1882results about "Optical wave guidance" patented technology

Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.

The invention relates to the technical field of semiconductor lasers, in particular to a laser based on a bimetallic Bragg grating and a top surface HR reflecting film, which comprises a gain chip, a first high-reflection HR film is plated on the left end surface of the gain chip, and a first anti-reflection AR film is plated on the right end surface of the gain chip. A metal Bragg grating waveguide is arranged on the right side of the gain chip, the right end face of the gain chip and the left end face of the metal Bragg grating waveguide are aligned and attached to form an outer cavity structure, and the left end face of the metal Bragg grating waveguide is plated with a second anti-reflection AR film. The right end face of the metal Bragg grating waveguide is plated with a third anti-reflection AR film. Performance test is carried out on the laser provided by the invention, and test results show that the line width is 0.6 kHz, the SMSR is 63dB, and the threshold current is 22mA, thereby verifying the effectiveness of the laser provided by the invention.

Electro-absorption modulators (EAM) and monolithically integrated electro-absorption modulated lasers (EML) and methods of fabrication are disclosed. Vertically stacked waveguides for a distributed feedback (DFB) laser, an electro-absorption modulator (EAM) and a passive output waveguide are vertically integrated, and the DFB laser, EAM and output waveguide are optically coupled using laterally tapered vertical optical couplers. Laterally tapered vertical optical couplers provides an alternative to conventional butt-coupling of a laser and EAM, offering improved reliability for high power operation over extended lifetimes. Optionally, the EML comprises monolithically integrated electronic circuitry, e.g., driver and control electronics for the DFB laser and EAM. Beneficially, integrated EAM driver and control circuitry comprises a high-speed electro-optical control loop for very high-speed linearization and temperature compensation, e.g. to enable advanced modulation schemes, such as PAM-4 and DP-QPSK, for analog optical data center interconnect applications. Some embodiments are compatible with fabrication using a single epitaxial growth.

Embodiments of the present application relate to the technical field of semiconductor lasers, and provide a semiconductor laser and a manufacturing method therefor, which are used to mitigate the problem of chirp in semiconductor lasers. The semiconductor laser comprises: a substrate; a ridge waveguide which is arranged on the substrate and extends in a first direction of the substrate; and a grating which is arranged at a top portion of the ridge waveguide. The grating comprises first regions and second regions periodically arranged in the first direction, each first region comprises a semiconductor material, each second region comprises an insulating dielectric material, and the refractive index of the insulating dielectric material is greater than the refractive index of the semiconductor material.

The invention relates to the technical field of semiconductor lasers, in particular to a laser based on a bimetallic Bragg grating and a top SiO2 waveguide layer, which comprises a gain chip, the left end face of the gain chip is plated with a first high-reflection HR film, and the right end face of the gain chip is plated with a first anti-reflection AR film; a metal Bragg grating waveguide is arranged on the right side of the gain chip, the right end face of the gain chip and the left end face of the metal Bragg grating waveguide are aligned and attached to form an outer cavity structure, and the left end face of the metal Bragg grating waveguide is plated with a second anti-reflection AR film. The right end face of the metal Bragg grating waveguide is plated with a third anti-reflection AR film. According to the invention, a temperature change test is carried out, and the wavelength drift is controlled to be + / -0.002 nm in a range of-40 DEG C to 85 DEG C; performance test results show that the line width is 0.6 kHz, the SMSR is 65 dB, and the threshold current is 22 mA.

A distributed feedback (DFB) laser includes a planar substrate; a laser section; and a mirror section optically coupled to said laser section. The laser section includes a front facet, an active layer substantially parallel to the planar substrate but not coplanar with the planar substrate and configured to emit light through the front facet, and a first Bragg grating arranged in a planar layer substantially parallel to the active layer but not coplanar with the active layer and on a side of the active layer opposite to the planar substrate. The mirror section is optically coupled to the laser section, and includes a second Bragg grating configured to reflect light towards the front facet. The second Bragg grating is arranged in a planar layer that is coplanar with the active layer.

