MATERIAL DEPOSITION PREVENTION ON A WORKPIECE IN A PROCESS CHAMBER

Focus ring assemblies for plasma processing apparatus are provided. In one example implementation, an apparatus includes a plasma source configured to generate a plasma. The apparatus includes a chamber configured to receive a workpiece. The apparatus includes a workpiece support contained in the chamber and configured to support the workpiece. The apparatus includes a focus ring assembly. The focus ring assembly includes a focus ring having an upper tier and a lower tier. An inner edge of the upper tier can be separated a lateral distance of at least about 3 mm from an outer edge of the workpiece located on the workpiece support. 本公开提供了一种用于等离子体处理设备的聚焦环组件。在一个示例性实施方式中，设备包括配置成生成等离子体的等离子体源。该设备包括配置成接收工件的腔室。该设备包括容纳在腔室中并且配置成支撑工件的工件支撑件。该设备包括聚焦环组件。聚焦环组件包括具有上层和下层的聚焦环。上层的内边缘可以从位于工件支撑件上的工件的外边缘分开至少约3mm的侧向距离。