| 摘要 |
<p>A semiconductor wafer (W) is mounted on top of a mounting stand (3) within a vacuum vessel of a vacuum processing apparatus such as a vacuum film-formation apparatus or an etching apparatus for semiconductor wafers. A heat-transfer gas such as helium is supplied to a gap between the wafer and the mounting stand, and film-formation or etching is performed while the wafer is held at a predetermined temperature. To ensure a simple and reliable detection of any leakage of the helium from between the wafer and the mounting stand during this process because of an abnormal state, the surface of a dielectric material such as aluminum nitride that configures the mounting stand (3) is given a mirror finish and the wafer (W) is attracted to the surface of the mounting stand (3) by an attractive force of at least 1 kg/cm<2>, whereby the helium from the gas supply path (5) is sealed in on the rear surface side of the wafer (W). A flowmeter (54) is provided in the gas supply path (5), a flowrate measured by this flowmeter is compared by a comparator (6) against a threshold value, which corresponds to a flowrate that occurs when a leakage is generated between the rear surface side of the wafer (W) and the surface of the mounting stand (3) in a normal state, and an abnormality signal is generated if the measured flowrate exceeds the threshold value. This ensures that the temperature of the wafer can be maintained accurately. <IMAGE></p> |
