Kla-tencor Technologies Corporation

Gian Francesco Lorusso

Amir Azordegan

Douglas K Masnaghetti

Luca Grella

Laurence S Hordon

Mark Allen Neil

David Lewis Adler

Alan D Brodie

Gabor D Toth

Srinivas Vedula

Alexander Jozef Gubbens

Hedong Yang

Chris Bevis

Varoujan Chakarian

Waiman Ng

Robert Anthony Watts

Gongyuan Qu

David Goodstein

Srini Vedula

Sander Josef Gubbens

Takuji Tada

Paola De Cecco

Ananthanarayanan Mohan

One embodiment relates to a method of automated microalignment using off-axis beam tilting. Image data is collected from a region of interest on a substrate at multiple beam tilts. Potential edges of a feature to be identified in the region are determined, and computational analysis of edge-related data is performed to positively identify the feature(s). Another embodiment relates to a method of automated detection of undercut on a feature using off-axis beam tilting. For each beam tilt, a determination is made of difference data between the edge measurement of one side and the edge measurement of the other side. An undercut on the feature is detected from the difference data. Other embodiments are also disclosed.

Automated feature analysis with off-axis tilting

One embodiment relates to an electron beam apparatus for automated imaging of a substrate surface. An electron source is configured to emit electrons, and a gun lens is configured to focus the electrons emitted by the electron source so as to form an electron beam. A condenser lens system is configured to receive the electron beam and to reduce its numerical aperture to an ultra-low numerical aperture. An objective lens is configured to focus the ultra-low numerical aperture beam onto the substrate surface. Other embodiments are also disclosed.

Method and apparatus for aberration-insensitive electron beam imaging

The disclosure relates to a method and system of electron beam scanning for measurement, inspection or review. In accordance with one embodiment, the method includes a first scan on a region to collect first image data. The first image data is processed to determine information about a feature in the region. A scanning method is selected for imaging the feature. A second scan using the selected scanning method on the feature is then applied to collect second image data.

Method and system for e-beam scanning

One embodiment disclosed relates to a method for accurate electron beam metrology. A substrate with a target feature is loaded into a scanning electron microscope. An electron beam is scanned over the target feature, and scattered electrons are detected therefrom. A characteristic of the target feature is measured by finding optimal values for parameters of a mathematical model which accounts for substrate charging effects. Principal component analysis may be used to advantageously result in reduced requirements for processing time and/or computational speed.

Method and apparatus for accurate e-beam metrology

One embodiment disclosed relates to a method for automated focusing of an electron image. An EF cut-off voltage is determined. In compensation for a change in the EF cut-off voltage, a focusing condition is adjusted. Adjusting the focusing condition may comprise, for example, adjusting a wafer bias voltage in correspondence to the change in cut-off voltage. Another embodiment disclosed relates to a method for automated focusing of an electron image in a scanning electron imaging apparatus. A focusing condition of a primary electron beam in a first image plane is varied so as to maximize an intensity of a secondary electron beam through an aperture in a second image plane.

Automated focusing of electron image

A method of improving stability for CD-SEM measurements of photoresist, in particular 193 nm photoresist, and of reducing shrinkage of 193 nm photoresist during CD-SEM measurements. The photoresist is exposed to a dose of electrons or other stabilizing beam prior to or during CD measurement. One embodiment of the invention includes multiplexing of the SEM electron beam.

Methods of stabilizing measurement of ArF resist in CD-SEM

A highly accurate technique for inspecting semiconductor devices is described. The technique involves utilizing multiple sets of measurement data obtained by a scanning electron microscope (SEM) to determine the dimensional parameters of a semiconductor device. The SEM collects each set of data from a different angular orientation with respect to the device. The dimensional parameters of the semiconductor device are determined by analyzing the relationship between the SEM inspection angle and the collected data sets. Various configurations of an SEM can be used to implement this invention. For instance an electron beam inspection system of the present invention can have at least two sets of deflectors for guiding the electron beam, a swiveling specimen stage, and/or a set of detectors set about the specimen at different angular orientations.

SEM profile and surface reconstruction using multiple data sets

The present invention pertains to a technique of electron spectroscopic imaging that is easy to perform and cost effective. This technique allows for spatial resolution enhancement of electron beam semiconductor inspection systems (for example a critical dimension scanning electron microscope CD-SEM) as well as to obtain useful physical or chemical information on the investigated specimen. The technique involves a high pass energy filter that is alternately set, or multiplexed, at two energies. For an inspected area on a specimen, the detected intensity level at the higher energy setting is subtracted from the intensity level at the lower energy setting. The obtained differential value corresponds to electrons having energy within the range of the first and second filter settings. This obtained differential value is used to generate an image of the specimen for inspection purposes.

Energy filter multiplexing

The disclosure relates to measuring an undercut of a feature on a specimen using a scanning electron microscope (SEM). In accordance with one embodiment, a method for measuring the undercut includes illuminating the feature with a primary electron beam at an incident angle, changing the incident angle of the primary electron beam over a set of angles, measuring an intensity of scattered electrons from the feature for each incident angle in the set of angles, and determining a discontinuity in the intensities as a function of the incident angle.

Growing community of inventors

Fremont, CA, United States of America

Gian Francesco Lorusso