Patent ID: 8319197

Claim:
A frequency adjusting apparatus comprising: a conveying unit configured to convey, in one direction, a wafer on which a plurality of elements are closely arranged; an ion gun for etching, the ion gun being configured to irradiate the wafer with an ion beam while the wafer is being conveyed; a pattern mask having a plurality of mask holes allowing only target areas of the wafer to be exposed, the pattern mask being disposed upstream of the wafer in a direction in which the ion beam travels; and a plurality of shutters each being configured to adjust an irradiation time during which a target area is irradiated with the ion beam, and thereby adjust a frequency in the target area, wherein each of the plurality of mask holes in the pattern mask corresponds to one area of the wafer; the plurality of mask holes being alternately displaced in a wafer conveying direction in which the wafer is conveyed, and arranged in a plurality of columns perpendicular to the wafer conveying direction; the shutters being arranged to correspond to the respective plurality of mask holes to individually open and close the corresponding plurality of mask holes; and frequency adjustment, for areas in one column perpendicular to the wafer conveying direction, being performed in multiple steps.