The invention discloses a distributed feedback laser and a preparation method thereof, and relates to the field of lasers. The preparation method of the distributed feedback laser comprises the following steps: forming a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer, an upper limiting layer, a grating layer, a grating buried layer, a corrosion stop layer, an InP cladding, a barrier gradient layer, a contact layer and a sacrificial layer on a substrate, wherein the sacrificial layer comprises an InP layer and an InGaAs layer which are stacked in sequence; etching to form a ridge waveguide structure; forming an insulating layer; removing the insulating layer in a preset area on the ridge waveguide structure to expose the sacrificial layer; wherein the side wall of the InGaAs layer is completely exposed, and the side wall of the InP layer is partially exposed; and etching to remove the InGaAs layer and the InP layer to form an upper electrode layer and a lower electrode layer. According to the invention, the reliability and the electro-optical conversion efficiency of the distributed feedback laser can be improved.

The invention provides a surface grating surface emitting laser. The surface grating surface emitting laser comprises an N-face metal electrode layer; an N-face waveguide layer, an active layer, a P-face waveguide layer and a ridge waveguide layer are sequentially stacked on the N-face metal electrode layer, wherein the ridge waveguide layer comprises a gain region and a loss region; the P-surface metal electrode layer is arranged on the gain region of the ridge waveguide layer; and the P-surface silicon dioxide layer is arranged on the loss region of the ridge waveguide layer. According to the laser, through the characteristic that mode fields are distributed in a loss area and a gain area after PT symmetric breaking, a light field achieves surface light emitting through vertical diffraction coupling of surface gratings of the loss area, and the laser is different from a common laser structure in which gratings are completely etched in the longitudinal direction and electrodes are manufactured on the two sides. The mode gain difference is symmetrically manufactured through PT, double lobes are eliminated, a single mode is stabilized, lambda / 4 phase shift does not need to be introduced, and the process difficulty is reduced.

A vertical-cavity surface-emitting laser (VCSEL) may include a distributed Bragg reflector (DBR) stack. The DBR stack may include a mirror structure over a cavity region. The DBR stack may include an etch stop layer over the mirror structure. The DBR stack may include a grating layer over the etch stop layer. The grating layer may include a grating structure associated with polarization of output light emitted by the VCSEL.

The invention relates to the technical field of semiconductor lasers, in particular to a DFB laser based on a top metal grating, and the DFB laser comprises a gain chip, the left end face of the gain chip is plated with a high-reflection HR film, and the right end face of the gain chip is plated with an anti-reflection AR film; the upper end face of the gain chip is provided with a ridge optical waveguide, and the upper end face of the ridge optical waveguide is provided with a metal Bragg reflection grating layer. A self-heterodyne interference method (the line width of a local oscillator is smaller than 500 Hz) is adopted, and the measured value of the 3dB line width is 50 Hz (the measured value of a traditional DFB is 125 kHz). The mode purity degree is verified through a Lorenzian fitting broadening factor 1.15; the wavelength drift is less than 0.05 pm / DEG C within the range of-40 DEG C to 85 DEG C after compensation of the temperature compensation circuit. The temperature tuning coefficient is 0.08 pm / DEG C, the current tuning coefficient is 0.05 pm / mA, and the tuning coverage range is 1530-1545 nm.

The invention relates to the technical field of semiconductors, and discloses an edge-emitting semiconductor laser and a preparation method thereof, and the preparation method comprises the steps: forming a current injection region and a passivation layer at the side part of the current injection region on the surface of one side, opposite to an upper limiting layer, of a P-surface contact layer of a laser wafer; the laser wafer is divided into a plurality of laser chips in the vertical direction through a plurality of first cleavage channels and a plurality of second cleavage channels; forming a first P-type metal layer on the surface of the laser chip, the surface of the first cleavage channel and the surface of the first region of the second cleavage channel; forming a second P-type metal layer on the surface of one side of the first P-type metal layer of the laser chip through an electroplating process; the first P-type metal layer in the first region is used for communicating the surfaces of the plurality of laser chips; the laser wafer is cleaved into a plurality of edge-emitting semiconductor lasers. Compared with the prior art, the reliability and the yield of the edge-emitting high-power laser can be improved, and the cost of a preparation process is reduced.

