US 7,253,901 B2 · Laser-based cleaning device for film analysis tool

Abstract

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.

Claims28

Dependent claims

A thin film analysis system for analyzing a test sample, the test sample comprising a thin film formed on a substrate and a contaminant layer formed on the thin film, the thin film analysis system comprising:

an energy beam source for directing an energy beam at the contaminant layer during a localized cleaning operation, the energy beam being configured to heat only a small area of the contaminant layer until the small area is vaporized, thereby creating an opening in the contaminant layer;
and
a thin film analysis module for performing at least one of single wavelength ellipsometry (SWE), spectroscopic ellipsometry (SE), reflectometry, grazing incidence x-ray reflectometry (GXR), x-ray fluorescence (XRF), electron microprobe analysis (EMP), non-contact-based electrical analysis, and contact-based electrical analysis on the thin film through the opening in the contaminant layer.

A method for analyzing a test sample, wherein a contaminant layer covers a thin film of the test sample, the method comprising:

placing the test sample on a stage;
during a localized cleaning operation, directing an energy beam at a first location on the contaminant layer while the test sample is on the stage, the energy beam heating only a small area of the contaminant layer until the small area is vaporized, thereby removing a first portion of the contaminant layer to create an opening in the contaminant layer to expose a first analysis area of the thin film;
performing at least one of single wavelength ellipsometry (SWE), spectroscopic ellipsometry (SE), reflectometry, grazing incidence x-ray reflectometry (GXR), x-ray fluorescence (XRF) electron microprobe analysis (EMP), non-contact-based electrical analysis, and contact-based electrical analysis on the thin film at the first analysis area through the opening in the contaminant layer while the test sample is on the stage;
and
generating an analysis output regarding the thin film.

2 more elements

Dependencies are inferred from the claim text.

Laser-based cleaning device for film analysis tool

Life of this patent

Laser-based cleaning device for film analysis tool

Life of this patent

Abstract

Claims28