62results about How to "Reduce defect concentration" patented technology

A method for removing defects at high pressure and high temperature (HP/HT) or for relieving strain in a non-diamond crystal commences by providing a crystal, which contains defects, and a pressure medium. The crystal and the pressure medium are disposed in a high pressure cell and placed in a high pressure apparatus, for processing under reaction conditions of sufficiently high pressure and high temperature for a time adequate for one or more of removing defects or relieving strain in the single crystal.

The invention discloses a formulation of an AC zinc oxide resistance chip. The formulation is characterized by comprising the following additives and a main material ZnO by weight percentage: 4.0 to 4.9 percent of Bi2O3, 3.0 to 4.0 percent of Sb2O3, 0.5 to 1.0 percent of SiO2, 2.0 to 3.0 percent of Co2O3, 0.50 to 0.80 percent of Cr2O3, 0.50 to 0.80 percent of MnCO3, 0.70 to 0.90 percent of NiO, 0.03 to 0.05 percent of aluminum nitrate, 0.10 to 0.20 percent of glass dust, 0.07 to 0.10 percent of B2O3 and 85.0 to 88.0 percent of ZnO. The formulation of the resistance chip has the following characteristics and advantages: the nickel protoxide and the glass dust are introduced into the formulation, so that the stability and the aging performance of the internal structure of the resistance chip is more excellent; and 2, dosage of cobalt sesquioxide, dibismuth trioxide and diantimony trioxide are added in the formulation, the mixture ratio of each composition is more reasonable, and the non-linearity coefficient of the resistance chip can be improved, the pressure ratio is reduced, the circulation capability is improved, and the comprehensive performance is excellent.

A method and apparatus for the unusually high rate deposition of thin film materials on a stationary or continuous substrate. The method includes delivery of a pre-selected precursor intermediate to a deposition chamber and formation of a thin film material from the intermediate. The intermediate is formed outside of the deposition chamber and includes a metastable species such as a free radical. The intermediate is pre-selected to include a metastable species conducive to the formation of a thin film material having a low defect concentration. By forming a low defect concentration material, deposition rate is decoupled from material quality and heretofore unprecedented deposition rates are achieved. In one embodiment, the pre-selected precursor intermediate is SiH₃. The method further includes combining the pre-selected precursor intermediate with a carrier gas, preferably in a deactivated state, where the carrier gas directs the transport of the pre-selected precursor intermediate to a substrate for deposition of the thin film material.

The maximum value of peak intensities of cathode luminescence of a wavelength corresponding to a band gap of gallium nitride and in a measured visual field of 0.1 mm×0.1 mm is 140 percent or higher of an average value of the peak intensities of the cathode luminescence, provided that the peak intensities of the cathode luminescence are measured on a surface of the gallium nitride substrate.

A solution-stirring top-seeded solution-growth method for forming CLBO of the type where water is added to a precursor mixture, where heavy water is substituted for the water.

A method and apparatus for forming thin film materials via a plasma deposition process in the presence of a magnetic field. A precursor is delivered to a deposition chamber and activated to form a plasma. The plasma may be initiated in the presence of a magnetic field or subjected to a magnetic field after initiation. The plasma includes ionized and neutral species derived from the precursor and the magnetic field manipulates the plasma to effect a reduction in the population of ionized species and an enhancement of the population of neutral species. A thin film material is subsequently formed from the resulting neutral-enriched deposition medium. The method permits formation of thin film materials having a low density of defects. In one embodiment, the thin film material is a photovoltaic material and the suppression of defects leads to an enhancement in photovoltaic efficiency.

The invention discloses a silicon-based chip with a mid-infrared spectrum signal enhancement function. The silicon-based chip comprises a silicon substrate, wherein the silicon substrate is sequentially provided with a Ge buffer layer and a heavily-doped Ge layer; and a sub-wavelength microstructure array is etched on the heavily-doped Ge layer. The invention further discloses a preparation methodof the silicon-based chip with the mid-infrared spectrum signal enhancement function. Compared with a III-V group semiconductor, the silicon-based chip with the mid-infrared spectrum signal enhancement function has weak lattice absorption characteristics, and is more suitable for being used as a molecular sensor chip material; and silicon is used as a substrate, so that the silicon-based chip canbe integrated with an electronic device in a monolithic integration mode conveniently, thereby highly improving stability and the yield of the device.