Provided is a semiconductor laser and a display device thereof. The semiconductor laser includes a first semiconductor layer, a second semiconductor layer, and an active layer located therebetween; a first waveguide layer is disposed between the first semiconductor layer and the active layer, and a second waveguide layer is disposed between the second semiconductor layer and the active layer; an electron blocking layer is disposed between the second waveguide layer and the second semiconductor layer; the electron blocking layer includes at least a part of a P-type doped layer on a side close to the second semiconductor layer, in which a composition of the P-type doped layer is greater than 1E19−3; and a P-type doping concentration of the side of the electron blocking layer close to the second semiconductor layer is higher than a P-type doping concentration of the electron blocking layer away from the second semiconductor layer.

A semiconductor optical amplifier (SOA) with a variable optical confinement factor I′ along the length of the device is disclosed. At the input end of the SOA, the optical confinement is high as an optical core is adjacent an optical gain layer, resulting in a high-gain region that rapidly increases the optical signal power. In the central portion of the SOA, the optical confinement is continuously reduced as the optical core is tapered away from the optical gain layer, thereby lowering the gain, but increasing the output saturation power. Near the output end of the SOA, the optical confinement factor is held constant, providing a length of additional gain, thereby further increasing the output power. The SOA may optionally include a spot-size converter region to focus the output optical signal.

The invention relates to the technical field of semiconductor lasers, in particular to a semiconductor laser chip which comprises a substrate, a growth buffer layer, a lower waveguide layer, an active layer, an upper waveguide layer, an upper cladding and a cover layer which are sequentially stacked from bottom to top in the longitudinal direction. A plurality of current injection regions with different widths and a plurality of ion injection regions with different widths are arranged in the transverse direction of the semiconductor laser chip; a plurality of current injection regions are distributed between the two ion injection regions on the two sides; the ion implantation region penetrates through the cover layer and a part of the upper cladding layer in the longitudinal direction; forming a ridge waveguide structure on the cover layer; processing the ridge waveguide structure through ion implantation to form a lateral chirp electric injection modulation ridge waveguide structure; the chirp electric injection structure formed by the invention can regulate and control each order mode from the aspects of gain and loss, so that the loss of a high-order mode is greater than that of a fundamental mode, and finally, the effects of reducing the output of the high-order mode, reducing the divergence angle and improving the beam quality of a far field are achieved.

The invention provides a quantum well, a multi-quantum well epitaxial structure and a preparation method thereof, and belongs to the field of semiconductor lasers. The invention provides a quantum well which is of a multi-layer structure and comprises alternate quantum barrier layers and quantum well layers. The array substrate further comprises a gradient buffer layer. The adjacent quantum barrier layer and quantum well layer are combined through a gradient buffer layer; the bottom layer and the top layer in the multi-layer structure are quantum barrier layers; in a unit formed by the connected quantum barrier layer, gradual change buffer layer and quantum well layer, with the quantum barrier layer as the beginning and the adjacent quantum well layer as the end, the size of the gradual change buffer layer in the horizontal direction is gradually reduced, the emission wavelength of the gradual change buffer layer is gradually increased in the direction from beginning to end, and the emission wavelength of the gradual change buffer layer is gradually increased. The initial emission wavelength of the gradient buffer layer is consistent with the emission wavelength of the quantum barrier, and the final emission wavelength of the gradient buffer layer is smaller than the emission wavelength of the quantum well. The quantum well has a high carrier migration rate, a high refractive index and a high optical confinement factor.

The invention provides a patterned photonic crystal laser and a preparation method thereof, the laser comprises a substrate, and a first mask layer, a photonic crystal layer and a second mask layer which are sequentially deposited on the substrate, a light emitting area is etched in the central area of the second mask layer, and transparent conductive layers are deposited on the surface of the second mask layer and the light emitting area; a p-annular electrode is arranged on the surface of the transparent conductive layer on the second mask layer, and an n-annular electrode is arranged below the substrate; the photonic crystal layer is composed of a nanorod array and a polymer filled in gaps of nanorods; holes distributed in a patterned array are etched in the surface of the first mask layer, and nanorods are epitaxially grown in hole areas; the nanorod is formed by sequentially depositing a substrate contact layer, a first waveguide layer, a multi-quantum well layer, a second waveguide layer, a coating layer and a component gradient layer. According to the invention, through collaborative design optimization of all the layers, emission of laser with specific wavelength and preparation of a laser emitting laser with single longitudinal mode, narrow linewidth and stable wavelength are realized.

