13 results about "Nanocrystalline diamond" patented technology

According to the silicon carbide / diamond multi-layer composite film and the preparation method thereof, a polycrystalline silicon carbide matrix in the multi-layer composite film is a bottom layer, and the multi-layer composite film has high strength, high rigidity, high heat conductivity and oxidation resistance; the components of the gradient SiC-C transition layer gradually change from pure SiC to rich C-SiC and then to diamond-like carbon, and the gradient SiC-C transition layer is used for slowly releasing thermal stress and enhancing binding force; the nanocrystalline diamond is used as the top layer and has high hardness, low friction coefficient, particle scouring resistance and high infrared transmittance; the silicon carbide / diamond multi-layer composite film is obtained through a chemical vapor deposition method, the process is mature, and the silicon carbide / diamond multi-layer composite film has good heat conduction performance and infrared transmittance and is suitable for infrared guidance systems with extremely severe working environments, such as optical materials of fairings, optical windows and the like.

The invention belongs to the technical field of hard alloy cutter coatings, and particularly relates to a gradient diamond film and a preparation method and application thereof. A hard alloy substrate is subjected to ultrasonic seeding through diamond suspension liquid, then the gradient diamond film is prepared through sectional type chemical vapor deposition, and the gradient diamond film comprises a nanocrystalline diamond film layer and a boron-doped microcrystalline diamond film layer which are sequentially arranged in a stacked mode. The sectional type chemical vapor deposition comprises first-stage deposition and second-stage deposition which are carried out in sequence. According to the preparation method provided by the invention, through dynamic coupling of air pressure, temperature and gas flow and design of the gradient diamond film, the core problem of'uneven gradient structure-concentrated interface stress' in the prior art is solved, and a technical support is provided for engineering application of a high-end tool coating.

Embodiments include a modular high frequency emission source for the growth of low roughness nanocrystalline diamond films. In one embodiment, a method of manufacturing a nanocrystal diamond (NCD) film includes loading a nanodiamond seed silicon wafer or a bare silicon wafer that has been surface treated and incubated into a microwave plasma enhanced chemical vapor deposition (MWPECVD) chamber, and treating the nanodiamond seed silicon wafer or the bare silicon wafer that has been surface treated and incubated with a plasma of CxHy (y > = x), CO2, and H2 at a power greater than 50 W to form a nanocrystalline diamond layer thereon.

The invention relates to the field of medical instruments, in particular to a nano diamond-like film intravascular stent and a preparation method thereof.The preparation method comprises the following steps that firstly, a base material is pretreated, then the nano diamond-like film stent is prepared through a plasma enhanced chemical vapor deposition technology, and after an equipment reaction chamber is adjusted to be in a vacuum state, the nano diamond-like film intravascular stent is prepared under argon protection; the method comprises the following steps: inputting benzene into a vacuum reaction chamber of direct-current arc discharge plasma, introducing silane gas at the same time, bombarding the generated plasma to a negative voltage cathode, and forming a diamond-like carbon film containing a silicon element on the surface when the plasma passes through a substrate material support sample, the silicon element content in the diamond-like carbon film being 15-45%; the silicon element is mainly added to form the elastic concentration gradient type diamond-like carbon film stent, so that the adhesive force, toughness, tensile strength and other physical properties of the coating are improved, the stent has good biocompatibility, and later thrombosis and restenosis after stent implantation are avoided.

The invention provides a nanocrystalline diamond heterojunction ultraviolet photoelectric detector, which is characterized in that seed crystal pretreatment is carried out on monocrystalline silicon, the obtained seed crystal monocrystalline silicon is used as a substrate, acetone is used as a carbon source, boron-doped nanocrystalline diamond is grown on the surface of the substrate by using a hot filament chemical vapor deposition method, the boron-doped nanocrystalline diamond is placed in a sulfuric acid solution, and the boron-doped nanocrystalline diamond heterojunction ultraviolet photoelectric detector is obtained. And performing cyclic voltammetry treatment. Then, the titanium source precursor is partially covered and placed in atomic layer deposition equipment, and deposition circulation is conducted through the titanium source precursor; and finally, the diamond and Ti areas are coated with silver paste to form an ohmic contact electrode, and the prepared nanocrystalline diamond heterojunction ultraviolet photoelectric detector has excellent response speed, can better adapt to high-speed ultraviolet detection tasks and shows good application prospects in the fields of ultraviolet communication, rapid switch monitoring and the like.

The application discloses a kind of photoelectric parameter test methods of LED epitaxial wafer, it is related to photoelectric testing technical field, boron-doped nanocrystalline diamond composite probe of micro-nano hierarchical cauliflower texture is contacted with LED epitaxial wafer and is carried out electrical parameter test;The preparation method of probe includes the following steps: substrate sharpening, gradient buffer layer deposition and carbon injection locking, electrostatic adsorption planting, pulse modulation MPCVD growth, in-situ fluorination end-capping post-processing.The composite probe is used by the application through structure optimization and surface modification, realizes low damage, high stable electrical contact, solves the problem of thermal spalling and impurity adhesion of probe in high-frequency test, significantly prolongs the service life of probe, and improves the accuracy of test data and the consistency of yield grading.

