6 results about "Crystal growth" patented technology

The invention discloses a seeding mold for growing silicon crystals by using an orientated solidification method and a crystal growing method. The seeding mold is arranged at the internal bottom of a quartz crucible and comprises a seed crystal container and a sealing liquid container, wherein the sealing liquid container consists of cavities connected to the periphery of the seed crystal container and is used for accommodating a sealing substance; and the seed crystal container is provided with a first cavity for accommodating seed crystals. A method for growing monocrystalline silicon/similar monocrystalline silicon by adopting the seeding mold comprises the following steps of: arranging or setting the seeding mold at the bottom of the quartz crucible; arranging the sealing substance and the seed crystals in the sealing liquid container and the seed crystal container respectively; putting a silicon raw material into the quartz crucible; and growing monocrystals/similar monocrystals by adopting orientated solidification. By adopting the seeding mold and the crystal growing method, the problem of placement of the seed crystals can be solved without changing the structures of the conventional orientated solidification and quartz crucible, dislocation of the seed crystals in the seeding process is eliminated, and the spontaneous nucleation phenomenon of melt from the bottom wallface of the crucible is avoided. The seeding mold has low cost and is easy to process.

The invention relates to a multi-quantum well photovoltaic battery based on a nanometer graphite electron transmission layer, and a preparation method thereof. The battery comprises a front electrode, an anti-reflection layer, N-type silicon, P-type silicon and a back electrode, wherein a composite layer composed of graphite and semiconductor quantum dots is arranged between the anti-reflection layer and the N-type silicon. Compared to the prior art, the method is characterized in such a way that a sol method is employed, first of all, a semiconductor quantum dot colloid is prepared; under the effect of a surfactant, the graphite is uniformly dispersed to the colloid, and then, by taking the graphite as a crystal growth liquid, a uniform an ordered electron transmission layer and a semiconductor quantum dot layer are grown on the surface of a crystal silicon chip in a deposition mode. According to the invention, by use of a quantum dot impact ionization effect and a namometer effect and excellent electron separate transmission performance of nanometer graphite, the minority carrier life and the quantum efficiency of the photovoltaic battery are improved, and the nanometer graphite can improve separation and collection of electrons by the silicon solar battery, improves photoelectric currents and accordingly improve the conversion efficiency of the silicon solar battery.

The invention related to a preparation method of a silicon carbide microcrystalline homogenized in dimension and shaped in a polyhedron form. The preparation method comprises the following steps of: putting the SiC raw material in a crucible, fastening a microcrystalline depositing collector at the inner side of a crucible cover, screwing the crucible and then putting the crucible in a crystal growth furnace; vacuumizing the crystal growth system until the vacuum degree is less than 5*10<-3>Pa, and then filling an atmosphere gas of 1-20000Pa; increasing the temperature of the crystal growth system so that the temperature of the raw material zone is in the range from 1800 to 2200 DEG C, keeping the temperature of the microcrystalline depositing collector at the crucible cover in the range from 1750 to 2100 DEG C, and starting microcrystalline growing; and after the microcrystalline grows for 0.5-2 hours, turning off the power of the crystal growth furnace. The preparation method provided by the invention is not involved with any other precursor and catalyst; besides, the raw material zone is separated from the deposition growth zone; the obtained SiC microcrystalline dimension is adjustable in the range from 10 to 50 microns; the microcrystalline obtained is separated from each other and shaped in the polyhedron form; the microcrystalline growth period is short, and the microcrystalline growth method is simple and easy to popularize; therefore, the preparation method of the silicon carbide microcrystalline homogenized in dimension and shaped in the polyhedron form is suitable for large-scale industrial production and has high practicable value.

The invention discloses a method and a device for improving SiC crystal growth efficiency and quality. The method comprises the steps: obtaining gaseous Si through liquid Si; introducing gaseous CH4, cracking CH4 at a set temperature, then reacting with gaseous Si, pulling and rotating the seed crystal in a protective gas atmosphere to realize regulation and control and stabilization of a thermal field before growth of the SiC crystal and growth of a large-mass SiC single crystal so as to obtain the SiC crystal ingot. The device is used for realizing the method and comprises a crucible isolating layer and a heating unit, an isolation unit is arranged in the crucible, a first outlet is formed in the isolation unit, a first inlet connected with a first gas source is formed above the isolation unit, a second outlet connected with a gas treatment unit is formed above the crucible, a seed crystal rotating and lifting unit is arranged at the top in the crucible, and seed crystals are arranged below the seed crystal rotating and lifting unit; and the laser beams are additionally arranged so that regulation and control of the thermal field at the front edge of crystal growth are provided, and optimization of the radial growth uniformity of the crystal and adjustment of the axial temperature gradient are facilitated.