2results about How to "Controlled reunion" patented technology

A megasonic auxiliary polishing device for a large-diameter gallium antimonide wafer relates to the technical field of wafer surface polishing and comprises a wafer carrier head, a polishing disc and a megasonic generator. The polishing solution containing device is arranged above the megasonic generator, a high-frequency oscillation signal sent by the megasonic generator is converted into high-frequency mechanical oscillation to be transmitted into the polishing solution, an agglomerated colloidal solution formed by an abrasive part in the polishing solution is scattered, aggregation of nanoscale micelles is inhibited, and then the uniform distribution of the polishing solution colloidal solution on the polishing disc is promoted. The consistency of the roughness of the surface of the wafer in the polishing process is high; the polishing disc is in a circular ring shape, the wafer carrying heads are evenly distributed on the circumference of the polishing disc, the portion, between the adjacent wafer carrying heads, of the polishing disc is provided with a washing cover, washing pipes are evenly arranged in the washing cover, and liquid discharged from the lower ends of the washing pipes washes the polishing disc to wash away scraps on the surface of the polishing disc. And an adverse influence factor on the polishing quality of the wafer is reduced by one, so that the controllability of the polishing quality is improved.

This application discloses a method for preparing high-purity electronic-grade titanium dioxide from ilmenite, belonging to the field of titanium dioxide preparation technology. The method includes steps such as raw material processing, concentrated sulfuric acid acidolysis, sedimentation and filtration, FeSO4 crystallization and separation, preparation of hydrated titanium dioxide, washing and bleaching of hydrated titanium dioxide, acidolysis of hydrated titanium dioxide, secondary hydrolysis, washing and filtration, and calcination. This method effectively removes various impurities such as iron, phosphorus, niobium, and zirconium through acidolysis, secondary hydrolysis, and multiple fine washing operations on the hydrated titanium dioxide intermediate. The resulting titanium dioxide product has a purity of over 99.9%, providing a new route for preparing high-purity electronic-grade titanium dioxide from ilmenite.