International Business Machines Corporation

Gary J Johnson

David J Pinckney

Rodney A Kendall

A carrier for the masks used in Electron Projection Lithography, or other workpieces used in nanotechnology fields, comprises a rectangular frame having a set of four electrostatic chucks in the top surface for holding the mask above a central aperture that has an electron absorber on the bottom for suppressing backscattering; the frame being supported by a bottom carrier that grips the frame with a set of flexures flexible in the z-direction, stiff in an azimuthal direction and flexible in a radial direction.

Mask carrier

In a particle beam lithography system, focus adjustment is controlled by a measurement of the gap between the workpiece being processed and a reference surface, such as the bottom surface of the focus lens, using a pair of capacitive sensors mounted on an arm that rotates to place one sensor on the beam axis to measure the workpiece height and the other displaced from the beam aperture to measure the height of the reference surface. The sum of the two readings is constant (for a given gap dimension), so that the accuracy of the measurement is not affected by the position of the arm within the gap.

Growing community of inventors

Wappingers Falls, NY, United States of America

Gary J Johnson