9results about How to "Improve doping uniformity" patented technology

The invention discloses a growth method of a high-uniformity Ga-doped YIG single crystal material, and belongs to the technical field of ferrite single crystal materials.According to the method, a garnet Y3Fe (5-x) GaxO12 single crystal is grown through a high-temperature and high-pressure optical floating zone method, compared with a traditional fluxing agent method, the method can effectively avoid the influence of the element segregation phenomenon on doping uniformity, and the doping uniformity of the garnet Y3Fe (5-x) GaxO12 single crystal is improved. The prepared Y3Fe5-xGaxO12 single crystal material has good doping uniformity, high saturation magnetization consistency and almost no gradient distribution, and can be applied to YIG oscillators and magneto-optical isolators with high requirements on the quality of the single crystal material.

The invention discloses a Y0. 4Sr0. 6MnO3 perovskite porous loading material as well as a synthesis method and application thereof, and belongs to the field of cracking CO2 fuel synthesis catalyst materials. The invention aims to solve the problems of low stability, low CO yield and low CO2 conversion rate of a catalytic material in a solar thermochemical fuel preparation process (two-step CO2 catalytic cracking). The method comprises the following steps: mixing EDTA (Ethylene Diamine Tetraacetic Acid) with an ammonia water solution, adding deionized water, heating in a water bath, and magnetically stirring; adding Y (NO3) 3.6 H2O, Mn (NO3) 2.4 H2O and Sr (NO3) 2 powder, and then adding citric acid monohydrate; adding ammonia water to adjust the pH value, and keeping heating and stirring; drying, grinding, calcining, then grinding, mixing with deionized water, dropwise attaching turbid liquid to the SiC porous framework, and purging; and drying. According to the preparation method, the Y0. 4Sr0. 6MnO3 powder material is attached to the SiC porous framework, so that the gas-solid reaction contact area of the powder material and CO2 is increased, and the oxidation-reduction reaction rate is increased; the heating rate of the material is accelerated, and the photo-thermal conversion efficiency and the overall efficiency are improved.

This invention discloses the preparation and application of core-shell structured hollow glass microsphere precursor particles, comprising: mixing water glass with water, then removing sodium ions with a cation exchange resin to obtain a silicate aqueous solution; dissolving metal nitrate and boric acid into a saturated aqueous solution, adding it to the silicate aqueous solution under magnetic stirring to obtain a uniformly doped transparent mixed solution, and spray drying to obtain core-shell structured hollow glass microsphere precursor particles. This invention pre-forms relatively large pores within the precursor particles to obtain core-shell structured hollow glass microsphere precursor particles, which can effectively shorten the foaming and spheroidizing time, reduce incompletely foamed particles, and improve the yield and performance of hollow glass microspheres. This invention uses molecular-level water glass as the main raw material, completing part of the silicate formation and cross-linking reaction during the process, replacing the bonding and aggregation of particles prepared by traditional soft chemical methods with chemical bonding, thus enhancing the compressive strength of the precursor particles.

The invention provides a preparation method of carbonic acid system aluminum-doped cobaltosic oxide, which comprises the following steps: firstly, respectively preparing a cobalt salt solution, an ammonium bicarbonate solution and an aluminum salt solution; secondly, adding the solution into a reaction container containing a base solution in a parallel flow manner, and controlling the reaction temperature, the pH value of the system and the stirring rotating speed to obtain a first cobalt carbonate wet material; the first cobalt carbonate wet material enters a thickener through an overflow tank to be separated, and clear liquid and sediment are obtained; feeding the precipitate into the reaction container for continuous reaction, and controlling the growth speed of crystal grains to obtain a second cobalt carbonate wet material; and finally, washing, drying and calcining the second cobalt carbonate wet material to obtain the aluminum-doped cobaltosic oxide. The prepared product has the advantages of being good in sphericity degree, high in specific surface area and tap density, good in aluminum element doping uniformity and the like, the selected raw materials are common raw materials and are easy to obtain, the method is easy to operate, industrial production is easy, and the method has wide popularization and application prospects in lithium ion positive electrode materials.

