Shin-Etsu Handotai Co., Ltd.

Makoto Suzuki

Tatsuo Abe

Kazuya Tomii

Kazutoshi Mizushima

Nakaji Miura

Yasuhiro Sekine

In a process for polishing the chamfered peripheral part of a wafer using a polishing cloth while supplying a polishing slurry in order to improve productivity of the process by reducing a polishing time, at least two steps of polishing processes are performed in sequence. The process comprises a first polishing process to polish a particular part, e.g. the part corresponding to the {110} plane of a peripheral part of the wafer and a second polishing process in which the whole part of a peripheral part of the wafer is polished for finishing by means of varying a hardness of the polishing clothes and/or a particle size of abrasives in the slurry such as the hardness of the polishing cloth in the second polishing process being softer than that of in the first polishing process and a particle size of abrasives in the slurry in the second polishing process being finer than that of in the first polishing process.

Method for apparatus for polishing outer peripheral chamfered part of wafer

According to the invention, a plurality of wafers are disposed in a steady-state rotating flow of a mixed acid in a main chemical processing zone in an etching trough, the rotating flow being formed to be substantially concentric circle with the wafers, thus permitting uniform dispersion of air bubbles for bubbling in the mixed acid and stable flow thereof to obtain reliable reproduction of satisfactory flatness and luster. A flow of mixed acid in the etching trough is formed as a superficial horizontal laminar flow in the neighborhood of the liquid level and a rotating flow induced in the neighborhood of the semiconductor wafer. Mixed acid in the etching trough is caused to overflow from the mixed acid supply side to the opposite side and is thus discharged.

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Fukushima, Japan

Makoto Suzuki