1806 results about "Contact layer" patented technology

The present application relates to a solar cell, a method for manufacturing the same, a photovoltaic module and a photovoltaic system. The solar cell includes: a substrate (110), including a first surface (S1) and a second surface (S2) being opposite to each other, wherein the first surface (S1) has a first region (A) and a second region (B) adjacent to each other in a first direction; a passivating contact layer (120), located in the first region (A) of the first surface (S1); a polysilicon layer (130) located on at least a part of a surface of the passivating contact layer (120) away from the substrate (110); the passivating contact layer (120) including a first tunneling layer (121) and a first doped layer (122), the first tunneling layer (121) and the first doped layer (122) being sequentially stacked on the first region (A) of the first surface (S1) of the substrate (110) in a direction away from the second surface (S2); and a first passivation layer (140), located on a surface of the polysilicon layer (130) away from the passivating contact layer (120) and on the second region (B) of the first surface (S1).

The invention discloses a method for improving the heat dissipation performance of an AlGaInP red light Micro LED chip. The method comprises the following steps: S1, preparing an epitaxial structure: processing a substrate and a buffer layer, growing an etching barrier layer and an ohmic contact layer, and carrying out stacking epitaxy on a functional layer; s2, patterning the silicon-based substrate: preparing a dielectric layer and a metal structure; s3, diamond ohmic contact layer integration: processing a p-type conductive diamond film layer, and carrying out metal reflection and bonding; s4, removing the substrate and forming an n-type structure: stripping the substrate to be in n-type contact; s5, back-end process integration: preparing an electrode and an optical structure; according to the invention, the heat dissipation performance of the chip is significantly improved; the series resistance is reduced by 30%-50%; the resistivity of the p / n type diamond ohmic contact layer is reduced by 1-2 orders of magnitude compared with ITO; gaAs material light absorption and metal shading are avoided, and the red light transmittance is improved from 75% to more than 90% by combining with the micro lens array; the method is compatible with existing MOCVD, CVD and photoetching processes, large-scale production of wafers of 2-12 inches can be achieved, and the manufacturing cost is reduced.

A semiconductor device includes a plurality of gate separated by an interlayer dielectric (ILD), a backside contact. The backside contact is extended below the plurality of gates and a dielectric layer, and from a first gate to a second gate of the plurality of gates, and a placeholder. The placeholder is extended below the plurality of gates and between the second gate and a third gate of the plurality of gates. The backside contact and the placeholder are not directly electrically connected.

A visual tactile sensor, a manipulator and a control method thereof, the visual tactile sensor comprising: a contact layer, at least a portion of which is transparent; when the contact layer is subjected to external force, at least one part of a plurality of markers in the marker array generates displacement and / or deformation; and the image acquisition unit is used for performing image acquisition on the marker array and performing image acquisition on the outside through the transparent part of the contact layer. The visual tactile sensor provided by the invention not only can capture the external visual information before operation to identify the operation object, but also can provide the tactile information in the operation process, so that the perception capability of an operation system is enhanced, and the operation success rate is improved.

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 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.

The embodiment of the invention relates to the photovoltaic field, and provides a back contact solar cell and a preparation method thereof, and a photovoltaic module, and the back contact solar cell comprises a substrate, and first doped regions and second doped regions which are arranged in a staggered manner; the first passivation contact layer is positioned in the first doped region; the second passivation contact layer is positioned in the second doped region; doped oxide layers, each doped oxide layer comprising a first portion and a second portion, the first portion being located on the surface of the first passivation contact layer; the second part is located on the second doped region; the connecting layer is located in a partial region of the first part, further surrounds a partial region of the second part and is electrically connected with the second passivation contact layer, and the connecting layer is located on the side face of the first passivation contact layer and is electrically connected with the first passivation contact layer. The back contact solar cell provided by the embodiment of the invention at least can improve the hot spot effect and increase the photoelectric conversion efficiency.