The invention discloses a low-divergence-angle narrow-linewidth high-power semiconductor laser. Relates to the technical field of semiconductor lasers, in particular to a low-divergence-angle narrow-linewidth high-power semiconductor laser. According to the invention, the parabolic waveguide structure is etched in the light field expansion area, and the metal reflector is introduced to realize a novel light field expansion and metal reflector integrated structure, and the transverse divergence angle of a laser mode is reduced through the expansion structure at the tail end of the waveguide. The laser comprises a laser gain area, a light field expansion area and a spectrum purification area at the tail of the light field expansion area. The laser gain region, the light field expansion region and the spectrum purification region at the tail part of the light field expansion region are made of the same laser epitaxial material in the longitudinal direction, the laser gain region is adjacent to the light field expansion region along the horizontal light emitting direction, and the light field expansion region is adjacent to the spectrum purification region at the tail part of the light field expansion region along the horizontal light emitting direction; the longitudinal direction is the direction from the substrate to the contact layer.

The invention provides an EML laser and a preparation method of an air bridge, belongs to the technical field of optical communication lasers, and is used for solving the problem that the stray capacitance of connecting metal between a waveguide electrode and a PAD electrode of the EML laser is too large. The preparation method of the air bridge process of the EML comprises the following steps: growing a mask layer on the surface of an epitaxial InP wafer, photoetching to form a ridge waveguide pattern, etching the mask layer by adopting ICP (Inductively Coupled Plasma), and removing photoresist; etching the ohmic contact layer by adopting ICP (Inductively Coupled Plasma) and removing the mask layer; gluing and photoetching the surface of the wafer to form a pier pattern; adopting ICPCVD to grow a dielectric film at low temperature; gluing and photoetching the surface of the wafer to form a dielectric film bridge pattern; carrying out ICP etching on the dielectric film and removing the bridge and pier photoresist to form a dielectric film bridge; and performing wet etching on the InP epitaxial layer to the etching stop layer. According to the method, the dielectric film bridge is built at the connecting metal between the waveguide electrode and the PAD electrode, the low dielectric constant characteristic of air is utilized, the distance between the metal and the quantum well is greatly increased, the stray capacitance of the EML is reduced, and the bandwidth is improved.

Disclosed is a semiconductor laser, from bottom to top, comprising: a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper limiting layer. The lower limiting layer is composed of at least one of AllnGaN, AllnN, AlGaN, InN, AlN, InGaN, and GaN. A thickness of the lower limiting layer is denoted as x, and 10 angstroms≤x≤90,000 angstroms. The lower limiting layer includes a first lower limiting layer, a second lower limiting layer, and a third lower limiting layer. The lower limiting layer forms an electron saving structure and a stress regulating structure to regulate a carrier distribution and a stress distribution of the active layer, thereby reducing a threshold current and improving a slope efficiency of the laser.

The invention discloses a butt-joint epitaxial growth ridge waveguide laser chip and a manufacturing method thereof, and belongs to the technical field of lasers, and the manufacturing method comprises the following steps: manufacturing a ridge waveguide structure on an epitaxial wafer subjected to butt-joint growth, coating a layer of photoresist adhesive and two layers of photoresist on the ridge waveguide structure, forming a window at a convex ridge of the overlay ridge waveguide structure, and forming the butt-joint epitaxial growth ridge waveguide laser chip. The window covers an area above the passive area and a part of the active area, exposing and developing the epitaxial wafer in the window, removing a part of photoresist, etching and removing the residual photoresist in the window to expose the ohmic contact layer, corroding and removing the ohmic contact layer in the window, and removing all the photoresist on the surface of the epitaxial wafer. The length of the ohmic contact layer is controlled through double-layer adhesive photoetching and wet etching, and the ohmic contact layer above the active region is further etched, so that diffusion of current to the passive waveguide direction is effectively inhibited, the threshold current of the chip is reduced, the heating value of the passive waveguide region is reduced, and the reliability of the chip is improved.

