55results about How to "Reduce surface state" patented technology

The present invention is directed to systems and methods for nanowire growth and harvesting. In an embodiment, methods for nanowire growth and doping are provided, including methods for epitaxial oriented nanowire growth using a combination of silicon precursors. In a further aspect of the invention, methods to improve nanowire quality through the use of sacrifical growth layers are provided. In another aspect of the invention, methods for transferring nanowires from one substrate to another substrate are provided.

The invention provides an SiO2/SiN double layer passivation layer T-typed grid AlGaN/GaN HEMT which comprises: a substrate which is grown with a GaN buffer layer, a GaN intrinsic layer and an AlGaN barrier layer in order; source and drain electrodes which are provided on the barrier layer at two sides; a lower passivation layer which is provided between the source and drain electrodes and is on the barrier layer; an upper passivation layer which is provided between the source and drain electrodes and is on the passivation layer, wherein, a bar shaped grid groove is provided between the lower passivation layer and the upper passivation layer; a gate electrode whose section is a T shape, wherein, the gate electrode is provided in the bar shaped grid groove, and an upper part of the gate electrode is higher than a surface of the upper passivation layer.

The invention discloses a method for passivating a cavity surface of a GaAs-based semiconductor laser, and the method comprises the following steps of putting a cleaved laser bar into solution of sulphuret of ammonia to be immersed, carrying out passivation on the laser bar and depositing a sulfur passivation layer on a front cavity surface and a back cavity surface of the laser bar; washing the bar by deionized water, dehydrating by acetone and isopropanol and blow-drying by nitrogen, installing a film plating frame and putting into an MOCVD instrument; vacuumizing the MOCVD instrument, baking to heat and introducing protective gas; increasing the temperature of a substrate, sublimating an amorphous sulfur layer in the sulfur passivation layer, introducing a growth source, and epitaxial-growing a layer of ZnSe passivation protective film on the sulfur passivation layer; and after cooling, taking out the film plating frame and putting into a plating machine, and plating anti-reflection film and high-reflection film on the passivation protective film of the laser bar. The method removes an oxide layer and a surface state on the cavity surface effectively and reduces the damage on the cavity surface.

A method for passivating the cavity surface of an F-P cavity semiconductor laser, comprising the following steps: 1, cleaving the F-P cavity semiconductor laser to obtain a laser bar; 2, cleaning the front and rear cavity surfaces of the laser bar with nitrogen plasma; 3, applying epitaxy Growth technology epitaxially grows a layer of protective film on the front and rear cavity surfaces of the laser; 4. Evaporate or deposit an anti-reflection film on the front cavity surface of the laser bar, and evaporate or deposit a high-reflection film on the rear cavity surface; 5. Use segmentation or solution A reasonable approach divides the laser bar into individual laser chips or chip arrays. The invention can effectively reduce the dangling bonds and surface states at the laser cavity surface, and suppress the light absorption of the laser cavity surface; at the same time, the epitaxially grown thin film is a wide bandgap material, which absorbs very little outgoing light, and can greatly suppress the laser cavity The light absorption at the surface and the resulting temperature rise improve the stability and reliability of the laser.

The invention relates to a dye sensitization solar cell light anode and a preparation method thereof. The light anode is characterized in that chemical modification for the dye sensitization solar cell light anode improves the sensitization effect of the dye on the light anode, thereby improving the photoelectric conversion efficiency of the cell. The concrete realization method is to carry out the surface modification of light anode nano crystal through nano SiO2, carry out functionalization, and absorb the dye. The modification of a nano SiO2 layer inhibits the surface state of a nano crystalline film and improves the photoelectric conversion performance of the cell; and simultaneously the surface functionalization increases the absorption amount of the dye, thereby effectively improving the photoelectric conversion efficiency of the solar cell.

The invention discloses an interface treatment technology for a hetero junction solar cell. The method is characterized in that: the technology can be applied to the manufacturing of a thin film/crystalline silicon hetero junction solar cell, reaction gases can be ionized by utilizing a plasma enhanced chemical vapor deposition (PECVD) system or a hotwire chemical vapor deposition (HWCVD) system to generate H, and the H is transported to a crystalline silicon substrate by a gas phase and reacted with the surface of crystalline silicon to effectively passivate defect states such as unsaturated dangling bonds and the like on the surface of the crystalline silicon, reduce hetero junction interface recombination and facilitate improvement in the overall performance of the hetero junction solar cell.

The present invention is directed to systems and methods for nanowire growth and harvesting. In an embodiment, methods for nanowire growth and doping are provided, including methods for epitaxial oriented nanowire growth using a combination of silicon precursors, as well as us of patterned substrates to grow oriented nanowires. In a further aspect of the invention, methods to improve nanowire quality through the use of sacrifical growth layers are provided. In another aspect of the invention, methods for transferring nanowires from one substrate to another substrate are provided.

