Kla Tencor Corporation

Kla-tencor Technologies Corporation

Other

Kla Instruments Corporation

John D Greene

Curt H Chadwick

Michael E Fein

William T Bell

Xinrong Jiang

Liqun Han

Robert R Sholes

P C Jann

Francis D Tucker, Iii

Jamie Michael Sullivan

Ralph C Wolf

Eric Vella

David J Harvey

Eva L Benitez

Khiem D Vo

David J Clark

Marian Mankos

Lee H Veneklasen

Alan D Brodie

Kirk Joseph Bertsche

Chung-Shih Pan

Mark Joseph Wihl

John S Taylor

Salam Harb

Mohammed Tahmassebpur

Ralph T Johnson

Richard R Simmons

Eric Munro

Rex Runyon

Chetana Bhaskar

Anil A Desai

Dan Meisburger

Timothy L Hutcheson

Barry Becker

John McMurtry

Jack Y Jau

April Dutta

Paul Wieczorek

Dennis G Emge

Henry Pearce-Percy

Kirkwood Rough

Bin-Ming B Isai

David J Harney

Walter I Novak

Ming-Yie Ling

Hans Dohse

Ray Paul

Mike Robinson

Dongsheng (Don) Chen

David E Smith

Dean Walters

Sam Wong

Surendra Lele

Dongsheng Don Chen

Chun C Lin

Hoi T Nguyen

Yen-Jen Oyang

Chris Kirk

Disclosed are apparatus and methods for the generation of a stage speed profile and/or the selection of care areas for automated wafer inspection. The stage speed profile generated corresponds to a fastest speed the inspection machine is able to inspect provided a set of care areas. The set of care areas selected correspond to specific regions on the wafer which are to be imaged in detail by the inspection machine. The apparatus and methods herein may also calculate speed of inspection and coverage (and possibly other characteristics of the inspection) for a quantity of cases, and select the best trade-off of coverage versus inspection time using a cost function. Other aspects, features, and embodiments of the invention are also disclosed.

Methods and apparatus for optimization of inspection speed by generation of stage speed profile and selection of care areas for automated wafer inspection

The present disclosure provides an electron beam column with substantially improved resolution and/or throughput for inspecting manufactured substrates. The electron beam column comprises an electron gun, a scanner, an objective lens, and a detector. In accordance with one embodiment, the electron gun includes a gun lens having a flip-up pole piece configuration. In accordance with another embodiment, the scanner comprises a dual scanner having a pre-scanner and a main scanner, and the detector may be configured between the electron gun and the pre-scanner. In accordance with another embodiment, the electron beam column includes a continuously-variable aperture configured to select a beam current. Other embodiments relate to methods of using an electron beam column for automated inspection of manufactured substrates. In one embodiment, for example, an aperture size is adjusted to achieve a minimum spot size given a selected beam current and a column-condition domain being used.

Electron-optical system for high-speed and high-sensitivity inspections

One embodiment disclosed relates to a multiple-beamlet electron beam imaging apparatus for imaging a surface of a target substrate. A beam splitter lens array is configured to split the illumination beam to form a primary beamlet array, and a scanning system is configured to scan the primary beamlet array over an area of the surface of the target substrate. In addition, a detection system configured to detect individual secondary electron beamlets. Another embodiment disclosed relates to a method of imaging a surface of a target substrate using a multiple-beamlet electron beam column. Other features and embodiments are also disclosed.

Multiple-beam system for high-speed electron-beam inspection

One embodiment relates to an electron-beam apparatus for defect inspection and/or review of substrates or for measuring critical dimensions of features on substrates. The apparatus includes an electron gun and an electron column. The electron gun includes an electron source configured to generate electrons for an electron beam and an adjustable beam-limiting aperture which is configured to select and use one aperture size from a range of aperture sizes. Another embodiment relates to providing an electron beam in an apparatus. Advantageously, the disclosed apparatus and methods reduce spot blur while maintaining a high beam current so as to obtain both high sensitivity and high throughput.

High-sensitivity and high-throughput electron beam inspection column enabled by adjustable beam-limiting aperture

One embodiment described relates to a method of electron beam imaging of a target area of a substrate. An electron beam column is configured for charge-control pre-scanning using a primary electron beam. A pre-scan is performed over the target area. The electron beam column is re-configured for imaging using the primary electron beam. An imaging scan is then performed over the target area. Other embodiments are also described.