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 present application discloses a cell contact structure, a semiconductor device, and a method for fabricating the semiconductor device. The cell contact structure includes a contact layer positioned on a substrate and enclosed by a plurality of bit line structures and a plurality of partition layers; and a liner layer positioned between the contact layer and the substrate, between the contact layer and the plurality of bit line structures, and between the contact layer and the plurality of partition layers. A top surface of the contact layer and a top surface of the liner layer are substantially coplanar. The liner layer includes doped polycrystalline silicon, doped polycrystalline germanium, or doped polycrystalline silicon germanium. The contact layer includes tungsten, titanium, or titanium nitride.

Disclosed herein are embodiments of a wound treatment apparatus with electronic components integrated within a wound dressing. In some embodiments, a wound dressing apparatus can comprise a wound dressing. The wound dressing can comprise an absorbent material, an electronics unit comprising a negative pressure source, the electronics unit integrated within the wound dressing and at least partially encapsulated by a flexible film. The flexible film can comprise a window or aperture configured to permit fluid communication between the absorbent material and the negative pressure source. In some embodiments, a wound dressing apparatus can comprise a wound contact layer, an absorbent layer over the wound contact layer, the absorbent layer comprising one or more apertures, a cover layer configured to cover and form a seal over the wound contact layer and the absorbent layer, and an electronics assembly comprising a negative pressure source. A portion of the cover layer overlying the one or more apertures in the absorbent layer can be configured to be compressed within the aperture in the absorbent layer when negative pressure is applied to the wound dressing apparatus. The compressed cover layer can indicate a level of negative pressure below the cover layer. In some embodiments, the wound dressing apparatus can comprise an indicator material layer and a cover layer configured to cover and form a seal over the wound contact layer and the indicator material layer. The indicator material layer can be configured to protrude relative to a surrounding surface of an upper surface of the wound dressing apparatus when negative pressure is applied to the wound dressing apparatus and the protruding indicator material layer indicates a level of negative pressure below the cover layer.

The invention discloses a low-power-consumption photonic integrated device preparation method and a corresponding device, and relates to the technical field of semiconductor optoelectronic integrated devices.The device comprises a substrate, a cantilever beam type grating layer, two gain layers, two modulator layers, a wrapping layer and an electric contact layer, the two gain layers and the two modulator layers are symmetrically distributed, and the wrapping layer and the electric contact layer form a shallow ridge waveguide structure. The two symmetrically-distributed gain layers and the middle cantilever beam type grating layer jointly form a double-end resonant cavity structure, the structure shares a unified grating and a thermal tuning platform to achieve continuous, synchronous and high-precision control over cavity mode wavelengths, and balanced modulation and phase synchronization of double-end output are achieved in cooperation with the symmetrically-integrated high-speed modulator layers on the two sides. According to the technical scheme, the gain layer, the grating layer and the modulator layer are symmetrically integrated on the same substrate, the alignment error of a multi-cavity structure is reduced, synchronous scanning, low drift and strong anti-interference high-quality laser output can be obtained, meanwhile, efficient thermal tuning is conducted through the cantilever beam type grating layer, and power consumption is remarkably reduced.

The invention discloses an annealing temperature control method based on a differentiated ohmic contact material, and aims to solve the problems that the annealing temperature of an N-surface Au / Ge ohmic contact layer of an existing AlGaInP-based red light Micro-LED is not accurately monitored, a temperature field is not uniform and is difficult to detect, and abnormal response lags, the method comprises seven steps of processes (two times of patterning, two times of metal coating, two times of photoresist removal, annealing and observation), and the annealing temperature of the N-surface Au / Ge ohmic contact layer of the existing AlGaInP-based red light Micro-LED is controlled. Preparing a first Au / Ge ohmic contact layer (for function) and a second Au / Ge / Ni ohmic contact layer (for detection) on the N surface of the wafer; by means of the characteristic that Ni inhibits Au / Ge agglomeration, the two-layer agglomeration state difference is observed through an optical microscope, and the temperature is judged (in the normal state, the former agglomerates, and the latter does not agglomerate); the method is convenient in detection, supports batch detection, can find temperature abnormity in real time, improves the process stability, and is suitable for industrial mass production.

