Kla Tencor Corporation

Kla-tencor Technologies Corporation

Kla Corporation

Stephen Biellak

Daniel Ivanov Kavaldjiev

Christian Wolters

Mehdi Vaez-Iravani

Guoheng Zhao

Anatoly Romanovsky

David W Shortt

Zhiwei Xu

Ivan Maleev

Bret Whiteside

Juergen Reich

Ximan Jiang

Dirk Woll

George J Kren

Michael D Kirk

Jehn-Huar Chern

Yury Yuditsky

Jijen Vazhaeparambil

Tzi-Cheng Lai

Yung-Ho Alex Chuang

John Fielden

Jaydeep K Sinha

Haiguang Chen

Donald Pettibone

Kurt Lindsay Haller

Aleksey Petrenko

Mous Tatarkhanov

David Lee Brown

Stuart L Friedman

Qing Li

Steve Yifeng Cui

Alexander Belyaev

Prasanna Dighe

Devis Contarato

Guowu Zheng

Andrew Steinbach

Azmi Kadkly

Sam Shamouilian

Louis Vintro

Tyler Trytko

Jehn-Huar Chem

Systems, methods, and apparatuses are disclosed herein for directing, using an optical arrangement including one or more lenses, a main beam and a leading beam toward a specimen such that the main beam is incident on the specimen at a main beam incidence and the leading beam is incident on the specimen at a leading beam incidence. The main beam intensity is greater than a leading beam intensity of the leading beam. A TDI sensor receives electromagnetic radiation from the leading beam incidence, thereby generating a first accumulated charge portion, and receives electromagnetic radiation from the main beam incidence, thereby generating a second accumulated charge portion. A processor maps the first accumulated charge portion to a first FOV, thereby yielding leading beam data, and maps the second accumulated charge portion to a second FOV, thereby yielding main beam data.

Systems and methods for advanced defect ablation protection

First and second images of a semiconductor die or portion thereof are generated. Generating each image includes performing a respective instance of time-domain integration (TDI) along a plurality of pixel columns in an imaging sensor, while illuminating the imaging sensor with light scattered from the semiconductor die or portion thereof. The plurality of pixel columns comprises pairs of pixel columns in which the pixel columns are separated by respective channel stops. While performing a first instance of TDI to generate the first image, a first bias is applied to electrically conductive contacts of the channel stops. While performing a second instance of TDI to generate the second image, a second bias is applied to the electrically conductive contacts of the channel stops. Defects in the semiconductor die or portion thereof are identified using the first and second images.

Multi-pass imaging using image sensors with variably biased channel-stop contacts for identifying defects in a semiconductor die

A back-illuminated image sensor includes a first pixel, a second pixel, and a channel stop situated between the first pixel and the second pixel to isolate the first pixel from the second pixel. The channel stop includes a LOCOS structure and a region of doped silicon beneath the LOCOS structure. The back-illuminated image sensor also includes a first electrically conductive contact that extends through the LOCOS structure and forms an ohmic contact with the region of doped silicon. The first electrically conductive contact may be grounded, negatively biased, or positively biased, depending on the application.

Image sensors with grounded or otherwise biased channel-stop contacts

An image sensor is provided that includes a pixel array divided into a plurality of pixel groups. Each pixel group is clocked by a respective plurality of horizontal-register clocks. Clock signals for the image sensor are adjusted. Adjusting the clock signals includes phase-shifting each plurality of horizontal-register clocks by a respective phase delay of a plurality of phase delays. The phase delays are evenly spaced and are spaced symmetrically about zero. With the clock signals adjusted, a target is imaged using the image sensor.

Spread-spectrum clock-signal adjustment for image sensors

An inspection system with radiation-induced false count mitigation includes an illumination source configured to illuminate a sample and a liquid-cooling coincidence detector, which includes an illumination detector to detect illumination from the sample, a liquid-cooling device for regulating a temperature of the illumination detector via a liquid, and photodetectors to detect light generated in the liquid in response to particle radiation. The liquid-cooling coincidence detector may also include controllers to identify a set of illumination detection events based on an illumination signal received from the illumination detector, identify a set of radiation detection events based on radiation signals received from the photodetectors, compare the set of radiation detection events to the set of illumination detection events to identify a set of coincidence events, and exclude the set of coincidence events from the set of illumination detection events to generate a set of identified features on the sample.

Radiation-induced false count mitigation and detector cooling

Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to direct pulses of light to an area on a wafer; a scanning subsystem configured to scan the pulses of light across the wafer; a collection subsystem configured to image pulses of light scattered from the area on the wafer to a sensor, wherein the sensor is configured to integrate a number of the pulses of scattered light that is fewer than a number of the pulses of scattered light that can be imaged on the entire area of the sensor, and wherein the sensor is configured to generate output responsive to the integrated pulses of scattered light; and a computer subsystem configured to detect defects on the wafer using the output generated by the sensor.