Disclosed is a bipolar semiconductor device which is capable of reducing the surface state density of a bipolar transistor and increasing the current gain of the transistor, thereby improving the transistor performance. A bipolar semiconductor device (100) has a surface protective film (30) on the surface of a semiconductor element. The surface protective film is composed of a thermal oxide film (31) formed on the surface of the semiconductor element, and a deposited oxide film (32) formed on the thermal oxide film. The deposited oxide film contains at least one of hydrogen element and nitrogen element in an amount of not less than 1018 cm-3.

The present invention mainly relates to a nuclear radiation detector, in particular, it relates to a position sensitive detector used in the high-energy physics and nuclear physics and its production process. Said detector includes silicon substrate, N-type, it is mainly characterized by that it also includes detection window, it is formed from mutually-parallelized detection windows, it has B+ doped region, forming PN Gunction, on it an Al-layer is set, and is equipped with a lead; between two windows an insulated separating zone is set; back surface of silicon substrate has P- doped region, forming N+ ohmic contact, on it an Al-layer is coated to form back electrode. Said invention also provides the concrete steps of its production method.

The invention belongs to the technical field of semiconductor materials and particularly relates to a gallium nitride enhanced HEMT device and a preparation method thereof. According to the method, ICP (Inductively Coupled Plasma) is adopted to optimize a gallium nitride conductive channel, oxygen plasma treatment is performed before an insulating dielectric layer is deposited, then in-situ annealing is performed, and a crystal GaON nano-phase is generated in a gate region to serve as an optimized channel layer. The method can effectively reduce the surface state of high-concentration impurities introduced by the inner wall of the groove due to the etching process and the morphology of the rough inner wall, improves the stability and reliability of the device, improves the breakdown voltage and on/off current ratio of the device, and further improves the working performance of the device.

The invention discloses a gallium nitride power device with a multi-field plate structure. The gallium nitride power device is sequentially provided with a substrate, a nucleating layer, a buffer layer, a first insertion layer, a first GaN layer, a second insertion layer, a second GaN layer, an AlGaN barrier layer, a passivation layer, a grid electrode field plate, a drain electrode field plate, aprotective layer, a grid electrode insertion layer, a p-type GaN grid electrode, a grid electrode metal, a source electrode metal and a drain electrode metal from bottom to top, wherein the passivation layer located on the surface of the AlGaN barrier layer is in a strip shape arranged at intervals, the grid electrode field plate and the drain electrode field plate respectively cover part of thepassivation layer, and the surfaces of the grid electrode field plate and the drain electrode field plate and the space between the grid electrode field plate and the drain electrode field plate are covered with the protective layer. According to the invention, the electric field distribution is uniform, the voltage endurance capability of the device is enhanced, the stability of grid electrode turn-on voltage and grid electrode voltage of the device is effectively improved, and the electric leakage of the device under the action of large current is effectively reduced. The preparation methodis completely compatible with a traditional process, and the preparation difficulty is low.

The invention discloses an InGaAs low mesa line series or area array infrared detector chip, which includes a line series or area array p-InP micro-mesa formed by etching on p-InP/InGaAs/n-InP epitaxial wafer. The p-InP micro-mesa is provided with an Au/Zn/Pt/Au/P electrode area in ohmic contact. A public N electrode area is etched to the n-InP layer on the side of the line series or area array micro-mesa and is positioned on the n-InP layer. Except for the P and N electrode areas, the whole epitaxial wafer and the lateral sides are covered by a silicon nitride passivation layer. The P electrode area is provided with an electrode interconnection area with a reading circuit. The electrode interconnection area covers a part of the micro-mesa and extends from the micro-mesa to a plane. The invention has the advantages of mesa decrease by retained InGaAs layer and effective protection on the InGaAs layer lateral sides. The silicon nitride passivation layer has effective function of reflection resistance and InP and InGaAs layer surface state reduction and can increase the detector quantum efficiency and decrease dark current. The P electrode adopts AuZnPtAu, forms good ohmic contact with p-InP and P can effectively prevent Zn from out diffusion and improve the device reliability.

The invention provides a thin film crystalline silicon perovskite heterojunction solar cell and a preparation method thereof, relates to a semiconductor device for converting optical energy to electric energy, and particularly provides a thin film crystalline silicon perovskite heterojunction solar cell having an electronic cavity composite suppression structure layer. The solar cell includes a transparent conductive substrate, a P-type thin film crystalline silicon layer, an electronic cavity composite suppression structure layer, a perovskite light absorption layer, an electronic transmission layer formed by compact titanium dioxide, and a back electrode. The perovskite light absorption layer and the P-type thin film crystalline silicon layer have matched energy levels, and the electronic cavity composite suppression structure layer formed by SiO2 is added between the P-type thin film crystalline silicon layer and the perovskite light absorption layer. The solar cell provided overcomes the defects of current leakage and internal short circuit of a thin film crystalline silicon perovskite heterojunction solar cell in the prior art.

