公开(公告)号：SE401883B

公开(公告)日：1978-05-29

申请号：SE7508426

申请日：1975-07-24

Applicant: IBM

Inventor： HALL A ,  PERKINS M H ,  PFEIFFER H C ,  WEBER E V ,  WOODARD O C

IPC: H01J37/305 ,  H01J37/147 ,  H01J37/304 ,  H01L21/027 ,  H01J37/04

Abstract: A beam of charged particles has its alignment and brightness alternately controlled in accordance with the current of the beam. The measurements of the current and any corrections for alignment or brightness are made when the beam is not applied to a target.

公开(公告)号：SE398415B

公开(公告)日：1977-12-19

申请号：SE7507109

申请日：1975-12-27

Applicant: IBM

Inventor： DORAN S K ,  PERKINS M H

IPC: E01C11/26 ,  H01J37/153 ,  H01J37/21 ,  H01J37/244 ,  H01J37/30 ,  H01J37/305 ,  H01L21/027 ,  H05B3/36 ,  H05B3/56

Abstract: A beam of charged particles is deflected in a closed path such as a square, for example, over a cross wire grid at a constant velocity by an X Y deflection system. A small high frequency jitter is added at both axes of deflection to cause oscillation of the beam at 45 DEG to the X and Y axes. From the time that the leading edge of the oscillating beam passes over the wire until the trailing edge of the beam passes over the wire, an envelope of the oscillations produced by the jitter is obtained. A second envelope is obtained when the leading edge of the beam exits from being over the wire until the trailing edge of the beam ceases to be over the wire. Thus, a pair of envelopes is produced as the beam passes over each wire of the grid. The number of pulses exceeding ten per cent of the peak voltage in the eight envelopes produced by the beam completing a cycle in its closed path around the grid are counted and compared with those counted during the previous cycle of the beam moving in its closed path over the grid. As the number of pulses decreases, the quality of the focus of the beam increases so that correction signals are applied to the focus coil in accordance with whether the number of pulses is increasing or decreasing.

公开(公告)号：SE401753B

公开(公告)日：1978-05-22

申请号：SE7506874

申请日：1975-06-16

Applicant: IBM

Inventor： DORAN S K ,  PERKINS M H

IPC: H01J37/147 ,  H01J37/153 ,  H01J37/21 ,  H01L21/027

Abstract: The location of a beam of charged particles within a deflection field is determined by its orthogonal deflection voltages. With the location of the beam in the field, correction currents are supplied to a focus coil and to each of a pair of stigmator coils to correct for change of focal length and astigmatism due to the beam being deflected away from the center of its deflection field.

公开(公告)号：SE7508426L

公开(公告)日：1976-01-27

申请号：SE7508426

申请日：1975-07-24

Applicant: IBM

Inventor： HALL A V ,  PERKINS M H ,  PFEIFFER H C ,  WEBER E V ,  WOODARD O C

IPC: H01J37/305 ,  H01J37/147 ,  H01J37/304 ,  H01L21/027 ,  H01J37/04

Abstract: A beam of charged particles has its alignment and brightness alternately controlled in accordance with the current of the beam. The measurements of the current and any corrections for alignment or brightness are made when the beam is not applied to a target.

公开(公告)号：SE7507109L

公开(公告)日：1975-12-29

申请号：SE7507109

申请日：1975-12-27

Applicant: IBM

Inventor： DORAN S K ,  PERKINS M H

IPC: E01C11/26 ,  H01J37/153 ,  H01J37/21 ,  H01J37/244 ,  H01J37/30 ,  H01J37/305 ,  H01L21/027 ,  H05B3/36 ,  H05B3/56 ,  H01J37/04

Abstract: A beam of charged particles is deflected in a closed path such as a square, for example, over a cross wire grid at a constant velocity by an X Y deflection system. A small high frequency jitter is added at both axes of deflection to cause oscillation of the beam at 45 DEG to the X and Y axes. From the time that the leading edge of the oscillating beam passes over the wire until the trailing edge of the beam passes over the wire, an envelope of the oscillations produced by the jitter is obtained. A second envelope is obtained when the leading edge of the beam exits from being over the wire until the trailing edge of the beam ceases to be over the wire. Thus, a pair of envelopes is produced as the beam passes over each wire of the grid. The number of pulses exceeding ten per cent of the peak voltage in the eight envelopes produced by the beam completing a cycle in its closed path around the grid are counted and compared with those counted during the previous cycle of the beam moving in its closed path over the grid. As the number of pulses decreases, the quality of the focus of the beam increases so that correction signals are applied to the focus coil in accordance with whether the number of pulses is increasing or decreasing.

公开(公告)号：SE7506874L

公开(公告)日：1975-12-27

申请号：SE7506874

申请日：1975-06-16

Applicant: IBM

Inventor： DORAN S K ,  PERKINS M H

IPC: H01J37/147 ,  H01J37/153 ,  H01J37/21 ,  H01L21/027 ,  H01J37/04

Abstract: The location of a beam of charged particles within a deflection field is determined by its orthogonal deflection voltages. With the location of the beam in the field, correction currents are supplied to a focus coil and to each of a pair of stigmator coils to correct for change of focal length and astigmatism due to the beam being deflected away from the center of its deflection field.