Wafer inspection

An inspection system and methods in which analog image data values (charges) captured by an image sensor are binned (combined) before or while being transmitted as output signals on the image sensor's output sensing nodes (floating diffusions), and in which an ADC is controlled to sequentially generate multiple corresponding digital image data values between each reset of the output sensing nodes. According to an output binning method, the image sensor is driven to sequentially transfer multiple charges onto the output sensing nodes between each reset, and the ADC is controlled to convert the incrementally increasing output signal after each charge is transferred onto the output sensing node. According to a multi-sampling method, multiple charges are vertically or horizontally binned (summed/combined) before being transferred onto the output sensing node, and the ADC samples each corresponding output signal multiple times. The output binning and multi-sampling methods may be combined.

Dark-field inspection using a low-noise sensor

An inspection system with radiation-induced false count mitigation includes a radiation count controller coupled to one or more radiation sensors positioned proximate to an illumination sensor oriented to detect illumination from a sample. The radiation count controller may identify a set of radiation detection events based on radiation signals received from the radiation sensors during operation of the illumination sensor. The inspection system may further include an inspection controller to identify a set of illumination detection events based on an illumination signal, identify one or more features on the sample based on the set of illumination detection events, receive the set of radiation detection events from the radiation count controller, compare the set of radiation detection events to the set of illumination detection events to identify a set of coincidence events, and refine the one or more identified features on the sample based on the set of coincidence events.

System and method for reducing radiation-induced false counts in an inspection system

A wafer scanning system includes imaging collection optics to reduce the effective spot size. Smaller spot size decreases the number of photons scattered by the surface proportionally to the area of the spot. Air scatter is also reduced. TDI is used to produce a wafer image based on a plurality of image signals integrated over the direction of linear motion of the wafer. An illumination system floods the wafer with light, and the task of creating the spot is allocated to the imaging collection optics.

TDI sensor in a darkfield system

An inspection system with radiation-induced false count mitigation includes an illumination source configured to illuminate a sample, a detector assembly comprising an illumination sensor configured to detect illumination from the sample, and one or more radiation sensors configured to detect particle radiation, and control circuitry communicatively coupled to the detector. The control circuitry is configured to perform the steps of determining a set of radiation detection events based on one or more radiation signals received from the radiation sensors, determining a set of imaging events based on the illumination signal received from the illumination sensor, comparing the set of radiation detection events to the set of imaging events to generate a set of coincidence events, wherein the set of coincidence events comprises simultaneous imaging and radiation detection events, and excluding the set of coincidence events from the set of imaging events to generate a set of identified defect sites.

A method and system for providing illumination is disclosed. The method may include providing a laser having a predetermined wavelength; performing at least one of: beam splitting or beam scanning prior to a frequency conversion; converting a frequency of each output beam of the at least one of: beam splitting or beam scanning; and providing the frequency converted output beam for illumination.

Laser with integrated multi line or scanning beam capability

The disclosure is directed to image intensifier tube designs for field curvature aberration correction and ion damage reduction. In some embodiments, electrodes defining an acceleration path from a photocathode to a scintillating screen are configured to provide higher acceleration for off-axis electrons along at least a portion of the acceleration path. Off-axis electrons and on-axis electrons are accordingly focused on the scintillating screen with substantial uniformity to prevent or reduce field curvature aberration. In some embodiments, the electrodes are configured to generate a repulsive electric field near the scintillating screen to prevent secondary electrons emitted or deflected by the scintillating screen from flowing towards the photocathode and forming damaging ions.

Image intensifier tube design for aberration correction and ion damage reduction

Methods and systems for detection of selected defects in relatively noisy inspection data are provided. One method includes applying a spatial filter algorithm to inspection data acquired across an area on a substrate to determine a first portion of the inspection data that has a higher probability of being a selected type of defect than a second portion of the inspection data. The selected type of defect includes a non-point defect. The inspection data is generated by combining two or more raw inspection data corresponding to substantially the same locations on the substrate. The method also includes generating a two-dimensional map illustrating the first portion of the inspection data. The method further includes searching the two-dimensional map for an event that has spatial characteristics that approximately match spatial characteristics of the selected type of defect and determining if the event corresponds to a defect having the selected type.

Detection of selected defects in relatively noisy inspection data

An electron-bombarded detector for detecting low light signals includes a vacuum tube structure defining a cylindrical vacuum tube chamber, a photocathode disposed at a first end of the vacuum tube chamber, a sensor disposed at a second end of the vacuum tube chamber, ring electrodes disposed in the vacuum tube chamber for generating an electric field that accelerates emitted photoelectrons toward the sensor, and a magnetic field generator configured to generate a symmetric magnetic field that applies a focusing lens effect on the photoelectrons. The ring electrodes and magnetic field generator are operating using one of a reduced distance focusing approach and an acceleration/deceleration approach such that the photoelectrons have a landing energy below 2 keV. The use of reflective mode photocathodes is enabled using either multi-pole deflector coils, or ring electrodes formed by segmented circular electrode structures. Large angle deflections are achieved using magnetic or electrostatic deflectors.

High resolution high quantum efficiency electron bombarded CCD or CMOS imaging sensor

Growing community of inventors

Sunnyvale, CA, United States of America

Stephen Biellak