The method of preparing a quartz crucible coatings

The invention provides a method for preparing a quartz crucible coating. The method comprises the following steps of: (a) preparing a barium hydroxide solution, wherein the weight ratio of barium hydroxide to water in the barium hydroxide solution is 1:(46-52); and (b) heating a quartz crucible till the temperature is above 200 DEG C, uniformly spraying the barium hydroxide solution on the inner wall and the upper opening of the quartz crucible, and forming a barium hydroxide coating on the inner wall and the upper opening of the quartz crucible after spraying. According to the method, the barium hydroxide formed on the surface of the crucible is reacted with carbon dioxide in air to form barium carbonate; when the quartz crucible is heated on a mono-crystal furnace, the barium carbonate is decomposed into barium oxide; the barium oxide is reacted with the quartz crucible to form barium metasilicate; a barium metasilicate layer can be used for protecting the quartz crucible; mono-crystal silicon can be prevented from reacting with the quartz crucible in a high-temperature drawing process; the service life and the long crystal yield of the quartz crucible are improved; furthermore,the intensity of the quartz crucible can also be increased; and the high-temperature softening phenomenon is reduced.