This invention discloses a method for element doping of a thin-film solar cell and its absorber layer, relating to the field of thin-film solar cell technology. By immersing the activated absorber layer in a salt solution of a predetermined dopant element and simultaneously applying an exogenous inducing variable, the predetermined element is doped. During the doping process, the diffusion of dopant ions into the grain boundaries and lattice interior of the absorber layer is promoted, ensuring that the element is not affected by the surface morphology, hydrophilicity / hydrophobicity, internal or edge structure of the absorber layer. This solves the problems of difficult-to-control element doping uniformity, poor process stability, and low effective doping activation rate in existing technologies. It achieves the goal of diffusive doping of p-type elements in the absorber layer with high doping uniformity, high doping activation rate, controllable doping process, and compatibility with existing processes.

The present invention discloses a method for improving the passivation effect of a double-sided TOPCon cell. The method of the present invention comprises the following steps: polishing a silicon wafer; depositing a tunneling oxide layer and an intrinsic amorphous silicon layer on both sides of the polished silicon wafer; performing back-side boron diffusion on the silicon wafer after depositing the intrinsic amorphous silicon: performing front-side texturing; performing tunneling silicon oxide and n-poly on the front side of the silicon wafer; and then annealing; wherein, before the back-side boron diffusion, external oxidation is also included, and / or before the tunneling silicon oxide and n-poly, the front side of the silicon wafer after texturing is also included. The steps of pre-phosphorus diffusion and HF cleaning. The present invention reduces the boron diffusion rate by adding external oxidation before the boron diffusion, reduces the damage of boron to the tunneling silicon oxide, and can also perform pre-phosphorus diffusion before the tunneling silicon oxide and n-poly process to infiltrate phosphorus in advance, thereby reducing the damage to the tunneling silicon oxide when phosphorus enters the substrate, and synergistically improving the passivation effect.

The present invention provides a lightly doped substrate, a substrate with a selective emitter, a solar cell and a preparation method and application thereof. The lightly doped substrate comprises a P-type silicon wafer layer, an N-type silicon layer, a first phosphorus silicon glass layer, an oxide layer and a second phosphorus silicon glass layer which are connected in sequence. In the subsequent heavy doping process, the lightly doped substrate of the present invention can increase the doping uniformity of the doping source on the surface of the silicon wafer on the one hand, and can reduce the square resistance of the heavily doped area on the other hand, thereby reducing the silver silicon contact resistance. The preparation method of the lightly doped substrate is simple, easy to implement and suitable for large-scale industrial production and application. The heavily doped area in the substrate with a selective emitter prepared by the lightly doped substrate has a high phosphorus content, a low and uniform square resistance of the heavily doped area, and a high light conversion efficiency.

The invention discloses an automatic growth raw material adding device, an automatic growth raw material adding method and application. The automatic growth raw material adding device comprises a conveying channel, a first air chamber, a second air chamber and a third air chamber, the first gas chamber is used for accommodating first growth source gas; the second gas chamber is in heat conduction connection with the first gas chamber and is used for accommodating second growth source gas; the third gas chamber is adjacent to the first gas chamber, is communicated with the growth raw material storage chamber and is used for accommodating third gas; when the temperature of the second growth source gas is higher than that of the first growth source gas, the first gas chamber enters an expansion state and extrudes the third gas chamber, so that at least part of third gas in the third gas chamber enters the growth raw material storage chamber and applies pressure to the growth raw material in the growth raw material storage chamber; and then at least part of the growth raw materials are driven to be transferred into the at least two reaction chambers along the conveying channel. The growth raw materials can be automatically added in two different growth modes at the same time, and the method can be applied to the field of growth of gallium nitride or aluminum nitride substrates.

The invention relates to a low-junction capacitance symmetric transient voltage suppressor diode and a preparation method thereof. The preparation method comprises the steps of silicon wafer cleaning, N-type doping, oxidation, photoetching, oxide layer removal, slotting corrosion, passivation, surface corrosion, electrode manufacturing, metal stripping and cutting. Wherein in the N-type doping step, POCl3 is used as a gas-phase phosphorus source, double-sided synchronous diffusion is carried out on a silicon wafer, and a shallow junction N-type region with the junction depth of 1.5-3.0 microns is formed; in the oxidation step, the silicon wafer with the shallow junction N-type region is subjected to high-temperature oxidation in an oxygen-containing atmosphere, phosphorus atoms are driven to be redistributed from the surface to the inside, a doping section with the phosphorus concentration gradually changing from the surface of the silicon wafer to the inside is formed, and a surface oxidation layer is synchronously grown. According to the preparation method disclosed by the invention, the junction capacitance is reduced, and the symmetry, the response speed and the pulse endurance capability of the bidirectional transient voltage suppression diode are improved by improving the doping uniformity.