Kla-tencor Technologies Corporation

Other

Kla Tencor Corporation

Patrick M Maxton

Gary Janik

Mehrdad Nikoonahad

Kenneth C Johnson

Haiming Wang

Hidong Kwak

Liang-Guo Wang

James McWhirter

Haixing Zou

Dan G Georgesco

Bernard Lautee

Jennming James Chen

A system for analyzing a thin film uses an energy beam, such as a laser beam, to remove a portion of a contaminant layer formed on the thin film surface. This cleaning operation removes only enough of the contaminant layer to allow analysis of the underlying thin film, thereby enhancing analysis throughput while minimizing the chances of recontamination and/or damage to the thin film. An energy beam source can be readily incorporated into a conventional thin film analysis tool, thereby minimizing total analysis system footprint. Throughput can be maximized by focusing the probe beam (or probe structure) for the analysis operation at the same location as the energy beam so that repositioning is not required after the cleaning operation. Alternatively, the probe beam (structure) and the energy beam can be directed at different locations to reduce the chances of contamination of the analysis optics.

Laser-based cleaning device for film analysis tool

Methods and systems for preparing a sample for thin film analysis are provided. One system includes an energy beam source configured to generate an energy beam. The system also includes an energy beam delivery subsystem configured to direct the energy beam to a sample and to modify the energy beam such that the energy beam has a substantially flat-top profile on the sample. The energy beam removes a portion of a contaminant layer on the sample to expose an analysis area of a thin film on the sample. One method includes generating an energy beam and modifying the energy beam such that the energy beam has a substantially flat-top profile. The method also includes directing the energy beam to a sample. The energy beam removes a portion of a contaminant layer on the sample to expose an analysis area of a thin film on the sample.

Methods and systems for preparing a sample for thin film analysis

Two phase modulators or polarizing elements are employed to modulate the polarization of an interrogating radiation beam before and after the beam has been modified by a sample to be measured. Radiation so modulated and modified by the sample is detected and up to 25 harmonics may be derived from the detected signal. The up to 25 harmonics may be used to derive ellipsometric and system parameters, such as parameters related to the angles of fixed polarizing elements, circular deattenuation, depolarization of the polarizing elements and retardances of phase modulators. A portion of the radiation may be diverted for detecting sample tilt or a change in sample height. A cylindrical objective may be used for focusing the beam onto the sample to illuminate a circular spot on the sample. The above-described self-calibrating ellipsometer may be combined with another optical measurement instrument such as a polarimeter, a spectroreflectometer or another ellipsometer to improve the accuracy of measurement and/or to provide calibration standards for the optical measurement instrument. The self-calibrating ellipsometer as well as the combined system may be used for measuring sample characteristics such as film thickness and depolarization of radiation caused by the sample.

System for analyzing surface characteristics with self-calibrating capability

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San Jose, CA, United States of America

Patrick M Maxton