5results about How to "Improve fragmentation problem" patented technology

A method for solving the problem of broken pieces in the bonding process of Micro LED wafers belongs to the field of processing technology of semiconductor devices. The method first involves cleaning the substrate surface of a sapphire substrate GaN epitaxial wafer, then laser etching the substrate surface to obtain a deep groove with a periodic grating structure or a bull's eye ring structure, then growing a SiO2 layer on the substrate surface, spin-coating a positive photoresist and curing it, then performing mask exposure on the photoresist film in the deep groove, decomposing the exposed photoresist film to expose the SiO2 layer in the deep groove; after removing the SiO2 layer in the deep groove, Mg ion implantation is performed to obtain an ion implantation layer in the deep groove. The method of the present invention can effectively release substrate stress and reduce the hardness of the GaN epitaxial wafer so that it can better match the hardness of silicon-based CMOS, all of which effectively reduce the generation of broken pieces in the bonding process of Micro LED wafers.

The invention provides a gallium nitride power electronic device preparation method and a gallium nitride power electronic device, and relates to the technical field of semiconductors. The method comprises the following steps: bonding a reinforcing plate on the front surface of a prepared device; performing overall thinning processing on the substrate of the device from the back surface of the device so as to thin the substrate to a preset thickness range; processing heat dissipation holes in the back surface of the substrate; heat conduction materials are arranged on the back face of the substrate and in the heat dissipation holes, so that a heat conduction layer is formed on the back face of the substrate; and the bonding of the reinforcing plate is removed. According to the preparation method of the gallium nitride power electronic device, the substrate can be thinned, the problem that the substrate is broken can be avoided, and the heat dissipation capability of the device is enhanced by arranging the heat conduction layer, so that the performance and reliability of the device are improved.

The utility model discloses an asphalt rotary shear failure experimental device, and relates to the technical field of asphalt performance testing. The device comprises a test box body, a top panel, a heating cylinder, a fixed plate and a fixed disc, an embedded plate is movably connected in a movable opening, the fixed disc is fixed on the end face, flush with the test box body, of the embedded plate, the fixed plate is arranged on one side of the test box body, and electric push rods are symmetrically fixed on the side, close to the test box body, of the fixed plate along the center line in the vertical direction. The telescopic ends of the two electric push rods are fixed to the fixing disc, a top panel is hinged to the upper portion in the test box body, air outlets are symmetrically formed in the top of the top panel in a penetrating mode along the center line parallel to the short edge, and a heating cylinder is fixed to the center of the interior of the top panel in a penetrating mode. Through the arrangement of the test box body, the top panel, the heating cylinder, the fixed plate and the fixed disc, the problems that the asphalt rotary shear failure test device is easy to cause non-uniform temperature of asphalt and broken asphalt blocks after test are inconvenient to clean are solved.

This invention relates to the field of lithium battery material recycling technology, specifically to a method for recycling and utilizing cathode materials from retired lithium iron phosphate batteries. The recycled retired lithium iron phosphate battery cathode materials are crushed, and the fragments are soaked in a solvent with stirring. After filtration, the filter residue is repeatedly washed with deionized water and dried to obtain coarse powder of the recycled cathode material. The coarse powder is subjected to ICP testing, and lithium, iron, phosphorus, grinding aids, and anhydrous ethanol are added for wet ball milling. After ball milling, the powder is dried to obtain a precursor. The precursor is then sintered under a nitrogen atmosphere to obtain the lithium iron phosphate cathode material. This method for recycling retired lithium iron phosphate battery cathode materials is simple, environmentally friendly, and economically efficient. The recycled cathode material meets the requirements for use in the battery industry.

The invention belongs to the field of processing, and relates to a preparation method of a bicrystal test plate seed crystal, which comprises the following steps: preparing a seed crystal mother block with a specific crystal lattice orientation and an axisymmetric stereo structure from a single crystal raw material; averagely cutting the seed crystal mother block parallel to the symmetry axis of the seed crystal mother block to obtain two seed crystals with the same area and an uncut connecting region; applying a reverse moment to the seed crystals on the two sides of the connection area, breaking the connection area, and obtaining a group of specific fractures on the seed crystals on the two sides of the connection area; and randomly selecting one seed crystal from the mixed packaged and transported seed crystals, screening the other seed crystal which is uniquely matched with the fracture from the residual seed crystals based on the fracture, and pressing the two seed crystals to prepare the double-crystal test plate. The target seed crystal which is uniquely matched with the selected seed crystal and is from the same seed crystal mother block is screened out from a pile of mixed packaged and transported seed crystals, the lattice orientation of the two seed crystals is determined when the double-crystal test plate is prepared through pressing, and the problems that in the prior art, the lattice orientation of the two seed crystals is difficult to determine, and the two seed crystals are prone to inversion are solved.