12results about How to "Increase the bandgap width" patented technology

The invention belongs to the technical field of back contact cells, and particularly relates to a back contact cell with a passivated specific light receiving surface and a preparation method and application thereof.The back contact cell comprises a substrate, the substrate is provided with a backlight surface and a light receiving surface, the light receiving surface of the substrate is sequentially provided with a first tunneling oxide layer, a doped amorphous silicon layer and a silicon medium anti-reflection layer, the thickness of the first tunneling oxide layer is 0.2-1.5 nm, and the thickness of the doped amorphous silicon layer is 0.2-1.5 nm; the doped amorphous silicon layer is doped with an oxygen element and a hydrogen element, the first tunneling oxide layer is doped with a hydrogen element, and the content of the hydrogen element close to the side of the doped amorphous silicon layer in the first tunneling oxide layer is greater than the content of the hydrogen element close to the side of the substrate. According to the invention, good passivation effect and optical loss can be taken into account, and the passivation effect is enhanced, so that the passivation effect and current of the battery are improved, the efficiency of the battery is improved, and the equipment cost is low.

The invention discloses a low-absorption high-emission radiation refrigeration coating material, which comprises a bottom coating and a surface coating, the bottom coating comprises BaSO4 with different particle sizes and a film forming substance, and the surface coating comprises a surface layer filler and a film forming substance. The invention also discloses a preparation method of the material, which comprises the following steps: dispersing and mixing BaSO4 with different particle sizes, a film-forming substance and a solvent to obtain bottom layer slurry, and filtering to obtain a bottom layer coating; dispersing and mixing a surface layer filler, a film-forming substance and a solvent to obtain surface layer slurry, and filtering to obtain a surface layer coating; the prime paint is sprayed on the surface of the base material, and then the surface paint is sprayed on the surface of the prime paint; and curing to obtain the coating. The material has excellent solar spectrum reflection performance, high infrared radiation performance of an atmospheric window and relatively good ultraviolet aging resistance, and can be applied to multiple fields of high-end optical instrument detection, communication electronics, petrochemical engineering, energy-saving buildings and the like.

The invention discloses a light-emitting diode epitaxial wafer and a preparation method thereof, and relates to the technical field of semiconductor devices. The light-emitting diode epitaxial wafer comprises a silicon substrate, and a buffer layer, a non-doped AlGaN layer, an N-type AlGaN layer, a multi-quantum well layer, an electron barrier layer, a P-type AlGaN layer and a P-type contact layer which are sequentially stacked on the silicon substrate, the buffer layer comprises an oxide layer and a barrier layer which are sequentially stacked on the silicon substrate; the oxide layer comprises a three-dimensional Si gradient doped Ta2O5 layer, a three-dimensional Si gradient doped Ga2O3 layer and a two-dimensional (AlGa) 2O3 layer which are stacked in sequence; the barrier layer comprises a three-dimensional Mg-H doped BAN layer and a two-dimensional Si3N4 layer which are stacked in sequence. According to the light-emitting diode epitaxial wafer, electric leakage channels can be reduced, the crystal quality is improved, the photoelectric property of an LED device is improved, and the problem of high leakage current of a silicon substrate GaN-based LED is solved.

The utility model relates to a kind of LED epitaxial structures, comprising: substrate;N type layer;Active layer is located on N type;P type layer, located on active layer;Wherein, the P type layer includes P type window layer, P type window layer includes several first laminated structure, each first laminated structure includes the GaInP layer, first GaP layer and second GaP layer of sequentially laminated, the P type doping concentration of second GaP layer in each first laminated structure is greater than the P type doping concentration of first GaP layer.The GaInP layer of the utility model has higher band gap, plays the role of optical window layer, can reduce light absorption loss;GaP has lower band gap, first GaP layer and second GaP layer play the role of buffer layer / transition layer, so the combination of GaInP layer, first GaP layer and second GaP layer realizes the balance of band matching and carrier transport efficiency, conducive to the efficient extension of current.

The present invention discloses a dye-sensitive solar cell based on a composite structure photoanode and a preparation method and application thereof. The preparation method of the dye-sensitive solar cell comprises the following steps: S1: preparing an Au / SnS / TiO2 composite structure photoanode; S2: preparing an I-rich ‑ and I3 ‑ electrolyte; S3: prepare natural dye blueberry juice; S4: prepare graphite counter electrode; S5: assemble Au / SnS / TiO2 composite structure photoanode, electrolyte, natural dye and counter electrode into dye-sensitive solar cell. The dye-sensitive solar cell prepared by the Au / SnS / TiO2 composite structure photoanode and natural dye by spin coating and high-temperature calcination in the present invention has good photoelectric conversion efficiency and stability. It is applied to the sunroof of electric vehicles, which can not only retain the original function of the sunroof of the car, but also generate electricity to charge the car, greatly saving the original charging time and charging cost of the electric car, and also eliminating the trouble of queuing to use the charging pile.

The embodiment of the invention provides projection equipment, a laser television and a vehicle, the projection equipment comprises an MEMS galvanometer chip, the MEMS galvanometer chip adopts silicon carbide as a chip substrate, and compared with a silicon-based chip, the silicon carbide has the characteristics of high thermal conductivity, high forbidden band width and the like, and the MEMS galvanometer chip has the advantages of high thermal conductivity and high forbidden band width. According to the MEMS galvanometer chip, the rotating suspension beam integrated with the mirror surface in the projection equipment using the MEMS galvanometer chip is not easy to damage at high temperature and low in heat dissipation requirement, the problems caused by working temperature rise such as fusing of the rotating suspension beam are avoided, the projection equipment has better environment adaptability, the heat dissipation requirement is low, the heat dissipation structure can be reduced, and the projection equipment is more miniaturized.

