Patent ID: 7772576

Claim:
A shielding assembly for a semiconductor device, comprising: a first shielding member disposed at an inner bottom surface of a chamber through which a high-energy ion beam passes, the bottom surface having a bottom magnetic area; a second shielding member disposed at a top surface of the chamber, the top surface having a top magnetic area, the second shielding member covering a portion of the top surface of the chamber, including the top magnetic area; a third shielding member disposed at a side surface in the chamber extending between the top and bottom surfaces of the chamber, wherein the first, second and third shielding members are jointed with one another in such a manner that an edge portion of the first shielding member contacts a bottom edge portion of the third shielding member and an edge portion of the second shielding member contacts a top edge portion of the third shielding member; a fourth shielding member for at least partially covering another portion of the top surface of the chamber in a side-by-side relationship with the second shielding member, wherein the second and fourth shielding members are jointed with one another in such a manner that an edge portion of the fourth shielding member contacts an adjacent edge portion of the second shielding member; and a support mechanism adapted for mounting in the chamber in a position such that the support mechanism supports the fourth shielding member in opposing relationship to the top surface of the chamber; wherein the support mechanism is configured to vary the tilt of the fourth shielding member relative to the top surface.