Kla Tencor Corporation

Kla-tencor Technologies Corporation

Kla Instruments Corporation

Tao-Yi Fu

Christopher R Fairley

Bin-Ming Benjamin Tsai

Damon Floyd Kvamme

Shiow-Hwei Hwang

Michael E Fein

Gershon Perelman

Mark Joseph Wihl

Marek Zywno

Scott Allen Young

Steve R Lange

Grace Hsiu-Ling Chen

Daimian Wang

Paul Frank Marella

Nat Ceglio

Xiumei Liu

Zain Kahuna Saidin

David Garth Emery

Lisheng Gao

Shing Lee

Daniel C Wack

Jamie Michael Sullivan

Xuguang Jiang

Grace Jing Chen

Sylvain Muckenhirn

Evan R Mapoles

Greg Kirk

Ping Gu

Dragos Maciuca

Bin-Ming Benjanim Tsai

Methods and systems for monitoring a non-defect related characteristic of a patterned wafer are provided. One computer-implemented method includes generating output responsive to light from a patterned wafer using an inspection system. The method also includes determining differences between a value of a non-defect related characteristic of the patterned wafer and a known value of the non-defect related characteristic based on differences between one or more attributes of the output and one or more attributes of other output of the inspection system for a different patterned wafer having the known value of the non-defect related characteristic.

Methods and systems for monitoring a non-defect related characteristic of a patterned wafer

Methods and systems for source multiplexing illumination for mask inspection are disclosed. Such illumination systems enable EUV sources of small brightness to be used for EUV mask defect inspection at nodes below the 22 nm. Utilizing the multiple plane or conic mirrors that are either attached to a continuously rotating base with different angles or individually rotating to position for each pulse, the reflected beams may be directed through a common optical path. The light may then be focused by a condenser to an EUV mask. The reflected and scattered light from the mask may then be imaged by some imaging optics onto some sensors. The mask image may be subsequently processed for defect information.

Source multiplexing illumination for mask inspection

The disclosure is directed to a system and method of providing illumination for reticle inspection. According to various embodiments of the disclosure, a multiplexing mirror system receives pulses of illumination from a plurality of illumination sources and directs the pulses of illumination along an illumination path to a plurality of field mirror facets. The field mirror facets receive at least a portion of illumination from the illumination path and direct at least a portion of the illumination to a plurality of pupil mirror facets. The pupil mirror facets receive at least a portion of illumination reflected from the field mirror facets and direct the portion of illumination along a delivery path to a reticle for imaging and/or defect inspection.

Illumination system with time multiplexed sources for reticle inspection

Methods and systems for inspection of a specimen using different parameters are provided. One computer-implemented method includes determining optimal parameters for inspection based on selected defects. This method also includes setting parameters of an inspection system at the optimal parameters prior to inspection. Another method for inspecting a specimen includes illuminating the specimen with light having a wavelength below about 350 nm and with light having a wavelength above about 350 nm. The method also includes processing signals representative of light collected from the specimen to detect defects or process variations on the specimen. One system configured to inspect a specimen includes a first optical subsystem coupled to a broadband light source and a second optical subsystem coupled to a laser. The system also includes a third optical subsystem configured to couple light from the first and second optical subsystems to an objective, which focuses the light onto the specimen.

Methods and systems for inspection of a specimen using different inspection parameters

Systems configured to generate output corresponding to defects on a specimen and systems configured to generate phase information about defects on a specimen are provided. One system includes an optical subsystem that is configured to create interference between a test beam and a reference beam. The test beam and the reference beam are reflected from the specimen. The system also includes a detector that is configured to generate output representative of the interference between the test and reference beams. The interference increases contrast between the output corresponding to the defects and output corresponding to non-defective portions of the specimen.

Systems configured to generate output corresponding to defects on a specimen

A semiconductor wafer inspection system and method is provided which uses a multiple element arrangement, such as an offset fly lens array. The preferred embodiment uses a laser to transmit light energy toward a beam expander, which expands the light energy to create an illumination field. An offset fly lens array converts light energy from the illumination field into an offset pattern of illumination spots. A lensing arrangement, including a first lens, a transmitter/reflector, an objective, and a Mag tube imparts light energy onto the specimen and passes the light energy toward a pinhole mask. The pinhole mask is mechanically aligned with the offset fly lens array. Light energy passing through each pinhole in the pinhole mask is directed toward a relay lens, which guides light energy onto a sensor. The offset fly lens array corresponds to the pinhole mask. The offset pattern of the offset fly lens array is chosen such that spots produced can be recombined into a continuous image, and the system utilizes a time delay and integration charge coupled device for rapid sensing along with an autofocus system that measures and cancels topological features of the specimen.