A method for preparing and applying a cross-linked network polyimide composite material based on electron-withdrawing groups is disclosed, relating to the field of high-temperature energy storage technology for electrolyte capacitors. Method: 3,5-tris(4-amino-2-trifluoromethylphenoxy)benzene is added to a polyimide colloidal solution and stirred uniformly under a nitrogen atmosphere to obtain solution b; solution b is evacuated and then uniformly coated onto one side of a pretreated substrate. After curing, the substrate is subjected to gradient heating, and finally the film on the substrate is peeled off to obtain the cross-linked network polyimide composite material based on electron-withdrawing groups; the application of the cross-linked network polyimide composite material based on electron-withdrawing groups in dielectric capacitors. This invention provides a method for preparing and applying a cross-linked network polyimide composite material based on electron-withdrawing groups.

The invention discloses a preparation method of a graphene-diamond composite material, which comprises the following steps: depositing a diamond film on the surface of monocrystal diamond by adopting a microwave chemical vapor deposition method, and respectively preparing monocrystal diamond films with (100), (110) or (111) oriented upper and lower surfaces by adopting a slicing and polishing method; processing the surface of the monocrystal diamond film through hydrogen plasma by utilizing a microwave plasma technology to obtain monocrystal diamond with a hydrogen terminal surface; in a high vacuum environment, a tungsten filament is utilized to generate hot electrons, and high voltage is applied to generate high-energy electron beams; and leading a high-energy electron beam to the surface of the monocrystal diamond with the hydrogen terminal surface by using a bias technology for bombardment, and converting carbon atoms on the surface into a graphene stacked structure to obtain the graphene-diamond composite material. According to the method disclosed by the invention, a carbon source is not additionally introduced, and the diamond is directly used as a subsequent substrate, so that damage caused by a graphene transfer technology is avoided.

The invention discloses a superstructure for shock absorption and impact resistance functions of a linear separation device. The superstructure comprises an impact reduction structure unit and an external frame, wherein the outer frame is of a cuboid structure, a hollow cavity is formed in the outer frame, the impact reduction structure unit is of a phonon crystal structure and is composed of two local resonance units which are transversely arranged in the hollow cavity side by side, and the center position of each local resonance unit is provided with one center position mass block; the upper end and the lower end of the central position mass block are connected with the upper side and the lower side of the external frame through two spiral connecting rods respectively to form a central resonant cavity. The impact reduction structure unit forms double band gaps through local resonance so as to reduce explosion separation impact. When the device is applied to an aircraft, explosion separation local resonance impact reduction can be achieved, meanwhile, scattering and attenuation of stress waves can be achieved, and the purpose of reducing the explosion separation impact environment is achieved.

The present invention belongs to the technical field of wastewater treatment, and specifically relates to a method for treating ammonia nitrogen wastewater containing heavy metals. The treatment method comprises preparing and modifying C3N4 nanosheets, adding a forming agent and the prepared modified C4N3 nanosheets to a polar organic solvent for blending, and preparing a photocatalytic cation exchange membrane through forming, film scraping, and solidification; and placing the photocatalytic cation exchange membrane in an electrolytic cell, with an anode chamber and a cathode chamber on both sides, and placing ammonia nitrogen wastewater containing heavy metals and sulfuric acid respectively, using a light source to irradiate the photocatalytic cation exchange membrane to catalyze the degradation of ammonia nitrogen, and at the same time, making the heavy metal ions complexed with ammonia nitrogen become free heavy metal ions; after the heavy metal ions pass through the photocatalytic cation exchange membrane, they are reduced at the cathode through electrolysis to obtain metal elements. The present invention can remove ammonia nitrogen and heavy metals at the same time, and has the advantages of low energy consumption, low use cost, and thorough treatment without secondary pollution.

The invention discloses a Micro LED epitaxial structure and a preparation method thereof, and relates to the technical field of semiconductor devices. The Micro LED epitaxial structure comprises a substrate, and a buffer layer, a U-GaN layer, an N-GaN layer, a multi-quantum well layer, an electron blocking layer, a P-GaN layer and a contact layer which are sequentially stacked on the substrate, the contact layer comprises a depletion layer and an annealing layer which are stacked in sequence; the depletion layer comprises a Mg-doped GaN layer and a Si-doped BGaN layer which are stacked in sequence; the annealing layer comprises a Ta2O5 layer, a Ga2O3 layer and a Mg doping gradient (AlGa) 2O3 layer which are sequentially stacked. When the Micro LED epitaxial structure is used for preparing a chip, the current transverse expansion capability can be improved, the contact resistance can be reduced, the generation of an electric leakage channel can be reduced, and further the light emitting uniformity, the light emitting efficiency and the stability of the Micro LED chip can be improved.

The invention discloses a gallium nitride-based high electron mobility transistor and a preparation method thereof, and relates to the field of semiconductor technology. The transistor includes a substrate, and a buffer layer, at least one first composite insertion layer, a channel layer, at least one second composite insertion layer, a barrier layer and a cap layer stacked on the substrate in sequence; wherein the first composite insertion layer and the second composite insertion layer each include at least two sublayers, and the two sublayers are an AlN sublayer and an AlInGaN sublayer, respectively; the barrier layer is an AlInN layer with an Al component and an In component ratio of 4:1-6:1, and the channel layer is a GaN layer. Through this arrangement, the lattice mismatch between the barrier layer and the channel layer is within 0.5%, and the lattice of the barrier layer and the channel layer is basically matched, thereby significantly improving the crystal quality of the barrier layer, and because the Al component and the In component ratio are within the range of 4:1-6:1, the band gap difference between the barrier layer and the channel layer is extremely large, thereby realizing the preparation of a relatively thin barrier layer, and at the same time, a higher two-dimensional electron gas concentration can be obtained.