The invention discloses a production method of a low-noise germanium-silicon heterojunction bipolar transistor, comprising the following steps of: step 1, applying a polysilicon layer for an emitting electrode of the germanium-silicon heterojunction bipolar transistor, doping the emitting electrode, then, executing quick thermal annealing, and diffusing and redistributing the impurities; step 2, executing pre-amorphization ion implantation with medium and high dosage of large atom impurities on the polysilicon emitting electrode, annealing quickly, realizing re-crystallization of the amorphous emitting electrode, and generating a single crystal layer, thereby forming an emitting area/base area junction by the monocrystal silicon/ monocrystal germanium and silicon; step 3, executing quick thermal annealing after the process of pre-amorphization ion implantation, and crystallizing the amorphous emitting electrode. With the method provided by the invention, the noise caused by a polysilicon emitting electrode is reduced, and noise characteristics of devices are improved.

The invention discloses a surface passivation structure for a III-V group nitride device and a device thereof. The surface passivation structure comprises an Al1-xScxN layer and an AlySc2-yO3 layer, the Al1-xScxN layer and the AlySc2-yO3 layer are located on a III-V nitride substrate, the Al1-xScxN layer and the AlySc2-yO3 layer are sequentially stacked from bottom to top, the thickness of the Al1-xScxN layer is 0.5-10 nm, x is larger than 0 and equal to or smaller than 1, the thickness of the AlySc2-yO3 layer is 1-20nm, y is more than or equal to 0 and less than 2, and the thickness of the Al1-xScxN layer is less than or equal to the thickness of the AlySc2-yO3 layer. Generation of an interface state can be further reduced, the risk of current collapse of the device is reduced, and the reliability of the device is improved.

The invention discloses a silicon heterojunction solar cell and a surface treatment method of a hydrogenated amorphous silicon i film layer thereof. Plasma treatment is carried out on the surface of the hydrogenated amorphous silicon i film layer by adopting a gas mixture of hydrogen and argon or hydrogen and helium, the hydrogenated amorphous silicon i film layer can be preferably cleaned in a physical manner through argon or helium plasmas, and the increase of the amount of the helium plasmas is further promoted, so that the passivating and cleaning effects for the surface of the hydrogenated amorphous silicon i film layer are strengthened; and moreover, slight damage to the surface of the hydrogenated amorphous silicon i film layer can be generated in the physical bombarding process of the argon or helium plasmas, and the hydrogen plasmas can play a passivating role on the surface of the hydrogenated amorphous silicon i film layer and can also repair the slight damage. Through the synergistic effect of the gas mixture of hydrogen and argon or hydrogen and helium, better passivating and cleaning effects can be achieved for the surface of the hydrogenated amorphous silicon i film layer, so that the battery performance is promoted.

The invention relates to a preparation technology of block amorphous alloy, in particular to a method for improving the forming ability and strength of amorphous alloy by controlling solidifying condition. The method has low process cost, is simple and easy, can obviously strengthen the forming ability of block amorphous alloy and improve the material strength and is suitable for a majority of amorphous systems. The casting is carried out when the preheating temperature of a die reaches 353-393K by adjusting the preheating temperature of the die through adopting a copper die casting method and the amorphous forming ability can be improved so that the amorphous alloy in a larger size can be obtained; meanwhile, the strength of an amorphous alloy material is improved by 4-18 percent. The invention develops a novel method for improving the forming ability of the block amorphous alloy, confirms a novel process parameter for producing the block amorphous alloy in larger size and improving the strength and broadens the application field of the block amorphous alloy.

When etching is performed with respect to a silicon-containing material by using a dry etching apparatus having a dual power source, the application of bias power is initiated before oxidization proceeds at a surface of the silicon-containing material. Specifically, the application of the bias power is initiated before the application of source power is initiated. Alternatively, the source power and the bias power are applied such that the effective value of the source power reaches a second predetermined value after the effective value of the bias power reaches a first predetermined value.

The invention belongs to the technical field of perovskite photovoltaic single crystal thin film composite materials, and particularly relates to a method for continuously preparing a perovskite photovoltaic single crystal thin film composite material. The method comprises the following steps: (1) dissolving CH3NH3I and PbI2 in an organic solvent dimethyl formamide (DMF), performing stirring at alow speed, performing aging at room temperature, further performing heating to remove the organic solvent dimethyl formamide (DMF), and performing standing in a nitrogen atmosphere for more than 2 days to obtain CH3NH3PbI3 nano microcrystal grains for later use; (2) preparing a compact layer; (3) preparing a micro-film layer; and (4) preparing a CH3NH3PbI3 perovskite single crystal thin sheet so as to obtain the perovskite photovoltaic single crystal thin film composite material. According to the invention, the defects of a perovskite layer are reduced, the surface states of crystal grains, crystal boundaries, pores and the like are reduced, and the stability of a perovskite solar cell is improved.