1.
    发明专利
    未知

    公开(公告)号:DE2629709A1

    公开(公告)日:1978-01-05

    申请号:DE2629709

    申请日:1976-07-02

    Abstract: A method of making a metal-ion free silicon dioxide is provided which has a specifically uniform grain size and which is suitable for the mechanical polishing of semiconductor wafers. In the process according to the invention high grade silicon is dissolved in an aqueous solution of an organic amine. The base surplus is buffered by hydrogen ions from an added hydroxybenzene Subsequently, the solution is boiled under reflux for several hours with bubbling of purified air. The precipitated amorphous silicon dioxide is collected, rinsed, and suspended in water for the mechanical polishing of wafers.

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