Electron beam aligner

Abstract

Abstract PURPOSE:To reduce the generation of an eddy current and to suppress a convergence-disturbing action on an electron beam by a method wherein a bore made in the lower-part pole piece facing an object such as a semiconductor wafer or the like to be irradiated with the electron beam is formed so as to correspond to a scanning space of the electron beam. CONSTITUTION:This aligner is constituted by including a magnetic objective having a lower-part pole piece 31b which is installed so as to be opposite to an object; a bore 33b is opened in the lower-part pole piece 31b so as to correspond to a prescribed scanning space of an electron beam to be scanned in a direction perpendicular to a main shift direction of the object. This bore lets the electron beam pass through this bore; most of a magnetic flux of the magnetic objective is arrested in a part other than the bore 33b in the lower-part pole piece 31b and is prohibited from being leaked to a stage 11. Accordingly, it is possible to avoid that an eddy current is generated inside the stage by a leakage flux; a good convergence of the electron beam can be maintained. Thereby, since the convergence of the electron beam is enhanced, it is possible to prevent an unnecessary magnetic flux from being leaked from the magnetic objective to a direction of the stage.

Inventors

• 👤 Hiroshi Yasuda
• 👤 洋 安田
• 👤 Masahiko Suzuki
• 👤 正彦 鈴木

Bibliographic Details