Charge-control pre-scanning for e-beam imaging

Disclosed are methods and apparatus for detecting a relatively wide dynamic range of intensity values from a beam (e.g., scattered light, reflected light, or secondary electrons) originating from a sample, such as a semiconductor wafer. In other words, the inspection system provides detected output signals having wide dynamic ranges. The detected output signals may then be analyzed to determine whether defects are present on the sample. For example, the intensity values from a target die are compared to the intensity values from a corresponding portion of a reference die, where a significant intensity difference may be defined as a defect. In a specific embodiment, an inspection system for detecting defects on a sample is disclosed. The system includes a beam generator for directing an incident beam towards a sample surface and a detector positioned to detect a detected beam originating from the sample surface in response to the incident beam. The detector has a sensor for detecting the detected beam and generating a detected signal based on the detected beam and a non-linear component coupled to the sensor. The non-linear component is arranged to generate a non-linear detected signal based on the detected signal. The detector further includes a first analog-to-digital converter (ADC) coupled to the non-linear component. The first ADC is arranged to digitize the non-linear detected signal into a digitized detected signal.

Apparatus and methods for optically inspecting a sample for anomalies

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

In each configuration, at least one TDI sensor is used to image substrate portions of interest, with those portions illuminated with substantially uniform illumination. In one configuration, a substrate is compared to prestored expected characteristic features. In a second configuration, first and second patterns in a region of the surface of at least one substrate are inspected by comparing one pattern against the other and noting whether they agree with each other. This is accomplished by illuminating the two patterns, imaging the first pattern and storing its characteristics in a temporary memory, then imaging the second pattern and comparing it to the stored characteristics from the temporary memory. Then the comparisons continue sequentially with the second pattern becoming the first pattern in the next imaging/comparison sequence against a new second pattern. Each time the comparison is performed, it is noted whether or not there has been agreement between the two patterns and which two patterns where compared. This inspection technique is useful for doing die-to-die inspections. A variation of the second configuration uses two TDI sensors to simultaneously image the first and second patterns, thus eliminating the need for temporary memory. In this configuration, the two patterns are simultaneously imaged and compared, then additional patterns are compared sequentially, in the same manner with the results of the comparisons and the pattern locations stored to determine which patterns are bad when the inspection of all patterns is completed.

Automatic high speed optical inspection system

In each configuration, at least one TDI sensor is used to image the portions of interest of the substrate that are substantially uniformly or critically illuminated. In one configuration, the substrate is compared to the expected characteristic features prestored in memory. In a second configuration, a first and second pattern in a region of at least one substrate are inspected by comparing one pattern against the other and noting whether they agree with each other. This is accomplished by illuminating the two patterns, imaging the first pattern and storing its characteristics in a temporary memory, then imaging the second pattern and comparing it to the stored characteristics from the temporary memory. Then the comparisons continue sequentially with the second pattern becoming the first pattern in the next imaging/comparison sequence against a new second pattern. With each comparison whether there has been agreement between the two patterns is noted. After all of the patterns are sequentially compared, the bad ones are identified by identifying those that did not compare with other patterns in the test process. This inspection technique is useful for doing die-to-die inspections, as well as repeating patern inspections within the same die. A variation of the second configuration uses two TDI sensors to simultaneously image the first and second patterns eliminating the need for the temporary memory.

Substrate inspection apparatus and methods, and illumination apparatus. The inspection apparatus and method includes memory for storing the desired features of the surface of the substrate, focussed illuminator for substantially uniformly illuminating a region of the surface of the substrate to be inspected. Additionally there is a sensor for imaging the region of the substrate illuminated by the illuminator, and a comparator responsive to the memory and sensor for comparing the imaged region of the substrate with the stored desired features of the substrate. The illumination apparatus is designed to provide substantially uniform focussed illumination along a narrow linear region. This apparatus includes first, second and third reflectors elliptically cylindrical in shape, each with its long axis substantially parallel to the long axes of each of the others. Fourth and fifth reflectors are also included with each being flat and mounted parallel to each other and at opposite ends of each of said first, second and third reflectors, and first, second and third linear light sources each mounted parallel to a corresponding one of said first, second and third reflectors with each of the light sources mounted so that it is at the first focus of the corresponding reflector and the illuminated linear region is at the second focus of each of the first, second and third reflectors.

Method and apparatus for optical inspection of substrates

Growing community of inventors

Santa Cruz, CA, United States of America

John D Greene