The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 17, 1998
Filed:
Apr. 04, 1996
Takamasa Satoh, Kawasaki, JP;
Hiroshi Yasuda, Kawasaki, JP;
Junichi Kai, Kawasaki, JP;
Yoshihisa Oae, Kawasaki, JP;
Hisayasu Nishino, Kawasaki, JP;
Kiichi Sakamoto, Kawasaki, JP;
Hidefumi Yabara, Kawasaki, JP;
Isamu Seto, Kawasaki, JP;
Masami Takigawa, Kawasaki, JP;
Akio Yamada, Kawasaki, JP;
Soichiro Arai, Kawasaki, JP;
Tomohiko Abe, Kawasaki, JP;
Takashi Kiuchi, Kawasaki, JP;
Kenichi Miyazawa, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
To improve the throughput of an exposure system, the setting time during a step change in the output of an amplifier is reduced by switching resistance between the amplifier and a deflector. A glitch waveform generated during a step change in the output of a D/A converter at the preceding stage of the amplifier is anticipated and is cancelled out with a correction waveform. After the output of the D/A converter has settled, this output is sample-held and the step change is interpolated with a smoothing circuit. The deflection area is increased by positioning an electrostatic deflector offset around the optical axis relative to another electrostatic deflector, and the response speed of the main deflection is improved by adding auxiliary deflection coils of one or two turns. The alignment time is reduced by combining the coordinate conversion in the wafer area and in the chip area. In order to correct the astigmatism of the electromagnetic lens, two stages of coils are provided and an electric current corresponding to the quantity of deflection is supplied to the coils.