The invention discloses a polishing method of nano polycrystalline diamond, which comprises the following steps: selecting a proper polishing process according to different initial roughness through a staged and grid structure polishing strategy, and when Ra is greater than or equal to 100nm, adopting three stages of grinding, rough polishing and fine polishing; when 40 nm is less than or equal to Rult; when the wavelength is 100 nm, a rough polishing stage and a fine polishing stage are adopted; when 10 nm is less than or equal to Rult; and when the wavelength is 40 nm, only the fine polishing stage is carried out. According to the method, the surface roughness Ra of the nano polycrystalline diamond is reduced to be smaller than or equal to 5 nm, and meanwhile the high removal rate and the low surface defect density are guaranteed. The method is particularly suitable for high-precision application fields such as optical windows, micro-nano cutters and high-pressure anvil cells.

The application discloses a flexible self-supporting diamond heat dissipation film and a preparation method thereof, and relates to the technical field of heat dissipation materials. In view of the problems of high heat flow density of power devices, 5G radio frequency and advanced packaging chips, strong anisotropy of traditional graphite films, poor insulation of metal foils, and easy aging and pumping out of silicone grease / gaskets to cause the increase of interface thermal resistance, the application provides the flexible self-supporting diamond heat dissipation film and the preparation method thereof. On the structure, 10-50 mu m nanocrystalline CVD diamond film is used as the main body, and 1-3 mu m polyimide surface modification layers are arranged on both sides to improve wet adhesion and environmental resistance. On the process, after the silicon substrate is cleaned and activated, a composite is formed through CVD deposition, self-supporting film is obtained by using the internal stress of the difference in thermal expansion of diamond / silicon, and the PI layer is coated and solidified on both sides. As a result, the flexible self-supporting diamond heat dissipation film has high thermal conductivity, thin and light weight, and can be repeatedly bent and mounted, reduces the interface thermal resistance, and improves the long-term heat dissipation reliability.

A method for depositing nanocrystalline diamond films is described. This method may be used in the manufacture of integrated circuits. The method includes treating a substrate with plasma to form a treated substrate surface, incubating the treated substrate with a carbon-rich plasma to nucleate diamond particles on the treated substrate surface, and then treating the substrate with plasma to form a nanocrystalline diamond film. The resulting nanocrystalline diamond film is formed on an oxide-rich amorphous layer at the interface between the nanocrystalline diamond film and the silicon substrate.

A method for growing nanocrystalline diamond (NCD) on Ga2O3 to provide thermal management in Ga2O3-based devices. A protective SiNx interlayer is deposited on the Ga2O3 before growth of the NCD layer to protect the Ga2O3 from damage caused during growth of the NCD layer. The presence of the NCD provides thermal management and enables improved performance of the Ga2O3-based device.

The invention discloses a carbon nanotube-nano polycrystalline diamond composite material and a preparation method thereof. The raw materials comprise carbon nanotubes and carbon nano scallions, the OLC is prepared from detonation method nano-diamond with the average particle size of 5 nm through vacuum annealing at the temperature of 800-1800 DEG C, and the OLC contains a diamond crystal core, a diamond structure core and a complete structure; and the CNT is of a graphite curled tubular structure with the tube diameter of 4-8nm and the length of 0.5-2mu m. The preparation method comprises the following steps: ultrasonically dispersing and drying CNT with ethanol, mixing with OLC, pre-pressing for 30-60 seconds under 400-600 MPa, filling a mold according to a specific mold assembly process, preserving heat for 5-60 minutes under the conditions of 7-25 GPa and 1800-2200 DEG C, sintering at high temperature and high pressure, and grinding and deburring a blank to obtain a finished product. The closed spherical structure formed by CNT fracture is used for balancing the internal pressure loss of the sintered body, the OLC sintering condition is remarkably reduced, the Vickers hardness of the product reaches 17-202 GPa, and the method has high hardness and preparation feasibility and can be widely applied to the fields of aerospace, gem processing, petroleum drilling and the like.

The invention discloses a binder-free nano polycrystalline diamond and a preparation method thereof, the raw material of the binder-free nano polycrystalline diamond is nano diamond (ND), and the average particle size of the ND is 5nm. During preparation, the ND raw material is filled into a hard alloy mold to be pre-pressed, the pre-pressing pressure is 400-600 MPa, and the pre-pressing time is 30-60 s. And then, the pre-pressed sample is put into a mold for high-temperature and high-pressure sintering. The sintering pressure ranges from 7 GPa to 25 GPa, the sintering temperature ranges from 1600 DEG C to 2250 DEG C, the heat preservation time ranges from 5 min to 60 min, then cooling and pressure relief are conducted, and the binder-free polycrystalline diamond is prepared. By utilizing the characteristics that ND has a large number of surface dangling bonds and meets the basic principle of solid reaction, the sintering condition is reduced, a binding agent in the sintering process is removed, and the binding-agent-free nano polycrystalline diamond is formed.

The application relates to a device and a method for synthesizing nanometer polycrystal diamond powder based on liquid-phase pulse discharge reflection converging shock waves, and belongs to the technical field of nanometer diamond preparation processes. Carbon material powder is mixed with distilled water to form a suspension, high temperature and high pressure generated by liquid-phase pulse discharge are used to make the carbon source material phase change and synthesize nanometer diamond, the pressure of the discharge shock wave is adjusted by adjusting the electrode spacing and the charging voltage, and then the yield of the diamond is controlled, and the obtained product has high crystallinity and uniform particle size distribution.