A shielding device for shielding an edge of a semiconductor substrate can include a multisided frame defining a perimeter of an enclosed area, and a shield coupled to the frame. The shield may be configured to move between a first position where the shield is retracted to the perimeter and a second position where shield advanced into the enclosed area. A method for processing a semiconductor substrate includes placing a semiconductor substrate in position in an implantation chamber, covering edges of the semiconductor substrate by pushing shields into engagement with the edges, performing an ion implantation procedure, and retracting the shields from the edges.