| 摘要 |
<p>PURPOSE: To obtain electrostatic attraction method and apparatus for supporting a wafer to be processed by plasma in which neutralization of the wafer is detected surely and the wafer is transferred reliably. CONSTITUTION: An aluminum electrode 10 is deposited with an alumina insulation film 11 to constitute an electrostatic attraction electrode 12. Furthermore, a DC power supply 13 for applying negative and positive voltages alternately to the the rear surface of a wafer 1 upon introduction of He gas 19 thereto, and a comparator 22 for comparing a pressure detected through the pressure gauge 20 with a set value 21 are provided. Neutralization of the wafer 1 is ended at a moment in time when the gas pressure on the rear surface of the wafer, detected upon application of a reverse polarity voltage at the time of releasing the wafer 1, is equal to the set value 21, i.e., when the output from the comparator 22 goes 0V.</p> |
