Patent ID: 6113731
Filing Date: 2000-09-05
Classification: H01J,H01L

Abstract:
A magnetically-enhanced plasma chamber for producing an improved instantaneous spatial uniformity of ion flux from the plasma to a semiconductor workpiece, comprising:a chuck for holding a flat semiconductor workpiece so that the workpiece occupies a workpiece area;a plasma source for producing a plasma in a first region above the workpiece area; anda magnet configured to produce in a planar second region a magnetic field having a non-zero gradient such that, at every point in the second region, the magnetic field at that point has a direction that is approximately the vector cross product of (i) the gradient of the magnitude of the magnetic field at that point, and (ii) a vector extending perpendicularly from the workpiece area toward the plasma;wherein the second region is parallel to and adjacent to the workpiece area and has a surface area substantially greater than half of the workpiece area;wherein, at every instant, the magnetic field has a range of magnitudes in the second region which ranges between a minimum magnitude and a maximum magnitude, wherein the minimum magnitude occurs at only a single point; andwherein, at every instant, the magnetic field has a clockwise curvature relative to said single point when viewed from above the workpiece area.