BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and features of the present invention will become apparent from the following description of exemplary embodiments given in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic cross sectional view of a semiconductor wafer to which an etching method of the present invention is applied;
FIG. 2 sets forth a schematic cross sectional view of a semiconductor wafer processed by the etching method of the present invention;
FIG. 3 is a schematic cross sectional view of a semiconductor wafer processed by a conventional etching method;
FIG. 4 offers a cross sectional view of a parallel plate type plasma etching apparatus suitable for performing the etching method of the present invention;
FIG. 5 depicts a schematic horizontal cross sectional view of multipole ring magnets disposed around a chamber of the etching apparatus of FIG. 4; and
FIGS. 6A to 6C provide diagrams which demonstrate rotational motions of the segment magnets of FIG. 4 and their resulting variations in a magnetic field.