A method of fabricating an optoelectronic component, performed on a multi-layered wafer disposed on a substrate. The method comprises the steps of: etching the multi-layered wafer, thereby defining a slab and a multi-layered ridge, the slab having an upper surface below the ridge and being located between the multi-layered ridge and the substrate; selectively epitaxially growing a III-V semiconductor cladding adjacent to a first and second sidewall of the ridge, the cladding layer extending from the upper surface of the slab along the first and second sidewalls, and thereby cladding an optically active waveguide within the multi-layered ridge; and providing a first and second electrical contact, which electrically connect to a layer of the multi-layered ridge and the slab respectively.

The embodiment of the invention provides a laser array and a laser radar, and relates to the technical field of optical perception. The differential resistance of the laser array is adjustable, and the optical power of the output emitted laser is adjustable. The laser array comprises a first laser and a second laser; the first laser comprises a first reflecting layer, a first active layer and a second reflecting layer which are sequentially arranged along the epitaxial direction, and a first oxidation hole is formed in the second reflecting layer; the second laser comprises a third reflecting layer, a second active layer and a fourth reflecting layer which are sequentially arranged in the epitaxial direction, a second oxidation hole is formed in the fourth reflecting layer, and a light blocking layer is further arranged on the side, away from the second active layer, of the fourth reflecting layer. The projection of the light blocking layer on the second active layer is overlapped with the projection of the second oxidation hole on the second active layer; the first laser is electrically connected with the second laser.

High-power, integrated optical amplifiers are described in which gain waveguides of the amplifiers are designed to improve power performance by reducing power saturation effects in the amplifier. The gain waveguides can change, in at least one aspect, along the length of the gain waveguide to reduce gain saturation. Multi-mode optical beams and / or multi-stage amplification can also be employed to reduce gain saturation.

The invention relates to the technical field of semiconductor lasers, in particular to an ultra-narrow linewidth wavelength-adjustable external cavity laser based on a planar metal grating, which comprises a gain chip, and the left end face and the right end face of the gain chip are respectively plated with a high reflection film and a first antireflection film; a planar metal grating waveguide is arranged on the right side of the gain chip, the right end face of the gain chip is aligned and attached to the left end face of the planar metal grating waveguide, and a second antireflection film and a third antireflection film are plated on the left end face and the right end face of the planar metal grating waveguide respectively; the planar metal grating waveguide comprises a grating waveguide substrate, a ridge optical waveguide is arranged on the upper portion of the grating waveguide substrate, an annular resonance optical waveguide is arranged on the front side of the ridge optical waveguide, a planar metal grating is arranged on the upper portion of the ridge optical waveguide, and a top covering layer is arranged on the upper portion of the planar metal grating. Through the centimeter-level metal grating and the low-loss coupling structure, light beam quality with 3dB line width less than 700Hz and M2 less than 0.9 is realized.

The invention relates to the technical field of semiconductors, and discloses a photonic crystal edge-emitting laser and a preparation method thereof, and the preparation method comprises the steps: providing a laser substrate which sequentially comprises a substrate, an N-type coating layer, an N-type waveguide layer, an active layer, a P-type waveguide layer, a P-type coating layer and a P-type cover layer from bottom to top; the laser base body comprises a rectangular third target area, second target areas at the two ends of the length direction of the third target area and first target areas located on the side portions of the third target area and the second target areas in the vertical direction; forming an ion implantation region in the first target region; photonic crystals are formed in the first target area and the second target area; the first target area forms a mode filtering area, the second target area forms a current limiting area, and the third target area forms a current injection area. Compared with the prior art, the heat dissipation characteristic of the laser in the transverse direction can be enhanced, the electrical performance and reliability of the laser are improved, and meanwhile the technological process is simplified.

Semiconductor light-emitting apparatus includes substrate, submount above substrate, and semiconductor laser above submount. Semiconductor laser and submount are bonded to each other with first bonding material. Substrate and submount are bonded to each other with second bonding material. Submount has first region and second region near substrate, first region being a region on which spacer is disposed, and second region being a region without spacer. Submount is bonded to substrate by covering at least a portion of second region with second bonding material.