The invention belongs to the technical field of micromachining, and discloses a flexible micro needle tip array electrode based on composite multi-layer metal and a preparation method of the flexible micro needle tip array electrode. The flexible micro needle tip array electrode comprises a flexible substrate and a silicon micro needle tip array structure arranged on the flexible substrate, each silicon micro needle tip in the silicon micro needle tip array structure is provided with composite multilayer metal capable of conducting electricity and conducting signals, and the composite multilayer metal sequentially comprises a seed layer, a structural layer, an adhesion layer and a contact layer from inside to outside; the material of the seed layer is Cr, Ti, Ni, Mo, Ta, W, Fe, Cu, Au, Ag or Pt, the material of the structural layer is Cu, Ag or Au, the material of the adhesion layer is Cr, Ni, Ti, Mo, Ta or W, and the material of the contact layer is Au, Ag or AgCl. According to the invention, the composite multi-layer metal is used as the conductive layer of the flexible micro-needle-point array electrode, so that the contact impedance of the flexible micro-needle-point array electrode is reduced.

The invention relates to the technical field of solar cells, in particular to a laminated solar cell and a photovoltaic module. In the embodiment of the invention, the area of the orthographic projection of a first passivation contact layer on a reference surface is configured to be smaller than the area of the overlapping projection of a top cell unit and a bottom cell unit, and a first passivation layer is arranged on a first sub-surface exposed by the first passivation contact layer and a first target surface of the first passivation contact layer. The opposite side surfaces of the composite layer and the first passivation layer are in contact with each other, so that the efficiency of the battery can be improved.

The invention relates to the technical field of chip preparation, and provides a chip based on an annular photonic crystal and a preparation method thereof. The preparation method comprises the following steps: growing a nucleating layer on a substrate; growing a superlattice structure on one side, away from the substrate, of the nucleating layer; sequentially growing an n-type coating layer, an n-type waveguide layer, a quantum well and a p-type electron blocking layer on one side, deviating from the nucleating layer, of the superlattice structure; etching a plurality of annular cavities on the p-type electron barrier layer to form an annular photonic crystal; growing a p-type extension contact layer on one side, deviating from the quantum well, of the p-type electron blocking layer; and carrying out in-situ annealing treatment. According to the preparation method, the directivity of the photonic band gap can be effectively adjusted, uniform light waves in all directions on the side face can be formed, so that leakage of laser from a non-light-emitting area on the side face is restrained, the light emitting efficiency is improved, the annular photonic crystals are periodically distributed, and the light beam quality is effectively guaranteed.

The invention relates to the technical field of semiconductors, in particular to a source heterojunction contact semiconductor structure and device and a manufacturing method, the semiconductor structure comprises a gate structure, a body region structure, a source structure and a drain structure, and the source structure comprises a polycrystalline silicon source contact layer; the semiconductor structure comprises a body region structure and a polycrystalline silicon source contact layer, the body region structure is surrounded by the gate structure, a source contact region is arranged in the body region structure, the polycrystalline silicon source contact layer is in contact with the source structure through the source contact region so as to form a heterojunction diode with the source structure, and the heterojunction diode is a freewheeling diode of the semiconductor structure. The drain electrode structure is located on one side, back to the gate electrode structure, of the body region structure; the semiconductor structure can be a SiC MOSFET structure, reverse conduction voltage drop during follow current of the SiC MOSFET can be greatly reduced, and conduction loss and loss caused during switching are reduced.

