Kla Tencor Corporation

Kla Corporation

Chunhai Wang

Shouhong Tang

Chunsheng J Huang

Yi Zhang

Anatoly Romanovsky

Bret Whiteside

Andrew An Zeng

Frederick Arnold Goodman

Christian Wolters

Daniel Ivanov Kavaldjiev

Zhiwei Xu

Donald Pettibone

Andrew Zeng

Jenn-Kuen Leong

Chuanyong Huang

Steve (Yifeng) Cui

A dark-field optical system may include a rotational objective lens assembly with a dark-field objective lens to collect light from a sample within a collection numerical aperture, where the dark-field objective lens includes an entrance aperture and an exit aperture at symmetrically-opposed azimuth angles with respect to an optical axis, a rotational bearing to allow rotation of at least a part of the dark-field objective lens including the entrance aperture and the exit aperture around the optical axis, and a rotational driver to control a rotational angle of the entrance aperture. The system may also include a multi-angle illumination sub-system to illuminate the sample with an illumination beam through the entrance aperture at two or more illumination azimuth angles, where an azimuth angle of the illumination beam on the sample is selectable by rotating the objective lens to any of the two or more illumination azimuth angles.

Apparatus and method for rotating an optical objective

Methods and systems for reducing illumination intensity while scanning over large particles are presented herein. A surface inspection system determines the presence of a large particle in the inspection path of a primary measurement spot using a separate leading measurement spot. The inspection system reduces the incident illumination power while the large particle is within the primary measurement spot. The primary measurement spot and the leading measurement spot are separately imaged by a common imaging collection objective onto one or more detectors. The imaging based collection design spatially separates the image of the leading measurement spot from the image of the primary measurement spot at one or more wafer image planes. Light detected from the leading measurement spot is analyzed to determine a reduced power time interval when the optical power of the primary illumination beam and the leading illumination beam are reduced.

Surface defect inspection with large particle monitoring and laser power control

A semiconductor measuring tool has a folding mirror configuration that directs a light beam to pass the same space multiple times to reduce the size and footprint. Furthermore, the folding mirrors may reflect the light beam at less than forty-five degrees; thereby allowing for smaller folding mirrors as compared to the prior art.

Method and apparatus to fold optics in tools for measuring shape and/or thickness of a large and thin substrate

A calibration wafer and a method for calibrating an interferometer system are disclosed. The calibration method includes: determining locations of the holes defined in the calibration wafer based on two opposite intensity frame; comparing the locations of the holes against the locations measured utilizing an external measurement device; adjusting a first optical magnification or a second optical magnification at least partially based on the comparison result; defining a distortion map for each of the first and second intensity frames based on the comparison of the locations of the holes; generating an extended distortion map for each of the first and second intensity frames by map fitting the distortion map; and utilizing the extended distortion map for each of the first and second intensity frames to reduce at least one of: a registration error or an optical distortion in a subsequent measurement process.

Reducing registration error of front and back wafer surfaces utilizing a see-through calibration wafer

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Pleasanton, CA, United States of America

Chunhai Wang