| 摘要 |
<p>PURPOSE: To discharge contaminants from a chamber by intermittently changing or operating a plasma parameter and forming plasma provided with a sheath for suspending particulate contaminants materials from a chuck and moving the particles into the gas discharge flow of the chamber. CONSTITUTION: In the case of executing plasma sheath cleaning of the surface of an electrostatic chuck 78, the plasma parameter normally used in the processing of a workpiece is operated intermittently and changed, and the generation of a plasma 420 of a low density and a plasma sheath 428 is obtained. Then, the particulate contaminants 402 present on the electrostatic chuck 78 are suspended in the plasma sheath 428, entrained in the gas stream 408 and removed by an evacuation processor 26. Also, as the plasma parameters, (1) the flow velocity of plasma generation gas, (2) the size of RF power, (3) a plasma chamber pressure and (4) a magnetic field for achieving a certain plasma density are provided.</p> |