The invention provides a semiconductor laser chip and a preparation method, and belongs to the technical field of semiconductor laser chip preparation, and the semiconductor laser chip comprises an N-surface metal, a substrate, an N-type limiting layer, an N-type waveguide layer, a tensile strain quantum well, a P-type waveguide layer, a P-type limiting layer, an ohmic contact layer, a SiO2 insulating layer, a first P-surface metal layer and a second P-surface metal layer which are sequentially arranged from bottom to top. Waveguide grooves are symmetrically formed in the two sides of the ohmic contact layer and penetrate through the ohmic contact layer, the bottoms of the grooves sink to the P-type limiting layer but do not exceed the P-type limiting layer, and a ridge waveguide is formed between the two grooves. The depth of the waveguide groove is of a stepped structure in the longitudinal direction, the depth of the area close to the cavity surface is increased to the N-type waveguide layer, the area completely covers the SiO2 insulating layer and the first layer of P-surface metal, but no second layer of P-surface metal exists, and the longitudinal stepped structure is formed. Through the design of the tensile strain quantum well and the stepped waveguide groove, cavity surface tensile strain release is realized, light absorption is reduced, and the reliability and the service life of the chip are improved.

The utility model relates to the technical field of lasers, and discloses a high-slope-efficiency surface grating surface emitting laser which comprises a substrate, a lower waveguide layer, an active layer and an upper waveguide layer from bottom to top along the cross section. A ridge-shaped waveguide is formed in the middle area of the uppermost layer of the upper waveguide layer, and a Bragg grating is etched on the surface of the ridge-shaped waveguide; the Bragg grating comprises a section of second-order grating located in the middle and two sections of first-order gratings located at the two ends; a lambda / 4 phase shift is arranged in the second-order grating; the lambda / 4 phase shift is located in an etching area or a non-etching area of the first-order grating closest to the second-order grating; when the lambda / 4 phase shift is located in the etching region of the first-order grating closest to the second-order grating, the upward diffraction light power of the second-order grating is maximum, and the downward diffraction light power is minimum; when the lambda / 4 phase shift is located in the non-etching area of the first-order grating closest to the second-order grating, the upward diffraction light power of the second-order grating is minimum, and the downward diffraction light power of the second-order grating is maximum. According to the invention, high-slope efficiency lasing can be realized.

The invention discloses a high-reliability DFB laser and a preparation method thereof, and relates to the field of lasers. The DFB laser comprises a substrate, a bottom electrode, a first epitaxial layer, a second epitaxial layer, a passivation layer, a top electrode and a dielectric film. The second epitaxial layer comprises a body part and at least one ridge waveguide structure, and an isolation groove for exposing the first epitaxial layer is arranged between the body part and the ridge waveguide structure; the passivation layer covers the surface of the body part, the surface and the side wall of the ridge waveguide structure and the side wall and the bottom wall of the isolation groove; the top electrode covers the ridge waveguide structure and the side wall and the bottom wall of the isolation groove, and at least partially extends to the surface of the body part; the dielectric film covers the ridge waveguide structure; the top surface of the dielectric film is higher than the top surface of the top electrode, and the hardness of the dielectric film is greater than that of the top electrode. According to the invention, the yield of the DFB laser can be improved, and the reliability of the DFB laser can be improved.

To provide a laser diode chip capable of emitting RGB light with one chip and also capable of obtaining high emission efficiency even when a chip is miniaturized.SOLUTION: A laser diode chip has, on an n-type AlxGa1-xN layer (0≤x≤1), AlGaInN laser diode structures (B', G', R') emitting blue light, green light and red light, respectively. These laser diode structures have: an insulating film (703) having at least one rectangular opening (703a) on the n-type AlxGa1-xN layer; a polygonal truncated pyramid-shaped n-type AlyGa1-yN layer (0≤y≤1) (704) on the n-type AlxGa1-xN layer in a portion of the opening; active layers (705-707) each provided along a top surface and a side surface of the n-type AlyGa1-yN layer; p-type AlzGa1-zN layers (0≤z≤1) (708-710) covering each active layer; a p-side electrode (711) on the p-type AlzGa1-zN layers; and an n-side electrode (712) provided on the n-type AlxGa1-xN layer or a rear face thereof.SELECTED DRAWING: Figure 37B