 , and the second electrode 150k is connected to the ohmic contact layer 134j through the opening 182 .

FIG. 11 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Please refer to FIG. 11 , the photonic crystal surface-emitting laser device 200m of this embodiment is similar to the photonic crystal surface-emitting laser device 200k in FIG. 10 , and the differences between the two are as follows. The photonic crystal surface-emitting laser unit 100m of the photonic crystal surface-emitting laser device 200m of this embodiment further includes a distributed Bragg reflector 195 disposed between the semiconductor layer 132' and the graded-index layer 136j.

In other embodiments, the photonic crystal layer 130 in FIG. 6, FIG. 7, and FIG. layer 136j, ohmic contact layer 134j, and second electrode 150k, and does not have a transparent conductive layer 170, that is, the structure above the light-emitting layer 120 in FIG. 6, FIG. 7, and FIG. 8 can be replaced with the light-emitting layer in FIG. The structure of more than 120 can be used to form another 6 kinds of photonic crystal surface-emitting laser units.

FIG. 12 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. Please refer to FIG. 12 , the photonic crystal surface-emitting laser device 200i of this embodiment is similar to the photonic crystal surface-emitting laser device 200 shown in FIG. 1A , and the differences between the two are as follows. The photonic crystal surface-emitting laser element 200i of this embodiment includes a plurality of photonic crystal surface-emitting laser units 100 arranged in an array. In FIG. 12, 2×2 photonic crystal surface-emitting laser units 100 are taken as an example. However, in other embodiments, there may be M×N photonic crystal surface-emitting laser units 100 , where M and N are any positive integers. For example, in one embodiment, the photonic crystal surface-emitting laser device 200 i may include 10×10 photonic crystal surface-emitting laser units 100 . At least one of the period and the arrangement direction of the plurality of diffraction gratings 300 of these photonic crystal surface-emitting laser units 100 is different. For example, the period or arrangement direction (ie period direction) of the diffraction gratings 3001, 3002, 3003 and 3004 in FIG. Different light emitting directions of the light beam 122 are formed.

In this embodiment, the photonic crystal surface-emitting laser units 100 are electrically connected to a controller 210 , and the controller 210 can individually and independently control the light emission of the photonic crystal surface-emitting laser units 100 . For example, since these photonic crystal surface-emitting laser units 100 have different light emitting directions, the controller 210 can sequentially make these photonic crystal surface-emitting laser units 100 emit beams 122 (ie, laser beams) in different directions, In order to achieve the effect of beam scanning. Since such light beam scanning is electronically controlled instead of mechanically controlled, it has faster scanning speed, higher reliability and better durability. Such a photonic crystal surface-emitting laser device 200i can be applied to light detection and ranging, such as lidar or three-dimensional sensing, and has the advantages of high speed, good reliability, and high durability. In addition, this kind of laser (photonic crystal surface-emitting laser device 200i) that does not rely on mechanical action, high power, high beam quality and can achieve two-dimensional scanning can also be applied to the sensing system of smart mobility , object recognition systems or adaptive lighting, etc.

In this embodiment, the controller 210 can be designed by using Hardware Description Languages (Hardware Description Languages, HDL) or any other design method of digital circuits and analog circuits familiar to those skilled in the art, and the hardware circuit can be Programmable gate array (Field Programmable Gate Array, FPGA), complex programmable logic device (Complex Programmable Logic Device, CPLD) or application-specific integrated circuit (Application-Specific Integrated Circuit, ASIC).

In addition, the photonic crystal surface-emitting laser unit 100 in the photonic crystal surface-emitting laser element 200i can also use the photonic crystal surface-emitting laser unit of other embodiments above (such as the photonic crystal surface-emitting laser unit 100a ~100h) to form various photonic crystal surface-emitting laser elements with arrayed photonic crystal surface-emitting laser units.

To sum up, in the photonic crystal surface-emitting laser element of the embodiment of the present invention, since the diffraction grating configured on the photonic crystal layer or the doped semiconductor layer is used to diffract the light diffracted by the photonic crystal layer Therefore, a simple structure can be used to determine the deflection direction of the laser beam. The photonic crystal surface-emitting laser device of an embodiment of the present invention may include a plurality of photonic crystal surface-emitting laser units arranged in an array, and the periods of the multiple diffraction gratings of these photonic crystal surface-emitting laser units are in accordance with the At least one of the arrangement directions is different. Since the photonic crystal surface-emitting laser units emit light in different directions, the controller can sequentially make the photonic crystal surface-emitting laser units emit laser beams in different directions to achieve the effect of beam scanning. Since such light beam scanning is electronically controlled instead of mechanically controlled, it has faster scanning speed, higher reliability and better durability. Such a photonic crystal surface-emitting laser device can be applied to light detection and ranging, such as lidar or three-dimensional sensing, and has the advantages of high speed, good reliability, and high durability.

