Electron beam system
AssigneeInternational Business Machines Corporation
InventorsJohn L. Mauer, IV, Michel S. Michail, Ollie C. Woodard
Life of this patent
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Abstract
An electron beam method and apparatus, for writing patterns, such as on semiconductor wafers, in which the writing field is divided into a large number of overlapping subfields with a predetermined periodicity. Subfield to subfield moves are made in a stepped sequential scan, such as raster, while patterns, within a subfield, are addressed using vector scan and written using a sequential scan. Significant improvement in throughput results by the use of this electron beam method and apparatus which preferably employs magnetic deflection for the sequential scanning the subfields and electric deflection for vector scanning within the subfield.
Claims16
In an electron beam system adapted for writing patterns within a writing field comprising:
- means for defining an electron beam of predetermined cross section and density;
- means for focusing said beam on a target area within the writing field;
- means for successively directing the beam, while blanked, along a path of a plurality of subfields of the writing field by a first deflection means until it reaches a preselected subfield;
- and
- means for vectoring the beam, while blanked, to a preselected area within said subfield with a second deflection means, whereat the beam is unblanked and a predetermined pattern is written in the preselected area by the beam while the target area is stationary.
A method of writing patterns with an electron beam comprising the steps of:
- defining a predetermined cross section and density of the electron beam;
- focusing the beam on a target area with a writing field;
- successively directing the beam, while blanked, along a path of a plurality of subfields of the writing field until it reaches a preselected subfield;
- and
- vectoring the beam, while blanked, to a preselected area within one of said subfields, whereat the beam is unblanked and a predetermined pattern is written in the preselected area by the beam while the target area is stationary.
Dependencies are inferred from the claim text.