International Business Machines Corporation

Denise M Puisto

Harold G Linde

John George Hartley

Charles Arthur Whiting

Gregory J Dick

Abigail S Ganong

John W Pavick

Douglas Earl Benoit

An e-beam system for making masks corrects the beam for pattern-dependent errors by executing the bulk of the post-processing program only once, with two sets of output data being generated by the encode routine. A first output file of the encode routine generates the beam control data without pattern-dependent corrections. A second output file merges the beam control data with the data for metrology marks. A test wafer is patterned using the second output file and measured to generate a set of pattern correction data. Production wafers are written using the beam control data corrected on the fly by the pattern correction data.

Correction of pattern-dependent errors in a particle beam lithography system

A temperature-sensitive film such as a resist is baked onto a semiconductor substrate such as a mask blank by immersion in a heated liquid. A barrier coating may optionally be applied to the substrate prior to immersion and later removed. The substrate is subsequently cooled by immersing the substrate in a cooling liquid or dissolving the heated liquid from the substrate with a rinsing liquid at a temperature sufficiently lower than that of the heated liquid. Temperature uniformity within .+-.0.2.degree. C. is thereby achieved across the regions of varying thickness in the silicon wafer and membrane. Where a resist has been deposited on the mask blank substrate, heating and cooling by immersion results in improved line size control after exposure and development down to 0.25 .mu.m.

Liquid immersion heating process for substrate temperature uniformity

A technique for creating an improved mask used in the semiconductor industry for replicating desired images in semiconductor bodies. The invention has application in both direct writing and blind writing processes and employs the steps of writing, in a sacrificial photoresist, a selected pattern of marks with an E-beam lithography system, measuring the actual pattern created and modifying the magnetic and electrostatic force used to control the beam to correct for stage translational errors, magnification, drift, mirror distortion, and column charging, caused by either mechanical aspects or by electrical problems in the system. A prototype mask is then created containing the actual image to be replicated, the image being provided with a plurality of alignment marks, and the actual positions of the marks in the prototype mask are measured. The magnetic and electrostatic forces used to create the prototype mask are modified to correct for process stress induced errors, localized heating and charging distortions, and effects due to the shape and layout of the pattern being created. As the last step, a final mask, suitable for use on the production line, is produced with the modified information.

Pattern specific calibration for E-beam lithography

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Milton, VT, United States of America

Denise M Puisto