The invention relates to a sodium-ion battery carbon negative electrode material prepared based on waste wood chips and a preparation method thereof. Waste wood chips are used as a biomass carbon source and subjected to pre-carbonization and low-heating-rate high-temperature carbonization treatment, metal heteroatoms are removed by washing with an acid pickling solution, and drying is performed to obtain a hard carbon sodium-ion battery negative electrode material. The waste wood chips are used as a biomass raw material, a large amount of chips generated in the production process of wood products can be fully utilized, and the material has the advantages of being environmentally friendly, low in cost and the like. A low-carbonization heating rate pyrolysis method is adopted, so that the effects of reducing defect concentration, increasing interlayer spacing and improving graphitization degree are achieved, and the electrochemical performance of the material is effectively improved. The hard carbon negative electrode material prepared by the method has relatively high first coulombic efficiency and reversible specific capacity, shows excellent cycling stability and rate capability, and is an ideal sodium-ion battery negative electrode material.

A layered thin film device, such as a MTJ (Magnetic Tunnel Junction) device can be customized in shape by sequentially forming its successive layers over a symmetrically curved electrode. By initially shaping the electrode to have a concave or convex surface, the sequentially formed layers conform to that shape and acquire it and are subject to stresses that cause various crystal defects to migrate away from the axis of symmetry, leaving the region immediately surrounding the axis of symmetry relatively defect free. The resulting stack can then be patterned to leave only the region that is relatively defect free.

The invention provides a method for growing an InP base InAs quantum well. The method comprise the steps of growing an InP buffering layer on an InP substrate, growing an InAs quantum well structure on the InP buffering layer, and growing an InP cover layer on the InAs quantum well structure, wherein In[1-x]Ga[x]As stress gradation barrier layers are formed on the two sides of the InAs quantum well structure. According to the method, the In[1-x]Ga[x]As stress gradation barrier layers with gradual lattice constant are introduced on the two sides of the InAs quantum well to decelerate compression strain suffered by the InAs quantum well; defect concentrations in materials, which are produced due to the accumulated release of the strain, are reduced; the crystal quality of the InAs quantum well materials is improved; and luminous wavelengths of the InAs quantum well materials are extended.

The invention discloses a composite encapsulating material with high heat conduction activity and a preparation method thereof, and belongs to the field of metal based composite materials. The composite material consists of SnAg4Ti4 alloy powder, aluminum powder and diamond particle reinforcer, wherein volume percentage of diamond particles is 50%-70%, volume percentage of aluminum powder is 25%-49%, and volume percentage of SnAg4Ti4T alloy powder is 1%-5%. A preparation method for the composite encapsulating material comprises the following steps: preparing active brazing filler metal SnAg4Ti4 alloy powder through a vacuum gas-atomization powdering furnace, mechanically mixing powder, and putting mixed powder into a discharge plasma sintering furnace to prepare a diamond/aluminum composite material. The sintered composite material is relatively good in interface bonding, is relatively high in compactness, has heat conductivity of 703W/m.K, has a thermal expansion coefficient reduced to 7.9*10<-6>/K, and has compactness of 97.8% or more. The preparation method is strong in operability, is simple in process, and can be used for the fields of electronic encapsulating and the like.

The present invention provides a method for manufacturing a semiconductor substrate, comprising the step of: forming a first buffer Si layer on a substrate having a silicon surface; epitaxially growing, in sequence, a first strained SiGe layer and a first Si layer above the first buffer Si layer; implanting ions into the resulting substrate followed by annealing so as to relax the lattice of the first strained SiGe layer and to thereby providing tensile strain in the first Si layer and so that tensile strain is provided in the first Si layer; and epitaxially growing, in sequence, a second buffer Si layer and a second SiGe layer above the resulting substrate; and forming a second Si layer having tensile strain on the second SiGe layer.

The invention provides a manufacturing method of a fast recovery diode. The manufacturing method of the fast recovery diode comprises following steps: providing an N-type substrate with an N-type epitaxial layer; forming a device front structure at one side, far from the N-type substrate, of the N-type epitaxial layer; forming a platinum absorption structure on the surface, far from the N-type epitaxial layer, of the N-type substrate and forming a platinum material layer on the surface, far from the N-type epitaxial layer, of the device front structure; performing thermal diffusion to diffuseplatinum in the platinum material layer to the internal part of a device; removing the remaining platinum material layer and an oxide formed by thermal diffusion, performing thermal oxidation, and forming a sacrifice oxide layer on the surface, far from the N-type epitaxial layer, of the device front structure; loading a forward electric field to the device with the sacrifice oxide layer, whereinthe sacrifice oxide layer is connected with a positive voltage of the forward electric field, and the platinum absorption structure is connected with a negative voltage of the forward electric field;and removing the sacrifice oxide layer and the platinum absorption structure.

