63results about How to "For subsequent cleaning" patented technology

The invention discloses an aqueous grinding fluid applied to super precision grinding of hard and brittle materials and an application method thereof. The grinding liquid contains chelant 0.1-5, a pH value regulator 5-15, a suspending agent 0.2-5, a dispersion stabilizer 0.5-10, a lubricant 5-20, an antirusting agent 0.5-5, fungicide 0-2, a defoamer 0-2 and deionized water compensating the balance of total amount of 100 parts. Under an alkali condition, the aqueous grinding fluid applied to super precision grinding of hard and brittle materials is beneficial for grinding materials with various sizes, has good suspension property and dispersion stability; when the aqueous grinding fluid is used for super precision grinding of various different hard and brittle materials, especially high-hardness materials, scratches, etching pits and other defects are not produced easily; and the grinding speed is high, the subsequent cleaning is convenient; and the aqueous grinding fluid has excellent lubricating property and antirusting property when in matched use with the grinding materials, and the mixing liquid is uniform in color and has no sediment in 48 h. When the aqueous grinding fluid is used for grinding a wafer on a grinding machine, the ground wafer is subjected to water-added ultrasonic washing, and the wafer has good surface smooth finish, no scales, etching pits and other defects, and the surface roughness can be within 2 microns.

The invention discloses a method for manufacturing polycrystalline silicon solar cells with selective emitters. The method includes steps of (1), cleaning silicon wafers and etching textures of the silicon wafers; (2), growing active doping agents; (3), placing the silicon wafers in a diffusion furnace and cooling the diffusion furnace until the temperature of the diffusion furnace ranges from 500 DEG C to 550 DEG C; (4), feeding N<2> and O<2> into the diffusion furnace to perform oxidization after the temperature of the diffusion furnace is stable; (5), heating the diffusion furnace at the speed ranging from 5 DEG C / min to 10 DEG C / min until the temperature of the diffusion furnace ranges from 850 DEG C to 870 DEG C and feeding gas with a phosphorus source into the diffusion furnace to perform diffusion after the temperature of the diffusion furnace is stable; (6), keeping the temperature of the diffusion furnace unchanged, feeding N<2> and O<2> into the diffusion furnace to perform constant-temperature propulsion; (7), cooling and discharging; and (8), cleaning, etching, removing edges, coating anti-reflection films, performing screen printing and sintering so as to obtain the polycrystalline silicon solar cells with the selective emitters. The novel method for manufacturing the polycrystalline silicon solar cells with the selective emitters has the advantages that the manufacturing cost is low, the manufacturing time is short, and the method is compatible to an existing standard cell process and has an industrialization prospect.