METHODS OF AND APPARATUS FOR PROTECTING A REGION OF PROCESS EXCLUSION ADJACENT TO A REGION OF PROCESS PERFORMANCE IN A PROCESS CHAMBER

摘要

Apparatus and methods protect a central process exclusion region of a substrate during processing of an edge environ region of process performance. Removal of undesired materials is only from the edge environ region while the central device region is protected from damage. Field strengths are configured to protect the central region from charged particles from plasma in a process chamber and to foster removal of the undesired materials from only the edge environ region. A magnetic field is configured with a peak value adjacent to a border between the central and edge environ regions. A strong field gradient extends from the peak radially away from the border and away from the central region to repel the charged particles from the central region. The strength and location of the field are adjustable by axial relative movement of magnet sections, and flux plates are configured to redirect the field for desired protection.