The invention discloses a quick response flexible temperature sensor with low thermal crosstalk and a preparation method thereof. The sensor comprises a contact layer, a sensing layer, an electrode layer and a substrate layer, wherein the contact layer comprises a heat conduction layer and a heat insulation network; the heat-conducting layer is made of a heat-conducting composite material and comprises polydimethylsiloxane and flake carbon powder; the heat insulation network and the substrate layer are made of a heat insulation composite material which comprises polydimethylsiloxane and hollow glass microspheres; the sensing layer comprises a plurality of sensing units arranged in an array, the sensing units are connected with the electrode layer and output resistance signals, the heat conduction layer and the substrate layer are arranged over and under the sensing units respectively, and the heat conduction and heat insulation synergistic structure can enhance the quick response of the sensing units to the temperature; a thermal insulation network is embedded in the contact layer to block thermal crosstalk between adjacent sensing units. The temperature sensor has the advantages of quick response, low thermal crosstalk and high reliability in a wide range, and large-scale production and preparation can be realized.

The device comprises a pre-stretching elastic film layer which is sequentially stacked, a gradient drainage layer is arranged below the pre-stretching elastic film layer, and sealing edges are arranged on the outer edges of the pre-stretching elastic film layer and the gradient drainage layer. The sealing edge surrounds the edges of the pre-stretching elastic film layer and the gradient drainage layer and is used for being bonded with the skin to form a closed cavity. Continuous negative pressure is provided through retraction force of the pre-stretched elastic thin film layer, compared with a traditional external pump, the cost is lower, use is more convenient, adhesion with a postoperative wound part is prevented through the arrangement of the anti-adhesion contact layer, and the postoperative wound part is prevented from being damaged. And meanwhile, the anti-adhesion contact layer is provided with a micron-sized bulge array and nano-sized surface textures, so that the anti-adhesion effect is further ensured, and the drainage efficiency is improved through the design of the gradient drainage layer.

The invention discloses a preparation method and a structure of a photonic integrated device, and the method comprises the steps: sequentially dividing a substrate into a front modulator region, a rear modulator region, a front grating region, a gain region and a rear grating region, and growing a first active layer after manufacturing a selected region epitaxial mask pattern in the gain region, the method comprises the following steps of: growing a first active layer in a front modulator region after mask etching operation, growing a second active layer in a front modulator region after mask etching operation, growing a third active layer in a grating region after mask etching operation, finally performing grating manufacturing, and completing manufacturing of a cladding layer, an electric contact layer, an inverted table shallow ridge waveguide structure, an electric isolation trench and an electrode. According to the method, integration of multiple materials is achieved through one-time selective area epitaxial growth and one-time butt joint growth, the material growth frequency is reduced, and the manufacturing cost is saved; the gain region and the rear modulator region realize forbidden band width offset through selective region epitaxial material growth, and multi-wavelength tuning and efficient modulation are realized through fluorescence wavelength difference design of each region, so that a solution can be provided for integration of a wide-wavelength tunable laser and a double-electro-absorption modulator.

The invention provides a semiconductor laser chip with a current modulation function and a preparation method, and relates to the field of semiconductor laser chips, and the semiconductor laser chip comprises a substrate layer, an n-type limiting layer, an n-type waveguide layer, a quantum well active region, a p-type waveguide layer, a first p-type limiting layer, a second p-type limiting layer and a contact layer which are sequentially stacked from bottom to top, the anti-reflection cavity surface and the high-reflection cavity surface are arranged on the two opposite sides of the second p-type limiting layer, the functional area is arranged between the anti-reflection cavity surface and the high-reflection cavity surface and comprises a current injection sub-area and a current blocking sub-area, the current injection sub-area is provided with a plurality of injection tips, the current blocking sub-area is provided with a plurality of blocking tips, and the injection tips and the blocking tips are arranged on the first p-type limiting layer. The injection tip is arranged between any two adjacent blocking tips; two grooves formed in the first p-type limiting layer penetrate through the second p-type limiting layer and the contact layer, and the two grooves are located in the two opposite sides of the current injection sub-region and the current blocking sub-region. According to the semiconductor laser chip, the light emitting power and the light beam quality of the semiconductor laser chip can be improved.