Confocal wafer inspection system and method

Systems configured to inspect a specimen are provided. One system includes an illumination subsystem configured to illuminate a two-dimensional field of view on the specimen. The system also includes a collection subsystem configured to collect light scattered from the specimen. In addition, the system includes an array of micro-mirrors configured to reflect a two-dimensional pattern of light diffracted from periodic structures on the specimen out of the optical path of the system without reflecting light across an entire dimension of the array out of the optical path. The system further includes a detection subsystem configured to generate output responsive to light reflected by the array into the optical path. The output can be used to detect defects on the specimen. In one embodiment, the system includes an optical element configured to increase the uniformity of the wavefront of the light reflected by the array into the optical path.

Systems configured to inspect a specimen

The broadband brightfield/darkfield wafer inspection system provided receives broadband brightfield illumination information via a defect detector, which signals for initiation of darkfield illumination. The defect detector forms a two dimensional histogram of the defect data and a dual mode defect decision algorithm and post processor assess defects. Darkfield radiation is provided by two adjustable height laser beams. Vertical angular adjustability is provided by modifying cylindrical lens position to compensate for angular mirror change by translating an adjustable mirror, positioning the illumination spot into the sensor field of view, rotating and subsequently moving the cylindrical lens. A brightfield beamsplitter in the system is removable, and preferably replaced with a blank when performing darkfield illumination. Light level control for the system is provided by a dual polarizer first stage.

High throughput darkfield/brightfield wafer inspection system using advanced optical techniques

Accordingly, the present invention provides methods and apparatus for performing a darkfield inspection on a specimen having periodic structures thereon while substantially reducing or eliminating the long range ringing response, which is typically produced by a traditional Fourier filter mask used to eliminate the diffraction caused by the periodic structures. In one embodiment, an apparatus for inspecting a specimen by detecting optical beams scattered from the specimen. The apparatus includes a beam generator for providing and directing an incident beam towards a specimen and an array subtraction device for substantially subtracting a periodic component from an output beam scattered from the specimen in response to the incident beam. The periodic component corresponds to at least one periodic structure on the specimen, and the subtraction is performed so as to substantially reduce or eliminate a ringing response from the output beam. The subtraction is also performed so as to substantially prevent subtracting any actual defect components from the output beam. The apparatus further includes a detector for receiving the output beam and generating an output image or signal based on the output beam.

Dark field inspection apparatus and methods

Confocal wafer inspection method and apparatus using fly lens arrangement

The broadband brightfield/darkfield wafer inspection system provided receives broadband brightfield illumination information via a defect detector, which signals for initiation of darkfield illumination. The defect detector forms a two dimensional histogram of the defect data and a dual mode defect decision algorithm and post processor assess defects. Darkfield radiation is provided by two adjustable height laser beams. Vertical angular adjustability is provided by modifying cylindrical lens position to compensate for angular mirror change by translating an adjustable mirror, positioning the illumination spot into the sensor field of view, rotating and subsequently moving the cylindrical lens. Light level control for the system is provided by a dual polarizer first stage. Light exiting from the second polarizer passes through a filter which absorbs a portion of the light and comprises the second stage of light control.

High throughput brightfield/darkfield wafer inspection system using advanced optical techniques

A system and method for coherent optical inspection are described. In one embodiment, an illuminating beam illuminates a sample, such as a semiconductor wafer, to generate a reflected beam. A reference beam then interferes with the reflected beam to generate an interference pattern at a detector, which records the interference pattern. The interference pattern may then be compared with a comparison image to determine differences between the interference pattern and the comparison image. According to another aspect, the phase difference between the reference beam and the reflected beam may be adjusted to enhance signal contrast. Another embodiment provides for using differential interference techniques to suppress a regular pattern in the sample.

System and method for coherent optical inspection

A filter to selectively block light from passing through the filter and to selectively permit light to pass through the filter. The filter includes an array with a plurality of individually addressable filter elements. Each filter element is selectively settable to have a variable transmittance to the light of between substantially zero percent and substantially one hundred percent. In this manner, the filter according to the present invention provides areas that pass only a portion of the light, and thus can block the light using patterns other than just an abrupt on/off filtering. By so doing, the filter is able to dramatically reduce, and in some embodiments eliminate, the light ringing that typically accompanies such on/off filters.

Growing community of inventors

Fremont, CA, United States of America

Tao-Yi Fu