| 摘要 |
<p>PURPOSE:To surely perform release of a wafer by providing a driving mean for electrically insulating a piezoelectric element from electrodes for generating electrostatic force on a dielectric and wafer. CONSTITUTION:As a wafer 3 is brought in contact with the dielectric 2 of an electrostatic chuck and voltage is applied between electrodes 1a, 1b by a power supply 6, the wafer 3 is attracted with the electrostatic force. Thus, after the desired processing is applied, the applied voltage is released by the power supply 6. In this state, the wafer is kept to be attracted under polarization generated on the dielectric 2. Next, as voltage is applied on the piezoelectric element 4a by a power supply 7, it is extended so as to receive the release force exceeding the attractive force due to the polarization generated on the dielectric 2, thus surely releasing the wafer from the dielectric 2. As the voltage applied on the piezoelectric element 4a is released, the piezoelectric element 4a is returned in the original length. In this case, the piezoelectric element 4a is electrically insulated from the wafer 3 and electrodes 1a, 2b so that there occurs no trouble even if the voltage is applied on the piezoelectric element 4.</p> |
