13results about How to "Decrease the density of surface states" patented technology

The invention discloses a cavity surface treatment method of a semiconductor laser and the semiconductor laser, and the method comprises the steps: stacking and placing laser chips subjected to atmospheric cleavage and pretreatment into a sample injection cavity for first heat treatment, and then sequentially carrying out second heat treatment, injecting reducing gas for impact and carrying out third heat treatment in a growth cavity, injecting fluorine-containing ion source gas to perform surface fluorination treatment on the surface of the GaAs substrate so as to generate a wide-band-gap metal fluorination layer with a first thickness on the surface of the GaAs substrate, injecting hydrogen-containing nitrogen ion source gas and an evaporation metal aluminum source, and generating a hydrogenated aluminum nitride layer with a second thickness on the metal fluorination layer, and a passivation layer composed of the metal fluorination layer and the hydrogenated aluminum nitride layer is obtained. According to the invention, the surface state density of the cavity surface of the GaAs-based semiconductor laser can be reduced, and the optical catastrophe damage resistance is enhanced, so that the performance and reliability of the semiconductor laser are improved.

The invention relates to the technical field of electronic components, in particular to a preparation process of a low-dimensional material field effect transistor surface gate dielectric layer, which comprises the following steps: S1, placing a substrate in a cavity of an ALD reaction device, S2, introducing a hydrogen peroxide precursor into the cavity for surface adsorption, and then purifying the cavity; s3, the temperature in the cavity is increased to 50-200 DEG C from the room temperature, metal source steam formed in the metal source bottle is brought into the cavity by high-purity nitrogen through a pipeline and reacts with the hydrogen peroxide precursor adsorbed on the surface of the low-dimensional material, and then the cavity is purified; s4, repeating the steps S2 and S3 for multiple times, and forming a primary gate dielectric layer on the surface of the low-dimensional material; switching an oxygen source from a hydrogen peroxide source to an ozone source, and continuing to grow a gate dielectric layer under a high-temperature condition. According to the preparation process, the structure of the material cannot be damaged, the primary dielectric layer can have good compactness, and meanwhile all the advantages of preparing the gate dielectric layer under the high-temperature and high-oxidation conditions are achieved.

The invention provides an epitaxial layer structure of a doped InSb film and a preparation process thereof, based on an MOCVD (Metal Organic Chemical Vapor Deposition) process, an InSb: Te layer and an InSb layer are periodically and alternately grown to form a doped InSb functional layer of a Hall element, the band gap of an InSb material can be increased, and the temperature coefficient of the Hall element of the InSb film is reduced; furthermore, according to the epitaxial layer structure and the preparation process provided by the invention, uniform doping can be realized, excessive Te doping can be avoided, and the defect density and the surface state density of the doped InSb functional layer can be reduced, so that the sensitivity of the InSb Hall element is improved, and the background noise of the Hall element is reduced. Besides, according to the epitaxial layer structure of the doped InSb film and the preparation process thereof provided by the invention, the growth processes, materials, thicknesses and the like of the buffer layer and the gradient layer are further improved, lattice mismatch between the substrate and the InSb film is slowed down, the dislocation density of the InSb film caused by mismatch is reduced, the InSb film with higher mobility can be grown, and the yield of the InSb film is improved. And therefore, higher sensitivity can be obtained on the Hall element.

The invention discloses a structure and a method for improving the two-dimensional electron gas concentration of an HEMT (High Electron Mobility Transistor) device. The structure for improving the two-dimensional electron gas concentration of the HEMT device comprises an epitaxial structure, a source electrode, a drain electrode and a grid electrode, the source electrode, the drain electrode and the grid electrode are matched with the epitaxial structure, the epitaxial structure comprises a channel layer, a barrier layer and a lithium phosphate cap layer, the channel layer and the barrier layer are stacked, and a carrier channel is formed at an interface between the channel layer and the barrier layer. And the lithium phosphate cap layer is coated on the epitaxial structure. According to the invention, an additional semiconductor manufacturing process near the grid electrode is avoided, a large number of surface states are prevented from being introduced, the dynamic characteristics of the device are improved, and the concentration of 2DEG is also improved.

The invention discloses a mesa type PIN photoelectric detector based on epitaxial Ge on Si and a preparation method, and relates to the technical field of semiconductor photoelectric devices. The detector comprises an N-type silicon Si substrate, a mesa structure formed by an intrinsic Ge layer and a P-type heavily-doped Ge layer which are sequentially and epitaxially arranged on the N-type silicon Si substrate, a passivation layer covering a mesa, and a metal electrode respectively connected with the P-type heavily-doped Ge layer and the N-type silicon Si substrate. According to the invention, the size of a germanium active region is greatly reduced by adopting a structure that a thin layer Ge is extended on the Si substrate and mesa isolation is combined, and generation and recombination of carriers are inhibited by cooperation of a Si / Ge heterojunction and side wall passivation, so that the dark current of the device is remarkably reduced. Meanwhile, by accurately controlling the thickness of the intrinsic Ge layer, flexible optimization can be carried out between high responsivity and high bandwidth, and the requirements of different near-infrared application scenes are met.

The present invention relates to the technical field of solar cells, and in particular to a high-performance passivation film for heterojunction solar cells and a preparation method thereof, comprising the following steps: depositing five layers of silicon-based films and hydrogen treatment layers on a textured silicon substrate in sequence, wherein the five layers of silicon-based films are an interface anti-epitaxial layer, a transition layer, a wide-bandgap transition layer, a wide-bandgap dense layer and a dense barrier layer in sequence. The multi-layer arrangement and thickness ratio in the passivation film of the invention can ensure the stability of the series resistance and fill factor of the battery terminal.