100, 100a, 100c, 100d, 100e, 100f, 100g, 100h, 100j, 100k, 100m: photonic crystal surface-emitting laser unit 110: doped semiconductor layer 120: luminous layer 122: Beam 130: photonic crystal layer 131: Through hole 132, 132j: cladding layer 132': semiconductor layer 134, 134j: ohmic contact layer 136, 136j, 190: graded refractive index layer 140: first electrode 142, 152: long strip slits 150, 150e, 150k: the second electrode 160, 160g, 160h: Substrate 162g, 162h: Diffraction grating surface structure 170, 170a: transparent conductive layer 172a: Diffraction grating surface 180: current limiting layer 182: opening 195: Distributed Bragg reflector 200, 200a, 200c, 200d, 200e, 200f, 200g, 200h, 200i, 200j, 200k, 200m: photonic crystal surface-emitting laser components 210: controller 300, 300g, 300h, 3001, 3002, 3003, 3004: Diffraction grating P1: periodic direction

FIG. 1A is a perspective view of a photonic crystal surface-emitting laser device according to an embodiment of the present invention. FIG. 1B is a schematic top view of the photonic crystal surface-emitting laser device in FIG. 1A . FIG. 1C is a schematic cross-sectional view of the photonic crystal surface-emitting laser device in FIG. 1B along line I-I. FIG. 1D and FIG. 1E are schematic top views of photonic crystal surface-emitting laser devices according to two other embodiments of the present invention. FIG. 2A is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 2B is a simplified perspective view of the photonic crystal layer, the diffraction grating surface of the transparent conductive layer, and the diffraction grating in FIG. 2A . FIG. 3 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 4 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 5 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 6 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 7 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 8 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 9 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 10 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 11 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention. FIG. 12 is a schematic cross-sectional view of a photonic crystal surface-emitting laser device according to another embodiment of the present invention.

100: Photonic crystal surface-emitting laser unit 110: doped semiconductor layer 120: luminous layer 122: Beam 130: photonic crystal layer 131: Through hole 132: cladding layer 134: Ohmic contact layer 136, 190: Refractive index gradient layer 140: first electrode 150: second electrode 152: Long strip slit 160: Substrate 170: transparent conductive layer 180: current limiting layer 182: opening 200: Photonic crystal surface-emitting laser components 300: Diffraction grating

Claims (9)

A photonic crystal surface-emitting laser element, including: at least one photonic crystal surface-emitting laser unit, the photonic crystal surface-emitting laser unit includes: a light-emitting layer for emitting a light beam; a photonic crystal layer configured On one side of the light-emitting layer; a doped semiconductor layer configured on the other side of the light-emitting layer; and a diffraction grating configured on the photonic crystal layer or the doped semiconductor layer; and a first electrode , electrically connected to the doped semiconductor layer, wherein the photonic crystal surface-emitting laser unit further includes a second electrode disposed on the photonic crystal layer and electrically connected to the photonic crystal layer. The photonic crystal surface-emitting laser device as claimed in claim 1, wherein a part of the second electrode is the diffraction grating, and the light beam is diffracted by the photonic crystal layer and the diffraction grating, and is emitted from the photonic crystal A surface-firing laser unit emits light. The photonic crystal surface-emitting laser device as claimed in claim 1, wherein the photonic crystal surface-emitting laser unit further includes a transparent conductive layer disposed between the photonic crystal layer and the second electrode. The photonic crystal surface-emitting laser device as claimed in claim 3, wherein the surface of the transparent conductive layer facing away from the light-emitting layer is a diffraction grating surface. The photonic crystal surface-emitting laser device as claimed in claim 1 further includes a substrate disposed between the doped semiconductor layer and the first electrode. The photonic crystal surface-emitting laser device according to claim 1 further includes a substrate, wherein the doped semiconductor layer and the first electrode are disposed on the same side of the substrate. The photonic crystal surface-emitting laser device as claimed in Claim 1 further includes a substrate disposed between the doped semiconductor layer and the diffraction grating. The photonic crystal surface-emitting laser device as claimed in Claim 1 further includes a substrate, wherein the doped semiconductor layer is disposed between the light-emitting layer and the substrate, and the surface of the substrate facing away from the light-emitting layer has A diffraction grating surface structure to form the diffraction grating. The photonic crystal surface-emitting laser device as described in claim 1, wherein the at least one photonic crystal surface-emitting laser unit is a plurality of photonic crystal surface-emitting laser units arranged in an array, and the photonic crystal surface-emitting laser units The periods of the plurality of diffraction gratings of the type laser unit are different from at least one of the arrangement directions.

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