Patent ID: 6444991
Filing Date: 2002-09-03
Classification: H01J

Abstract:
A scanning charged-particle beam instrument comprising:a specimen stage assembly including a combination of an X-Y stage for translation along X and Y axes and a rotating stage secured to said X-Y stage, said rotating stage having a center of rotation and a rotation axis normal to the X and Y axes; means for directing a charged-particle beam to a specimen placed on said specimen stage assembly; means for scanning said charged-particle beam in two dimensions across said specimen; a detector for detecting signals arising from said specimen; means for displaying a scanned image of said specimen on a viewing screen in response to an output signal from said detector, said scanned image having a selected position that is at a distance of L from the center of rotation of said rotating stage; and a control means for repositioning said X-Y stage according to the angular rotation of said rotating stage and the said distance L such that the scanned image rotates about the selected position on the viewing screen and such that said control means controls the moving speed of said X-Y stage according to said distance L.