The present disclosure relates to a photovoltaic device comprising a first contact layer (120) having a first thickness, a first charge transport layer (CTL, CTL ') having a second thickness positioned over a surface of the first contact layer, a semiconductor device (100) includes a first CTL (120) having a first thickness, an absorber layer (140) having a third thickness positioned over a surface of the first CTL, a second CTL (150) having a fourth thickness positioned over a surface of the absorber layer, a second contact layer (170) having a fifth thickness positioned over a surface of the second CTL, a barrier layer (180) having a sixth thickness, an encapsulation layer (190), and a first scribe line (P3) defined by at least one surface.

The invention relates to the technical field of semiconductor lasers, in particular to a vertical-cavity surface-emitting semiconductor laser and a manufacturing method thereof.The vertical-cavity surface-emitting semiconductor laser comprises a substrate, an N-type DBR layer, an active region, an oxide layer, a P-type DBR layer, a P contact layer and a P metal layer which are sequentially arranged from bottom to top, oxidation holes are formed in the oxide layer, a carbon displacement modulation structure layer is arranged in the P contact layer, and the P metal layer is arranged in the N-type DBR layer. The lower end of the carbon displacement modulation structure layer is located in the P-type DBR layer, the carbon displacement modulation structure layer is right opposite to the oxidation hole, and the material of the carbon displacement modulation structure layer is GaAs doped with carbon atoms. The high-frequency characteristic, single-mode performance, ultra-long service life, wide-temperature work and extreme environment resistance which are difficult to reach by a traditional pure oxidation limiting scheme and a traditional diffusion technology and oxidation limiting VCSEL scheme are achieved through cooperation of precise control of the SEG technology and the ultra-low diffusion characteristic of carbon.

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 invention discloses a group III chloride ex-situ doped cadmium telluride thin film solar cell and a preparation method thereof, and the cadmium telluride thin film solar cell comprises a substrate layer, a transparent conductive oxide thin film layer, a high-resistance buffer layer, a cell window layer, a cell layer, a back contact layer and a back electrode layer which are sequentially arranged from bottom to top. The cell layer comprises an absorption layer and a IIICl3 layer coated on the upper surface of the cell window layer, and IIICl3 is chloride of the III main group element. According to the III-group chloride ex-situ doping method provided by the invention, the III-group chloride can be dissolved in an organic solution, room-temperature solution deposition is allowed, III-group cations are easy to diffuse at a relatively low annealing temperature, and a complex annealing process is not needed to activate a dopant; through a simple solution process and low-temperature activation, efficient doping of the CdTe absorption layer is effectively realized, and the open-circuit voltage and the overall photoelectric conversion efficiency of the cell are remarkably improved.

The present application discloses a cell contact structure, a semiconductor device, and a method for fabricating the semiconductor device. The cell contact structure includes a contact layer positioned on a substrate and enclosed by a plurality of bit line structures and a plurality of partition layers; and a liner layer positioned between the contact layer and the substrate, between the contact layer and the plurality of bit line structures, and between the contact layer and the plurality of partition layers. A top surface of the contact layer and a top surface of the liner layer are substantially coplanar. The liner layer includes doped polycrystalline silicon, doped polycrystalline germanium, or doped polycrystalline silicon germanium. The contact layer includes tungsten, titanium, or titanium nitride.

The invention relates to the technical field of semiconductor light-emitting devices, and particularly discloses an epitaxial structure for improving the internal quantum efficiency of a green Micro LED. The epitaxial structure comprises a substrate, and a buffer layer, an undoped GaN layer, an n-type GaN layer, a stress release layer, an active layer, a low-temperature Mg heavily-doped GaN layer, an electron barrier layer, a p-type GaN layer and a p-type GaN contact layer which are sequentially arranged on the substrate. The active layer comprises a plurality of periods of InGaN quantum well layers and an InAlGaN / GaN superlattice quantum barrier layer alternating structure, and a CAP layer formed by an AlGaN / GaN superlattice is arranged behind each quantum well layer. By adopting a wide-well narrow-barrier structure, a superlattice CAP layer for neutralizing a polarization electric field and a quaternary InAlGaN barrier structure for lattice matching and hole injection enhancement, multiple regulation and control of a polarization field, dislocation density and hole transport are realized, the internal quantum efficiency of a green-light Micro LED is remarkably improved, and the green-light Micro LED epitaxial structure is suitable for epitaxial preparation of a high-performance Micro LED chip.

