APPARATUS FOR MEASURING INTERVAL BETWEEN WAFER AND ELECTRODE

摘要

PURPOSE: An apparatus for measuring an interval between a wafer and an electrode is provided to reduce time wasted for cleaning a chamber by automatically carrying out a periodical interval measurement so that the chamber is not opened, and to correct a difference between data obtained from interval measurement and a reference value by performing a periodical interval measurement when necessary. CONSTITUTION: A disc of a wafer size is transferred and ejected to/from a chamber by a robot arm. A tool for measuring an interval is formed between a central portion and an edge portion of the disc to measure the interval between a wafer and an electrode. The size of the disc is smaller than the wafer size.