Kla Instruments Corporation

Jack Y Jau

Alan D Brodie

Dan Meisburger

Zhong-wei Chen

David J Clark

Lee H Veneklasen

Chung-Shih Pan

Curt H Chadwick

John S Taylor

John D Greene

Richard R Simmons

Ralph T Johnson

Eric Munro

Brian J Grenon

Chetana Bhaskar

Anil A Desai

Timothy L Hutcheson

Barry Becker

John McMurtry

April Dutta

Dennis G Emge

Paul Wieczorek

Henry Pearce-Percy

Kirkwood Rough

Hoi T Nguyen

Yen-Jen Oyang

Chris Kirk

Ming-Yie Ling

Hans Dohse

Ray Paul

Mike Robinson

David E Smith

Dean Walters

Sam Wong

Surendra Lele

Chun C Lin

An apparatus scans an electron beam across an optical phase shift mask and automatically inspects 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

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.

There is disclosed numerous embodiments of a method and apparatus for a particle scanning system and an automatic inspection system. In each of these a particle beam is directed at the surface of a substrate for scanning that substrate. Also included are a selection of detectors to detect at least one of the secondary particles, back-scattered particles and transmitted particles from the substrate. The substrate is mounted on an x-y stage to provide it with at least one degree of freedom while the substrate is being scanned by the/particle beam. The substrate is also subjected to an electric field on it's surface to accelerate the secondary particles. The system also has the capability to accurately measure the position of the substrate with respect to the charged particle beam. Additionally, there is an optical alignment means for initially aligning the substrate beneath the,particle beam means. To function most efficiently there is also a vacuum means for evacuating and repressurizing a chamber containing the substrate. The vacuum means can be used to hold one substrate at vacuum while a second one is being loaded/unloaded, evacuated or repressurized. Alternately, the vacuum means can simultaneously evacuate a plurality of substrates prior to inspection and repressurize of the same plurality of substrates following inspection. In the inspection configuration, there is also a comparison means for comparing the pattern on the substrate with a second pattern.

Electron beam inspection system and method

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Fremont, CA, United States of America

Jack Y Jau