The invention provides a mid-infrared high-speed waveguide type modulator capable of being integrated on a chip and a design method, and belongs to the technical field of semiconductor optoelectronic devices, aiming at solving the problem that an existing mid-infrared modulator cannot consider high speed, low loss and on-chip integration compatibility at the same time. The modulator comprises an InP substrate, an epitaxial structure growing on the InP substrate and a traveling wave electrode structure prepared on the epitaxial structure. The epitaxial structure sequentially comprises an InP contact layer, an InAlAs lower light limiting layer, an InP / InGaAs lower waveguide layer, an asymmetric multi-quantum well structure, an InP / InGaAs upper waveguide layer, an InAlAs upper light limiting layer and a Cap layer from bottom to top. The design method comprises the steps of selecting a compatible material system, designing an asymmetric multi-quantum well structure, processing an epitaxial structure into a ridge waveguide structure, designing a traveling wave electrode and carrying out device characterization testing. The method is suitable for design and preparation of the middle-infrared band high-speed light modulation device.

A two-dimensional photonic crystal surface emitting laser includes an n-doped substrate, an n-doped cladding layer, an active layer, a photonic crystal layer, a p-doped cladding layer and a p-doped contact layer arranged in sequence from top to bottom. The photonic crystal layer includes a base material and a plurality of unit cells arranged periodically, each unit cell includes a first different-refractive index region, a second different-refractive index region and a third different-refractive index region that have a different refractive index from the base material. The surface emitting laser based on the photonic crystal structure may maintain single-mode operating characteristics of a device under a large mode field area, so that a high-power single-mode surface emitting laser may be achieved.

The utility model provides an electrocardiogram electrode patch. The electrocardiogram electrode patch comprises a transmission part, a first attaching part and a connecting wire, the transmission part is used for being detachably connected with electrocardiogram detection equipment, and the first attaching part is used for being attached to a to-be-detected first target position; the transmission part is connected with the first attaching part through the connecting line; the transmission part comprises a shielding grounding contact and a first transmission contact; the first attaching part comprises a first flexible circuit board, and the first flexible circuit board comprises a first shielding layer and a detection contact layer; the connecting line comprises a signal transmission core and a second shielding layer wrapping the signal transmission core. The first shielding layer is connected with the shielding grounding contact through the second shielding layer, and the detection contact layer is connected with the first transmission contact through the signal transmission core. By means of the configuration, signals and interference signals can be transmitted independently, and the stability of electrocardiosignal transmission can be effectively improved.

The invention discloses a semiconductor laser and a preparation method thereof, which can be used in the field of semiconductor device preparation, and the method comprises the steps: firstly, providing a first conductive type substrate; then, epitaxially growing a buffer layer of a first conduction type, a lower optical waveguide limiting layer, a quantum well active light-emitting layer, an upper optical waveguide limiting layer, a corrosion barrier layer, a current injection layer and an intrinsic ohmic contact layer on the substrate in sequence to obtain a multi-layer epitaxial layer; then, etching the multi-layer epitaxial layer to the corrosion barrier layer based on a preset pattern to form a ridge-shaped table which starts from the intrinsic ohmic contact layer and is deeply cut off to the corrosion barrier layer; and finally, performing particle doping in a region corresponding to the ridge-shaped table, and converting one sides, close to the corrosion barrier layer, of the intrinsic ohmic contact layer, the current injection layer, the corrosion barrier layer and the upper optical waveguide limiting layer into a second conduction type. Therefore, current limitation can be realized without performing multiple epitaxy like a traditional buried heterojunction, and the production cost and the process difficulty are greatly reduced.