International Business Machines Corporation

Kla Instruments Corporation

Brian J Grenon

Jacek G Smolinski

Richard Alan Haight

Michael Straight Hibbs

Alfred Wagner

Timothy E Neary

Dennis A Schmidt

Dennis M Hayden

Raymond E Rochefort

J Peter Levin

Zhong-wei Chen

Alan D Brodie

David S O'Grady

Dan Meisburger

Jack Y Jau

Karen Marie Badger

A method of repairing defects on masks includes the step of providing a coating on the mask to prevent damage to clear regions of the mask from laser ablation splatter, laser ablation caused quartz pitting, laser deposition staining, and FIB caused gallium staining. The coating is a metal, a polymer, or a carbon material. The coating is formed on clear regions of the mask as well as either over or under the light absorbing material of the mask. A coating comprising a thin copper layer significantly improves imaging with the ion beam while protecting clear regions of the mask from FIB stain. A coating formed of a photosensitive polymer is used to etch opaque defects. While wanted opaque regions adjacent an opaque defect are also etched in this etch step, these created clear defects are then repaired in a subsequent FIB deposition step while a copper coating protects adjacent clear regions from FIB stain. In another embodiment, opaque defects are repaired with a short pulse duration laser without damage to underlying quartz or adjacent clear regions while avoiding the need for a coating.

Methods for repair of photomasks

Method for repair of photomasks

A method and system for detecting defects in the design of a photolithographic mask or a printed wafer. It derives an adaptive inspection algorithm that allows for a tighter inspection of a mask to a data set which has repeatable differences. The inspection should allow flexibility to remove un-important differences while maintaining a tight inspection capability.

Adaptive inspection method and system

There is disclosed an apparatus to scan an electron beam across an optical phase shift mask and automatically inspect the mask to determine the features of the phase shift mask and classification of defects. An electron beam is directed at the surface of a mask for scanning that mask and detectors are provided to measure the secondary and backscattered charged particles from the surface of the mask. The mask is mounted on an x-y stage to provide it with at least one degree of freedom while the mask is being scanned by the electron beam. By analysis of various waveform features in each of the secondary and backscatter electron waveforms obtained from a phase shift mask, various physical features of the mask can be detected, as well as their size and position determined. The thickness of chromium layers can also be determined. In the inspection configuration, there is also a comparison technique for comparing the pattern on the substrate with a second pattern for error detection.

Inspecting optical masks with electron beam microscopy

Growing community of inventors

Colchester, VT, United States of America

Brian J Grenon