Method for making thin crystalline or polycrystalline layers. The method includes electrochemically etching a crystalline silicon template to form a porous double layer thereon, the double layer including a highly porous deeper layer and a less porous shallower layer. The shallower layer is irradiated with a short laser pulse selected to recrystallize the shallower layer resulting in a crystalline layer. Silicon is deposited on the recrystallized shallower layer and the silicon is irradiated with a short laser pulse selected to crystalize the silicon leaving a layer of crystallized silicon on the template. Thereafter, the layer of crystallized silicon is separated from the template. The process of the invention can be used to make optoelectronic devices.

The crystallization system includes a crucible provided with a bottom and with side walls designed to contain the material to be solidified and a device for creating a main thermal gradient inside the crucible in a perpendicular direction to the bottom of the crucible. An additional inductive heating device is arranged at the level of the side walls of the crucible facing the liquid material and without overlapping with the solid phase. This additional inductive heating device is configured to heat a part of the crystalline material located in the vicinity of the triple contact line between the liquid material, the solidified material and the crucible so that the interface between the liquid material and the solidified material forms a convex meniscus in the vicinity of the triple contact line.

The invention discloses a platinum doping method of a fast recovery diode in the technical field of semiconductor power devices. The platinum doping method comprises the following steps: growing an oxide layer on the front surface of an N-type silicon substrate; forming a doping window on the oxide layer and injecting boron ions to form a P-type doping region, then performing annealing treatment, and forming a thin oxide layer on the surface of the P-type doping region after annealing; forming a contact hole of a front electrode on the thin oxide layer; depositing polycrystalline silicon on the front surface of the oxide layer to form a polycrystalline silicon layer, wherein the polycrystalline silicon is in contact with the P-type doped region through a contact hole; and sputtering or evaporating a platinum metal layer on the back surface of the N-type silicon substrate. The diode chip prepared by the method has shorter turn-off time, smaller reverse overshoot current and higher softness; meanwhile, the electric leakage possibility of the chip is reduced, and the reliability of the chip is improved.

The invention discloses a crystalline silicon solar cell without an Ag main grid line and a manufacturing process therefor. The crystalline silicon solar cell comprises a solar cell body, wherein the solar cell body comprises a light-receiving surface and a backlight surface; multiple light-receiving surface main grid lines and multiple light-receiving surface secondary grid lines are arranged on the light-receiving surface of the solar cell body; the light-receiving surface main grid lines and the light-receiving surface secondary grid lines are arranged in a perpendicular manner mutually; multiple backlight surface main grid lines are arranged on the backlight surface of the solar cell body; the light-receiving surface main grid lines and the backlight surface main grid lines are all manufactured by first conductive solder strips; and the light-receiving surface secondary grid lines are Ag secondary grid lines. The crystalline silicon solar cell without the Ag main grid line and the manufacturing process therefor have the beneficial effects that the Ag slurry consumption is greatly reduced, the cost is lowered, a sintering area between Ag and silicon is reduced, the defect concentration is lowered, and the conversion efficiency is improved; multiple main grid lines can be designed, so that the battery conversion efficiency is further improved; and quantity production can be realized, and the production cost is low.

The invention discloses an irradiation resistance nano-porous membrane, and belongs to the application field of advanced nuclear energy materials. The irradiation resistance nano-porous membrane comprises longitudinal nano-hole channels penetrating through the surface, the diameter of each longitudinal nano-hole channel is larger than 2 nanometers, the distance between every two adjacent longitudinal nano-hole channels is smaller than the scattering distance of interstitial atoms and the He gas, and branch-shaped nano-hole channels are transversely formed in each longitudinal nano-hole channel. The abundant hole channels of the nano-porous membrane can absorb the interstitial atoms, vacancies, transmutation gas and other flaws produced by irradiation and can also release gas atoms out of a material, the flaw content inside the material can be greatly reduced, the interstitial atoms, the vacancies and the transmutation gas are prevented from being gathered to form an atomic cluster, a cavity, bubbles and the like, and the radiation swelling resisting capability, the hardening resisting capability and the non-crystallizing capability of the material are greatly improved.