The invention provides a preparation method and application of a heterojunction cell substrate, and the method comprises the following steps: sequentially depositing an intrinsic passivation layer, a first doping layer and a silicon nitride layer on the first surface of an initial substrate, and then carrying out the annealing treatment to obtain an intermediate substrate, the refractive index of the silicon nitride layer being 1.5-2; a texturing agent is used for texturing the middle substrate, after a textured surface is formed on the second surface of the middle substrate, first cleaning treatment is carried out, then silicon nitride layer removal treatment and oxide layer removal treatment are carried out on the middle substrate, and the second surface and the first surface are oppositely arranged; and sequentially depositing an intrinsic passivation layer and a second doping layer on the surface, far away from the initial substrate, of the suede to form the heterojunction cell substrate. According to the method, the back surface of the heterojunction cell substrate has excellent flatness, meanwhile, the fragment rate of the heterojunction cell substrate is reduced, the interface passivation effect is enhanced through silicon nitride annealing and hydrogen injection, and then the short-circuit current, the open-circuit voltage, the filling factor and the photoelectric conversion efficiency of the heterojunction solar cell are improved.

The present application provides a gallium oxide back-passivated solar cell and a preparation method therefor. The solar cell comprises a P-type silicon substrate. A front coating and a back coating are respectively provided on two opposite side surfaces of the P-type silicon substrate. The front coating comprises an emitter, a front silicon oxide layer, and a front silicon nitride layer which are sequentially stacked from the surface of the P-type silicon substrate to the outside. The back coating comprises a silicon oxide passivation layer, a gallium oxide passivation layer, and a back passivation layer which are sequentially stacked from the surface of the P-type silicon substrate to the outside.

This application relates to the field of photovoltaic technology, and particularly to perovskite solar cells, tandem solar cells, and photovoltaic modules. The perovskite solar cell includes a perovskite light-absorbing layer, which comprises perovskite material and amino-functionalized polymer additives. The perovskite material includes materials with the general formula ABX3, where A ions are monovalent cations and B ions include Pb. 2+ The X ion is a monovalent anion; the amino-functionalized polymer additives include at least one selected from polyethyleneimine, polypropyleneimine, amino-functionalized polyetherimide, amino-functionalized polyvinylpyrrolidone, amino-functionalized polyvinyl alcohol, amino-functionalized polyacrylic acid, and amino-functionalized polyquaternary ammonium salt. This application adds amino-functionalized polymer additives to the perovskite light-absorbing layer to passivate defects at perovskite grain boundaries, reduce surface state density, prolong carrier lifetime, increase short-circuit current density, enhance the bending resistance of the perovskite light-absorbing layer, and improve the environmental stability of the device.

The invention provides a preparation method of a battery edge passivation composite film layer and a battery piece, and the method comprises the following steps: placing a sliced substrate in a magnetron sputtering cavity, and controlling the temperature of the substrate at 25-250 DEG C; sputtering a first target material by using a first medium-frequency power supply so as to deposit and form a passivation buffer layer on the substrate; sputtering a second target material by using a radio frequency power supply so as to deposit and form a passivation layer on the passivation buffer layer; sputtering a third target material by using a second medium-frequency power supply to deposit and form a passivation protection layer on the passivation layer to obtain a substrate with a passivation composite film layer; and the substrate with the passivation composite film layer is put into an annealing furnace to be subjected to an annealing process, and the temperature range is 100-300 DEG C. Compared with the prior art, the method provided by the invention is suitable for temperature-sensitive low-temperature process batteries such as heterojunction batteries, HBC batteries, HTBC batteries and the like, and passivation is realized without sacrificing the performance of the battery body.

The invention provides a preparation process of an efficient crystalline silicon solar cell, and belongs to the technical field of solar cells. Comprising the following steps: texturing and carrying out front boron diffusion; preparing a tunneling oxide layer and a polycrystalline silicon layer; preparing a double-layer coated silicon wafer; preparing binary complex solid powder; preparing a doped antireflection film; and preparing a metal electrode. The preparation method comprises the following steps: dissolving europium oxide in concentrated hydrochloric acid to prepare a mixed chloride, dissolving the mixed chloride in ethanol, carrying out a series of reactions to prepare binary complex solid powder, adding the binary complex solid powder into silicon dioxide sol, and carrying out dip coating on a double-layer coated silicon wafer to obtain the europium-doped silicon wafer. After the doped anti-reflection passivation films are formed on the front and back surfaces, the doped anti-reflection passivation films can convert ultraviolet light which is difficult to absorb by the crystalline silicon solar cell into visible light with good spectral response, so that the light absorption efficiency of the solar cell is improved, and the effect of improving the conversion efficiency of the crystalline silicon solar cell is achieved.

The invention relates to the technical field of gallium nitride semiconductors, and discloses a preparation method of a gallium nitride semiconductor device, which comprises the steps of providing a substrate piece of a semiconductor substrate, depositing and forming a buffer layer on the top of the substrate piece, vapor-depositing a gallium nitride layer on the top of the buffer layer, and forming a channel layer on the top of the gallium nitride layer, a barrier layer is formed on the surface of the top of the channel layer, an aluminum gallium nitride layer is formed on the top of the barrier layer in a vapor deposition mode, a P-type cap layer grows on the top of the aluminum gallium nitride layer, and a passivation layer is formed on the top of the aluminum gallium nitride layer and the top of the P-type cap layer in a deposition mode. According to the preparation method of the gallium nitride semiconductor device, the first doping layer and the second doping layer are formed inside the barrier layer and on the surface of the top of the barrier layer, the channel electron concentration can be increased or the surface state density of the barrier layer can be reduced, and the thin P-type cap layer grows on the top of the gallium nitride aluminum layer; the P-type cap layer and the passivation layer can well improve the current collapse effect.