Title:
AUTOMATIC REGULATION OF BEAM-SCAN OFFSET SYSTEM IN ION-IMPLANTATION EQUIPMENT
Document Type and Number:
Japanese Patent JPS5951525
Kind Code:
A
Abstract:
PURPOSE:To make automatic regulation of beam-scan offset possibe by a method wherein a delayed beam current value is integrated according to the beam scanning direction and the DC offset of a scanning source is regulated according to the integrated value. CONSTITUTION:An ion beam 1 is injected to a target 2 and a target current I is induced. The current I is converted to a voltage signal by a I/V converter 3 and delayed by a signal delaying circuit 4 and introduced to integrating circuits 7, 8 while being given intermittent on-offs by analogue switches 5, 6. The analogue switches 5, 6 are controlled by control signals and the signal for one switch has the reverse phase against that for another. The output of the integrating circuit 7 and that of the circuit 8 are identical when the center of the scanning of the scanning ion beam coincides the center of the target. A difference of output is obtained by a reduction circuit 12 from the output voltage of the integrating circuit 7, 8 and this difference becomes an error signal. This error signal regulates offset automatically by controlling DC bias voltage.
Inventors:
TSUNENARI YOSHITSUGU
Application Number:
JP16186782A
Publication Date:
March 26, 1984
Filing Date:
September 17, 1982
Export Citation:
Assignee:
NIPPON ELECTRIC CO
International Classes:
H01J37/317; H01L21/265; (IPC1-7): H01J37/00
Attorney, Agent or Firm:
Uchihara Shin